#### Sample records for hydrogen storage challenges

1. Hydrogen storage: the remaining scientific and technological challenges.

PubMed

Felderhoff, Michael; Weidenthaler, Claudia; von Helmolt, Rittmar; Eberle, Ulrich

2007-06-01

To ensure future worldwide mobility, hydrogen storage in combination with fuel cells for on-board automotive applications is one of the most challenging issues. Potential solid-state solutions have to fulfil operating requirements defined by the fuel cell propulsion system. Important requirements are also defined by customer demands such as cost, overall fuel capacity, refuelling time and efficiency. It seems that currently none of the different storage solid state materials can reach the required storage densities for a hydrogen-powered vehicle. New strategies for storage systems are necessary to fulfil the requirements for a broad introduction of automotive fuel cell powertrains to the market. The combination of different storage systems may provide a possible solution to store sufficiently high amounts of hydrogen. PMID:17627309

2. Outlook and challenges for hydrogen storage in nanoporous materials

Broom, D. P.; Webb, C. J.; Hurst, K. E.; Parilla, P. A.; Gennett, T.; Brown, C. M.; Zacharia, R.; Tylianakis, E.; Klontzas, E.; Froudakis, G. E.; Steriotis, Th. A.; Trikalitis, P. N.; Anton, D. L.; Hardy, B.; Tamburello, D.; Corgnale, C.; van Hassel, B. A.; Cossement, D.; Chahine, R.; Hirscher, M.

2016-03-01

Considerable progress has been made recently in the use of nanoporous materials for hydrogen storage. In this article, the current status of the field and future challenges are discussed, ranging from important open fundamental questions, such as the density and volume of the adsorbed phase and its relationship to overall storage capacity, to the development of new functional materials and complete storage system design. With regard to fundamentals, the use of neutron scattering to study adsorbed H2, suitable adsorption isotherm equations, and the accurate computational modelling and simulation of H2 adsorption are discussed. The new materials covered include flexible metal-organic frameworks, core-shell materials, and porous organic cage compounds. The article concludes with a discussion of the experimental investigation of real adsorptive hydrogen storage tanks, the improvement in the thermal conductivity of storage beds, and new storage system concepts and designs.

3. Outlook and Challenges for Hydrogen Storage in Nanoporous Materials

DOE PAGES

Broom, D. P.; Webb, C. J.; Hurst, Katherine E.; Parilla, Philip A.; Gennett, Thomas; Brown, C. M.; Zacharia, R.; Tylianakis, E.; Klontzas, E.; Froudakis, G. E.; et al

2016-02-16

Considerable progress has been made recently in the use of nanoporous materials for hydrogen storage. In our article, the current status of the field and future challenges are discussed, ranging from important open fundamental questions, such as the density and volume of the adsorbed phase and its relationship to overall storage capacity, to the development of new functional materials and complete storage system design. With regard to fundamentals, the use of neutron scattering to study adsorbed H2, suitable adsorption isotherm equations, and the accurate computational modelling and simulation of H2 adsorption are discussed. We cover new materials and they includemore » flexible metal–organic frameworks, core–shell materials, and porous organic cage compounds. The article concludes with a discussion of the experimental investigation of real adsorptive hydrogen storage tanks, the improvement in the thermal conductivity of storage beds, and new storage system concepts and designs.« less

4. Key challenges and recent progress in batteries, fuel cells, and hydrogen storage for clean energy systems

Chalk, Steven G.; Miller, James F.

Reducing or eliminating the dependency on petroleum of transportation systems is a major element of US energy research activities. Batteries are a key enabling technology for the development of clean, fuel-efficient vehicles and are key to making today's hybrid electric vehicles a success. Fuel cells are the key enabling technology for a future hydrogen economy and have the potential to revolutionize the way we power our nations, offering cleaner, more efficient alternatives to today's technology. Additionally fuel cells are significantly more energy efficient than combustion-based power generation technologies. Fuel cells are projected to have energy efficiency twice that of internal combustion engines. However before fuel cells can realize their potential, significant challenges remain. The two most important are cost and durability for both automotive and stationary applications. Recent electrocatalyst developments have shown that Pt alloy catalysts have increased activity and greater durability than Pt catalysts. The durability of conventional fluorocarbon membranes is improving, and hydrocarbon-based membranes have also shown promise of equaling the performance of fluorocarbon membranes at lower cost. Recent announcements have also provided indications that fuel cells can start from freezing conditions without significant deterioration. Hydrogen storage systems for vehicles are inadequate to meet customer driving range expectations (>300 miles or 500 km) without intrusion into vehicle cargo or passenger space. The United States Department of Energy has established three centers of Excellence for hydrogen storage materials development. The centers are focused on complex metal hydrides that can be regenerated onboard a vehicle, chemical hydrides that require off-board reprocessing, and carbon-based storage materials. Recent developments have shown progress toward the 2010 DOE targets. In addition DOE has established an independent storage material testing center

5. Ultrafine hydrogen storage powders

DOEpatents

Anderson, Iver E.; Ellis, Timothy W.; Pecharsky, Vitalij K.; Ting, Jason; Terpstra, Robert; Bowman, Robert C.; Witham, Charles K.; Fultz, Brent T.; Bugga, Ratnakumar V.

2000-06-13

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

6. Hydrogen storage compositions

SciTech Connect

Li, Wen; Vajo, John J.; Cumberland, Robert W.; Liu, Ping

2011-04-19

Compositions for hydrogen storage and methods of making such compositions employ an alloy that exhibits reversible formation/deformation of BH.sub.4.sup.- anions. The composition includes a ternary alloy including magnesium, boron and a metal and a metal hydride. The ternary alloy and the metal hydride are present in an amount sufficient to render the composition capable of hydrogen storage. The molar ratio of the metal to magnesium and boron in the alloy is such that the alloy exhibits reversible formation/deformation of BH.sub.4.sup.- anions. The hydrogen storage composition is prepared by combining magnesium, boron and a metal to prepare a ternary alloy and combining the ternary alloy with a metal hydride to form the hydrogen storage composition.

7. Hydrogen storage methods.

PubMed

Züttel, Andreas

2004-04-01

Hydrogen exhibits the highest heating value per mass of all chemical fuels. Furthermore, hydrogen is regenerative and environmentally friendly. There are two reasons why hydrogen is not the major fuel of today's energy consumption. First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water and hydrocarbons. This implies that we have to pay for the energy, which results in a difficult economic dilemma because ever since the industrial revolution we have become used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is its low critical temperature of 33 K (i.e. hydrogen is a gas at ambient temperature). For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage material is crucial. Hydrogen can be stored using six different methods and phenomena: (1) high-pressure gas cylinders (up to 800 bar), (2) liquid hydrogen in cryogenic tanks (at 21 K), (3) adsorbed hydrogen on materials with a large specific surface area (at T<100 K), (4) absorbed on interstitial sites in a host metal (at ambient pressure and temperature), (5) chemically bonded in covalent and ionic compounds (at ambient pressure), or (6) through oxidation of reactive metals, e.g. Li, Na, Mg, Al, Zn with water. The most common storage systems are high-pressure gas cylinders with a maximum pressure of 20 MPa (200 bar). New lightweight composite cylinders have been developed which are able to withstand pressures up to 80 MPa (800 bar) and therefore the hydrogen gas can reach a volumetric density of 36 kg.m(-3), approximately half as much as in its liquid state. Liquid hydrogen is stored in cryogenic tanks at 21.2 K and ambient pressure. Due to the low critical temperature of hydrogen (33 K), liquid hydrogen can only be stored in open systems. The volumetric density of liquid hydrogen

8. Hydrogen storage methods

Züttel, Andreas

Hydrogen exhibits the highest heating value per mass of all chemical fuels. Furthermore, hydrogen is regenerative and environmentally friendly. There are two reasons why hydrogen is not the major fuel of today's energy consumption. First of all, hydrogen is just an energy carrier. And, although it is the most abundant element in the universe, it has to be produced, since on earth it only occurs in the form of water and hydrocarbons. This implies that we have to pay for the energy, which results in a difficult economic dilemma because ever since the industrial revolution we have become used to consuming energy for free. The second difficulty with hydrogen as an energy carrier is its low critical temperature of 33 K (i.e. hydrogen is a gas at ambient temperature). For mobile and in many cases also for stationary applications the volumetric and gravimetric density of hydrogen in a storage material is crucial. Hydrogen can be stored using six different methods and phenomena: (1) high-pressure gas cylinders (up to 800 bar), (2) liquid hydrogen in cryogenic tanks (at 21 K), (3) adsorbed hydrogen on materials with a large specific surface area (at T<100 K), (4) absorbed on interstitial sites in a host metal (at ambient pressure and temperature), (5) chemically bonded in covalent and ionic compounds (at ambient pressure), or (6) through oxidation of reactive metals, e.g. Li, Na, Mg, Al, Zn with water. The most common storage systems are high-pressure gas cylinders with a maximum pressure of 20 MPa (200 bar). New lightweight composite cylinders have been developed which are able to withstand pressures up to 80 MPa (800 bar) and therefore the hydrogen gas can reach a volumetric density of 36 kg.m-3, approximately half as much as in its liquid state. Liquid hydrogen is stored in cryogenic tanks at 21.2 K and ambient pressure. Due to the low critical temperature of hydrogen (33 K), liquid hydrogen can only be stored in open systems. The volumetric density of liquid hydrogen is

9. Hydrogen Storage Technical Team Roadmap

SciTech Connect

2013-06-01

The mission of the Hydrogen Storage Technical Team is to accelerate research and innovation that will lead to commercially viable hydrogen-storage technologies that meet the U.S. DRIVE Partnership goals.

10. Nanostructured materials for hydrogen storage

DOEpatents

Williamson, Andrew J.; Reboredo, Fernando A.

2007-12-04

A system for hydrogen storage comprising a porous nano-structured material with hydrogen absorbed on the surfaces of the porous nano-structured material. The system of hydrogen storage comprises absorbing hydrogen on the surfaces of a porous nano-structured semiconductor material.

11. Electrochemical hydrogen Storage Systems

SciTech Connect

Dr. Digby Macdonald

2010-08-09

As the global need for energy increases, scientists and engineers have found a possible solution by using hydrogen to power our world. Although hydrogen can be combusted as a fuel, it is considered an energy carrier for use in fuel cells wherein it is consumed (oxidized) without the production of greenhouse gases and produces electrical energy with high efficiency. Chemical storage of hydrogen involves release of hydrogen in a controlled manner from materials in which the hydrogen is covalently bound. Sodium borohydride and aminoborane are two materials given consideration as chemical hydrogen storage materials by the US Department of Energy. A very significant barrier to adoption of these materials as hydrogen carriers is their regeneration from 'spent fuel,' i.e., the material remaining after discharge of hydrogen. The U.S. Department of Energy (DOE) formed a Center of Excellence for Chemical Hydrogen Storage, and this work stems from that project. The DOE has identified boron hydrides as being the main compounds of interest as hydrogen storage materials. The various boron hydrides are then oxidized to release their hydrogen, thereby forming a 'spent fuel' in the form of a lower boron hydride or even a boron oxide. The ultimate goal of this project is to take the oxidized boron hydrides as the spent fuel and hydrogenate them back to their original form so they can be used again as a fuel. Thus this research is essentially a boron hydride recycling project. In this report, research directed at regeneration of sodium borohydride and aminoborane is described. For sodium borohydride, electrochemical reduction of boric acid and sodium metaborate (representing spent fuel) in alkaline, aqueous solution has been investigated. Similarly to literature reports (primarily patents), a variety of cathode materials were tried in these experiments. Additionally, approaches directed at overcoming electrostatic repulsion of borate anion from the cathode, not described in the

12. Enhancing hydrogen spillover and storage

DOEpatents

Yang, Ralph T.; Li, Yingwel; Lachawiec, Jr., Anthony J.

2011-05-31

Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonification as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

13. Enhancing hydrogen spillover and storage

DOEpatents

Yang, Ralph T; Li, Yingwei; Lachawiec, Jr., Anthony J

2013-02-12

Methods for enhancing hydrogen spillover and storage are disclosed. One embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the hydrogen receptor to ultrasonication as doping occurs. Another embodiment of the method includes doping a hydrogen receptor with metal particles, and exposing the doped hydrogen receptor to a plasma treatment.

14. Gas storage materials, including hydrogen storage materials

SciTech Connect

Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

2013-02-19

A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

15. Gas storage materials, including hydrogen storage materials

SciTech Connect

Mohtadi, Rana F; Wicks, George G; Heung, Leung K; Nakamura, Kenji

2014-11-25

A material for the storage and release of gases comprises a plurality of hollow elements, each hollow element comprising a porous wall enclosing an interior cavity, the interior cavity including structures of a solid-state storage material. In particular examples, the storage material is a hydrogen storage material, such as a solid state hydride. An improved method for forming such materials includes the solution diffusion of a storage material solution through a porous wall of a hollow element into an interior cavity.

16. Reversible hydrogen storage materials

DOEpatents

Ritter, James A.; Wang, Tao; Ebner, Armin D.; Holland, Charles E.

2012-04-10

In accordance with the present disclosure, a process for synthesis of a complex hydride material for hydrogen storage is provided. The process includes mixing a borohydride with at least one additive agent and at least one catalyst and heating the mixture at a temperature of less than about 600.degree. C. and a pressure of H.sub.2 gas to form a complex hydride material. The complex hydride material comprises MAl.sub.xB.sub.yH.sub.z, wherein M is an alkali metal or group IIA metal, Al is the element aluminum, x is any number from 0 to 1, B is the element boron, y is a number from 0 to 13, and z is a number from 4 to 57 with the additive agent and catalyst still being present. The complex hydride material is capable of cyclic dehydrogenation and rehydrogenation and has a hydrogen capacity of at least about 4 weight percent.

17. Storage, transmission and distribution of hydrogen

NASA Technical Reports Server (NTRS)

Kelley, J. H.; Hagler, R., Jr.

1979-01-01

Current practices and future requirements for the storage, transmission and distribution of hydrogen are reviewed in order to identify inadequacies to be corrected before hydrogen can achieve its full potential as a substitute for fossil fuels. Consideration is given to the storage of hydrogen in underground solution-mined salt caverns, portable high-pressure containers and dewars, pressure vessels and aquifers and as metal hydrides, hydrogen transmission in evacuated double-walled insulated containers and by pipeline, and distribution by truck and internal distribution networks. Areas for the improvement of these techniques are indicated, and these technological deficiencies, including materials development, low-cost storage and transmission methods, low-cost, long-life metal hydrides and novel methods for hydrogen storage, are presented as challenges for research and development.

18. Designing Microporus Carbons for Hydrogen Storage Systems

SciTech Connect

Alan C. Cooper

2012-05-02

An efficient, cost-effective hydrogen storage system is a key enabling technology for the widespread introduction of hydrogen fuel cells to the domestic marketplace. Air Products, an industry leader in hydrogen energy products and systems, recognized this need and responded to the DOE 'Grand Challenge' solicitation (DOE Solicitation DE-PS36-03GO93013) under Category 1 as an industry partner and steering committee member with the National Renewable Energy Laboratory (NREL) in their proposal for a center-of-excellence on Carbon-Based Hydrogen Storage Materials. This center was later renamed the Hydrogen Sorption Center of Excellence (HSCoE). Our proposal, entitled 'Designing Microporous Carbons for Hydrogen Storage Systems,' envisioned a highly synergistic 5-year program with NREL and other national laboratory and university partners.

19. Hydrogen storage and generation system

DOEpatents

Dentinger, Paul M.; Crowell, Jeffrey A. W.

2010-08-24

A system for storing and generating hydrogen generally and, in particular, a system for storing and generating hydrogen for use in an H.sub.2/O.sub.2 fuel cell. The hydrogen storage system uses the beta particles from a beta particle emitting material to degrade an organic polymer material to release substantially pure hydrogen. In a preferred embodiment of the invention, beta particles from .sup.63Ni are used to release hydrogen from linear polyethylene.

20. Measurements of Hydrogen Storage

Meisner, Gregory P.

2004-03-01

The many sensational claims of vast quantities of hydrogen (H) stored in carbon materials reported since 1996 have resulted in the H storage and carbon scientific literature now being cluttered with misinformation and some genuinely bad science. H storage experiments are not trivial, and they are prone to error and misinterpretation. For example, volumetric experiments use equilibrium gas pressures (P) and temperatures (T) measured in calibrated volumes to determine the number of moles of gas, and changes in P without changes in T (or leakage) are then interpreted as sorption. A typical mistake is measuring P vs. time after pressurizing a sample chamber and interpreting a drop in P as sorption. This is difficult to interpret as real absorption because all confounding effects (leaks, T drifts, thermal inhomogeneities, etc.) are nearly impossible to eliminate. Moreover, the basic thermodynamic properties of gas flow systems tell us that high-P gases filling evacuated chambers experience non-negligible rises in T. Another example of misinterpretation arises in gravimetric experiments that use weight (W) measurements corrected for large T-dependent buoyancy effects to determine gas sorption. Here a typical mistake is interpreting the actual sorption of heavy residual impurity gases as H sorption. These and other techniques for measuring H sorption must be performed and interpreted with great care due to difficulties associated with small sample sizes, high gas pressures, very reactive materials, contamination, low signal-to-noise, poor experimental design, and, in some cases, bad science. Good science respects the difference between measurement precision (the number of significant digits of P or W measurements) and experimental accuracy (the degree of certainty that P or W changes really represent H sorption). At General Motors, we endeavor to understand, conduct, and promote reliable H storage measurements on new materials and routinely use both volumetric

1. Polyhydride complexes for hydrogen storage

SciTech Connect

Jensen, C.M.

1995-09-01

Polyhydride metal complexes are being developed for application in hydrogen storage. Efforts have focused on developing complexes with improved available hydrogen weight percentages. We have explored the possibility that complexes containing aromatic hydrocarbon ligands could store hydrogen at both the metal center and in the ligands. We have synthesized novel indenyl hydride complexes and explored their reactivity with hydrogen. The reversible hydrogenation of [IrH{sub 3}(PPh{sub 3})({eta}{sup 5}-C{sub 10}H{sub 7})]{sup +} has been achieved. While attempting to prepare {eta}{sup 6}-tetrahydronaphthalene complexes, we discovered that certain polyhydride complexes catalyze both the hydrogenation and dehydrogenation of tetrahydronaphthalene.

2. Carbon material for hydrogen storage

DOEpatents

Bourlinos, Athanasios; Steriotis, Theodore; Stubos, Athanasios; Miller, Michael A

2016-09-13

The present invention relates to carbon based materials that are employed for hydrogen storage applications. The material may be described as the pyrolysis product of a molecular precursor such as a cyclic quinone compound. The pyrolysis product may then be combined with selected transition metal atoms which may be in nanoparticulate form, where the metals may be dispersed on the material surface. Such product may then provide for the reversible storage of hydrogen. The metallic nanoparticles may also be combined with a second metal as an alloy to further improve hydrogen storage performance.

3. Catalyzed borohydrides for hydrogen storage

DOEpatents

Au, Ming

2012-02-28

A hydrogen storage material and process is provided in which alkali borohydride materials are created which contain effective amounts of catalyst(s) which include transition metal oxides, halides, and chlorides of titanium, zirconium, tin, and combinations of the various catalysts. When the catalysts are added to an alkali borodydride such as a lithium borohydride, the initial hydrogen release point of the resulting mixture is substantially lowered. Additionally, the hydrogen storage material may be rehydrided with weight percent values of hydrogen at least about 9 percent.

4. Complex Hydrides for Hydrogen Storage

SciTech Connect

Slattery, Darlene; Hampton, Michael

2003-03-10

This report describes research into the use of complex hydrides for hydrogen storage. The synthesis of a number of alanates, (AIH4) compounds, was investigated. Both wet chemical and mechano-chemical methods were studied.

5. Complex hydrides for hydrogen storage

DOEpatents

Zidan, Ragaiy

2006-08-22

A hydrogen storage material and process of forming the material is provided in which complex hydrides are combined under conditions of elevated temperatures and/or elevated temperature and pressure with a titanium metal such as titanium butoxide. The resulting fused product exhibits hydrogen desorption kinetics having a first hydrogen release point which occurs at normal atmospheres and at a temperature between 50.degree. C. and 90.degree. C.

6. ALUMINUM HYDRIDE: A REVERSIBLE STORAGE MATERIAL FOR HYDROGEN STORAGE

SciTech Connect

Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J

2009-01-09

One of the challenges of implementing the hydrogen economy is finding a suitable solid H{sub 2} storage material. Aluminium (alane, AlH{sub 3}) hydride has been examined as a potential hydrogen storage material because of its high weight capacity, low discharge temperature, and volumetric density. Recycling the dehydride material has however precluded AlH{sub 3} from being implemented due to the large pressures required (>10{sup 5} bar H{sub 2} at 25 C) and the thermodynamic expense of chemical synthesis. A reversible cycle to form alane electrochemically using NaAlH{sub 4} in THF been successfully demonstrated. Alane is isolated as the triethylamine (TEA) adduct and converted to unsolvated alane by heating under vacuum. To complete the cycle, the starting alanate can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride (NaH) This novel reversible cycle opens the door for alane to fuel the hydrogen economy.

7. Metastable Metal Hydrides for Hydrogen Storage

DOE PAGES

Graetz, Jason

2012-01-01

The possibility of using hydrogen as a reliable energy carrier for both stationary and mobile applications has gained renewed interest in recent years due to improvements in high temperature fuel cells and a reduction in hydrogen production costs. However, a number of challenges remain and new media are needed that are capable of safely storing hydrogen with high gravimetric and volumetric densities. Metal hydrides and complex metal hydrides offer some hope of overcoming these challenges; however, many of the high capacity “reversible” hydrides exhibit a large endothermic decomposition enthalpy making it difficult to release the hydrogen at low temperatures. Onmore » the other hand, the metastable hydrides are characterized by a low reaction enthalpy and a decomposition reaction that is thermodynamically favorable under ambient conditions. The rapid, low temperature hydrogen evolution rates that can be achieved with these materials offer much promise for mobile PEM fuel cell applications. However, a critical challenge exists to develop new methods to regenerate these hydrides directly from the reactants and hydrogen gas. This spotlight paper presents an overview of some of the metastable metal hydrides for hydrogen storage and a few new approaches being investigated to address the key challenges associated with these materials.« less

8. High efficiency stationary hydrogen storage

SciTech Connect

Hynek, S.; Fuller, W.; Truslow, S.

1995-09-01

Stationary storage of hydrogen permits one to make hydrogen now and use it later. With stationary hydrogen storage, one can use excess electrical generation capacity to power an electrolyzer, and store the resultant hydrogen for later use or transshipment. One can also use stationary hydrogen as a buffer at fueling stations to accommodate non-steady fueling demand, thus permitting the hydrogen supply system (e.g., methane reformer or electrolyzer) to be sized to meet the average, rather than the peak, demand. We at ADL designed, built, and tested a stationary hydrogen storage device that thermally couples a high-temperature metal hydride to a phase change material (PCM). The PCM captures and stores the heat of the hydriding reaction as its own heat of fusion (that is, it melts), and subsequently returns that heat of fusion (by freezing) to facilitate the dehydriding reaction. A key component of this stationary hydrogen storage device is the metal hydride itself. We used nickel-coated magnesium powder (NCMP) - magnesium particles coated with a thin layer of nickel by means of chemical vapor deposition (CVD). Magnesium hydride can store a higher weight fraction of hydrogen than any other practical metal hydride, and it is less expensive than any other metal hydride. We designed and constructed an experimental NCM/PCM reactor out of 310 stainless steel in the form of a shell-and-tube heat exchanger, with the tube side packed with NCMP and the shell side filled with a eutectic mixture of NaCL, KCl, and MgCl{sub 2}. Our experimental results indicate that with proper attention to limiting thermal losses, our overall efficiency will exceed 90% (DOE goal: >75%) and our overall system cost will be only 33% (DOE goal: <50%) of the value of the delivered hydrogen. It appears that NCMP can be used to purify hydrogen streams and store hydrogen at the same time. These prospects make the NCMP/PCM reactor an attractive component in a reformer-based hydrogen fueling station.

9. Carbon Aerogels for Hydrogen Storage

SciTech Connect

Baumann, T F; Worsley, M; Satcher, J H

2008-08-11

This effort is focused on the design of new nanostructured carbon-based materials that meet the DOE 2010 targets for on-board vehicle hydrogen storage. Carbon aerogels (CAs) are a unique class of porous materials that possess a number of desirable structural features for the storage of hydrogen, including high surface areas (over 3000 m{sup 2}/g), continuous and tunable porosities, and variable densities. In addition, the flexibility associated with CA synthesis allows for the incorporation of modifiers or catalysts into the carbon matrix in order to alter hydrogen sorption enthalpies in these materials. Since the properties of the doped CAs can be systematically modified (i.e. amount/type of dopant, surface area, porosity), novel materials can be fabricated that exhibit enhanced hydrogen storage properties. We are using this approach to design new H{sub 2} sorbent materials that can storage appreciable amounts of hydrogen at room temperature through a process known as hydrogen spillover. The spillover process involves the dissociative chemisorption of molecular hydrogen on a supported metal catalyst surface (e.g. platinum or nickel), followed by the diffusion of atomic hydrogen onto the surface of the support material. Due to the enhanced interaction between atomic hydrogen and the carbon support, hydrogen can be stored in the support material at more reasonable operating temperatures. While the spillover process has been shown to increase the reversible hydrogen storage capacities at room temperature in metal-loaded carbon nanostructures, a number of issues still exist with this approach, including slow kinetics of H{sub 2} uptake and capacities ({approx} 1.2 wt% on carbon) below the DOE targets. The ability to tailor different structural aspects of the spillover system (i.e. the size/shape of the catalyst particle, the catalyst-support interface and the support morphology) should provide valuable mechanistic information regarding the critical aspects of the

10. Hydrogen storage development

SciTech Connect

Thomas, G.J.; Guthrie, S.E.

1998-08-01

A summary of the hydride development efforts for the current program year (FY98) are presented here. The Mg-Al-Zn alloy system was studied at low Zn levels (2--4 wt%) and midrange Al contents (40--60 wt%). Higher plateau pressures were found with Al and Zn alloying in Mg and, furthermore, it was found that the hydrogen desorption kinetics were significantly improved with small additions of Zn. Results are also shown here for a detailed study of the low temperature properties of Mg{sub 2}NiH{sub 4}, and a comparison made between conventional melt cast alloy and the vapor process material.

11. Hydrogen storage via polyhydride complexes

SciTech Connect

Jensen, C.M.

1996-10-01

Polyhydride metal complexes are being developed for application to hydrogen storage. Complexes have been found which catalyze the reversible hydrogenation of unsaturated hydrocarbons. This catalytic reaction could be the basis for a low temperature, hydrogen storage system with a available hydrogen density greater than 7 weight percent. The P-C-P pincer complexes, RhH{sub 2}(C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}) and IrH{sub 2}(C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}) have unprecedented, long term stability at elevated temperatures. The novel iridium complex catalyzes the transfer dehydrogenation of cycloctane to cyclooctene at the rate of 716 turnovers/h which is 2 orders of magnitude greater than that found for previously reported catalytic systems which do not require the sacrificial hydrogenation of a large excess of hydrogen acceptor.

12. High capacity hydrogen storage nanocomposite materials

DOEpatents

Zidan, Ragaiy; Wellons, Matthew S

2015-02-03

A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

13. Hydrogen storage in platinum decorated hydrogen exfoliated graphene sheets by spillover mechanism.

PubMed

P, Divya; Ramaprabhu, S

2014-12-28

Development of lightweight materials with high hydrogen storage capacities is a great challenge for the hydrogen economy. Here, we report high pressure hydrogen adsorption-desorption studies of platinum-decorated hydrogen-exfoliated graphene sheets (Pt-HEG). Pt-HEG shows a maximum hydrogen uptake capacity of 1.4 wt% at 25 °C and 3 MPa. Analysis of the isosteric heat of adsorption provides evidence of spillover mechanism.

14. Vehicular hydrogen storage using lightweight tanks

SciTech Connect

Mitlitsky, F; Weisberg, A H; Myers, B

2000-07-22

Lightweight hydrogen storage for vehicles is enabled by adopting and adapting aerospace tankage technology. The weight, volume, and cost are already acceptable and improving. Prototype tankage was demonstrated with 11.3% hydrogen by weight, 1.74 million inch (44.3 km) burst performance factor (P{sub b}V/W), and 3.77 kWh/kg specific energy for the tank and hydrogen (LHV). DOE cannot afford full scale aerospace development costs. For example, it costs many tens of M to develop a rocket motor casing with a safety factor (SF) of 1.25. Large teams of experts are required to design, develop, and test new processes. Car companies are buying existing technology with only modest investments in research and development (R&D). The Lawrence Livermore National Laboratory (LLNL) team is maximizing the leverage from DOE funding by joining with industry to solve technical risks at the component level. LLNL is developing fabrication processes with IMPCO Technologies, Thiokol Propulsion, and Aero Tec Laboratories (ATL). LLNL is creating commercial products that are close to adoption under DOE solicitation. LLNL is breaking ground to achieve greater than 10% hydrogen by weight tankage with safety that exceeds the requirements of NGV2 standards modified for hydrogen. Risk reduction is proceeding along three axes: (1) Commercializable products will be available next year with {approx}90% confidence; (2) R&D progress is pushing the envelope in lightweight tankage for vehicles; and (3) Integration challenges are being met with partners in industry and DOE demo programs. This project is a key part of LLNL's effort to develop high cycle life energy storage systems with >600 Wh/kg specific energy for various applications, including: high altitude long endurance solar rechargeable aircraft, zero emission vehicles, hybrid energy storage/propulsion systems for spacecraft, energy storage for premium power, remote power sources, and peak shaving. 15. Composition and method for hydrogen storage NASA Technical Reports Server (NTRS) Mao, Wendy L. (Inventor); Mao, Ho-Kwang (Inventor) 2004-01-01 A method for hydrogen storage includes providing water and hydrogen gas to a containment volume, reducing the temperature of the water and hydrogen gas to form a hydrogen clathrate at a first cryogenic temperature and a first pressure and maintaining the hydrogen clathrate at second cryogenic temperature within a temperature range of up to 250 K to effect hydrogen storage. The low-pressure hydrogen hydrate includes H.sub.2 O molecules, H.sub.2 molecules and a unit cell including polyhedron cages of hydrogen-bonded frameworks of the H.sub.2 O molecules built around the H.sub.2 molecules. 16. Hydrogen-based electrochemical energy storage DOEpatents Simpson, Lin Jay 2013-08-06 An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure. 17. Hydride development for hydrogen storage SciTech Connect Thomas, G.J.; Guthrie, S.E.; Bauer, W.; Yang, N.Y.C.; Sandrock, G. 1996-10-01 The purpose of this project is to develop and demonstrate improved hydride materials for hydrogen storage. The work currently is organized into four tasks: hydride development, bed fabrication, materials support for engineering systems, and IEA Annex 12 activities. At the present time, hydride development is focused on Mg alloys. These materials generally have higher weight densities for storing hydrogen than rare earth or transition metal alloys, but suffer from high operating temperatures, slow kinetic behavior and material stability. The authors approach is to study bulk alloy additions which increase equilibrium overpressure, in combination with stable surface alloy modification and particle size control to improve kinetic properties. This work attempts to build on the considerable previous research in this area, but examines specific alloy systems in greater detail, with attention to known phase properties and structures. The authors have found that specific phases can be produced which have significantly improved hydride properties compared to previous studies. 18. Functionalized heterofullerenes for hydrogen storage SciTech Connect Sun Qiang; Wang Qian; Jena, Puru 2009-01-05 Using density functional theory, we show that Li decorated B doped heterofullerene (Li{sub 12}C{sub 48}B{sub 12}) has the following desired properties of a hydrogen storage material. (1) The Li atoms remain isolated. (2) Through charge transfer to electron deficient C{sub 48}B{sub 12} heterofullerene, the Li atoms become positively charged. (3) Each Li atom is able to bind up to three H{sub 2} molecules, which remain in molecular form, and the binding energies of successive H{sub 2} molecules are in the range of 0.135-0.172 eV/H{sub 2}, suitable for ambient temperature storage. (4) The gravimetric density reaches the 9 wt % limit necessary for applications in the mobile industry. 19. Prospects for hydrogen storage in graphene. PubMed Tozzini, Valentina; Pellegrini, Vittorio 2013-01-01 Hydrogen-based fuel cells are promising solutions for the efficient and clean delivery of electricity. Since hydrogen is an energy carrier, a key step for the development of a reliable hydrogen-based technology requires solving the issue of storage and transport of hydrogen. Several proposals based on the design of advanced materials such as metal hydrides and carbon structures have been made to overcome the limitations of the conventional solution of compressing or liquefying hydrogen in tanks. Nevertheless none of these systems are currently offering the required performances in terms of hydrogen storage capacity and control of adsorption/desorption processes. Therefore the problem of hydrogen storage remains so far unsolved and it continues to represent a significant bottleneck to the advancement and proliferation of fuel cell and hydrogen technologies. Recently, however, several studies on graphene, the one-atom-thick membrane of carbon atoms packed in a honeycomb lattice, have highlighted the potentialities of this material for hydrogen storage and raise new hopes for the development of an efficient solid-state hydrogen storage device. Here we review on-going efforts and studies on functionalized and nanostructured graphene for hydrogen storage and suggest possible developments for efficient storage/release of hydrogen under ambient conditions. 20. Hydrogen storage and integrated fuel cell assembly DOEpatents Gross, Karl J. 2010-08-24 Hydrogen is stored in materials that absorb and desorb hydrogen with temperature dependent rates. A housing is provided that allows for the storage of one or more types of hydrogen-storage materials in close thermal proximity to a fuel cell stack. This arrangement, which includes alternating fuel cell stack and hydrogen-storage units, allows for close thermal matching of the hydrogen storage material and the fuel cell stack. Also, the present invention allows for tailoring of the hydrogen delivery by mixing different materials in one unit. Thermal insulation alternatively allows for a highly efficient unit. Individual power modules including one fuel cell stack surrounded by a pair of hydrogen-storage units allows for distribution of power throughout a vehicle or other electric power consuming devices. 1. Nickel hydrogen battery cell storage matrix test NASA Technical Reports Server (NTRS) Wheeler, James R.; Dodson, Gary W. 1993-01-01 Test were conducted to evaluate post storage performance of nickel hydrogen cells with various design variables, the most significant being nickel precharge versus hydrogen precharge. Test procedures and results are presented in outline and graphic form. 2. Regenerable hydrogen storage in lithium amidoborane. PubMed Tang, Ziwei; Tan, Yingbin; Chen, Xiaowei; Yu, Xuebin 2012-09-25 Regenerable hydrogen storage of lithium amidoborane is firstly achieved through the routes of direct thermal dehydrogenation and subsequent chemical hydrogenation of its dehydrogenated products by treatment with hydrazine in liquid ammonia. PMID:22875287 3. Technoeconomic comparisons of leading hydrogen storage options NASA Astrophysics Data System (ADS) Carpetis, C. The purpose of this paper is to discuss the main features of the leading options for hydrogen storage and to deliver a basic framework for technoeconomic comparisons. From the utilization point of view, several major areas of hydrogen storage (e.g., for large-scale stationary storage, transient storage, onboard storage for vehicular applications) must be considered separately. In each area, more than one storage option (gaseous, liquid, adsorbed, or adsorbed in solid materials) may be economically beneficial. Typical areas of beneficial use and restrictive features will be shown for each of the different storage options. 4. Hydrogen Storage for Aircraft Applications Overview NASA Technical Reports Server (NTRS) Colozza, Anthony J.; Kohout, Lisa (Technical Monitor) 2002-01-01 Advances in fuel cell technology have brought about their consideration as sources of power for aircraft. This power can be utilized to run aircraft systems or even provide propulsion power. One of the key obstacles to utilizing fuel cells on aircraft is the storage of hydrogen. An overview of the potential methods of hydrogen storage was compiled. This overview identifies various methods of hydrogen storage and points out their advantages and disadvantages relative to aircraft applications. Minimizing weight and volume are the key aspects to storing hydrogen within an aircraft. An analysis was performed to show how changes in certain parameters of a given storage system affect its mass and volume. 5. Polyaniline as a material for hydrogen storage applications. PubMed Attia, Nour F; Geckeler, Kurt E 2013-07-12 The main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost-effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π-electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted. 6. Hydrogen storage composition and method DOEpatents Wicks, G.G.; Heung, L.K. 1994-01-01 A hydrogen storage composition based on a metal hydride dispersed in an aerogel prepared by a sol-gel process. The starting material for the aerogel is an organometallic compound, including the alkoxysilanes, organometals of the form M(OR){sub X} where R is an organic ligand of the form C{sub n}H{sub 2n+1}, and organometals of the form MO{sub x}Ry where R is an alkyl group, where M is an oxide-forming metal, n, x and y are integers and y is two less than the valence of M. A sol is prepared by combining the starting material, alcohol, water, and an acid. The sol is conditioned to the proper viscosity and a hydride in the form of a fine powder is added. The mixture is polymerized and dried under supercritical conditions. The final product is a composition having a hydride uniformly dispersed throughout an inert, stable and highly porous matrix. It is capable of absorbing up to 30 motes of hydrogen per kilogram at room temperature and pressure, rapidly and reversibly. Hydrogen absorbed by the composition can be readily be recovered by heat or evacuation. 7. Hydrogen storage composition and method DOEpatents Heung, Leung K; Wicks, George G. 2003-01-01 A hydrogen storage composition based on a metal hydride dispersed in an aerogel prepared by a sol-gel process. The starting material for the aerogel is an organometallic compound, including the alkoxysilanes, organometals of the form M(OR)x and MOxRy, where R is an alkyl group of the form C.sub.n H.sub.2n+1, M is an oxide-forming metal, n, x, and y are integers, and y is two less than the valence of M. A sol is prepared by combining the starting material, alcohol, water, and an acid. The sol is conditioned to the proper viscosity and a hydride in the form of a fine powder is added. The mixture is polymerized and dried under supercritical conditions. The final product is a composition having a hydride uniformly dispersed throughout an inert, stable and highly porous matrix. It is capable of absorbing up to 30 moles of hydrogen per kilogram at room temperature and pressure, rapidly and reversibly. Hydrogen absorbed by the composition can be readily be recovered by heat or evacuation. 8. Amineborane Based Chemical Hydrogen Storage - Final Report SciTech Connect Sneddon, Larry G. 2011-04-21 demonstrated that H2-­release from chemical hydrides can occur by a number of different mechanistic pathways and strongly suggest that optimal chemical ­hydride based H2­release systems may require the use of synergistic dehydrogenation methods to induce H2­-loss from chemically different intermediates formed during release reactions. The efficient regeneration of ammonia borane from BNHx spent fuel is one of the most challenging problems that will have to be overcome in order to utilize AB-based hydrogen storage. Three Center partners, LANL, PNNL and Penn, each took different complimentary approaches to AB regeneration. The Penn approach focused on a strategy involving spent-fuel digestion with superacidic acids to produce boron-halides (BX3) that could then be converted to AB by coordination/reduction/displacement processes. While the Penn boron-halide reduction studies successfully demonstrated that a dialkylsulfide-based coordination/reduction/displacement process gave quantitative conversions of BBr3 to ammonia borane with efficient and safe product separations, the fact that AB spent-fuels could not be digested in good yields to BX3 halides led to a No-Go decision on this overall AB-regeneration strategy. 9. EDITORIAL: Nanoscale phenomena in hydrogen storage Nanoscale phenomena in hydrogen storage NASA Astrophysics Data System (ADS) Vajo, John; Pinkerton, Fred; Stetson, Ned 2009-05-01 Future energy technologies that use hydrogen as an energy carrier offer the tantalizing prospect of operating essentially free of pollutant and greenhouse gas emissions while utilizing hydrogen produced from a diverse range of renewable sources. To realize these technologies, such as hydrogen proton exchange membrane (PEM) fuel cells, improved approaches are needed for the high-capacity storage of hydrogen at temperatures ranging from near ambient to about 100 °C and at pressures below about 100 bar. These conditions favor storage based on the interaction of hydrogen with solid materials, rather than storage based on compressed or liquid hydrogen, which requires high pressures (700 bar) or low temperatures (20 K), respectively. Significant advances have recently been made, both in materials that store hydrogen as H2 molecules adsorbed on suitable supports and in materials that bind hydrogen chemically in the form of atoms, protons (cations) or hydride anions. Advances in molecular storage have come largely from a detailed understanding of the structures and bonding processes in traditional adsorbents and the development of new high-surface-area adsorbent materials with structures tailored on the molecular scale. Much of the emphasis has been on further increasing the number of adsorption sites to improve storage capacity. The low adsorption energies of current materials present another challenge because the weakly bound H2 can achieve technologically significant capacities only at cryogenic temperatures (50-80 K). Ongoing efforts to improve the thermodynamics of adsorption are primarily focused on composition and structure modifications. For chemically bound hydrogen, advances have come from investigation into light-element binary and complex hydrides, which inherently have high hydrogen capacities. The polar covalent bonding that characterizes these hydrides leads to very slow kinetics for hydrogen exchange, so here the emphasis is on improving kinetics through 10. Study on Hydrogen Storage Materials NASA Astrophysics Data System (ADS) Sugiyama, Jun 2016-09-01 Complex hydrides have been heavily investigated as a hydrogen storage material, particularly for future vehicular applications. The present major problem of such complex hydrides is their relatively high hydrogen desorption temperature (Td). In order to find a predominant parameter for determining Td, we have investigated internal nuclear magnetic fields in several complex hydrides, such as, lithium and sodium alanates, borohydrides, and magnesium hydrides, with a muon spin rotation and relaxation (μ+SR) technique. At low temperatures, the μ+SR spectrum obtained in a zero external field (ZF) exhibits a clear oscillation due to the formation of a three spin 1/2 system, HμH, besides Mg(BH4)2 and Sc(BH4)2. Such oscillatory signal becomes weaker and weaker with increasing temperature, and finally disappears above around room temperature. However, the volume fraction of the HμH signal to the whole asymmetry at 5 K is found to be a good indicator for Td in borohydrides. At high temperatures, on the contrary, the ZF-spectrum for MgH2 shows a Kubo-Toyabe like relaxation due to a random nuclear magnetic field of 1H. Such nuclear magnetic field becomes dynamic well below Td in the milled MgH2, indicating a significant role on H-diffusion in solids for determining Td. 11. Autothermal hydrogen storage and delivery systems DOEpatents Pez, Guido Peter; Cooper, Alan Charles; Scott, Aaron Raymond 2011-08-23 Processes are provided for the storage and release of hydrogen by means of dehydrogenation of hydrogen carrier compositions where at least part of the heat of dehydrogenation is provided by a hydrogen-reversible selective oxidation of the carrier. Autothermal generation of hydrogen is achieved wherein sufficient heat is provided to sustain the at least partial endothermic dehydrogenation of the carrier at reaction temperature. The at least partially dehydrogenated and at least partially selectively oxidized liquid carrier is regenerated in a catalytic hydrogenation process where apart from an incidental employment of process heat, gaseous hydrogen is the primary source of reversibly contained hydrogen and the necessary reaction energy. 12. Hydrogen storage and delivery system development SciTech Connect Handrock, J.L.; Wally, K.; Raber, T.N. 1995-09-01 Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. The purpose of this project is to develop a platform for the engineering evaluation of hydrogen storage and delivery systems with an added focus on lightweight hydride utilization. Hybrid vehicles represent the primary application area of interest, with secondary interests including such items as existing vehicles and stationary uses. The near term goal is the demonstration of an internal combustion engine/storage/delivery subsystem. The long term goal is optimization of storage technologies for both vehicular and industrial stationary uses. In this project an integrated approach is being used to couple system operating characteristics to hardware development. A model has been developed which integrates engine and storage material characteristics into the design of hydride storage and delivery systems. By specifying engine operating parameters, as well as a variety of storage/delivery design features, hydride bed sizing calculations are completed. The model allows engineering trade-off studies to be completed on various hydride material/delivery system configurations. A more generalized model is also being developed to allow the performance characteristics of various hydrogen storage and delivery systems to be compared (liquid, activated carbon, etc.). Many of the features of the hydride storage model are applicable to the development of this more generalized model. 13. BIMETALLIC LITHIUM BOROHYDRIDES TOWARD REVERSIBLE HYDROGEN STORAGE SciTech Connect Au, M. 2010-10-21 Borohydrides such as LiBH{sub 4} have been studied as candidates for hydrogen storage because of their high hydrogen contents (18.4 wt% for LiBH{sub 4}). Limited success has been made in reducing the dehydrogenation temperature by adding reactants such as metals, metal oxides and metal halides. However, full rehydrogenation has not been realized because of multi-step decomposition processes and the stable intermediate species produced. It is suggested that adding second cation in LiBH{sub 4} may reduce the binding energy of B-H. The second cation may also provide the pathway for full rehydrogenation. In this work, several bimetallic borohydrides were synthesized using wet chemistry, high pressure reactive ball milling and sintering processes. The investigation found that the thermodynamic stability was reduced, but the full rehydrogenation is still a challenge. Although our experiments show the partial reversibility of the bimetallic borohydrides, it was not sustainable during dehydriding-rehydriding cycles because of the accumulation of hydrogen inert species. 14. Energetics of hydrogen storage in organolithium nanostructures SciTech Connect Namilae, Sirish; Fuentes-Cabrera, Miguel A; Radhakrishnan, Balasubramaniam; Gorti, Sarma B; Nicholson, Don M 2007-01-01 Ab-initio calculations based on the second order Moller-Plesset perturbation theory (MP2) were used to investigate the interaction of molecular hydrogen with alkyl lithium organometallic compounds. It is found that lithium in organolithium structures attracts two hydrogen molecules with a binding energy of about 0.14 eV. The calculations also show that organolithium compounds bind strongly with graphitic nanostructures. Therefore, these carbon based nanostructures functionalized with organolithium compounds can be effectively used for storage of molecular hydrogen. Energetics and mechanisms for achieving high weight percent hydrogen storage in organolithium based nanostructures are discussed. 15. Hydrogen storage and delivery system development: Fabrication SciTech Connect Handrock, J.L.; Malinowski, M.E.; Wally, K. 1996-10-01 Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a newly developed fuel cell vehicle hydride storage system model will also be discussed. As an example of model use power distribution and control for a simulated driving cycle is presented. An experimental test facility, the Hydride Bed Testing Laboratory (HBTL) has been designed and fabricated. The development of this facility and its use in storage system development will be reviewed. These two capabilities (analytical and experimental) form the basis of an integrated approach to storage system design and development. The initial focus of these activities has been on hydride utilization for vehicular applications. 16. Pad B Liquid Hydrogen Storage Tank NASA Technical Reports Server (NTRS) Hall, Felicia 2007-01-01 Kennedy Space Center is home to two liquid hydrogen storage tanks, one at each launch pad of Launch Complex 39. The liquid hydrogen storage tank at Launch Pad B has a significantly higher boil off rate that the liquid hydrogen storage tank at Launch Pad A. This research looks at various calculations concerning the at Launch Pad B in an attempt to develop a solution to the excess boil off rate. We will look at Perlite levels inside the tank, Boil off rates, conductive heat transfer, and radiant heat transfer through the tank. As a conclusion to the research, we will model the effects of placing an external insulation to the tank in order to reduce the boil off rate and increase the economic efficiency of the liquid hydrogen storage tanks. 17. Hydrogen transport and storage in engineered microspheres SciTech Connect Rambach, G.; Hendricks, C. 1996-10-01 This project is a collaboration between Lawrence Livermore National Laboratory (LLNL) and W.J. Schafer Associates (WJSA). The authors plan to experimentally verify the performance characteristics of engineered glass microspheres that are relevant to the storage and transport of hydrogen for energy applications. They will identify the specific advantages of hydrogen transport by microspheres, analyze the infrastructure implications and requirements, and experimentally measure their performance characteristics in realistic, bulk storage situations. 18. Porous polymeric materials for hydrogen storage DOEpatents Yu, Luping; Liu, Di-Jia; Yuan, Shengwen; Yang, Junbing 2013-04-02 A porous polymer, poly-9,9'-spirobifluorene and its derivatives for storage of H.sub.2 are prepared through a chemical synthesis method. The porous polymers have high specific surface area and narrow pore size distribution. Hydrogen uptake measurements conducted for these polymers determined a higher hydrogen storage capacity at the ambient temperature over that of the benchmark materials. The method of preparing such polymers, includes oxidatively activating solids by CO.sub.2/steam oxidation and supercritical water treatment. 19. Carbon nanotube materials for hydrogen storage SciTech Connect Dillon, A.C.; Jones, K.M.; Heben, M.J. 1996-10-01 Hydrogen burns pollution-free and may be produced from renewable energy resources. It is therefore an ideal candidate to replace fossil fuels as an energy carrier. However, the lack of a convenient and cost-effective hydrogen storage system greatly impedes the wide-scale use of hydrogen in both domestic and international markets. Although several hydrogen storage options exist, no approach satisfies all of the efficiency, size, weight, cost and safety requirements for transportation or utility use. A material consisting exclusively of micropores with molecular dimensions could simultaneously meet all of the requirements for transportation use if the interaction energy for hydrogen was sufficiently strong to cause hydrogen adsorption at ambient temperatures. Small diameter ({approx}1 mm) carbon single-wall nanotubes (SWNTs) are elongated micropores of molecular dimensions, and materials composed predominantly of SWNTs may prove to be the ideal adsorbent for ambient temperature storage of hydrogen. Last year the authors reported that hydrogen could be adsorbed on arc-generated soots containing 12{Angstrom} diameter nanotubes at temperatures in excess of 285K. In this past year they have learned that such adsorption does not occur on activated carbon materials, and that the cobalt nanoparticles present in their arc-generated soots are not responsible for the hydrogen which is stable at 285 K. These results indicate that enhanced adsorption forces within the internal cavities of the SWNTs are active in stabilizing hydrogen at elevated temperatures. This enhanced stability could lead to effective hydrogen storage under ambient temperature conditions. In the past year the authors have also demonstrated that single-wall carbon nanotubes in arc-generated soots may be selectively opened by oxidation in H{sub 2}O resulting in improved hydrogen adsorption, and they have estimated experimentally that the amount of hydrogen stored is {approximately}10% of the nanotube weight. 20. Carbon nanotube materials from hydrogen storage SciTech Connect Dillon, A.C.; Bekkedahl, T.A.; Cahill, A.F. 1995-09-01 The lack of convenient and cost-effective hydrogen storage is a major impediment to wide scale use of hydrogen in the United States energy economy. Improvements in the energy densities of hydrogen storage systems, reductions in cost, and increased compatibility with available and forecasted systems are required before viable hydrogen energy use pathways can be established. Carbon-based hydrogen adsorption materials hold particular promise for meeting and exceeding the U.S. Department of Energy hydrogen storage energy density targets for transportation if concurrent increases in hydrogen storage capacity and carbon density can be achieved. These two goals are normally in conflict for conventional porous materials, but may be reconciled by the design and synthesis of new adsorbent materials with tailored pore size distributions and minimal macroporosity. Carbon nanotubes offer the possibility to explore new designs for adsorbents because they can be fabricated with small size distributions, and naturally tend to self-assemble by van der Waals forces. This year we report heats of adsorption for hydrogen on nanotube materials that are 2 and 3 times greater than for hydrogen on activated carbon. The hydrogen which is most strongly bound to these materials remains on the carbon surface to temperatures greater than 285 K. These results suggest that nanocapillary forces are active in stabilizing hydrogen on the surfaces of carbon nanotubes, and that optimization of the adsorbent will lead to effective storage at higher temperatures. In this paper we will also report on our activities which are targeted at understanding and optimizing the nucleation and growth of single wall nanotubes. These experiments were made possible by the development of a unique feedback control circuit which stabilized the plasma-arc during a synthesis run. 1. MXene: a new family of promising hydrogen storage medium. PubMed Hu, Qianku; Sun, Dandan; Wu, Qinghua; Wang, Haiyan; Wang, Libo; Liu, Baozhong; Zhou, Aiguo; He, Julong 2013-12-27 Searching for reversible hydrogen storage materials operated under ambient conditions is a big challenge for material scientists and chemists. In this work, using density functional calculations, we systematically investigated the hydrogen storage properties of the two-dimensional (2D) Ti2C phase, which is a representative of the recently synthesized MXene materials ( ACS Nano 2012 , 6 , 1322 ). As a constituent element of 2D Ti2C phase, the Ti atoms are fastened tightly by the strong Ti-C covalent bonds, and thus the long-standing clustering problem of transition metal does not exist. Combining with the calculated binding energy of 0.272 eV, ab initio molecular dynamic simulations confirmed the hydrogen molecules (3.4 wt % hydrogen storage capacity) bound by Kubas-type interaction can be adsorbed and released reversibly under ambient conditions. Meanwhile, the hydrogen storage properties of the other two MXene phases (Sc2C and V2C) were also evaluated, and the results were similar to those of Ti2C. Therefore, the MXene family including more than 20 members was expected to be a good candidate for reversible hydrogen storage materials under ambient conditions. 2. Improved metal hydride technology for the storage of hydrogen SciTech Connect Sapru, K.; Ming, L.; Ramachandran, S. 1995-09-01 Low cost, high density storage of hydrogen will remove the most serious barrier to large-scale utilization of hydrogen as a non-polluting, zero-emission fuel. An important challenge for the practical use of Mg-based, high capacity hydrogen storage alloys has been the development of a low-cost, bulk production technique. Two difficulties in preparation of Mg-based alloys are the immiscibility of Mg with many transition metals and the relatively high volatility of Mg compared to many transition metals. These factors preclude the use of conventional induction melting techniques for the Mg-based alloy preparation. A mechanical alloying technique, in which Mg immiscibility and volatility do not present a problem, was developed and shows great promise for production of Mg-based alloys. A number of Mg-based alloys were prepared via modified induction melting and mechanical alloying methods. The alloys were tested for gas phase hydrogen storage properties, composition, structure and morphology. The mechanically alloyed samples are multi-component, multi-phase, highly disordered materials in their as-prepared state. These unoptimized alloys have shown reversible H-storage capacity of more than 5 wt.% hydrogen. After 2000 absorption/desorption cycles, the alloys show no decline in storage capacity or desorption kinetics. The alloys have also demonstrated resistance to CH{sub 4} and CO poisoning in preliminary testing. Upon annealing, with an increase in crystallinity, the H-storage capacity decreases, indicating the importance of disorder. 3. Hydrogen storage and delivery system development: Analysis SciTech Connect Handrock, J.L. 1996-10-01 Hydrogen storage and delivery is an important element in effective hydrogen utilization for energy applications and is an important part of the FY1994-1998 Hydrogen Program Implementation Plan. This project is part of the Field Work Proposal entitled Hydrogen Utilization in Internal Combustion Engines (ICE). The goal of the Hydrogen Storage and Delivery System Development Project is to expand the state-of-the-art of hydrogen storage and delivery system design and development. At the foundation of this activity is the development of both analytical and experimental evaluation platforms. These tools provide the basis for an integrated approach for coupling hydrogen storage and delivery technology to the operating characteristics of potential hydrogen energy use applications. Results of the analytical model development portion of this project will be discussed. Analytical models have been developed for internal combustion engine (ICE) hybrid and fuel cell driven vehicles. The dependence of hydride storage system weight and energy use efficiency on engine brake efficiency and exhaust temperature for ICE hybrid vehicle applications is examined. Results show that while storage system weight decreases with increasing engine brake efficiency energy use efficiency remains relatively unchanged. The development, capability, and use of a recently developed fuel cell vehicle storage system model will also be discussed. As an example of model use, power distribution and control for a simulated driving cycle is presented. Model calibration results of fuel cell fluid inlet and exit temperatures at various fuel cell idle speeds, assumed fuel cell heat capacities, and ambient temperatures are presented. The model predicts general increases in temperature with fuel cell power and differences between inlet and exit temperatures, but under predicts absolute temperature values, especially at higher power levels. 4. LIGHT-WEIGHT NANOCRYSTALLINE HYDROGEN STORAGE MATERIALS SciTech Connect S. G. Sankar; B. Zande; R.T. Obermyer; S. Simizu 2005-11-21 During Phase I of this SBIR Program, Advanced Materials Corporation has addressed two key issues concerning hydrogen storage: 1. We have conducted preliminary studies on the effect of certain catalysts in modifying the hydrogen absorption characteristics of nanocrystalline magnesium. 2. We have also conducted proof-of-concept design and construction of a prototype instrument that would rapidly screen materials for hydrogen storage employing chemical combinatorial technique in combination with a Pressure-Composition Isotherm Measurement (PCI) instrument. 3. Preliminary results obtained in this study approach are described in this report. 5. Microcavity hydrogen storage. Final progress report SciTech Connect Teitel, R. J. 1981-05-01 In the microcavity storage system, high pressure hydrogen is stored in hollow, glass microspheres, 5 to 150 ..mu..m. This report presents the results of an experimental study to evaluate the performance of commercially available microspheres for this application. Eight grades were evaluated and their characteristics are presented. A substantial fraction of the microsphere beds survived the conditions of storing hydrogen at pressures of 400 atm. establishing that the concept of high pressure hydrogen storage is feasible. Information was gathered on the properties of the survivor microspheres. Processes for their selective recovery are being investigated. 6. HGMS: Glasses and Nanocomposites for Hydrogen Storage. SciTech Connect Lipinska, Kris; Hemmers, Oliver 2013-02-17 The primary goal of this project is to fabricate and investigate different glass systems and glass-derived nanocrystalline composite materials. These glass-based, two-phased materials will contain nanocrystals that can attract hydrogen and be of potential interest as hydrogen storage media. The glass materials with intrinsic void spaces that are able to precipitate functional nanocrystals capable to attract hydrogen are of particular interest. Proposed previously, but never practically implemented, one of promising concepts for storing hydrogen are micro-containers built of glass and shaped into hollow microspheres. The project expanded this concept to the exploration of glass-derived nanocrystalline composites as potential hydrogen storage media. It is known that the most desirable materials for hydrogen storage do not interact chemically with hydrogen and possess a high surface area to host substantial amounts of hydrogen. Glasses are built of disordered networks with ample void spaces that make them permeable to hydrogen even at room temperature. Glass-derived nanocrystalline composites (two-phased materials), combination of glasses (networks with ample voids) and functional nanocrystals (capable to attract hydrogen), appear to be promising candidates for hydrogen storage media. Key advantages of glass materials include simplicity of preparation, flexibility of composition, chemical durability, non-toxicity and mechanical strength, as well as low production costs and environmental friendliness. This project encompasses a fundamental research into physics and chemistry of glasses and nanocrystalline composite materials, derived from glass. Studies are aimed to answer questions essential for considering glass-based materials and composites as potential hydrogen storage media. Of particular interest are two-phased materials that combine glasses with intrinsic voids spaces for physisorption of hydrogen and nanocrystals capable of chemisorption. This project does not 7. Performance of a full-scale hydrogen-storage tank based on complex hydrides. PubMed Johnson, Terry A; Jorgensen, Scott W; Dedrick, Daniel E 2011-01-01 Designing and building a full scale hydrogen storage system revealed several engineering challenges and also demonstrated the capabilities of complex hydrides. Three kg of hydrogen was stored in a four module system using modified sodium alanate as the storage media. Extensive testing of this system demonstrated the ability to follow aggressive hydrogen demand schedules that simulate actual driving. Extensive use of detailed models greatly improved the design and eventual performance of the storage system; the test data permitted further refinement of the models. 8. Final Report: Metal Perhydrides for Hydrogen Storage SciTech Connect Hwang, J-Y.; Shi, S.; Hackney, S.; Swenson, D.; Hu, Y. 2011-07-26 Hydrogen is a promising energy source for the future economy due to its environmental friendliness. One of the important obstacles for the utilization of hydrogen as a fuel source for applications such as fuel cells is the storage of hydrogen. In the infrastructure of the expected hydrogen economy, hydrogen storage is one of the key enabling technologies. Although hydrogen possesses the highest gravimetric energy content (142 KJ/g) of all fuels, its volumetric energy density (8 MJ/L) is very low. It is desired to increase the volumetric energy density of hydrogen in a system to satisfy various applications. Research on hydrogen storage has been pursed for many years. Various storage technologies, including liquefaction, compression, metal hydride, chemical hydride, and adsorption, have been examined. Liquefaction and high pressure compression are not desired due to concerns related to complicated devices, high energy cost and safety. Metal hydrides and chemical hydrides have high gravimetric and volumetric energy densities but encounter issues because high temperature is required for the release of hydrogen, due to the strong bonding of hydrogen in the compounds. Reversibility of hydrogen loading and unloading is another concern. Adsorption of hydrogen on high surface area sorbents such as activated carbon and organic metal frameworks does not have the reversibility problem. But on the other hand, the weak force (primarily the van der Waals force) between hydrogen and the sorbent yields a very small amount of adsorption capacity at ambient temperature. Significant storage capacity can only be achieved at low temperatures such as 77K. The use of liquid nitrogen in a hydrogen storage system is not practical. Perhydrides are proposed as novel hydrogen storage materials that may overcome barriers slowing advances to a hydrogen fuel economy. In conventional hydrides, e.g. metal hydrides, the number of hydrogen atoms equals the total valence of the metal ions. One Li 9. Hydrogen storage on activated carbon. Final report SciTech Connect Schwarz, J.A. 1994-11-01 The project studied factors that influence the ability of carbon to store hydrogen and developed techniques to enhance that ability in naturally occurring and factory-produced commercial carbon materials. During testing of enhanced materials, levels of hydrogen storage were achieved that compare well with conventional forms of energy storage, including lead-acid batteries, gasoline, and diesel fuel. Using the best materials, an electric car with a modern fuel cell to convert the hydrogen directly to electricity would have a range of over 1,000 miles. This assumes that the total allowable weight of the fuel cell and carbon/hydrogen storage system is no greater than the present weight of batteries in an existing electric vehicle. By comparison, gasoline cars generally are limited to about a 450-mile range, and battery-electric cars to 40 to 60 miles. The project also developed a new class of carbon materials, based on polymers and other organic compounds, in which the best hydrogen-storing factors discovered earlier were {open_quotes}molecularly engineered{close_quotes} into the new materials. It is believed that these new molecularly engineered materials are likely to exceed the performance of the naturally occurring and manufactured carbons seen earlier with respect to hydrogen storage. 10. Methyllithium-Doped Naphthyl-Containing Conjugated Microporous Polymer with Enhanced Hydrogen Storage Performance. PubMed Xu, Dan; Sun, Lei; Li, Gang; Shang, Jin; Yang, Rui-Xia; Deng, Wei-Qiao 2016-06-01 Hydrogen storage is a primary challenge for using hydrogen as a fuel. With ideal hydrogen storage kinetics, the weak binding strength of hydrogen to sorbents is the key barrier to obtain decent hydrogen storage performance. Here, we reported the rational synthesis of a methyllithium-doped naphthyl-containing conjugated microporous polymer with exceptional binding strength of hydrogen to the polymer guided by theoretical simulations. Meanwhile, the experimental results showed that isosteric heat can reach up to 8.4 kJ mol(-1) and the methyllithium-doped naphthyl-containing conjugated microporous polymer exhibited an enhanced hydrogen storage performance with 150 % enhancement compared with its counterpart naphthyl-containing conjugated microporous polymer. These results indicate that this strategy provides a direction for design and synthesis of new materials that meet the US Department of Energy (DOE) hydrogen storage target. 11. Simultaneous purification and storage of hydrogen SciTech Connect Hynek, S.; Fuller, W.; Weber, R.; Carlson, E. 1998-08-01 Specially coated magnesium particles have been shown to selectively absorb hydrogen from a hydrogen-rich gas stream such as reformate. These coated magnesium particles can store the absorbed hydrogen as required and subsequently deliver pure hydrogen, just as uncoated magnesium particles can. These coated magnesium particles could be used in a device that accepts a steady stream of reformate, as from a methane reformer, stores the selectively absorbed hydrogen indefinitely, and delivers purified hydrogen on demand. Unfortunately, this coating (magnesium nitride) has been shown to degrade over a period of several weeks, so that the magnesium within evidences progressively lower storage capacity. The authors are investigating two other coatings, one of which might be applicable to hydridable metals other than magnesium, to replace magnesium nitride. 12. Hydrogen Storage and Production Project SciTech Connect Bhattacharyya, Abhijit; Biris, A. S.; Mazumder, M. K.; Karabacak, T.; Kannarpady, Ganesh; Sharma, R. 2011-07-31 This is the final technical report. This report is a summary of the project. The goal of our project is to improve solar-to-hydrogen generation efficiency of the PhotoElectroChemical (PEC) conversion process by developing photoanodes with high absorption efficiency in the visible region of the solar radiation spectrum and to increase photo-corrosion resistance of the electrode for generating hydrogen from water. To meet this goal, we synthesized nanostructured heterogeneous semiconducting photoanodes with a higher light absorption efficiency compared to that of TiO2 and used a corrosion protective layer of TiO2. While the advantages of photoelectrochemical (PEC) production of hydrogen have not yet been realized, the recent developments show emergence of new nanostructural designs of photoanodes and choices of materials with significant gains in photoconversion efficiency. 13. HYDROGEN DELIVERY: INFRASTRUCTURE, CHALLENGES, AND MATERIALS NEEDS SciTech Connect Pawel, Steven J; Gardiner, Monterey 2009-01-01 Current domestic energy policy is aimed at encouraging the development of alternative fuels such as hydrogen for use as a renewable and environmentally-friendly alternative to traditional petroleum-based fuels for transportation and stationary power. The purpose of the Hydrogen Delivery Technical Team is to provide insight and input on hydrogen delivery infrastructure research. Ongoing research has identified materials R&D challenges required to support this infrastructure. A few of these challenges are summarized with emphasis placed on materials. 14. Porous polymeric materials for hydrogen storage DOEpatents Yu, Luping; Liu, Di-Jia; Yuan, Shengwen; Yang, Junbing 2011-12-13 Porous polymers, tribenzohexazatriphenylene, poly-9,9'-spirobifluorene, poly-tetraphenyl methane and their derivatives for storage of H.sub.2 prepared through a chemical synthesis method. The porous polymers have high specific surface area and narrow pore size distribution. Hydrogen uptake measurements conducted for these polymers determined a higher hydrogen storage capacity at the ambient temperature over that of the benchmark materials. The method of preparing such polymers, includes oxidatively activating solids by CO.sub.2/steam oxidation and supercritical water treatment. 15. Multi-component hydrogen storage material DOEpatents Faheem, Syed A.; Lewis, Gregory J.; Sachtler, J.W. Adriaan; Low, John J.; Lesch, David A.; Dosek, Paul M.; Wolverton, Christopher M.; Siegel, Donald J.; Sudik, Andrea C.; Yang, Jun 2010-09-07 A reversible hydrogen storage composition having an empirical formula of: Li.sub.(x+z)N.sub.xMg.sub.yB.sub.zH.sub.w where 0.4.ltoreq.x.ltoreq.0.8; 0.2.ltoreq.y.ltoreq.0.6; 0hydrogen storage compared to binary systems such as MgH.sub.2--LiNH.sub.2. 16. Capacity retention in hydrogen storage alloys NASA Technical Reports Server (NTRS) Anani, A.; Visintin, A.; Srinivasan, S.; Appleby, A. J.; Reilly, J. J.; Johnson, J. R. 1992-01-01 Results of our examination of the properties of several candidate materials for hydrogen storage electrodes and their relation to the decrease in H-storage capacity upon open-circuit storage over time are reported. In some of the alloy samples examined to date, only about 10 percent of the hydrogen capacity was lost upon storage for 20 days, while in others, this number was as high as 30 percent for the same period of time. This loss in capacity is attributed to two separate mechanisms: (1) hydrogen desorbed from the electrode due to pressure differences between the cell and the electrode sample; and (2) chemical and/or electrochemical degradation of the alloy electrode upon exposure to the cell environment. The former process is a direct consequence of the equilibrium dissociation pressure of the hydride alloy phase and the partial pressure of hydrogen in the hydride phase in equilibrium with that in the electrolyte environment, while the latter is related to the stability of the alloy phase in the cell environment. Comparison of the equilibrium gas-phase dissociation pressures of these alloys indicate that reversible loss of hydrogen capacity is higher in alloys with P(eqm) greater than 1 atm than in those with P(eqm) less than 1 atm. 17. Hydrogen storage in graphite nanofibers SciTech Connect Park, C.; Tan, C.D.; Hidalgo, R.; Baker, R.T.K.; Rodriguez, N.M. 1998-08-01 Graphite nanofibers (GNF) are a type of material that is produced by the decomposition of carbon containing gases over metal catalyst particles at temperatures around 600 C. These molecularly engineered structures consist of graphene sheets perfectly arranged in a parallel, perpendicular or at angle orientation with respect to the fiber axis. The most important feature of the material is that only edges are exposed. Such an arrangement imparts the material with unique properties for gas adsorption because the evenly separated layers constitute the most ordered set of nanopores that can accommodate an adsorbate in the most efficient manner. In addition, the non-rigid pore walls can also expand so as to accommodate hydrogen in a multilayer conformation. Of the many varieties of structures that can be produced the authors have discovered that when gram quantities of a selected number of GNF are exposed to hydrogen at pressures of {approximately} 2,000 psi, they are capable of adsorbing and storing up to 40 wt% of hydrogen. It is believed that a strong interaction is established between hydrogen and the delocalized p-electrons present in the graphite layers and therefore a new type of chemistry is occurring within these confined structures. 18. Hydrogen and fuel cells for energy storage NASA Astrophysics Data System (ADS) Lund, P. The first Nordic Symposium on Hydrogen and Fuel Cells for Energy Storage was held on March 11-12, 1993 at the premises of the Helsinki University of Technology in Espoo-Otaniemi. The initiator and main sponsor of this Symposium was the Nordic Energy Research Program and its Committee for Fuel Cells. The major objective of the seminar was to present recent developments and research activities on the use of hydrogen and fuel cells for energy storage purposes. Emphasis was laid on smaller systems applicable, e.g., for autonomous energy production. Hydrogen storage, conversion of hydrogen into final energy, and on-site production of hydrogen, e.g., by renewable energy sources were considered. Besides basic scientific issues and components; system technology aspects were also discussed. New areas for further Nordic cooperation were identified during the symposium. The seminar was attended by almost 60 persons from all Nordic countries. Furthermore, three world-known scientists gave their overview on the status and trends of the hydrogen technology. This proceeding comprises the papers presented at the symposium. 19. Activated aluminum hydride hydrogen storage compositions and uses thereof DOEpatents Sandrock, Gary; Reilly, James; Graetz, Jason; Wegrzyn, James E. 2010-11-23 In one aspect, the invention relates to activated aluminum hydride hydrogen storage compositions containing aluminum hydride in the presence of, or absence of, hydrogen desorption stimulants. The invention particularly relates to such compositions having one or more hydrogen desorption stimulants selected from metal hydrides and metal aluminum hydrides. In another aspect, the invention relates to methods for generating hydrogen from such hydrogen storage compositions. 20. Hydrogen storage in metal-hydrogen systems and their derivatives NASA Astrophysics Data System (ADS) Eberle, U.; Arnold, G.; von Helmolt, R. During the last years, the power densities of automotive fuel cell systems have been raised dramatically. However, a major technology improvement is still needed for the on-board fuel storage system since hydrogen exhibits a rather low volumetric energy density (regardless whether it is stored as a liquid at cryogenic temperatures or as a compressed gas). Furthermore, the cost for current hydrogen containers is far from what gasoline tanks cost. Therefore, alternatives like solid-state absorbers of hydrogen (e.g. metal hydrides or complex hydrides) are investigated for their feasibility by the car industry. These kinds of systems show very high volumetric storage densities on a materials basis. Unfortunately, the host compounds are usually quite heavy and thus possess a low gravimetric storage density. Also, the thermodynamics and kinetics of the absorption/desorption reactions and their impact on the tank design in general (and on the heat management in particular) have to be considered. Within the framework of this paper, the properties of the most promising solid-state storage systems are discussed and compared to those of the liquid and compressed gaseous hydrogen technologies. 1. Hydrogen storage via polyhydride complexes SciTech Connect Jensen, C.M.; Zidan, R.A. 1998-08-01 The reversible dehydrogenation of NaAlH{sub 4} is catalyzed in toluene slurries of the NaAlH{sub 4} containing the pincer complex, IrH{sub 4} {l_brace}C{sub 6}H{sub 3}-2,6-(CH{sub 2}PBu{sup t}{sub 2}){sub 2}{r_brace}. The rates of the pincer complex catalyzed dehydrogenation are about five times greater those previously found for NaAlH{sub 4} that was doped with titanium through a wet chemistry method. Homogenization of NaAlH{sub 4} with 2 mole % Ti(OBu{sup n}){sub 4} under an atmosphere of argon produces a novel titanium containing material. TPD measurements show that the dehydrogenation of this material occurs about 30 C lower than that previously found for wet titanium doped NaAlH{sub 4}. In further contrast to wet doped NaAlH{sub 4}, the dehydrogenation kinetics and hydrogen capacity of the novel material are undiminished over several dehydriding/hydriding cycles. Rehydrogenation of the titanium doped material occurs readily at 170 C under 150 atm of hydrogen. TPD measurements show that about 80% of the original hydrogen content (4.2 wt%) can be restored under these conditions. 2. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE SciTech Connect Fewox, C; Ragaiy Zidan, R; Brenda Garcia-Diaz, B 2008-12-31 Hydrogen storage is one of the greatest challenges for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods; the direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum. 3. ALUMINUM HYDRIDE: A REVERSIBLE MATERIAL FOR HYDROGEN STORAGE SciTech Connect Zidan, R; Christopher Fewox, C; Brenda Garcia-Diaz, B; Joshua Gray, J 2009-01-09 Hydrogen storage is one of the challenges to be overcome for implementing the ever sought hydrogen economy. Here we report a novel cycle to reversibly form high density hydrogen storage materials such as aluminium hydride. Aluminium hydride (AlH{sub 3}, alane) has a hydrogen storage capacity of 10.1 wt% H{sub 2}, 149 kg H{sub 2}/m{sup 3} volumetric density and can be discharged at low temperatures (< 100 C). However, alane has been precluded from use in hydrogen storage systems because of the lack of practical regeneration methods. The direct hydrogenation of aluminium to form AlH{sub 3} requires over 10{sup 5} bars of hydrogen pressure at room temperature and there are no cost effective synthetic means. Here we show an unprecedented reversible cycle to form alane electrochemically, using alkali metal alanates (e.g. NaAlH{sub 4}, LiAlH{sub 4}) in aprotic solvents. To complete the cycle, the starting alanates can be regenerated by direct hydrogenation of the dehydrided alane and the alkali hydride being the other compound formed in the electrochemical cell. The process of forming NaAlH{sub 4} from NaH and Al is well established in both solid state and solution reactions. The use of adducting Lewis bases is an essential part of this cycle, in the isolation of alane from the mixtures of the electrochemical cell. Alane is isolated as the triethylamine (TEA) adduct and converted to pure, unsolvated alane by heating under vacuum. 4. Standardized Testing Program for Solid-State Hydrogen Storage Technologies SciTech Connect Miller, Michael A.; Page, Richard A. 2012-07-30 In the US and abroad, major research and development initiatives toward establishing a hydrogen-based transportation infrastructure have been undertaken, encompassing key technological challenges in hydrogen production and delivery, fuel cells, and hydrogen storage. However, the principal obstacle to the implementation of a safe, low-pressure hydrogen fueling system for fuel-cell powered vehicles remains storage under conditions of near-ambient temperature and moderate pressure. The choices for viable hydrogen storage systems at the present time are limited to compressed gas storage tanks, cryogenic liquid hydrogen storage tanks, chemical hydrogen storage, and hydrogen absorbed or adsorbed in a solid-state material (a.k.a. solid-state storage). Solid-state hydrogen storage may offer overriding benefits in terms of storage capacity, kinetics and, most importantly, safety.The fervor among the research community to develop novel storage materials had, in many instances, the unfortunate consequence of making erroneous, if not wild, claims on the reported storage capacities achievable in such materials, to the extent that the potential viability of emerging materials was difficult to assess. This problem led to a widespread need to establish a capability to accurately and independently assess the storage behavior of a wide array of different classes of solid-state storage materials, employing qualified methods, thus allowing development efforts to focus on those materials that showed the most promise. However, standard guidelines, dedicated facilities, or certification programs specifically aimed at testing and assessing the performance, safety, and life cycle of these emergent materials had not been established. To address the stated need, the Testing Laboratory for Solid-State Hydrogen Storage Technologies was commissioned as a national-level focal point for evaluating new materials emerging from the designated Materials Centers of Excellence (MCoE) according to 5. Flexible bulb large storage box hydrogen maser NASA Technical Reports Server (NTRS) Reinhardt, V. 1973-01-01 The principal limitation on the accuracy of the hydrogen maser as a primary frequency standard has been the irreproducibility of the frequency shift caused by collisions of the radiating atoms with the walls of the vessel containing them. The flexible bulb-large storage box hydrogen maser allows correction for this wall shift within a single device, sidestepping the reproducibility problem, and reducing the frequency error from the wall shift to the level imposed by the device's stability. The principles of the device are discussed including the flexible bulb technique and the complications caused by a multiple region storage bulb. The stability of the device is discussed including a comparison with an ordinary hydrogen maser. Data is presented from a working flexible bulb-large storage box hydrogen maser demonstrating the feasibility of the device and showing some of its operating characteristics. The flexibility of the device is demonstrated by showing how the device's added degrees of freedom allow measurement of parameters unmeasurable in an ordinary hydrogen maser. 6. Nanomaterials for Hydrogen Storage Applications: A Review DOE PAGES Niemann, Michael U.; Srinivasan, Sesha S.; Phani, Ayala R.; Kumar, Ashok; Goswami, D. Yogi; Stefanakos, Elias K. 2008-01-01 Nmore » anomaterials have attracted great interest in recent years because of the unusual mechanical, electrical, electronic, optical, magnetic and surface properties. The high surface/volume ratio of these materials has significant implications with respect to energy storage. Both the high surface area and the opportunity for nanomaterial consolidation are key attributes of this new class of materials for hydrogen storage devices.anostructured systems including carbon nanotubes, nano-magnesium based hydrides, complex hydride/carbon nanocomposites, boron nitride nanotubes, TiS 2 / MoS 2 nanotubes, alanates, polymer nanocomposites, and metal organic frameworks are considered to be potential candidates for storing large quantities of hydrogen. Recent investigations have shown that nanoscale materials may offer advantages if certain physical and chemical effects related to the nanoscale can be used efficiently. The present review focuses the application of nanostructured materials for storing atomic or molecular hydrogen. The synergistic effects of nanocrystalinity and nanocatalyst doping on the metal or complex hydrides for improving the thermodynamics and hydrogen reaction kinetics are discussed. In addition, various carbonaceous nanomaterials and novel sorbent systems (e.g. carbon nanotubes, fullerenes, nanofibers, polyaniline nanospheres and metal organic frameworks etc.) and their hydrogen storage characteristics are outlined.« less 7. Modeling leaks from liquid hydrogen storage systems. SciTech Connect Winters, William Stanley, Jr. 2009-01-01 This report documents a series of models for describing intended and unintended discharges from liquid hydrogen storage systems. Typically these systems store hydrogen in the saturated state at approximately five to ten atmospheres. Some of models discussed here are equilibrium-based models that make use of the NIST thermodynamic models to specify the states of multiphase hydrogen and air-hydrogen mixtures. Two types of discharges are considered: slow leaks where hydrogen enters the ambient at atmospheric pressure and fast leaks where the hydrogen flow is usually choked and expands into the ambient through an underexpanded jet. In order to avoid the complexities of supersonic flow, a single Mach disk model is proposed for fast leaks that are choked. The velocity and state of hydrogen downstream of the Mach disk leads to a more tractable subsonic boundary condition. However, the hydrogen temperature exiting all leaks (fast or slow, from saturated liquid or saturated vapor) is approximately 20.4 K. At these temperatures, any entrained air would likely condense or even freeze leading to an air-hydrogen mixture that cannot be characterized by the REFPROP subroutines. For this reason a plug flow entrainment model is proposed to treat a short zone of initial entrainment and heating. The model predicts the quantity of entrained air required to bring the air-hydrogen mixture to a temperature of approximately 65 K at one atmosphere. At this temperature the mixture can be treated as a mixture of ideal gases and is much more amenable to modeling with Gaussian entrainment models and CFD codes. A Gaussian entrainment model is formulated to predict the trajectory and properties of a cold hydrogen jet leaking into ambient air. The model shows that similarity between two jets depends on the densimetric Froude number, density ratio and initial hydrogen concentration. 8. NREL Advances Spillover Materials for Hydrogen Storage (Fact Sheet) SciTech Connect Not Available 2010-12-01 This fact sheet describes NREL's accomplishments in advancing spillover materials for hydrogen storage and improving the reproducible synthesis, long-term durability, and material costs of hydrogen storage materials. Work was performed by NREL's Chemical and Materials Science Center. 9. Systems Engineering of Chemical Hydrogen Storage, Pressure Vessel and Balance of Plant for Onboard Hydrogen Storage SciTech Connect Brooks, Kriston P.; Simmons, Kevin L.; Weimar, Mark R. 2014-09-02 This is the annual report for the Hydrogen Storage Engineering Center of Excellence project as required by DOE EERE's Fuel Cell Technologies Office. We have been provided with a specific format. It describes the work that was done with cryo-sorbent based and chemical-based hydrogen storage materials. Balance of plant components were developed, proof-of-concept testing performed, system costs estimated, and transient models validated as part of this work. 10. Redox Flow Batteries, Hydrogen and Distributed Storage. PubMed Dennison, C R; Vrubel, Heron; Amstutz, Véronique; Peljo, Pekka; Toghill, Kathryn E; Girault, Hubert H 2015-01-01 Social, economic, and political pressures are causing a shift in the global energy mix, with a preference toward renewable energy sources. In order to realize widespread implementation of these resources, large-scale storage of renewable energy is needed. Among the proposed energy storage technologies, redox flow batteries offer many unique advantages. The primary limitation of these systems, however, is their limited energy density which necessitates very large installations. In order to enhance the energy storage capacity of these systems, we have developed a unique dual-circuit architecture which enables two levels of energy storage; first in the conventional electrolyte, and then through the formation of hydrogen. Moreover, we have begun a pilot-scale demonstration project to investigate the scalability and technical readiness of this approach. This combination of conventional energy storage and hydrogen production is well aligned with the current trajectory of modern energy and mobility infrastructure. The combination of these two means of energy storage enables the possibility of an energy economy dominated by renewable resources. PMID:26842325 11. Hydrogen Storage in Metal-Organic Frameworks SciTech Connect Omar M. Yaghi 2012-04-26 Conventional storage of large amounts of hydrogen in its molecular form is difficult and expensive because it requires employing either extremely high pressure gas or very low temperature liquid. Because of the importance of hydrogen as a fuel, the DOE has set system targets for hydrogen storage of gravimetric (5.5 wt%) and volumetric (40 g L-1) densities to be achieved by 2015. Given that these are system goals, a practical material will need to have higher capacity when the weight of the tank and associated cooling or regeneration system is considered. The size and weight of these components will vary substantially depending on whether the material operates by a chemisorption or physisorption mechanism. In the latter case, metal-organic frameworks (MOFs) have recently been identified as promising adsorbents for hydrogen storage, although little data is available for their sorption behavior. This grant was focused on the study of MOFs with these specific objectives. (1) To examine the effects of functionalization, catenation, and variation of the metal oxide and organic linkers on the low-pressure hydrogen adsorption properties of MOFs. (2) To develop a strategy for producing MOFs with high surface area and porosity to reduce the dead space and increase the hydrogen storage capacity per unit volume. (3) To functionalize MOFs by post synthetic functionalization with metals to improve the adsorption enthalpy of hydrogen for the room temperature hydrogen storage. This effort demonstrated the importance of open metal sites to improve the adsorption enthalpy by the systematic study, and this is also the origin of the new strategy, which termed isoreticular functionalization and metalation. However, a large pore volume is still a prerequisite feature. Based on our principle to design highly porous MOFs, guest-free MOFs with ultrahigh porosity have been experimentally synthesized. MOF-210, whose BET surface area is 6240 m2 g-1 (the highest among porous solids), takes up 12. Integrated Refrigeration and Storage for Advanced Liquid Hydrogen Operations NASA Technical Reports Server (NTRS) Swanger, A. M.; Notardonato, W. U.; Johnson, W. L.; Tomsik, T. M. 2016-01-01 NASA has used liquefied hydrogen (LH2) on a large scale since the beginning of the space program as fuel for the Centaur and Apollo upper stages, and more recently to feed the three space shuttle main engines. The LH2 systems currently in place at the Kennedy Space Center (KSC) launch pads are aging and inefficient compared to the state-of-the-art. Therefore, the need exists to explore advanced technologies and operations that can drive commodity costs down, and provide increased capabilities. The Ground Operations Demonstration Unit for Liquid Hydrogen (GODU-LH2) was developed at KSC to pursue these goals by demonstrating active thermal control of the propellant state by direct removal of heat using a cryocooler. The project has multiple objectives including zero loss storage and transfer, liquefaction of gaseous hydrogen, and densification of liquid hydrogen. The key technology challenge was efficiently integrating the cryogenic refrigerator into the LH2 storage tank. A Linde LR1620 Brayton cycle refrigerator is used to produce up to 900W cooling at 20K, circulating approximately 22 g/s gaseous helium through the hydrogen via approximately 300 m of heat exchanger tubing. The GODU-LH2 system is fully operational, and is currently under test. This paper will discuss the design features of the refrigerator and storage system, as well as the current test results. 13. Nanodiamond for hydrogen storage: temperature-dependent hydrogenation and charge-induced dehydrogenation. PubMed Lai, Lin; Barnard, Amanda S 2012-02-21 Carbon-based hydrogen storage materials are one of hottest research topics in materials science. Although the majority of studies focus on highly porous loosely bound systems, these systems have various limitations including use at elevated temperature. Here we propose, based on computer simulations, that diamond nanoparticles may provide a new promising high temperature candidate with a moderate storage capacity, but good potential for recyclability. The hydrogenation of nanodiamonds is found to be easily achieved, in agreement with experiments, though we find the stability of hydrogenation is dependent on the morphology of nanodiamonds and surrounding environment. Hydrogenation is thermodynamically favourable even at high temperature in pure hydrogen, ammonia, and methane gas reservoirs, whereas water vapour can help to reduce the energy barrier for desorption. The greatest challenge in using this material is the breaking of the strong covalent C-H bonds, and we have identified that the spontaneous release of atomic hydrogen may be achieved through charging of hydrogenated nanodiamonds. If the degree of induced charge is properly controlled, the integrity of the host nanodiamond is maintained, which indicates that an efficient and recyclable approach for hydrogen release may be possible. PMID:22089370 14. Halloysite nanotubes as hydrogen storage materials NASA Astrophysics Data System (ADS) Jin, Jiao; Zhang, Yi; Ouyang, Jing; Yang, Huaming 2014-05-01 The hydrogen adsorption capacities of halloysite nanotubes (HNTs), subjected to different treatments, were investigated at room temperature. The three different treatments included thermal, acid, and palladium modification. The hydrogen adsorption capacity of the HNTs was 0.436 % at 2.63 MPa and 298 K whereas those of the thermally treated HNTs, palladium-modified HNTs (Pd-HNTs), and acid-treated HNTs (A-HNTs), under the same conditions, were 0.263, 1.143, and 1.371 %, respectively. The hydrogen adsorption capacities of both HNTs and treated HNTs are among the highest values reported in the literature so far. Large surface areas were advantageous in promoting hydrogen adsorption via a physisorption mechanism, which was directly related to the aluminosilicate structure of HNTs. It was also possible to enhance the hydrogen adsorption capacity through a chemisorption or spillover mechanism by modifying HNTs with Pd. The HNTs and treated HNTs show potential as physisorption-based mediums for hydrogen storage at room temperature, in particular HNTs and A-HNTs show excellent stability and high hydrogen adsorption capacities. 15. Ford/BASF/UM Activities in Support of the Hydrogen Storage Engineering Center of Excellence SciTech Connect Veenstra, Mike; Purewal, Justin; Xu, Chunchuan; Yang, Jun; Blaser, Rachel; Sudik, Andrea; Siegel, Don; Ming, Yang; Liu, Dong'an; Chi, Hang; Gaab, Manuela; Arnold, Lena; Muller, Ulrich 2015-06-30 Widespread adoption of hydrogen as a vehicular fuel depends critically on the development of low-cost, on-board hydrogen storage technologies capable of achieving high energy densities and fast kinetics for hydrogen uptake and release. As present-day technologies -- which rely on physical storage methods such as compressed hydrogen -- are incapable of attaining established Department of Energy (DOE) targets, development of materials-based approaches for storing hydrogen have garnered increasing attention. Material-based storage technologies have potential to store hydrogen beyond twice the density of liquid hydrogen. To hasten development of these ‘hydride’ materials, the DOE previously established three centers of excellence for materials storage R&D associated with the key classes of materials: metal hydrides, chemical hydrogen, and adsorbents. While these centers made progress in identifying new storage materials, the challenges associated with the engineering of the system around a candidate storage material are in need of further advancement. In 2009 the DOE established the Hydrogen Storage Engineering Center of Excellence with the objective of developing innovative engineering concepts for materials-based hydrogen storage systems. As a partner in the Hydrogen Storage Engineering Center of Excellence, the Ford-UM-BASF team conducted a multi-faceted research program that addresses key engineering challenges associated with the development of materials-based hydrogen storage systems. First, we developed a novel framework that allowed for a material-based hydrogen storage system to be modeled and operated within a virtual fuel cell vehicle. This effort resulted in the ability to assess dynamic operating parameters and interactions between the storage system and fuel cell power plant, including the evaluation of performance throughout various drive cycles. Second, we engaged in cost modeling of various incarnations of the storage systems. This analysis 16. Nickel-hydrogen capacity loss on storage NASA Technical Reports Server (NTRS) Manzo, Michelle A. 1989-01-01 A controlled experiment evaluating the capacity loss experienced by nickel electrodes stored under various conditions of temperature, hydrogen pressure, and electrolyte concentration was conducted using nickel electrodes from four different manufacturers. It was found that capacity loss varied with respect to hydrogen pressure, and storage temperature as well as with respect to electrode manufacturing processes. Impedance characteristics were monitored and found to be indicative of electrode manufacturing processes and capacity loss. Cell testing to evaluate state-of-charge effects on capacity loss were inconclusive as no loss was sustained by the cells tested in this experiment. 17. Hydrogen-storage materials for mobile applications NASA Astrophysics Data System (ADS) Schlapbach, Louis; Züttel, Andreas 2001-11-01 Mobility - the transport of people and goods - is a socioeconomic reality that will surely increase in the coming years. It should be safe, economic and reasonably clean. Little energy needs to be expended to overcome potential energy changes, but a great deal is lost through friction (for cars about 10 kWh per 100 km) and low-efficiency energy conversion. Vehicles can be run either by connecting them to a continuous supply of energy or by storing energy on board. Hydrogen would be ideal as a synthetic fuel because it is lightweight, highly abundant and its oxidation product (water) is environmentally benign, but storage remains a problem. Here we present recent developments in the search for innovative materials with high hydrogen-storage capacity. 18. Inorganic Chemistry in Hydrogen Storage and Biomass Catalysis SciTech Connect Thorn, David 2012-06-13 Making or breaking C-H, B-H, C-C bonds has been at the core of catalysis for many years. Making or breaking these bonds to store or recover energy presents us with fresh challenges, including how to catalyze these transformations in molecular systems that are 'tuned' to minimize energy loss and in molecular and material systems present in biomass. This talk will discuss some challenging transformations in chemical hydrogen storage, and some aspects of the inorganic chemistry we are studying in the development of catalysts for biomass utilization. 19. MODIFIED BOROHYDRIDES FOR REVERSIBLE HYDROGEN STORAGE SciTech Connect Au, Ming 2006-05-10 This paper reports the results in the effort to destabilize lithium borohydride for reversible hydrogen storage. A number of metals, metal hydrides, metal chlorides and complex hydrides were selected and evaluated as the destabilization agents for reducing dehydriding temperature and generating dehydriding-rehydriding reversibility. It is found that some additives are effective. The Raman spectroscopic analysis shows the change of B-H binding nature. 20. Hydrogen Fuel Cells and Storage Technology: Fundamental Research for Optimization of Hydrogen Storage and Utilization SciTech Connect Perret, Bob; Heske, Clemens; Nadavalath, Balakrishnan; Cornelius, Andrew; Hatchett, David; Bae, Chusung; Pang, Tao; Kim, Eunja; Hemmers, Oliver 2011-03-28 Design and development of improved low-cost hydrogen fuel cell catalytic materials and high-capacity hydrogenn storage media are paramount to enabling the hydrogen economy. Presently, effective and durable catalysts are mostly precious metals in pure or alloyed form and their high cost inhibits fuel cell applications. Similarly, materials that meet on-board hydrogen storage targets within total mass and volumetric constraints are yet to be found. Both hydrogen storage performance and cost-effective fuel cell designs are intimately linked to the electronic structure, morphology and cost of the chosen materials. The FCAST Project combined theoretical and experimental studies of electronic structure, chemical bonding, and hydrogen adsorption/desorption characteristics of a number of different nanomaterials and metal clusters to develop better fundamental understanding of hydrogen storage in solid state matrices. Additional experimental studies quantified the hydrogen storage properties of synthesized polyaniline(PANI)/Pd composites. Such conducting polymers are especially interesting because of their high intrinsic electron density and the ability to dope the materials with protons, anions, and metal species. Earlier work produced contradictory results: one study reported 7% to 8% hydrogen uptake while a second study reported zero hydrogen uptake. Cost and durability of fuel cell systems are crucial factors in their affordability. Limits on operating temperature, loss of catalytic reactivity and degradation of proton exchange membranes are factors that affect system durability and contribute to operational costs. More cost effective fuel cell components were sought through studies of the physical and chemical nature of catalyst performance, characterization of oxidation and reduction processes on system surfaces. Additional development effort resulted in a new hydrocarbon-based high-performance sulfonated proton exchange membrane (PEM) that can be manufactured at low 1. A multifaceted approach to hydrogen storage. PubMed Churchard, Andrew J; Banach, Ewa; Borgschulte, Andreas; Caputo, Riccarda; Chen, Jian-Cheng; Clary, David; Fijalkowski, Karol J; Geerlings, Hans; Genova, Radostina V; Grochala, Wojciech; Jaroń, Tomasz; Juanes-Marcos, Juan Carlos; Kasemo, Bengt; Kroes, Geert-Jan; Ljubić, Ivan; Naujoks, Nicola; Nørskov, Jens K; Olsen, Roar A; Pendolino, Flavio; Remhof, Arndt; Románszki, Loránd; Tekin, Adem; Vegge, Tejs; Zäch, Michael; Züttel, Andreas 2011-10-14 The widespread adoption of hydrogen as an energy carrier could bring significant benefits, but only if a number of currently intractable problems can be overcome. Not the least of these is the problem of storage, particularly when aimed at use onboard light-vehicles. The aim of this overview is to look in depth at a number of areas linked by the recently concluded HYDROGEN research network, representing an intentionally multi-faceted selection with the goal of advancing the field on a number of fronts simultaneously. For the general reader we provide a concise outline of the main approaches to storing hydrogen before moving on to detailed reviews of recent research in the solid chemical storage of hydrogen, and so provide an entry point for the interested reader on these diverse topics. The subjects covered include: the mechanisms of Ti catalysis in alanates; the kinetics of the borohydrides and the resulting limitations; novel transition metal catalysts for use with complex hydrides; less common borohydrides; protic-hydridic stores; metal ammines and novel approaches to nano-confined metal hydrides. 2. Coupling of exothermic and endothermic hydrogen storage materials NASA Astrophysics Data System (ADS) Brooks, Kriston P.; Bowden, Mark E.; Karkamkar, Abhijeet J.; Houghton, Adrian Y.; Autrey, S. Thomas 2016-08-01 Chemical hydrogen storage (CHS) materials are a high-storage-density alternative to the gaseous compressed hydrogen currently used to provide hydrogen for fuel cell vehicles. One of the challenges of CHS materials is addressing the energy barriers required to break the chemical bonds and release the hydrogen. Coupling CHS reactions that are endothermic and exothermic during dehydrogenation can improve onboard energy efficiency and thermal control for the system, making such materials viable. Acceptable coupling between reactions requires both thermodynamic and kinetic considerations. In this work, models were developed to predict the reaction enthalpy and rate required to achieve high conversions for both reactions based on experimental measurements. Modeling results show that the coupling efficiency of exothermic and endothermic reactions is more sensitive to the ratio of the exothermic and endothermic enthalpies than to the ratio of the rates of the two steps. Modeling results also show that a slower endothermic step rate is desirable to permit sufficient heating of the reactor by the exothermic step. We look at two examples of a sequential and parallel reaction scheme and provide some of the first published insight into the required temperature range to maximize the hydrogen release from 1,2-BN cyclohexane and indoline. 3. Theoretical Studies of Hydrogen Storage Alloys. SciTech Connect Jonsson, Hannes 2012-03-22 Theoretical calculations were carried out to search for lightweight alloys that can be used to reversibly store hydrogen in mobile applications, such as automobiles. Our primary focus was on magnesium based alloys. While MgH{sub 2} is in many respects a promising hydrogen storage material, there are two serious problems which need to be solved in order to make it useful: (i) the binding energy of the hydrogen atoms in the hydride is too large, causing the release temperature to be too high, and (ii) the diffusion of hydrogen through the hydride is so slow that loading of hydrogen into the metal takes much too long. In the first year of the project, we found that the addition of ca. 15% of aluminum decreases the binding energy to the hydrogen to the target value of 0.25 eV which corresponds to release of 1 bar hydrogen gas at 100 degrees C. Also, the addition of ca. 15% of transition metal atoms, such as Ti or V, reduces the formation energy of interstitial H-atoms making the diffusion of H-atoms through the hydride more than ten orders of magnitude faster at room temperature. In the second year of the project, several calculations of alloys of magnesium with various other transition metals were carried out and systematic trends in stability, hydrogen binding energy and diffusivity established. Some calculations of ternary alloys and their hydrides were also carried out, for example of Mg{sub 6}AlTiH{sub 16}. It was found that the binding energy reduction due to the addition of aluminum and increased diffusivity due to the addition of a transition metal are both effective at the same time. This material would in principle work well for hydrogen storage but it is, unfortunately, unstable with respect to phase separation. A search was made for a ternary alloy of this type where both the alloy and the corresponding hydride are stable. Promising results were obtained by including Zn in the alloy. 4. Efficient hydrogen storage with the combination of lightweight Mg/MgH2 and nanostructures. PubMed Cheng, Fangyi; Tao, Zhanliang; Liang, Jing; Chen, Jun 2012-07-28 Efficient hydrogen storage plays a key role in realizing the incoming hydrogen economy. However, it still remains a great challenge to develop hydrogen storage media with high capacity, favourable thermodynamics, fast kinetics, controllable reversibility, long cycle life, low cost and high safety. To achieve this goal, the combination of lightweight materials and nanostructures should offer great opportunities. In this article, we review recent advances in the field of chemical hydrogen storage that couples lightweight materials and nanostructures, focusing on Mg/MgH(2)-based systems. Selective theoretical and experimental studies on Mg/MgH(2) nanostructures are overviewed, with the emphasis on illustrating the influences of nanostructures on the hydrogenation/dehydrogenation mechanisms and hydrogen storage properties such as capacity, thermodynamics and kinetics. In particular, theoretical studies have shown that the thermodynamics of Mg/MgH(2) clusters below 2 nm change more prominently as particle size decreases. PMID:22715459 5. Microporous Metal Organic Materials for Hydrogen Storage SciTech Connect S. G. Sankar; Jing Li; Karl Johnson 2008-11-30 We have examined a number of Metal Organic Framework Materials for their potential in hydrogen storage applications. Results obtained in this study may, in general, be summarized as follows: (1) We have identified a new family of porous metal organic framework materials with the compositions M (bdc) (ted){sub 0.5}, {l_brace}M = Zn or Co, bdc = biphenyl dicarboxylate and ted = triethylene diamine{r_brace} that adsorb large quantities of hydrogen ({approx}4.6 wt%) at 77 K and a hydrogen pressure of 50 atm. The modeling performed on these materials agree reasonably well with the experimental results. (2) In some instances, such as in Y{sub 2}(sdba){sub 3}, even though the modeling predicted the possibility of hydrogen adsorption (although only small quantities, {approx}1.2 wt%, 77 K, 50 atm. hydrogen), our experiments indicate that the sample does not adsorb any hydrogen. This may be related to the fact that the pores are extremely small or may be attributed to the lack of proper activation process. (3) Some samples such as Zn (tbip) (tbip = 5-tert butyl isophthalate) exhibit hysteresis characteristics in hydrogen sorption between adsorption and desorption runs. Modeling studies on this sample show good agreement with the desorption behavior. It is necessary to conduct additional studies to fully understand this behavior. (4) Molecular simulations have demonstrated the need to enhance the solid-fluid potential of interaction in order to achieve much higher adsorption amounts at room temperature. We speculate that this may be accomplished through incorporation of light transition metals, such as titanium and scandium, into the metal organic framework materials. 6. Carbon nanotube materials for hydrogen storage SciTech Connect Dillon, A.C.; Parilla, P.A.; Jones, K.M.; Riker, G.; Heben, M.J. 1998-08-01 Carbon single-wall nanotubes (SWNTs) are essentially elongated pores of molecular dimensions and are capable of adsorbing hydrogen at relatively high temperatures and low pressures. This behavior is unique to these materials and indicates that SWNTs are the ideal building block for constructing safe, efficient, and high energy density adsorbents for hydrogen storage applications. In past work the authors developed methods for preparing and opening SWNTs, discovered the unique adsorption properties of these new materials, confirmed that hydrogen is stabilized by physical rather than chemical interactions, measured the strength of interaction to be {approximately} 5 times higher than for adsorption on planar graphite, and performed infrared absorption spectroscopy to determine the chemical nature of the surface terminations before, during, and after oxidation. This year the authors have made significant advances in synthesis and characterization of SWNT materials so that they can now prepare gram quantities of high-purity SWNT samples and measure and control the diameter distribution of the tubes by varying key parameters during synthesis. They have also developed methods which purify nanotubes and cut nanotubes into shorter segments. These capabilities provide a means for opening the tubes which were unreactive to the oxidation methods that successfully opened tubes, and offer a path towards organizing nanotube segments to enable high volumetric hydrogen storage densities. They also performed temperature programmed desorption spectroscopy on high purity carbon nanotube material obtained from collaborator Prof. Patrick Bernier and finished construction of a high precision Seiverts apparatus which will allow the hydrogen pressure-temperature-composition phase diagrams to be evaluated for SWNT materials. 7. Hydrogen Fire in a Storage Vessel NASA Technical Reports Server (NTRS) Hester, Zena M. 2010-01-01 On October 23, 2007, the operations team began a procedure to sample the Liquid Hydrogen (LH2) storage vessels ("tanks"), and associated transfer system. This procedure was being performed to determine the conditions within the system, and if necessary, to purge the system of any excess Gaseous Hydrogen (GH2) in preparation for reactivation of the system. The system had not been used since 2003. The LH2 storage system contains two (2) spherical pressure vessels of 225,000 gallons in volume, with a maximum working pressure (MAWP) of 50 psig. Eight inch transfer piping connects them to the usage point. Operations began with activation of the burnstack for the LH2 storage area. Pneumatic (GN2) systems in the storage area were then activated and checked. Pressurization of storage tank number 1 with gaseous nitrogen (GN2) was initiated, with a target pressure of 10 psig, at which point samples were planned to be taken. At 5 psig, a loud noise was heard in the upper area of tank number 2. Smoke was seen exiting the burnstack and from the insulation on vent lines for both tanks. At this time tank number 1 was vented and the pressurization system was secured. The mishap resulted in physical damage to both storage tanks, as well as to some of the piping for both tanks. Corrective action included repair of the damaged hardware by a qualified contractor. Preventive action included documented organizational policy and procedures for establishing standby and mothball conditions for facilities and equipment, including provisions as detailed in the investigation report recommendations: Recommendation 1: The using organization should define necessary activities in order to place hydrogen systems in long term periods of inactivity. The defined activities should address requirements for rendering inert, isolation (i.e., physical disconnect, double block and bleed, etc.) and periodic monitoring. Recommendation 2: The using organization should develop a process to periodically monitor 8. Hydrogen storage in the form of metal hydrides NASA Technical Reports Server (NTRS) Zwanziger, M. G.; Santana, C. C.; Santos, S. C. 1984-01-01 Reversible reactions between hydrogen and such materials as iron/titanium and magnesium/ nickel alloy may provide a means for storing hydrogen fuel. A demonstration model of an iron/titanium hydride storage bed is described. Hydrogen from the hydride storage bed powers a converted gasoline electric generator. 9. Hydrogen from biomass: state of the art and research challenges SciTech Connect Milne, Thomas A; Elam, Carolyn C; Evans, Robert J 2002-02-01 appropriate feedstocks and deployment scenarios that match hydrogen to the local markets. Co-production opportunities are of particular interest for near-term deployment since multiple products improve the economics; however, co-product development is not covered in this report. Biomass has the potential to accelerate the realization of hydrogen as a major fuel of the future. Since biomass is renewable and consumes atmospheric CO2 during growth, it can have a small net CO2 impact compared to fossil fuels. However, hydrogen from biomass has major challenges. There are no completed technology demonstrations. The yield of hydrogen is low from biomass since the hydrogen content in biomass is low to being with (approximately 6% versus 25% for methane) and the energy content is low due to the 40% oxygen content of biomass. Since over half of the hydrogen from biomass comes from splitting water in the steam reforming reaction, the energy content of the feedstock is an inherent limitation of the process . The low yield of hydrogen on a weight basis is misleading since the energy conversion efficiency is high. However, the cost for growing, harvesting, and transporting biomass is high. Thus even with reasonable energy efficiencies, it is not presently economically competitive with natural gas steam reforming for stand-alone hydrogen without the advantage of high-value co-products. Additionally, as with all sources of hydrogen, production from biomass will require appropriate hydrogen storage and utilization systems to be developed and deployed. The report also looked at promising areas for further research and development. The major areas for R,D and D are: feedstock preparation and feeding; gasification gas conditioning; system integration; modular systems development; valuable co-product integration; and larger-scale demonstrations. These are in addition to the challenges for any hydrogen process in storage and utilization technologies. 10. Hydrogen storage in carbon materials—preliminary results NASA Astrophysics Data System (ADS) Jörissen, Ludwig; Klos, Holger; Lamp, Peter; Reichenauer, Gudrun; Trapp, Victor 1998-08-01 Recent developments aiming at the accelerated commercialization of fuel cells for automotive applications have triggered an intensive research on fuel storage concepts for fuel cell cars. The fuel cell technology currently lacks technically and economically viable hydrogen storage technologies. On-board reforming of gasoline or methanol into hydrogen can only be regarded as an intermediate solution due to the inherently poor energy efficiency of such processes. Hydrogen storage in carbon nanofibers may lead to an efficient solution to the above described problems. 11. Hydrogen storage materials and method of making by dry homogenation DOEpatents Jensen, Craig M.; Zidan, Ragaiy A. 2002-01-01 Dry homogenized metal hydrides, in particular aluminum hydride compounds, as a material for reversible hydrogen storage is provided. The reversible hydrogen storage material comprises a dry homogenized material having transition metal catalytic sites on a metal aluminum hydride compound, or mixtures of metal aluminum hydride compounds. A method of making such reversible hydrogen storage materials by dry doping is also provided and comprises the steps of dry homogenizing metal hydrides by mechanical mixing, such as be crushing or ball milling a powder, of a metal aluminum hydride with a transition metal catalyst. In another aspect of the invention, a method of powering a vehicle apparatus with the reversible hydrogen storage material is provided. 12. Chemical hydrogen storage material property guidelines for automotive applications SciTech Connect Semelsberger, Troy; Brooks, Kriston P. 2015-04-01 Chemical hydrogen storage is the sought after hydrogen storage media for automotive applications because of the expected low pressure operation (<20 atm), moderate temperature operation (<200 C), system gravimetric capacities (>0.05 kg H2/kg system), and system volumetric capacities (>0.05 kg H2/L system). Currently, the primary shortcomings of chemical hydrogen storage are regeneration efficiency, fuel cost and fuel phase (i.e., solid or slurry phase). Understanding the required material properties to meet the DOE Technical Targets for Onboard Hydrogen Storage Systems is a critical knowledge gap in the hydrogen storage research community. This study presents a set of fluid-phase chemical hydrogen storage material property guidelines for automotive applications meeting the 2017 DOE technical targets. Viable material properties were determined using a boiler-plate automotive system design. The fluid phase chemical hydrogen storage media considered in this study were neat liquids, solutions, and non-settling homogeneous slurries. Material properties examined include kinetics, heats of reaction, fuel-cell impurities, gravimetric and volumetric hydrogen storage capacities, and regeneration efficiency. The material properties, although not exhaustive, are an essential first step in identifying viable chemical hydrogen storage material propertiesdand most important, their implications on system mass, system volume and system performance. 13. Hydrogen storage in Chabazite zeolite frameworks. PubMed Regli, Laura; Zecchina, Adriano; Vitillo, Jenny G; Cocina, Donato; Spoto, Giuseppe; Lamberti, Carlo; Lillerud, Karl P; Olsbye, Unni; Bordiga, Silvia 2005-09-01 We have recently highlighted that H-SSZ-13, a highly siliceous zeolite (Si/Al = 11.6) with a chabazitic framework, is the most efficient zeolitic material for hydrogen storage [A. Zecchina, S. Bordiga, J. G. Vitillo, G. Ricchiardi, C. Lamberti, G. Spoto, M. Bjørgen and K. P. Lillerud, J. Am. Chem. Soc., 2005, 127, 6361]. The aim of this new study is thus to clarify both the role played by the acidic strength and by the density of the polarizing centers hosted in the same framework topology in the increase of the adsorptive capabilities of the chabazitic materials towards H2. To achieve this goal, the volumetric experiments of H2 uptake (performed at 77 K) and the transmission IR experiment of H2 adsorption at 15 K have been performed on H-SSZ-13, H-SAPO-34 (the isostructural silico-aluminophosphate material with the same Brønsted site density) and H-CHA (the standard chabazite zeolite: Si/Al = 2.1) materials. We have found that a H2 uptake improvement has been obtained by increasing the acidic strength of the Brønsted sites (moving from H-SAPO-34 to H-SSZ-13). Conversely, the important increase of the Brønsted sites density (moving from H-SSZ-13 to H-CHA) has played a negative role. This unexpected behavior has been explained as follows. The additional Brønsted sites are in mutual interaction via H-bonds inside the small cages of the chabazitic framework and for most of them the energetic cost needed to displace the adjacent OH ligand is higher than the adsorption enthalpy of the OH...H2 adduct. From our work it can be concluded that proton exchanged chabazitic frameworks represent, among zeolites, the most efficient materials for hydrogen storage. We have shown that a proper balance between available space (volume accessible to hydrogen), high contact surface, and specific interaction with strong and isolated polarizing centers are the necessary characteristics requested to design better materials for molecular H2 storage. 14. Hydrogen storage in Chabazite zeolite frameworks. PubMed Regli, Laura; Zecchina, Adriano; Vitillo, Jenny G; Cocina, Donato; Spoto, Giuseppe; Lamberti, Carlo; Lillerud, Karl P; Olsbye, Unni; Bordiga, Silvia 2005-09-01 We have recently highlighted that H-SSZ-13, a highly siliceous zeolite (Si/Al = 11.6) with a chabazitic framework, is the most efficient zeolitic material for hydrogen storage [A. Zecchina, S. Bordiga, J. G. Vitillo, G. Ricchiardi, C. Lamberti, G. Spoto, M. Bjørgen and K. P. Lillerud, J. Am. Chem. Soc., 2005, 127, 6361]. The aim of this new study is thus to clarify both the role played by the acidic strength and by the density of the polarizing centers hosted in the same framework topology in the increase of the adsorptive capabilities of the chabazitic materials towards H2. To achieve this goal, the volumetric experiments of H2 uptake (performed at 77 K) and the transmission IR experiment of H2 adsorption at 15 K have been performed on H-SSZ-13, H-SAPO-34 (the isostructural silico-aluminophosphate material with the same Brønsted site density) and H-CHA (the standard chabazite zeolite: Si/Al = 2.1) materials. We have found that a H2 uptake improvement has been obtained by increasing the acidic strength of the Brønsted sites (moving from H-SAPO-34 to H-SSZ-13). Conversely, the important increase of the Brønsted sites density (moving from H-SSZ-13 to H-CHA) has played a negative role. This unexpected behavior has been explained as follows. The additional Brønsted sites are in mutual interaction via H-bonds inside the small cages of the chabazitic framework and for most of them the energetic cost needed to displace the adjacent OH ligand is higher than the adsorption enthalpy of the OH...H2 adduct. From our work it can be concluded that proton exchanged chabazitic frameworks represent, among zeolites, the most efficient materials for hydrogen storage. We have shown that a proper balance between available space (volume accessible to hydrogen), high contact surface, and specific interaction with strong and isolated polarizing centers are the necessary characteristics requested to design better materials for molecular H2 storage. PMID:16240032 15. Hydrogen Peroxide Storage in Small Sealed Tanks SciTech Connect Whitehead, J. 1999-10-20 Unstabilized hydrogen peroxide of 85% concentration has been prepared in laboratory quantities for testing material compatibility and long term storage on a small scale. Vessels made of candidate tank and liner materials ranged in volume from 1 cc to 2540 cc. Numerous metals and plastics were tried at the smallest scales, while promising ones were used to fabricate larger vessels and liners. An aluminum alloy (6061-T6) performed poorly, including increasing homogeneous decay due to alloying elements entering solution. The decay rate in this high strength aluminum was greatly reduced by anodizing. Better results were obtained with polymers, particularly polyvinylidene fluoride. Data reported herein include ullage pressures as a function of time with changing decay rates, and contamination analysis results. 16. Biological hydrogen production: prospects and challenges. PubMed Lee, Hyung-Sool; Vermaas, Wim F J; Rittmann, Bruce E 2010-05-01 Hydrogen gas provides exceptional value as an energy carrier and industrial feedstock, but currently is produced entirely by reforming fossil fuels. Biological hydrogen production (BioH(2)), which offers the possibility of being renewable and carbon neutral, can be achieved by photosynthesis, fermentation, and microbial electrolysis cells. This review introduces the principles, advantages and challenges of each approach to BioH(2). Photosynthetic BioH(2) is the ultimate renewable source, since it directly uses inexhaustible resources: sunlight energy and electrons from H(2)O. However, it presents major technical challenges, particularly due to oxygen sensitivity. Fermentative BioH(2) offers a high production rate, but poor conversion efficiency from the organic substrate to H(2). The microbial electrolysis cell can achieve high conversion efficiency, but is an emerging technology. 17. New perspectives on potential hydrogen storage materials using high pressure. PubMed Song, Yang 2013-09-21 In addressing the global demand for clean and renewable energy, hydrogen stands out as the most suitable candidate for many fuel applications that require practical and efficient storage of hydrogen. Supplementary to the traditional hydrogen storage methods and materials, the high-pressure technique has emerged as a novel and unique approach to developing new potential hydrogen storage materials. Static compression of materials may result in significant changes in the structures, properties and performance that are important for hydrogen storage applications, and often lead to the formation of unprecedented phases or complexes that have profound implications for hydrogen storage. In this perspective article, 22 types of representative potential hydrogen storage materials that belong to four major classes--simple hydride, complex hydride, chemical hydride and hydrogen containing materials--were reviewed. In particular, their structures, stabilities, and pressure-induced transformations, which were reported in recent experimental works together with supporting theoretical studies, were provided. The important contextual aspects pertinent to hydrogen storage associated with novel structures and transitions were discussed. Finally, the summary of the recent advances reviewed and the insight into the future research in this direction were given. 18. Polyaniline-polypyrrole composites with enhanced hydrogen storage capacities. PubMed Attia, Nour F; Geckeler, Kurt E 2013-06-13 A facile method for the synthesis of polyaniline-polypyrrole composite materials with network morphology is developed based on polyaniline nanofibers covered by a thin layer of polypyrrole via vapor phase polymerization. The hydrogen storage capacity of the composites is evaluated at room temperature exhibits a twofold increase in hydrogen storage capacity. The HCl-doped polyaniline nanofibers exhibit a storage capacity of 0.46 wt%, whereas the polyaniline-polypyrrole composites could store 0.91 wt% of hydrogen gas. In addition, the effect of the dopant type, counteranion size, and the doping with palladium nanoparticles on the storage properties are also investigated. 19. Pd doped reduced graphene oxide for hydrogen storage SciTech Connect Das, Tapas; Banerjee, Seemita; Sudarsan, V. 2015-06-24 Pd nanoparticles dispersed reduced graphene oxide sample has been prepared by a simple chemical method using hydrazine as the reducing agent. Based on XRD and {sup 13}C MAS NMR studies it is confirmed that, Pd nanoparticles are effectively mixed with the reduced graphene oxide sample. Maximum hydrogen storage capacity has been estimated to be ∼1.36 wt % at 123K. Improved hydrogen storage capacity of Pd incorporated sample can be explained based on the phenomenon of spillover of atomic hydrogen. 20. Chemisorption On Nanoparticles: An Alternative Mechanism For Hydrogen Storage SciTech Connect Williamson, A; Reboredo, F; Galli, G 2004-04-09 We present first principles, computational predictions of a porous, nano-structured semiconductor material that will reversibly store hydrogen for fuel cell applications. The material is competitive with current metal hydride storage materials, but contains only carbon and silicon, reducing both its cost and environmental impact. Additionally, unlike metal hydrides, the core skeleton structure of this material is unaltered when cycling from full hydrogen storage to full hydrogen depletion, removing engineering complications associated with expansion/contraction of the material. 1. Hydrogen gas storage in fluorinated ultramicroporous tunnel crystal. PubMed Kataoka, Keisuke; Katagiri, Toshimasa 2012-08-21 We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder. PMID:22782245 2. Borazine-boron nitride hybrid hydrogen storage system DOEpatents Narula, Chaitanya K [Knoxville, TN; Simonson, J Michael [Knoxville, TN; Maya, Leon [Knoxville, TN; Paine, Robert T [Albuquerque, NM 2008-04-22 A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride. 3. Electron Charged Graphite-based Hydrogen Storage Material SciTech Connect Dr. Chinbay Q. Fan R&D Manager Office of Technology and Innovations Phone: 847 768 0812 2012-03-14 The electron-charge effects have been demonstrated to enhance hydrogen storage capacity using materials which have inherent hydrogen storage capacities. A charge control agent (CCA) or a charge transfer agent (CTA) was applied to the hydrogen storage material to reduce internal discharge between particles in a Sievert volumetric test device. GTI has tested the device under (1) electrostatic charge mode; (2) ultra-capacitor mode; and (3) metal-hydride mode. GTI has also analyzed the charge distribution on storage materials. The charge control agent and charge transfer agent are needed to prevent internal charge leaks so that the hydrogen atoms can stay on the storage material. GTI has analyzed the hydrogen fueling tank structure, which contains an air or liquid heat exchange framework. The cooling structure is needed for hydrogen fueling/releasing. We found that the cooling structure could be used as electron-charged electrodes, which will exhibit a very uniform charge distribution (because the cooling system needs to remove heat uniformly). Therefore, the electron-charge concept does not have any burden of cost and weight for the hydrogen storage tank system. The energy consumption for the electron-charge enhancement method is quite low or omitted for electrostatic mode and ultra-capacitor mode in comparison of other hydrogen storage methods; however, it could be high for the battery mode. 4. In Pursuit of Sustainable Hydrogen Storage with Boron-Nitride Fullerene as the Storage Medium. PubMed Ganguly, Gaurab; Malakar, Tanmay; Paul, Ankan 2016-06-22 Using well calibrated DFT studies we predict that experimentally synthesized B24 N24 fullerene can serve as a potential reversible chemical hydrogen storage material with hydrogen-gas storage capacity up to 5.13 wt %. Our theoretical studies show that hydrogenation and dehydrogenation of the fullerene framework can be achieved at reasonable rates using existing metal-free hydrogenating agents and base metal-containing dehydrogenation catalysts. PMID:27174725 5. Hydrogen Energy Storage (HES) Activities at NREL; NREL (National Renewable Energy Laboratory) SciTech Connect Eichman, J. 2015-04-21 This presentation provides an overview of hydrogen and energy storage, including hydrogen storage pathways and international power-to-gas activities, and summarizes the National Renewable Energy Laboratory's hydrogen energy storage activities and results. 6. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes - May 2008 SciTech Connect Ott, Kevin C.; Linehan, Sue; Lipiecki, Frank; Christopher, Aardahl L. 2008-05-12 Chemical Hydrogen Storage Center of Excellence FY2008 Second Quarter Milestone Report: Technical report describing assessment of hydrogen storage materials and progress towards meeting DOE’s hydrogen storage targets. 7. Hydrogen Research for Spaceport and Space-Based Applications: Hydrogen Production, Storage, and Transport. Part 3 NASA Technical Reports Server (NTRS) Anderson, Tim; Balaban, Canan 2008-01-01 The activities presented are a broad based approach to advancing key hydrogen related technologies in areas such as fuel cells, hydrogen production, and distributed sensors for hydrogen-leak detection, laser instrumentation for hydrogen-leak detection, and cryogenic transport and storage. Presented are the results from research projects, education and outreach activities, system and trade studies. The work will aid in advancing the state-of-the-art for several critical technologies related to the implementation of a hydrogen infrastructure. Activities conducted are relevant to a number of propulsion and power systems for terrestrial, aeronautics and aerospace applications. Hydrogen storage and in-space hydrogen transport research focused on developing and verifying design concepts for efficient, safe, lightweight liquid hydrogen cryogenic storage systems. Research into hydrogen production had a specific goal of further advancing proton conducting membrane technology in the laboratory at a larger scale. System and process trade studies evaluated the proton conducting membrane technology, specifically, scale-up issues. 8. Hydrogen storage in sodium aluminum hydride. SciTech Connect Ozolins, Vidvuds; Herberg, J.L. (Lawrence Livermore National Laboratories, Livermore, CA); McCarty, Kevin F.; Maxwell, Robert S. (Lawrence Livermore National Laboratories, Livermore, CA); Stumpf, Roland Rudolph; Majzoub, Eric H. 2005-11-01 Sodium aluminum hydride, NaAlH{sub 4}, has been studied for use as a hydrogen storage material. The effect of Ti, as a few mol. % dopant in the system to increase kinetics of hydrogen sorption, is studied with respect to changes in lattice structure of the crystal. No Ti substitution is found in the crystal lattice. Electronic structure calculations indicate that the NaAlH{sub 4} and Na{sub 3}AlH{sub 6} structures are complex-ionic hydrides with Na{sup +} cations and AlH{sub 4}{sup -} and AlH{sub 6}{sup 3-} anions, respectively. Compound formation studies indicate the primary Ti-compound formed when doping the material at 33 at. % is TiAl{sub 3} , and likely Ti-Al compounds at lower doping rates. A general study of sorption kinetics of NaAlH{sub 4}, when doped with a variety of Ti-halide compounds, indicates a uniform response with the kinetics similar for all dopants. NMR multiple quantum studies of solution-doped samples indicate solvent interaction with the doped alanate. Raman spectroscopy was used to study the lattice dynamics of NaAlH{sub 4}, and illustrated the molecular ionic nature of the lattice as a separation of vibrational modes between the AlH{sub 4}{sup -} anion-modes and lattice-modes. In-situ Raman measurements indicate a stable AlH{sub 4}{sup -} anion that is stable at the melting temperature of NaAlH{sub 4}, indicating that Ti-dopants must affect the Al-H bond strength. 9. Thermodynamics and Kinetics of Phase Transformations in Hydrogen Storage Materials SciTech Connect Ceder, Gerbrand; Marzari, Nicola 2011-08-31 The aim of this project is to develop and apply computational materials science tools to determine and predict critical properties of hydrogen storage materials. By better understanding the absorption/desorption mechanisms and characterizing their physical properties it is possible to explore and evaluate new directions for hydrogen storage materials. Particular emphasis is on the determination of the structure and thermodynamics of hydrogen storage materials, the investigation of microscopic mechanisms of hydrogen uptake and release in various materials and the role of catalysts in this process. As a team we have decided to focus on a single material, NaAlH{sub 4}, in order to fully be able to study the many aspects of hydrogen storage. We have focused on phase stability, mass transport and size-dependent reaction mechanisms in this material. 10. Proceedings of the DOE chemical energy storage and hydrogen energy systems contracts review SciTech Connect Not Available 1980-02-01 Sessions were held on electrolysis-based hydrogen storage systems, hydrogen production, hydrogen storage systems, hydrogen storage materials, end-use applications and system studies, chemical heat pump/chemical energy storage systems, systems studies and assessment, thermochemical hydrogen production cycles, advanced production concepts, and containment materials. (LHK) 11. Technical and economic aspects of hydrogen storage in metal hydrides NASA Technical Reports Server (NTRS) Schmitt, R. 1981-01-01 The recovery of hydrogen from such metal hydrides as LiH, MgH2, TiH2, CaH2 and FeTiH compounds is studied, with the aim of evaluating the viability of the technique for the storage of hydrogen fuel. The pressure-temperature dependence of the reactions, enthalpies of formation, the kinetics of the hydrogen absorption and desorption, and the mechanical and chemical stability of the metal hydrides are taken into account in the evaluation. Economic aspects are considered. Development of portable metal hydride hydrogen storage reservoirs is also mentioned. 12. A direct electrochemical route from ilmenite to hydrogen-storage ferrotitanium alloys. PubMed Ma, Meng; Wang, Dihua; Hu, Xiaohong; Jin, Xianbo; Chen, George Z 2006-06-23 An unrecognised but predictable need for a hydrogen-supported society is tens or even hundreds of million tonnes of hydrogen-storage materials, and thus challenges existing technologies in terms of resource and economical realities. Ilmenite is an abundant mineral, and ferrotitanium alloys are among the earliest known hydrogen-storage materials. At present, industrial production of ferrotitanium alloys goes through separate extraction of individual metals, followed by a multistep arc-melting process. In particular, the extraction of titanium from ilmenite is highly energy intensive and tedious, accounting for titanium's high market price and restricted uses. This article reports the electrochemical synthesis of various ferrotitanium alloy powders directly from solid ilmenite in molten calcium chloride. More importantly, it demonstrates, for the first time, that such produced alloy powders can be used without further treatment for hydrogen storage and perform comparably with or better than similar products by means of other methods, but cost just a fraction. 13. Slurry-Based Chemical Hydrogen Storage Systems for Automotive Fuel Cell Applications SciTech Connect Brooks, Kriston P.; Semelsberger, Troy; Simmons, Kevin L.; Van Hassel, Bart A. 2014-05-30 In this paper, the system designs for hydrogen storage using chemical hydrogen materials in an 80 kWe fuel cell, light-duty vehicle are described. Ammonia borane and alane are used for these designs to represent the general classes of exothermic and endothermic materials. The designs are then compared to the USDRIVE/DOE developed set of system level targets for on-board storage. While most of the DOE targets are predicted to be achieved based on the modeling, the system gravimetric and volumetric densities were more challenging and became the focus of this work. The resulting system evaluation determined that the slurry is majority of the system mass. Only modest reductions in the system mass can be expected with improvements in the balance of plant components. Most of the gravimetric improvements will require developing materials with higher inherent storage capacity or by increasing the solids loading of the chemical hydrogen storage material in the slurry. 14. Hydrogen storage capacity of catalytically grown carbon nanofibers. PubMed Rzepka, Matthias; Bauer, Erich; Reichenauer, Gudrun; Schliermann, Thomas; Bernhardt, Babette; Bohmhammel, Klaus; Henneberg, Eva; Knoll, Uta; Maneck, Heinz-Eberhard; Braue, Wolfgang 2005-08-11 In 1996, R. T. K. Baker, and N. M. Rodriguez claimed to have synthesized a new type of carbon nanofiber material capable of storing large amounts of hydrogen at room temperature and pressures above 100 bar, thus making it a powerful candidate for a very efficient energy storage system in mobile applications. Consequently, many scientists all over the world tried to test and verify these findings, however, with partly inconsistent results. We present here for the first time independent hydrogen storage measurements for several types of nanofibers, both synthesized by our group following precisely the specifications given in the literature as well as original samples supplied by Rodriguez and Baker for this study. The hydrogen storage capacities at room temperature and pressures up to 140 bar were quantified independently by gravimetric and volumetric methods, respectively. No significant hydrogen storage capacity has been detected for all carbon nanofibers investigated. 15. Energy storage possibilities of atomic hydrogen NASA Technical Reports Server (NTRS) Etters, R. D.; Dugan, J. V., Jr.; Palmer, R. 1976-01-01 The possibility of storing large amounts of energy in a free radical system such as atomic hydrogen is analyzed. Attention is focused on theoretical calculations of the ground state properties of spin-aligned atomic triplet hydrogen, deuterium, and tritium. The solid-liquid phase transition in atomic hydrogen is also examined. 16. Storage, generation, and use of hydrogen DOEpatents McClaine, Andrew W.; Rolfe, Jonathan L.; Larsen, Christopher A.; Konduri, Ravi K. 2006-05-30 A composition comprising a carrier liquid; a dispersant; and a chemical hydride. The composition can be used in a hydrogen generator to generate hydrogen for use, e.g., as a fuel. A regenerator recovers elemental metal from byproducts of the hydrogen generation process. 17. U.S. Department of Energy Hydrogen Storage Cost Analysis SciTech Connect Law, Karen; Rosenfeld, Jeffrey; Han, Vickie; Chan, Michael; Chiang, Helena; Leonard, Jon 2013-03-11 The overall objective of this project is to conduct cost analyses and estimate costs for on- and off-board hydrogen storage technologies under development by the U.S. Department of Energy (DOE) on a consistent, independent basis. This can help guide DOE and stakeholders toward the most-promising research, development and commercialization pathways for hydrogen-fueled vehicles. A specific focus of the project is to estimate hydrogen storage system cost in high-volume production scenarios relative to the DOE target that was in place when this cost analysis was initiated. This report and its results reflect work conducted by TIAX between 2004 and 2012, including recent refinements and updates. The report provides a system-level evaluation of costs and performance for four broad categories of on-board hydrogen storage: (1) reversible on-board metal hydrides (e.g., magnesium hydride, sodium alanate); (2) regenerable off-board chemical hydrogen storage materials(e.g., hydrolysis of sodium borohydride, ammonia borane); (3) high surface area sorbents (e.g., carbon-based materials); and 4) advanced physical storage (e.g., 700-bar compressed, cryo-compressed and liquid hydrogen). Additionally, the off-board efficiency and processing costs of several hydrogen storage systems were evaluated and reported, including: (1) liquid carrier, (2) sodium borohydride, (3) ammonia borane, and (4) magnesium hydride. TIAX applied a bottom-up costing methodology customized to analyze and quantify the processes used in the manufacture of hydrogen storage systems. This methodology, used in conjunction with ® software and other tools, developed costs for all major tank components, balance-of-tank, tank assembly, and system assembly. Based on this methodology, the figure below shows the projected on-board high-volume factory costs of the various analyzed hydrogen storage systems, as designed. Reductions in the key cost drivers may bring hydrogen storage system costs closer to this DOE target 18. Achieving High Aqueous Energy Storage via Hydrogen-Generation Passivation. PubMed Wang, Yuhang; Cui, Xiaoqi; Zhang, Yueyu; Zhang, Lijuan; Gong, Xingao; Zheng, Gengfeng 2016-09-01 A new design strategy for polyimides/carbon nanotube networks is reported, aiming to passivate the hydrogen-evolution mechanism on the molecular structures of electrodes, thus substantially boosting their aqueous energy-storage capabilities. The intrinsic sluggish hydrogen-evolution activity of polyimides is further passivated via Li(+) association during battery charging, leading to a much wider voltage window and exceptional energy-storage capability. 19. Liquid-phase chemical hydrogen storage: catalytic hydrogen generation under ambient conditions. PubMed Jiang, Hai-Long; Singh, Sanjay Kumar; Yan, Jun-Min; Zhang, Xin-Bo; Xu, Qiang 2010-05-25 There is a demand for a sufficient and sustainable energy supply. Hence, the search for applicable hydrogen storage materials is extremely important owing to the diversified merits of hydrogen energy. Lithium and sodium borohydride, ammonia borane, hydrazine, and formic acid have been extensively investigated as promising hydrogen storage materials based on their relatively high hydrogen content. Significant advances, such as hydrogen generation temperatures and reaction kinetics, have been made in the catalytic hydrolysis of aqueous lithium and sodium borohydride and ammonia borane as well as in the catalytic decomposition of hydrous hydrazine and formic acid. In this Minireview we briefly survey the research progresses in catalytic hydrogen generation from these liquid-phase chemical hydrogen storage materials. 20. DEVELOPMENT OF DOPED NANOPOROUS CARBONS FOR HYDROGEN STORAGE SciTech Connect Lueking, Angela D.; Li, Qixiu; Badding, John V.; Fonseca, Dania; Gutierrez, Humerto; Sakti, Apurba; Adu, Kofi; Schimmel, Michael 2010-03-31 Hydrogen storage materials based on the hydrogen spillover mechanism onto metal-doped nanoporous carbons are studied, in an effort to develop materials that store appreciable hydrogen at ambient temperatures and moderate pressures. We demonstrate that oxidation of the carbon surface can significantly increase the hydrogen uptake of these materials, primarily at low pressure. Trace water present in the system plays a role in the development of active sites, and may further be used as a strategy to increase uptake. Increased surface density of oxygen groups led to a significant enhancement of hydrogen spillover at pressures less than 100 milibar. At 300K, the hydrogen uptake was up to 1.1 wt. % at 100 mbar and increased to 1.4 wt. % at 20 bar. However, only 0.4 wt% of this was desorbable via a pressure reduction at room temperature, and the high lowpressure hydrogen uptake was found only when trace water was present during pretreatment. Although far from DOE hydrogen storage targets, storage at ambient temperature has significant practical advantages oner cryogenic physical adsorbents. The role of trace water in surface modification has significant implications for reproducibility in the field. High-pressure in situ characterization of ideal carbon surfaces in hydrogen suggests re-hybridization is not likely under conditions of practical interest. Advanced characterization is used to probe carbon-hydrogen-metal interactions in a number of systems and new carbon materials have been developed. 1. Solid-State Hydrogen Storage: Storage Capacity,Thermodynamics and Kinetics SciTech Connect Osborn, William; Markmaitree, Tippawan; Shaw, Leonard D.; Ren, Ruiming; Hu, Jian Z.; Kwak, Ja Hun; Yang, Zhenguo 2009-04-01 Solid-state reversible hydrogen storage systems hold great promise for on-board applications. The key criteria for a successful solid-state reversible storage material are high storage capacity, suitable thermodynamic properties, and fast hydriding and dehydriding kinetics. The LiNH2 + LiH system has been utilized as an example system to illustrate these critical issues that are common among other solid-state reversible storage materials. The progress made in thermodynamic destabilization and kinetic enhancements via various approaches have been emphasized. The implications of these advancements in the development of future solid-state reversible hydrogen storage materials are discussed. 2. Thermal management technology for hydrogen storage: Fullerene option SciTech Connect Wang, J.C.; Chen, F.C.; Murphy, R.W. 1996-10-01 Fullerenes are selected as the first option for investigating advanced thermal management technologies for hydrogen storage because of their potentially high volumetric and gravimetric densities. Experimental results indicate that about 6 wt% of hydrogen (corresponding to C{sub 60}H{sub 48}) can be added to and taken out of fullerenes. A model assuming thermally activated hydrogenation and dehydrogenation processes was developed to explain the experimental findings. The activation energies were estimated to be 100 and 160 kJ/mole (1.0 and 1.6 eV/H{sub 2}) for the hydrogenation and dehydrogenation processes, respectively. The difference is interpreted as the heat released during hydrogenation. There are indications that the activation energies and the heat of hydrogenation can be modified by the use of catalysts. Preliminary hydrogen storage simulations for a conceptually simple device were performed. A 1-m long hollow metal cylinder with an inner diameter of 0.02 m was assumed to be filled with fullerene powders. The results indicate that the thermal diffusivity of the fullerenes controls the hydrogenation and dehydrogenation rates. The rates can be significantly modified by changing the thermal diffusivity of the material inside the cylinder, e.g., by incorporating a metal mesh. Results from the simulation suggest that thermal management is essential for efficient hydrogen storage devices using fullerenes. While the preliminary models developed in this study explain some of the observation, more controlled experiments, rigorous model development, and physical property determinations are needed for the development of practical hydrogen storage devices. The use of catalysts to optimize the hydrogen storage characteristics of fullerenes also needs to be pursued. Future cooperative work between Oak Ridge National Laboratory (ORNL) and Material & Electrochemical Research Corporation (MER) is planned to address these needs. 3. Single-catalyst high-weight% hydrogen storage in an N-heterocycle synthesized from lignin hydrogenolysis products and ammonia PubMed Central Forberg, Daniel; Schwob, Tobias; Zaheer, Muhammad; Friedrich, Martin; Miyajima, Nobuyoshi; Kempe, Rhett 2016-01-01 Large-scale energy storage and the utilization of biomass as a sustainable carbon source are global challenges of this century. The reversible storage of hydrogen covalently bound in chemical compounds is a particularly promising energy storage technology. For this, compounds that can be sustainably synthesized and that permit high-weight% hydrogen storage would be highly desirable. Herein, we report that catalytically modified lignin, an indigestible, abundantly available and hitherto barely used biomass, can be harnessed to reversibly store hydrogen. A novel reusable bimetallic catalyst has been developed, which is able to hydrogenate and dehydrogenate N-heterocycles most efficiently. Furthermore, a particular N-heterocycle has been identified that can be synthesized catalytically in one step from the main lignin hydrogenolysis product and ammonia, and in which the new bimetallic catalyst allows multiple cycles of high-weight% hydrogen storage. PMID:27762267 4. Graphene oxide/metal nanocrystal multilaminates as the atomic limit for safe and selective hydrogen storage DOE PAGES Cho, Eun Seon; Ruminski, Anne M.; Aloni, Shaul; Liu, Yi-Sheng; Guo, Jinghua; Urban, Jeffrey J. 2016-02-23 Interest in hydrogen fuel is growing for automotive applications; however, safe, dense, solid-state hydrogen storage remains a formidable scientific challenge. Metal hydrides offer ample storage capacity and do not require cryogens or exceedingly high pressures for operation. However, hydrides have largely been abandoned because of oxidative instability and sluggish kinetics. We report a new, environmentally stable hydrogen storage material constructed of Mg nanocrystals encapsulated by atomically thin and gas-selective reduced graphene oxide (rGO) sheets. This material, protected from oxygen and moisture by the rGO layers, exhibits exceptionally dense hydrogen storage (6.5 wt% and 0.105 kg H2 per litre in themore » total composite). As rGO is atomically thin, this approach minimizes inactive mass in the composite, while also providing a kinetic enhancement to hydrogen sorption performance. In conclusion, these multilaminates of rGO-Mg are able to deliver exceptionally dense hydrogen storage and provide a material platform for harnessing the attributes of sensitive nanomaterials in demanding environments.« less 5. Graphene oxide/metal nanocrystal multilaminates as the atomic limit for safe and selective hydrogen storage PubMed Central Cho, Eun Seon; Ruminski, Anne M.; Aloni, Shaul; Liu, Yi-Sheng; Guo, Jinghua; Urban, Jeffrey J. 2016-01-01 Interest in hydrogen fuel is growing for automotive applications; however, safe, dense, solid-state hydrogen storage remains a formidable scientific challenge. Metal hydrides offer ample storage capacity and do not require cryogens or exceedingly high pressures for operation. However, hydrides have largely been abandoned because of oxidative instability and sluggish kinetics. We report a new, environmentally stable hydrogen storage material constructed of Mg nanocrystals encapsulated by atomically thin and gas-selective reduced graphene oxide (rGO) sheets. This material, protected from oxygen and moisture by the rGO layers, exhibits exceptionally dense hydrogen storage (6.5 wt% and 0.105 kg H2 per litre in the total composite). As rGO is atomically thin, this approach minimizes inactive mass in the composite, while also providing a kinetic enhancement to hydrogen sorption performance. These multilaminates of rGO-Mg are able to deliver exceptionally dense hydrogen storage and provide a material platform for harnessing the attributes of sensitive nanomaterials in demanding environments. PMID:26902901 6. Graphene oxide/metal nanocrystal multilaminates as the atomic limit for safe and selective hydrogen storage. PubMed Cho, Eun Seon; Ruminski, Anne M; Aloni, Shaul; Liu, Yi-Sheng; Guo, Jinghua; Urban, Jeffrey J 2016-02-23 Interest in hydrogen fuel is growing for automotive applications; however, safe, dense, solid-state hydrogen storage remains a formidable scientific challenge. Metal hydrides offer ample storage capacity and do not require cryogens or exceedingly high pressures for operation. However, hydrides have largely been abandoned because of oxidative instability and sluggish kinetics. We report a new, environmentally stable hydrogen storage material constructed of Mg nanocrystals encapsulated by atomically thin and gas-selective reduced graphene oxide (rGO) sheets. This material, protected from oxygen and moisture by the rGO layers, exhibits exceptionally dense hydrogen storage (6.5 wt% and 0.105 kg H2 per litre in the total composite). As rGO is atomically thin, this approach minimizes inactive mass in the composite, while also providing a kinetic enhancement to hydrogen sorption performance. These multilaminates of rGO-Mg are able to deliver exceptionally dense hydrogen storage and provide a material platform for harnessing the attributes of sensitive nanomaterials in demanding environments. 7. Graphene oxide/metal nanocrystal multilaminates as the atomic limit for safe and selective hydrogen storage NASA Astrophysics Data System (ADS) Cho, Eun Seon; Ruminski, Anne M.; Aloni, Shaul; Liu, Yi-Sheng; Guo, Jinghua; Urban, Jeffrey J. 2016-02-01 Interest in hydrogen fuel is growing for automotive applications; however, safe, dense, solid-state hydrogen storage remains a formidable scientific challenge. Metal hydrides offer ample storage capacity and do not require cryogens or exceedingly high pressures for operation. However, hydrides have largely been abandoned because of oxidative instability and sluggish kinetics. We report a new, environmentally stable hydrogen storage material constructed of Mg nanocrystals encapsulated by atomically thin and gas-selective reduced graphene oxide (rGO) sheets. This material, protected from oxygen and moisture by the rGO layers, exhibits exceptionally dense hydrogen storage (6.5 wt% and 0.105 kg H2 per litre in the total composite). As rGO is atomically thin, this approach minimizes inactive mass in the composite, while also providing a kinetic enhancement to hydrogen sorption performance. These multilaminates of rGO-Mg are able to deliver exceptionally dense hydrogen storage and provide a material platform for harnessing the attributes of sensitive nanomaterials in demanding environments. 8. Hydrogen gas storage in fluorinated ultramicroporous tunnel crystal NASA Astrophysics Data System (ADS) Kataoka, Keisuke; Katagiri, Toshimasa 2012-07-01 We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder.We report hydrogen storage at an ordinary pressure due to a bottle-neck effect of an ultramicroporous crystal. Stored hydrogen was kept at an ordinary pressure below -110 °C. The amounts of stored hydrogen gas linearly correlated with the initial pressures. These phenomena suggested the ultramicroporous tunnels worked as a molecular gas cylinder. Electronic supplementary information (ESI) available. CCDC 246922. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c2nr30940h 9. Charge induced enhancement of adsorption for hydrogen storage materials NASA Astrophysics Data System (ADS) Sun, Xiang 2009-12-01 The rising concerns about environmental pollution and global warming have facilitated research interest in hydrogen energy as an alternative energy source. To apply hydrogen for transportations, several issues have to be solved, within which hydrogen storage is the most critical problem. Lots of materials and devices have been developed; however, none is able to meet the DOE storage target. The primary issue for hydrogen physisorption is a weak interaction between hydrogen and the surface of solid materials, resulting negligible adsorption at room temperature. To solve this issue, there is a need to increase the interaction between the hydrogen molecules and adsorbent surface. In this study, intrinsic electric dipole is investigated to enhance the adsorption energy. The results from the computer simulation of single ionic compounds with hydrogen molecules to form hydrogen clusters showed that electrical charge of substances plays an important role in generation of attractive interaction with hydrogen molecules. In order to further examine the effects of static interaction on hydrogen adsorption, activated carbon with a large surface area was impregnated with various ionic salts including LiCl, NaCl, KCl, KBr, and NiCl2 and their performance for hydrogen storage was evaluated by using a volumetric method. Corresponding computer simulations have been carried out by using DFT (Density Functional Theory) method combined with point charge arrays. Both experimental and computational results prove that the adsorption capacity of hydrogen and its interaction with the solid materials increased with electrical dipole moment. Besides the intrinsic dipole, an externally applied electric field could be another means to enhance hydrogen adsorption. Hydrogen adsorption under an applied electric field was examined by using porous nickel foil as electrodes. Electrical signals showed that adsorption capacity increased with the increasing of gas pressure and external electric voltage 10. Use of triphenyl phosphate as risk mitigant for metal amide hydrogen storage materials DOEpatents Cortes-Concepcion, Jose A.; Anton, Donald L. 2016-04-26 A process in a resulting product of the process in which a hydrogen storage metal amide is modified by a ball milling process using an additive of TPP. The resulting product provides for a hydrogen storage metal amide having a coating that renders the hydrogen storage metal amide resistant to air, ambient moisture, and liquid water while improving useful hydrogen storage and release kinetics. 11. A Cassette Based System for Hydrogen Storage and Delivery SciTech Connect Britton Wayne E. 2006-11-29 A hydrogen storage system is described and evaluated. This is based upon a cassette, that is a container for managing hydrogen storage materials. The container is designed to be safe, modular, adaptable to different chemistries, inexpensive, and transportable. A second module receives the cassette and provides the necessary infrastructure to deliver hydrogen from the cassette according to enduser requirements. The modular concept has a number of advantages over approaches that are all in one stand alone systems. The advantages of a cassette based system are discussed, along with results from model and laboratory testing. 12. Overview of geologic storage of natural gas with an emphasis on assessing the feasibility of storing hydrogen. SciTech Connect Lord, Anna Snider 2009-09-01 In many regions across the nation geologic formations are currently being used to store natural gas underground. Storage options are dictated by the regional geology and the operational need. The U.S. Department of Energy (DOE) has an interest in understanding theses various geologic storage options, the advantages and disadvantages, in the hopes of developing an underground facility for the storage of hydrogen as a low cost storage option, as part of the hydrogen delivery infrastructure. Currently, depleted gas/oil reservoirs, aquifers, and salt caverns are the three main types of underground natural gas storage in use today. The other storage options available currently and in the near future, such as abandoned coal mines, lined hard rock caverns, and refrigerated mined caverns, will become more popular as the demand for natural gas storage grows, especially in regions were depleted reservoirs, aquifers, and salt deposits are not available. The storage of hydrogen within the same type of facilities, currently used for natural gas, may add new operational challenges to the existing cavern storage industry, such as the loss of hydrogen through chemical reactions and the occurrence of hydrogen embrittlement. Currently there are only three locations worldwide, two of which are in the United States, which store hydrogen. All three sites store hydrogen within salt caverns. 13. Enhanced hydrogen storage by using lithium decoration on phosphorene NASA Astrophysics Data System (ADS) Yu, Zhiyuan; Wan, Neng; Lei, Shuangying; Yu, Hong 2016-07-01 The hydrogen storage characteristics of Li decorated phosphorene were systematically investigated based on first-principle density functional theory. It is revealed that the adsorption of H2 on pristine phosphorene is relatively weak with an adsorption energy of 0.06 eV. While this value can be dramatically enhanced to ˜0.2 eV after the phosphorene was decorated by Li, and each Li atom can adsorb up to three H2 molecules. The detailed mechanism of the enhanced hydrogen storage was discussed based on our density functional theory calculations. Our studies give a conservative prediction of hydrogen storage capacity to be 4.4 wt. % through Li decoration on pristine phosphorene. By comparing our calculations to the present molecular dynamic simulation results, we expect our adsorption system is stable under room temperature and hydrogen can be released after moderate heating. 14. A single-component liquid-phase hydrogen storage material. PubMed Luo, Wei; Campbell, Patrick G; Zakharov, Lev N; Liu, Shih-Yuan 2011-12-01 The current state-of-the-art for hydrogen storage is compressed H(2) at 700 bar. The development of a liquid-phase hydrogen storage material has the potential to take advantage of the existing liquid-based distribution infrastructure. We describe a liquid-phase hydrogen storage material that is a liquid under ambient conditions (i.e., at 20 °C and 1 atm pressure), air- and moisture-stable, and recyclable; releases H(2) controllably and cleanly at temperatures below or at the proton exchange membrane fuel cell waste-heat temperature of 80 °C; utilizes catalysts that are cheap and abundant for H(2) desorption; features reasonable gravimetric and volumetric storage capacity; and does not undergo a phase change upon H(2) desorption. 15. Metal-inorganic-organic matrices as efficient sorbents for hydrogen storage. PubMed Azzouz, Abdelkrim; Nousir, Saadia; Bouazizi, Nabil; Roy, René 2015-03-01 Stabilization of metal nanoparticles (MNPs) without re-aggregation is a major challenge. An unprecedented strategy is developed for achieving high dispersion of copper(0) or palladium(0) on montmorillonite-supported diethanolamine or thioglycerol. This results in novel metal-inorganic-organic matrices (MIOM) that readily capture hydrogen at ambient conditions, with easy release under air stream. Hydrogen retention appears to involve mainly physical interactions, slightly stronger on thioglycerol-based MIOM (S-MIOM). Thermal enhancement of desorption suggests also a contribution of chemical interactions. The increase of hydrogen uptake with prolonged contact times arises from diffusion hindrance, which appears to be beneficial by favoring hydrogen entrapment. Even with compact structures, MIOMs act as efficient sorbents with much higher efficiency factor (1.14-1.17 mmol H 2 m(-2)) than many other sophisticated adsorbents reported in the literature. This opens new prospects for hydrogen storage and potential applications in microfluidic hydrogenation reactions. 16. Integrating hydrogen generation and storage in a novel compact electrochemical system based on metal hydrides NASA Astrophysics Data System (ADS) Rangel, C. M.; Fernandes, V. R.; Slavkov, Y.; Bozukov, L. The development of efficient and reliable energy storage systems based on hydrogen technology represents a challenge to seasonal storage based on renewable hydrogen. State of the art renewable energy generation systems include separate units such as electrolyzer, hydrogen storage vessel and a fuel cell system for the conversion of H 2 back into electricity, when required. In this work, a novel electrochemical system has been developed which integrates hydrogen production, storage and compression in only one device, at relatively low cost and high efficiency. The developed prototype comprises a six-electrode cell assembly using an AB 5-type metal hydride and Ni plates as counter electrodes, in a 35-wt% KOH solution. Metal hydride electrodes with chemical composition LaNi 4.3Co 0.4Al 0.3 were prepared by high frequency vacuum melting followed by high temperature annealing. X-ray phase analysis showed typical hexagonal structure and no traces of other intermetallic compounds belonging to the La-Ni phase diagram. Thermodynamic study has been performed in a Sieverts type of apparatus produced by Labtech Int. During cycling, the charging/discharging process was studied in situ using a gas chromatograph from Agilent. It is anticipated that the device will be integrated as a combined hydrogen generator and storage unit in a stand-alone system associated to a 1-kW fuel cell. 17. FINAL REPORT: Room Temperature Hydrogen Storage in Nano-Confined Liquids SciTech Connect VAJO, JOHN 2014-06-12 DOE continues to seek solid-state hydrogen storage materials with hydrogen densities of ≥6 wt% and ≥50 g/L that can deliver hydrogen and be recharged at room temperature and moderate pressures enabling widespread use in transportation applications. Meanwhile, development including vehicle engineering and delivery infrastructure continues for compressed-gas hydrogen storage systems. Although compressed gas storage avoids the materials-based issues associated with solid-state storage, achieving acceptable volumetric densities has been a persistent challenge. This project examined the possibility of developing storage materials that would be compatible with compressed gas storage technology based on enhanced hydrogen solubility in nano-confined liquid solvents. These materials would store hydrogen in molecular form eliminating many limitations of current solid-state materials while increasing the volumetric capacity of compressed hydrogen storage vessels. Experimental methods were developed to study hydrogen solubility in nano-confined liquids. These methods included 1) fabrication of composites comprised of volatile liquid solvents for hydrogen confined within the nano-sized pore volume of nanoporous scaffolds and 2) measuring the hydrogen uptake capacity of these composites without altering the composite composition. The hydrogen storage capacities of these nano-confined solvent/scaffold composites were compared with bulk solvents and with empty scaffolds. The solvents and scaffolds were varied to optimize the enhancement in hydrogen solubility that accompanies confinement of the solvent. In addition, computational simulations were performed to study the molecular-scale structure of liquid solvent when confined within an atomically realistic nano-sized pore of a model scaffold. Confined solvent was compared with similar simulations of bulk solvent. The results from the simulations were used to formulate a mechanism for the enhanced solubility and to guide the 18. Hydrogen storage in insulated pressure vessels SciTech Connect Aceves, S.M.; Garcia-Villazana, O. 1998-08-01 Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH{sub 2}) or ambient-temperature compressed hydrogen (CH{sub 2}). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current analysis and experimental plans for testing insulated pressure vessels. The results show significant advantages to the use of insulated pressure vessels for light-duty vehicles. 19. Direct Evidence for Solid-like Hydrogen in a Nanoporous Carbon Hydrogen Storage Material at Supercritical Temperatures. PubMed Ting, Valeska P; Ramirez-Cuesta, Anibal J; Bimbo, Nuno; Sharpe, Jessica E; Noguera-Diaz, Antonio; Presser, Volker; Rudic, Svemir; Mays, Timothy J 2015-08-25 Here we report direct physical evidence that confinement of molecular hydrogen (H2) in an optimized nanoporous carbon results in accumulation of hydrogen with characteristics commensurate with solid H2 at temperatures up to 67 K above the liquid-vapor critical temperature of bulk H2. This extreme densification is attributed to confinement of H2 molecules in the optimally sized micropores, and occurs at pressures as low as 0.02 MPa. The quantities of contained, solid-like H2 increased with pressure and were directly evaluated using in situ inelastic neutron scattering and confirmed by analysis of gas sorption isotherms. The demonstration of the existence of solid-like H2 challenges the existing assumption that supercritical hydrogen confined in nanopores has an upper limit of liquid H2 density. Thus, this insight offers opportunities for the development of more accurate models for the evaluation and design of nanoporous materials for high capacity adsorptive hydrogen storage. 20. Metal-functionalized silicene for efficient hydrogen storage. PubMed Hussain, Tanveer; Chakraborty, Sudip; Ahuja, Rajeev 2013-10-21 First-principles calculations based on density functional theory are used to investigate the electronic structure along with the stability, bonding mechanism, band gap, and charge transfer of metal-functionalized silicene to envisage its hydrogen-storage capacity. Various metal atoms including Li, Na, K, Be, Mg, and Ca are doped into the most stable configuration of silicene. The corresponding binding energies and charge-transfer mechanisms are discussed from the perspective of hydrogen-storage compatibility. The Li and Na metal dopants are found to be ideally suitable, not only for strong metal-to-substrate binding and uniform distribution over the substrate, but also for the high-capacity storage of hydrogen. The stabilities of both Li- and Na-functionalized silicene are also confirmed through molecular dynamics simulations. It is found that both of the alkali metals, Li(+) and Na(+), can adsorb five hydrogen molecules, attaining reasonably high storage capacities of 7.75 and 6.9 wt %, respectively, with average adsorption energies within the range suitable for practical hydrogen-storage applications. 1. Activatino of Erbium Films for Hydrogen Storage SciTech Connect M Brumbach; j Ohlhausen; K Zavadil; C Snow; J Woicik 2011-12-31 Hydriding of metals can be routinely performed at high temperature in a rich hydrogen atmosphere. Prior to the hydrogen loading process, a thermal activation procedure is required to promote facile hydrogen sorption into the metal. Despite the wide spread utilization of this activation procedure, little is known about the chemical and electronic changes that occur during activation and how this thermal pretreatment leads to increased rates of hydrogen uptake. This study utilized variable kinetic energy X-ray photoelectron spectroscopy to interrogate the changes during in situ thermal annealing of erbium films, with results confirmed by time-of-flight secondary ion mass spectrometry and low energy ion scattering. Activation can be identified by a large increase in photoemission between the valence band edge and the Fermi level and appears to occur over a two stage process. The first stage involves desorption of contaminants and recrystallization of the oxide, initially impeding hydrogen loading. Further heating overcomes the first stage and leads to degradation of the passive surface oxide leading to a bulk film more accessible for hydrogen loading. 2. Activation of erbium films for hydrogen storage NASA Astrophysics Data System (ADS) Brumbach, Michael T.; Ohlhausen, James A.; Zavadil, Kevin R.; Snow, Clark S.; Woicik, Joseph C. 2011-06-01 Hydriding of metals can be routinely performed at high temperature in a rich hydrogen atmosphere. Prior to the hydrogen loading process, a thermal activation procedure is required to promote facile hydrogen sorption into the metal. Despite the wide spread utilization of this activation procedure, little is known about the chemical and electronic changes that occur during activation and how this thermal pretreatment leads to increased rates of hydrogen uptake. This study utilized variable kinetic energy X-ray photoelectron spectroscopy to interrogate the changes during in situ thermal annealing of erbium films, with results confirmed by time-of-flight secondary ion mass spectrometry and low energy ion scattering. Activation can be identified by a large increase in photoemission between the valence band edge and the Fermi level and appears to occur over a two stage process. The first stage involves desorption of contaminants and recrystallization of the oxide, initially impeding hydrogen loading. Further heating overcomes the first stage and leads to degradation of the passive surface oxide leading to a bulk film more accessible for hydrogen loading. 3. Anisotropic storage medium development in a full-scale, sodium alanate-based, hydrogen storage system DOE PAGES Jorgensen, Scott W.; Johnson, Terry A.; Payzant, E. Andrew; Bilheux, Hassina Z. 2016-06-11 Deuterium desorption in an automotive-scale hydrogen storage tube was studied in-situ using neutron diffraction. Gradients in the concentration of the various alanate phases were observed along the length of the tube but no significant radial anisotropy was present. In addition, neutron radiography and computed tomography showed large scale cracks and density fluctuations, confirming the presence of these structures in an undisturbed storage system. These results demonstrate that large scale storage structures are not uniform even after many absorption/desorption cycles and that movement of gaseous hydrogen cannot be properly modeled by a simple porous bed model. In addition, the evidence indicatesmore » that there is slow transformation of species at one end of the tube indicating loss of catalyst functionality. These observations explain the unusually fast movement of hydrogen in a full scale system and shows that loss of capacity is not occurring uniformly in this type of hydrogen-storage system.« less 4. Recommended Best Practices for the Characterization of Storage Properties of Hydrogen Storage Materials SciTech Connect 2010-03-01 This is a reference guide to common methodologies and protocols for measuring critical performance properties of advanced hydrogen storage materials. It helps users to communicate clearly the relevant performance properties of new materials as they are discovered and tested. 5. Theoretical maximal storage of hydrogen in zeolitic frameworks. PubMed Vitillo, Jenny G; Ricchiardi, Gabriele; Spoto, Giuseppe; Zecchina, Adriano 2005-12-01 Physisorption and encapsulation of molecular hydrogen in tailored microporous materials are two of the options for hydrogen storage. Among these materials, zeolites have been widely investigated. In these materials, the attained storage capacities vary widely with structure and composition, leading to the expectation that materials with improved binding sites, together with lighter frameworks, may represent efficient storage materials. In this work, we address the problem of the determination of the maximum amount of molecular hydrogen which could, in principle, be stored in a given zeolitic framework, as limited by the size, structure and flexibility of its pore system. To this end, the progressive filling with H2 of 12 purely siliceous models of common zeolite frameworks has been simulated by means of classical molecular mechanics. By monitoring the variation of cell parameters upon progressive filling of the pores, conclusions are drawn regarding the maximum storage capacity of each framework and, more generally, on framework flexibility. The flexible non-pentasils RHO, FAU, KFI, LTA and CHA display the highest maximal capacities, ranging between 2.86-2.65 mass%, well below the targets set for automotive applications but still in an interesting range. The predicted maximal storage capacities correlate well with experimental results obtained at low temperature. The technique is easily extendable to any other microporous structure, and it can provide a method for the screening of hypothetical new materials for hydrogen storage applications. 6. LANL Virtual Center for Chemical Hydrogen Storage: Chemical Hydrogen Storage Using Ultra-high Surface Area Main Group Materials SciTech Connect Susan M. Kauzlarich; Phillip P. Power; Doinita Neiner; Alex Pickering; Eric Rivard; Bobby Ellis, T. M.; Atkins, A. Merrill; R. Wolf; Julia Wang 2010-09-05 The focus of the project was to design and synthesize light element compounds and nanomaterials that will reversibly store molecular hydrogen for hydrogen storage materials. The primary targets investigated during the last year were amine and hydrogen terminated silicon (Si) nanoparticles, Si alloyed with lighter elements (carbon (C) and boron (B)) and boron nanoparticles. The large surface area of nanoparticles should facilitate a favorable weight to volume ratio, while the low molecular weight elements such as B, nitrogen (N), and Si exist in a variety of inexpensive and readily available precursors. Furthermore, small NPs of Si are nontoxic and non-corrosive. Insights gained from these studies will be applied toward the design and synthesis of hydrogen storage materials that meet the DOE 2010 hydrogen storage targets: cost, hydrogen capacity and reversibility. Two primary routes were explored for the production of nanoparticles smaller than 10 nm in diameter. The first was the reduction of the elemental halides to achieve nanomaterials with chloride surface termination that could subsequently be replaced with amine or hydrogen. The second was the reaction of alkali metal Si or Si alloys with ammonium halides to produce hydrogen capped nanomaterials. These materials were characterized via X-ray powder diffraction, TEM, FTIR, TG/DSC, and NMR spectroscopy. 7. 14 CFR 420.66 - Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen... Code of Federal Regulations, 2013 CFR 2013-01-01 ... storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored... Responsibilities of a Licensee § 420.66 Separation distance requirements for storage of hydrogen peroxide... section for each explosive hazard facility storing: (1) Hydrogen peroxide in concentrations of... 8. 14 CFR 420.66 - Separation distance requirements for storage of hydrogen peroxide, hydrazine, and liquid hydrogen... Code of Federal Regulations, 2014 CFR 2014-01-01 ... storage of hydrogen peroxide, hydrazine, and liquid hydrogen and any incompatible energetic liquids stored... Responsibilities of a Licensee § 420.66 Separation distance requirements for storage of hydrogen peroxide... section for each explosive hazard facility storing: (1) Hydrogen peroxide in concentrations of... 9. Evaluation of insulated pressure vessels for cryogenic hydrogen storage SciTech Connect Aceves, S M; Garcia-Villazana, O; Martinez-Frias, J 1999-03-01 This paper presents an analytical and experimental evaluation of the applicability of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LH?) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). The purpose of this work is to verify that commercially available aluminum-lined, fiber- wrapped vessels can be used for cryogenic hydrogen storage. The paper reports on previous and ongoing tests and analyses that have the purpose of improving the system design and assure its safety. 10. Synthesis, characterization and hydrogen storage studies on porous carbon SciTech Connect Ruz, Priyanka Banerjee, Seemita; Sudarsan, V.; Pandey, M. 2015-06-24 Porous carbon sample has been prepared, using zeolite-Y as template followed by annealing at 800°C, with view to estimate the extent of hydrogen storage by the sample. Based on XRD, {sup 13}C MAS NMR and Raman spectroscopic studies it is confirmed that the porous Carbon sample contains only sp{sup 2} hybridized carbon. The hydrogen sorption isotherms have been recorded for the sample at 273, 223K and 123K and the maximum hydrogen absorption capacity is found to be 1.47wt% at 123K. The interaction energy of hydrogen with the carbon framework was determined to be ∼ 10 kJ mol{sup −1}at lower hydrogen uptake and gradually decreases with increase in hydrogen loading. 11. Lunar-derived titanium alloys for hydrogen storage NASA Technical Reports Server (NTRS) Love, S.; Hertzberg, A.; Woodcock, G. 1992-01-01 Hydrogen gas, which plays an important role in many projected lunar power systems and industrial processes, can be stored in metallic titanium and in certain titanium alloys as an interstitial hydride compound. Storing and retrieving hydrogen with titanium-iron alloy requires substantially less energy investment than storage by liquefaction. Metal hydride storage systems can be designed to operate at a wide range of temperatures and pressures. A few such systems have been developed for terrestrial applications. A drawback of metal hydride storage for lunar applications is the system's large mass per mole of hydrogen stored, which rules out transporting it from earth. The transportation problem can be solved by using native lunar materials, which are rich in titanium and iron. 12. Energy storage possibilities of atomic hydrogen NASA Technical Reports Server (NTRS) Etters, R. D.; Dugan, J. V., Jr.; Palmer, R. 1976-01-01 Several recent experiments designed to produce and store macroscopic quantities of atomic hydrogen are discussed. The bulk, ground state properties of atomic hydrogen, deuterium, and tritium systems are calculated assuming that all pair interactions occur via the atomic triplet potential. The conditions required to obtain this system, including inhibition of recombination through the energetically favorable singlet interaction, are discussed. The internal energy, pressure, and compressibility are calculated applying the Monte Carlo technique with a quantum mechanical variational wavefunction. The system studied consisted of 32 atoms in a box with periodic boundary conditions. Results show that atomic triplet hydrogen and deuterium remain gaseous at 0 K; i.e., the internal energy is positive at all molar volumes considered. 13. Thermodynamically Tuned Nanophase Materials for reversible Hydrogen storage SciTech Connect Ping Liu; John J. Vajo 2010-02-28 This program was devoted to significantly extending the limits of hydrogen storage technology for practical transportation applications. To meet the hydrogen capacity goals set forth by the DOE, solid-state materials consisting of light elements were developed. Many light element compounds are known that have high capacities. However, most of these materials are thermodynamically too stable, and they release and store hydrogen much too slowly for practical use. In this project we developed new light element chemical systems that have high hydrogen capacities while also having suitable thermodynamic properties. In addition, we developed methods for increasing the rates of hydrogen exchange in these new materials. The program has significantly advanced (1) the application of combined hydride systems for tuning thermodynamic properties and (2) the use of nanoengineering for improving hydrogen exchange. For example, we found that our strategy for thermodynamic tuning allows both entropy and enthalpy to be favorably adjusted. In addition, we demonstrated that using porous supports as scaffolds to confine hydride materials to nanoscale dimensions could improve rates of hydrogen exchange by > 50x. Although a hydrogen storage material meeting the requirements for commercial development was not achieved, this program has provided foundation and direction for future efforts. More broadly, nanoconfinment using scaffolds has application in other energy storage technologies including batteries and supercapacitors. The overall goal of this program was to develop a safe and cost-effective nanostructured light-element hydride material that overcomes the thermodynamic and kinetic barriers to hydrogen reaction and diffusion in current materials and thereby achieve > 6 weight percent hydrogen capacity at temperatures and equilibrium pressures consistent with DOE target values. 14. The development of a fullerene based hydrogen storage system SciTech Connect Brosha, E.L.; Davey, J.R.; Garzon, F.H.; Gottesfeld, S. 1998-11-01 This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project objective was to evaluate hydrogen uptake by fullerene substrates and to probe the potential of the hydrogen/fullerene system for hydrogen fuel storage. As part of this project, the authors have completed and tested a fully automated, computer controlled system for measuring hydrogen uptake that is capable of handling both a vacuum of 1 x 10{sup -6} torr and pressures greater than 200 bars. The authors have first established conditions for significant uptake of hydrogen by fullerenes. Subsequently, hydrogenation and dehydrogenation of pure and catalyst-doped C60 was further studied to probe suitability for hydrogen storage applications. C60 {center_dot} H18.7 was prepared at 100 bar H2 and 400 C, corresponding to hydrogen uptake of 2.6 wt%. Dehydrogenation of C60 {center_dot} H18.7 was studied using thermogravimetric and powder x-ray diffraction analysis. The C60 {center_dot} H18.7 molecule was found to be stable up to 430 C in Ar, at which point the release of hydrogen took place simultaneously with the collapse of the fullerene structure. X-ray diffraction analysis performed on C60 {center_dot} H18.7 samples dehydrogenated at 454 C, 475 C, and 600 C showed an increasing volume fraction of amorphous material due to randomly oriented, single-layer graphine sheets. Evolved gas analysis using gas chromatography and mass spectroscopy confirmed the presence of both H{sub 2} and methane upon dehydrogenation, indicating decomposition of the fullerene. The remaining carbon could not be re-hydrogenated. These results provide the first complete evidence for the irreversible nature of fullerene hydrogenation and for limitations imposed on the hydrogenation/dehydrogenation cycle by the limited thermal stability of the molecular crystal of fullerene. 15. Hydrogen Storage in Carbon Nanotubes at High Pressures LDRD Final Report 03-ERD-047 SciTech Connect Evans, W J; Cynn, H 2004-02-16 This goal of this project was to perform feasibility experiments and measurements of the fundamental interactions between hydrogen and single wall carbon nanotubes (SWNT) at high pressures. High-pressure is an adjustable experimental parameter for tuning interaction strengths, thereby elucidating and providing insights into the fundamental nature of the H{sub 2}/SWNT system. We have developed and utilized systems and methodologies to make x-ray scattering, optical spectroscopic and electrical transport measurements. These activities have been productive in demonstrating capabilities and measuring properties of SWNTs under high-pressure conditions. We have also developed strong cooperative and complementary relationships with academic research colleagues at Stanford University. Building on these results and relationships, we hope to continue and expand our research as co-investigators in a joint Harvard-LLNL-Stanford proposal to the DOE ''Grand Challenge'' for Basic and Applied Research in Hydrogen Storage (Solicitation No. DE-PS36-03GO93013). Hydrogen storage is an active research topic with important basic science implications and a crucial enabling technology for advanced energy systems. Measurements of the H{sub 2} storage capacity indicate that it may achieve or exceed the storage capacity level (6.5 wt-%) mandated by the DOE hydrogen plan for fielding a hydrogen-fueled vehicle. The H{sub 2}/SWNT system has been the subject of intensive study and controversy regarding this storage capacity, with various conflicting measurements ranging from 1 wt-% up to values exceeding 7 wt-%[1-5]. The mechanism and details of the hydrogen storage in SWNT systems is poorly understood and several key questions have not been definitively determined including: (1) importance of SWNT structural parameters (tube length, diameter, end termination, bundling); (2) adsorption sites, mechanism, and binding energy; and (3) optimal storage capacity and conditions. This project sought to 16. Hydrogen-air energy storage gas-turbine system NASA Astrophysics Data System (ADS) Schastlivtsev, A. I.; Nazarova, O. V. 2016-02-01 A hydrogen-air energy storage gas-turbine unit is considered that can be used in both nuclear and centralized power industries. However, it is the most promising when used for power-generating plants based on renewable energy sources (RES). The basic feature of the energy storage system in question is combination of storing the energy in compressed air and hydrogen and oxygen produced by the water electrolysis. Such a process makes the energy storage more flexible, in particular, when applied to RES-based power-generating plants whose generation of power may considerably vary during the course of a day, and also reduces the specific cost of the system by decreasing the required volume of the reservoir. This will allow construction of such systems in any areas independent of the local topography in contrast to the compressed-air energy storage gas-turbine plants, which require large-sized underground reservoirs. It should be noted that, during the energy recovery, the air that arrives from the reservoir is heated by combustion of hydrogen in oxygen, which results in the gas-turbine exhaust gases practically free of substances hazardous to the health and the environment. The results of analysis of a hydrogen-air energy storage gas-turbine system are presented. Its layout and the principle of its operation are described and the basic parameters are computed. The units of the system are analyzed and their costs are assessed; the recovery factor is estimated at more than 60%. According to the obtained results, almost all main components of the hydrogen-air energy storage gas-turbine system are well known at present; therefore, no considerable R&D costs are required. A new component of the system is the H2-O2 combustion chamber; a difficulty in manufacturing it is the necessity of ensuring the combustion of hydrogen in oxygen as complete as possible and preventing formation of nitric oxides. 17. HYDROGEN CONCENTRATIONS DURING STORAGE OF 3013 OXIDE SAMPLES SciTech Connect Hensel, S.; Askew, N.; Laurinat, J. 2011-03-14 As part of a surveillance program intended to ensure the safe storage of plutonium bearing nuclear materials in the Savannah River Site (SRS) K-Area Materials Storage (KAMS), samples of these materials are shipped to Savannah River National Laboratory (SRNL) for analysis. These samples are in the form of solids or powders which will have absorbed moisture. Potentially flammable hydrogen gas is generated due to radiolysis of the moisture. The samples are shipped for processing after chemical analysis. To preclude the possibility of a hydrogen deflagration or detonation inside the shipping containers, the shipping times are limited to ensure that hydrogen concentration in the vapor space of every layer of confinement is below the lower flammability limit of 4 volume percent (vol%). This study presents an analysis of the rate of hydrogen accumulation due to radiolysis and calculation of allowable shipping times for typical KAMS materials. 18. Hydrogen Absorption in Fluids: An Unexplored Solution for Onboard Hydrogen Storage SciTech Connect Berry, G D 2005-02-10 Adoption of hydrogen (H{sub 2}) vehicles has been advocated for decades as an ecological ideal, capable of eliminating petroleum consumption as well as tail-pipe air pollution and carbon dioxide (CO{sub 2}) from automobiles. Storing sufficient hydrogen fuel onboard still remains a great technological challenge, despite recent advances in lightweight automotive materials, hybrid-electric drivetrains and fuel cells enabling 60-100 mpg equivalent H{sub 2}-fueled automobiles. Future onboard hydrogen storage choices will be pivotal, with lasting strategic consequences for the eventual scale, shape, security, investment requirements, and energy intensity of the H{sub 2} refueling infrastructure, in addition to impacts on automotive design, cost, range, performance, and safety. Multiple hydrogen storage approaches have been examined and deployed onboard prototype automobiles since the 1970's. These include storing H{sub 2} as a cryogenic liquid (LH{sub 2}) at temperatures of 20-25 Kelvin, compressing room temperature H{sub 2} gas to pressures as high as 10,000 psi, and reversible chemical absorption storage within powdered metal hydrides (e.g. LaNi{sub 5}H{sub 6}, TiFeH{sub 2}, MgH{sub 2}, NaAlH{sub 4}) which evolve H{sub 2} when warmed. Each of these approaches face well-known fundamental physical limits (thermal endurance, volume, and weight, respectively). This report details preliminary experiments investigating the potential of a new approach to H{sub 2} storage: absorption in fluids, specifically liquid nitrogen (LN{sub 2}). N{sub 2} was chosen for this study because it offers unique advantages as an inert but lightweight solvent with high hydrogen solubility and is an abundant atmospheric component. H{sub 2} absorbed in liquid nitrogen (LN{sub 2}) can be lighter than metal hydrides, with greater thermal endurance than cryogenic H{sub 2} or LH{sub 2}, while being more compact than ambient compressed H{sub 2}. Previous researchers have examined H{sub 2} mixed with a 19. Direct Hydrogenation Magnesium Boride to Magnesium Borohydride: Demonstration of >11 Weight Percent Reversible Hydrogen Storage SciTech Connect Severa, Godwin; Ronnebro, Ewa; Jensen, Craig M. 2010-11-16 We here for the first time demonstrate direct hydrogenation of magnesium boride, MgB2, to magnesium borohydride, Mg(BH4)2 at 900 bar H2-pressures and 400°C. Upon 14.8wt% hydrogen release, the end-decomposition product of Mg(BH4)2 is MgB2, thus, this is a unique reversible path here obtaining >11wt% H2 which implies promise for a fully reversible hydrogen storage material. 20. Iron-titanium-mischmetal alloys for hydrogen storage DOEpatents Sandrock, Gary Dale 1978-01-01 A method for the preparation of an iron-titanium-mischmetal alloy which is used for the storage of hydrogen. The alloy is prepared by air-melting an iron charge in a clay-graphite crucible, adding titanium and deoxidizing with mischmetal. The resultant alloy contains less than about 0.1% oxygen and exhibits a capability for hydrogen sorption in less than half the time required by vacuum-melted, iron-titanium alloys. 1. Hydrogen storage in Earth's mantle and core NASA Technical Reports Server (NTRS) Prewitt, Charles T. 1994-01-01 Two different approaches to explaining how hydrogen might be stored in the mantle are illustrated by a number of papers published over the past 25-30 years, but there has been little attempt to provide objective comparisons of the two. One approach invokes the presence in the mantle of dense hydrous magnesium silicates (DHMS) stable at elevated pressures and temperatures. The other involves nominally anhydrous minerals (NAM) that contain hydrogen as a minor constituent on the ppm level. Experimental studies on DHMS indicate these phases may be stable to pressures and temperatures as high at 16 GPa and 1200 C. This temperature is lower than that indicated by a mantle geotherm at 16 GPa, but may be reasonable for a subducting slab. It is possible that other DHMS could be stable to even higher pressures, but little is known about maximum temperature limits. For NAM, small amounts of hydrogen (up to several hundred ppm) have been detected in olivine, orthopyroxene, clinopyroxene, and garnet recovered from xenoliths in kimberlites, eclogites, and alkali basalts; it has been demonstrated that synthetic wadsleyite and perovskite can accommodate significant amounts of hydrogen. A number of problems are associated with each possibility. For NAM originating in the mantle, one would like to assume that the hydrogen measured in samples recovered on Earth's surface was incorporated when the phase-crystallized at high temperatures and pressures, but it could have been introduced during transport to the surface. Major problems for the DHMS proponents are that none of these phases have been found as minerals and little is yet known about their stabilities in systems containing other cations such as Fe, Al, and Ca. 2. Charged fullerenes as high-capacity hydrogen storage media. PubMed Yoon, Mina; Yang, Shenyuan; Wang, Enge; Zhang, Zhenyu 2007-09-01 Using first-principles calculations within density functional theory, we explore systematically the capacity of charged carbon fullerenes Cn (20 hydrogen storage media. We find that the binding strength of molecular hydrogen on either positively or negatively charged fullerenes can be dramatically enhanced to 0.18-0.32 eV, a desirable range for potential room-temperature, near ambient applications. The enhanced binding is delocalized in nature, surrounding the whole surface of a charged fullerene, and is attributed to the polarization of the hydrogen molecules by the high electric field generated near the surface of the charged fullerene. At full hydrogen coverage, these charged fullerenes can gain storage capacities of up to approximately 8.0 wt %. We also find that, contrary to intuitive expectation, fullerenes containing encapsulated metal atoms only exhibit negligible enhancement in the hydrogen binding strength, because the charge donated by the metal atoms is primarily confined inside the fullerene cages. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage media. 3. Clay-supported graphene materials: application to hydrogen storage. PubMed Ruiz-García, Cristina; Pérez-Carvajal, Javier; Berenguer-Murcia, Angel; Darder, Margarita; Aranda, Pilar; Cazorla-Amorós, Diego; Ruiz-Hitzky, Eduardo 2013-11-14 The present work refers to clay-graphene nanomaterials prepared by a green way using caramel from sucrose and two types of natural clays (montmorillonite and sepiolite) as precursors, with the aim of evaluating their potential use in hydrogen storage. The impregnation of the clay substrates by caramel in aqueous media, followed by a thermal treatment in the absence of oxygen of these clay-caramel intermediates gives rise to graphene-like materials, which remain strongly bound to the silicate support. The nature of the resulting materials was characterized by different techniques such as XRD, Raman spectroscopy and TEM, as well as by adsorption isotherms of N2, CO2 and H2O. These carbon-clay nanocomposites can act as adsorbents for hydrogen storage, achieving, at 298 K and 20 MPa, over 0.1 wt% of hydrogen adsorption excess related to the total mass of the system, and a maximum value close to 0.4 wt% of hydrogen specifically related to the carbon mass. The very high isosteric heat for hydrogen sorption determined from adsorption isotherms at different temperatures (14.5 kJ mol(-1)) fits well with the theoretical values available for hydrogen storage on materials that show a strong stabilization of the H2 molecule upon adsorption. 4. Strategies for Hydrogen Storage in Nanoporous Metal-Organic Framework Materials NASA Astrophysics Data System (ADS) Snurr, Randall 2011-03-01 Storing hydrogen by physisorption in porous materials is a challenging problem of great interest for future vehicle technology. Metal-organic frameworks (MOFs) are a new class of nanoporous materials that have demonstrated exciting potential for solving this problem. MOFs are synthesized by the self-assembly of metal nodes and connecting organic linker molecules to create stable, porous frameworks. The synthetic chemistry opens the possibility to create an almost unlimited number of MOFs and to tailor them for particular applications, such as hydrogen storage. The diversity of MOFs also creates an opportunity to learn more about the fundamentals of hydrogen adsorption in porous materials. We have used a combination of classical Monte Carlo simulations and quantum mechanical approaches to investigate fundamental questions about hydrogen storage in MOFs and to design new materials with improved storage capabilities. Relationships have been elucidated between hydrogen uptake and properties such as the MOF surface area, void volume, degree of catenation, enthalpy of adsorption, and cation content. Introduction of cations is a promising strategy to improve hydrogen uptake at room temperature, and different metal cations and different strategies for introducing them into MOFs have been screened computationally. 5. Second Generation MOF's for Hydrogen Storage SciTech Connect Adam Matzger 2008-05-31 This final technical report summarizes work exploring strategies to generate second generation metal organic frameworks (MOFs). These strategies were (a) the formation of interpenetrated frameworks and (b) the generation of coordinatively unsaturated metal centers (open metal sites). In the first phase of the project the effectiveness of these strategies was evaluated experimentally by measuring the saturation hydrogen uptake at high pressure and low temperature of 14 MOFs. The results of these studies demonstrated that surface area is the most useful parameter that correlates with ultimate hydrogen capacity. The strategy of interpenetration has so far failed to produce MOFs with high surface areas and therefore high saturation capacities for hydrogen have not been achieved. The incorporation of coordinatively unsaturated metal centers, however, is a promising strategy that allows higher heats of H2 adsorption to be realized without compromising surface area. Based on these initial findings, research efforts in phase two have concentrated on the discovery of new ultrahigh surface area materials with metal centers capable of supporting coordinative unsaturation without structural collapse. One approach has been the synthesis of new organic linkers that have more exposed edges, which is a factor that contributes to increasing surface area, at least when considering subunits of graphene sheets. Another strategy has been to synthesize MOFs with reduced symmetry linkers in order to generate structure types that are less likely to interpenetrate. Successful implementation of these strategies has resulted in the synthesis of 7 new compounds one of which is the highest surface area Cu based MOF reported to date. 6. Hydrogen storage by physisorption on Metal Organic Frameworks NASA Astrophysics Data System (ADS) Dailly, Anne 2008-03-01 Cryo-adsorption systems based on materials with high specific surface areas have the main advantage that they can store and release hydrogen with fast kinetics and high reversibility over multiples cycles. Recently Metal Organic Frameworks (MOFs) have been proposed as promising adsorbents for hydrogen. These crystallographically well organized hybrid solids resulting from the three dimensional connection of inorganic clusters using organic linkers show the largest specific surface areas of all known crystalline solids. The determination of the relationships between physical properties (chemistry, structure, surface area ) of the MOFs and their hydrogen storage behavior is a key step in the characterization of these materials, if they are to be designed for hydrogen storage applications. Excess hydrogen sorption measurements for different MOFs will be presented. We show that maximum hydrogen uptake at high pressure and 77K does not always scale with the specific surface area. A linear correlation trend only apply within a class of specific materials and breaks down when the surface area measurement does not represent the surface sites that are available to H2. The influence of pore size and shape will also be discussed by comparing several MOFs with different structure types. The hydrogen adsorption and binding energy at low pressure are strongly dependent on the metal ions and the pore size. 7. Feasibility and induced effects of subsurface porous media hydrogen storage NASA Astrophysics Data System (ADS) Tilmann Pfeiffer, Wolf; Li, Dedong; Wang, Bo; Bauer, Sebastian 2015-04-01 Fluctuations in energy production from renewable sources like wind or solar power can lead to shortages in energy supply which can be mitigated using energy storage concepts. Underground storage of hydrogen in porous sandstone formations could be a storage option for large amounts of energy over long storage cycles. However, this use of the subsurface requires an analysis of possible interactions with other uses of the subsurface such as geothermal energy storage or groundwater abstraction. This study aims at quantifying the feasibility of porous media hydrogen storage to provide stored energy on a timescale of several days to weeks as well as possible impacts on the subsurface. The hypothetical storage site is based on an anticlinal structure located in Schleswig-Holstein, northern Germany. The storage is injected and extracted using five wells completed in a partially eroded, heterogeneous sandstone layer in the top of the structure at a depth of about 500 m. The storage formation was parameterized based on a local facies model with intrinsic permeabilities of 250-2500 mD and porosities of 35-40%. Storage initialization and subsequent storage cycles, each consisting of a hydrogen injection and extraction, were numerically simulated. The simulation results indicate the general feasibility of this hydrogen storage concept. The simulated sandstone formation is able to provide an average of around 1480 t of hydrogen per week (1830 TJ) which is about 5% of the total weekly energy production or about 10% of the weekly energy consumption of Schleswig-Holstein with the hydrogen production rate being the limiting factor of the overall performance. Induced hydraulic effects are a result of the induced overpressure within the storage formation. Propagation of the pressure signal does not strongly depend on the formation heterogeneity and thus shows approximately radial characteristics with one bar pressure change in distances of about 5 km from the injection wells. Thermal 8. Technoeconomic analysis of renewable hydrogen production, storage, and detection systems SciTech Connect Mann, M.K.; Spath, P.L.; Kadam, K. 1996-10-01 Technical and economic feasibility studies of different degrees of completeness and detail have been performed on several projects being funded by the Department of Energys Hydrogen Program. Work this year focused on projects at the National Renewable Energy Laboratory, although analyses of projects at other institutions are underway or planned. Highly detailed analyses were completed on a fiber optic hydrogen leak detector and a process to produce hydrogen from biomass via pyrolysis followed by steam reforming of the pyrolysis oil. Less detailed economic assessments of solar and biologically-based hydrogen production processes have been performed and focused on the steps that need to be taken to improve the competitive position of these technologies. Sensitivity analyses were conducted on all analyses to reveal the degree to which the cost results are affected by market changes and technological advances. For hydrogen storage by carbon nanotubes, a survey of the competing storage technologies was made in order to set a baseline for cost goals. A determination of the likelihood of commercialization was made for nearly all systems examined. Hydrogen from biomass via pyrolysis and steam reforming was found to have significant economic potential if a coproduct option could be co-commercialized. Photoelectrochemical hydrogen production may have economic potential, but only if low-cost cells can be modified to split water and to avoid surface oxidation. The use of bacteria to convert the carbon monoxide in biomass syngas to hydrogen was found to be slightly more expensive than the high end of currently commercial hydrogen, although there are significant opportunities to reduce costs. Finally, the cost of installing a fiber-optic chemochromic hydrogen detection system in passenger vehicles was found to be very low and competitive with alternative sensor systems. 9. A hydrogen storage nanotank: lithium-organic pillared graphite. PubMed Han, Sang Soo; Jang, Seung Soon 2009-09-28 From first-principle based grand canonical Monte-Carlo simulations, we propose a new hydrogen storage material, lithium-organic pillared graphite, showing high H2 uptake of 4.0 wt% and 41.9 kg m(-3) at 300 K and 100 bar. 10. 20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, ... Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey 20. DECOMMISIONED HYDROGEN TANK IN FORMER LIQUID OXYGEN STORAGE AREA, BETWEEN TEST STAND 1-A AND INSTRUMENTATION AND CONTROL BUILDING. Looking northwest. - Edwards Air Force Base, Air Force Rocket Propulsion Laboratory, Test Stand 1-A, Test Area 1-120, north end of Jupiter Boulevard, Boron, Kern County, CA 11. Parameter study of a vehicle-scale hydrogen storage system. SciTech Connect Johnson, Terry Alan; Kanouff, Michael P. 2010-04-01 Sandia National Laboratories has developed a vehicle-scale prototype hydrogen storage system as part of a Work For Others project funded by General Motors. This Demonstration System was developed using the complex metal hydride sodium alanate. For the current work, we have continued our evaluation of the GM Demonstration System to provide learning to DOE's hydrogen storage programs, specifically the new Hydrogen Storage Engineering Center of Excellence. Baseline refueling data during testing for GM was taken over a narrow range of optimized parameter values. Further testing was conducted over a broader range. Parameters considered included hydrogen pressure and coolant flow rate. This data confirmed the choice of design pressure of the Demonstration System, but indicated that the system was over-designed for cooling. Baseline hydrogen delivery data was insufficient to map out delivery rate as a function of temperature and capacity for the full-scale system. A more rigorous matrix of tests was performed to better define delivery capabilities. These studies were compared with 1-D and 2-D coupled multi-physics modeling results. The relative merits of these models are discussed along with opportunities for improved efficiency or reduced mass and volume. 12. Hydrogen storage reactions on titanium decorated carbon nanocones theoretical study NASA Astrophysics Data System (ADS) Shalabi, A. S.; Taha, H. O.; Soliman, K. A.; Abeld Aal, S. 2014-12-01 Hydrogen storage reactions on Ti decorated carbon nanocones (CNC) are investigated by using the state of the art density functional theory calculations. The single Ti atom prefers to bind at the bridge site between two hexagonal rings, and can bind up to 6 hydrogen molecules with average adsorption energies of -1.73, -0.74, -0.57, -0.45, -0.42, and -0.35 eV per hydrogen molecule. No evidence for metal clustering in the ideal circumstances, and the hydrogen storage capacity is expected to be as large as 14.34 wt%. Two types of interactions are recognized. While the interaction of 2H2 with Ti-CNC is irreversible at 532 K, the interaction of 3H2 with Ti-CNC is reversible at 392 K. Further characterizations of the former two reactions are considered in terms of projected densities of states, simulated infrared and proton magnetic resonance spectra, electrophilicity, and statistical thermodynamic stability. The free energy of the highest hydrogen storage capacity reaction between 6H2 and Ti-CNC meets the ultimate targets of department of energy at (233.15 K) and (11.843 atm) with surface coverage (0.941) and (direct/inverse) rate constants ratio (1.35). 13. Hollow porous-wall glass microspheres for hydrogen storage DOEpatents Heung, Leung K.; Schumacher, Ray F.; Wicks, George G. 2010-02-23 A porous wall hollow glass microsphere is provided having a diameter range of between 1 to 200 microns, a density of between 1.0 to 2.0 gm/cc, a porous-wall structure having wall openings defining an average pore size of between 10 to 1000 angstroms, and which contains therein a hydrogen storage material. The porous-wall structure facilitates the introduction of a hydrogen storage material into the interior of the porous wall hollow glass microsphere. In this manner, the resulting hollow glass microsphere can provide a membrane for the selective transport of hydrogen through the porous walls of the microsphere, the small pore size preventing gaseous or liquid contaminants from entering the interior of the hollow glass microsphere. 14. Hollow Li20B60 Cage: Stability and Hydrogen Storage PubMed Central Wang, Jing; Wei, Zhi-Jing; Zhao, Hui-Yan; Liu, Ying 2016-01-01 A stable hollow Li20B60 cage with D2 symmetry has been identified using first-principles density functional theory studies. The results of vibrational frequency analysis and molecular dynamics simulations demonstrate that this Li20B60 cage is exceptionally stable. The feasibility of functionalizing Li20B60 cage for hydrogen storage was explored theoretically. Our calculated results show that the Li20B60 molecule can adsorb a maximum of 28 hydrogen molecules. With a hydrogen uptake of 8.190 wt% and an average binding energy of 0.336 eV/H2, Li20B60 is a remarkable high-capacity storage medium. PMID:27076264 15. Hollow Li20B60 Cage: Stability and Hydrogen Storage. PubMed Wang, Jing; Wei, Zhi-Jing; Zhao, Hui-Yan; Liu, Ying 2016-04-14 A stable hollow Li20B60 cage with D2 symmetry has been identified using first-principles density functional theory studies. The results of vibrational frequency analysis and molecular dynamics simulations demonstrate that this Li20B60 cage is exceptionally stable. The feasibility of functionalizing Li20B60 cage for hydrogen storage was explored theoretically. Our calculated results show that the Li20B60 molecule can adsorb a maximum of 28 hydrogen molecules. With a hydrogen uptake of 8.190 wt% and an average binding energy of 0.336 eV/H2, Li20B60 is a remarkable high-capacity storage medium. 16. Experimental design and simulation of a metal hydride hydrogen storage system NASA Astrophysics Data System (ADS) Gadre, Sarang Ajit Metal hydrides, as a hydrogen storage medium, have been under consideration for many years because they have the ability to store hydrogen reversibly in the solid state at relatively low pressures and ambient temperatures. The utility of metal hydrides as a hydrogen storage medium was demonstrated recently by the Savannah River Technology Center (SRTC) in an on-board hydrogen storage system for a hybrid electric bus project. The complex geometry and the intricate design of the SRTC bed presents quite a challenge to the development of a mathematical model that can be used for design and optimization. In a new approach introduced here, the reversible reaction kinetics and the empirical Van't Hoff relationship used in a typical reactor model are replaced by a solid phase diffusion equation and one of the two semi-empirical equilibrium P-C-T relationships based on modified virial and composite Langmuir isotherm expressions. Starting with the simplest mathematical formulation, which resulted in an analytical expression, various models were developed and successively improved by relaxing certain assumptions, eventually resulting in the most rigorous model yet developed for this system. All of these models were calibrated using experimental pressure and temperature histories obtained from a bench scale hydrogen storage test facility. The heat and mass transfer coefficients or the thermal conductivity were the only adjustable parameters in these models. A design of experiments approach was also used for studying the effect of various factors on the performance of this bench scale hydrogen storage unit. Overall, the results of this study demonstrated that even a fairly simple numerical model could do a reasonable job in predicting the discharge behavior of a fairly complicated, metal hydride hydrogen storage bed over a wide range of operating conditions. The more rigorous 2-D model gave considerable insight into the dynamics of the hydrogen discharge process from an 17. Mg-based compounds for hydrogen and energy storage NASA Astrophysics Data System (ADS) Crivello, J.-C.; Denys, R. V.; Dornheim, M.; Felderhoff, M.; Grant, D. M.; Huot, J.; Jensen, T. R.; de Jongh, P.; Latroche, M.; Walker, G. S.; Webb, C. J.; Yartys, V. A. 2016-02-01 Magnesium-based alloys attract significant interest as cost-efficient hydrogen storage materials allowing the combination of high gravimetric storage capacity of hydrogen with fast rates of hydrogen uptake and release and pronounced destabilization of the metal-hydrogen bonding in comparison with binary Mg-H systems. In this review, various groups of magnesium compounds are considered, including (1) RE-Mg-Ni hydrides (RE = La, Pr, Nd); (2) Mg alloys with p-elements (X = Si, Ge, Sn, and Al); and (3) magnesium alloys with d-elements (Ti, Fe, Co, Ni, Cu, Zn, Pd). The hydrogenation-disproportionation-desorption-recombination process in the Mg-based alloys (LaMg12, LaMg11Ni) and unusually high-pressure hydrides synthesized at pressures exceeding 100 MPa (MgNi2H3) and stabilized by Ni-H bonding are also discussed. The paper reviews interrelations between the properties of the Mg-based hydrides and p- T conditions of the metal-hydrogen interactions, chemical composition of the initial alloys, their crystal structures, and microstructural state. 18. Life-Cycle Cost Analysis Highlights Hydrogen's Potential for Electrical Energy Storage (Fact Sheet) SciTech Connect Not Available 2010-11-01 This fact sheet describes NREL's accomplishments in analyzing life-cycle costs for hydrogen storage in comparison with other energy storage technologies. Work was performed by the Hydrogen Technologies and Systems Center. 19. Microscale Enhancement of Heat and Mass Transfer for Hydrogen Energy Storage SciTech Connect Drost, Kevin; Jovanovic, Goran; Paul, Brian 2015-09-30 The document summarized the technical progress associated with OSU’s involvement in the Hydrogen Storage Engineering Center of Excellence. OSU focused on the development of microscale enhancement technologies for improving heat and mass transfer in automotive hydrogen storage systems. OSU’s key contributions included the development of an extremely compact microchannel combustion system for discharging hydrogen storage systems and a thermal management system for adsorption based hydrogen storage using microchannel cooling (the Modular Adsorption Tank Insert or MATI). 20. System level permeability modeling of porous hydrogen storage materials. SciTech Connect Kanouff, Michael P.; Dedrick, Daniel E.; Voskuilen, Tyler 2010-01-01 A permeability model for hydrogen transport in a porous material is successfully applied to both laboratory-scale and vehicle-scale sodium alanate hydrogen storage systems. The use of a Knudsen number dependent relationship for permeability of the material in conjunction with a constant area fraction channeling model is shown to accurately predict hydrogen flow through the reactors. Generally applicable model parameters were obtained by numerically fitting experimental measurements from reactors of different sizes and aspect ratios. The degree of channeling was experimentally determined from the measurements and found to be 2.08% of total cross-sectional area. Use of this constant area channeling model and the Knudsen dependent Young & Todd permeability model allows for accurate prediction of the hydrogen uptake performance of full-scale sodium alanate and similar metal hydride systems. 1. Destabilized and catalyzed borohydride for reversible hydrogen storage DOEpatents Mohtadi, Rana F.; Nakamura, Kenji; Au, Ming; Zidan, Ragaiy 2012-01-31 A process of forming a hydrogen storage material, including the steps of: providing a first material of the formula M(BH.sub.4).sub.X, where M is an alkali metal or an alkali earth metal, providing a second material selected from M(AlH.sub.4).sub.x, a mixture of M(AlH.sub.4).sub.x and MCl.sub.x, a mixture of MCl.sub.x and Al, a mixture of MCl.sub.x and AlH.sub.3, a mixture of MH.sub.x and Al, Al, and AlH.sub.3. The first and second materials are combined at an elevated temperature and at an elevated hydrogen pressure for a time period forming a third material having a lower hydrogen release temperature than the first material and a higher hydrogen gravimetric density than the second material. 2. Technology Development for Hydrogen Propellant Storage and Transfer at the Kennedy Space Center (KSC) NASA Technical Reports Server (NTRS) Youngquist, Robert; Starr, Stanley; Krenn, Angela; Captain, Janine; Williams, Martha 2016-01-01 The National Aeronautics and Space Administration (NASA) is a major user of liquid hydrogen. In particular, NASA's John F. Kennedy (KSC) Space Center has operated facilities for handling and storing very large quantities of liquid hydrogen (LH2) since the early 1960s. Safe operations pose unique challenges and as a result NASA has invested in technology development to improve operational efficiency and safety. This paper reviews recent innovations including methods of leak and fire detection and aspects of large storage tank health and integrity. We also discuss the use of liquid hydrogen in space and issues we are addressing to ensure safe and efficient operations should hydrogen be used as a propellant derived from in-situ volatiles. 3. Conceptual design of a hydrogen storage system for a Mars Sample Return mission NASA Astrophysics Data System (ADS) Mueller, Paul John, III A Mars Sample Return mission concept under consideration by NASA uses carbon dioxide from the Martian atmosphere, in combination with hydrogen brought from Earth, to create oxygen and methane propellants for the return trip. This may allow launch from Earth on a smaller, less expensive launch vehicle. A major engineering challenge for this concept is to design a system that can store the hydrogen during the 8-month trip to Mars. A wide variety of design options was considered, including solid, liquid, or slush hydrogen, tank materials, insulation configurations, etc. A comprehensive computer simulation program was written and used to arrive at a preferred hydrogen storage system conceptual design, optimized in terms of mass, insulation thickness, maximum tank pressure, and tank volume. The feasibility of this concept in terms of total spacecraft mass could not be firmly established; however, it appeared very promising and worthy of further development. 4. Glass Bubbles Insulation for Liquid Hydrogen Storage Tanks NASA Technical Reports Server (NTRS) Sass, J. P.; SaintCyr, W. W.; Barrett, T. M.; Baumgartner, R. G.; Lott, J. W.; Fesmire, J. E. 2009-01-01 A full-scale field application of glass bubbles insulation has been demonstrated in a 218,000 L liquid hydrogen storage tank. This work is the evolution of extensive materials testing, laboratory scale testing, and system studies leading to the use of glass bubbles insulation as a cost efficient and high performance alternative in cryogenic storage tanks of any size. The tank utilized is part of a rocket propulsion test complex at the NASA Stennis Space Center and is a 1960's vintage spherical double wall tank with an evacuated annulus. The original perlite that was removed from the annulus was in pristine condition and showed no signs of deterioration or compaction. Test results show a significant reduction in liquid hydrogen boiloff when compared to recent baseline data prior to removal of the perlite insulation. The data also validates the previous laboratory scale testing (1000 L) and full-scale numerical modeling (3,200,000 L) of boiloff in spherical cryogenic storage tanks. The performance of the tank will continue to be monitored during operation of the tank over the coming years. KEYWORDS: Glass bubble, perlite, insulation, liquid hydrogen, storage tank. 5. The challenge of a data storage hierarchy NASA Technical Reports Server (NTRS) Ruderman, Michael 1992-01-01 A discussion of Mesa Archival Systems' data archiving system is presented. This data archiving system is strictly a software system that is implemented on a mainframe and manages the data into permanent file storage. Emphasis is placed on the fact that any kind of client system on the network can be connected through the Unix interface of the data archiving system. 6. New Pathways and Metrics for Enhanced, Reversible Hydrogen Storage in Boron-Doped Carbon Nanospaces SciTech Connect Pfeifer, Peter; Wexler, Carlos; Hawthorne, M. Frederick; Lee, Mark W.; Jalistegi, Satish S. 2014-08-14 This project, since its start in 2007—entitled “Networks of boron-doped carbon nanopores for low-pressure reversible hydrogen storage” (2007-10) and “New pathways and metrics for enhanced, reversible hydrogen storage in boron-doped carbon nanospaces” (2010-13)—is in support of the DOE's National Hydrogen Storage Project, as part of the DOE Hydrogen and Fuel Cells Program’s comprehensive efforts to enable the widespread commercialization of hydrogen and fuel cell technologies in diverse sectors of the economy. Hydrogen storage is widely recognized as a critical enabling technology for the successful commercialization and market acceptance of hydrogen powered vehicles. Storing sufficient hydrogen on board a wide range of vehicle platforms, at energy densities comparable to gasoline, without compromising passenger or cargo space, remains an outstanding technical challenge. Of the main three thrust areas in 2007—metal hydrides, chemical hydrogen storage, and sorption-based hydrogen storage—sorption-based storage, i.e., storage of molecular hydrogen by adsorption on high-surface-area materials (carbons, metal-organic frameworks, and other porous organic networks), has emerged as the most promising path toward achieving the 2017 DOE storage targets of 0.055 kg H2/kg system (“5.5 wt%”) and 0.040 kg H2/liter system. The objective of the project is to develop high-surface-area carbon materials that are boron-doped by incorporation of boron into the carbon lattice at the outset, i.e., during the synthesis of the material. The rationale for boron-doping is the prediction that boron atoms in carbon will raise the binding energy of hydro- gen from 4-5 kJ/mol on the undoped surface to 10-14 kJ/mol on a doped surface, and accordingly the hydro- gen storage capacity of the material. The mechanism for the increase in binding energy is electron donation from H2 to electron-deficient B atoms, in the form of sp2 boron-carbon bonds. Our team is proud to have 7. Formic acid as a hydrogen storage material - development of homogeneous catalysts for selective hydrogen release. PubMed Mellmann, Dörthe; Sponholz, Peter; Junge, Henrik; Beller, Matthias 2016-07-11 Formic acid (FA, HCO2H) receives considerable attention as a hydrogen storage material. In this respect, hydrogenation of CO2 to FA and dehydrogenation of FA are crucial reaction steps. In the past decade, for both reactions, several molecularly defined and nanostructured catalysts have been developed and intensively studied. From 2010 onwards, this review covers recent advancements in this area using homogeneous catalysts. In addition to the development of catalysts for H2 generation, reversible H2 storage including continuous H2 production from formic acid is highlighted. Special focus is put on recent progress in non-noble metal catalysts. 8. Low Cost, High Efficiency, High Pressure Hydrogen Storage SciTech Connect Mark Leavitt 2010-03-31 A technical and design evaluation was carried out to meet DOE hydrogen fuel targets for 2010. These targets consisted of a system gravimetric capacity of 2.0 kWh/kg, a system volumetric capacity of 1.5 kWh/L and a system cost of4/kWh. In compressed hydrogen storage systems, the vast majority of the weight and volume is associated with the hydrogen storage tank. In order to meet gravimetric targets for compressed hydrogen tanks, 10,000 psi carbon resin composites were used to provide the high strength required as well as low weight. For the 10,000 psi tanks, carbon fiber is the largest portion of their cost. Quantum Technologies is a tier one hydrogen system supplier for automotive companies around the world. Over the course of the program Quantum focused on development of technology to allow the compressed hydrogen storage tank to meet DOE goals. At the start of the program in 2004 Quantum was supplying systems with a specific energy of 1.1-1.6 kWh/kg, a volumetric capacity of 1.3 kWh/L and a cost of $73/kWh. Based on the inequities between DOE targets and Quantum’s then current capabilities, focus was placed first on cost reduction and second on weight reduction. Both of these were to be accomplished without reduction of the fuel system’s performance or reliability. Three distinct areas were investigated; optimization of composite structures, development of “smart tanks” that could monitor health of tank thus allowing for lower design safety factor, and the development of “Cool Fuel” technology to allow higher density gas to be stored, thus allowing smaller/lower pressure tanks that would hold the required fuel supply. The second phase of the project deals with three additional distinct tasks focusing on composite structure optimization, liner optimization, and metal. 9. Polymeric hydrogen diffusion barrier, high-pressure storage tank so equipped, method of fabricating a storage tank and method of preventing hydrogen diffusion DOEpatents Lessing, Paul A. 2004-09-07 An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed. 10. Polymeric hydrogen diffusion barrier, high-pressure storage tank so equipped, method of fabricating a storage tank and method of preventing hydrogen diffusion DOEpatents Lessing, Paul A. 2008-07-22 An electrochemically active hydrogen diffusion barrier which comprises an anode layer, a cathode layer, and an intermediate electrolyte layer, which is conductive to protons and substantially impermeable to hydrogen. A catalytic metal present in or adjacent to the anode layer catalyzes an electrochemical reaction that converts any hydrogen that diffuses through the electrolyte layer to protons and electrons. The protons and electrons are transported to the cathode layer and reacted to form hydrogen. The hydrogen diffusion barrier is applied to a polymeric substrate used in a storage tank to store hydrogen under high pressure. A storage tank equipped with the electrochemically active hydrogen diffusion barrier, a method of fabricating the storage tank, and a method of preventing hydrogen from diffusing out of a storage tank are also disclosed. 11. Hydrogen Storage Needs for Early Motive Fuel Cell Markets SciTech Connect Kurtz, J.; Ainscough, C.; Simpson, L.; Caton, M. 2012-11-01 The National Renewable Energy Laboratory's (NREL) objective for this project is to identify performance needs for onboard energy storage of early motive fuel cell markets by working with end users, manufacturers, and experts. The performance needs analysis is combined with a hydrogen storage technology gap analysis to provide the U.S. Department of Energy (DOE) Fuel Cell Technologies Program with information about the needs and gaps that can be used to focus research and development activities that are capable of supporting market growth. 12. Lifecycle Cost Analysis of Hydrogen Versus Other Technologies for Electrical Energy Storage SciTech Connect Steward, D.; Saur, G.; Penev, M.; Ramsden, T. 2009-11-01 This report presents the results of an analysis evaluating the economic viability of hydrogen for medium- to large-scale electrical energy storage applications compared with three other storage technologies: batteries, pumped hydro, and compressed air energy storage (CAES). 13. Boron–nitrogen–hydrogen (BNH) compounds: recent developments in hydrogen storage, applications in hydrogenation and catalysis, and new syntheses SciTech Connect Huang, Zhenguo; Autrey, Tom 2012-09-01 The strong efforts devoted to the exploration of BNH compounds for hydrogen storage have led to impressive advances in the field of boron chemistry. This review summarizes progress in this field from three aspects. It starts with the most recent developments in using BNH compounds for hydrogen storage, covering NH3BH3, B3H8- containing compounds, and CBN compounds. The following section then highlights interesting applications of BNH compounds in hydrogenation and catalysis. The last part is focused on breakthroughs in the syntheses and discovery of new BNH organic analogues. Finally, the role of N–Hδ+∙∙∙Hδ-–B dihydrogen interactions in molecule packing, thermal hydrogen evolution, and syntheses is also discussed within the review. 14. Process for synthesis of ammonia borane for bulk hydrogen storage SciTech Connect Autrey, S Thomas; Heldebrant, David J; Linehan, John C; Karkamkar, Abhijeet J; Zheng, Feng 2011-03-01 The present invention discloses new methods for synthesizing ammonia borane (NH.sub.3BH.sub.3, or AB). Ammonium borohydride (NH.sub.4BH.sub.4) is formed from the reaction of borohydride salts and ammonium salts in liquid ammonia. Ammonium borohydride is decomposed in an ether-based solvent that yields AB at a near quantitative yield. The AB product shows promise as a chemical hydrogen storage material for fuel cell powered applications. 15. Hydrogen-Oxygen PEM Regenerative Fuel Cell Energy Storage System NASA Technical Reports Server (NTRS) Bents, David J.; Scullin, Vincent J.; Chang, Bei-Jiann; Johnson, Donald W.; Garcia, Christopher P. 2005-01-01 An introduction to the closed cycle hydrogen-oxygen polymer electrolyte membrane (PEM) regenerative fuel cell (RFC), recently constructed at NASA Glenn Research Center, is presented. Illustrated with explanatory graphics and figures, this report outlines the engineering motivations for the RFC as a solar energy storage device, the system requirements, layout and hardware detail of the RFC unit at NASA Glenn, the construction history, and test experience accumulated to date with this unit. 16. Durability study of a vehicle-scale hydrogen storage system. SciTech Connect Johnson, Terry Alan; Dedrick, Daniel E.; Behrens, Richard, Jr. 2010-11-01 Sandia National Laboratories has developed a vehicle-scale demonstration hydrogen storage system as part of a Work for Others project funded by General Motors. This Demonstration System was developed based on the properties and characteristics of sodium alanates which are complex metal hydrides. The technology resulting from this program was developed to enable heat and mass management during refueling and hydrogen delivery to an automotive system. During this program the Demonstration System was subjected to repeated hydriding and dehydriding cycles to enable comparison of the vehicle-scale system performance to small-scale sample data. This paper describes the experimental results of life-cycle studies of the Demonstration System. Two of the four hydrogen storage modules of the Demonstration System were used for this study. A well-controlled and repeatable sorption cycle was defined for the repeated cycling, which began after the system had already been cycled forty-one times. After the first nine repeated cycles, a significant hydrogen storage capacity loss was observed. It was suspected that the sodium alanates had been affected either morphologically or by contamination. The mechanisms leading to this initial degradation were investigated and results indicated that water and/or air contamination of the hydrogen supply may have lead to oxidation of the hydride and possibly kinetic deactivation. Subsequent cycles showed continued capacity loss indicating that the mechanism of degradation was gradual and transport or kinetically limited. A materials analysis was then conducted using established methods including treatment with carbon dioxide to react with sodium oxides that may have formed. The module tubes were sectioned to examine chemical composition and morphology as a function of axial position. The results will be discussed. 17. Vehicular hydrogen storage using lightweight tanks (regenerative fuel cell systems) SciTech Connect Mitlitsky, F; Myers, B; Weisberg, A H 1999-06-01 Energy storage systems with extremely high specific energy (>400 Wh/kg) have been designed that use lightweight tankage to contain the gases generated by reversible (unitized) regenerative fuel cells (URFCs). Lawrence Livermore National Laboratory (LLNL) will leverage work for aerospace applications supported by other sponsors (including BMDO, NASA, and USAF) to develop URFC systems for transportation and utility applications. Lightweight tankage is important for primary fuel cell powered vehicles that use on-board storage of hydrogen. Lightweight pressure vessels with state-of-the-art performance factors were designed, and prototypes are being fabricated to meet the DOE 2000 goals (4000 Wh/kg, 12% hydrogen by weight, 700 Wh/liter, and$20/kWh in high volume production). These pressure vessels use technologies that are easily adopted by industrial partners. Advanced liners provide permeation barriers for gas storage and are mandrels for composite overwrap. URFCs are important to the efficient use of hydrogen as a transportation fuel and enabler of renewable energy. H{sub 2}/halogen URFCs may be advantageous for stationary applications whereas H{sub 2}/O{sub 2} or H{sub 2}/air URFCs are advantageous for vehicular applications. URFC research and development is required to improve performance (efficiency), reduce catalyst loading, understand engineering operation, and integrate systems. LLNL has the experimental equipment and advanced URFC membrane electrode assemblies (some with reduced catalyst loading) for evaluating commercial hardware (not funded by DOE in FY1999).

18. Storage of Hydrogen in Single-Walled Carbon Nanotubes

SciTech Connect

Dillon, A. C.; Jones, K. M.; Bekkedahl, T. A.; Kiang, C. H.; Bethune, D. S.; Heben, M. J.

1997-03-27

Pores of molecular dimensions can adsorb large quantities of gases owing to the enhanced density of the adsorbed material inside the pores, a consequence of the attractive potential of the pore walls. Pederson and Broughton have suggested that carbon nanotubes, which have diameters of typically a few nanometres, should be able to draw up liquids by capillarity, and this effect has been seen for low-surface-tension liquids in large-diameter, multi-walled nanotubes. Here we show that a gas can condense to high density inside narrow, single-walled nanotubes (SWNTs). Temperature-programmed desorption spectroscopy shows that hydrogen will condense inside SWNTs under conditions that do not induce adsorption within a standard mesoporous activated carbon. The very high hydrogen uptake in these materials suggests that they might be effective as a hydrogen-storage material for fuel-cell electric vehicles.

19. Hydrogen storage in fullerenes and in an organic hydride

SciTech Connect

Wang, J.C.; Murphy, R.W.; Chen, F.C.; Loutfy, R.O.; Veksler, E.; Li, W.

1998-05-29

While the authors have demonstrated the importance and usefulness of thermal management to the hydrogen storage in fullerenes, their recent effort has concentrated on materials improvement and physical model development. In this paper, they report the results of this effort as follows: (1) Liquid phase hydrogenation of fullerenes indicated that more than 6 wt% capacity can be obtained at 180 C, 350--400 psi; (2) Dehydrogenation of fullerenes hydrides below 225 C was demonstrated using an Ir-based P-C-P pincer complex catalyst; (3) Cyclic hydrogenation and dehydrogenation tests of an organic hydride at 7 wt% capacity were conducted at 180--260 C; and (4) Physical models developed for fullerenes were determined to be applicable to this organic hydride (with much smaller activation energies).

20. Hydrogen storage in high surface area graphene scaffolds.

PubMed

Klechikov, Alexey; Mercier, Guillaume; Sharifi, Tiva; Baburin, Igor A; Seifert, Gotthard; Talyzin, Alexandr V

2015-10-25

Using an optimized KOH activation procedure we prepared highly porous graphene scaffold materials with SSA values up to 3400 m(2) g(-1) and a pore volume up to 2.2 cm(3) g(-1), which are among the highest for carbon materials. Hydrogen uptake of activated graphene samples was evaluated in a broad temperature interval (77-296 K). After additional activation by hydrogen annealing the maximal excess H2 uptake of 7.5 wt% was obtained at 77 K. A hydrogen storage value as high as 4 wt% was observed already at 193 K (120 bar H2), a temperature of solid CO2, which can be easily maintained using common industrial refrigeration methods.

1. Development of Regenerable High Capacity Boron Nitrogen Hydrides as Hydrogen Storage Materials

SciTech Connect

Damle, A.

2010-02-03

The objective of this three-phase project is to develop synthesis and hydrogen extraction processes for nitrogen/boron hydride compounds that will permit exploitation of the high hydrogen content of these materials. The primary compound of interest in this project is ammonia-borane (NH{sub 3}BH{sub 3}), a white solid, stable at ambient conditions, containing 19.6% of its weight as hydrogen. With a low-pressure on-board storage and an efficient heating system to release hydrogen, ammonia-borane has a potential to meet DOE's year 2015 specific energy and energy density targets. If the ammonia-borane synthesis process could use the ammonia-borane decomposition products as the starting raw material, an efficient recycle loop could be set up for converting the decomposition products back into the starting boron-nitrogen hydride. This project is addressing two key challenges facing the exploitation of the boron/nitrogen hydrides (ammonia-borane), as hydrogen storage material: (1) Development of a simple, efficient, and controllable system for extracting most of the available hydrogen, realizing the high hydrogen density on a system weight/volume basis, and (2) Development of a large-capacity, inexpensive, ammonia-borane regeneration process starting from its decomposition products (BNHx) for recycle. During Phase I of the program both catalytic and non-catalytic decomposition of ammonia borane are being investigated to determine optimum decomposition conditions in terms of temperature for decomposition, rate of hydrogen release, purity of hydrogen produced, thermal efficiency of decomposition, and regenerability of the decomposition products. The non-catalytic studies provide a base-line performance to evaluate catalytic decomposition. Utilization of solid phase catalysts mixed with ammonia-borane was explored for its potential to lower the decomposition temperature, to increase the rate of hydrogen release at a given temperature, to lead to decomposition products

2. Preparation and electrochemical hydrogen storage of boron nitride nanotubes.

PubMed

Chen, X; Gao, X P; Zhang, H; Zhou, Z; Hu, W K; Pan, G L; Zhu, H Y; Yan, T Y; Song, D Y

2005-06-16

Boron nitride (BN) nanotubes were synthesized through chemical vapor deposition over a wafer made by a LaNi5/B mixture and nickel powder at 1473 K. Scanning electron microscopy, transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were performed to characterize the microstructure and composition of BN nanotubes. It was found that the obtained BN nanotubes were straight with a diameter of 30-50 nm and a length of up to several microns. We first verify that the BN nanotubes can storage hydrogen by means of an electrochemical method, though its capacity is low at present. The hydrogen desorption of nonelectrochemical recombination in cyclic voltammograms, which is considered as the slow reaction at BN nanotubes, suggests the possible existence of strong chemisorption of hydrogen, and it may lead to the lower discharge capacity of BN nanotubes. It is tentatively concluded that the improvement of the electrocatalytic activity by surface modification with metal or alloy would enhance the electrochemical hydrogen storage capacity of BN nanotubes.

3. Technical challenges and future direction for high-efficiency metal hydride thermal energy storage systems

Ward, Patrick A.; Corgnale, Claudio; Teprovich, Joseph A.; Motyka, Theodore; Hardy, Bruce; Sheppard, Drew; Buckley, Craig; Zidan, Ragaiy

2016-04-01

Recently, there has been increasing interest in thermal energy storage (TES) systems for concentrated solar power (CSP) plants, which allow for continuous operation when sunlight is unavailable. Thermochemical energy storage materials have the advantage of much higher energy densities than latent or sensible heat materials. Furthermore, thermochemical energy storage systems based on metal hydrides have been gaining great interest for having the advantage of higher energy densities, better reversibility, and high enthalpies. However, in order to achieve higher efficiencies desired of a thermal storage system by the US Department of Energy, the system is required to operate at temperatures >600 °C. Operation at temperatures >600 °C presents challenges including material selection, hydrogen embrittlement and permeation of containment vessels, appropriate selection of heat transfer fluids, and cost. Herein, the technical difficulties and proposed solutions associated with the use of metal hydrides as TES materials in CSP applications are discussed and evaluated.

4. Mechanical ball-milling preparation of fullerene/cobalt core/shell nanocomposites with high electrochemical hydrogen storage ability.

PubMed

Bao, Di; Gao, Peng; Shen, Xiande; Chang, Cheng; Wang, Longqiang; Wang, Ying; Chen, Yujin; Zhou, Xiaoming; Sun, Shuchao; Li, Guobao; Yang, Piaoping

2014-02-26

The design and synthesis of new hydrogen storage nanomaterials with high capacity at low cost is extremely desirable but remains challenging for today's development of hydrogen economy. Because of the special honeycomb structures and excellent physical and chemical characters, fullerenes have been extensively considered as ideal materials for hydrogen storage materials. To take the most advantage of its distinctive symmetrical carbon cage structure, we have uniformly coated C60's surface with metal cobalt in nanoscale to form a core/shell structure through a simple ball-milling process in this work. The X-ray diffraction (XRD), scanning electron microscope (SEM), Raman spectra, high-solution transmission electron microscopy (HRTEM), energy-dispersive X-ray spectrometry (EDX) elemental mappings, and X-ray photoelectron spectroscopy (XPS) measurements have been conducted to evaluate the size and the composition of the composites. In addition, the blue shift of C60 pentagonal pinch mode demonstrates the formation of Co-C chemical bond, and which enhances the stability of the as-obtained nanocomposites. And their electrochemical experimental results demonstrate that the as-obtained C60/Co composites have excellent electrochemical hydrogen storage cycle reversibility and considerably high hydrogen storage capacities of 907 mAh/g (3.32 wt % hydrogen) under room temperature and ambient pressure, which is very close to the theoretical hydrogen storage capacities of individual metal Co (3.33 wt % hydrogen). Furthermore, their hydrogen storage processes and the mechanism have also been investigated, in which the quasi-reversible C60/Co↔C60/Co-Hx reaction is the dominant cycle process.

5. Grand challenges in mass storage: A system integrator's perspective

NASA Technical Reports Server (NTRS)

Mintz, Dan; Lee, Richard

1993-01-01

The grand challenges are the following: to develop more innovation in approach; to expand the I/O barrier; to achieve increased volumetric efficiency and incremental cost improvements; to reinforce the 'weakest link' software; to implement improved architectures; and to minimize the impact of self-destructing technologies. Mass storage is defined as any type of storage system exceeding 100 GBytes in total size, under the control of a centralized file management scheme. The topics covered are presented in viewgraph form.

6. Down Select Report of Chemical Hydrogen Storage Materials, Catalysts, and Spent Fuel Regeneration Processes

SciTech Connect

Ott, Kevin; Linehan, Sue; Lipiecki, Frank; Aardahl, Christopher L.

2008-08-24

The DOE Hydrogen Storage Program is focused on identifying and developing viable hydrogen storage systems for onboard vehicular applications. The program funds exploratory research directed at identifying new materials and concepts for storage of hydrogen having high gravimetric and volumetric capacities that have the potential to meet long term technical targets for onboard storage. Approaches currently being examined are reversible metal hydride storage materials, reversible hydrogen sorption systems, and chemical hydrogen storage systems. The latter approach concerns materials that release hydrogen in endothermic or exothermic chemical bond-breaking processes. To regenerate the spent fuels arising from hydrogen release from such materials, chemical processes must be employed. These chemical regeneration processes are envisioned to occur offboard the vehicle.

7. High-capacity hydrogen storage in lithium and sodium amidoboranes

SciTech Connect

Xiong, Zhitao; Yong, Chaw K.; Wu, Guotao; Chen, Ping; Shaw, Wendy J.; Karkamkar, Abhijeet J.; Autrey, Thomas; Jones, Martin O.; Johnson, Simon; Edwards, Peter; David, Bill

2008-02-21

A substantial effort worldwide has been given to materials development for onboard hydrogen storage over the past decade.1-6 One interesting family of potential hydrogen storage materials are ammonia borane (AB-NH3BH3) and the related amineboranes. Ammonia borane having a H content of 19.6 mass% encounters relatively high kinetic barrier in dehydrogenation. Recently some work has been reported on approaches to lower the ammonia borane dehydrogenation temperature by introducing nanoscaffold, using Ir-based catalysts or ionic liquids.4-6 Some work has focused on modifying the thermodynamics of ‘stable’ hydrides with additives that stabilize the dehydrogenated products.7 We have been thinking about this from the opposite point of view, i. e., altering the chemical composition of ammonia borane through the addition of amides and hydrides in order to destabilize it.8 The rationale behind this is that the inherent polarity and intermolecular interactions (dihydrogen bonding) of ammonia borane can be altered, and result in different dehydrogenation mechanism. In this paper we report that the interaction between LiH and ammonia borane leads to the replacement of a hydrogen by lithium to yield LiNH2BH3 with substantial resultant changes in dehydrogenation behavior. Battelle operates the Pacific Northwest National Laboratory for the US Department of Energy.

8. Activated boron nitride nanotubes: A potential material for room-temperature hydrogen storage

Jhi, Seung-Hoon

2006-10-01

Activated forms of boron nitride nanotubes are studied for potential applications to hydrogen storage with the use of pseudopotential density functional method. The binding and diffusion energies of adsorbed hydrogen are particularly calculated. The calculated binding energy of hydrogen on activated boron nitride nanotubes is found to lie in the right range for room-temperature storage. It is also shown that diffusion through the active sites enables hydrogen to access the inner surface of the nanotubes, which leads to the increase of the storage capacity. Current study provides a tangible solution to increase the operating temperature and capacity of hydrogen storage based on heteropolar nanomaterials such as boron nitride nanotubes.

9. Highly efficient hydrogen storage system based on ammonium bicarbonate/formate redox equilibrium over palladium nanocatalysts.

PubMed

Su, Ji; Yang, Lisha; Lu, Mi; Lin, Hongfei

2015-03-01

A highly efficient, reversible hydrogen storage-evolution process has been developed based on the ammonium bicarbonate/formate redox equilibrium over the same carbon-supported palladium nanocatalyst. This heterogeneously catalyzed hydrogen storage system is comparable to the counterpart homogeneous systems and has shown fast reaction kinetics of both the hydrogenation of ammonium bicarbonate and the dehydrogenation of ammonium formate under mild operating conditions. By adjusting temperature and pressure, the extent of hydrogen storage and evolution can be well controlled in the same catalytic system. Moreover, the hydrogen storage system based on aqueous-phase ammonium formate is advantageous owing to its high volumetric energy density.

10. Glass Bubbles Insulation for Liquid Hydrogen Storage Tanks

Sass, J. P.; Cyr, W. W. St.; Barrett, T. M.; Baumgartner, R. G.; Lott, J. W.; Fesmire, J. E.

2010-04-01

A full-scale field application of glass bubbles insulation has been demonstrated in a 218,000 L liquid hydrogen storage tank. This work is the evolution of extensive materials testing, laboratory scale testing, and system studies leading to the use of glass bubbles insulation as a cost efficient and high performance alternative in cryogenic storage tanks of any size. The tank utilized is part of a rocket propulsion test complex at the NASA Stennis Space Center and is a 1960's vintage spherical double wall tank with an evacuated annulus. The original perlite that was removed from the annulus was in pristine condition and showed no signs of deterioration or compaction. Test results show a significant reduction in liquid hydrogen boiloff when compared to recent baseline data prior to removal of the perlite insulation. The data also validates the previous laboratory scale testing (1000 L) and full-scale numerical modeling (3,200,000 L) of boiloff in spherical cryogenic storage tanks. The performance of the tank will continue to be monitored during operation of the tank over the coming years.

11. Technical and economic assessment of methods for the storage of large quantities of hydrogen

Taylor, J. B.; Alderson, J. E. A.; Kalyanam, K. M.; Phillips, L. A.; Lyle, A. B.

Attention is given to five scenarios for the storage of large quantities of hydrogen, involving storage above ground as a cryogenic liquid as well as high pressure storage both above and below ground in either natural or man-made cavities. The incremental cost of storage is calculated, and sensitivity is determined for variations of throughput, capital cost and electricity cost. These data also include the costs of electrolytic hydrogen and of hydrogen liquefaction. It is established that the cost of storage can add between 30 and 300 percent to the cost of hydrogen; it is accordingly essential that large offsetting benefits exist, in order to achieve economic variablity.

12. 76 FR 4338 - Research and Development Strategies for Compressed & Cryo-Compressed Hydrogen Storage Workshops

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-25

... Laboratory, in conjunction with the Hydrogen Storage team of the EERE Fuel Cell Technologies Program, will be.../hydrogenandfuelcells/wkshp_compressedcryo.html . The purpose of the compressed hydrogen workshop on Monday February... Research and Development Strategies for Compressed & Cryo- Compressed Hydrogen Storage Workshops......

13. Complex Hydride Compounds with Enhanced Hydrogen Storage Capacity

SciTech Connect

Mosher, Daniel A.; Opalka, Susanne M.; Tang, Xia; Laube, Bruce L.; Brown, Ronald J.; Vanderspurt, Thomas H.; Arsenault, Sarah; Wu, Robert; Strickler, Jamie; Anton, Donald L.; Zidan, Ragaiy; Berseth, Polly

2008-02-18

The United Technologies Research Center (UTRC), in collaboration with major partners Albemarle Corporation (Albemarle) and the Savannah River National Laboratory (SRNL), conducted research to discover new hydride materials for the storage of hydrogen having on-board reversibility and a target gravimetric capacity of ≥ 7.5 weight percent (wt %). When integrated into a system with a reasonable efficiency of 60% (mass of hydride / total mass), this target material would produce a system gravimetric capacity of ≥ 4.5 wt %, consistent with the DOE 2007 target. The approach established for the project combined first principles modeling (FPM - UTRC) with multiple synthesis methods: Solid State Processing (SSP - UTRC), Solution Based Processing (SBP - Albemarle) and Molten State Processing (MSP - SRNL). In the search for novel compounds, each of these methods has advantages and disadvantages; by combining them, the potential for success was increased. During the project, UTRC refined its FPM framework which includes ground state (0 Kelvin) structural determinations, elevated temperature thermodynamic predictions and thermodynamic / phase diagram calculations. This modeling was used both to precede synthesis in a virtual search for new compounds and after initial synthesis to examine reaction details and options for modifications including co-reactant additions. The SSP synthesis method involved high energy ball milling which was simple, efficient for small batches and has proven effective for other storage material compositions. The SBP method produced very homogeneous chemical reactions, some of which cannot be performed via solid state routes, and would be the preferred approach for large scale production. The MSP technique is similar to the SSP method, but involves higher temperature and hydrogen pressure conditions to achieve greater species mobility. During the initial phases of the project, the focus was on higher order alanate complexes in the phase space

14. Hydrogen Storage at Ambient Temperature by the Spillover Mechanism

SciTech Connect

Yang , Ralph T.

2011-02-04

The goal of this project was to develop new nanostructured sorbent materials, using the hydrogen spillover mechanism that could meet the DOE 2010 system targets for on-board vehicle hydrogen storage. Hydrogen spillover may be broadly defined as the transport (i.e., via surface diffusion) of dissociated hydrogen adsorbed or formed on a first surface onto another surface. The first surface is typically a metal (that dissociates H2) and the second surface is typically the support on which the metal is doped. Hydrogen spillover is a well documented phenomenon in the catalysis literature, and has been known in the catalysis community for over four decades, although it is still not well understood.1, 2 Much evidence has been shown in the literature on its roles played in catalytic reactions. Very little has been studied on hydrogen storage by spillover at ambient temperature. However, it is also known to occur at such temperature, e.g., direct evidence has been shown for spillover on commercial fuel-cell, highly dispersed Pt/C, Ru/C and PtRu/C catalysts by inelastic neutron scattering.3 To exploit spillover for storage, among the key questions are whether spillover is reversible at ambient temperature and if the adsorption (refill) and desorption rates at ambient temperature are fast enough for automotive applications. In this project, we explored new sorbents by using a transition metal (e.g., Pt, Ru, Pd and Ni) as the H2 dissociation source and sorbents as the hydrogen receptor. The receptors included superactivated carbons (AX-21 and Maxsorb), metal organic frameworks (MOFs) and zeolites. Different metal doping methods have been used successfully to achieve high metal dispersion thereby allowing significant spillover enhancements, as well as a bridging technique used for bridging to MOFs. Among the metals tested, Pt is the hardest to achieve high metal dispersion (and consequently spillover) while Ru is the easiest to disperse. By properly dispersing Pt on

15. Material synthesis and hydrogen storage of palladium-rhodium alloy.

SciTech Connect

Lavernia, Enrique J.; Yang, Nancy Y. C.; Ong, Markus D.

2011-08-01

Pd and Pd alloys are candidate material systems for Tr or H storage. We have actively engaged in material synthesis and studied the material science of hydrogen storage for Pd-Rh alloys. In collaboration with UC Davis, we successfully developed/optimized a supersonic gas atomization system, including its processing parameters, for Pd-Rh-based alloy powders. This optimized system and processing enable us to produce {le} 50-{mu}m powders with suitable metallurgical properties for H-storage R&D. In addition, we studied hydrogen absorption-desorption pressure-composition-temperature (PCT) behavior using these gas-atomized Pd-Rh alloy powders. The study shows that the pressure-composition-temperature (PCT) behavior of Pd-Rh alloys is strongly influenced by its metallurgy. The plateau pressure, slope, and H/metal capacity are highly dependent on alloy composition and its chemical distribution. For the gas-atomized Pd-10 wt% Rh, the absorption plateau pressure is relatively high and consistent. However, the absorption-desorption PCT exhibits a significant hysteresis loop that is not seen from the 30-nm nanopowders produced by chemical precipitation. In addition, we observed that the presence of hydrogen introduces strong lattice strain, plastic deformation, and dislocation networking that lead to material hardening, lattice distortions, and volume expansion. The above observations suggest that the H-induced dislocation networking is responsible for the hysteresis loop seen in the current atomized Pd-10 wt% Rh powders. This conclusion is consistent with the hypothesis suggested by Flanagan and others (Ref 1) that plastic deformation or dislocations control the hysteresis loop.

16. Hydrogen Trailer Storage Facility (Building 878). Consequence analysis

SciTech Connect

Banda, Z.; Wood, C.L.

1994-12-01

The Department of Energy Order 5500.3A requires facility-specific hazards assessments be prepared, maintained, and used for emergency planning purposes. This consequence analysis documents the impact that a hydrogen accident could have to employees, the general public, and nearby facilities. The computer model ARCHIE was utilized to determine discharge rates, toxic vapor dispersion analyses, flammable vapor cloud hazards, explosion hazards, and flame jets for the Hydrogen Trailer Storage Facility located at Building 878. To determine over pressurization effects, hand calculations derived from the Department of the Air Force Manual, Structures to Resist the Effects of Accidental Explosions, were utilized. The greatest distances at which a postulated facility event will produce the Lower Flammability and the Lower Detonation Levels are 1,721 feet and 882 feet, respectively. The greatest distance at which 10.0 psi overpressure (i.e., total building destruction) is reached is 153 feet.

17. Hydrogen Storage in Novel Carbon-Based Nanostructured Materials

SciTech Connect

Whitney, E. S.; Curtis, C. J.; Engtrakul, C.; Davis, M. F.; Su, T.; Parilla, P. A.; Simpson, L. J.; Blackburn, J. L.; Zhao, Y.; Kim, Y.-H.; Zhang, S. B.; Heben, M. J.; Dillon, A. C.

2006-01-01

Experimental wet chemical approaches to complex an iron atom with two C60 fullerenes, representing a new molecule, dubbed a 'bucky dumbbell', have been demonstrated. The structure of this molecule has been determined by 13C solid-state nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR). Furthermore, this structure has been shown to have unique binding sites for dihydrogen molecules with the technique of temperature programmed desorption (TPD). The new adsorption sites have binding energies that are stronger than that observed for hydrogen physisorbed on planar graphite, but significantly weaker than a chemical C-H bond. Further development of these molecules could make them ideal candidates for onboard vehicular hydrogen storage.

18. Destabilized and catalyzed borohydride for reversible hydrogen storage

DOEpatents

Mohtadi, Rana F.; Zidan, Ragaiy; Gray, Joshua; Stowe, Ashley C.; Sivasubramanian, Premkumar

2012-02-28

A process of forming a hydrogen storage material, including the steps of: providing a borohydride material of the formula: M(BH.sub.4).sub.x where M is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing an alanate material of the formula: M.sub.1(AlH.sub.4).sub.x where M.sub.1 is an alkali metal or an alkaline earth metal and 1.ltoreq.x.ltoreq.2; providing a halide material of the formula: M.sub.2Hal.sub.x where M.sub.2 is an alkali metal, an alkaline earth metal or transition metal and Hal is a halide and 1.ltoreq.x.ltoreq.4; combining the borohydride, alanate and halide materials such that 5 to 50 molar percent from the borohydride material is present forming a reaction product material having a lower hydrogen release temperature than the alanate material.

19. Enhancement of Hydrogen Storage Capacity in Hydrate Lattices

SciTech Connect

Yoo, Soohaeng; Xantheas, Sotiris S.

2012-02-16

First principles electronic structure calculations of the gas phase pentagonal dodecahedron (H2O)20 (D-cage) and tetrakaidecahedron (H2O)24 (T-cage), which are building blocks of structure I (sI) hydrate lattice, suggest that these can accommodate up to a maximum of 5 and 7 guest hydrogen molecules, respectively. For the pure hydrogen hydrate, Born-Oppenheimer Molecular Dynamics (BOMD) simulations of periodic (sI) hydrate lattices indicate that the guest molecules are released into the vapor phase via the hexagonal phases of the larger T-cages. An additional mechanism for the migration between neighboring D- and T-cages was found to occur through a shared pentagonal face via the breaking and reforming of a hydrogen bond. This molecular mechanism is also found for the expulsion of a CH4 molecule from the D-cage. The presence of methane in the larger T-cages was found to block this release, therefore suggesting possible scenarios for the stabilization of these mixed guest clathrate hydrates and the potential enhancement of their hydrogen storage capacity.

20. EMR modelling of a hydrogen-based electrical energy storage

Agbli, K. S.; Hissel, D.; Péra, M.-C.; Doumbia, I.

2011-05-01

This paper deals with multi-physics modelling of the stationary system. This modelling is the first step to reach the fuel cell system dimensioning aim pursued. Besides this modelling approach based on the stationary energetic system, the novelty in this paper is both the new approach of the photovoltaic EMR modelling and the EMR of the hydrogen storage process. The granular modelling approach is used to model each component of the system. Considering a stand alone PEM fuel cell system, hydrogen is expected to be produced and stored on the spot from renewable energy (photovoltaic) in order to satisfy the fuel availability. In fact, to develop a generic and modular model, energetic macroscopic representation (EMR) is used as graphical modelling tool. Allowing to be easily grasped by the experts even not necessarily gotten used to the modelling formalism, EMR is helpful to model the multi-domains energetic chain. The solar energy through solar module is converted in electrical energy; part of this energy is transformed in chemical energy (hydrogen) thanks to an electrolyser. Then the hydrogen is compressed into a tank across a storage system. The latter part of the solar module energy is stored as electrical energy within supercapacitor or lead-acid battery. Using the modularity feature of the EMR, the whole system is modelled entity by entity; afterwards by putting them together the overall system has been reconstructed. According to the scale effect of the system entities, some simulation and/or experimental results are given. Given to the different aims which are pursued in the sustainable energy framework like prediction, control and optimisation, EMR modelling approach is a reliable option for the energy management in real time of energetic system in macroscopic point of view.

1. Some recent efforts in chemical hydrogen storage at Loa Alamos

SciTech Connect

Gordon, John C; Davis, Benjamin L; Burrell, Anthony K; Nakagawa, Tessui; Ott, Kevin C; Smythe, Nathan C; Sutton, Andrew D; Henson, Neil J; Baker, R. Thomas; Hamilton, Charles W; Dixon, David A; Garner Ill, Edward B; Vasiliu, Monica

2010-12-08

Within the transportation sector, a necessity towards realizing the use of hydrogen (H{sub 2}) as an alternative fuel, is its storage for controlled delivery. The U.S. DOE's Centers of Excellence (CoE) in H{sub 2} storage have pursued different methodologies (metal hydrides, chemical hydrides, and sorbents), for the express purpose of supplanting gasoline's current > 300 mile driving range. Chemical H{sub 2} storage has been dominated by one material, ammonia borane (H3B-NH3, AB), due to its high gravimetric capacity of H{sub 2} (19.6 wt %) and low molecular weight (30.7 g mol{sup -1} ). As such, a number of publications have described H{sub 2} release from amine boranes, yielding various rates depending on the method applied. The viability of any storage system is also dependent on efficient recyclability. Within our CoE we have thus endeavored to find efficient base-metal catalyzed AB dehydrogenation pathways and regeneration schemes for the spent fuel from H{sub 2} depleted AB. We will present some recent results in these areas in this vein.

2. Hydrogen-Bromine Flow Battery: Hydrogen Bromine Flow Batteries for Grid Scale Energy Storage

SciTech Connect

2010-10-01

GRIDS Project: LBNL is designing a flow battery for grid storage that relies on a hydrogen-bromine chemistry which could be more efficient, last longer and cost less than today’s lead-acid batteries. Flow batteries are fundamentally different from traditional lead-acid batteries because the chemical reactants that provide their energy are stored in external tanks instead of inside the battery. A flow battery can provide more energy because all that is required to increase its storage capacity is to increase the size of the external tanks. The hydrogen-bromine reactants used by LBNL in its flow battery are inexpensive, long lasting, and provide power quickly. The cost of the design could be well below $100 per kilowatt hour, which would rival conventional grid-scale battery technologies. 3. The Sustainable Hydrogen Economy: Addressing the Challenges Ahead NASA Astrophysics Data System (ADS) Turner, John A. 2006-10-01 It is rapidly becoming apparent that energy is one of the most important issues facing our world today; in fact, in today's society energy is as important as food and water. Humankind finds itself faced the challenge of how to continue to power society, particularly in the face of the rapidly growing economies of emerging nations like India and China, and yet answer questions of sustainability, energy security, geopolitics and global environment. One of the major issues facing America and most other countries in the world is how to supply a transportation fuel, an energy carrier to replace gasoline. Hydrogen as an energy carrier, primarily derived from water, can address issues of sustainability, environmental emissions and energy security. The Hydrogen Economy'' then is the production of hydrogen, its distribution and utilization as an energy carrier. While the vision of a hydrogen economy has been around for over 130 years, the most recent push to use hydrogen as an energy carrier came as part of a US Presidential Initiative, announced in the 2003 State of the Union Address. It is important that we consider hydrogen in tandem with other technologies as an alternative to the once-abundant hydrocarbon resources on which our society depends. This talk will introduce sustainable energy systems, including fuel cell technology and discuss the vision, the barriers and possible pathways for the production and implementation of hydrogen into the energy infrastructure. 4. Low-Cost Precursors to Novel Hydrogen Storage Materials SciTech Connect Suzanne W. Linehan; Arthur A. Chin; Nathan T. Allen; Robert Butterick; Nathan T. Kendall; I. Leo Klawiter; Francis J. Lipiecki; Dean M. Millar; David C. Molzahn; Samuel J. November; Puja Jain; Sara Nadeau; Scott Mancroni 2010-12-31 From 2005 to 2010, The Dow Chemical Company (formerly Rohm and Haas Company) was a member of the Department of Energy Center of Excellence on Chemical Hydrogen Storage, which conducted research to identify and develop chemical hydrogen storage materials having the potential to achieve DOE performance targets established for on-board vehicular application. In collaboration with Center co-leads Los Alamos National Laboratory (LANL) and Pacific Northwest National Laboratory (PNNL), and other Center partners, Dow's efforts were directed towards defining and evaluating novel chemistries for producing chemical hydrides and processes for spent fuel regeneration. In Phase 1 of this project, emphasis was placed on sodium borohydride (NaBH{sub 4}), long considered a strong candidate for hydrogen storage because of its high hydrogen storage capacity, well characterized hydrogen release chemistry, safety, and functionality. Various chemical pathways for regenerating NaBH{sub 4} from spent sodium borate solution were investigated, with the objective of meeting the 2010/2015 DOE targets of$2-3/gal gasoline equivalent at the pump ($2-3/kg H{sub 2}) for on-board hydrogen storage systems and an overall 60% energy efficiency. With the September 2007 No-Go decision for NaBH{sub 4} as an on-board hydrogen storage medium, focus was shifted to ammonia borane (AB) for on-board hydrogen storage and delivery. However, NaBH{sub 4} is a key building block to most boron-based fuels, and the ability to produce NaBH{sub 4} in an energy-efficient, cost-effective, and environmentally sound manner is critical to the viability of AB, as well as many leading materials under consideration by the Metal Hydride Center of Excellence. Therefore, in Phase 2, research continued towards identifying and developing a single low-cost NaBH4 synthetic route for cost-efficient AB first fill, and conducting baseline cost estimates for first fill and regenerated AB using a variety of synthetic routes. This project 5. Tailoring Thermodynamics and Kinetics for Hydrogen Storage in Complex Hydrides towards Applications. PubMed Liu, Yongfeng; Yang, Yaxiong; Gao, Mingxia; Pan, Hongge 2016-02-01 Solid-state hydrogen storage using various materials is expected to provide the ultimate solution for safe and efficient on-board storage. Complex hydrides have attracted increasing attention over the past two decades due to their high gravimetric and volumetric hydrogen densities. In this account, we review studies from our lab on tailoring the thermodynamics and kinetics for hydrogen storage in complex hydrides, including metal alanates, borohydrides and amides. By changing the material composition and structure, developing feasible preparation methods, doping high-performance catalysts, optimizing multifunctional additives, creating nanostructures and understanding the interaction mechanisms with hydrogen, the operating temperatures for hydrogen storage in metal amides, alanates and borohydrides are remarkably reduced. This temperature reduction is associated with enhanced reaction kinetics and improved reversibility. The examples discussed in this review are expected to provide new inspiration for the development of complex hydrides with high hydrogen capacity and appropriate thermodynamics and kinetics for hydrogen storage. 6. Chemical Hydride Slurry for Hydrogen Production and Storage SciTech Connect McClaine, Andrew W 2008-09-30 The purpose of this project was to investigate and evaluate the attractiveness of using a magnesium chemical hydride slurry as a hydrogen storage, delivery, and production medium for automobiles. To fully evaluate the potential for magnesium hydride slurry to act as a carrier of hydrogen, potential slurry compositions, potential hydrogen release techniques, and the processes (and their costs) that will be used to recycle the byproducts back to a high hydrogen content slurry were evaluated. A 75% MgH2 slurry was demonstrated, which was just short of the 76% goal. This slurry is pumpable and storable for months at a time at room temperature and pressure conditions and it has the consistency of paint. Two techniques were demonstrated for reacting the slurry with water to release hydrogen. The first technique was a continuous mixing process that was tested for several hours at a time and demonstrated operation without external heat addition. Further work will be required to reduce this design to a reliable, robust system. The second technique was a semi-continuous process. It was demonstrated on a 2 kWh scale. This system operated continuously and reliably for hours at a time, including starts and stops. This process could be readily reduced to practice for commercial applications. The processes and costs associated with recycling the byproducts of the water/slurry reaction were also evaluated. This included recovering and recycling the oils of the slurry, reforming the magnesium hydroxide and magnesium oxide byproduct to magnesium metal, hydriding the magnesium metal with hydrogen to form magnesium hydride, and preparing the slurry. We found that the SOM process, under development by Boston University, offers the lowest cost alternative for producing and recycling the slurry. Using the H2A framework, a total cost of production, delivery, and distribution of$4.50/kg of hydrogen delivered or $4.50/gge was determined. Experiments performed at Boston 7. Predicted energy densitites for nickel-hydrogen and silver-hydrogen cells embodying metallic hydrides for hydrogen storage NASA Technical Reports Server (NTRS) Easter, R. W. 1974-01-01 Simplified design concepts were used to estimate gravimetric and volumetric energy densities for metal hydrogen battery cells for assessing the characteristics of cells containing metal hydrides as compared to gaseous storage cells, and for comparing nickel cathode and silver cathode systems. The silver cathode was found to yield superior energy densities in all cases considered. The inclusion of hydride forming materials yields cells with very high volumetric energy densities that also retain gravimetric energy densities nearly as high as those of gaseous storage cells. 8. Analysis of Hydrogen and Competing Technologies for Utility-Scale Energy Storage (Presentation) SciTech Connect Steward, D. 2010-02-11 Presentation about the National Renewable Energy Laboratory's analysis of hydrogen energy storage scenarios, including analysis framework, levelized cost comparison of hydrogen and competing technologies, analysis results, and conclusions drawn from the analysis. 9. Hydrogen storage in Pd nanocrystals covered with a metal-organic framework NASA Astrophysics Data System (ADS) Li, Guangqin; Kobayashi, Hirokazu; Taylor, Jared M.; Ikeda, Ryuichi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki; Yamamoto, Tomokazu; Toh, Shoichi; Matsumura, Syo; Kitagawa, Hiroshi 2014-08-01 Hydrogen is an essential component in many industrial processes. As a result of the recent increase in the development of shale gas, steam reforming of shale gas has received considerable attention as a major source of H2, and the more efficient use of hydrogen is strongly demanded. Palladium is well known as a hydrogen-storage metal and an effective catalyst for reactions related to hydrogen in a variety of industrial processes. Here, we present remarkably enhanced capacity and speed of hydrogen storage in Pd nanocrystals covered with the metal-organic framework (MOF) HKUST-1 (copper(II) 1,3,5-benzenetricarboxylate). The Pd nanocrystals covered with the MOF have twice the storage capacity of the bare Pd nanocrystals. The significantly enhanced hydrogen storage capacity was confirmed by hydrogen pressure-composition isotherms and solid-state deuterium nuclear magnetic resonance measurements. The speed of hydrogen absorption in the Pd nanocrystals is also enhanced by the MOF coating. 10. Hydrogen storage material and process using graphite additive with metal-doped complex hydrides DOEpatents Zidan, Ragaiy; Ritter, James A.; Ebner, Armin D.; Wang, Jun; Holland, Charles E. 2008-06-10 A hydrogen storage material having improved hydrogen absorbtion and desorption kinetics is provided by adding graphite to a complex hydride such as a metal-doped alanate, i.e., NaAlH.sub.4. The incorporation of graphite into the complex hydride significantly enhances the rate of hydrogen absorbtion and desorption and lowers the desorption temperature needed to release stored hydrogen. 11. Hydrogen Storage in Nano-Phase Diamond at High Temperature and Its Release SciTech Connect Tushar K Ghosh 2008-10-13 The objectives of this proposed research were: 91) Separation and storage of hydrogen on nanophase diamonds. It is expected that the produced hydrogen, which will be in a mixture, can be directed to a nanophase diamond system directly, which will not only store the hydrogen, but also separate it from the gas mixture, and (2) release of the stored hydrogen from the nanophase diamond. 12. Theoretical Study of Hydrogen Storage in Ca-Coated Fullerenes. PubMed Wang, Qian; Sun, Qiang; Jena, Puru; Kawazoe, Yoshiyuki 2009-02-10 First principles calculations based on gradient corrected density functional theory and molecular dynamics simulations of Ca decorated fullerene yield some novel results: (1) C60 fullerene decorated with 32 Ca atoms on each of its 20 hexagonal and 12 pentagonal faces is extremely stable. Unlike transition metal atoms that tend to cluster on a fullerene surface, Ca atoms remain isolated even at high temperatures. (2) C60Ca32 can absorb up to 62 H2 molecules in two layers. The first 30 H2 molecules dissociate and bind atomically on the 60 triangular faces of the fullerene with an average binding energy of 0.45 eV/H, while the remaining 32 H2 molecules bind on the second layer quasi-molecularly with an average binding energy of 0.11 eV/H2. These binding energies are ideal for Ca coated C60 to operate as a hydrogen storage material at near ambient temperatures with fast kinetics. (3) The gravimetric density of this hydrogen storage material can reach 6.2 wt %. Simple model calculations show that this density is the limiting value for higher fullerenes. 13. Reversible Hydrogen Storage Materials – Structure, Chemistry, and Electronic Structure SciTech Connect Robertson, Ian M.; Johnson, Duane D. 2014-06-21 To understand the processes involved in the uptake and release of hydrogen from candidate light-weight metal hydride storage systems, a combination of materials characterization techniques and first principle calculation methods have been employed. In addition to conventional microstructural characterization in the transmission electron microscope, which provides projected information about the through thickness microstructure, electron tomography methods were employed to determine the three-dimensional spatial distribution of catalyst species for select systems both before and after dehydrogenation. Catalyst species identification as well as compositional analysis of the storage material before and after hydrogen charging and discharging was performed using a combination of energy dispersive spectroscopy, EDS, and electron energy loss spectroscopy, EELS. The characterization effort was coupled with first-principles, electronic-structure and thermodynamic techniques to predict and assess meta-stable and stable phases, reaction pathways, and thermodynamic and kinetic barriers. Systems studied included:NaAlH4, CaH2/CaB6 and Ca(BH4)2, MgH2/MgB2, Ni-Catalyzed Magnesium Hydride, TiH2-Catalyzed Magnesium Hydride, LiBH4, Aluminum-based systems and Aluminum 14. Pd supported ordered mesoporous hollow carbon spheres (OMHCS) for hydrogen storage NASA Astrophysics Data System (ADS) Zielinska, Beata; Michalkiewicz, Beata; Chen, Xuecheng; Mijowska, Ewa; Kalenczuk, Ryszard J. 2016-03-01 Two synthesis methods (reflux and impregnation) have been compared for the preparation of Pd supported OMHCS. The hydrogen storage properties of OMHCS and OMHCS@Pd were studied. OMHCS@Pd samples exhibited enhanced hydrogen storage capacity in respect to the pristine OMHCS. The significant differences between the hydrogen storage capacities of OMHCS@Pd produced via reflux and impregnation routes were observed. It was found that among OMHCS@Pd samples, the one with higher surface area and broader Pd particle distribution showed the highest hydrogen sorption properties. The results indicated that reflux doping method is more appropriate for the preparation of OMHCS@Pd with high hydrogen capacity. 15. Prediction of hydrogen storage on Y-decorated graphene: A density functional theory study NASA Astrophysics Data System (ADS) Liu, Wenbo; Liu, Yang; Wang, Rongguo 2014-03-01 Yttrium decorated graphene has been investigated as a potential carrier for high density hydrogen storage. The adsorption energy and optimized geometry for yttrium on pristine and boron doped graphene have been studied by DFT calculations. The clustering and stability of isolated yttrium atoms on graphene has also been considered. For yttrium decorated boron doped graphene, each yttrium can attach six hydrogen molecules with average adsorption energy of -0.568 eV per hydrogen molecule and the hydrogen storage capacity of this material is 5.78 wt.%, indicating yttrium decorated boron doped graphene as a promising hydrogen storage candidate. 16. Davisson-Germer Prize Talk: Hydrogen storage in nanoporous materials NASA Astrophysics Data System (ADS) Chabal, Yves 2009-03-01 To develop a hydrogen-based energy technology, several classes of materials are being considered to achieve the DOE targets for gravimetric and volumetric hydrogen densities for hydrogen storage, including liquids (e.g. ammonium borohydrides), clathrate structures, complex metal hydrides, nanostructured (e.g. carbon) an nanoporous materials. Fundamental studies are necessary to determine the ultimate hydrogen capacity of each system. Nanoporous Metal-organic Framework (MOF) materials are promising candidates for hydrogen storage because the chemical nature and size of their unit cell can be tailored to weakly attract and incorporate H2 molecules, with good volumetric and mass density. In this talk, we consider the structure M2(BDC)2(TED), where M is a metal atom (Zn, Ni, Cu), BDC is benzenedicarboxylate and TED triethylenediamine, to determine the location and interaction of H2 molecules within the MOF. These compounds are isostructural and crystallize in the tetragonal phase (space group P4/ncc), they construct 3D porous structures with relatively large pore size (˜7-8 A ), pore volume (˜0.63-0.84 cc/g) and BET surface area (˜1500-1900 m^2/g). At high pressures (300-800 psi), the perturbation of the H-H stretching mode can be measured with IR absorption spectroscopy, showing a 35 cm-1 redshift from the unperturbed ortho (4155 cm-1 ) and para (4161 cm-1 ) frequencies. Using a newly developed non empirical van der Waals DFT method vdW-DFT),ootnotetextJ.Y. Lee, D.H. Olson, L. Pan, T.J. Emge, J. Li, Adv. Func. Mater. 17, 1255 (2007) it can be shown that the locus of the deepest H2 binding positions lies within to types of narrow channels. The energies of the most stable binding sites, as well as the number of such binding sites, are consistent with the values obtained from experimental adsorption isotherms, and heat of adsorption) data.ootnotetextM. Dion, H. Ryberg, E. Schroder, D. C. Langreth, B.I. Lundqvist, Phys. Rev. Lett. 92, 246401 (2004). Importantly, the 17. Method and system for hydrogen evolution and storage DOEpatents Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M. 2012-12-11 A method and system for storing and evolving hydrogen (H.sub.2) employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel. 18. Method and System for Hydrogen Evolution and Storage DOEpatents Thorn, David L.; Tumas, William; Hay, P. Jeffrey; Schwarz, Daniel E.; Cameron, Thomas M. 2008-10-21 A method and system for storing and evolving hydrogen employ chemical compounds that can be hydrogenated to store hydrogen and dehydrogenated to evolve hydrogen. A catalyst lowers the energy required for storing and evolving hydrogen. The method and system can provide hydrogen for devices that consume hydrogen as fuel. 19. Storage and production of hydrogen for fuel cell applications NASA Astrophysics Data System (ADS) Aiello, Rita The increased utilization of proton-exchange membrane (PEM) fuel cells as an alternative to internal combustion engines is expected to increase the demand for hydrogen, which is used as the energy source in these systems. The objective of this work is to develop and test new methods for the storage and production of hydrogen for fuel cells. Six ligand-stabilized hydrides were synthesized and tested as hydrogen storage media for use in portable fuel cells. These novel compounds are more stable than classical hydrides (e.g., NaBH4, LiAlH4) and react to release hydrogen less exothermically upon hydrolysis with water. Three of the compounds produced hydrogen in high yield (88 to 100 percent of the theoretical) and at significantly lower temperatures than those required for the hydrolysis of NaBH4 and LiAlH4. However, a large excess of water and acid were required to completely wet the hydride and keep the pH of the reaction medium neutral. The hydrolysis of the classical hydrides with steam can overcome these limitations. This reaction was studied in a flow reactor and the results indicate that classical hydrides can be hydrolyzed with steam in high yields at low temperatures (110 to 123°C) and in the absence of acid. Although excess steam was required, the pH of the condensed steam was neutral. Consequently, steam could be recycled back to the reactor. Production of hydrogen for large-scale transportation fuel cells is primarily achieved via the steam reforming, partial oxidation or autothermal reforming of natural gas or the steam reforming of methanol. However, in all of these processes CO is a by-product that must be subsequently removed because the Pt-based electrocatalyst used in the fuel cells is poisoned by its presence. The direct cracking of methane over a Ni/SiO2 catalyst can produce CO-free hydrogen. In addition to hydrogen, filamentous carbon is also produced. This material accumulates on the catalyst and eventually deactivates it. The Ni/SiO2 catalyst 20. Systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies DOEpatents Fliermans; , Carl B. 2012-08-07 Some or all of the needs above can be addressed by embodiments of the invention. According to embodiments of the invention, systems and methods for facilitating hydrogen storage using naturally occurring nanostructure assemblies can be implemented. In one embodiment, a method for storing hydrogen can be provided. The method can include providing diatoms comprising diatomaceous earth or diatoms from a predefined culture. In addition, the method can include heating the diatoms in a sealed environment in the presence of at least one of titanium, a transition metal, or a noble metal to provide a porous hydrogen storage medium. Furthermore, the method can include exposing the porous hydrogen storage medium to hydrogen. In addition, the method can include storing at least a portion of the hydrogen in the porous hydrogen storage medium. 1. Mg-based nanocomposites with high capacity and fast kinetics for hydrogen storage. PubMed Yao, Xiangdong; Wu, Chengzhang; Du, Aijun; Lu, Gao Qing; Cheng, Huiming; Smith, Sean C; Zou, Jin; He, Yinghe 2006-06-22 Magnesium and its alloys have shown a great potential in effective hydrogen storage due to their advantages of high volumetric/gravimetric hydrogen storage capacity and low cost. However, the use of these materials in fuel cells for automotive applications at the present time is limited by high hydrogenation temperature and sluggish sorption kinetics. This paper presents the recent results of design and development of magnesium-based nanocomposites demonstrating the catalytic effects of carbon nanotubes and transition metals on hydrogen adsorption in these materials. The results are promising for the application of magnesium materials for hydrogen storage, with significantly reduced absorption temperatures and enhanced ab/desorption kinetics. High level Density Functional Theory calculations support the analysis of the hydrogenation mechanisms by revealing the detailed atomic and molecular interactions that underpin the catalytic roles of incorporated carbon and titanium, providing clear guidance for further design and development of such materials with better hydrogen storage properties. 2. Shape-dependent hydrogen-storage properties in Pd nanocrystals: which does hydrogen prefer, octahedron (111) or cube (100)? PubMed Li, Guangqin; Kobayashi, Hirokazu; Dekura, Shun; Ikeda, Ryuichi; Kubota, Yoshiki; Kato, Kenichi; Takata, Masaki; Yamamoto, Tomokazu; Matsumura, Syo; Kitagawa, Hiroshi 2014-07-23 Pd octahedrons and cubes enclosed by {111} and {100} facets, respectively, have been synthesized for investigation of the shape effect on hydrogen-absorption properties. Hydrogen-storage properties were investigated using in situ powder X-ray diffraction, in situ solid-state (2)H NMR and hydrogen pressure-composition isotherm measurements. With these measurements, it was found that the exposed facets do not affect hydrogen-storage capacity; however, they significantly affect the absorption speed, with octahedral nanocrystals showing the faster response. The heat of adsorption of hydrogen and the hydrogen diffusion pathway were suggested to be dominant factors for hydrogen-absorption speed. Furthermore, in situ solid-state (2)H NMR detected for the first time the state of (2)H in a solid-solution (Pd + H) phase of Pd nanocrystals at rt. PMID:25019951 3. Frontiers, Opportunities and Challenges for a Hydrogen Economy NASA Astrophysics Data System (ADS) Turner, John 2015-03-01 Energy carriers are the staple for powering the society we live in. Coal, oil, natural gas, gasoline and diesel all carry energy in chemical bonds, used in almost all areas of our civilization. But these carriers have a limited-use lifetime on this planet. They are finite, contribute to climate change and carry significant geopolitical issues. If mankind is to maintain and grow our societies, new energy carriers must be developed and deployed into our energy infrastructure. Hydrogen is the simplest of all the energy carriers and when refined from water using renewable energies like solar and wind, represents a sustainable energy carrier, viable for millennia to come. This talk with discuss the challenges for sustainable production of hydrogen, along with the promise and possible pathways for implementing hydrogen into our energy infrastructure. 4. Storage of Renewable Energy by Reduction of CO2 with Hydrogen. PubMed Züttel, Andreas; Mauron, Philippe; Kato, Shunsuke; Callini, Elsa; Holzer, Marco; Huang, Jianmei 2015-01-01 The main difference between the past energy economy during the industrialization period which was mainly based on mining of fossil fuels, e.g. coal, oil and methane and the future energy economy based on renewable energy is the requirement for storage of the energy fluxes. Renewable energy, except biomass, appears in time- and location-dependent energy fluxes as heat or electricity upon conversion. Storage and transport of energy requires a high energy density and has to be realized in a closed materials cycle. The hydrogen cycle, i.e. production of hydrogen from water by renewable energy, storage and use of hydrogen in fuel cells, combustion engines or turbines, is a closed cycle. However, the hydrogen density in a storage system is limited to 20 mass% and 150 kg/m(3) which limits the energy density to about half of the energy density in fossil fuels. Introducing CO(2) into the cycle and storing hydrogen by the reduction of CO(2) to hydrocarbons allows renewable energy to be converted into synthetic fuels with the same energy density as fossil fuels. The resulting cycle is a closed cycle (CO(2) neutral) if CO(2) is extracted from the atmosphere. Today's technology allows CO(2) to be reduced either by the Sabatier reaction to methane, by the reversed water gas shift reaction to CO and further reduction of CO by the Fischer-Tropsch synthesis (FTS) to hydrocarbons or over methanol to gasoline. The overall process can only be realized on a very large scale, because the large number of by-products of FTS requires the use of a refinery. Therefore, a well-controlled reaction to a specific product is required for the efficient conversion of renewable energy (electricity) into an easy to store liquid hydrocarbon (fuel). In order to realize a closed hydrocarbon cycle the two major challenges are to extract CO(2) from the atmosphere close to the thermodynamic limit and to reduce CO(2) with hydrogen in a controlled reaction to a specific hydrocarbon. Nanomaterials with 5. Storage of Renewable Energy by Reduction of CO2 with Hydrogen. PubMed Züttel, Andreas; Mauron, Philippe; Kato, Shunsuke; Callini, Elsa; Holzer, Marco; Huang, Jianmei 2015-01-01 The main difference between the past energy economy during the industrialization period which was mainly based on mining of fossil fuels, e.g. coal, oil and methane and the future energy economy based on renewable energy is the requirement for storage of the energy fluxes. Renewable energy, except biomass, appears in time- and location-dependent energy fluxes as heat or electricity upon conversion. Storage and transport of energy requires a high energy density and has to be realized in a closed materials cycle. The hydrogen cycle, i.e. production of hydrogen from water by renewable energy, storage and use of hydrogen in fuel cells, combustion engines or turbines, is a closed cycle. However, the hydrogen density in a storage system is limited to 20 mass% and 150 kg/m(3) which limits the energy density to about half of the energy density in fossil fuels. Introducing CO(2) into the cycle and storing hydrogen by the reduction of CO(2) to hydrocarbons allows renewable energy to be converted into synthetic fuels with the same energy density as fossil fuels. The resulting cycle is a closed cycle (CO(2) neutral) if CO(2) is extracted from the atmosphere. Today's technology allows CO(2) to be reduced either by the Sabatier reaction to methane, by the reversed water gas shift reaction to CO and further reduction of CO by the Fischer-Tropsch synthesis (FTS) to hydrocarbons or over methanol to gasoline. The overall process can only be realized on a very large scale, because the large number of by-products of FTS requires the use of a refinery. Therefore, a well-controlled reaction to a specific product is required for the efficient conversion of renewable energy (electricity) into an easy to store liquid hydrocarbon (fuel). In order to realize a closed hydrocarbon cycle the two major challenges are to extract CO(2) from the atmosphere close to the thermodynamic limit and to reduce CO(2) with hydrogen in a controlled reaction to a specific hydrocarbon. Nanomaterials with 6. Self-Printing on Graphitic Nanosheets with Metal Borohydride Nanodots for Hydrogen Storage NASA Astrophysics Data System (ADS) Li, Yongtao; Ding, Xiaoli; Zhang, Qingan 2016-08-01 Although the synthesis of borohydride nanostructures is sufficiently established for advancement of hydrogen storage, obtaining ultrasmall (sub-10 nm) metal borohydride nanocrystals with excellent dispersibility is extremely challenging because of their high surface energy, exceedingly strong reducibility/hydrophilicity and complicated composition. Here, we demonstrate a mechanical-force-driven self-printing process that enables monodispersed (~6 nm) NaBH4 nanodots to uniformly anchor onto freshly-exfoliated graphitic nanosheets (GNs). Both mechanical-forces and borohydride interaction with GNs stimulate NaBH4 clusters intercalation/absorption into the graphite interlayers acting as a ‘pen’ for writing, which is accomplished by exfoliating GNs with the ‘printed’ borohydrides. These nano-NaBH4@GNs exhibit favorable thermodynamics (decrease in ∆H of ~45%), rapid kinetics (a greater than six-fold increase) and stable de-/re-hydrogenation that retains a high capacity (up to ~5 wt% for NaBH4) compared with those of micro-NaBH4. Our results are helpful in the scalable fabrication of zero-dimensional complex hydrides on two-dimensional supports with enhanced hydrogen storage for potential applications. 7. Self-Printing on Graphitic Nanosheets with Metal Borohydride Nanodots for Hydrogen Storage. PubMed Li, Yongtao; Ding, Xiaoli; Zhang, Qingan 2016-08-03 Although the synthesis of borohydride nanostructures is sufficiently established for advancement of hydrogen storage, obtaining ultrasmall (sub-10 nm) metal borohydride nanocrystals with excellent dispersibility is extremely challenging because of their high surface energy, exceedingly strong reducibility/hydrophilicity and complicated composition. Here, we demonstrate a mechanical-force-driven self-printing process that enables monodispersed (~6 nm) NaBH4 nanodots to uniformly anchor onto freshly-exfoliated graphitic nanosheets (GNs). Both mechanical-forces and borohydride interaction with GNs stimulate NaBH4 clusters intercalation/absorption into the graphite interlayers acting as a 'pen' for writing, which is accomplished by exfoliating GNs with the 'printed' borohydrides. These nano-NaBH4@GNs exhibit favorable thermodynamics (decrease in ∆H of ~45%), rapid kinetics (a greater than six-fold increase) and stable de-/re-hydrogenation that retains a high capacity (up to ~5 wt% for NaBH4) compared with those of micro-NaBH4. Our results are helpful in the scalable fabrication of zero-dimensional complex hydrides on two-dimensional supports with enhanced hydrogen storage for potential applications. 8. Self-Printing on Graphitic Nanosheets with Metal Borohydride Nanodots for Hydrogen Storage PubMed Central Li, Yongtao; Ding, Xiaoli; Zhang, Qingan 2016-01-01 Although the synthesis of borohydride nanostructures is sufficiently established for advancement of hydrogen storage, obtaining ultrasmall (sub-10 nm) metal borohydride nanocrystals with excellent dispersibility is extremely challenging because of their high surface energy, exceedingly strong reducibility/hydrophilicity and complicated composition. Here, we demonstrate a mechanical-force-driven self-printing process that enables monodispersed (~6 nm) NaBH4 nanodots to uniformly anchor onto freshly-exfoliated graphitic nanosheets (GNs). Both mechanical-forces and borohydride interaction with GNs stimulate NaBH4 clusters intercalation/absorption into the graphite interlayers acting as a ‘pen’ for writing, which is accomplished by exfoliating GNs with the ‘printed’ borohydrides. These nano-NaBH4@GNs exhibit favorable thermodynamics (decrease in ∆H of ~45%), rapid kinetics (a greater than six-fold increase) and stable de-/re-hydrogenation that retains a high capacity (up to ~5 wt% for NaBH4) compared with those of micro-NaBH4. Our results are helpful in the scalable fabrication of zero-dimensional complex hydrides on two-dimensional supports with enhanced hydrogen storage for potential applications. PMID:27484735 9. Self-Printing on Graphitic Nanosheets with Metal Borohydride Nanodots for Hydrogen Storage. PubMed Li, Yongtao; Ding, Xiaoli; Zhang, Qingan 2016-01-01 Although the synthesis of borohydride nanostructures is sufficiently established for advancement of hydrogen storage, obtaining ultrasmall (sub-10 nm) metal borohydride nanocrystals with excellent dispersibility is extremely challenging because of their high surface energy, exceedingly strong reducibility/hydrophilicity and complicated composition. Here, we demonstrate a mechanical-force-driven self-printing process that enables monodispersed (~6 nm) NaBH4 nanodots to uniformly anchor onto freshly-exfoliated graphitic nanosheets (GNs). Both mechanical-forces and borohydride interaction with GNs stimulate NaBH4 clusters intercalation/absorption into the graphite interlayers acting as a 'pen' for writing, which is accomplished by exfoliating GNs with the 'printed' borohydrides. These nano-NaBH4@GNs exhibit favorable thermodynamics (decrease in ∆H of ~45%), rapid kinetics (a greater than six-fold increase) and stable de-/re-hydrogenation that retains a high capacity (up to ~5 wt% for NaBH4) compared with those of micro-NaBH4. Our results are helpful in the scalable fabrication of zero-dimensional complex hydrides on two-dimensional supports with enhanced hydrogen storage for potential applications. PMID:27484735 10. Hydrogen Energy Storage: Grid and Transportation Services (Technical Report) SciTech Connect Not Available 2015-02-01 Proceedings of an expert workshop convened by the U.S. Department of Energy and Industry Canada, and hosted by the National Renewable Energy Laboratory and the California Air Resources Board, May 14-15, 2014, in Sacramento, California, to address the topic of hydrogen energy storage (HES). HES systems provide multiple opportunities to increase the resilience and improve the economics of energy sup supply systems underlying the electric grid, gas pipeline systems, and transportation fuels. This is especially the case when considering particular social goals and market drivers, such as reducing carbon emissions, increasing reliability of supply, and reducing consumption of conventional petroleum fuels. This report compiles feedback collected during the workshop, which focused on policy and regulatory issues related to HES systems. Report sections include an introduction to HES pathways, market demand, and the "smart gas" concept; an overview of the workshop structure; and summary results from panel presentations and breakout groups. 11. Uranium for hydrogen storage applications : a materials science perspective. SciTech Connect Shugard, Andrew D.; Tewell, Craig R.; Cowgill, Donald F.; Kolasinski, Robert D. 2010-08-01 Under appropriate conditions, uranium will form a hydride phase when exposed to molecular hydrogen. This makes it quite valuable for a variety of applications within the nuclear industry, particularly as a storage medium for tritium. However, some aspects of the U+H system have been characterized much less extensively than other common metal hydrides (particularly Pd+H), likely due to radiological concerns associated with handling. To assess the present understanding, we review the existing literature database for the uranium hydride system in this report and identify gaps in the existing knowledge. Four major areas are emphasized: {sup 3}He release from uranium tritides, the effects of surface contamination on H uptake, the kinetics of the hydride phase formation, and the thermal desorption properties. Our review of these areas is then used to outline potential avenues of future research. 12. Modular Energy Storage System for Hydrogen Fuel Cell Vehicles SciTech Connect Thomas, Janice 2010-08-27 The objective of the project is to develop technologies, specifically power electronics, energy storage electronics and controls that provide efficient and effective energy management between electrically powered devices in alternative energy vehicles plug-in electric vehicles, hybrid vehicles, range extended vehicles, and hydrogen-based fuel cell vehicles. The in-depth research into the complex interactions between the lower and higher voltage systems from data obtained via modeling, bench testing and instrumented vehicle data will allow an optimum system to be developed from a performance, cost, weight and size perspective. The subsystems are designed for modularity so that they may be used with different propulsion and energy delivery systems. This approach will allow expansion into new alternative energy vehicle markets. 13. Technical Assessment of Compressed Hydrogen Storage Tank Systems for Automotive Applications SciTech Connect Hua, Thanh; Ahluwalia, Rajesh; Peng, J. -K; Kromer, Matt; Lasher, Stephen; McKenney, Kurtis; Law, Karen; Sinha, Jayanti 2010-09-01 This technical report describes DOE's assessment of the performance and cost of compressed hydrogen storage tank systems for automotive applications. The on-board performance (by Argonne National Lab) and high-volume manufacturing cost (by TIAX LLC) were estimated for compressed hydrogen storage tanks. The results were compared to DOE's 2010, 2015, and ultimate full fleet hydrogen storage targets. The Well-to-Tank (WTT) efficiency as well as the off-board performance and cost of delivering compressed hydrogen were also documented in the report. 14. Overview of Two Hydrogen Energy Storage Studies: Wind Hydrogen in California and Blending in Natural Gas Pipelines (Presentation) SciTech Connect Melaina, M. W. 2013-05-01 This presentation provides an overview of two NREL energy storage studies: Wind Hydrogen in California: Case Study and Blending Hydrogen Into Natural Gas Pipeline Networks: A Review of Key Issues. The presentation summarizes key issues, major model input assumptions, and results. 15. Safety Standard for Hydrogen and Hydrogen Systems: Guidelines for Hydrogen System Design, Materials Selection, Operations, Storage and Transportation. Revision NASA Technical Reports Server (NTRS) 1997-01-01 The NASA Safety Standard, which establishes a uniform process for hydrogen system design, materials selection, operation, storage, and transportation, is presented. The guidelines include suggestions for safely storing, handling, and using hydrogen in gaseous (GH2), liquid (LH2), or slush (SLH2) form whether used as a propellant or non-propellant. The handbook contains 9 chapters detailing properties and hazards, facility design, design of components, materials compatibility, detection, and transportation. Chapter 10 serves as a reference and the appendices contained therein include: assessment examples; scaling laws, explosions, blast effects, and fragmentation; codes, standards, and NASA directives; and relief devices along with a list of tables and figures, abbreviations, a glossary and an index for ease of use. The intent of the handbook is to provide enough information that it can be used alone, but at the same time, reference data sources that can provide much more detail if required. 16. Promising gaseous and electrochemical hydrogen storage properties of porous Mg-Pd films under mild conditions. PubMed Xin, Gongbiao; Yuan, Huiping; Jiang, Lijun; Wang, Shumao; Liu, Xiaopeng; Li, Xingguo 2015-05-28 In this paper, the gaseous and electrochemical hydrogen storage properties of 200 nm Mg-Pd thin films with different morphologies have been investigated. The results show that Mg-Pd films become porous with the increase of substrate temperature. Porous Mg-Pd films exhibit superior gaseous and electrochemical hydrogen storage behaviors under mild conditions, including rapid hydrogen sorption kinetics, a large hydrogen storage amount, high electrochemical discharge capacity, and a fast hydrogen diffusion rate. The excellent behaviors of porous Mg-Pd films might be ascribed to the significantly shortened hydrogen diffusion paths and the large contact areas between the hydrogen gas and the solid Mg phases, which are elucidative for the development and applications of thick Mg-Pd films. 17. Chemical bridges for enhancing hydrogen storage by spillover and methods for forming the same DOEpatents Yang, Ralph T.; Li, Yingwei; Qi, Gongshin; Lachawiec, Jr., Anthony J. 2012-12-25 A composition for hydrogen storage includes a source of hydrogen atoms, a receptor, and a chemical bridge formed between the source and the receptor. The chemical bridge is formed from a precursor material. The receptor is adapted to receive hydrogen spillover from the source. 18. Thermodynamic Properties of Organometallic Dihydrogen Complexes for Hydrogen Storage Applications NASA Astrophysics Data System (ADS) Abrecht, David Gregory appropriate ranges for hydrogen storage applications. Simulated thermodynamic values for Fe complexes were found to significantly underestimate experimental behavior, demonstrating the importance of the magnetic spin state of the molecule to hydrogen binding properties. 19. Making the case for direct hydrogen storage in fuel cell vehicles SciTech Connect James, B.D.; Thomas, C.E.; Baum, G.N.; Lomas, F.D. Jr.; Kuhn, I.F. Jr. 1997-12-31 Three obstacles to the introduction of direct hydrogen fuel cell vehicles are often states: (1) inadequate onboard hydrogen storage leading to limited vehicle range; (2) lack of an hydrogen infrastructure, and (3) cost of the entire fuel cell system. This paper will address the first point with analysis of the problem/proposed solutions for the remaining two obstacles addressed in other papers. Results of a recent study conducted by Directed Technologies Inc. will be briefly presented. The study, as part of Ford Motor Company/DOE PEM Fuel Cell Program, examines multiple pure hydrogen onboard storage systems on the basis of weight, volume, cost, and complexity. Compressed gas, liquid, carbon adsorption, and metal hydride storage are all examined with compressed hydrogen storage at 5,000 psia being judged the lowest-risk, highest benefit, near-term option. These results are combined with recent fuel cell vehicle drive cycle simulations to estimate the onboard hydrogen storage requirement for full vehicle range (380 miles on the combined Federal driving schedule). The results indicate that a PNGV-like vehicle using powertrain weights and performance realistically available by the 2004 PNGV target data can achieve approximate fuel economy equivalent to 100 mpg on gasoline (100 mpg{sub eq}) and requires storage of approximately 3.6 kg hydrogen for full vehicle storage quantity allows 5,000 psia onboard storage without altering the vehicle exterior lines or appreciably encroaching on the passenger or trunk compartments. 20. Hydrogen Energy Storage (HES) and Power-to-Gas Economic Analysis; NREL (National Renewable Energy Laboratory) SciTech Connect Eichman, Joshua 2015-07-30 This presentation summarizes opportunities for hydrogen energy storage and power-to-gas and presents the results of a market analysis performed by the National Renewable Energy Laboratory to quantify the value of energy storage. Hydrogen energy storage and power-to-gas systems have the ability to integrate multiple energy sectors including electricity, transportation, and industrial. On account of the flexibility of hydrogen systems, there are a variety of potential system configurations. Each configuration will provide different value to the owner, customers and grid system operator. This presentation provides an economic comparison of hydrogen storage, power-to-gas and conventional storage systems. The total cost is compared to the revenue with participation in a variety of markets to assess the economic competitiveness. It is found that the sale of hydrogen for transportation or industrial use greatly increases competitiveness. Electrolyzers operating as demand response devices (i.e., selling hydrogen and grid services) are economically competitive, while hydrogen storage that inputs electricity and outputs only electricity have an unfavorable business case. Additionally, tighter integration with the grid provides greater revenue (e.g., energy, ancillary service and capacity markets are explored). Lastly, additional hours of storage capacity is not necessarily more competitive in current energy and ancillary service markets and electricity markets will require new mechanisms to appropriately compensate long duration storage devices. 1. Final Report: Main Group Element Chemistry in Service of Hydrogen Storage and Activation SciTech Connect David A. Dixon; Anthony J. Arduengo, III 2010-09-30 Replacing combustion of carbon-based fuels with alternative energy sources that have minimal environmental impact is one of the grand scientific and technological challenges of the early 21st century. Not only is it critical to capture energy from new, renewable sources, it is also necessary to store the captured energy efficiently and effectively for use at the point of service when and where it is needed, which may not be collocated with the collection site. There are many potential storage media but we focus on the storage of energy in chemical bonds. It is more efficient to store energy on a per weight basis in chemical bonds. This is because it is hard to pack electrons into small volumes with low weight without the use of chemical bonds. The focus of the project was the development of new chemistries to enable DOE to meet its technical objectives for hydrogen storage using chemical hydrogen storage systems. We provided computational chemistry support in terms of thermodynamics, kinetics, and properties prediction in support of the experimental efforts of the DOE Center of Excellence for Chemical Hydrogen Storage. The goal of the Center is to store energy in chemical bonds involving hydrogen atoms. Once the hydrogen is stored in a set of X-H/Y-H bonds, the hydrogen has to be easily released and the depleted fuel regenerated very efficiently. This differs substantially from our current use of fossil fuel energy sources where the reactant is converted to energy plus CO2 (coal) or CO2 and H2O (gasoline, natural gas), which are released into the atmosphere. In future energy storage scenarios, the spent fuel will be captured and the energy storage medium regenerated. This places substantial additional constraints on the chemistry. The goal of the computational chemistry work was to reduce the time to design new materials and develop materials that meet the 2010 and 2015 DOE objectives in terms of weight percent, volume, release time, and regeneration ability. This 2. Carbon Capture and Storage (CCS): Overview, Developments, and Challenges NASA Astrophysics Data System (ADS) Busch, Andreas; Amann, Alexandra; Kronimus, Alexander; Kühn, Michael 2010-05-01 largest piece of cake is referring to R&D projects on a small-scale demonstration basis. Numerous further demonstration or small-scale commercial projects have been announced for the near future. Such developments demonstrate that there are no major technological barriers to widespread geological CO2 storage. Main challenges are rather on the public acceptance, legislation and commercial site. Commercially CCS costs are mainly dominated by the high costs of CO2 capture where, depending on the capture method, CO2 needs to be separated from the emission gas stream produced during energy production. Policy, legislation and regulatory framework issues are further hurdles that need to be considered for large scale implementation of this technology. Finally public acceptance of this technology will likely affect the large-scale implementation of CO2 geological storage. 3. Epidemiology and diagnosis of lysosomal storage disorders; challenges of screening. PubMed Kingma, Sandra D K; Bodamer, Olaf A; Wijburg, Frits A 2015-03-01 The lysosomal storage disorders (LSDs) are a group of genetic disorders resulting from defective lysosomal metabolism and subsequent accumulation of substrates. Patients present with a large phenotypic spectrum of disease manifestations that are generally not specific for LSDs, leading to considerable diagnostic delay and missed cases. Introduction of new disease modifying therapies for LSDs has made early diagnosis a priority. Increased awareness, but particularly the introduction of screening programs allow for early diagnosis and timely initiation of treatment. This review will provide insight into the epidemiology and diagnostic process for LSDs. In addition, challenges for carrier screening, high-risk screening and newborn population screening for LSDs are discussed. PMID:25987169 4. Hydrogen Storage Materials for Mobile and Stationary Applications: Current State of the Art. PubMed Lai, Qiwen; Paskevicius, Mark; Sheppard, Drew A; Buckley, Craig E; Thornton, Aaron W; Hill, Matthew R; Gu, Qinfen; Mao, Jianfeng; Huang, Zhenguo; Liu, Hua Kun; Guo, Zaiping; Banerjee, Amitava; Chakraborty, Sudip; Ahuja, Rajeev; Aguey-Zinsou, Kondo-Francois 2015-09-01 One of the limitations to the widespread use of hydrogen as an energy carrier is its storage in a safe and compact form. Herein, recent developments in effective high-capacity hydrogen storage materials are reviewed, with a special emphasis on light compounds, including those based on organic porous structures, boron, nitrogen, and aluminum. These elements and their related compounds hold the promise of high, reversible, and practical hydrogen storage capacity for mobile applications, including vehicles and portable power equipment, but also for the large scale and distributed storage of energy for stationary applications. Current understanding of the fundamental principles that govern the interaction of hydrogen with these light compounds is summarized, as well as basic strategies to meet practical targets of hydrogen uptake and release. The limitation of these strategies and current understanding is also discussed and new directions proposed. 5. Demonstration of a micro-fabricated hydrogen storage module for micro-power systems. PubMed Shan, Xi; Payer, Joe H; Wainright, Jesse S; Dudik, Laurie 2011-01-15 The objective of this work was to demonstrate a micro-fabricated hydrogen storage module for micro-power systems. Hydrogen storage materials were developed as thin-film inks to be compatible with an integrated manufacturing process. Performance and durability of storage modules were evaluated. Further, applications were demonstrated for a nickel-hydrogen battery and a micro-fabricated hydrogen-air PEM fuel cell. The ink making process, in which polymer binders and solvents were added to the palladium-treated alloys, slightly decreased the storage capacities, but had little effect on the activation properties of the treated alloys. After 5000 absorption/desorption cycles under hydrogen, the hydrogen storage capacities of the thin-film inks remained high. Absorption/desorption behavior of the ink was tested in the environment of a new type nickel-hydrogen battery, in which it would in contact with 26wt% KOH solution, and the ink showed no apparent degradation. Storage modules were used as the successfully as hydrogen source for PEM fuel cell. 6. Hexagonal boron nitride nanoparticles decorated halloysite clay nanotubes as a potential hydrogen storage medium NASA Astrophysics Data System (ADS) Muthu, R. Naresh; Rajashabala, S.; Kannan, R. 2016-05-01 The light weight and compact hydrogen storage materials is still prerequisite for the carbon free hydrogen fuel cell technology. In this work, the hydrogen storage performance of acid treated halloysite clay nanotubes (A-HNTs) and hexagonal boron nitride (h-BN) nanoparticles decorated acid treated halloysite nanoclay composite (A-HNT-h-BN) are demonstrated, where facile ultrasonic technique is adopted for the synthesis of A-HNT-h-BN nanoclay composite. Hydrogen storage studies were carried out using Sieverts-like hydrogenation setup. The A-HNTs and A-HNT-h-BN nanoclay composite were analyzed by XRD, FTIR, HRTEM, EDX, CHNS-elemental analysis and TGA. The A-HNT-h-BN nanoclay composite shows superior storage capacity of 2.19 wt% at 50 °C compared to the A-HNTs (0.58 wt%). A 100% desorption of stored hydrogen is noted in the temperature range of 138-175 °C. The average binding energy of hydrogen was found to be 0.34 eV for the prepared A-HNT-h-BN nanoclay composite. The excellent storage capability of A-HNT-h-BN nanoclay composite towards hydrogen at ambient temperature may find bright perspective in hydrogen fuel cell technology in near future. 7. Modeling of an Integrated Renewable Energy System (IRES) with hydrogen storage NASA Astrophysics Data System (ADS) Shenoy, Navin Kodange 2010-12-01 Scope and Method of Study. The purpose of the study was to consider the integration of hydrogen storage technology as means of energy storage with renewable sources of energy. Hydrogen storage technology consists of an alkaline electrolyzer, gas storage tank and a fuel cell. The Integrated Renewable Energy System (IRES) under consideration includes wind energy, solar energy from photovoltaics, solar thermal energy and biomass energy in the form of biogas. Energy needs are categorized depending on the type and quality of the energy requirements. After meeting all the energy needs, any excess energy available from wind and PVs is converted into hydrogen using an electrolyzer for later use in a fuel cell. Similarly, when renewable energy generation is not able to supply the actual load demand, the stored hydrogen is utilized through fuel cell to fulfill load demand. Analysis of how IRES operates in order to satisfy different types of energy needs is discussed. Findings and Conclusions. All simulations are performed using MATLAB software. Hydrogen storage technology consisting of an electrolyzer, gas storage tank and a fuel cell is incorporated in the IRES design process for a hypothetical remote community. Results show that whenever renewable energy generated is greater than the electrical demand, excess energy is stored in the form of hydrogen and in case of energy shortfall, the stored hydrogen is utilized through the fuel cell to supply to excess power demand. The overall operation of IRES is enhanced as a result of energy storage in the form of hydrogen. Hydrogen has immense potential to be the energy carrier of the future because of its clean character and the model of hydrogen storage discussed here can form an integral part of IRES for remote area applications. 8. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor PubMed Central Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin 2012-01-01 Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO2/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H2 generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g−1 at 0.5 A g−1 and 287 F g−1 at 1 A g−1 are obtained with TiO2/Ni(OH)2 nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application. PMID:23248745 9. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor. PubMed Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin 2012-01-01 Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO(2)/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H(2) generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g(-1) at 0.5 A g(-1) and 287 F g(-1) at 1 A g(-1) are obtained with TiO(2)/Ni(OH)(2) nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application. 10. Diagnosis of a Poorly Performing Liquid Hydrogen Bulk Storage Sphere NASA Technical Reports Server (NTRS) Krenn, Angela G. 2011-01-01 There are two 850,000 gallon Liquid Hydrogen (LH2) storage spheres used to support the Space Shuttle Program; one residing at Launch Pad A and the other at Launch Pad B. The LH2 Sphere at Pad B has had a high boiloff rate since being brought into service in the 1960's. The daily commodity loss was estimated to be approximately double that of the Pad A sphere, and well above the minimum required by the sphere's specification. Additionally, after being re-painted in the late 1990's a "cold spot" appeared on the outer sphere which resulted in a poor paint bond, and mold formation. Thermography was used to characterize the area, and the boiloff rate was continually evaluated. All evidence suggested that the high boiloff rate was caused by an excessive heat leak into the inner sphere due to an insulation void in the annulus. Pad B was recently taken out of Space Shuttle program service which provided a unique opportunity to diagnose the sphere's poor performance. The sphere was drained and inerted, and then opened from the annular relief device on the top where a series of boroscoping operations were accomplished. Boroscoping revealed a large Perlite insulation void in the region of the sphere where the cold spot was apparent. Perlite was then trucked in and off-loaded into the annular void region until the annulus was full. The sphere has not yet been brought back into service. 11. Integrated photoelectrochemical energy storage: solar hydrogen generation and supercapacitor NASA Astrophysics Data System (ADS) Xia, Xinhui; Luo, Jingshan; Zeng, Zhiyuan; Guan, Cao; Zhang, Yongqi; Tu, Jiangping; Zhang, Hua; Fan, Hong Jin 2012-12-01 Current solar energy harvest and storage are so far realized by independent technologies (such as solar cell and batteries), by which only a fraction of solar energy is utilized. It is highly desirable to improve the utilization efficiency of solar energy. Here, we construct an integrated photoelectrochemical device with simultaneous supercapacitor and hydrogen evolution functions based on TiO2/transition metal hydroxides/oxides core/shell nanorod arrays. The feasibility of solar-driven pseudocapacitance is clearly demonstrated, and the charge/discharge is indicated by reversible color changes (photochromism). In such an integrated device, the photogenerated electrons are utilized for H2 generation and holes for pseudocapacitive charging, so that both the reductive and oxidative energies are captured and converted. Specific capacitances of 482 F g-1 at 0.5 A g-1 and 287 F g-1 at 1 A g-1 are obtained with TiO2/Ni(OH)2 nanorod arrays. This study provides a new research strategy for integrated pseudocapacitor and solar energy application. 12. Diagnosis of a poorly performing liquid hydrogen bulk storage sphere NASA Astrophysics Data System (ADS) Krenn, Angela Gray 2012-06-01 There are two 3,218 cubic meter (850,000 gallon) Liquid Hydrogen (LH2) storage spheres used to support the Space Shuttle Program; one residing at Launch Pad A, the other at Launch Pad B. The Sphere at Pad B had a high boiloff rate when brought into service in the 1960s. In 2001, the daily commodity loss was approximately double that of the Pad A sphere, and well above the maximum allowed by the specification. After being re-painted in the 1990s a "cold spot" appeared on the outer sphere that resulted in poor paint bonding and mold formation. Thermography was used to characterize the area, and the boiloff rate was continually evaluated. All evidence suggested that the high boiloff rate was caused by an excessive heat leak into the inner sphere due to an insulation void in the annulus. Pad B was recently taken out of service, which provided a unique opportunity to perform a series of visual inspections of the insulation. Boroscope examinations revealed a large Perlite void in the region where the cold spot was apparent. Perlite was then trucked in and offloaded into the annular void region until full. The sphere has not yet been brought back into service. 13. Treatment of lysosomal storage disorders: successes and challenges. PubMed Hollak, Carla E M; Wijburg, Frits A 2014-07-01 Treatment options for a number of lysosomal storage disorders have rapidly expanded and currently include enzyme replacement therapy, substrate reduction, chaperone treatment, hematopoietic stem cell transplantation, and gene-therapy. Combination treatments are also explored. Most therapies are not curative but change the phenotypic expression of the disease. The effectiveness of treatment varies considerably between the different diseases, but also between sub-groups of patients with a specific lysosomal storage disorder. The heterogeneity of the patient populations complicates the prediction of benefits of therapy, specifically in patients with milder disease manifestations. In addition, there is a lack of data on the natural history of diseases and disease phenotypes. Initial trial data show benefits on relevant short-term endpoints, but the real world situation may reveal different outcomes. Collaborative international studies are much needed to study the long-term clinical efficacy of treatments, and to detect new complications or associated conditions of the diseases. This review summarizes the available treatment modalities for lysosomal storage disorders and the challenges associated with long term clinical care for these patients. PMID:24820227 14. Strain effects on hydrogen storage capability of metal-decorated graphene: A first-principles study NASA Astrophysics Data System (ADS) Zhou, Miao; Lu, Yunhao; Zhang, Chun; Feng, Yuan Ping 2010-09-01 We report an investigation on strain-engineered adsorption of metal atoms on graphene and hydrogen storage capabilities of metal-decorated graphene by using first-principles approach based on density functional theory. We show that an applied strain not only stabilizes the supported metal atoms and prevents them from clustering but further increases the hydrogen storage capacity. Specifically, a tensile strain of 10% in graphene increases the adsorption energy of Li (Ti) atom by around 75% (71%) and the gravimetric density of hydrogen storage up to 15.4 wt % (9.5 wt %), with a binding energy of ˜0.2 eV/H2. 15. Storage of hydrogen at 303 K in graphite slitlike pores from grand canonical Monte Carlo simulation. PubMed Kowalczyk, Piotr; Tanaka, Hideki; Hołyst, Robert; Kaneko, Katsumi; Ohmori, Takumi; Miyamoto, Junichi 2005-09-15 Grand canonical Monte Carlo (GCMC) simulations were used for the modeling of the hydrogen adsorption in idealized graphite slitlike pores. In all simulations, quantum effects were included through the Feynman and Hibbs second-order effective potential. The simulated surface excess isotherms of hydrogen were used for the determination of the total hydrogen storage, density of hydrogen in graphite slitlike pores, distribution of pore sizes and volumes, enthalpy of adsorption per mole, total surface area, total pore volume, and average pore size of pitch-based activated carbon fibers. Combining experimental results with simulations reveals that the density of hydrogen in graphite slitlike pores at 303 K does not exceed 0.014 g/cm(3), that is, 21% of the liquid-hydrogen density at the triple point. The optimal pore size for the storage of hydrogen at 303 K in the considered pore geometry depends on the pressure of storage. For lower storage pressures, p < 30MPa, the optimal pore width is equal to a 2.2 collision diameter of hydrogen (i.e., 0.65 nm), whereas, for p congruent with 50MPa, the pore width is equal to an approximately 7.2 collision diameter of hydrogen (i.e., 2.13 nm). For the wider pores, that is, the pore width exceeds a 7.2 collision diameter of hydrogen, the surface excess of hydrogen adsorption is constant. The importance of quantum effects is recognized in narrow graphite slitlike pores in the whole range of the hydrogen pressure as well as in wider ones at high pressures of bulk hydrogen. The enthalpies of adsorption per mole for the considered carbonaceous materials are practically constant with hydrogen loading and vary within the narrow range q(st) congruent with 7.28-7.85 kJ/mol. Our systematic study of hydrogen adsorption at 303 K in graphite slitlike pores gives deep insight into the timely problem of hydrogen storage as the most promising source of clean energy. The calculated maximum storage of hydrogen is equal to approximately 1.4 wt 16. Hydrogen transmission/storage with a metal hydride/organic slurry SciTech Connect Breault, R.W.; Rolfe, J.; McClaine, A. 1998-08-01 Thermo Power Corporation has developed a new approach for the production, transmission, and storage of hydrogen. In this approach, a chemical hydride slurry is used as the hydrogen carrier and storage media. The slurry protects the hydride from unanticipated contact with moisture in the air and makes the hydride pumpable. At the point of storage and use, a chemical hydride/water reaction is used to produce high-purity hydrogen. An essential feature of this approach is the recovery and recycle of the spent hydride at centralized processing plants, resulting in an overall low cost for hydrogen. This approach has two clear benefits: it greatly improves energy transmission and storage characteristics of hydrogen as a fuel, and it produces the hydrogen carrier efficiently and economically from a low cost carbon source. The preliminary economic analysis of the process indicates that hydrogen can be produced for$3.85 per million Btu based on a carbon cost of $1.42 per million Btu and a plant sized to serve a million cars per day. This compares to current costs of approximately$9.00 per million Btu to produce hydrogen from $3.00 per million Btu natural gas, and$25 per million Btu to produce hydrogen by electrolysis from $0.05 per Kwh electricity. The present standard for production of hydrogen from renewable energy is photovoltaic-electrolysis at$100 to 150 per million Btu. 17. Hydrogen as a fuel for today and tomorrow: expectations for advanced hydrogen storage materials/systems research. PubMed Hirose, Katsuhiko 2011-01-01 History shows that the evolution of vehicles is promoted by several environmental restraints very similar to the evolution of life. The latest environmental strain is sustainability. Transport vehicles are now facing again the need to advance to use sustainable fuels such as hydrogen. Hydrogen fuel cell vehicles are being prepared for commercialization in 2015. Despite intensive research by the world's scientists and engineers and recent advances in our understanding of hydrogen behavior in materials, the only engineering phase technology which will be available for 2015 is high pressure storage. Thus industry has decided to implement the high pressure tank storage system. However the necessity of smart hydrogen storage is not decreasing but rather increasing because high market penetration of hydrogen fuel cell vehicles is expected from around 2025 onward. In order to bring more vehicles onto the market, cheaper and more compact hydrogen storage is inevitable. The year 2025 seems a long way away but considering the field tests and large scale preparation required, there is little time available for research. Finding smart materials within the next 5 years is very important to the success of fuel cells towards a low carbon sustainable world. 18. New insights into designing metallacarborane based room temperature hydrogen storage media SciTech Connect Bora, Pankaj Lochan; Singh, Abhishek K. 2013-10-28 Metallacarboranes are promising towards realizing room temperature hydrogen storage media because of the presence of both transition metal and carbon atoms. In metallacarborane clusters, the transition metal adsorbs hydrogen molecules and carbon can link these clusters to form metal organic framework, which can serve as a complete storage medium. Using first principles density functional calculations, we chalk out the underlying principles of designing an efficient metallacarborane based hydrogen storage media. The storage capacity of hydrogen depends upon the number of available transition metal d-orbitals, number of carbons, and dopant atoms in the cluster. These factors control the amount of charge transfer from metal to the cluster, thereby affecting the number of adsorbed hydrogen molecules. This correlation between the charge transfer and storage capacity is general in nature, and can be applied to designing efficient hydrogen storage systems. Following this strategy, a search for the best metallacarborane was carried out in which Sc based monocarborane was found to be the most promising H{sub 2} sorbent material with a 9 wt.% of reversible storage at ambient pressure and temperature. 19. New insights into designing metallacarborane based room temperature hydrogen storage media. PubMed Bora, Pankaj Lochan; Singh, Abhishek K 2013-10-28 Metallacarboranes are promising towards realizing room temperature hydrogen storage media because of the presence of both transition metal and carbon atoms. In metallacarborane clusters, the transition metal adsorbs hydrogen molecules and carbon can link these clusters to form metal organic framework, which can serve as a complete storage medium. Using first principles density functional calculations, we chalk out the underlying principles of designing an efficient metallacarborane based hydrogen storage media. The storage capacity of hydrogen depends upon the number of available transition metal d-orbitals, number of carbons, and dopant atoms in the cluster. These factors control the amount of charge transfer from metal to the cluster, thereby affecting the number of adsorbed hydrogen molecules. This correlation between the charge transfer and storage capacity is general in nature, and can be applied to designing efficient hydrogen storage systems. Following this strategy, a search for the best metallacarborane was carried out in which Sc based monocarborane was found to be the most promising H2 sorbent material with a 9 wt.% of reversible storage at ambient pressure and temperature. 20. High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides SciTech Connect Daniel A. Mosher; Xia Tang; Ronald J. Brown; Sarah Arsenault; Salvatore Saitta; Bruce L. Laube; Robert H. Dold; Donald L. Anton 2007-07-27 This final report describes the motivations, activities and results of the hydrogen storage independent project "High Density Hydrogen Storage System Demonstration Using NaAlH4 Based Complex Compound Hydrides" performed by the United Technologies Research Center under the Department of Energy Hydrogen Program, contract # DE-FC36-02AL67610. The objectives of the project were to identify and address the key systems technologies associated with applying complex hydride materials, particularly ones which differ from those for conventional metal hydride based storage. This involved the design, fabrication and testing of two prototype systems based on the hydrogen storage material NaAlH4. Safety testing, catalysis studies, heat exchanger optimization, reaction kinetics modeling, thermochemical finite element analysis, powder densification development and material neutralization were elements included in the effort. 1. Hydrogen storage as a hydride. Citations from the International Aerospace Abstracts data base NASA Technical Reports Server (NTRS) Zollars, G. F. 1980-01-01 These citations from the international literature concern the storage of hydrogen in various metal hydrides. Binary and intermetallic hydrides are considered. Specific alloys discussed are iron titanium, lanthanium nickel, magnesium copper and magnesium nickel among others. 2. New Carbon-Based Porous Materials with Increased Heats of Adsorption for Hydrogen Storage SciTech Connect Snurr, Randall Q.; Hupp, Joseph T.; Kanatzidis, Mercouri G.; Nguyen, SonBinh T. 2014-11-03 Hydrogen fuel cell vehicles are a promising alternative to internal combustion engines that burn gasoline. A significant challenge in developing fuel cell vehicles is to store enough hydrogen on-board to allow the same driving range as current vehicles. One option for storing hydrogen on vehicles is to use tanks filled with porous materials that act as “sponges” to take up large quantities of hydrogen without the need for extremely high pressures. The materials must meet many requirements to make this possible. This project aimed to develop two related classes of porous materials to meet these requirements. All materials were synthesized from molecular constituents in a building-block approach, which allows for the creation of an incredibly wide variety of materials in a tailorable fashion. The materials have extremely high surface areas, to provide many locations for hydrogen to adsorb. In addition, they were designed to contain cations that create large electric fields to bind hydrogen strongly but not too strongly. Molecular modeling played a key role as a guide to experiment throughout the project. A major accomplishment of the project was the development of a material with record hydrogen uptake at cryogenic temperatures. Although the ultimate goal was materials that adsorb large quantities of hydrogen at room temperature, this achievement at cryogenic temperatures is an important step in the right direction. In addition, there is significant interest in applications at these temperatures. The hydrogen uptake, measured independently at NREL was 8.0 wt %. This is, to the best of our knowledge, the highest validated excess hydrogen uptake reported to date at 77 K. This material was originally sketched on paper based on a hypothesis that extended framework struts would yield materials with excellent hydrogen storage properties. However, before starting the synthesis, we used molecular modeling to assess the performance of the material for hydrogen uptake 3. First principles DFT investigation of yttrium-doped graphene: Electronic structure and hydrogen storage SciTech Connect Desnavi, Sameerah; Chakraborty, Brahmananda; Ramaniah, Lavanya M. 2014-04-24 The electronic structure and hydrogen storage capability of Yttrium-doped grapheme has been theoretically investigated using first principles density functional theory (DFT). Yttrium atom prefers the hollow site of the hexagonal ring with a binding energy of 1.40 eV. Doping by Y makes the system metallic and magnetic with a magnetic moment of 2.11 μ{sub B}. Y decorated graphene can adsorb up to four hydrogen molecules with an average binding energy of 0.415 eV. All the hydrogen atoms are physisorbed with an average desorption temperature of 530.44 K. The Y atoms can be placed only in alternate hexagons, which imply a wt% of 6.17, close to the DoE criterion for hydrogen storage materials. Thus, this system is potential hydrogen storage medium with 100% recycling capability. 4. Hydrogen storage in Ti-TiO2 multilayers NASA Astrophysics Data System (ADS) Tarnawski, Z.; Kim-Ngan, Nhu-T. H.; Zakrzewska, K.; Drogowska, K.; Brudnik, A.; Balogh, A. G.; Kužel, R.; Havela, L.; Sechovsky, V. 2013-06-01 Multilayered thin films of Ti-TiO2 system have been investigated, focusing on all of the important parameters in both photocatalysis and H storage. Numerous Ti-TiO2 thin films with a single-, bi- and tri-layered structure have been deposited on different substrates by means of dc pulsed magnetron sputtering from a metallic Ti target in an inert Ar or reactive Ar + O2 atmosphere. The film chemical composition, depth profile, layer thickness and structure were determined by combined analysis of x-ray diffraction, x-ray reflectometry, Rutherford back- scattering and optical reflectivity spectra. The results show that the Ti films deposited on Si(111) exhibit a strong preferred orientation with the (00.1) plane parallel to the substrate, while a columnar structure was developed for TiO2 films. H charging at 1 bar and at 300 °C revealed that, in the case of the tri-layered structure of Ti/TiO2/Ti/Si(111), H diffused through the TiO2 layer without any accumulation in it. Pd acts as a catalyst for gathering H in Ti layers and up to 50% of H is stored in the topmost and bottom Ti layers. The preferential orientation in the Ti films was found to be destroyed upon hydrogenation at 100 bar. The hydride TiHx phase (x < 0.66) was formed under such a high H pressure. Invited talk at the 6th International Workshop on Advanced Materials Science and Nanotechnology IWAMSN2012, 30 October - 2 November, 2012, Ha Long, Vietnam. 5. Passive ZBO storage of liquid hydrogen and liquid oxygen applied to space science mission concepts NASA Astrophysics Data System (ADS) Plachta, D. W.; Christie, R. J.; Jurns, J. M.; Kittel, P. 2006-02-01 Liquid hydrogen and oxygen cryogenic propulsion and storage were recently considered for application to Titan Explorer and Comet Nuclear Sample Return space science mission investigations. These missions would require up to 11 years of cryogenic storage. We modeled and designed cryogenic propellant storage concepts for these missions. By isolating the propellant tank’s view to deep space, we were able to achieve zero boil-off for both liquid hydrogen and oxygen propellant storage without cryocoolers. Several shades were incorporated to protect the tanks from the sun and spacecraft bus, and to protect the hydrogen tank from the warmer oxygen tank. This had a dramatic effect on the surface temperatures of the propellant tank insulation. These passive storage concepts for deep space missions substantially improved this application of cryogenic propulsion. It is projected that for missions requiring larger propellant tank sizes, the results would be even more dramatic. 6. New Ti-decorated B40 fullerene as a promising hydrogen storage material. PubMed Dong, Huilong; Hou, Tingjun; Lee, Shuit-Tong; Li, Youyong 2015-05-06 The newly found B40 is the first experimentally observed all-boron fullerene and has potential applications in hydrogen storage. Here we investigate the binding ability and hydrogen storage capacity of Ti-decorated B40 fullerene based on DFT calculations. Our results indicate that Ti shows excellent binding capability to B40 compared with other transition metals. The B40 fullerene coated by 6 Ti atoms (Ti6B40) can store up to 34 H2 molecules, corresponding to a maximum gravimetric density of 8.7 wt%. It takes 0.2-0.4 eV/H2 to add one H2 molecule, which assures reversible storage of H2 molecules under ambient conditions. The evaluated reversible storage capacity is 6.1 wt%. Our results demonstrate that the new Ti-decorated B40 fullerene is a promising hydrogen storage material with high capacity. 7. Hydrogen Storage in Diamond Powder Utilizing Plasma NaF Surface Treatment for Fuel Cell Applications SciTech Connect Leal, David A.; Leal-Quiros, E.; Velez, Angel; Prelas, Mark A.; Gosh, Tushar 2006-12-04 Hydrogen Fuel Cells offer the vital solution to the world's socio-political dependence on oil. Due to existing difficulty in safe and efficient hydrogen storage for fuel cells, storing the hydrogen in hydrocarbon compounds such as artificial diamond is a realistic solution. By treating the surface of the diamond powder with a Sodium Fluoride plasma exposure, the surface of the diamond is cleaned of unwanted molecules. Due to fluorine's electro negativity, the diamond powder is activated and ready for hydrogen absorption. These diamond powder pellets are then placed on a graphite platform that is heated by conduction in a high voltage circuit made of tungsten wire. Then, the injection of hydrogen gas into chamber allows the storage of the Hydrogen on the surface of the diamond powder. By neutron bombardment in the nuclear reactor, or Prompt Gamma Neutron Activation Analysis, the samples are examined for parts per million amounts of hydrogen in the sample. Sodium Fluoride surface treatment allows for higher mass percentage of stored hydrogen in a reliable, resistant structure, such as diamond for fuel cells and permanently alters the diamonds terminal bonds for re-use in the effective storage of hydrogen. The highest stored amount utilizing the NaF plasma surface treatment was 22229 parts per million of hydrogen in the diamond powder which amounts to 2.2229% mass increase. 8. Modelling challenges for battery materials and electrical energy storage NASA Astrophysics Data System (ADS) Muller, Richard P.; Schultz, Peter A. 2013-10-01 Many vital requirements in world-wide energy production, from the electrification of transportation to better utilization of renewable energy production, depend on developing economical, reliable batteries with improved performance characteristics. Batteries reduce the need for gasoline and liquid hydrocarbons in an electrified transportation fleet, but need to be lighter, longer-lived and have higher energy densities, without sacrificing safety. Lighter and higher-capacity batteries make portable electronics more convenient. Less expensive electrical storage accelerates the introduction of renewable energy to electrical grids by buffering intermittent generation from solar or wind. Meeting these needs will probably require dramatic changes in the materials and chemistry used by batteries for electrical energy storage. New simulation capabilities, in both methods and computational resources, promise to fundamentally accelerate and advance the development of improved materials for electric energy storage. To fulfil this promise significant challenges remain, both in accurate simulations at various relevant length scales and in the integration of relevant information across multiple length scales. This focus section of Modelling and Simulation in Materials Science and Engineering surveys the challenges of modelling for energy storage, describes recent successes, identifies remaining challenges, considers various approaches to surmount these challenges and discusses the potential of these methods for future battery development. Zhang et al begin with atoms and electrons, with a review of first-principles studies of the lithiation of silicon electrodes, and then Fan et al examine the development and use of interatomic potentials to the study the mechanical properties of lithiated silicon in larger atomistic simulations. Marrocchelli et al study ionic conduction, an important aspect of lithium-ion battery performance, simulated by molecular dynamics. Emerging high 9. A Life Cycle Cost Analysis Framework for Geologic Storage of Hydrogen SciTech Connect Lord, Anna S.; Kobos, Peter Holmes; Borns, David James 2009-09-01 Large scale geostorage options for fuels including natural gas and petroleum offer substantial buffer capacity to meet or hedge against supply disruptions. This same notion may be applied to large scale hydrogen storage to meet industrial or transportation sector needs. This study develops an assessment tool to calculate the potential ‘gate-to-gate’ life cycle costs for large scale hydrogen geostorage options in salt caverns, and continues to develop modules for depleted oil/gas reservoirs and aquifers. The U.S. Department of Energy has an interest in these types of storage to assess the geological, geomechanical and economic viability for this type of hydrogen storage. Understanding, and looking to quantify, the value of large-scale storage in a larger hydrogen supply and demand infrastructure may prove extremely beneficial for larger infrastructure modeling efforts when looking to identify the most efficient means to fuel a hydrogen demand (e.g., industrial or transportation-centric demand). Drawing from the knowledge gained in the underground large scale storage options for natural gas and petroleum in the U.S., the potential to store relatively large volumes of CO2 in geological formations, the hydrogen storage assessment modeling will continue to build on these strengths while maintaining modeling transparency such that other modeling efforts may draw from this project. 10. Hydrogen storage in a chemical bond stabilized Co9S8-graphene layered structure NASA Astrophysics Data System (ADS) Qin, Wei; Han, Lu; Bi, Hai; Jian, Jiahuang; Wu, Xiaohong; Gao, Peng 2015-11-01 With the high energy ball milling method, a Co9S8-decorated reduced graphene oxide (RGO) composite, which shows excellent hydrogen storage capacity, has been successfully fabricated with a well-organized layered structure. Moreover, the stabilized mechanism of the well-organized layered structure is investigated and attributed to the strong interactions between Co9S8 and defective RGO. The C-S bond interaction is identified and the hydrogen storage process is also studied with different analysis methods. Finally, an optimized Co9S8 to RGO weight ratio of 6 : 1 shows excellent electrochemical performances in terms of the excellent cycling stability and competitive hydrogen storage capacity of 4.86 wt%.With the high energy ball milling method, a Co9S8-decorated reduced graphene oxide (RGO) composite, which shows excellent hydrogen storage capacity, has been successfully fabricated with a well-organized layered structure. Moreover, the stabilized mechanism of the well-organized layered structure is investigated and attributed to the strong interactions between Co9S8 and defective RGO. The C-S bond interaction is identified and the hydrogen storage process is also studied with different analysis methods. Finally, an optimized Co9S8 to RGO weight ratio of 6 : 1 shows excellent electrochemical performances in terms of the excellent cycling stability and competitive hydrogen storage capacity of 4.86 wt%. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr06116d 11. Investigation of hydrogen storage in MWCNT-TiO2 composite NASA Astrophysics Data System (ADS) Silambarasan, D.; Kanmani, M.; Iyakutti, K.; Jeyanthinath, M.; Ravindran, T. R.; Vasu, V. 2016-06-01 The hydrogen storage capacity of MWCNT-TiO2 composite has been evaluated in the present work. The composite has been prepared by means of ultrasonication followed by drop casting on substrates. Morphology, structural and functional group studies of the prepared samples are carried out by transmission electron microscopy (TEM), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. Then, the samples are hydrogenated in the hydrogenation chamber as a function of time. Hydrogen storage capacity of the composite sample is found to be 0.9 wt% at 100 °C. Hydrogen uptake of the composite is accounted for the spillover mechanism in CNTs-metal oxide composite. Desorption temperature range, activation energy of desorption, binding energy of hydrogen are determined from thermogravimetric (TG) analysis. 12. Combined hydrogen production and storage with subsequent carbon crystallization. PubMed Lueking, Angela D; Gutierrez, Humberto R; Fonseca, Dania A; Narayanan, Deepa L; Van Essendelft, Dirk; Jain, Puja; Clifford, Caroline E B 2006-06-21 We provide evidence of low-temperature hydrogen evolution and possible hydrogen trapping in an anthracite coal derivative, formed via reactive ball milling with cyclohexene. No molecular hydrogen is added to the process. Raman-active molecular hydrogen vibrations are apparent in samples at atmospheric conditions (300 K, 1 bar) for samples prepared 1 year previously and stored in ambient air. Hydrogen evolves slowly at room temperature and is accelerated upon sample heating, with a first increase in hydrogen evolution occurring at approximately 60 degrees C. Subsequent chemical modification leads to the observation of crystalline carbons, including nanocrystalline diamond surrounded by graphene ribbons, other sp2-sp3 transition regions, purely graphitic regions, and a previously unidentified crystalline carbon form surrounded by amorphous carbon. The combined evidence for hydrogen trapping and carbon crystallization suggests hydrogen-induced crystallization of the amorphous carbon materials, as metastable hydrogenated carbons formed via the high-energy milling process rearrange into more thermodynamically stable carbon forms and molecular hydrogen. 13. Rechargeable Hydrogen Storage System Based on the Dehydrogenative Coupling of Ethylenediamine with Ethanol. PubMed Hu, Peng; Ben-David, Yehoshoa; Milstein, David 2016-01-18 A novel and simple hydrogen storage system was developed, based on the dehydrogenative coupling of inexpensive ethylenediamine with ethanol to form diacetylethylenediamine. The system is rechargeable and utilizes the same ruthenium pincer catalyst for both hydrogen loading and unloading procedures. It is efficient and uses a low catalyst loading. Repetitive reversal reactions without addition of new catalyst result in excellent conversions in both the dehydrogenation and hydrogenation procedures in three cycles. PMID:26211515 14. Economic analysis of large-scale hydrogen storage for renewable utility applications. SciTech Connect Schoenung, Susan M. 2011-08-01 The work reported here supports the efforts of the Market Transformation element of the DOE Fuel Cell Technology Program. The portfolio includes hydrogen technologies, as well as fuel cell technologies. The objective of this work is to model the use of bulk hydrogen storage, integrated with intermittent renewable energy production of hydrogen via electrolysis, used to generate grid-quality electricity. In addition the work determines cost-effective scale and design characteristics and explores potential attractive business models. 15. Rechargeable Hydrogen Storage System Based on the Dehydrogenative Coupling of Ethylenediamine with Ethanol. PubMed Hu, Peng; Ben-David, Yehoshoa; Milstein, David 2016-01-18 A novel and simple hydrogen storage system was developed, based on the dehydrogenative coupling of inexpensive ethylenediamine with ethanol to form diacetylethylenediamine. The system is rechargeable and utilizes the same ruthenium pincer catalyst for both hydrogen loading and unloading procedures. It is efficient and uses a low catalyst loading. Repetitive reversal reactions without addition of new catalyst result in excellent conversions in both the dehydrogenation and hydrogenation procedures in three cycles. 16. Effects of storage on the cycle life of nickel hydrogen battery cells NASA Astrophysics Data System (ADS) Zimmerman, A. H.; Matsumoto, J.; Poston, T.; Prater, A.; Barrera, T. The cycle life of a nickel hydrogen cell has been evaluated at 80 percent depth of discharge after nearly 5 years of cell storage, including two years of shorted storage. After this storage the cycle life was found to be about 1200 cycles, compared to 5000-9000 cycles for typical unstored cells. Cell analyses before cycling indicated significant segregation of cobalt additive in the nickel electrodes, as well as a small amount of sinter corrosion. The large decrease in cycle life after storage is attributed primarily to the loss of about one-third of the active cobalt from the active material during the discharged storage of these hydrogen precharged cells, and to the formation of inactive cobalt oxides in the nickel electrodes. Storage methods capable of eliminating problems from both sinter corrosion and cobalt segregation are discussed. 17. Influence of the pore size in multi-walled carbon nanotubes on the hydrogen storage behaviors SciTech Connect Lee, Seul-Yi; Park, Soo-Jin 2012-10-15 Activated multi-walled carbon nanotubes (A-MWCNTs) were prepared using a chemical activation method to obtain well-developed pore structures for use as hydrogen storage materials. The microstructure and crystallinity of the A-MWCNTs were evaluated by X-ray diffraction and Fourier transform Raman spectroscopy. The textural properties of the A-MWCNTs were investigated by nitrogen gas sorption analysis at 77 K. The hydrogen storage capacity of the A-MWCNTs was evaluated at 77 K and 1 bar. The results showed that the specific surface area of the MWCNTs increased from 327 to 495 m{sup 2}/g as the activation temperature was increased. The highest hydrogen storage capacity was observed in the A-MWCNTs sample activated at 900 Degree-Sign C (0.54 wt%). This was attributed to it having the narrowest microporosity, which is a factor closely related to the hydrogen storage capacity. This shows that the hydrogen storage behaviors depend on the pore volume. Although a high pore volume is desirable for hydrogen storage, it is also severely affected if the pore size in the A-MWCNTs for the hydrogen molecules is suitable for creating the activation process. Highlights: Black-Right-Pointing-Pointer The AT-800 and AT-900 samples were prepared by a chemical activation method at activation temperature of 800 and 900 Degree-Sign C, respectively. Black-Right-Pointing-Pointer The AT-900 sample has the narrowest peak in comparison with the AT-800 sample, resulting from the overlap of the two peaks (Peak I and Peak II). Black-Right-Pointing-Pointer This overlapping effect is due to the newly created micropores or shrinkages of pores in Peak II. So, these determining characteristics are essential for designing materials that are suitable for molecular hydrogen storage. 18. Simulation of Porous Medium Hydrogen Storage - Estimation of Storage Capacity and Deliverability for a North German anticlinal Structure NASA Astrophysics Data System (ADS) Wang, B.; Bauer, S.; Pfeiffer, W. T. 2015-12-01 Large scale energy storage will be required to mitigate offsets between electric energy demand and the fluctuating electric energy production from renewable sources like wind farms, if renewables dominate energy supply. Porous formations in the subsurface could provide the large storage capacities required if chemical energy carriers such as hydrogen gas produced during phases of energy surplus are stored. This work assesses the behavior of a porous media hydrogen storage operation through numerical scenario simulation of a synthetic, heterogeneous sandstone formation formed by an anticlinal structure. The structural model is parameterized using data available for the North German Basin as well as data given for formations with similar characteristics. Based on the geological setting at the storage site a total of 15 facies distributions is generated and the hydrological parameters are assigned accordingly. Hydraulic parameters are spatially distributed according to the facies present and include permeability, porosity relative permeability and capillary pressure. The storage is designed to supply energy in times of deficiency on the order of seven days, which represents the typical time span of weather conditions with no wind. It is found that using five injection/extraction wells 21.3 mio sm³ of hydrogen gas can be stored and retrieved to supply 62,688 MWh of energy within 7 days. This requires a ratio of working to cushion gas of 0.59. The retrievable energy within this time represents the demand of about 450000 people. Furthermore it is found that for longer storage times, larger gas volumes have to be used, for higher delivery rates additionally the number of wells has to be increased. The formation investigated here thus seems to offer sufficient capacity and deliverability to be used for a large scale hydrogen gas storage operation. 19. Single walled carbon nanotube-metal oxide nanocomposites for reversible and reproducible storage of hydrogen. PubMed Silambarasan, D; Surya, V J; Vasu, V; Iyakutti, K 2013-11-13 Composite material consisting of single walled carbon nanotubes (SWCNTs) and metal oxide nanoparticles has been prepared and their hydrogen storage performance is evaluated. Metal oxides such as tin oxide (SnO2), tungsten trioxide (WO3), and titanium dioxide (TiO2) are chosen as the composite constituents. The composites have been prepared by means of ultrasonication. Then, the composite samples are deposited on alumina substrates and at 100 °C in a Sieverts-like hydrogenation setup. Characterization techniques such as transmission electron microscopy (TEM), Raman spectroscopy, scanning electron microscopy (SEM), powder X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, energy dispersive spectroscopy (EDS), CHN elemental analysis, and thermogravimetric (TG) measurements are used to analyze the samples at various stages of experiments. Hydrogen storage capacity of the composites namely, SWCNT-SnO2, SWCNT-WO3, and SWCNT-TiO2 are found to be 1.1, 0.9, and 1.3 wt %, respectively. Hydrogenated composite samples are stable at room temperature and desorption of hydrogen is found to be 100% reversible. Desorption temperature ranges and binding energy ranges of hydrogen have been measured from the desorption studies. The hydrogenation, dehydrogenation temperature, and binding energy of hydrogen fall in the recommended range of a suitable hydrogen storage medium applicable for fuel cell applications. Reproducibility and deterioration level of the composite samples have also been examined. PMID:24117025 20. Combined on-board hydride slurry storage and reactor system and process for hydrogen-powered vehicles and devices SciTech Connect Brooks, Kriston P; Holladay, Jamelyn D; Simmons, Kevin L; Herling, Darrell R 2014-11-18 An on-board hydride storage system and process are described. The system includes a slurry storage system that includes a slurry reactor and a variable concentration slurry. In one preferred configuration, the storage system stores a slurry containing a hydride storage material in a carrier fluid at a first concentration of hydride solids. The slurry reactor receives the slurry containing a second concentration of the hydride storage material and releases hydrogen as a fuel to hydrogen-power devices and vehicles. 1. Analysis of hydrogen vehicles with cryogenic high pressure storage SciTech Connect Aceves, S. M.; Berry, G. D. 1998-06-19 Insulated pressure vessels are cryogenic-capable pressure vessels that can be fueled with liquid hydrogen (LIQ) or ambient-temperature compressed hydrogen (CH2). Insulated pressure vessels offer the advantages of liquid hydrogen tanks (low weight and volume), with reduced disadvantages (lower energy requirement for hydrogen liquefaction and reduced evaporative losses). This paper shows an evaluation of the applicability of the insulated pressure vessels for light-duty vehicles. The paper shows an evaluation of evaporative losses and insulation requirements and a description of the current experimental plans for testing insulated pressure vessels. The results show significant advantages to the use of insulated pressure vessels for light-duty vehicles. 2. Tailoring of Single Walled Carbon Nanohorns for Hydrogen Storage and Catalyst Supports SciTech Connect Hu, Hui; Zhao, Bin; Puretzky, Alexander A; Rouleau, Christopher M; Styers-Barnett, David J; Geohegan, David B; Brown, Craig M.; Liu, Yun; Zhou, Wei; Kabbour, Houria; Neumann, Dan 2007-01-01 We report the post-processing chemical treatments of single walled carbon nanohorns (SWNHs) as a medium with tunable porosity to optimize hydrogen adsorption. Laser synthesized SWNHs are oxidized in air to achieve surface areas up to 1900 m2/g. Chemistry methods are described for the decoration of SWNHs with 1-3 nm Pt nanoparticles to probe spillover and metal-assisted hydrogen storage mechanisms. Hydrogen storage of opened SWNHs is 2.6 wt% at 77K, which is 3 times as that of as-prepared SWNHs. 3. Catalytic Metal Free Production of Large Cage Structure Carbon Particles: A Candidate for Hydrogen Storage NASA Technical Reports Server (NTRS) Kimura, Yuki; Nuth, Joseph A., III; Ferguson, Frank T. 2005-01-01 We will demonstrate that carbon particles consisting of large cages can be produced without catalytic metal. The carbon particles were produced in CO gas as well as by introduction of 5% methane gas into the CO gas. The gas-produced carbon particles were able to absorb approximately 16.2 wt% of hydrogen. This value is 2.5 times higher than the 6.5 wt% goal for the vehicular hydrogen storage proposed by the Department of Energy in the USA. Therefore, we believe that this carbon particle is an excellent candidate for hydrogen storage for fuel cells. 4. The storage of hydrogen in the form of metal hydrides: An application to thermal engines NASA Technical Reports Server (NTRS) Gales, C.; Perroud, P. 1981-01-01 The possibility of using LaNi56, FeTiH2, or MgH2 as metal hydride storage sytems for hydrogen fueled automobile engines is discussed. Magnesium copper and magnesium nickel hydrides studies indicate that they provide more stable storage systems than pure magnesium hydrides. Several test engines employing hydrogen fuel have been developed: a single cylinder motor originally designed for use with air gasoline mixture; a four-cylinder engine modified to run on an air hydrogen mixture; and a gas turbine. 5. Scenario Development and Analysis of Hydrogen as a Large-Scale Energy Storage Medium (Presentation) SciTech Connect Steward, D. M. 2009-06-10 The conclusions from this report are: (1) hydrogen has several important advantages over competing technologies, including - very high storage energy density (170 kWh/m{sup 3} vs. 2.4 for CAES and 0.7 for pumped hydro) which allows for potential economic viability of above-ground storage and relatively low environmental impact in comparison with other technologies; and (2) the major disadvantage of hydrogen energy storage is cost but research and deployment of electrolyzers and fuel cells may reduce cost significantly. 6. Effect of p-type multi-walled carbon nanotubes for improving hydrogen storage behaviors SciTech Connect Lee, Seul-Yi; Yop Rhee, Kyong; Nahm, Seung-Hoon; Park, Soo-Jin 2014-02-15 In this study, the hydrogen storage behaviors of p-type multi-walled carbon nanotubes (MWNTs) were investigated through the surface modification of MWNTs by immersing them in sulfuric acid (H{sub 2}SO{sub 4}) and hydrogen peroxide (H{sub 2}O{sub 2}) at various ratios. The presence of acceptor-functional groups on the p-type MWNT surfaces was confirmed by X-ray photoelectron spectroscopy. Measurement of the zeta-potential determined the surface charge transfer and dispersion of the p-type MWMTs, and the hydrogen storage capacity was evaluated at 77 K and 1 bar. From the results obtained, it was found that acceptor-functional groups were introduced onto the MWNT surfaces, and the dispersion of MWNTs could be improved depending on the acid-mixed treatment conditions. The hydrogen storage was increased by acid-mixed treatments of up to 0.36 wt% in the p-type MWNTs, compared with 0.18 wt% in the As-received MWNTs. Consequently, the hydrogen storage capacities were greatly influenced by the acceptor-functional groups of p-type MWNT surfaces, resulting in increased electron acceptor–donor interaction at the interfaces. - Graphical abstract: Hydrogen storage behaviors of the p-type MWNTs with the acid-mixed treatments are described. Display Omitted Display Omitted. 7. System simulation of compressed hydrogen storage based residential wind hybrid power systems NASA Astrophysics Data System (ADS) Raju, Mandhapati; Khaitan, Siddhartha Kumar 2012-07-01 This paper deals with the storage of excess wind energy, in a hybrid wind power system, in the form of compressed hydrogen. A system simulation model is developed in Matlab/Simulink platform for the charging and discharging dynamics of compressed hydrogen storage system integrated with the wind turbine and the fuel cell. Wind model is used to estimate the power generation in the wind turbine. When the wind power generation exceeds the load, the excess power is diverted to the electrolyzer to produce hydrogen. As and when the pressure inside the electrolyzer builds, a compressor is operated intermittently (for higher efficiency) to divert the hydrogen into high pressure cylinders. When demand exceeds the power generation, fuel cell supplies the power to the load. A number of fuel cell stacks are provided to meet the required load. The overall efficiency of the storage system, defined as the ratio of the useful energy derived from the storage system to the energy diverted to the storage system is found to be 24.5% for the compressed hydrogen storage based system. 8. Li and Ca Co-decorated carbon nitride nanostructures as high-capacity hydrogen storage media NASA Astrophysics Data System (ADS) Wang, Yusheng; Ji, Yong; Li, Meng; Yuan, Pengfei; Sun, Qiang; Jia, Yu 2011-11-01 Using first-principles method based on density functional theory, we perform a detailed study of the hydrogen storage properties of Li and Ca co-decorated graphene-like carbon nitride (g-CN) nanostructures. The results show that the average adsorption energy of the molecular hydrogen is ˜0.26 eV/H2, which is acceptable for reversible H2 adsorption/desorption near ambient temperature. Moreover, the findings also show that the storage capacity of the Li and Ca co-decorated g-CN can reach up to 9.17 wt %, presenting a good potential as hydrogen storage material. Regarding the H2 adsorption mechanism, it is demonstrated that the Li adatoms become positively charged through charge transferring to g-CN and then bind hydrogen molecules via the polarization mechanism. 9. Ideal metal-decorated three dimensional covalent organic frameworks for reversible hydrogen storage NASA Astrophysics Data System (ADS) Choi, Yoon Jeong; Lee, Jung Woo; Choi, Jung Hoon; Kang, Jeung Ku 2008-04-01 The most stable H2 adsorption on pure covalent organic frameworks (COFs) occurs near O atoms, but its binding energy (˜0.05eV) is not sufficient to satisfy the minimum value (0.24eV) required for practical applications. Meanwhile, Li and Mg ion-decorated COFs have hydrogen adsorption energies of 0.28 and 0.30eV, respectively, and their saturated hydrogen storage capacities exceed the DOE target (6.5wt%). Also the effect of some counterions on hydrogen storage has been explored. Moreover, doped ions prefer to exist as isolated elements on COFs, which is another advantage to realize hydrogen storage media. 10. Theoretical investigation of the borazine-melamine polymer as a novel candidate for hydrogen storage applications. PubMed Dabbagh, Hossein A; Shahraki, Maryam; Farrokhpour, Hossein 2014-06-14 Ab initio calculations and molecular dynamic simulation were employed to study the interaction of molecular hydrogen with the borazine-melamine polymer (BMP) in order to explore its potential for hydrogen storage applications. The calculations were performed using the long range corrected version of density functional theory, the Coulomb-attenuating method (CAM-B3LYP) and the second order Møller-Plesset perturbation theory (MP2). The results showed that the average adsorption energy per hydrogen is about -0.7 and -0.3 kcal mol(-1) at the MP2/6-311+G(d,p) and CAMB3LYP/6-311+G(d,p) levels of theory, respectively. The adsorption energies were corrected for the basis set superposition error (BSSE) by the counterpoise method. It was found that the hydrogen storage capacity of the BMP is about 6.49 wt%, which is close to the values reported for the other selected materials for the hydrogen storage in the literature. The maximum number of hydrogen molecules, which were adsorbed by the BMP building block, is about ten. Molecular dynamic simulation was performed to assess the potential of BMP for hydrogen storage. 11. HIERARCHICAL METHODOLOGY FOR MODELING HYDROGEN STORAGE SYSTEMS. PART I: SCOPING MODELS SciTech Connect Hardy, B; Donald L. Anton, D 2008-12-22 Detailed models for hydrogen storage systems provide essential design information about flow and temperature distributions, as well as, the utilization of a hydrogen storage media. However, before constructing a detailed model it is necessary to know the geometry and length scales of the system, along with its heat transfer requirements, which depend on the limiting reaction kinetics. More fundamentally, before committing significant time and resources to the development of a detailed model, it is necessary to know whether a conceptual storage system design is viable. For this reason, a hierarchical system of models progressing from scoping models to detailed analyses was developed. This paper, which discusses the scoping models, is the first in a two part series that presents a collection of hierarchical models for the design and evaluation of hydrogen storage systems. 12. Management of Leaks in Hydrogen Production, Delivery, and Storage Systems SciTech Connect Rawls, G 2006-04-27 A systematic approach to manage hydrogen leakage from components is presented. Methods to evaluate the quantity of hydrogen leakage and permeation from a system are provided by calculation and testing sensitivities. The following technology components of a leak management program are described: (1) Methods to evaluate hydrogen gas loss through leaks; (2) Methods to calculate opening areas of crack like defects; (3) Permeation of hydrogen through metallic piping; (4) Code requirements for acceptable flammability limits; (5) Methods to detect flammable gas; (6) Requirements for adequate ventilation in the vicinity of the hydrogen system; (7) Methods to calculate dilution air requirements for flammable gas mixtures; and (8) Concepts for reduced leakage component selection and permeation barriers. 13. High capacity hydrogen storage materials: attributes for automotive applications and techniques for materials discovery. PubMed Yang, Jun; Sudik, Andrea; Wolverton, Christopher; Siegel, Donald J 2010-02-01 Widespread adoption of hydrogen as a vehicular fuel depends critically upon the ability to store hydrogen on-board at high volumetric and gravimetric densities, as well as on the ability to extract/insert it at sufficiently rapid rates. As current storage methods based on physical means--high-pressure gas or (cryogenic) liquefaction--are unlikely to satisfy targets for performance and cost, a global research effort focusing on the development of chemical means for storing hydrogen in condensed phases has recently emerged. At present, no known material exhibits a combination of properties that would enable high-volume automotive applications. Thus new materials with improved performance, or new approaches to the synthesis and/or processing of existing materials, are highly desirable. In this critical review we provide a practical introduction to the field of hydrogen storage materials research, with an emphasis on (i) the properties necessary for a viable storage material, (ii) the computational and experimental techniques commonly employed in determining these attributes, and (iii) the classes of materials being pursued as candidate storage compounds. Starting from the general requirements of a fuel cell vehicle, we summarize how these requirements translate into desired characteristics for the hydrogen storage material. Key amongst these are: (a) high gravimetric and volumetric hydrogen density, (b) thermodynamics that allow for reversible hydrogen uptake/release under near-ambient conditions, and (c) fast reaction kinetics. To further illustrate these attributes, the four major classes of candidate storage materials--conventional metal hydrides, chemical hydrides, complex hydrides, and sorbent systems--are introduced and their respective performance and prospects for improvement in each of these areas is discussed. Finally, we review the most valuable experimental and computational techniques for determining these attributes, highlighting how an approach that 14. Analysis and Design of Cryogenic Pressure Vessels for Automotive Hydrogen Storage NASA Astrophysics Data System (ADS) Espinosa-Loza, Francisco Javier Cryogenic pressure vessels maximize hydrogen storage density by combining the high pressure (350-700 bar) typical of today's composite pressure vessels with the cryogenic temperature (as low as 25 K) typical of low pressure liquid hydrogen vessels. Cryogenic pressure vessels comprise a high-pressure inner vessel made of carbon fiber-coated metal (similar to those used for storage of compressed gas), a vacuum space filled with numerous sheets of highly reflective metalized plastic (for high performance thermal insulation), and a metallic outer jacket. High density of hydrogen storage is key to practical hydrogen-fueled transportation by enabling (1) long-range (500+ km) transportation with high capacity vessels that fit within available spaces in the vehicle, and (2) reduced cost per kilogram of hydrogen stored through reduced need for expensive structural material (carbon fiber composite) necessary to make the vessel. Low temperature of storage also leads to reduced expansion energy (by an order of magnitude or more vs. ambient temperature compressed gas storage), potentially providing important safety advantages. All this is accomplished while simultaneously avoiding fuel venting typical of cryogenic vessels for all practical use scenarios. This dissertation describes the work necessary for developing and demonstrating successive generations of cryogenic pressure vessels demonstrated at Lawrence Livermore National Laboratory. The work included (1) conceptual design, (2) detailed system design (3) structural analysis of cryogenic pressure vessels, (4) thermal analysis of heat transfer through cryogenic supports and vacuum multilayer insulation, and (5) experimental demonstration. Aside from succeeding in demonstrating a hydrogen storage approach that has established all the world records for hydrogen storage on vehicles (longest driving range, maximum hydrogen storage density, and maximum containment of cryogenic hydrogen without venting), the work also 15. A comparative analysis of the cryo-compression and cryo-adsorption hydrogen storage methods SciTech Connect Petitpas, G; Benard, P; Klebanoff, L E; Xiao, J; Aceves, S M 2014-07-01 While conventional low-pressure LH₂ dewars have existed for decades, advanced methods of cryogenic hydrogen storage have recently been developed. These advanced methods are cryo-compression and cryo-adsorption hydrogen storage, which operate best in the temperature range 30–100 K. We present a comparative analysis of both approaches for cryogenic hydrogen storage, examining how pressure and/or sorbent materials are used to effectively increase onboard H₂ density and dormancy. We start by reviewing some basic aspects of LH₂ properties and conventional means of storing it. From there we describe the cryo-compression and cryo-adsorption hydrogen storage methods, and then explore the relationship between them, clarifying the materials science and physics of the two approaches in trying to solve the same hydrogen storage task (~5–8 kg H₂, typical of light duty vehicles). Assuming that the balance of plant and the available volume for the storage system in the vehicle are identical for both approaches, the comparison focuses on how the respective storage capacities, vessel weight and dormancy vary as a function of temperature, pressure and type of cryo-adsorption material (especially, powder MOF-5 and MIL-101). By performing a comparative analysis, we clarify the science of each approach individually, identify the regimes where the attributes of each can be maximized, elucidate the properties of these systems during refueling, and probe the possible benefits of a combined “hybrid” system with both cryo-adsorption and cryo-compression phenomena operating at the same time. In addition the relationships found between onboard H₂ capacity, pressure vessel and/or sorbent mass and dormancy as a function of rated pressure, type of sorbent material and fueling conditions are useful as general designing guidelines in future engineering efforts using these two hydrogen storage approaches. 16. Preparation and hydrogen storage properties of nanostructured Mg 2Cu alloy NASA Astrophysics Data System (ADS) Shao, Huaiyu; Wang, Yuntao; Xu, Hairuo; Li, Xingguo 2005-07-01 We successfully synthesized Mg 2Cu alloys from the metal nanoparticles, which are produced from hydrogen plasma-metal reaction method, in two ways. One is under 0.1 MPa argon at 673 K and the other is under 4.0 MPa hydrogen at 673 K. The structure, morphology and reaction mechanism were studied. The hydrogen absorption and the pressure-composition isotherm properties of the obtained Mg 2Cu alloy under hydrogen were studied. The van't Hoff equation and the formation enthalpy and entropy of the resulting hydride (MgH 2+MgCu 2) were obtained from the equilibrium plateau pressures of the desorption isotherms. Nanostructured Mg 2Cu shows excellent hydrogen storage properties because nanostructured materials have more surface area and more defects, which means more nucleation sites with hydrogen, and smaller particles, which means shorter diffusion distance for hydrogen in the alloys particles. 17. A Radically New Method for Hydrogen Storage in Hollow Glass Microspheres SciTech Connect James E. Shelby; Matthew M. Hall; Fabienne C. Raszewski 2007-08-31 Photo-induced hydrogen diffusion has been applied to the problem of storage of high pressure hydrogen in hollow glass microspheres. Results of this study indicate that this phenomenon can be used to provide a high mass efficiency, safe, cheap, non-toxic method for storage of high pressure hydrogen. The photo-induced response is immediate upon exposure to infrared light for hollow glass microspheres doped with iron, nickel, or cobalt oxide, which is consistent with previous results for transition metal oxide-doped bulk glass samples. This effect is not observed for HGMS which do not contain these transition metal oxide, where the slight release of hydrogen observed occurs only by heating from absorption of the light. The initial rate of hydrogen release increases with increasing concentration of the metal oxide and with increasing hydrogen fill pressure within the microspheres. To date, hydrogen storage efficiencies of 2.2 wt% have been obtained, but results suggest that storage values can be increased to at least 6 wt%. Hydrogen losses over a 5 week period are minimal at room temperature in all compositions, with somewhat greater, but acceptable, losses at 50 C. Hollow glass microspheres have been produced from an alkali alkaline earth borosilicate glass containing either 1 or 5 wt% of the oxides of iron, nickel, and cobalt. Photo-driven gas diffusion has been demonstrated for these HGMS. Demonstration of photo-induced diffusion in these samples provides the first proof-of-concept for eventual applications of HGMS for large scale hydrogen storage. 18. From Fundamental Understanding To Predicting New Nanomaterials For High Capacity Hydrogen/Methane Storage and Carbon Capture SciTech Connect Yildirim, Taner 2015-03-03 On-board hydrogen/methane storage in fuel cell-powered vehicles is a major component of the national need to achieve energy independence and protect the environment. The main obstacles in hydrogen storage are slow kinetics, poor reversibility and high dehydrogenation temperatures for the chemical hydrides; and very low desorption temperatures/energies for the physisorption materials (MOF’s, porous carbons). Similarly, the current methane storage technologies are mainly based on physisorption in porous materials but the gravimetric and volumetric storage capacities are below the target values. Finally, carbon capture, a critical component of the mitigation of CO2 emissions from industrial plants, also suffers from similar problems. The solid-absorbers such as MOFs are either not stable against real flue-gas conditions and/or do not have large enough CO2 capture capacity to be practical and cost effective. In this project, we addressed these challenges using a unique combination of computational, synthetic and experimental methods. The main scope of our research was to achieve fundamental understanding of the chemical and structural interactions governing the storage and release of hydrogen/methane and carbon capture in a wide spectrum of candidate materials. We studied the effect of scaffolding and doping of the candidate materials on their storage and dynamics properties. We reviewed current progress, challenges and prospect in closely related fields of hydrogen/methane storage and carbon capture.[1-5] For example, for physisorption based storage materials, we show that tap-densities or simply pressing MOFs into pellet forms reduce the uptake capacities by half and therefore packing MOFs is one of the most important challenges going forward. For room temperature hydrogen storage application of MOFs, we argue that MOFs are the most promising scaffold materials for Ammonia-Borane (AB) because of their unique interior active metal-centers for AB binding and well 19. The synthesis and hydrogen storage properties of pure nanostructured Mg2FeH6. PubMed Zhang, Xuanzhou; Yang, Rong; Qu, Jianglan; Zhao, Wei; Xie, Lei; Tian, Wenhuai; Li, Xingguo 2010-03-01 In this work, pure nanostructured Mg(2)FeH(6) is successfully synthesized by sintering of a mixture of 2Mg + Fe nanoparticles. The successful preparation of pure Mg(2)FeH(6) can be attributed to the small particle sizes of Mg and Fe nanoparticles prepared by hydrogen plasma-metal reaction (HPMR), which benefits the synthesis. The hydrogen storage properties of Mg(2)FeH(6) and the synthesis mechanism of the Mg-Fe-H system are studied. The sample desorbs 5.0 wt% of hydrogen rapidly in 6 min under an initial hydrogen pressure of approximately 100 Pa at 623 K. The enthalpy and entropy of the reaction are deduced from the equilibrium plateau pressures of the desorption isotherms. The obtained Mg(2)FeH(6) shows favorable hydrogen storage properties due to the specific nanostructure of the materials. 20. Advancement of Systems Designs and Key Engineering Technologies for Materials Based Hydrogen Storage SciTech Connect van Hassel, Bart A. 2015-09-18 UTRC lead the development of the Simulink Framework model that enables a comparison of different hydrogen storage systems on a common basis. The Simulink Framework model was disseminated on the www.HSECoE.org website that is hosted by NREL. UTRC contributed to a better understanding of the safety aspects of the proposed hydrogen storage systems. UTRC also participated in the Failure Mode and Effect Analysis of both the chemical- and the adsorbent-based hydrogen storage system during Phase 2 of the Hydrogen Storage Engineering Center of Excellence. UTRC designed a hydrogen storage system with a reversible metal hydride material in a compacted form for light-duty vehicles with a 5.6 kg H2 storage capacity, giving it a 300 miles range. It contains a heat exchanger that enables efficient cooling of the metal hydride material during hydrogen absorption in order to meet the 3.3 minute refueling time target. It has been shown through computation that the kinetics of hydrogen absorption of Ti-catalyzed NaAlH4 was ultimately limiting the rate of hydrogen absorption to 85% of the material capacity in 3.3 minutes. An inverse analysis was performed in order to determine the material property requirements in order for a metal hydride based hydrogen storage system to meet the DOE targets. Work on metal hydride storage systems was halted after the Phase 1 to Phase 2 review due to the lack of metal hydride materials with the required material properties. UTRC contributed to the design of a chemical hydrogen storage system by developing an adsorbent for removing the impurity ammonia from the hydrogen gas, by developing a system to meter the transport of Ammonia Borane (AB) powder to a thermolysis reactor, and by developing a gas-liquid-separator (GLS) for the separation of hydrogen gas from AB slurry in silicone oil. Stripping impurities from hydrogen gas is essential for a long life of the fuel cell system on board of a vehicle. Work on solid transport of AB was halted after the 1. Electron-beam-induced information storage in hydrogenated amorphous silicon devices DOEpatents Yacobi, B.G. 1985-03-18 A method for recording and storing information in a hydrogenated amorphous silicon device, comprising: depositing hydrogenated amorphous silicon on a substrate to form a charge collection device; and generating defects in the hydrogenated amorphous silicon device, wherein the defects act as recombination centers that reduce the lifetime of carriers, thereby reducing charge collection efficiency and thus in the charge collection mode of scanning probe instruments, regions of the hydrogenated amorphous silicon device that contain the defects appear darker in comparison to regions of the device that do not contain the defects, leading to a contrast formation for pattern recognition and information storage. 2. Amine-free reversible hydrogen storage in formate salts catalyzed by ruthenium pincer complex without pH control or solvent change. PubMed Kothandaraman, Jotheeswari; Czaun, Miklos; Goeppert, Alain; Haiges, Ralf; Jones, John-Paul; May, Robert B; Prakash, G K Surya; Olah, George A 2015-04-24 Due to the intermittent nature of most renewable energy sources, such as solar and wind, energy storage is increasingly required. Since electricity is difficult to store, hydrogen obtained by electrochemical water splitting has been proposed as an energy carrier. However, the handling and transportation of hydrogen in large quantities is in itself a challenge. We therefore present here a method for hydrogen storage based on a CO2 (HCO3 (-) )/H2 and formate equilibrium. This amine-free and efficient reversible system (>90 % yield in both directions) is catalyzed by well-defined and commercially available Ru pincer complexes. The formate dehydrogenation was triggered by simple pressure swing without requiring external pH control or the change of either the solvent or the catalyst. Up to six hydrogenation-dehydrogenation cycles were performed and the catalyst performance remained steady with high selectivity (CO free H2 /CO2 mixture was produced). PMID:25824142 3. Amine-free reversible hydrogen storage in formate salts catalyzed by ruthenium pincer complex without pH control or solvent change. PubMed Kothandaraman, Jotheeswari; Czaun, Miklos; Goeppert, Alain; Haiges, Ralf; Jones, John-Paul; May, Robert B; Prakash, G K Surya; Olah, George A 2015-04-24 Due to the intermittent nature of most renewable energy sources, such as solar and wind, energy storage is increasingly required. Since electricity is difficult to store, hydrogen obtained by electrochemical water splitting has been proposed as an energy carrier. However, the handling and transportation of hydrogen in large quantities is in itself a challenge. We therefore present here a method for hydrogen storage based on a CO2 (HCO3 (-) )/H2 and formate equilibrium. This amine-free and efficient reversible system (>90 % yield in both directions) is catalyzed by well-defined and commercially available Ru pincer complexes. The formate dehydrogenation was triggered by simple pressure swing without requiring external pH control or the change of either the solvent or the catalyst. Up to six hydrogenation-dehydrogenation cycles were performed and the catalyst performance remained steady with high selectivity (CO free H2 /CO2 mixture was produced). 4. A Biomimetic Approach to New Adsorptive Hydrogen Storage Metal-Organic Frameworks SciTech Connect Zhou, Hongcai J 2015-08-12 In the past decades, there has been an escalation of interest in the study of MOFs due to their fascinating structures and intriguing application potentials. Their exceptionally high surface areas, uniform yet tunable pore sizes, and well-defined adsorbate-MOF interaction sites make them suitable for hydrogen storage. Various strategies to increase the hydrogen capacity of MOFs, such as constructing pore sizes comparable to hydrogen molecules, increasing surface area and pore volume, utilizing catenation, and introducing coordinatively unsaturated metal centers (UMCs) have been widely explored to increase the hydrogen uptake of the MOFs. MOFs with hydrogen uptake approaching the DOE gravimetric storage goal under reasonable pressure but cryo- temperature (typically 77 K) were achieved. However, the weak interaction between hydrogen molecules and MOFs has been the major hurdle limiting the hydrogen uptake of MOFs at ambient temperature. Along the road, we have realized both high surface area and strong interaction between framework and hydrogen are equally essential for porous materials to be practically applicable in Hydrogen storage. Increasing the isosteric heats of adsorption for hydrogen through the introduction of active centers into the framework could have great potential on rendering the framework with strong interaction toward hydrogen. Approaches on increasing the surface areas and improving hydrogen affinity by optimizing size and structure of the pores and the alignment of active centers around the pores in frameworks have been pursued, for example: (a) the introduction of coordinatively UMC (represents a metal center missing multiple ligands) with potential capability of multiple dihydrogen-binding (Kubas type, non-dissociative) per UMC, (b) the design and synthesis of proton-rich MOFs in which a + H3 binds dihydrogen just like a metal ion does, and (c) the preparation of MOFs and PPNs with well aligned internal electric fields. We believe the 5. Hydrogen Storage in the Carbon Dioxide - Formic Acid Cycle. PubMed Fink, Cornel; Montandon-Clerc, Mickael; Laurenczy, Gabor 2015-01-01 This year Mankind will release about 39 Gt carbon dioxide into the earth's atmosphere, where it acts as a greenhouse gas. The chemical transformation of carbon dioxide into useful products becomes increasingly important, as the CO(2) concentration in the atmosphere has reached 400 ppm. One approach to contribute to the decrease of this hazardous emission is to recycle CO(2), for example reducing it to formic acid. The hydrogenation of CO(2) can be achieved with a series of catalysts under basic and acidic conditions, in wide variety of solvents. To realize a hydrogen-based charge-discharge device ('hydrogen battery'), one also needs efficient catalysts for the reverse reaction, the dehydrogenation of formic acid. Despite of the fact that the overwhelming majority of these reactions are carried out using precious metals-based catalysts (mainly Ru), we review here developments for catalytic hydrogen evolution from formic acid with iron-based complexes. PMID:26842324 6. Thermodynamics of insulated pressure vessels for vehicular hydrogen storage SciTech Connect Aceves, S.M.; Berry, G.D. 1997-06-01 This paper studies the application of insulated pressure vessels for hydrogen-fueled light-duty vehicles. Insulated pressure vessels can store liquid hydrogen (LH2); low-temperature (90 K) compressed hydrogen (CH2); or ambient temperature CH2. In this analysis, hydrogen temperatures, pressures and venting losses am calculated for insulated pressure vessels fueled with LH2 or with low-temperature CH2, and the results are compared to those obtained in low-pressure LH2 tanks. Hydrogen losses are calculated as a function of daily driving distance during normal operation; as a function of time during long periods of vehicle inactivity; and as a function of initial vessel temperature during fueling. The number of days before any venting losses occur is also calculated as a function of the daily driving distance. The results show that insulated pressure vessels have packaging characteristics comparable to those of conventional, low-pressure LH2 tanks (low weight and volume), with greatly improved dormancy and much lower boil-off. Insulated pressure vessels used in a 17 km/l (40 mpg) car do not lose any hydrogen when the car is driven at least 15 km/day in average. Since almost all cars are driven for longer distances, most cars would never lose any hydrogen. Losses during long periods of parking are also relatively small. Due to their high-pressure capacity, these vessels would retain about a third of their full charge even after a very long dormancy, so that the owner would not risk running out of fuel. If an insulated pressure vessel reaches ambient temperature, it can be cooled down very effectively by fueling it with LH2 with no losses during fueling. The vessel has good thermal performance even when thermally insulated with inexpensive microsphere insulation. In addition, the insulated pressure vessels greatly ease fuel availability and infrastructure requirements, since it would be compatible with both compressed and cryogenic hydrogen reveling. 7. Influence of CO 2 activation on hydrogen storage behaviors of platinum-loaded activated carbon nanotubes NASA Astrophysics Data System (ADS) Lee, Seul-Yi; Park, Soo-Jin 2010-12-01 In this work, platinum (Pt) metal loaded activated multi-walled carbon nanotubes (MWNTs) were prepared with different structural characteristics for hydrogen storage applications. The process was conducted by a gas phase CO 2 activation method at 1200 °C as a function of the CO 2 flow time. Pt-loaded activated MWNTs were also formulated to investigate the hydrogen storage characteristics. The microstructures of the Pt-loaded activated MWNTs were characterized by XRD and TEM measurements. The textural properties of the samples were analyzed using N 2 adsorption isotherms at 77 K. The BET, D-R, and BJH equations were used to observe the specific surface areas and the micropore and mesopore structures. The hydrogen storage capacity of the Pt-loaded activated MWNTs was measured at 298 K at a pressure of 100 bar. The hydrogen storage capacity was increased with CO 2 flow time. It was found that the micropore volume of the activated MWNTs plays a key role in the hydrogen storage capacity. 8. Sub-Nanostructured Non Transition Metal Complex Grids for Hydrogen Storage SciTech Connect Dr. Orhan Talu; Dr. Surendra N. Tewari 2007-10-27 This project involved growing sub-nanostructured metal grids to increase dynamic hydrogen storage capacity of metal hydride systems. The nano particles of any material have unique properties unlike its bulk form. Nano-structuring metal hydride materials can result in: {sm_bullet}Increased hydrogen molecule dissociation rate, {sm_bullet} Increased hydrogen atom transport rate, {sm_bullet} Decreased decrepitation caused by cycling, {sm_bullet} Increased energy transfer in the metal matrix, {sm_bullet} Possible additional contribution by physical adsorption, and {sm_bullet} Possible additional contribution by quantum effects The project succeeded in making nano-structured palladium using electrochemical growth in templates including zeolites, mesoporous silica, polycarbonate films and anodized alumina. Other metals were used to fine-tune the synthesis procedures. Palladium was chosen to demonstrate the effects of nano-structuring since its bulk hydrogen storage capacity and kinetics are well known. Reduced project funding was not sufficient for complete characterization of these materials for hydrogen storage application. The project team intends to seek further funding in the future to complete the characterization of these materials for hydrogen storage. 9. Studies on metal-organic frameworks of Cu(II) with isophthalate linkers for hydrogen storage. PubMed Yan, Yong; Yang, Sihai; Blake, Alexander J; Schröder, Martin 2014-02-18 Hydrogen (H2) is a promising alternative energy carrier because of its environmental benefits, high energy density, and abundance. However, development of a practical storage system to enable the "Hydrogen Economy" remains a huge challenge. Metal-organic frameworks (MOFs) are an important class of crystalline coordination polymers constructed by bridging metal centers with organic linkers. MOFs show promise for H2 storage owing to their high surface area and tuneable properties. In this Account, we summarize our research on novel porous materials with enhanced H2 storage properties and describe frameworks derived from 3,5-substituted dicarboxylates (isophthalates) that serve as versatile molecular building blocks for the construction of a range of interesting coordination polymers with Cu(II) ions. We synthesized a series of materials by connecting linear tetracarboxylate linkers to {Cu(II)2} paddlewheel moieties. These materials exhibit high structural stability and permanent porosity. Varying the organic linker modulates the pore size, geometry, and functionality to control the overall H2 adsorption. Our top-performing material in this series has a H2 storage capacity of 77.8 mg g(-1) at 77 K, 60 bar. H2 adsorption at low, medium, and high pressures correlates with the isosteric heat of adsorption, surface area, and pore volume, respectively. Another series, using tribranched C3-symmetric hexacarboxylate ligands with Cu(II), gives highly porous (3,24)-connected frameworks incorporating {Cu(II)2} paddlewheels. Increasing the length of the hexacarboxylate struts directly tunes the porosity of the resultant material from micro- to mesoporosity. These materials show exceptionally high H2 uptakes owing to their high surface area and pore volume. The first member of this family reported adsorbs 111 mg g(-1) of H2, or 55.9 g L(-1), at 77 K, 77 bar, while at 77 K, 1 bar, the material adsorbs 2.3 wt % H2. We and others have since achieved enhanced H2 adsorption in these 10. Design and reversible hydrogen storage capacity determination of unique nanoarrays of titanium dioxide and carbon nanotubes NASA Astrophysics Data System (ADS) Mishra, Amrita In this project hydrogen storage studies were carried out on TiO 2 nanotubular arrays of different diameters prepared by electrochemical anodization, combined with template-grown carbon nanotubes (CNTs). The growth of the CNTs on the nanotubular TiO2 arrays was accomplished by chemical vapor deposition. The hydrogen storage capacity was determined for the nanotubular TiO2 and the combined TiO2-CNT arrays, by charging and discharging hydrogen with a Sievert's apparatus. It was found that the presence of carbon nanotubes on nano-porous titanium oxide can enhance storage of hydrogen as determined by volumetric means. The hydrogen uptake in as-anodized TiO2 nanotubes was found to be 2 wt% at liquid nitrogen temperature (77 K) and 0.94 wt% at room temperature. Desorption results for TiO2 at 393 K and 300 K were 1.5 wt% and 0.7 wt%, respectively. The CNT-TiO2 composites showed a hydrogen uptake capacity of 1.94 wt% at room temperature and 2.5 wt% at 77 K. The desorption results were 1.8 wt% at 393 K and 0.68 wt% at room temperature. It was seen that the hydrogen uptake was higher at lower temperatures and discharge was increased significantly at higher temperatures for both TiO2 and CNT/TiO2 samples. The utilization of this novel hydrogen storage method can be recognized as a break-through in the hydrogen economy as applied to on-board vehicular applications. 11. Kinetics Study of Solid Ammonia Borane Hydrogen Release – Modeling and Experimental Validation for Chemical Hydrogen Storage SciTech Connect Choi, Yong-Joon; Ronnebro, Ewa; Rassat, Scot D.; Karkamkar, Abhijeet J.; Maupin, Gary D.; Holladay, Jamelyn D.; Simmons, Kevin L.; Brooks, Kriston P. 2014-02-24 Ammonia borane (AB), NH3BH3, is a promising material for chemical hydrogen storage with 19.6 wt% gravimetric hydrogen capacity of which 16.2 wt% hydrogen can be utilized below 200°C. We have investigated the kinetics of hydrogen release from AB and from an AB-methyl cellulose (AB/MC) composite at temperatures of 160-300°C using both experiments and modeling. The purpose of our study was to show safe hydrogen release without thermal runaway effects and to validate system model kinetics. AB/MC released hydrogen at ~20°C lower than neat AB and at a rate that is two times faster. Based on the experimental results, the kinetics equations were revised to better represent the growth and nucleation process during decomposition of AB. We explored two different reactor concepts; Auger and fixed bed. The current Auger reactor concept turned out to not be appropriate, however, we demonstrated safe self-propagation of the hydrogen release reaction of solid AB/MC in a fixed bed reactor. 12. A life cycle cost analysis framework for geologic storage of hydrogen : a user's tool. SciTech Connect Kobos, Peter Holmes; Lord, Anna Snider; Borns, David James; Klise, Geoffrey T. 2011-09-01 The U.S. Department of Energy (DOE) has an interest in large scale hydrogen geostorage, which could offer substantial buffer capacity to meet possible disruptions in supply or changing seasonal demands. The geostorage site options being considered are salt caverns, depleted oil/gas reservoirs, aquifers and hard rock caverns. The DOE has an interest in assessing the geological, geomechanical and economic viability for these types of geologic hydrogen storage options. This study has developed an economic analysis methodology and subsequent spreadsheet analysis to address costs entailed in developing and operating an underground geologic storage facility. This year the tool was updated specifically to (1) incorporate more site-specific model input assumptions for the wells and storage site modules, (2) develop a version that matches the general format of the HDSAM model developed and maintained by Argonne National Laboratory, and (3) incorporate specific demand scenarios illustrating the model's capability. Four general types of underground storage were analyzed: salt caverns, depleted oil/gas reservoirs, aquifers, and hard rock caverns/other custom sites. Due to the substantial lessons learned from the geological storage of natural gas already employed, these options present a potentially sizable storage option. Understanding and including these various geologic storage types in the analysis physical and economic framework will help identify what geologic option would be best suited for the storage of hydrogen. It is important to note, however, that existing natural gas options may not translate to a hydrogen system where substantial engineering obstacles may be encountered. There are only three locations worldwide that currently store hydrogen underground and they are all in salt caverns. Two locations are in the U.S. (Texas), and are managed by ConocoPhillips and Praxair (Leighty, 2007). The third is in Teeside, U.K., managed by Sabic Petrochemicals (Crotogino et 13. Hydrogen storage behaviors of Ni-doped graphene Oxide/MIL-101 hybrid composites. PubMed Lee, Seul-Yi; Park, Soo-Jin 2013-01-01 In this work, Ni-doped graphene oxide/MIL-101 hybrid composites (Ni--GO/MIL) were prepared to investigate their hydrogen storage behaviors. Ni--GO/MIL was synthesized by adding Ni--GO in situ during the synthesis of MIL-101 using a hydrothermal process, which was conducted by conventional convection heating with Cr(III) ion as a metal center and telephthalic acid as organic ligands. The crystalline structures and morphologies were measured by X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The specific surface area and micropore volume were investigated by N2/77 K adsorption isotherms using the Brunauer-Emmett-Teller (BET) method and Dubinin-Radushkevic (D-R) equation, respectively. The hydrogen storage capacity was investigated by BEL-HP at 77 K and 1 bar. The obtained results show that Ni--GO/MIL presents new directions for achieving novel hybrid materials with higher hydrogen storage capacity. 14. Hydrogen storage in a chemical bond stabilized Co9S8-graphene layered structure. PubMed Qin, Wei; Han, Lu; Bi, Hai; Jian, Jiahuang; Wu, Xiaohong; Gao, Peng 2015-12-21 With the high energy ball milling method, a Co9S8-decorated reduced graphene oxide (RGO) composite, which shows excellent hydrogen storage capacity, has been successfully fabricated with a well-organized layered structure. Moreover, the stabilized mechanism of the well-organized layered structure is investigated and attributed to the strong interactions between Co9S8 and defective RGO. The C-S bond interaction is identified and the hydrogen storage process is also studied with different analysis methods. Finally, an optimized Co9S8 to RGO weight ratio of 6:1 shows excellent electrochemical performances in terms of the excellent cycling stability and competitive hydrogen storage capacity of 4.86 wt%. 15. First-principles study of hydrogen storage on Ti-decorated B2C sheet NASA Astrophysics Data System (ADS) Guo, Y. H.; Xu, B.; Xia, Y. D.; Yin, J.; Liu, Z. G. 2012-06-01 The hydrogen storage capacity of Ti decorated B2C sheet has been investigated by first-principles plane-wave calculation. It is revealed that a single Ti atom adsorbed on the B2C sheet can strongly bind up to four hydrogen molecules. The adsorption energy is in the range of -0.36--0.82 eV/H2, which is suitable for ambient temperature hydrogen storage. Considering the fact that Ti can be loaded on both sides of B2C sheet, corresponding gravimetric storage capacity of Ti/B2C system was also calculated and it can reach to about 7.0 wt%, exceeding the minimum requirement of 6.0 wt% for applications. 16. Underwater Explosion Analysis of Hexogen-Enriched Novel Hydrogen Storage Alloy NASA Astrophysics Data System (ADS) Chen, Yuan; Chen, Xiang; Wu, Dejun; Xu, Sen; Liu, Dabin; Xu, Minxiao 2016-01-01 A novel hydrogen storage alloy was used in hexogen-based thermobaric explosive (RDX-based TBE). Two types of fashioned explosive charges with mass of 160 g and 500 g were used in this work. The energy of TBE was tested by underwater explosion. The results indicate hexogen-enriched novel hydrogen storage alloy can produce higher bubble energy than that enriched aluminum. The total useful energy was 4.7 % (160 g) and 6.4 % (500 g) higher than an explosive with the same aluminum content, and Trotyl (TNT) equivalent of 2.1 times. The heat of explosion test shows the similar result that the novel hydrogen storage alloy can improve the total energy, about 7.9 % higher than the aluminized. 17. The usable capacity of porous materials for hydrogen storage NASA Astrophysics Data System (ADS) Schlichtenmayer, Maurice; Hirscher, Michael 2016-04-01 A large number of different porous materials has been investigated for their hydrogen uptake over a wide pressure range and at different temperature. From the absolute adsorption isotherms, the enthalpy of adsorption is evaluated for a wide range of surface coverage. The usable capacity, defined as the amount of hydrogen released between a maximum tank pressure and a minimum back pressure for a fuel cell, is analyzed for isothermal operation. The usable capacity as a function of temperature shows a maximum which defines the optimum operating temperature. This optimum operating temperature is higher for materials possessing a higher enthalpy of adsorption. However, the fraction of the hydrogen stored overall that can be released at the optimum operating temperature is higher for materials with a lower enthalpy of adsorption than for the ones with higher enthalpy. 18. Characterization and high throughput analysis of metal hydrides for hydrogen storage NASA Astrophysics Data System (ADS) Barcelo, Steven James Efficient hydrogen storage is required for fuel cell vehicles to be competitive with those driven by internal combustion engines. Current methods of storage such as compressed gas and liquid hydrogen cannot meet this standard, so novel hydrogen storage materials such as metal hydrides are required. No simple metal hydride meets the required specifications. Research is required to find new materials or improve existing materials. This thesis describes the research practices necessary to achieve legitimate and repeatable results in laboratories across the world. Examples of experiments using these techniques are presented, such as a high throughput technique to optimize materials systems with up to three components such as calcium borohydride with titanium catalyst and magnesium hydride with nickel and aluminum as destabilizing elements and catalysts. Thin films composed of gradients of each material were deposited by sputtering, creating a single thin film sample covering all potential material combinations. Optical properties of the samples under hydrogen pressure were monitored to identify the regions with largest and fastest hydrogen uptake. In the Ca-B-Ti system, titanium did not sufficiently catalyze the borohydride formation reaction at low temperature. Substantial hydrogen uptake was shown in the Mg-Ni region of the Mg-Ni-Al films. Al did not participate in the reaction at low temperature. Further investigation of the role of catalysts and destabilizing elements in improving hydrogen storage performance through X-ray Absorption and Emission Spectroscopy measurements of the Mg-Ni system during hydrogenation is presented. Typical X-ray spectroscopy measurements use a synchrotron radiation source and require ultra high vacuum conditions. For these experiments we designed a chamber which can be inserted into a vacuum chamber allowing in situ measurements of a sample under hydrogen pressure, providing information on the role of Ni in hydrogen absorption of Mg 19. Si-decorated graphene: A promising media for molecular hydrogen storage NASA Astrophysics Data System (ADS) Ganji, M. Darvish; Emami, S. N.; Khosravi, A.; Abbasi, M. 2015-03-01 The adsorption of hydrogen molecules (H2) on Si-decorated graphene was studied by using density functional theory calculations based on local density approximation (LDA). The accuracy of our method was validated by high level quantum chemical calculation result at MP2 level of theory for similar system. Our calculations show that Si-decorated graphene has high adsorption energy, high net charge transfer values and small connecting distances to graphene surface due to chemisorption. This makes adsorbed Si on the surface as a positive center which can adsorb considerably H2 molecules. We find that up to 16 H2 molecules can stably bind to two Si atoms on both side of the graphene sheet with slightly desirable adsorption energy which indicates that the resultant system facilitates the hydrogen desorption at near ambient conditions for practical applications. This newly developed Si decorated graphene with its hydrogen storage capacity of about 15 wt% would be an excellent candidate for hydrogen storage mediums. 20. [Ca(BH4)2] n clusters as hydrogen storage material: A DFT study NASA Astrophysics Data System (ADS) Han, Cuiling; Dong, Yanyun; Wang, Bingqiang; Zhang, Caiyun 2016-10-01 Calcium borohydride is widely studied as a hydrogen storage material. However, investigations on calcium borohydride from a cluster perspective are seldom found. The geometric structures and binding energies of [Ca(BH4)2] n ( n = 1-4) clusters are determined using density function theory (DFT). For the most stable structures, vibration frequency, natural bond orbital (NBO) are calculated and discussed. The charge transfer from (BH4) to Ca was observed. Meanwhile, we also study the LUMO-HOMO gap ( E g) and the B-H bond dissociation energies (BDEs). [Ca(BH4)2]3 owns higher E g, revealing that trimer is more stable than the other forms. Structures don't change during optimization after hydrogen radical removal, showing that calcium borohydride could possibly be used as a reversible hydrogen storage material. [Ca(BH4)2]4 has the smallest dissociation energy suggesting it releases hydrogen more easily than others. 1. Fabrication of a three-electrode battery using hydrogen-storage materials NASA Astrophysics Data System (ADS) Roh, Chi-Woo; Seo, Jung-Yong; Moon, Hyung-Seok; Park, Hyun-Young; Nam, Na-Yun; Cho, Sung Min; Yoo, Pil J.; Chung, Chan-Hwa 2015-04-01 In this study, an energy storage device using a three-electrode battery is fabricated. The charging process takes place during electrolysis of the alkaline electrolyte where hydrogen is stored at the palladium bifunctional electrode. Upon discharging, power is generated by operating the alkaline fuel cell using hydrogen which is accumulated in the palladium hydride bifunctional electrode during the charging process. The bifunctional palladium electrode is prepared by electrodeposition using a hydrogen bubble template followed by a galvanic displacement reaction of platinum in order to functionalize the electrode to work not only as a hydrogen storage material but also as an anode in a fuel cell. This bifunctional electrode has a sufficiently high surface area and the platinum catalyst populates at the surface of electrode to operate the fuel cell. The charging and discharging performance of the three-electrode battery are characterized. In addition, the cycle stability is investigated. 2. The role of ionic liquids in hydrogen storage. PubMed Sahler, Sebastian; Sturm, Sebastian; Kessler, Michael T; Prechtl, Martin H G 2014-07-14 Ionic liquid (IL) based H2 storage for H2 generation from NH3BH3 derivatives is shown. These systems promote H2 generation at low temperature, with good reaction rates and high total H2 yields. The effects of ILs and the H2 yield in correlation with the basicity, the cations of the ILs, and the role of carbenes are discussed. Furthermore, mechanistic findings on the dehydrogenation are described. IL material blends are competitive with conventional H2 storage materials with experimental efficiencies of at least 6.5 wt % H2. 3. Hydrogen storage materials. (Latest citations from the US Patent Bibliographic file with exemplary claims). Published Search SciTech Connect 1996-11-01 The bibliography contains citations of selected patents concerning the manufacture of hydrogen storage materials for use in batteries and elecrochemical cells. Citations present the design and production of high capacity, rechargeable metal hydride batteries and cells. Hydrogen-storing characteristics, charging and discharging performance, cost reduction, and battery life are discussed. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995) 4. Technical Assessment of Organic Liquid Carrier Hydrogen Storage Systems for Automotive Applications SciTech Connect Ahluwalia, R. K.; Hua, T. Q.; Peng, J. -K; Kromer, M.; Lasher, S.; McKenney, K.; Law, K.; Sinha, J. 2011-06-21 In 2007-2009, the DOE Hydrogen Program conducted a technical assessment of organic liquid carrier based hydrogen storage systems for automotive applications, consistent with the Program’s Multiyear Research, Development, and Demonstration Plan. This joint performance (ANL) and cost analysis (TIAX) report summarizes the results of this assessment. These results should be considered only in conjunction with the assumptions used in selecting, evaluating, and costing the systems discussed here and in the Appendices. 5. An overview—Functional nanomaterials for lithium rechargeable batteries, supercapacitors, hydrogen storage, and fuel cells SciTech Connect Liu, Hua Kun 2013-12-15 Graphical abstract: Nanomaterials play important role in lithium ion batteries, supercapacitors, hydrogen storage and fuel cells. - Highlights: • Nanomaterials play important role for lithium rechargeable batteries. • Nanostructured materials increase the capacitance of supercapacitors. • Nanostructure improves the hydrogenation/dehydrogenation of hydrogen storage materials. • Nanomaterials enhance the electrocatalytic activity of the catalysts in fuel cells. - Abstract: There is tremendous worldwide interest in functional nanostructured materials, which are the advanced nanotechnology materials with internal or external dimensions on the order of nanometers. Their extremely small dimensions make these materials unique and promising for clean energy applications such as lithium ion batteries, supercapacitors, hydrogen storage, fuel cells, and other applications. This paper will highlight the development of new approaches to study the relationships between the structure and the physical, chemical, and electrochemical properties of functional nanostructured materials. The Energy Materials Research Programme at the Institute for Superconducting and Electronic Materials, the University of Wollongong, has been focused on the synthesis, characterization, and applications of functional nanomaterials, including nanoparticles, nanotubes, nanowires, nanoporous materials, and nanocomposites. The emphases are placed on advanced nanotechnology, design, and control of the composition, morphology, nanostructure, and functionality of the nanomaterials, and on the subsequent applications of these materials to areas including lithium ion batteries, supercapacitors, hydrogen storage, and fuel cells. 6. High performance hydrogen storage from Be-BTB metal-organic framework at room temperature. PubMed Lim, Wei-Xian; Thornton, Aaron W; Hill, Anita J; Cox, Barry J; Hill, James M; Hill, Matthew R 2013-07-01 The metal-organic framework beryllium benzene tribenzoate (Be-BTB) has recently been reported to have one of the highest gravimetric hydrogen uptakes at room temperature. Storage at room temperature is one of the key requirements for the practical viability of hydrogen-powered vehicles. Be-BTB has an exceptional 298 K storage capacity of 2.3 wt % hydrogen. This result is surprising given that the low adsorption enthalpy of 5.5 kJ mol(-1). In this work, a combination of atomistic simulation and continuum modeling reveals that the beryllium rings contribute strongly to the hydrogen interaction with the framework. These simulations are extended with a thermodynamic energy optimization (TEO) model to compare the performance of Be-BTB to a compressed H2 tank and benchmark materials MOF-5 and MOF-177 in a MOF-based fuel cell. Our investigation shows that none of the MOF-filled tanks satisfy the United States Department of Energy (DOE) storage targets within the required operating temperatures and pressures. However, the Be-BTB tank delivers the most energy per volume and mass compared to the other material-based storage tanks. The pore size and the framework mass are shown to be contributing factors responsible for the superior room temperature hydrogen adsorption of Be-BTB. 7. Dynamic Modeling and Simulation Based Analysis of an Ammonia Borane (AB) Reactor System for Hydrogen Storage SciTech Connect Devarakonda, Maruthi N.; Holladay, Jamelyn D.; Brooks, Kriston P.; Rassat, Scot D.; Herling, Darrell R. 2010-10-02 Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydrogen storage in PEM fuel cell applications. AB was selected by DOE’s Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of three molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A model of a bead reactor system which includes feed and product tanks, hot and cold augers, a ballast tank/reactor, a H2 burner and a radiator was developed to study AB system performance in an automotive application and estimate the energy, mass, and volume requirements for this off-board regenerable hydrogen storage material. Preliminary system simulation results for a start-up case and for a transient drive cycle indicate appropriate trends in the reactor system dynamics. A new controller was developed and validated in simulation for a couple of H2 demand cases. 8. Synthesis and Engineering Materials Properties of Fluid Phase Chemical Hydrogen Storage Materials for Automotive Applications SciTech Connect Choi, Young Joon; Westman, Matthew P.; Karkamkar, Abhijeet J.; Chun, Jaehun; Ronnebro, Ewa 2015-09-01 Among candidates for chemical hydrogen storage in PEM fuel cell automotive applications, ammonia borane (AB, NH3BH3) is considered to be one of the most promising materials due to its high practical hydrogen content of 14-16 wt%. This material is selected as a surrogate chemical for a hydrogen storage system. For easier transition to the existing infrastructure, a fluid phase hydrogen storage material is very attractive and thus, we investigated the engineering materials properties of AB in liquid carriers for a chemical hydrogen storage slurry system. Slurries composed of AB and high temperature liquids were prepared by mechanical milling and sonication in order to obtain stable and fluidic properties. Volumetric gas burette system was adopted to observe the kinetics of the H2 release reactions of the AB slurry and neat AB. Viscometry and microscopy were employed to further characterize slurries engineering properties. Using a tip-sonication method we have produced AB/silicone fluid slurries at solid loadings up to 40wt% (6.5wt% H2) with viscosities less than 500cP at 25°C. 9. Pressure Relief Devices for High-Pressure Gaseous Storage Systems: Applicability to Hydrogen Technology SciTech Connect Kostival, A.; Rivkin, C.; Buttner, W.; Burgess, R. 2013-11-01 Pressure relief devices (PRDs) are viewed as essential safety measures for high-pressure gas storage and distribution systems. These devices are used to prevent the over-pressurization of gas storage vessels and distribution equipment, except in the application of certain toxic gases. PRDs play a critical role in the implementation of most high-pressure gas storage systems and anyone working with these devices should understand their function so they can be designed, installed, and maintained properly to prevent any potentially dangerous or fatal incidents. As such, the intention of this report is to introduce the reader to the function of the common types of PRDs currently used in industry. Since high-pressure hydrogen gas storage systems are being developed to support the growing hydrogen energy infrastructure, several recent failure incidents, specifically involving hydrogen, will be examined to demonstrate the results and possible mechanisms of a device failure. The applicable codes and standards, developed to minimize the risk of failure for PRDs, will also be reviewed. Finally, because PRDs are a critical component for the development of a successful hydrogen energy infrastructure, important considerations for pressure relief devices applied in a hydrogen gas environment will be explored. 10. Hydrogen sulfide release from dairy manure storages containing gypsum bedding Technology Transfer Automated Retrieval System (TEKTRAN) Recycled gypsum products can provide a cost-effective bedding alternative for dairy producers. Manufacturers report reduced odors, moisture and bacteria in the stall environment when compared to traditional bedding. Gypsum provides a sulfate source that can be converted to hydrogen sulfide under ana... 11. Development and validation of a slurry model for chemical hydrogen storage in fuel cell vehicle applications NASA Astrophysics Data System (ADS) Brooks, Kriston P.; Pires, Richard P.; Simmons, Kevin L. 2014-12-01 The U.S. Department of Energy's (DOE) Hydrogen Storage Engineering Center of Excellence (HSECoE) is developing models for hydrogen storage systems for fuel cell-based light duty vehicle applications for a variety of promising materials. These transient models simulate the performance of the storage system for comparison to the DOE's Technical Targets and a set of four drive cycles. PNNL developed models to simulate the performance and suitability of slurry-based chemical hydrogen storage materials. The storage systems of both a representative exothermic system based on ammonia borane and an endothermic system based on alane were developed and modeled in Simulink®. Once complete, the reactor and radiator components of the model were validated with experimental data. The system design parameters were adjusted to allow the model to successfully meet a highway cycle, an aggressive cycle, a cold-start cycle, and a hot drive cycle. Finally, a sensitivity analysis was performed to identify the range of material properties where these DOE targets and drive cycles could be met. Materials with a heat of reaction >11 kJ mol-1 H2 generated and a slurry hydrogen capacity of >11.4% will meet the on-board efficiency and gravimetric capacity targets, respectively. 12. Charge Modulation in Graphitic Carbon Nitride as a Switchable Approach to High-Capacity Hydrogen Storage. PubMed Tan, Xin; Kou, Liangzhi; Tahini, Hassan A; Smith, Sean C 2015-11-01 Electrical charging of graphitic carbon nitride nanosheets (g-C4 N3 and g-C3 N4 ) is proposed as a strategy for high-capacity and electrocatalytically switchable hydrogen storage. Using first-principle calculations, we found that the adsorption energy of H2 molecules on graphitic carbon nitride nanosheets is dramatically enhanced by injecting extra electrons into the adsorbent. At full hydrogen coverage, the negatively charged graphitic carbon nitride achieves storage capacities up to 6-7 wt %. In contrast to other hydrogen storage approaches, the storage/release occurs spontaneously once extra electrons are introduced or removed, and these processes can be simply controlled by switching on/off the charging voltage. Therefore, this approach promises both facile reversibility and tunable kinetics without the need of specific catalysts. Importantly, g-C4 N3 has good electrical conductivity and high electron mobility, which can be a very good candidate for electron injection/release. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage materials. 13. Development and Validation of a Slurry Model for Chemical Hydrogen Storage in Fuel Cell Applications SciTech Connect Brooks, Kriston P.; Pires, Richard P.; Simmons, Kevin L. 2014-07-25 The US Department of Energy's (DOE) Hydrogen Storage Engineering Center of Excellence (HSECoE) is developing models for hydrogen storage systems for fuel cell-based light duty vehicle applications for a variety of promising materials. These transient models simulate the performance of the storage system for comparison to the DOE’s Technical Targets and a set of four drive cycles. The purpose of this research is to describe the models developed for slurry-based chemical hydrogen storage materials. The storage systems of both a representative exothermic system based on ammonia borane and endothermic system based on alane were developed and modeled in Simulink®. Once complete the reactor and radiator components of the model were validated with experimental data. The model was then run using a highway cycle, an aggressive cycle, cold-start cycle and hot drive cycle. The system design was adjusted to meet these drive cycles. A sensitivity analysis was then performed to identify the range of material properties where these DOE targets and drive cycles could be met. Materials with a heat of reaction greater than 11 kJ/mol H2 generated and a slurry hydrogen capacity of greater than 11.4% will meet the on-board efficiency and gravimetric capacity targets, respectively. 14. A multidisciplinary combinatorial approach for tuning promising hydrogen storage materials towards automotive applications. PubMed Amieiro-Fonseca, A; Ellis, S R; Nuttall, C J; Hayden, B E; Guerin, S; Purdy, G; Soulié, J P; Callear, S K; Culligan, S D; David, W I F; Edwards, P P; Jones, M O; Johnson, S R; Pohl, A H 2011-01-01 HyStorM is a multidisciplinary hydrogen-storage project aiming to synthesise and tune materials hydrogen storage properties for automotive applications. Firstly, unique high-throughput combinatorial thin-film technologies are used to screen materials' hydrogen storage properties. Then promising thin-film candidate compositions are synthesised and examined in the bulk. In this paper, we report on our results within the ternary compositions Mg-Ti-B and Ca-Ti-B. Primary screening of the Mg-Ti-B ternary identified a high capacity hotspot corresponding to Mg0.36Ti0.06B0.58, with 10.6 wt% H2 capacity. Partial reversibility has been observed for this material in the thin-film. Bulk Ti-doped Mg(BH4)2 composites show rehydrogenation to MgH2 under the conditions used. The synthesised thin-film Ca-Ti-B ternary showed only low hydrogen storage capacities. In the bulk, Ti-doping experiments on Ca(BH4)2 demonstrated reversible storage capacities up to 5.9 wt% H2. Further characterisation experiments are required to decipher the role of the Ti-dopant in these systems in both films and in the bulk. 15. NaBH4 in "Graphene Wrapper:" Significantly Enhanced Hydrogen Storage Capacity and Regenerability through Nanoencapsulation. PubMed Chong, Lina; Zeng, Xiaoqin; Ding, Wenjiang; Liu, Di-Jia; Zou, Jianxin 2015-09-01 A new high-capacity reversible hydrogen-storage material synthesized by the encapsulation of NaBH4 nanoparticles in graphene is reported. This approach effectively prevents phase agglomeration or separation during successive H2 discharge/recharge processes and enables rapid H2 uptake and release in NaBH4 under mild conditions. The strategy advanced here paves a new way for application in energy generation and storage. 16. Progress on first-principles-based materials design for hydrogen storage PubMed Central Park, Noejung; Choi, Keunsu; Hwang, Jeongwoon; Kim, Dong Wook; Kim, Dong Ok; Ihm, Jisoon 2012-01-01 This article briefly summarizes the research activities in the field of hydrogen storage in sorbent materials and reports our recent works and future directions for the design of such materials. Distinct features of sorption-based hydrogen storage methods are described compared with metal hydrides and complex chemical hydrides. We classify the studies of hydrogen sorbent materials in terms of two key technical issues: (i) constructing stable framework structures with high porosity, and (ii) increasing the binding affinity of hydrogen molecules to surfaces beyond the usual van der Waals interaction. The recent development of reticular chemistry is summarized as a means for addressing the first issue. Theoretical studies focus mainly on the second issue and can be grouped into three classes according to the underlying interaction mechanism: electrostatic interactions based on alkaline cations, Kubas interactions with open transition metals, and orbital interactions involving Ca and other nontransitional metals. Hierarchical computational methods to enable the theoretical predictions are explained, from ab initio studies to molecular dynamics simulations using force field parameters. We also discuss the actual delivery amount of stored hydrogen, which depends on the charging and discharging conditions. The usefulness and practical significance of the hydrogen spillover mechanism in increasing the storage capacity are presented as well. PMID:23161910 17. Progress on first-principles-based materials design for hydrogen storage. PubMed Park, Noejung; Choi, Keunsu; Hwang, Jeongwoon; Kim, Dong Wook; Kim, Dong Ok; Ihm, Jisoon 2012-12-01 This article briefly summarizes the research activities in the field of hydrogen storage in sorbent materials and reports our recent works and future directions for the design of such materials. Distinct features of sorption-based hydrogen storage methods are described compared with metal hydrides and complex chemical hydrides. We classify the studies of hydrogen sorbent materials in terms of two key technical issues: (i) constructing stable framework structures with high porosity, and (ii) increasing the binding affinity of hydrogen molecules to surfaces beyond the usual van der Waals interaction. The recent development of reticular chemistry is summarized as a means for addressing the first issue. Theoretical studies focus mainly on the second issue and can be grouped into three classes according to the underlying interaction mechanism: electrostatic interactions based on alkaline cations, Kubas interactions with open transition metals, and orbital interactions involving Ca and other nontransitional metals. Hierarchical computational methods to enable the theoretical predictions are explained, from ab initio studies to molecular dynamics simulations using force field parameters. We also discuss the actual delivery amount of stored hydrogen, which depends on the charging and discharging conditions. The usefulness and practical significance of the hydrogen spillover mechanism in increasing the storage capacity are presented as well. 18. REVERSIBLE HYDROGEN STORAGE IN A LiBH{sub 4}-C{sub 60} NANOCOMPOSITE SciTech Connect Teprovich, J.; Zidan, R.; Peters, B.; Wheeler, J. 2013-08-06 Reversible hydrogen storage in a LiBH{sub 4}:C{sub 60} nanocomposite (70:30 wt. %) synthesized by solvent-assisted mixing has been demonstrated. During the solvent-assisted mixing and nanocomposite formation, a chemical reaction occurs in which the C{sub 60} cages are significantly modified by polymerization as well as by hydrogenation (fullerane formation) in the presence of LiBH{sub 4}. We have determined that two distinct hydrogen desorption events are observed upon rehydrogenation of the material, which are attributed to the reversible formation of a fullerane (C{sub 60}H{sub x}) as well as a LiBH4 species. This system is unique in that the carbon species (C{sub 60}) actively participates in the hydrogen storage process which differs from the common practice of melt infiltration of high surface area carbon materials with LiBH{sub 4} (nanoconfinment effect). This nanocomposite demonstrated good reversible hydrogen storage properties as well as the ability to absorb hydrogen under mild conditions (pressures as low as 10 bar H{sub 2} or temperatures as low as 150°C). The nanocomposite was characterized by TGA-RGA, DSC, XRD, LDI-TOF-MS, FTIR, 1H NMR, and APPI MS. 19. Robustness and Thermophysical Properties of MOF-5: A Prototypical Hydrogen Storage Material NASA Astrophysics Data System (ADS) Ming, Yang Metal-organic frameworks (MOFs) are an emerging class of microporous, crystalline materials with potential applications in the capture, storage, and separation of gasses. Of the many known MOFs, the compound known as MOF-5 has attracted considerable attention due to its ability to store gaseous fuels at low pressure with high densities. However, low thermal conductivity and limited robustness upon exposure to water and other reactive species are two challenges which limit the application of MOF-5; similar issues plague several other MOFs. The focus of this dissertation is to understand and overcome these shortcomings through detailed experimental and computational characterization of the prototype compound, MOF-5. The insight provided by this study regarding the properties of MOFs will aid in the transition of these materials from lab bench to applications. Improvements to the thermal conductivity of MOF-5 are demonstrated using densified pellets consisting of a physical mixture of MOF-5 and expanded natural graphite (ENG). The high-aspect ratio of ENG particles, combined with uni-axial compression, results in anisotropic microstructural and thermal transport properties in the pellets. Perpendicular to the pressing direction the thermal conductivity was observed to be two to four times higher than in the orthogonal direction. We further demonstrate that this anisotropy can be exploited to enhance conductivity along a preferred direction in the pellets by altering the pellet processing conditions. We conclude that the low thermal conductivity typical of MOFs can be improved using a judicious combination of second phase additions and processing techniques. Regarding robustness, we first quantify experimentally the impact of humid air exposure on the properties of MOF-5 as a function of exposure time, humidity level, and morphology (i.e., powders vs. pellets). For humidity levels below 50% only minor degradation is observed for exposure times up to several hours. In 20. Metal-organic frameworks for the storage and delivery of biologically active hydrogen sulfide SciTech Connect Allan, Phoebe K; Wheatley, Paul S; Aldous, David; Mohideen, M Infas; Tang, Chiu; Hriljac, Joseph A; Megson, Ian L; Chapman, Karena W; De Weireld, Guy; Vaesen, Sebastian; Morris, Russell E 2012-04-02 Hydrogen sulfide is an extremely toxic gas that is also of great interest for biological applications when delivered in the correct amount and at the desired rate. Here we show that the highly porous metal-organic frameworks with the CPO-27 structure can bind the hydrogen sulfide relatively strongly, allowing the storage of the gas for at least several months. Delivered gas is biologically active in preliminary vasodilation studies of porcine arteries, and the structure of the hydrogen sulfide molecules inside the framework has been elucidated using a combination of powder X-ray diffraction and pair distribution function analysis. 1. Titanium-decorated graphene for high-capacity hydrogen storage studied by density functional simulations NASA Astrophysics Data System (ADS) Liu, Yali; Ren, Ling; He, Yao; Cheng, Hai-Ping 2010-10-01 We present results of density functional theory (DFT) calculations of the adsorption of hydrogen molecules on Ti-decorated graphene. Our results indicate that the binding energies of molecular hydrogen on Ti-decorated graphene can be dramatically enhanced to 0.23-0.60 eV. The hybridization of the Ti 3d orbitals with the H2 σ and σ* orbitals plays a central role in the enhanced binding. There is also a contribution from the attractive interaction between the surface dipole and the dipole of polarized H2. It can be expected that Ti-decorated graphene could be considered as a potential high-capacity hydrogen storage medium. 2. Hydrogen storage materials: room-temperature wet-chemistry approach toward mixed-metal borohydrides. PubMed Jaroń, Tomasz; Orłowski, Piotr A; Wegner, Wojciech; Fijałkowski, Karol J; Leszczyński, Piotr J; Grochala, Wojciech 2015-01-19 The poor kinetics of hydrogen evolution and the irreversibility of the hydrogen discharge hamper the use of transition metal borohydrides as hydrogen storage materials, and the drawbacks of current synthetic methods obstruct the exploration of these systems. A wet-chemistry approach, which is based on solvent-mediated metathesis reactions of precursors containing bulky organic cations and weakly coordinating anions, leads to mixed-metal borohydrides that contain only a small amount of "dead mass". The applicability of this method is exemplified by Li[Zn2(BH4)5] and M[Zn(BH4)3] salts (M=Na, K), and its extension to other systems is discussed. 3. Characterization of the surface changes during the activation of erbium/erbium oxide for hydrogen storage. SciTech Connect Zavadil, Kevin Robert; Snow, Clark Sheldon; Brumbach, Michael Todd 2010-09-01 Erbium is known to effectively load with hydrogen when held at high temperature in a hydrogen atmosphere. To make the storage of hydrogen kinetically feasible, a thermal activation step is required. Activation is a routine practice, but very little is known about the physical, chemical, and/or electronic processes that occur during Activation. This work presents in situ characterization of erbium Activation using variable energy photoelectron spectroscopy at various stages of the Activation process. Modification of the passive surface oxide plays a significant role in Activation. The chemical and electronic changes observed from core-level and valence band spectra will be discussed along with corroborating ion scattering spectroscopy measurements. 4. Electron-beam-induced information storage in hydrogenated amorphous silicon device DOEpatents Yacobi, Ben G. 1986-01-01 A method for recording and storing information in a hydrogenated amorphous silicon device, comprising: depositing hydrogenated amorphous silicon on a substrate to form a charge-collection device; and generating defects in the hydrogenated amorphous silicon device, wherein the defects act as recombination centers that reduce the lifetime of carriers, thereby reducing charge-collection efficiency; and thus in the charge-collection mode of scanning probe instruments, regions of the hydrogenated amorphous silicon device that contain the defects appear darker in comparison to regions of the device that do not contain the defects, leading to a contrast formation for pattern recognition and information storage, in the device, which darkened areas can be restored to their original charge-collection efficiency by heating the hydrogenated amorphous silicon to a temperature of about 100.degree. C. to 250.degree. C. for a sufficient period of time to provide for such restoration. 5. DFT STUDY OF HYDROGEN STORAGE ON Li- AND Na-DOPED C59B HETEROFULLERENE NASA Astrophysics Data System (ADS) Zahedi, Ehsan; Mozaffari, Majid 2014-05-01 Effect of light alkali metal (Li and Na) decorated on the C59B heterofullerene for hydrogen storage is considered using DFT-MPW1PW91 method. Results show that Li and Na atoms strongly prefer to adsorb on top of five-member and six-member ring where a carbon atom is replaced by a boron atom. Significant charge transfer from the alkali metal to the C59B compensates for the electron deficiency of C59B and makes the latter aromatic in nature. Corrected binding energies of hydrogen molecule on the alkali-doped C59B using counterpoise method, structural properties and NBO analysis indicate that first hydrogen molecule is adsorbed physically and does not support minimal conditions of DOE requirement. Finally, positive values of binding energies for the adsorption of a second hydrogen molecule show that alkali doped C59B are capable of storing a maximum of one hydrogen molecule. 6. Carbide-Derived Carbons with Tunable Porosity Optimized for Hydrogen Storage SciTech Connect Fisher, John E.; Gogotsi, Yury; Yildirim, Taner 2010-01-07 On-board hydrogen storage is a key requirement for fuel cell-powered cars and trucks. Porous carbon-based materials can in principle adsorb more hydrogen per unit weight at room temperature than liquid hydrogen at -176 oC. Achieving this goal requires interconnected pores with very high internal surface area, and binding energies between hydrogen and carbon significantly enhanced relative to H2 on graphite. In this project a systematic study of carbide-derived carbons, a novel form of porous carbon, was carried out to discover a high-performance hydrogen sorption material to meet the goal. In the event we were unable to improve on the state of the art in terms of stored hydrogen per unit weight, having encountered the same fundamental limit of all porous carbons: the very weak interaction between H2 and the carbon surface. On the other hand we did discover several strategies to improve storage capacity on a volume basis, which should be applicable to other forms of porous carbon. Further discoveries with potentially broader impacts include • Proof that storage performance is not directly related to pore surface area, as had been previously claimed. Small pores (< 1.5 nm) are much more effective in storing hydrogen than larger ones, such that many materials with large total surface areas are sub-par performers. • Established that the distribution of pore sizes can be controlled during CDC synthesis, which opens the possibility of developing high performance materials within a common family while targeting widely disparate applications. Examples being actively pursued with other funding sources include methane storage, electrode materials for batteries and supercapacitors with record high specific capacitance, and perm-selective membranes which bind cytokines for control of infections and possibly hemodialysis filters. 7. Hydrogen Energy Storage and Power-to-Gas: Establishing Criteria for Successful Business Cases SciTech Connect Eichman, Joshua; Melaina, Marc 2015-10-27 As the electric sector evolves and increasing amounts of variable generation are installed on the system, there are greater needs for system flexibility, sufficient capacity and greater concern for overgeneration. As a result there is growing interest in exploring the role of energy storage and demand response technologies to support grid needs. Hydrogen is a versatile feedstock that can be used in a variety of applications including chemical and industrial processes, as well as a transportation fuel and heating fuel. Traditionally, hydrogen technologies focus on providing services to a single sector; however, participating in multiple sectors has the potential to provide benefits to each sector and increase the revenue for hydrogen technologies. The goal of this work is to explore promising system configurations for hydrogen systems and the conditions that will make for successful business cases in a renewable, low-carbon future. Current electricity market data, electric and gas infrastructure data and credit and incentive information are used to perform a techno-economic analysis to identify promising criteria and locations for successful hydrogen energy storage and power-to-gas projects. Infrastructure data will be assessed using geographic information system applications. An operation optimization model is used to co-optimizes participation in energy and ancillary service markets as well as the sale of hydrogen. From previous work we recognize the great opportunity that energy storage and power-to-gas but there is a lack of information about the economic favorability of such systems. This work explores criteria for selecting locations and compares the system cost and potential revenue to establish competitiveness for a variety of equipment configurations. Hydrogen technologies offer unique system flexibility that can enable interactions between multiple energy sectors including electric, transport, heating fuel and industrial. Previous research established that 8. Early warning indicators for challenges in underground coal storage. PubMed Sipilä, Juha; Auerkari, Pertti; Holmström, Stefan; Vela, Iris 2014-12-01 Early warning or leading indicators are discussed for unexpected incidences in case of large-scale underground coal storage at a power plant. The experience is compared with above-ground stockpiles for which established procedures are available but where access for prevention and mitigation are much easier. It is suggested that while the explicit organization, procedures, and the general safety systems aim to provide the targeted levels of performance for the storage, representing new technology without much precedence elsewhere in the world, the extensive experience and tacit knowledge from above-ground open and closed storage systems can help to prepare for and to prevent unwanted incidents in the underground storage. This kind of experience has been also found useful for developing the leading or early warning indicators for underground storage. Examples are given on observed autoignition and freezing of coal in the storage silos, and on occupational hazards. Selection of the leading indicators needs to consider the specific features of the unique underground facility. PMID:25196594 9. V1.6 Development of Advanced Manufacturing Technologies for Low Cost Hydrogen Storage Vessels SciTech Connect Leavitt, Mark; Lam, Patrick; Nelson, Karl M.; johnson, Brice A.; Johnson, Kenneth I.; Alvine, Kyle J.; Ruiz, Antonio; Adams, Jesse 2012-10-01 The goal of this project is to develop an innovative manufacturing process for Type IV high-pressure hydrogen storage vessels, with the intent to significantly lower manufacturing costs. Part of the development is to integrate the features of high precision AFP and commercial FW. Evaluation of an alternative fiber to replace a portion of the baseline fiber will help to reduce costs further. 10. NREL Develops Accelerated Sample Activation Process for Hydrogen Storage Materials (Fact Sheet) SciTech Connect Not Available 2010-12-01 This fact sheet describes NREL's accomplishments in developing a new sample activation process that reduces the time to prepare samples for measurement of hydrogen storage from several days to five minutes and provides more uniform samples. Work was performed by NREL's Chemical and Materials Science Center. 11. Metalized T graphene: A reversible hydrogen storage material at room temperature SciTech Connect Ye, Xiao-Juan; Zhong, Wei E-mail: wzhong@nju.edu.cn; Du, You-Wei; Liu, Chun-Sheng E-mail: wzhong@nju.edu.cn; Zeng, Zhi 2014-09-21 Lithium (Li)-decorated graphene is a promising hydrogen storage medium due to its high capacity. However, homogeneous mono-layer coating graphene with lithium atoms is metastable and the lithium atoms would cluster on the surface, resulting in the poor reversibility. Using van der Waals-corrected density functional theory, we demonstrated that lithium atoms can be homogeneously dispersed on T graphene due to a nonuniform charge distribution in T graphene and strong hybridizations between the C-2p and Li-2p orbitals. Thus, Li atoms are not likely to form clusters, indicating a good reversible hydrogen storage. Both the polarization mechanism and the orbital hybridizations contribute to the adsorption of hydrogen molecules (storage capacity of 7.7 wt. %) with an optimal adsorption energy of 0.19 eV/H₂. The adsorption/desorption of H₂ at ambient temperature and pressure is also discussed. Our results can serve as a guide in the design of new hydrogen storage materials based on non-hexagonal graphenes. 12. Analysis of Cost-Effective Off-Board Hydrogen Storage and Refueling Stations SciTech Connect Ted Barnes; William Liss 2008-11-14 This report highlights design and component selection considerations for compressed gas hydrogen fueling stations operating at 5000 psig or 350 bar. The primary focus is on options for compression and storage – in terms of practical equipment options as well as various system configurations and how they influence delivery performance and station economics. 13. Lithium-decorated oxidized graphyne for hydrogen storage by first principles study SciTech Connect Yan, Zeyu; Wang, Lang; Cheng, Julong; Huang, Libei; Zhu, Chao; Chen, Chi; Miao, Ling Jiang, Jianjun 2014-11-07 The geometric stability and hydrogen storage capacity of Li decorated oxidized γ-graphyne are studied based on the first-principles calculations. It is found that oxygen atoms trend to bond with acetylenic carbons and form C=O double bonds on both sides of graphyne. The binding energy of single Li atom on oxidized graphyne is 3.29 eV, owning to the strong interaction between Li atom and O atom. Meanwhile, the dispersion of Li is stable even under a relatively high density. One attached Li atom can at least adsorb six hydrogen molecules around. Benefitting from the porous structure of graphyne and the high attached Li density, a maximum hydrogen storage density 12.03 wt. % is achieved with four Li atoms in graphyne cell. The corresponding average binding energy is 0.24 eV/H{sub 2}, which is suitable for reversible storage. These results indicate that Li decorated graphyne can serve as a promising hydrogen storage material. 14. Physics of Hydrogen Storage in Metal-Hydrides NASA Astrophysics Data System (ADS) Abdelfattah-Zidan, Ragaiy Physical aspects of the hydrogenation-dehydrogenation mechanisms of metal-metal hydride systems were examined. Experimental investigation was conducted for magnesium hydride as a case study. Theoretical analysis and computational study were carried out. The kinetics of hydrogenation-dehydrogenation of traditionally prepared Mg-MgH_2 and chemically synthesized Mg-MgH_2 were experimentally investigated. A detailed investigation was carried out to determine the reasons for the improved performance of a chemically synthesized Mg-MgH _2 previously reported by Bogdanovic and co-workers. A scanning electron microscope was used to examine the surface morphology of the samples. The surface of chemically prepared samples appeared to be covered with micro-spheroidal beads ranging in radius between 0.5 μm and 0.05 μm formed in a fractal-like configuration. Theoretical analysis indicated that the unusual surface structure of the chemically prepared samples could be responsible for the rapid uptake and release of hydrogen. The uptake and release enhancement is believed to be partially due to the substantial increase in the surface area and partially due fast diffusion into the smaller particles. The effect of the addition of nickel to the surface was also investigated. Theoretical analysis was carried out. Models for the process at the surface as well as in the bulk were developed. Diffusion equation was examined taking into account the diffusion coefficient being function of concentration. A non-linear differential equation resulted for this case. The differential equation was numerically solved. 15. Recommended volumetric capacity definitions and protocols for accurate, standardized and unambiguous metrics for hydrogen storage materials NASA Astrophysics Data System (ADS) Parilla, Philip A.; Gross, Karl; Hurst, Katherine; Gennett, Thomas 2016-03-01 The ultimate goal of the hydrogen economy is the development of hydrogen storage systems that meet or exceed the US DOE's goals for onboard storage in hydrogen-powered vehicles. In order to develop new materials to meet these goals, it is extremely critical to accurately, uniformly and precisely measure materials' properties relevant to the specific goals. Without this assurance, such measurements are not reliable and, therefore, do not provide a benefit toward the work at hand. In particular, capacity measurements for hydrogen storage materials must be based on valid and accurate results to ensure proper identification of promising materials for further development. Volumetric capacity determinations are becoming increasingly important for identifying promising materials, yet there exists controversy on how such determinations are made and whether such determinations are valid due to differing methodologies to count the hydrogen content. These issues are discussed herein, and we show mathematically that capacity determinations can be made rigorously and unambiguously if the constituent volumes are well defined and measurable in practice. It is widely accepted that this occurs for excess capacity determinations and we show here that this can happen for the total capacity determination. Because the adsorption volume is undefined, the absolute capacity determination remains imprecise. Furthermore, we show that there is a direct relationship between determining the respective capacities and the calibration constants used for the manometric and gravimetric techniques. Several suggested volumetric capacity figure-of-merits are defined, discussed and reporting requirements recommended. Finally, an example is provided to illustrate these protocols and concepts. 16. Catalyzed light hydride nanomaterials embedded in a micro-channels hydrogen storage container. PubMed Dehouche, Zahir; Peretti, Hernán A; Yoo, Yeong; Belkacemi, Khaled; Goyette, Jacques 2009-01-01 Activated alloys synthesized by arc-melting were examined as catalysts for improving the hydrogen sorption characteristics of nanostructured magnesium hydride, proposed as a reversible hydrogen storage material. The MgH(2)-catalyst absorbing materials were prepared by ball milling of pure MgH(2) with hydrided Zr(47)Ni(53), Zr(9)Ni(11), and other alloys investigated. The nanostructured MgH(2)-intermetallic systems were tested at 250 degrees C and catalyst addition of eutectoid Zr(47)Ni(53) resulted in the fastest desorption time and highest initial desorption rate. The catalyzed Mg-hydride with activated Zr(9)Ni(11) and Zr(7)Ni(10) phases showed fast desorption kinetics. Moreover, the results demonstrated that the composition of dispersed Zr(x)Ni(y)catalysts has a strong influence on the amount of accumulated hydrogen and desorption rate of Mg-nanocomposite. Part two covers advanced micro-channels hydrogen storage module design based on the results of semi-empirical computer simulations of heat and mass transfers in the container. The micro-channels reservoir concept offers many advantages over the conventional metal hydride hydrogen storage system. It is a micro-structured system that can pack a lot of power into a small space and dissipate effectively the heat of the sorption reactions. This review summarizes recent patents related to CNTS. 17. The H60Si6C54 heterofullerene as high-capacity hydrogen storage medium NASA Astrophysics Data System (ADS) Yong, Yongliang; Zhou, Qingxiao; Li, Xiaohong; Lv, Shijie 2016-07-01 With the great success in Si atoms doped C60 fullerene and the well-established methods for synthesis of hydrogenated carbon fullerenes, this leads naturally to wonder whether Si-doped fullerenes are possible for special applications such as hydrogen storage. Here by using first-principles calculations, we design a novel high-capacity hydrogen storage material, H60Si6C54 heterofullerene, and confirm its geometric stability. It is found that the H60Si6C54 heterofullerene has a large HOMO-LUMO gap and a high symmetry, indicating it is high chemically stable. Further, our finite temperature simulations indicate that the H60Si6C54 heterofullerene is thermally stable at 300 K. H2 molecules would enter into the cage from the Si-hexagon ring because of lower energy barrier. Through our calculation, a maximum of 21 H2 molecules can be stored inside the H60Si6C54 cage in molecular form, leading to a gravimetric density of 11.11 wt% for 21H2@H60Si6C54 system, which suggests that the hydrogenated Si6C54 heterofullerene could be suitable as a high-capacity hydrogen storage material. 18. Curvature and ionization-induced reversible hydrogen storage in metalized hexagonal B36. PubMed Liu, Chun-Sheng; Wang, Xiangfu; Ye, Xiao-Juan; Yan, Xiaohong; Zeng, Zhi 2014-11-21 The synthesis of quasiplanar boron clusters (B36) with a central hexagonal hole provides the first experimental evidence that a single-atomic-layer borophene with hexagonal vacancies is potentially viable [Z. Piazza, H. Hu, W. Li, Y. Zhao, J. Li, and L. S. Wang, Nat. Commun. 5, 3113 (2014)]. However, owing to the hexagonal holes, tunning the electronic and physical properties of B36 through chemical modifications is not fully understood. Based on (van der Waals corrected-) density functional theory, we show that Li adsorbed on B36 and B36 (-) clusters can serve as reversible hydrogen storage media. The present results indicate that the curvature and ionization of substrates can enhance the bond strength of Li due to the energetically favorable B 2p-Li 2p orbitals hybridization. Both the polarization mechanism and the orbital hybridization between H-s orbitals and Li-2s2p orbitals contribute to the adsorption of H2 molecules and the resulting adsorption energy lies between the physisorbed and chemisorbed states. Interestingly, the number of H2 in the hydrogen storage medium can be measured by the appearance of the negative differential resistance behavior at different bias voltage regions. Furthermore, the cluster-assembled hydrogen storage materials constructed by metalized B36 clusters do not cause a decrease in the number of adsorbed hydrogen molecules per Li. The system reported here is favorable for the reversible hydrogen adsorption/desorption at ambient conditions. PMID:25416890 19. Development and Demonstration of Insulated Pressure Vessels for Vehicular Hydrogen Storage SciTech Connect Berry, G D; Aceves, S M 2004-02-26 This paper describes the development of an alternative technology for vehicular storage of hydrogen. Insulated pressure vessels are cryogenic-capable pressure vessels that can accept cryogenic liquid fuel, cryogenic compressed gas or compressed gas at ambient temperature. Insulated pressure vessels offer advantages over alternative hydrogen storage technologies. Insulated pressure vessels are more compact and less expensive than compressed hydrogen vessels. They have lower evaporative losses and lower energy requirement for fuel liquefaction than liquid hydrogen tanks, and they are lighter than hydrides. The work described in this paper is directed at verifying that insulated pressure vessels can be used safely for vehicular hydrogen storage. The paper describes multiple tests and analyses that have been conducted to evaluate the safety of insulated pressure vessels. Insulated pressure vessels have been subjected to multiple DOT, ISO and SAE certification tests, and the vessels have always been successful in meeting the passing criteria for the different tests. A draft procedure for insulated pressure vessel certification has been generated to assist in a future commercialization of this technology. Ongoing work includes the demonstration of this technology in a vehicle. 20. Technical assessment of compressed hydrogen storage tank systems for automotive applications. SciTech Connect Hua, T. Q.; Ahluwalia, R. K.; Peng, J. K.; Kromer, M.; Lasher, S.; McKenney, K.; Law, K.; Sinha, J. 2011-02-09 The performance and cost of compressed hydrogen storage tank systems has been assessed and compared to the U.S. Department of Energy (DOE) 2010, 2015, and ultimate targets for automotive applications. The on-board performance and high-volume manufacturing cost were determined for compressed hydrogen tanks with design pressures of 350 bar ({approx}5000 psi) and 700 bar ({approx}10,000 psi) capable of storing 5.6 kg of usable hydrogen. The off-board performance and cost of delivering compressed hydrogen was determined for hydrogen produced by central steam methane reforming (SMR). The main conclusions of the assessment are that the 350-bar compressed storage system has the potential to meet the 2010 and 2015 targets for system gravimetric capacity but will not likely meet any of the system targets for volumetric capacity or cost, given our base case assumptions. The 700-bar compressed storage system has the potential to meet only the 2010 target for system gravimetric capacity and is not likely to meet any of the system targets for volumetric capacity or cost, despite the fact that its volumetric capacity is much higher than that of the 350-bar system. Both the 350-bar and 700-bar systems come close to meeting the Well-to-Tank (WTT) efficiency target, but fall short by about 5%. These results are summarized. 1. Curvature and ionization-induced reversible hydrogen storage in metalized hexagonal B36. PubMed Liu, Chun-Sheng; Wang, Xiangfu; Ye, Xiao-Juan; Yan, Xiaohong; Zeng, Zhi 2014-11-21 The synthesis of quasiplanar boron clusters (B36) with a central hexagonal hole provides the first experimental evidence that a single-atomic-layer borophene with hexagonal vacancies is potentially viable [Z. Piazza, H. Hu, W. Li, Y. Zhao, J. Li, and L. S. Wang, Nat. Commun. 5, 3113 (2014)]. However, owing to the hexagonal holes, tunning the electronic and physical properties of B36 through chemical modifications is not fully understood. Based on (van der Waals corrected-) density functional theory, we show that Li adsorbed on B36 and B36 (-) clusters can serve as reversible hydrogen storage media. The present results indicate that the curvature and ionization of substrates can enhance the bond strength of Li due to the energetically favorable B 2p-Li 2p orbitals hybridization. Both the polarization mechanism and the orbital hybridization between H-s orbitals and Li-2s2p orbitals contribute to the adsorption of H2 molecules and the resulting adsorption energy lies between the physisorbed and chemisorbed states. Interestingly, the number of H2 in the hydrogen storage medium can be measured by the appearance of the negative differential resistance behavior at different bias voltage regions. Furthermore, the cluster-assembled hydrogen storage materials constructed by metalized B36 clusters do not cause a decrease in the number of adsorbed hydrogen molecules per Li. The system reported here is favorable for the reversible hydrogen adsorption/desorption at ambient conditions. 2. The Role of Water in the Storage of Hydrogen in Metals NASA Technical Reports Server (NTRS) Hampton, Michael D.; Lomness, Janice K.; Giannuzzi, Lucille A. 2001-01-01 One major problem with the use of hydrogen is safe and efficient storage. In the pure form, bulky and heavy containers are required greatly reducing the efficiency of its use. Safety is also a great concern. Storage of hydrogen in the form of a metal hydride offers distinct advantages both in terms of volumetric efficiency and in terms of safety. As a result, an enormous amount of research is currently being done on metal-hydrogen systems. Practical application of these systems to storage of hydrogen can only occur when they are very well understood. In this paper, the preliminary results of a study of the surfaces of magnesium nickel alloys will be presented. Alloys that have been rendered totally unreactive with hydrogen as well as those that have been activated with liquid water and with water vapor were studied. Data obtained from XPS (X-ray Photoelectron Spectrometer) analysis, with samples held in vacuum for the shortest possible time to minimize the hydroxide degradation will be presented. Furthermore, TEM data on samples prepared in a new way that largely protects the surface from the high vacuum will be discussed. 3. A Micro-fabricated Hydrogen Storage Module with Sub-atmospheric Activation and Durability in Air Exposure. PubMed Shan, Xi; Payer, Joe H; Wainright, Jesse S; Dudik, Laurie 2011-01-15 The objective of this work was to develop a hydrogen storage module for onboard electrical power sources suitable for use in micro power systems and micro-electro-mechanical systems (MEMS). Hydrogen storage materials were developed as thin-film inks to be compatible with an integrated manufacturing process. Important design aspects were (a) ready activation at sub-atmospheric hydrogen pressure and room temperature and (b) durability, i.e. capable of hundreds of absorption/desorption cycles and resistance to deactivation on exposure to air. Inks with palladium-treated intermetallic hydrogen storage alloys were developed and are shown here to be compatible with a thin-film micro-fabrication process. These hydrogen storage modules absorb hydrogen readily at atmospheric pressure, and the absorption/desorption rates remained fast even after the ink was exposed to air for 47 weeks. 4. A life cycle cost analysis framework for geologic storage of hydrogen : a scenario analysis. SciTech Connect Kobos, Peter Holmes; Lord, Anna Snider; Borns, David James 2010-10-01 The U.S. Department of Energy has an interest in large scale hydrogen geostorage, which would offer substantial buffer capacity to meet possible disruptions in supply. Geostorage options being considered are salt caverns, depleted oil/gas reservoirs, aquifers and potentially hard rock cavrns. DOE has an interest in assessing the geological, geomechanical and economic viability for these types of hydrogen storage options. This study has developed an ecocomic analysis methodology to address costs entailed in developing and operating an underground geologic storage facility. This year the tool was updated specifically to (1) a version that is fully arrayed such that all four types of geologic storage options can be assessed at the same time, (2) incorporate specific scenarios illustrating the model's capability, and (3) incorporate more accurate model input assumptions for the wells and storage site modules. Drawing from the knowledge gained in the underground large scale geostorage options for natural gas and petroleum in the U.S. and from the potential to store relatively large volumes of CO{sub 2} in geological formations, the hydrogen storage assessment modeling will continue to build on these strengths while maintaining modeling transparency such that other modeling efforts may draw from this project. 5. General Motors: Final Report for Hydrogen Storage Engineering Center of Excellence SciTech Connect Cai, Mei; Chakraborty, Amlan; Hou, Peter; Kaisare, Niklet; Jorgensen, Scott; Kumar, Sudarshan; Li, Changpeng; Ortmann, Jerome; Raju, M.; Vadivelu, S. Kumar 2015-06-30 As part of the HSECoE team, the GM team built system models and detailed transport models for on-board hydrogen storage systems using metal hydrides and adsorbent materials. Detailed transport models have been developed for both the metal hydride and adsorbent systems with a focus on optimization of heat exchanger designs with the objective of minimizing the heat exchanger mass. We also performed work in collaboration with our partners on storage media structuring and enhancement studies for the metal hydride and adsorbent materials. Since the hydrogen storage materials are generally characterized by low density and low thermal conductivity, we conducted experiments to form pellets and add thermal conductivity enhancers to the storage material, and to improve cycling stability and durability of the metal hydride and adsorbent materials. Refueling of a MOF-5 pellet with cryogenic hydrogen was studied by developing a detailed two-dimensional axisymmetric COMSOL® model of the process. The effects of pellet permeability, thermal conductivity, and thermal conductivity enhancers were investigated. Our key area of focus has been on designing and building a cryo-adsorption vessel for validation of cryo-adsorption models. The 3-L cryogenic tank was used to study the fast fill and discharge dynamics of a cryo-adsorbent storage system, both experimentally and numerically. 6. Retention property of deuterium for fuel recovery in divertor by using hydrogen storage material NASA Astrophysics Data System (ADS) Mera, Saori; Tonegawa, Akira; Matsumura, Yoshihito; Sato, Kohnosuke; Kawamura, Kazutaka 2014-10-01 Magnetic confinement fusion reactor by using Deuterium and Tritium of hydrogen isotope as fuels is suggested as one of the future energy source. Most fuels don't react and are exhausted out of fusion reactor. Especially, Tritium is radioisotope and rarely exists in nature, so fuels recovery is necessary. This poster presentation will explain about research new fuel recovery method by using hydrogen storage materials in divertor simulator TPD-Sheet IV. Samples are tungsten coated with titanium; tungsten of various thickness, and titanium films deposited by ion plating on tungsten substrates. The sample surface temperature is measured by radiation thermometer. Retention property of deuterium after deuterium plasma irradiation was examined with thermal desorption spectroscopy (TDS). As a result, the TDS measurement shows that deuterium is retained in titanium. Therefore, Titanium as a hydrogen storage material expects to be possible to use separating and recovering fuel particles in divertor. 7. Yttrium-dispersed B80 fullerenes: Promising materials for hydrogen storage NASA Astrophysics Data System (ADS) Wu, W. W.; Tian, Z. Y.; Dong, S. L. 2015-03-01 We report a first-principles study, which predicts that a single yttrium atom decorated on B80 fullerenes can maximally hold up six H2 molecules with an average binding energy of -0.55 \\text{eV}/\\text{H}2 . The analysis with 12 Y atoms placed at the pentagons of B80 fullerenes showed no clustering effect, and the resulting B80Y12 complex can remarkably bind up to 71 H2 molecules, yielding a gravimetric storage capacity of 6.85 wt%. The interaction between hydrogen molecules and B80Y12 complex is attributed to the Dewar-Kubas mechanism involving the empty \\text{Y}\\text-d orbitals, \\text{H}2\\text-σ orbitals and \\text{H}2\\text-σ* antibonding orbitals. Our work suggests a new route to better hydrogen storage material and advances our fundamental understanding of reversible hydrogen adsorption in nanostructures. 8. 15 K liquid hydrogen thermal Energy Storage Unit for future ESA science missions NASA Astrophysics Data System (ADS) Borges de Sousa, P.; Martins, D.; Tomás, G.; Barreto, J.; Noite, J.; Linder, M.; Fruchart, D.; de Rango, P.; Haettel, R.; Catarino, I.; Bonfait, G. 2015-12-01 A thermal Energy Storage Unit (ESU) using liquid hydrogen has been developed as a solution for absorbing the heat peaks released by the recycling phase of a 300 mK cooler that is a part of the cryogenic chain of one of ESA's new satellites for science missions. This device is capable of storing 400 J of thermal energy between 15 and 16 K by taking advantage of the liquid-to-vapor latent heat of hydrogen in a closed system. This paper describes some results obtained with the development model of the ESU under different configurations and using two types of hydrogen storage: a large expansion volume for ground testing and a much more compact unit, suitable for space applications and that can comply with ESA's mass budget. 9. Boron-double-ring sheet, fullerene, and nanotubes: potential hydrogen storage materials. PubMed Wang, Jing; Zhao, Hui-Yan; Liu, Ying 2014-11-10 Similar to carbon-based graphene, fullerenes and carbon nanotubes, boron atoms can form sheets, fullerenes, and nanotubes. Here we investigate several of these novel boron structures all based on the boron double ring within the framework of density functional theory. The boron sheet is found to be metallic and flat in its ground state. The spherical boron cage containing 180 atoms is also stable and has I symmetry. Stable nanotubes are obtained by rolling up the boron sheet, and all are metallic. The hydrogen storage capacity of boron nanostructures is also explored, and it is found that Li-decorated boron sheets and nanotubes are potential candidates for hydrogen storage. For Li-decorated boron sheets, each Li atom can adsorb a maximum of 4 H2 molecules with g(d) =7.892 wt %. The hydrogen gravimetric density increases to g(d) =12.309 wt % for the Li-decorated (0,6) boron nanotube. 10. Hydrogen storage materials discovery via high throughput ball milling and gas sorption. PubMed Li, Bin; Kaye, Steven S; Riley, Conor; Greenberg, Doron; Galang, Daniel; Bailey, Mark S 2012-06-11 The lack of a high capacity hydrogen storage material is a major barrier to the implementation of the hydrogen economy. To accelerate discovery of such materials, we have developed a high-throughput workflow for screening of hydrogen storage materials in which candidate materials are synthesized and characterized via highly parallel ball mills and volumetric gas sorption instruments, respectively. The workflow was used to identify mixed imides with significantly enhanced absorption rates relative to Li2Mg(NH)2. The most promising material, 2LiNH2:MgH2 + 5 atom % LiBH4 + 0.5 atom % La, exhibits the best balance of absorption rate, capacity, and cycle-life, absorbing >4 wt % H2 in 1 h at 120 °C after 11 absorption-desorption cycles. 11. Ternary Amides Containing Transition Metals for Hydrogen Storage: A Case Study with Alkali Metal Amidozincates. PubMed Cao, Hujun; Richter, Theresia M M; Pistidda, Claudio; Chaudhary, Anna-Lisa; Santoru, Antonio; Gizer, Gökhan; Niewa, Rainer; Chen, Ping; Klassen, Thomas; Dornheim, Martin 2015-11-01 The alkali metal amidozincates Li4 [Zn(NH2)4](NH2)2 and K2[Zn(NH2)4] were, to the best of our knowledge, studied for the first time as hydrogen storage media. Compared with the LiNH2-2 LiH system, both Li4 [Zn(NH2)4](NH2)2-12 LiH and K2[Zn(NH2)4]-8 LiH systems showed improved rehydrogenation performance, especially K2[Zn(NH2)4]-8 LiH, which can be fully hydrogenated within 30 s at approximately 230 °C. The absorption properties are stable upon cycling. This work shows that ternary amides containing transition metals have great potential as hydrogen storage materials. 12. Synthesis, characterization, and modeling of hydrogen storage in carbon aerogels SciTech Connect Pekala, R.W.; Coronado, P.R.; Calef, D.F. 1995-04-01 Carbon aerogels are a special class of open-cell foams with an ultrafine cell/pore size (<50 nm), high surface area (600-800 m{sup 2}/g), and a solid matrix composed of interconnected colloidal-like particles or fibers with characteristic diameters of 10 nm. These materials are usually synthesized from the sol-gel polymerization of resorcinol-formaldehyde or phenolic-furfural, followed by supercritical extraction of the solvent and pyrolysis in an inert atmosphere. The resultant aerogel has a nanocrystalline structure with micropores (<2 nm diameter) located within the solid matrix. Carbon aerogel monoliths can be prepared at densities ranging from 0.05-1.0 g/cm{sup 3}, leading to volumetric surface areas (> 500 m{sup 2}/cm{sup 3}) that are much larger than commercially available materials. This research program is directed at optimization of the aerogel structure for maximum hydrogen adsorption over a wide range of temperatures and pressures. Computer modeling of hydrogen adsorption at carbon surfaces was also examined. 13. Mechanism of activation of TiFe intermetallics for hydrogen storage by severe plastic deformation using high-pressure torsion NASA Astrophysics Data System (ADS) Edalati, Kaveh; Matsuda, Junko; Arita, Makoto; Daio, Takeshi; Akiba, Etsuo; Horita, Zenji 2013-09-01 TiFe, a potential candidate for solid-state hydrogen storage, does not absorb hydrogen without a sophisticated activation process because of severe oxidation. This study shows that nanostructured TiFe becomes active by high-pressure torsion (HPT) and is not deactivated even after storage for several hundred days in the air. Surface segregation and formation of Fe-rich islands and cracks occur after HPT. The Fe-rich islands are suggested to act as catalysts for hydrogen dissociation and cracks and nanograin boundaries act as pathways to transport hydrogen through the oxide layer. Rapid atomic diffusion by HPT is responsible for enhanced surface segregation and hydrogen transportation. 14. Potassium silanide (KSiH3): a reversible hydrogen storage material. PubMed Chotard, Jean-Noël; Tang, Wan Si; Raybaud, Pascal; Janot, Raphaël 2011-10-24 KSi silicide can absorb hydrogen to directly form the ternary KSiH(3) hydride. The full structure of α-KSiD(3), which has been solved by using neutron powder diffraction (NPD), shows an unusually short Si-D lengths of 1.47 Å. Through a combination of density functional theory (DFT) calculations and experimental methods, the thermodynamic and structural properties of the KSi/α-KSiH(3) system are determined. This system is able to store 4.3 wt% of hydrogen reversibly within a good P-T window; a 0.1 MPa hydrogen equilibrium pressure can be obtained at around 414 K. The DFT calculations and the measurements of hydrogen equilibrium pressures at different temperatures give similar values for the dehydrogenation enthalpy (≈23 kJ mol(-1) H(2)) and entropy (≈54 J K(-1) mol(-1) H(2)). Owing to its relatively high hydrogen storage capacity and its good thermodynamic values, this KSi/α-KSiH(3) system is a promising candidate for reversible hydrogen storage. 15. Potassium silanide (KSiH3): a reversible hydrogen storage material. PubMed Chotard, Jean-Noël; Tang, Wan Si; Raybaud, Pascal; Janot, Raphaël 2011-10-24 KSi silicide can absorb hydrogen to directly form the ternary KSiH(3) hydride. The full structure of α-KSiD(3), which has been solved by using neutron powder diffraction (NPD), shows an unusually short Si-D lengths of 1.47 Å. Through a combination of density functional theory (DFT) calculations and experimental methods, the thermodynamic and structural properties of the KSi/α-KSiH(3) system are determined. This system is able to store 4.3 wt% of hydrogen reversibly within a good P-T window; a 0.1 MPa hydrogen equilibrium pressure can be obtained at around 414 K. The DFT calculations and the measurements of hydrogen equilibrium pressures at different temperatures give similar values for the dehydrogenation enthalpy (≈23 kJ mol(-1) H(2)) and entropy (≈54 J K(-1) mol(-1) H(2)). Owing to its relatively high hydrogen storage capacity and its good thermodynamic values, this KSi/α-KSiH(3) system is a promising candidate for reversible hydrogen storage. PMID:21953694 16. Hydrogen storage in Li-doped fullerene-intercalated hexagonal boron nitrogen layers NASA Astrophysics Data System (ADS) Cheng, Yi-Han; Zhang, Chuan-Yu; Ren, Juan; Tong, Kai-Yu 2016-10-01 New materials for hydrogen storage of Li-doped fullerene (C20, C28, C36, C50, C60, C70)-intercalated hexagonal boron nitrogen ( h-BN) frameworks were designed by using density functional theory (DFT) calculations. First-principles molecular dynamics (MD) simulations showed that the structures of the C n -BN ( n = 20, 28, 36, 50, 60, and 70) frameworks were stable at room temperature. The interlayer distance of the h-BN layers was expanded to 9.96-13.59 Å by the intercalated fullerenes. The hydrogen storage capacities of these three-dimensional (3D) frameworks were studied using grand canonical Monte Carlo (GCMC) simulations. The GCMC results revealed that at 77 K and 100 bar (10 MPa), the C50-BN framework exhibited the highest gravimetric hydrogen uptake of 6.86 wt% and volumetric hydrogen uptake of 58.01 g/L. Thus, the hydrogen uptake of the Li-doped C n -intercalated h-BN frameworks was nearly double that of the non-doped framework at room temperature. Furthermore, the isosteric heats of adsorption were in the range of 10-21 kJ/mol, values that are suitable for adsorbing/desorbing the hydrogen molecules at room temperature. At 193 K (-80 °C) and 100 bar for the Li-doped C50-BN framework, the gravimetric and volumetric uptakes of H2 reached 3.72 wt% and 30.08 g/L, respectively. 17. Technical assessment of cryo-compressed hydrogen storage tank systems for automotive applications. SciTech Connect Ahluwalia, R.; Hua, T.; Peng, J.-K.; Lasher, S.; McKenney, K.; Sinha, J.; Gardiner, M.; Nuclear Engineering Division; TIAX LLC; U.S. DOE 2010-05-01 On-board and off-board performance and cost of cryo-compressed hydrogen storage are assessed and compared to the targets for automotive applications. The on-board performance of the system and high-volume manufacturing cost were determined for liquid hydrogen refueling with a single-flow nozzle and a pump that delivers liquid H{sub 2} to the insulated cryogenic tank capable of being pressurized to 272 atm. The off-board performance and cost of delivering liquid hydrogen were determined for two scenarios in which hydrogen is produced by central steam methane reforming (SMR) or by central electrolysis. The main conclusions are that the cryo-compressed storage system has the potential of meeting the ultimate target for system gravimetric capacity, mid-term target for system volumetric capacity, and the target for hydrogen loss during dormancy under certain conditions of minimum daily driving. However, the high-volume manufacturing cost and the fuel cost for the SMR hydrogen production scenario are, respectively, 2-4 and 1.6-2.4 times the current targets, and the well-to-tank efficiency is well short of the 60% target specified for off-board regenerable materials. 18. Stable Ti-based quasicrystal offers prospect for improved hydrogen storage SciTech Connect Stroud, R.M.; Viano, A.M.; Gibbons, P.C.; Kelton, K.F.; Misture, S.T. 1996-11-01 The desorption of hydrogen from a novel material, a Ti{sub 45}Zr{sub 38}Ni{sub 17}-H quasicrystal, was observed using high-temperature powder x-ray diffraction, demonstrating the potential utility of Ti-based quasicrystals in place of crystalline or amorphous hydrides for hydrogen storage applications. The maximum observed change in hydrogen concentration was from 61 at.{percent}, corresponding to a hydrogen-to-metal ratio (H/M) of 1.54, at 91{degree}C to less than 2.5 at.{percent} (H/M=0.025) at 620{degree}C. The onset temperature of desorption is below 350{degree}C. Surface oxidation was found to promote the formation of crystalline hydride phases. Highly oxidized samples transformed to a mixture of the C14 Laves and C15 Laves crystalline hydrides, and the Ti{sub 2}Ni phase. When the oxidation was less severe, a reversible transformation between the quasicrystal and crystalline hydride phases was clearly observed, demonstrating the stability of the Ti{sub 45}Zr{sub 38}Ni{sub 17} quasicrystal at very low hydrogen concentrations, and temperatures as high as 661{degree}C. This is the first evidence for a stable Ti-based quasicrystal and for reversible hydrogen storage in a quasicrystalline phase. {copyright} {ital 1996 American Institute of Physics.} 19. Ti-decorated graphitic-C3N4 monolayer: A promising material for hydrogen storage NASA Astrophysics Data System (ADS) Zhang, Weibin; Zhang, Zhijun; Zhang, Fuchun; Yang, Woochul 2016-11-01 Ti-decorated graphitic carbon nitride (g-C3N4) monolayer as a promising material system for high-capacity hydrogen storage is proposed through density functional theory calculations. The stability and hydrogen adsorption of Ti-decorated g-C3N4 is analyzed by computing the adsorption energy, the charge population, and electronic density of states. The most stable decoration site of Ti atom is the triangular N hole in g-C3N4 with an adsorption energy of -7.58 eV. The large diffusion energy barrier of the adsorbed Ti atom of ∼6.00 eV prohibits the cluster formation of Ti atoms. The electric field induced by electron redistribution of Ti-adsorbed porous g-C3N4 significantly enhanced hydrogen adsorption up to five H2 molecules at each Ti atom with an average adsorption energy of -0.30 eV/H2. The corresponding hydrogen capacity reaches up to 9.70 wt% at 0 K. In addition, the hydrogen capacity is predicted to be 6.30 wt% at 233 K and all adsorbed H2 are released at 393 K according to molecular dynamics simulation. Thus, the Ti-decorated g-C3N4 monolayer is suggested to be a promising material for hydrogen storage suggested by the DOE for commercial applications. 20. Improved Mg-based alloys for hydrogen storage SciTech Connect Sapru, K.; Ming, L.; Stetson, N.T.; Evans, J. 1998-08-01 The overall objective of this on-going work is to develop low temperature alloys capable of reversibly storing at least 3 wt.% hydrogen, allowing greater than for 2 wt.% at the system level which is required by most applications. Surface modification of Mg can be used to improve its H-sorption kinetics. The authors show here that the same Mg-transition metal-based multi-component alloy when prepared by melt-spinning results in a more homogeneous materials with a higher plateau pressure as compared to preparing the material by mechanical grinding. They have also shown that mechanically alloyed Mg{sub 50}Al{sub 45}Zn{sub 5} results in a sample having a higher plateau pressure. 1. Li(12)Si(60)H(60) fullerene composite: a promising hydrogen storage medium. PubMed Lan, Jianhui; Cao, Dapeng; Wang, Wenchuan 2009-10-27 By using the first-principles DFT calculations, we design a novel hydrogen storage material, Li(12)Si(60)H(60) composite, and validate its geometric stability. It is found that the adsorbed Li atoms do not cluster on the Si(60)H(60) fullerene unlike other metals such as Ti, owing to the relatively low Li-Li binding energy and the inhibition of Si-H bonds. Our results show that the Li-doping enhances the hydrogen adsorption ability of Si(60)H(60) significantly, owing to the charge transfer from the doped Li atoms to the host material and the polarization of the adsorbed H(2) molecules. By combining the first-principles calculation and grand canonical Monte Carlo simulation, we further investigate the hydrogen storage capacity of the simulation-synthesized exohedral Li(12)Si(60)H(60) composite at T = 77 K. As the vdW gap (i.e., the separation between the surfaces of two Li(12)Si(60)H(60) fullerenes) is equal to 8.2 A, the total hydrogen uptake of the square-arranged Li(12)Si(60)H(60) array reaches 12.83 wt % at p = 10 MPa, while the excess hydrogen uptake shows a maximum of 7.46 wt % at p = 6 MPa. Impressively, at T = 298 K and p = 10 MPa, the Li(12)Si(60)H(60) array still exhibits a total hydrogen uptake of 3.88 wt % at the vdW gap of 8.2 A. These results clearly indicate that the composite, Li(12)Si(60)H(60) fullerene, is a promising candidate for hydrogen storage. 2. Core--strategy leading to high reversible hydrogen storage capacity for NaBH4. PubMed Christian, Meganne L; Aguey-Zinsou, Kondo-François 2012-09-25 Owing to its high storage capacity (10.8 mass %), sodium borohydride (NaBH(4)) is a promising hydrogen storage material. However, the temperature for hydrogen release is high (>500 °C), and reversibility of the release is unachievable under reasonable conditions. Herein, we demonstrate the potential of a novel strategy leading to high and stable hydrogen absorption/desorption cycling for NaBH(4) under mild pressure conditions (4 MPa). By an antisolvent precipitation method, the size of NaBH(4) particles was restricted to a few nanometers (<30 nm), resulting in a decrease of the melting point and an initial release of hydrogen at 400 °C. Further encapsulation of these nanoparticles upon reaction of nickel chloride at their surface allowed the synthesis of a core--shell nanostructure, NaBH(4)@Ni, and this provided a route for (a) the effective nanoconfinement of the melted NaBH(4) core and its dehydrogenation products, and (b) reversibility and fast kinetics owing to short diffusion lengths, the unstable nature of nickel borohydride, and possible modification of reaction paths. Hence at 350 °C, a reversible and steady hydrogen capacity of 5 mass % was achieved for NaBH(4)@Ni; 80% of the hydrogen could be desorbed or absorbed in less than 60 min, and full capacity was reached within 5 h. To the best of our knowledge, this is the first time that such performances have been achieved with NaBH(4). This demonstrates the potential of the strategy in leading to major advancements in the design of effective hydrogen storage materials from pristine borohydrides. PMID:22873406 3. Core--strategy leading to high reversible hydrogen storage capacity for NaBH4. PubMed Christian, Meganne L; Aguey-Zinsou, Kondo-François 2012-09-25 Owing to its high storage capacity (10.8 mass %), sodium borohydride (NaBH(4)) is a promising hydrogen storage material. However, the temperature for hydrogen release is high (>500 °C), and reversibility of the release is unachievable under reasonable conditions. Herein, we demonstrate the potential of a novel strategy leading to high and stable hydrogen absorption/desorption cycling for NaBH(4) under mild pressure conditions (4 MPa). By an antisolvent precipitation method, the size of NaBH(4) particles was restricted to a few nanometers (<30 nm), resulting in a decrease of the melting point and an initial release of hydrogen at 400 °C. Further encapsulation of these nanoparticles upon reaction of nickel chloride at their surface allowed the synthesis of a core--shell nanostructure, NaBH(4)@Ni, and this provided a route for (a) the effective nanoconfinement of the melted NaBH(4) core and its dehydrogenation products, and (b) reversibility and fast kinetics owing to short diffusion lengths, the unstable nature of nickel borohydride, and possible modification of reaction paths. Hence at 350 °C, a reversible and steady hydrogen capacity of 5 mass % was achieved for NaBH(4)@Ni; 80% of the hydrogen could be desorbed or absorbed in less than 60 min, and full capacity was reached within 5 h. To the best of our knowledge, this is the first time that such performances have been achieved with NaBH(4). This demonstrates the potential of the strategy in leading to major advancements in the design of effective hydrogen storage materials from pristine borohydrides. 4. Technical assessment of cryo-compressed hydrogen storage tank systems for automotive applications. SciTech Connect Ahluwalia, R. K.; Hua, T. Q.; Peng, J.-K.; Lasher, S.; McKenney, K.; Sinha, J.; Nuclear Engineering Division; TIAX LLC 2010-03-03 On-board and off-board performance and cost of cryo-compressed hydrogen storage has been assessed and compared to the DOE 2010, 2015 and ultimate targets for automotive applications. The Gen-3 prototype system of Lawrence Livermore National Laboratory was modeled to project the performance of a scaled-down 5.6-kg usable hydrogen storage system. The on-board performance of the system and high-volume manufacturing cost were determined for liquid hydrogen refueling with a single-flow nozzle and a pump that delivers 1.5 kg/min of liquid H{sub 2} to the insulated cryogenic tank capable of being pressurized to 272 atm (4000 psi). The off-board performance and cost of delivering liquid hydrogen were determined for two scenarios in which hydrogen is produced by central steam methane reforming (SMR) and by central electrolysis using electricity from renewable sources. The main conclusions from the assessment are that the cryo-compressed storage system has the potential of meeting the ultimate target for system gravimetric capacity and the 2015 target for system volumetric capacity (see Table I). The system compares favorably with targets for durability and operability although additional work is needed to understand failure modes for combined pressure and temperature cycling. The system may meet the targets for hydrogen loss during dormancy under certain conditions of minimum daily driving. The high-volume manufacturing cost is projected to be 2-4 times the current 2010 target of4/kWh. For the reference conditions considered most applicable, the fuel cost for the SMR hydrogen production and liquid H{sub 2} delivery scenario is 60%-140% higher than the current target of $2-$3/gge while the well-to-tank efficiency is well short of the 60% target specified for off-board regenerable materials.

5. Hydrogen storage for vehicular applications: Technology status and key development areas

SciTech Connect

Robinson, S.L.; Handrock, J.L.

1994-04-01

The state-of-the-art of hydrogen storage technology is reviewed, including gaseous, liquid, hydride, surface adsorbed media, glass microsphere, chemical reaction, and liquid chemical technologies. The review of each technology includes a discussion of advantages, disadvantages, likelihood of success, and key research and development activities. A preferred technological path for the development of effective near-term hydrogen storage includes both cur-rent DOT qualified and advanced compressed storage for down-sized highly efficient but moderate range vehicles, and liquid storage for fleet vehicle applications. Adsorbate media are also suitable for fleet applications but not for intermittent uses. Volume-optimized transition metal hydride beds are also viable for short range applications. Long-term development of coated nanoparticulate or metal matrix high conductivity magnesium alloy, is recommended. In addition, a room temperature adsorbate medium should be developed to avoid cryogenic storage requirements. Chemical storage and oxidative schemes present serious obstacles which must be addressed for these technologies to have a future role.

6. Low-hydrogen specs challenge large-part fabricator

SciTech Connect

1995-06-01

Recently, Mark Steel Corp. of Salt Lake City completed a contract to build nine large driver tubes as part of a blast thermal simulator for the US Army. The finished device will be used to test the hardenability of various defense products under simulated nuclear blast forces. To create the shock wave component of the blast, the tubes will be charged with compressed nitrogen, which will be released to create an explosive force eight times that of hurricane Andrew, or equivalent to a 35-megaton bomb. To hold critical low-hydrogen specs while welding the large, complex parts, Mark Steel needed a combination of tight temperature control throughout the process, stringent test procedures, two versions of a new ultralow-hydrogen electrode, and a new ultralow-hydrogen submerged arc flux developed for the job by the Lincoln Electric Co. These specs are discussed here.

7. Pillared Graphene: A New 3-D Innovative Network Nanostructure Augments Hydrogen Storage

Georgios, Dimitrakakis K.; Emmanuel, Tylianakis; George, Froudakis E.

2009-08-01

Nowadays, people have turned into finding an alternative power source for everyday applications. One of the most promising energy fuels is hydrogen. It can be used as an energy carrier at small portable devices (e.g. laptops and/or cell phones) up to larger, like cars. Hydrogen is considered as the perfect fuel. It can be burnt in combustion engines and the only by-product is water. For hydrogen-powered vehicles a big liming factor is the gas tank and is the reason for not using widely hydrogen in automobile applications. According to United States' Department of Energy (D.O.E.) the target for reversible hydrogen storage in mobile applications is 6% wt. and 45 gr. H2/L and these should be met by 2010. After their synthesis Carbon Nanotubes (CNTs) were considered as ideal candidates for hydrogen storage especially after some initially incorrect but invitingly results. As it was proven later, pristine carbon nanotubes cannot achieve D.O.E.'s targets in ambient conditions of pressure and temperature. Therefore, a way to increase their hydrogen storage capacity should be found. An attempt was done by doping CNTs with alkali metal atoms. Although the results were promising, even that increment was not enough. Consequently, new architectures were suggested as materials that could potentially enhance hydrogen storage. In this work a novel three dimensional (3-D) nanoporous carbon structure called Pillared Graphene (Figure 1) is proposed for augmented hydrogen storage in ambient conditions. Pillared Graphene consists of parallel graphene sheets and CNTs that act like pillars and support the graphene sheets. The entire structure (Figure 1) can be resembled like a building in its early stages of construction, where the floors are represented by graphene sheets and the pillars are the CNTs. As shown in Figure 1, CNTs do not penetrate the structure from top to bottom. Instead, they alternately go up and down, so that on the same plane do not exist two neighboring CNTs with the

8. Hydrogen underground storage in siliciclastic reservoirs - intention and topics of the H2STORE project

Pudlo, Dieter; Ganzer, Leonhard; Henkel, Steven; Liebscher, Axel; Kühn, Michael; De Lucia, Marco; Panfilov, Michel; Pilz, Peter; Reitenbach, Viktor; Albrecht, Daniel; Würdemann, Hilke; Gaupp, Reinhard

2013-04-01

The transfer of energy supply from nuclear and CO2-emitting power generation to renewable energy production sources is strongly reliant to the potential of storing high capacities of energy in a safe and reliable way in time spans of several months. One conceivable option can be the storage of hydrogen and (related) synthetic natural gas (SNG) production in appropriate underground structures, like salt caverns and pore space reservoirs. Successful storage of hydrogen in the form of town gas in salt caverns has been proven in several demonstration projects and can be considered as state of the art technology. However, salt structures have only limited importance for hydrogen storage due to only small cavern volumes and the limited occurrence of salt deposits suitable for flushing of cavern constructions. Thus, regarding potential high-volume storage sites, siliciclastic deposits like saline aquifers and depleted gas reservoirs are of increasing interest. Motivated by a project call and sponsored by the German government the H2STORE ("Hydrogen to Store") collaborative project will investigate the feasibility and the requirements for pore space storage of hydrogen. Thereby depleted gas reservoirs are a major concern of this study. This type of geological structure is chosen because of their well investigated geological settings and proved sealing capacities, which already enable a present (and future) use as natural (and synthetic) reservoir gas storages. Nonetheless hydrogen and hydrocarbon in porous media exhibit major differences in physico-chemical behaviour, essentially due to the high diffusivity and reactivity of hydrogen. The biotic and abiotic reactions of hydrogen with rocks and fluids will be necessary observed in siliciclastic sediments which consist of numerous inorganic and organic compounds and comprise original formation fluids. These features strongly control petrophysical behaviour (e.g. porosity, permeability) and therefore fluid (hydrogen

9. Thermal and hydraulic effects in the subsurface related to large scale hydrogen storage operations

Pfeiffer, W. T.; Li, D.; Dethlefsen, F.; Bauer, S.

2014-12-01

Energy production from renewable sources such as wind or solar power is subject to natural temporal fluctuations. Therefore, energy storage will become indispensable when renewable sources represent a substantial share in the total energy production. Subsurface storage of synthetically produced hydrogen in porous sandstone formations is particularly suited for large amounts of energy and relatively long production cycles. The increasing use of the subsurface, however, demands for an a priori analysis of possible effects of a storage operation in order to minimize environmental risks and interference with other usages, such as geothermal energy storage or groundwater abstraction. In this context, this work aims at an assessment of thermal and hydraulic impacts of a hypothetical hydrogen storage scenario in an anticlinal structure in northern Germany using numerical process simulations. The storage structure consists of partially eroded Rhaetian sandstones acting as the storage formation with the upper barrier formations being mud- and chalkstones of the Lower Jurassic and Lower Cretaceous. The storage operation was modeled over a period of one year using three wells located on the flank of the structure near its top. Each production cycle was set to a duration of seven days in which an equivalent of around 280000 GJ were extracted. The numerical simulations were carried out using the Eclipse E300 simulator (Schlumberger) in conjunction with the open source THMC-simulator OpenGeoSys, where the hydraulic- and mass transport processes are solved by Eclipse and the heat transport processes by OpenGeoSys. The simulation results show that the thermal effects due to the storage operation are mainly limited to the immediate vicinity of the storage wells, thus their reach is on the decimeter to meter scale. Since heat transport is dominated by thermal conduction this also includes the sealing formations above and below the storage formation. Moreover, the propagation of

10. Simple and Efficient System for Combined Solar Energy Harvesting and Reversible Hydrogen Storage.

PubMed

Li, Lu; Mu, Xiaoyue; Liu, Wenbo; Mi, Zetian; Li, Chao-Jun

2015-06-24

Solar energy harvesting and hydrogen economy are the two most important green energy endeavors for the future. However, a critical hurdle to the latter is how to safely and densely store and transfer hydrogen. Herein, we developed a reversible hydrogen storage system based on low-cost liquid organic cyclic hydrocarbons at room temperature and atmospheric pressure. A facile switch of hydrogen addition (>97% conversion) and release (>99% conversion) with superior capacity of 7.1 H2 wt % can be quickly achieved over a rationally optimized platinum catalyst with high electron density, simply regulated by dark/light conditions. Furthermore, the photodriven dehydrogenation of cyclic alkanes gave an excellent apparent quantum efficiency of 6.0% under visible light illumination (420-600 nm) without any other energy input, which provides an alternative route to artificial photosynthesis for directly harvesting and storing solar energy in the form of chemical fuel. PMID:26059734

11. Amorphous magnesium-nickel hydrogen-storage alloys synthesized by sputtering

SciTech Connect

Holtz, R.L.; Imam, M.A.; Meyn, D.A.

1995-12-31

Magnesium-based alloys are potentially important hydrogen-storage materials because of their light weight and high specific hydrogen capacities. In thin film form, it should be possible to engineer the hydride reaction kinetics and protect the materials from oxidation by applying passivation or catalytic layers. In the present work, thin films of Mg-Ni alloys were deposited by cosputtering onto a liquid nitrogen cooled substrate. The films were amorphous as deposited. Upon hydriding at 354 C in 2.1 MPa of hydrogen, the films crystallize and fragment into fine powders. Hydrogen uptakes very close to the theoretical maximum are obtained for Mg-Ni alloys with 15, 33, and 60 atomic percent nickel.

12. Hydrogen Station Compression, Storage, and Dispensing Technical Status and Costs: Systems Integration

SciTech Connect

Parks, G.; Boyd, R.; Cornish, J.; Remick, R.

2014-05-01

At the request of the U.S. Department of Energy Fuel Cell Technologies Office (FCTO), the National Renewable Energy Laboratory commissioned an independent review of hydrogen compression, storage, and dispensing (CSD) for pipeline delivery of hydrogen and forecourt hydrogen production. The panel was asked to address the (1) cost calculation methodology, (2) current cost/technical status, (3) feasibility of achieving the FCTO's 2020 CSD levelized cost targets, and to (4) suggest research areas that will help the FCTO reach its targets. As the panel neared the completion of these tasks, it was also asked to evaluate CSD costs for the delivery of hydrogen by high-pressure tube trailer. This report details these findings.

13. Hydrogen storage in microporous metal-organic frameworks with exposed metal sites.

PubMed

Dincă, Mircea; Long, Jeffrey R

2008-01-01

Owing to their high uptake capacity at low temperature and excellent reversibility kinetics, metal-organic frameworks have attracted considerable attention as potential solid-state hydrogen storage materials. In the last few years, researchers have also identified several strategies for increasing the affinity of these materials towards hydrogen, among which the binding of H(2) to unsaturated metal centers is one of the most promising. Herein, we review the synthetic approaches employed thus far for producing frameworks with exposed metal sites, and summarize the hydrogen uptake capacities and binding energies in these materials. In addition, results from experiments that were used to probe independently the metal-hydrogen interaction in selected materials will be discussed.

14. Simple and Efficient System for Combined Solar Energy Harvesting and Reversible Hydrogen Storage.

PubMed

Li, Lu; Mu, Xiaoyue; Liu, Wenbo; Mi, Zetian; Li, Chao-Jun

2015-06-24

Solar energy harvesting and hydrogen economy are the two most important green energy endeavors for the future. However, a critical hurdle to the latter is how to safely and densely store and transfer hydrogen. Herein, we developed a reversible hydrogen storage system based on low-cost liquid organic cyclic hydrocarbons at room temperature and atmospheric pressure. A facile switch of hydrogen addition (>97% conversion) and release (>99% conversion) with superior capacity of 7.1 H2 wt % can be quickly achieved over a rationally optimized platinum catalyst with high electron density, simply regulated by dark/light conditions. Furthermore, the photodriven dehydrogenation of cyclic alkanes gave an excellent apparent quantum efficiency of 6.0% under visible light illumination (420-600 nm) without any other energy input, which provides an alternative route to artificial photosynthesis for directly harvesting and storing solar energy in the form of chemical fuel.

15. Yttrium-dispersed C{sub 60} fullerenes as high-capacity hydrogen storage medium

SciTech Connect

Tian, Zi-Ya; Dong, Shun-Le

2014-02-28

Interaction between hydrogen molecules and functionalized C{sub 60} is investigated using density functional theory method. Unlike transition metal atoms that tend to cluster on the surface, C{sub 60} decorated with 12 Yttrium atoms on each of its 12 pentagons is extremely stable and remarkably enhances the hydrogen adsorption capacity. Four H{sub 2} molecules can be chemisorbed on a single Y atom through well-known Dewar-Chatt-Duncanson interaction. The nature of bonding is a weak physisorption for the fifth adsorbed H{sub 2} molecule. Consequently, the C{sub 60}Y{sub 12} complex with 60 hydrogen molecules has been demonstrated to lead to a hydrogen storage capacity of ∼6.30 wt. %.

16. Thermal Performance Comparison of Glass Microsphere and Perlite Insulation Systems for Liquid Hydrogen Storage Tanks

Sass, J. P.; Fesmire, J. E.; Nagy, Z. F.; Sojourner, S. J.; Morris, D. L.; Augustynowicz, S. D.

2008-03-01

A technology demonstration test project was conducted by the Cryogenics Test Laboratory at the Kennedy Space Center (KSC) to provide comparative thermal performance data for glass microspheres, referred to as bubbles, and perlite insulation for liquid hydrogen tank applications. Two identical 1/15th scale versions of the 3,200,000 liter spherical liquid hydrogen tanks at Launch Complex 39 at KSC were custom designed and built to serve as test articles for this test project. Evaporative (boil-off) calorimeter test protocols, including liquid nitrogen and liquid hydrogen, were established to provide tank test conditions characteristic of the large storage tanks that support the Space Shuttle launch operations. This paper provides comparative thermal performance test results for bubbles and perlite for a wide range of conditions. Thermal performance as a function of cryogenic commodity (nitrogen and hydrogen), vacuum pressure, insulation fill level, tank liquid level, and thermal cycles will be presented.

17. Energy Dense, Lighweight, Durable, Systems for Storage and Delivery of Hydrogen

SciTech Connect

Jacky Pruez; Samir Shoukry; Gergis William; Thomas Evans; Hermann Alcazar

2008-12-31

The work presented in this report summarizes the current state-of-the-art in on-board storage on compressed gaseous hydrogen as well as the development of analysis tools, methods, and theoretical data for devising high performance design configurations for hydrogen storage. The state-of-the-art in the area of compressed hydrogen storage reveals that the current configuration of the hydrogen storage tank is a seamless cylindrical part with two end domes. The tank is composed of an aluminum liner overwrapped with carbon fibers. Such a configuration was proved to sustain internal pressures up to 350 bars (5,000 psi). Finite-element stress analyses were performed on filament-wound hydrogen storage cylindrical tanks under the effect of internal pressure of 700 bars (10,000 psi). Tank deformations, stress fields, and intensities induced at the tank wall were examined. The results indicated that the aluminum liner can not sustain such a high pressure and initiate the tank failure. Thus, hydrogen tanks ought to be built entirely out of composite materials based on carbon fibers or other innovative composite materials. A spherical hydrogen storage tank was suggested within the scope of this project. A stress reduction was achieved by this change of the tank geometry, which allows for increasing the amount of the stored hydrogen and storage energy density. The finite element modeling of both cylindrical and spherical tank design configurations indicate that the formation of stress concentration zones in the vicinity of the valve inlet as well as the presence of high shear stresses in this area. Therefore, it is highly recommended to tailor the tank wall design to be thicker in this region and tapered to the required thickness in the rest of the tank shell. Innovative layout configurations of multiple tanks for enhanced conformability in limited space have been proposed and theoretically modeled using 3D finite element analysis. Optimum tailoring of fiber orientations and lay

18. Phase, microstructure and hydrogen storage properties of Mg-Ni materials synthesized from metal nanoparticles

Shao, Huaiyu; Chen, Chunguang; Liu, Tong; Li, Xingguo

2014-04-01

After Mg and Ni nanoparticles were fabricated by hydrogen plasma metal reaction, Mg-rich MgxNi100-x(75 < x < 90) materials were synthesized from these metal nanoparticles to study the synergistic effects for hydrogen storage in these samples to show both good kinetics and high capacity. These MgxNi100-x materials may absorb hydrogen with a capacity of around 3.3-5.1 wt% in 1 min at 573 K. The Mg90Ni10 sample shows a hydrogen capacity of 6.1 wt%. The significant kinetic enhancement is thought to be due to the unique nanostructure from the special synthesis route, the catalytic effect of the Mg2Ni nano phase, and the synergistic effects between the Mg2Ni and Mg phases in the materials. An interesting phenomenon which has never been reported before was observed during pressure composition isotherm (PCT) measurements. One steep step in the absorption process and two obviously separated steps in the desorption process during PCT measurements of Mg80Ni20 and Mg90Ni10 samples were observed and a possible reason from the kinetic performance of the Mg2Ni and Mg phases in absorption and desorption processes was explained. These MgxNi100-x materials synthesized from Mg and Ni nanoparticles show high capacity and good kinetics, which makes these materials very promising candidates for thermal storage or energy storage and utilization for renewable power.

19. Phase, microstructure and hydrogen storage properties of Mg-Ni materials synthesized from metal nanoparticles.

PubMed

Shao, Huaiyu; Chen, Chunguang; Liu, Tong; Li, Xingguo

2014-04-01

After Mg and Ni nanoparticles were fabricated by hydrogen plasma metal reaction, Mg-rich MgxNi₁₀₀₋x(75 < x < 90) materials were synthesized from these metal nanoparticles to study the synergistic effects for hydrogen storage in these samples to show both good kinetics and high capacity. These MgxNi₁₀₀₋x materials may absorb hydrogen with a capacity of around 3.3-5.1 wt% in 1 min at 573 K. The Mg₉₀Ni₁₀ sample shows a hydrogen capacity of 6.1 wt%. The significant kinetic enhancement is thought to be due to the unique nanostructure from the special synthesis route, the catalytic effect of the Mg₂Ni nano phase, and the synergistic effects between the Mg₂Ni and Mg phases in the materials. An interesting phenomenon which has never been reported before was observed during pressure composition isotherm (PCT) measurements. One steep step in the absorption process and two obviously separated steps in the desorption process during PCT measurements of Mg₈₀Ni₂₀ and Mg₉₀Ni₁₀ samples were observed and a possible reason from the kinetic performance of the Mg₂Ni and Mg phases in absorption and desorption processes was explained. These MgxNi₁₀₀₋x materials synthesized from Mg and Ni nanoparticles show high capacity and good kinetics, which makes these materials very promising candidates for thermal storage or energy storage and utilization for renewable power.

20. Size-dependent mechanical properties of Mg nanoparticles used for hydrogen storage

SciTech Connect

Yu, Qian; Qi, Liang; Mishra, Raja K.; Zeng, Xiaoqin; Minor, Andrew M.

2015-06-29

Magnesium (Mg) hydride is a promising hydrogen storage material, yet its application has been limited by the slow hydrogen sorption kinetics. Recently, Mg nanoparticles have shown significant improvement of hydrogen storage properties in terms of dimensional stability upon cycling with the trend that the smaller the particle, the better the sorption kinetics. Since the volume change during sorption generates stress, leading to plastic deformation, the fundamentals of the mechanical deformation of the Mg particles are a significant issue. By using in situ transmission electron microscope compression tests and atomistic simulations on Mg nanoparticles, it was observed that deformation in the larger particles was dominated by the nucleation of 〈a〉-type dislocations from stress concentrations at the contact surface, while the smaller particles deformed more homogeneously with greater distribution of multiple types of dislocation sources. Importantly, this improvement of plastic deformation with decrease in size is orientation-independent. First-principles calculations suggest that this improved plasticity can be explained by the nearly-isotropic ideal shear strength for Mg, which becomes more important in smaller nanoparticles. As a result, the smaller Mg nanoparticles demonstrated better plastic stability to accommodate volume change upon hydrogen storage cycling.

1. Model for energy conversion in renewable energy system with hydrogen storage

Kélouwani, S.; Agbossou, K.; Chahine, R.

A dynamic model for a stand-alone renewable energy system with hydrogen storage (RESHS) is developed. In this system, surplus energy available from a photovoltaic array and a wind turbine generator is stored in the form of hydrogen, produced via an electrolyzer. When the energy production from the wind turbine and the photovoltaic array is not enough to meet the load demand, the stored hydrogen can then be converted by a fuel cell to produce electricity. In this system, batteries are used as energy buffers or for short time storage. To study the behavior of such a system, a complete model is developed by integrating individual sub-models of the fuel cell, the electrolyzer, the power conditioning units, the hydrogen storage system, and the batteries (used as an energy buffer). The sub-models are valid for transient and steady state analysis as a function of voltage, current, and temperature. A comparison between experimental measurements and simulation results is given. The model is useful for building effective algorithms for the management, control and optimization of stand-alone RESHSs.

2. "Job-Sharing" Storage of Hydrogen in Ru/Li₂O Nanocomposites.

PubMed

Fu, Lijun; Tang, Kun; Oh, Hyunchul; Manickam, Kandavel; Bräuniger, Thomas; Chandran, C Vinod; Menzel, Alexander; Hirscher, Michael; Samuelis, Dominik; Maier, Joachim

2015-06-10

A "job-sharing" hydrogen storage mechanism is proposed and experimentally investigated in Ru/Li2O nanocomposites in which H(+) is accommodated on the Li2O side, while H(-) or e(-) is stored on the side of Ru. Thermal desorption-mass spectroscopy results show that after loading with D2, Ru/Li2O exhibits an extra desorption peak, which is in contrast to Ru nanoparticles or ball-milled Li2O alone, indicating a synergistic hydrogen storage effect due to the presence of both phases. By varying the ratio of the two phases, it is shown that the effect increases monotonically with the area of the heterojunctions, indicating interface related hydrogen storage. X-ray diffraction, Fourier transform infrared spectroscopy, and nuclear magnetic resonance results show that a weak LiO···D bond is formed after loading in Ru/Li2O nanocomposites with D2. The storage-pressure curve seems to favor H(+)/H(-) over H(+)/e(-) mechanism. PMID:25915434

3. USING POLYMERIC HYDROGEN GETTERS TO PREVENT COMBUSTIBLE ATMOSPHERES DURING INTERIM SAFE STORAGE OF PLUTONIUM OXIDE

SciTech Connect

Woodsmall, T

2007-05-24

Nuclear Materials Management (NMM) of WSRC has recently installed the capability to perform both non-destructive and destructive examination of 3013 containers of Pu oxide in accordance with DOE-STD-3013. The containers will be opened and the oxide will be sampled for analysis. The remaining bulk oxide must then be safely stored in a non-3013-compliant configuration. Available processing equipment and controls cannot prevent the oxide from adsorbing moisture during this process. Subsequent radiolysis of moisture during storage may generate combustible quantities of gases while waiting final processing, and satisfying DOE Interim Safe Storage Criteria (ISSC) would require that storage containers be vented at impractical frequencies. With support from an independent National Laboratory, WSRC/NMM has demonstrated that a commercial hydrogen getter material will effectively prevent the accumulation of combustible gas concentrations. A project overview, including storage requirements and strategies, as well as getter technology, current test results, and anticipated future developments will be addressed.

4. Capacity loss on storage and possible capacity recovery for HST nickel-hydrogen cells

NASA Technical Reports Server (NTRS)

Lowery, John E.

1992-01-01

Negatively precharged nickel hydrogen cells will experience a useable capacity loss during extended open circuit storage periods. Some of the lost capacity can be recovered through cycling. Capacity recovery through cycling can be enhanced by cycling at high depths of discharge (DOD). The most timely procedure for recovering the faded capacity is to charge the cell fully and allow the cell to sit open-circuit at room temperature. This procedure seems to be effective in part because of the enlarged structure of the active materials. The compounds that formed during storage at the low electrode potentials can more easily dissolve and redistribute. All of the original capacity cannot be recovered because the lattice structure of the active material is irreversibly altered during storage. The recommendation is to use positively precharged cells activated with 26 percent KOH if possible. In aerospace applications, the benefits of negative precharge are offset by the possibility of delays and storage periods.

5. Design and synthesis of vanadium hydrazide gels for Kubas-type hydrogen adsorption: a new class of hydrogen storage materials.

PubMed

Hoang, Tuan K A; Webb, Michael I; Mai, Hung V; Hamaed, Ahmad; Walsby, Charles J; Trudeau, Michel; Antonelli, David M

2010-08-25

In this paper we demonstrate that the Kubas interaction, a nondissociative form of weak hydrogen chemisorption with binding enthalpies in the ideal 20-30 kJ/mol range for room-temperature hydrogen storage, can be exploited in the design of a new class of hydrogen storage materials which avoid the shortcomings of hydrides and physisorpion materials. This was accomplished through the synthesis of novel vanadium hydrazide gels that use low-coordinate V centers as the principal Kubas H(2) binding sites with only a negligible contribution from physisorption. Materials were synthesized at vanadium-to-hydrazine ratios of 4:3, 1:1, 1:1.5, and 1:2 and characterized by X-ray powder diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption, elemental analysis, infrared spectroscopy, and electron paramagnetic resonance spectroscopy. The material with the highest capacity possesses an excess reversible storage of 4.04 wt % at 77 K and 85 bar, corresponding to a true volumetric adsorption of 80 kg H(2)/m(3) and an excess volumetric adsorption of 60.01 kg/m(3). These values are in the range of the ultimate U.S. Department of Energy goal for volumetric density (70 kg/m(3)) as well as the best physisorption material studied to date (49 kg H(2)/m(3) for MOF-177). This material also displays a surprisingly high volumetric density of 23.2 kg H(2)/m(3) at room temperature and 85 bar--roughly 3 times higher than that of compressed gas and approaching the DOE 2010 goal of 28 kg H(2)/m(3). These materials possess linear isotherms and enthalpies that rise on coverage and have little or no kinetic barrier to adsorption or desorption. In a practical system these materials would use pressure instead of temperature as a toggle and can thus be used in compressed gas tanks, currently employed in many hydrogen test vehicles, to dramatically increase the amount of hydrogen stored and therefore the range of any vehicle.

6. Chemical Hydrogen Storage Using Polyhedral Borane Anions and Aluminum-Ammonia-Borane Complexes

SciTech Connect

Hawthorne, M. Frederick; Jalisatgi, Satish S.; Safronov, Alexander V.; Lee, Han Beak; Wu, Jianguo

2010-10-01

Phase 1. Hydrolysis of borohydride compounds offer the potential for significant hydrogen storage capacity, but most work to date has focused on one particular anion, BH4-, which requires high pH for stability. Other borohydride compounds, in particular polyhedral borane anions offer comparable hydrogen storage capacity without requiring high pH media and their long term thermal and hydrolytic stability coupled with non-toxic nature make them a very attractive alternative to NaBH4. The University of Missouri project provided the overall program focal point for the investigation of catalytic hydrolysis of polyhedral borane anions for hydrogen release. Due to their inherent stability, a transition metal catalyst was necessary for the hydrolysis of polyhedral borane anions. Transition metal ions such as cobalt, nickel, palladium and rhodium were investigated for their catalytic activity in the hydrolysis of nido-KB11H14, closo-K2B10H10, and closo-K2B12H12. The rate of hydrolysis follows first-order kinetics with respect to the concentration of the polyhedral borane anion and surface area of the rhodium catalyst. The rate of hydrolysis depends upon a) choice of polyhedral borane anion, c) concentration of polyhedral borane anion, d) surface area of the rhodium catalyst and e) temperature of the reaction. In all cases the yield of hydrogen was 100% which corresponds to ~7 wt% of hydrogen (based on material wt%). Phase 2. The phase 2 of program at the University of Missouri was focused upon developing aluminum ammonia-boranes (Al-AB) as chemical hydrogen storage materials, specifically their synthesis and studies of their dehydrogenation. The ammonia borane molecule (AB) is a demonstrated source of chemically stored hydrogen (19.6 wt%) which meets DOE performance parameters except for its regeneration from spent AB and elemental hydrogen. The presence of an aluminum center bonded to multiple AB residues might combine the efficiency of AB dehydrogenation with an aluminum

7. Graphene-based materials: fabrication, characterization and application for the decontamination of wastewater and wastegas and hydrogen storage/generation.

PubMed

Wang, Hou; Yuan, Xingzhong; Wu, Yan; Huang, Huajun; Peng, Xin; Zeng, Guangming; Zhong, Hua; Liang, Jie; Ren, Miaomiao

2013-07-01

Graphene, as an ideal two-dimensional material and single-atom layer of graphite, has attracted exploding interests in multidisciplinary research because of its unique structure and exceptional physicochemical properties. Especially, graphene-based materials offer a wide range of potentialities for environmental remediation and energy applications. This review shows an extensive overview of the main principles and the recent synthetic technologies about designing and fabricating various innovative graphene-based materials. Furthermore, an extensive list of graphene-based sorbents and catalysts from vast literature has been compiled. The adsorptive and catalytic properties of graphene-based materials for the removal of various pollutants and hydrogen storage/production as available in the literature are presented. Tremendous adsorption capacity, excellent catalytic performance and abundant availability are the significant factors making these materials suitable alternatives for environmental pollutant control and energy-related system, especially in terms of the removal of pollutants in water, gas cleanup and purification, and hydrogen generation and storage. Meanwhile, a brief discussion is also included on the influence of graphene materials on the environment, and its toxicological effects. Lastly, some unsolved subjects together with major challenges in this germinating area of research are highlighted and discussed. Conclusively, the expanding of graphene-based materials in the field of adsorption and catalysis science represents a viable and powerful tool, resulting in the superior improvement of environmental pollution control and energy development.

8. Reversible phase modulation and hydrogen storage in multivalent VO2 epitaxial thin films

Yoon, Hyojin; Choi, Minseok; Lim, Tae-Won; Kwon, Hyunah; Ihm, Kyuwook; Kim, Jong Kyu; Choi, Si-Young; Son, Junwoo

2016-10-01

Hydrogen, the smallest and the lightest atomic element, is reversibly incorporated into interstitial sites in vanadium dioxide (VO2), a correlated oxide with a 3d1 electronic configuration, and induces electronic phase modulation. It is widely reported that low hydrogen concentrations stabilize the metallic phase, but the understanding of hydrogen in the high doping regime is limited. Here, we demonstrate that as many as two hydrogen atoms can be incorporated into each VO2 unit cell, and that hydrogen is reversibly absorbed into, and released from, VO2 without destroying its lattice framework. This hydrogenation process allows us to elucidate electronic phase modulation of vanadium oxyhydride, demonstrating two-step insulator (VO2)-metal (HxVO2)-insulator (HVO2) phase modulation during inter-integer d-band filling. Our finding suggests the possibility of reversible and dynamic control of topotactic phase modulation in VO2 and opens up the potential application in proton-based Mottronics and novel hydrogen storage.

9. Storage of molecular hydrogen in B-N cage: energetics and thermal stability.

PubMed

Sun, Qiang; Wang, Qian; Jena, Puru

2005-07-01

Using first principles theory based on density functional formulation we have studied the energetics and thermal stability of storing hydrogen in B-N-based nanostructures. We show that hydrogen molecule enters through the hexagonal face of the B36N36 cage and prefers to remain inside the cage in molecular form. The energy barriers for the hydrogen molecule to enter into or escape from the cage are respectively 1.406 eV and 1.516 eV. As the concentration of hydrogen inside the cage increases, the cage expands and the bond length of the hydrogen molecule contracts, resulting in significant energy cost. At zero temperature, up to 18 hydrogen molecules can be stored inside a B36N36 cage corresponding to a gravimetric density of 4 wt %. However, molecular dynamics simulation by using Nose algorithm at room temperature (T = 300 K) indicates that high weight percentage hydrogen storage cannot be achieved in B-N cage structures and thus these materials may not be good for practical applications.

10. Reversible phase modulation and hydrogen storage in multivalent VO2 epitaxial thin films.

PubMed

Yoon, Hyojin; Choi, Minseok; Lim, Tae-Won; Kwon, Hyunah; Ihm, Kyuwook; Kim, Jong Kyu; Choi, Si-Young; Son, Junwoo

2016-10-01

Hydrogen, the smallest and the lightest atomic element, is reversibly incorporated into interstitial sites in vanadium dioxide (VO2), a correlated oxide with a 3d(1) electronic configuration, and induces electronic phase modulation. It is widely reported that low hydrogen concentrations stabilize the metallic phase, but the understanding of hydrogen in the high doping regime is limited. Here, we demonstrate that as many as two hydrogen atoms can be incorporated into each VO2 unit cell, and that hydrogen is reversibly absorbed into, and released from, VO2 without destroying its lattice framework. This hydrogenation process allows us to elucidate electronic phase modulation of vanadium oxyhydride, demonstrating two-step insulator (VO2)-metal (HxVO2)-insulator (HVO2) phase modulation during inter-integer d-band filling. Our finding suggests the possibility of reversible and dynamic control of topotactic phase modulation in VO2 and opens up the potential application in proton-based Mottronics and novel hydrogen storage.

11. Advanced chemical hydride-based hydrogen generation/storage system for fuel cell vehicles

SciTech Connect

Breault, R.W.; Rolfe, J.

1998-08-01

Because of the inherent advantages of high efficiency, environmental acceptability, and high modularity, fuel cells are potentially attractive power supplies. Worldwide concerns over clean environments have revitalized research efforts on developing fuel cell vehicles (FCV). As a result of intensive research efforts, most of the subsystem technology for FCVs are currently well established. These include: high power density PEM fuel cells, control systems, thermal management technology, and secondary power sources for hybrid operation. For mobile applications, however, supply of hydrogen or fuel for fuel cell operation poses a significant logistic problem. To supply high purity hydrogen for FCV operation, Thermo Powers Advanced Technology Group is developing an advanced hydrogen storage technology. In this approach, a metal hydride/organic slurry is used as the hydrogen carrier and storage media. At the point of use, high purity hydrogen will be produced by reacting the metal hydride/organic slurry with water. In addition, Thermo Power has conceived the paths for recovery and regeneration of the spent hydride (practically metal hydroxide). The fluid-like nature of the spent hydride/organic slurry will provide a unique opportunity for pumping, transporting, and storing these materials. The final product of the program will be a user-friendly and relatively high energy storage density hydrogen supply system for fuel cell operation. In addition, the spent hydride can relatively easily be collected at the pumping station and regenerated utilizing renewable sources, such as biomass, natural, or coal, at the central processing plants. Therefore, the entire process will be economically favorable and environmentally friendly.

12. Robustness and Thermophysical Properties of MOF-5: A Prototypical Hydrogen Storage Material

Ming, Yang

Metal-organic frameworks (MOFs) are an emerging class of microporous, crystalline materials with potential applications in the capture, storage, and separation of gasses. Of the many known MOFs, the compound known as MOF-5 has attracted considerable attention due to its ability to store gaseous fuels at low pressure with high densities. However, low thermal conductivity and limited robustness upon exposure to water and other reactive species are two challenges which limit the application of MOF-5; similar issues plague several other MOFs. The focus of this dissertation is to understand and overcome these shortcomings through detailed experimental and computational characterization of the prototype compound, MOF-5. The insight provided by this study regarding the properties of MOFs will aid in the transition of these materials from lab bench to applications. Improvements to the thermal conductivity of MOF-5 are demonstrated using densified pellets consisting of a physical mixture of MOF-5 and expanded natural graphite (ENG). The high-aspect ratio of ENG particles, combined with uni-axial compression, results in anisotropic microstructural and thermal transport properties in the pellets. Perpendicular to the pressing direction the thermal conductivity was observed to be two to four times higher than in the orthogonal direction. We further demonstrate that this anisotropy can be exploited to enhance conductivity along a preferred direction in the pellets by altering the pellet processing conditions. We conclude that the low thermal conductivity typical of MOFs can be improved using a judicious combination of second phase additions and processing techniques. Regarding robustness, we first quantify experimentally the impact of humid air exposure on the properties of MOF-5 as a function of exposure time, humidity level, and morphology (i.e., powders vs. pellets). For humidity levels below 50% only minor degradation is observed for exposure times up to several hours. In

13. Hydrogen Storage Experiments for an Undergraduate Laboratory Course--Clean Energy: Hydrogen/Fuel Cells

ERIC Educational Resources Information Center

Bailey, Alla; Andrews, Lisa; Khot, Ameya; Rubin, Lea; Young, Jun; Allston, Thomas D.; Takacs, Gerald A.

2015-01-01

Global interest in both renewable energies and reduction in emission levels has placed increasing attention on hydrogen-based fuel cells that avoid harm to the environment by releasing only water as a byproduct. Therefore, there is a critical need for education and workforce development in clean energy technologies. A new undergraduate laboratory…

14. Preparation and hydrogen storage properties of Mg2Ni intermetallic nanoparticles

Shao, Huaiyu; Xu, Hairuo; Wang, Yuntao; Li, Xingguo

2004-03-01

In this work we investigated the hydrogen storage properties of stoichiometric Mg2Ni intermetallic nanoparticles produced from Mg and Ni nanoparticles. The mean size of the Mg2Ni particles is about 30-50 nm and the lattice constants of the Mg2Ni compound are a = 5.22 Å, c = 13.29 Å. The Mg2Ni compound showed excellent hydrogen storage properties without activation. It can absorb 2.77, 2.93 and 3.03 wt% hydrogen at 523, 573 and 623 K respectively. After one simple activation process, the obtained Mg2Ni absorbed 1.74, 2.07, 2.31 and 2.82 wt% hydrogen at 293, 348, 426 and 493 K respectively. The absorption and desorption plateau hydrogen pressures are about 2.5 and 0.8 bar at 523 K, 5.9 and 3.4 bar at 573 K and 12.7 and 9.7 bar at 623 K. The resulting van't Hoff equation is log(P/bar) = -3464/T+6.541 and the formation enthalpy (DgrH) and entropy (DgrS) for the Mg2NiH4 are -66.32 kJ/mol H2 and -125.3 J K-1/mol H2.

15. Sputtered Pd as hydrogen storage for a chip-integrated microenergy system.

PubMed

Slavcheva, E; Ganske, G; Schnakenberg, U

2014-01-01

The work presents a research on preparation and physical and electrochemical characterisation of dc magnetron sputtered Pd films envisaged for application as hydrogen storage in a chip-integrated hydrogen microenergy system. The influence of the changes in the sputtering pressure on the surface structure, morphology, and roughness was analysed by X-ray diffraction (XRD), scanning electron microscopy (SEM), and atomic force microscopy (AMF). The electrochemical activity towards hydrogen adsorption/desorption and formation of PdH were investigated in 0.5 M H2SO4 using the methods of cyclic voltammetry and galvanostatic polarisation. The changes in the electrical properties of the films as a function of the sputtering pressure and the level of hydrogenation were evaluated before and immediately after the electrochemical charging tests, using a four-probe technique. The research resulted in establishment of optimal sputter regime, ensuring fully reproducible Pd layers with highly developed surface, moderate porosity, and mechanical stability. Selected samples were integrated as hydrogen storage in a newly developed unitized microenergy system and tested in charging (water electrolysis) and discharging (fuel cell) operative mode at ambient conditions demonstrating a stable recycling performance.

16. Collaborative research on amine borane regeneration and market analysis of hydrogen storage materials.

SciTech Connect

Schubert, David

2010-12-06

Amine borane (AB) is a very high capacity hydrogen storage material that meets DOE gravimetric and volumetric targets for on-board delivery of hydrogen for fuel cell vehicles (FCVs). This research helped make process toward the ultimate goal of practical generation of spent AB and added to the understanding of materials and processes required to utilize AB in practical applications. In addition, this work helped to enhance our fundamental understanding of the properties of boron materials now being pursued for new frustrated Lewis pair catalyst systems for activation of hydrogen and carbon dioxide, of interest for carbon capture and fuels production. This project included four primary areas of investigation: (1) synthesis of borate esters for use as amine borane regeneration intermediates, (2) spent ammonia borane fuel generation and analysis, (3) spent fuel digestion for production of borate esters, and (4) worldwide borate resource analysis. Significant progress was made in each of these areas during the two-year course of this project, which involved extensive collaborations with partners in the Center of Excellence for Chemical Hydrogen Storage, and particularly with partners at the Pacific Northwest National Laboratory. Results of the boron resource analysis studies indicate that sufficient boron reserves exist within the United States to meet forecast requirements for a U.S. fleet of hydrogen FCVs and sufficient resources are available worldwide for a global fleet of FCVs.

17. Wax: A benign hydrogen-storage material that rapidly releases H2-rich gases through microwave-assisted catalytic decomposition

PubMed Central

Gonzalez-Cortes, S.; Slocombe, D. R.; Xiao, T.; Aldawsari, A.; Yao, B.; Kuznetsov, V. L.; Liberti, E.; Kirkland, A. I.; Alkinani, M. S.; Al-Megren, H. A.; Thomas, J. M.; Edwards, P. P.

2016-01-01

Hydrogen is often described as the fuel of the future, especially for application in hydrogen powered fuel-cell vehicles (HFCV’s). However, its widespread implementation in this role has been thwarted by the lack of a lightweight, safe, on-board hydrogen storage material. Here we show that benign, readily-available hydrocarbon wax is capable of rapidly releasing large amounts of hydrogen through microwave-assisted catalytic decomposition. This discovery offers a new material and system for safe and efficient hydrogen storage and could facilitate its application in a HFCV. Importantly, hydrogen storage materials made of wax can be manufactured through completely sustainable processes utilizing biomass or other renewable feedstocks. PMID:27759014

18. Considerations for Storage of High Test Hydrogen Peroxide (HTP) Utilizing Non-Metal Containers

NASA Technical Reports Server (NTRS)

Moore, Robin E.; Scott, Joseph P.; Wise, Harry

2005-01-01

When working with high concentrations of hydrogen peroxide, it is critical that the storage container be constructed of the proper materials, those which will not degrade to the extent that container breakdown or dangerous decomposition occurs. It has been suggested that the only materials that will safely contain the peroxide for a significant period of time are metals of stainless steel construction or aluminum use as High Test Hydrogen Peroxide (HTP) Containers. The stability and decomposition of HTP will be also discussed as well as various means suggested in the literature to minimize these problems. The dangers of excess oxygen generation are also touched upon.

19. Carborane-Based Metal-Organic Framework with High Methane and Hydrogen Storage Capacities

SciTech Connect

Kennedy, RD; Krungleviciute, V; Clingerman, DJ; Mondloch, JE; Peng, Y; Wilmer, CE; Sarjeant, AA; Snurr, RQ; Hupp, JT; Yildirim, T; Farha, OK; Mirkin, CA

2013-09-10

A Cu-carborane-based metal organic framework (MOF), NU-135, which contains a quasi-spherical para-carborane moiety, has been synthesized and characterized. NU-135 exhibits a pore volume of 1.02 cm(3)/g and a gravimetric BET surface area of ca. 2600 m(2)/g, and thus represents the first highly porous carborane-based MOF. As a consequence of the, unique geometry of the carborane unit, NU-135 has a very high volumetric BET surface area of ca. 1900 m(2)/cm(3). CH4, CO2, and H-2 adsorption isotherms were measured over a broad range of pressures and temperatures and are in good agreement with computational predictions. The methane storage capacity of NU-135 at 35 bar and 298 K is ca. 187 v(STP)/v. At 298 K, the pressure required to achieve a methane storage density comparable to that of a compressed natural gas (CNG) tank pressurized to 212 bar, which is a typical storage pressure, is only 65 bar. The methane working capacity (5-65 bar) is 170 v(STP)/v. The volumetric hydrogen storage capacity at 55 bar and 77 K is 49 g/L. These properties are comparable to those of current record holders in the area of methane and hydrogen storage. This initial example lays the groundwork for carborane-based materials with high surface areas.

20. Large-Scale Demonstration of Liquid Hydrogen Storage with Zero Boiloff for In-Space Applications

NASA Technical Reports Server (NTRS)

Hastings, L. J.; Bryant, C. B.; Flachbart, R. H.; Holt, K. A.; Johnson, E.; Hedayat, A.; Hipp, B.; Plachta, D. W.

2010-01-01

Cryocooler and passive insulation technology advances have substantially improved prospects for zero-boiloff cryogenic storage. Therefore, a cooperative effort by NASA s Ames Research Center, Glenn Research Center, and Marshall Space Flight Center (MSFC) was implemented to develop zero-boiloff concepts for in-space cryogenic storage. Described herein is one program element - a large-scale, zero-boiloff demonstration using the MSFC multipurpose hydrogen test bed (MHTB). A commercial cryocooler was interfaced with an existing MHTB spray bar mixer and insulation system in a manner that enabled a balance between incoming and extracted thermal energy.

1. Solid-state structures and properties of scandium hydride; hydrogen storage and switchable mirrors application

2016-05-01

First-principles calculation has been performed on the rare earth hydride ScH2 for hydrogen storage and switchable mirror applications, using the pseudo-potentials and plane waves based on the density-functional theory (DFT). The electronic and structural properties are studied within both local-density and generalized gradient approximations for exchange energy. The formation energy and the optical properties have been investigated and discussed. Our calculated results are generally in good agreement with theoretical and experimental data. Contribution to the topical issue "Materials for Energy Harvesting, Conversion and Storage (ICOME 2015) - Elected submissions", edited by Jean-Michel Nunzi, Rachid Bennacer and Mohammed El Ganaoui

2. Quantifying and Addressing the DOE Material Reactivity Requirements with Analysis and Testing of Hydrogen Storage Materials & Systems

SciTech Connect

Khalil, Y. F.

2012-04-30

The objective of this project is to examine safety aspects of candidate hydrogen storage materials and systems being developed in the DOE Hydrogen Program. As a result of this effort, the general DOE safety target will be given useful meaning by establishing a link between the characteristics of new storage materials and the satisfaction of safety criteria. This will be accomplished through the development and application of formal risk analysis methods, standardized materials testing, chemical reactivity characterization, novel risk mitigation approaches and subscale system demonstration. The project also will collaborate with other DOE and international activities in materials based hydrogen storage safety to provide a larger, highly coordinated effort.

3. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

DOEpatents

Lilga, M.A.; Hallen, R.T.

1991-10-15

The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the product gas from coal gasification processes. 3 figures.

4. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

DOEpatents

Lilga, M.A.; Hallen, R.T.

1990-08-28

The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately [pi]-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancillary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H[sub 2] from mixed gas streams such as the producer gas from coal gasification processes. 3 figs.

5. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

DOEpatents

Lilga, Michael A.; Hallen, Richard T.

1990-01-01

The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the produce gas from coal gasification processes.

6. Bridged transition-metal complexes and uses thereof for hydrogen separation, storage and hydrogenation

DOEpatents

Lilga, Michael A.; Hallen, Richard T.

1991-01-01

The present invention constitutes a class of organometallic complexes which reversibly react with hydrogen to form dihydrides and processes by which these compounds can be utilized. The class includes bimetallic complexes in which two cyclopentadienyl rings are bridged together and also separately .pi.-bonded to two transition metal atoms. The transition metals are believed to bond with the hydrogen in forming the dihydride. Transition metals such as Fe, Mn or Co may be employed in the complexes although Cr constitutes the preferred metal. A multiple number of ancilliary ligands such as CO are bonded to the metal atoms in the complexes. Alkyl groups and the like may be substituted on the cyclopentadienyl rings. These organometallic compounds may be used in absorption/desorption systems and in facilitated transport membrane systems for storing and separating out H.sub.2 from mixed gas streams such as the product gas from coal gasification processes.

7. Effect of hydrogen storage alloy on combustion properties of ammonium perchlorate /glycidylazide polymer -based propellant

Li, G. P.; Dou, Y. M.; Chai, C. P.; Luo, Y. J.

2015-12-01

Hydrogen storage alloys can serve as good potential fuels for propellant design, by improving the energy and combustion properties. The influence of hydrogen storage alloy (A30) on the combustion properties of ammonium perchlorate/glycidylazide polymer (AP/GAP)-based on propellant were studied. The results showed that A30 could increase the burning rate of propellants by 29.75% and 74.78%, compared with B30 and Al. The combustion model of AP/GAP-based propellant containing different fuel was built. Firstly, A30 reduced the high decomposition temperature and promote condensed phase reaction heat of AP. Secondly, A30 deduced the burning surface temperature. Thirdly, A30 might prove the explosive heat of propellant. Therefore, A30 could greatly improve combustion properties of AP/GAP-based propellant.

8. Technical Assessment of Cryo-Compressed Hydrogen Storage Tank Systems for Automotive Applications

SciTech Connect

Ahluwalia, Rajesh; Hua, T. Q.; Peng, J. -K.; Lasher, S.; McKenney, Kurtis; Sinha, J.

2009-12-01

Technical report describing DOE's second assessment report on a third generation (Gen3) system capable of storing hydrogen at cryogenic temperatures within a pressure vessel on-board a vehicle. The report includes an overview of technical progress to date, including the potential to meet DOE onboard storage targets, as well as independent reviews of system cost and energy analyses of the technology paired with delivery costs.

9. Nickel-hydrogen battery design for the Transporter Energy Storage Subsystem (TESS)

NASA Technical Reports Server (NTRS)

Lapinski, John R.; Bourland, Deborah S.

1992-01-01

Information is given in viewgraph form on nickel hydrogen battery design for the transporter energy storage subsystem (TESS). Information is given on use in the Space Station Freedom, the launch configuration, use in the Mobile Servicing Center, battery design requirements, TESS subassembley design, proof of principle testing of a 6-cell battery, possible downsizing of TESS to support the Mobile Rocket Servicer Base System (MBS) redesign, TESS output capacity, and cell testing.

10. Compact fuel cell system utilizing a combination of hydrogen storage materials for optimized performance.

SciTech Connect

Chan, Jennifer P.; Dedrick, Daniel E.; Gross, Karl J.; Ng, Greg L.

2004-12-01

An entirely new class of light-weight reversible hydrides was recently discovered (the Ti-doped alanates)[1]. These NaAIH{sub 4}-based materials have demonstrated reversible hydrogen storage capacities of up to 5 wt%, nearly 4 times the gravimetrically density of commercial metal hydrides. For this reason, they have been considered a breakthrough for hydrogen storage in fuel cell vehicles. This project is the first to publish the use of alanates for the generation of electrical power and the first demonstration of a hydride-fueled elevated-temperature PEM Fuel Cell. Because the kinetics of hydrogen uptake and release by the alanate improves with elevated temperatures, novel concepts were tested for the purpose of developing a highly efficient stand-alone power system. A major focus of this work was on the modeling, design, construction and testing of an integrated fuel cell stack and hydrogen storage system that eliminates the need of complicated heat transfer systems and media. After extensive modeling efforts, a proof-of-concept system was built that employs an integrated fuel cell stack and hydride beds that balancing the generation of fuel cell waste heat with the endothermic release of hydrogen from the alanates. Our demonstration unit was capable of greater than one hour of operation on a single charge of hydrogen from the integrated 173 gram alanate bed. In addition, composite hydride materials with synergistic reaction heats were evaluated and tested to enhance the operational performance of the alanates. The composites provide a unique opportunity to utilize the heat produced from hydriding classic metal hydrides to improve both absorption and desorption rates of the alanates. A particular focus of the mixed storage materials work was to balance the thermodynamics and kinetics of the hydrides for start-up conditions. Modeling of the sorption properties proved invaluable in evaluating the optimum composition of hydrides. The modeling efforts were followed

11. Mechanochemical activation and synthesis of nanomaterials for hydrogen storage and conversion in electrochemical power sources.

PubMed

Wronski, Zbigniew S; Varin, Robert A; Czujko, Tom

2009-07-01

In this study we discuss a process of mechanical activation employed in place of chemical or thermal activation to improve the mobility and reactivity of hydrogen atoms and ions in nanomaterials for energy applications: rechargeable batteries and hydrogen storage for fuel cell systems. Two materials are discussed. Both are used or intended for use in power sources. One is nickel hydroxide, Ni(OH)2, which converts to oxyhydroxide in the positive Ni electrode of rechargeable metal hydride batteries. The other is a complex hydride, Mg(AIH4)2, intended for use in reversible, solid-state hydrogen storage for fuel cells. The feature shared by these unlikely materials (hydroxide and hydride) is a sheet-like hexagonal crystal structure. The mechanical activation was conducted in high-energy ball mills. We discuss and demonstrate that the mechanical excitation of atoms and ions imparted on these powders stems from the same class of phenomena. These are (i) proliferation of structural defects, in particular stacking faults in a sheet-like structure of hexagonal crystals, and (ii) possible fragmentation of a faulted structure into a mosaic of layered nanocrystals. The hydrogen atoms bonded in such nanocrystals may be inserted and abstracted more easily from OH- hydroxyl group in Ni(OH)2 and AlH4- hydride complex in Mg(AlH4)2 during hydrogen charge and discharge reactions. However, the effects of mechanical excitation imparted on these powders are different. While the Ni(OH)2 powder is greatly activated for cycling in batteries, the Mg(AlH4)2 complex hydride phase is greatly destabilized for use in reversible hydrogen storage. Such a "synchronic" view of the structure-property relationship in respect to materials involved in hydrogen energy storage and conversion is supported in experiments employing X-ray diffraction (XRD), differential scanning calorimetry (DSC) and direct imaging of the structure with a high-resolution transmission-electron microscope (HREM), as well as in

12. Development of the ReaxFFCBN reactive force field for the improved design of liquid CBN hydrogen storage materials.

PubMed

Pai, Sung Jin; Yeo, Byung Chul; Han, Sang Soo

2016-01-21

Liquid CBN (carbon-boron-nitrogen) hydrogen-storage materials such as 3-methyl-1,2-BN-cyclopentane have the advantage of being easily accessible for use in current liquid-fuel infrastructure. To develop practical liquid CBN hydrogen-storage materials, it is of great importance to understand the reaction pathways of hydrogenation/dehydrogenation in the liquid phase, which are difficult to discover by experimental methods. Herein, we developed a reactive force field (ReaxFFCBN) from quantum mechanical (QM) calculations based on density functional theory for the storage of hydrogen in BN-substituted cyclic hydrocarbon materials. The developed ReaxFFCBN provides similar dehydrogenation pathways and energetics to those predicted by QM calculations. Moreover, molecular dynamics (MD) simulations with the developed ReaxFFCBN can predict the stability and dehydrogenation behavior of various liquid CBN hydrogen-storage materials. Our simulations reveal that a unimolecular dehydrogenation mechanism is preferred in liquid CBN hydrogen-storage materials. However, as the temperature in the simulation increases, the contribution of a bimolecular dehydrogenation mechanism also increases. Moreover, our ReaxFF MD simulations show that in terms of thermal stability and dehydrogenation kinetics, liquid CBN materials with a hexagonal structure are more suitable materials than those with a pentagonal structure. We expect that the developed ReaxFFCBN could be a useful protocol in developing novel liquid CBN hydrogen-storage materials. PMID:26681481

13. Development of the ReaxFFCBN reactive force field for the improved design of liquid CBN hydrogen storage materials.

PubMed

Pai, Sung Jin; Yeo, Byung Chul; Han, Sang Soo

2016-01-21

Liquid CBN (carbon-boron-nitrogen) hydrogen-storage materials such as 3-methyl-1,2-BN-cyclopentane have the advantage of being easily accessible for use in current liquid-fuel infrastructure. To develop practical liquid CBN hydrogen-storage materials, it is of great importance to understand the reaction pathways of hydrogenation/dehydrogenation in the liquid phase, which are difficult to discover by experimental methods. Herein, we developed a reactive force field (ReaxFFCBN) from quantum mechanical (QM) calculations based on density functional theory for the storage of hydrogen in BN-substituted cyclic hydrocarbon materials. The developed ReaxFFCBN provides similar dehydrogenation pathways and energetics to those predicted by QM calculations. Moreover, molecular dynamics (MD) simulations with the developed ReaxFFCBN can predict the stability and dehydrogenation behavior of various liquid CBN hydrogen-storage materials. Our simulations reveal that a unimolecular dehydrogenation mechanism is preferred in liquid CBN hydrogen-storage materials. However, as the temperature in the simulation increases, the contribution of a bimolecular dehydrogenation mechanism also increases. Moreover, our ReaxFF MD simulations show that in terms of thermal stability and dehydrogenation kinetics, liquid CBN materials with a hexagonal structure are more suitable materials than those with a pentagonal structure. We expect that the developed ReaxFFCBN could be a useful protocol in developing novel liquid CBN hydrogen-storage materials.

14. Curvature and ionization-induced reversible hydrogen storage in metalized hexagonal B{sub 36}

SciTech Connect

Liu, Chun-Sheng Wang, Xiangfu; Yan, Xiaohong; Ye, Xiao-Juan; Zeng, Zhi

2014-11-21

The synthesis of quasiplanar boron clusters (B{sub 36}) with a central hexagonal hole provides the first experimental evidence that a single-atomic-layer borophene with hexagonal vacancies is potentially viable [Z. Piazza, H. Hu, W. Li, Y. Zhao, J. Li, and L. S. Wang, Nat. Commun. 5, 3113 (2014)]. However, owing to the hexagonal holes, tunning the electronic and physical properties of B{sub 36} through chemical modifications is not fully understood. Based on (van der Waals corrected-) density functional theory, we show that Li adsorbed on B{sub 36} and B{sub 36}{sup −} clusters can serve as reversible hydrogen storage media. The present results indicate that the curvature and ionization of substrates can enhance the bond strength of Li due to the energetically favorable B 2p-Li 2p orbitals hybridization. Both the polarization mechanism and the orbital hybridization between H-s orbitals and Li-2s2p orbitals contribute to the adsorption of H{sub 2} molecules and the resulting adsorption energy lies between the physisorbed and chemisorbed states. Interestingly, the number of H{sub 2} in the hydrogen storage medium can be measured by the appearance of the negative differential resistance behavior at different bias voltage regions. Furthermore, the cluster-assembled hydrogen storage materials constructed by metalized B{sub 36} clusters do not cause a decrease in the number of adsorbed hydrogen molecules per Li. The system reported here is favorable for the reversible hydrogen adsorption/desorption at ambient conditions.

15. Effect of Li Adsorption on the Electronic and Hydrogen Storage Properties of Acenes: A Dispersion-Corrected TAO-DFT Study.

PubMed

Seenithurai, Sonai; Chai, Jeng-Da

2016-09-09

Due to the presence of strong static correlation effects and noncovalent interactions, accurate prediction of the electronic and hydrogen storage properties of Li-adsorbed acenes with n linearly fused benzene rings (n = 3-8) has been very challenging for conventional electronic structure methods. To meet the challenge, we study these properties using our recently developed thermally-assisted-occupation density functional theory (TAO-DFT) with dispersion corrections. In contrast to pure acenes, the binding energies of H2 molecules on Li-adsorbed acenes are in the ideal binding energy range (about 20 to 40 kJ/mol per H2). Besides, the H2 gravimetric storage capacities of Li-adsorbed acenes are in the range of 9.9 to 10.7 wt%, satisfying the United States Department of Energy (USDOE) ultimate target of 7.5 wt%. On the basis of our results, Li-adsorbed acenes can be high-capacity hydrogen storage materials for reversible hydrogen uptake and release at ambient conditions.

16. Effect of Li Adsorption on the Electronic and Hydrogen Storage Properties of Acenes: A Dispersion-Corrected TAO-DFT Study

Seenithurai, Sonai; Chai, Jeng-Da

2016-09-01

Due to the presence of strong static correlation effects and noncovalent interactions, accurate prediction of the electronic and hydrogen storage properties of Li-adsorbed acenes with n linearly fused benzene rings (n = 3–8) has been very challenging for conventional electronic structure methods. To meet the challenge, we study these properties using our recently developed thermally-assisted-occupation density functional theory (TAO-DFT) with dispersion corrections. In contrast to pure acenes, the binding energies of H2 molecules on Li-adsorbed acenes are in the ideal binding energy range (about 20 to 40 kJ/mol per H2). Besides, the H2 gravimetric storage capacities of Li-adsorbed acenes are in the range of 9.9 to 10.7 wt%, satisfying the United States Department of Energy (USDOE) ultimate target of 7.5 wt%. On the basis of our results, Li-adsorbed acenes can be high-capacity hydrogen storage materials for reversible hydrogen uptake and release at ambient conditions.

17. Effect of Li Adsorption on the Electronic and Hydrogen Storage Properties of Acenes: A Dispersion-Corrected TAO-DFT Study

PubMed Central

Seenithurai, Sonai; Chai, Jeng-Da

2016-01-01

Due to the presence of strong static correlation effects and noncovalent interactions, accurate prediction of the electronic and hydrogen storage properties of Li-adsorbed acenes with n linearly fused benzene rings (n = 3–8) has been very challenging for conventional electronic structure methods. To meet the challenge, we study these properties using our recently developed thermally-assisted-occupation density functional theory (TAO-DFT) with dispersion corrections. In contrast to pure acenes, the binding energies of H2 molecules on Li-adsorbed acenes are in the ideal binding energy range (about 20 to 40 kJ/mol per H2). Besides, the H2 gravimetric storage capacities of Li-adsorbed acenes are in the range of 9.9 to 10.7 wt%, satisfying the United States Department of Energy (USDOE) ultimate target of 7.5 wt%. On the basis of our results, Li-adsorbed acenes can be high-capacity hydrogen storage materials for reversible hydrogen uptake and release at ambient conditions. PMID:27609626

18. Effect of Li Adsorption on the Electronic and Hydrogen Storage Properties of Acenes: A Dispersion-Corrected TAO-DFT Study.

PubMed

Seenithurai, Sonai; Chai, Jeng-Da

2016-01-01

Due to the presence of strong static correlation effects and noncovalent interactions, accurate prediction of the electronic and hydrogen storage properties of Li-adsorbed acenes with n linearly fused benzene rings (n = 3-8) has been very challenging for conventional electronic structure methods. To meet the challenge, we study these properties using our recently developed thermally-assisted-occupation density functional theory (TAO-DFT) with dispersion corrections. In contrast to pure acenes, the binding energies of H2 molecules on Li-adsorbed acenes are in the ideal binding energy range (about 20 to 40 kJ/mol per H2). Besides, the H2 gravimetric storage capacities of Li-adsorbed acenes are in the range of 9.9 to 10.7 wt%, satisfying the United States Department of Energy (USDOE) ultimate target of 7.5 wt%. On the basis of our results, Li-adsorbed acenes can be high-capacity hydrogen storage materials for reversible hydrogen uptake and release at ambient conditions. PMID:27609626

19. Visualization of a cryogenic jet simulating leak from a liquid hydrogen storage tank

Rose, Tim; Agrawal, Ajay

2009-11-01

Hydrogen is considered an alternative fuel in propulsion and power generation due to fuel economy standards and environmental pollution. However, if an accidental leak were to occur in a hydrogen storage tank, the discharged fuel could find an ignition source and produce an explosion. A barrier wall can be used to contain the leak from the storage tank, therefore protecting equipment and people from the explosion. Past studies have investigated the jet/barrier wall interaction, in a laboratory setting, with fuel stored as a gas. Hydrogen fuel stored as a liquid offers higher energy density. In this work, we have studied the leak at cryogenic conditions due to liquid storage parameters. Jet fluid structure is visualized in a laboratory setting using helium as the supersonic jet fluid. High-speed rainbow schlieren deflectometry (RSD) images are used to show instantaneous flow structure of jet (leakage point) and barrier wall interactions. Results show the jet inlet temperature leads to significant differences in the spread angle and the extent of fuel-air mixture region adjacent to the barrier wall.

20. Hydrogen storage by BeO nano-cage: A DFT study

2016-04-01

First-principles calculations based on density functional theory were performed to study the hydrogen adsorption and H2 storage on the beryllium oxide nano-cage (BeONC). The adsorption of H2 molecules on the nano-cage depends on the polarization and charge of the atom surface. The transfer of charge from the Be atom to its neighboring O atoms in the surface of the cluster indicates the ionic character of the Besbnd O bond, so that Besbnd O bonds are polarized. The results show that the H2 molecule is significantly adsorbed on the BeONC surface, so that the H2 prefers to be adsorbed atop a Be atom as compared to oxygen atoms of the cluster surface. Our calculations also reveal that the gravimetric uptake can overpass the value of 7.6 wt% with an average adsorbed energy (Eads) of -0.11 eV. These findings have important implications on designing of hydrogen storage materials and significantly broadening the spectrum of strategies for fabricating of new nanostructures to enhance hydrogen storage capacity.

1. Preparation and characterization of ordered porous carbons for increasing hydrogen storage behaviors

SciTech Connect

Lee, Seul-Yi; Park, Soo-Jin

2011-10-15

We prepared ordered porous carbons (PCs) by using a replication method that had well-organized mesoporous silica as a template with various carbonization temperatures in order to investigate the possibility of energy storage materials. The microstructure and morphologies of the samples are characterized by XRD, TEM, and FT-Raman spectroscopy. N{sub 2} adsorption isotherms are analyzed by the t-plot method, as well as the BET and the H-K method in order to characterize the specific surface area, pore volume, and pore size distribution of the samples, respectively. The capacity of the hydrogen adsorption of the samples is evaluated by BEL-HP at 77 K and 1 bar. From the results, we are able to confirm that the synthesis of the samples can be accurately governed by the carbonization temperature, which is one of the effective parameters for developing the textural properties of the carbon materials, which affects the behaviors of the hydrogen storage. - Graphical abstract: It is described that the considerable long-range ordering and the presence of mono-dimensional aligned channels between the two aligned nanorods of the porous framework from the SBA-15 was retained in the T-950 sample during the carbonization process. Highlights: > Ordered porous carbons (PCs) are synthesized with various carbonization temperatures by using a replication method. > Carbonization temperature plays an important role in shrinking the micropores during the carbonization process of PCs. > The textural and structural properties of the PCs are good parameters for enhancing the hydrogen storage capacity.

2. Discovery of Novel Complex Metal Hydrides for Hydrogen Storage through Molecular Modeling and Combinatorial Methods

SciTech Connect

Lesch, David A; Adriaan Sachtler, J.W. J.; Low, John J; Jensen, Craig M; Ozolins, Vidvuds; Siegel, Don; Harmon, Laurel

2011-02-14

UOP LLC, a Honeywell Company, Ford Motor Company, and Striatus, Inc., collaborated with Professor Craig Jensen of the University of Hawaii and Professor Vidvuds Ozolins of University of California, Los Angeles on a multi-year cost-shared program to discover novel complex metal hydrides for hydrogen storage. This innovative program combined sophisticated molecular modeling with high throughput combinatorial experiments to maximize the probability of identifying commercially relevant, economical hydrogen storage materials with broad application. A set of tools was developed to pursue the medium throughput (MT) and high throughput (HT) combinatorial exploratory investigation of novel complex metal hydrides for hydrogen storage. The assay programs consisted of monitoring hydrogen evolution as a function of temperature. This project also incorporated theoretical methods to help select candidate materials families for testing. The Virtual High Throughput Screening served as a virtual laboratory, calculating structures and their properties. First Principles calculations were applied to various systems to examine hydrogen storage reaction pathways and the associated thermodynamics. The experimental program began with the validation of the MT assay tool with NaAlH4/0.02 mole Ti, the state of the art hydrogen storage system given by decomposition of sodium alanate to sodium hydride, aluminum metal, and hydrogen. Once certified, a combinatorial 21-point study of the NaAlH4 LiAlH4Mg(AlH4)2 phase diagram was investigated with the MT assay. Stability proved to be a problem as many of the materials decomposed during synthesis, altering the expected assay results. This resulted in repeating the entire experiment with a mild milling approach, which only temporarily increased capacity. NaAlH4 was the best performer in both studies and no new mixed alanates were observed, a result consistent with the VHTS. Powder XRD suggested that the reverse reaction, the regeneration of the

3. On the hydrogen-graphene layers interactions, relevance to the onboard storage problem.

PubMed

Nechaev, Y S; Ochsner, A

2012-10-01

Empirical evaluations of fundamental characteristics of the physical and chemical interaction of hydrogen with graphene layers in different kinds of graphite and novel carbonaceous nanomaterials of graphene layer structure have been carried out. This was done by using the approaches of the thermodynamics of reversible and irreversible processes for analysis of the adsorption, absorption, diffusion, the temperature-programmed desorption (TPD) and other experimental data and comparing such analytical results with first-principles calculations. Such an analysis of a number of the known experimental and theoretical data has shown a real possibility of the multilayer specific adsorption (intercalation) of hydrogen between graphene layers in novel carbonaceous nanomaterials. This is of relevance for solving the bottle-neck problem of the hydrogen on-board storage in fuel-cell-powered vehicles, and other technical applications. PMID:23421196

4. Hydrogen isotope effect on storage behavior of U2Ti and UZr2.3

Jat, Ram Avtar; Sawant, S. G.; Rajan, M. B.; Dhanuskar, J. R.; Kaity, Santu; Parida, S. C.

2013-11-01

U2Ti and UZr2.3 alloys were prepared by arc melting method, vacuum annealed and characterized by XRD, SEM and EDX methods. Hydrogen isotope effect on the storage behavior of these alloys were studied by measuring the hydrogen/deuterium desorption pressure-composition-temperature (PCT) profiles in the temperature range of 573-678 K using a Sievert's type volumetric apparatus. It was observed that, in the temperature and pressure range of investigation, all the isotherms show a single desorption plateau. The PCT data reveals that both U2Ti and UZr2.3 alloys had normal isotope effects on hydrogen/deuterium desorption at all experimental temperatures. Thermodynamic parameters for dehydrogenation and dedeuteration reactions of the corresponding hydrides and deuterides of the above alloys were deduced from the PCT data.

5. Nanoconfinement in activated mesoporous carbon of calcium borohydride for improved reversible hydrogen storage.

PubMed

Comănescu, Cezar; Capurso, Giovanni; Maddalena, Amedeo

2012-09-28

Mesoporous carbon frameworks were synthesized using the soft-template method. Ca(BH(4))(2) was incorporated into activated mesoporous carbon by the incipient wetness method. The activation of mesoporous carbon was necessary to optimize the surface area and pore size. Thermal programmed absorption measurements showed that the confinement of this borohydride into carbon nanoscaffolds improved its reversible capacity (relative to the reactive portion) and performance of hydrogen storage compared to unsupported borohydride. Hydrogen release from the supported hydride started at a temperature as low as 100 °C and the dehydrogenation rate was fast compared to the bulk borohydride. In addition, the hydrogen pressure necessary to regenerate the borohydride from the dehydrogenation products was reduced. PMID:22948563

6. On the hydrogen-graphene layers interactions, relevance to the onboard storage problem.

PubMed

Nechaev, Y S; Ochsner, A

2012-10-01

Empirical evaluations of fundamental characteristics of the physical and chemical interaction of hydrogen with graphene layers in different kinds of graphite and novel carbonaceous nanomaterials of graphene layer structure have been carried out. This was done by using the approaches of the thermodynamics of reversible and irreversible processes for analysis of the adsorption, absorption, diffusion, the temperature-programmed desorption (TPD) and other experimental data and comparing such analytical results with first-principles calculations. Such an analysis of a number of the known experimental and theoretical data has shown a real possibility of the multilayer specific adsorption (intercalation) of hydrogen between graphene layers in novel carbonaceous nanomaterials. This is of relevance for solving the bottle-neck problem of the hydrogen on-board storage in fuel-cell-powered vehicles, and other technical applications.

7. DFT study of hydrogen storage in Pd-decorated C60 fullerene

El Mahdy, A. M.

2015-11-01

Hydrogen storage reactions on Pd-doped C60 fullerene are investigated by using the state-of-the-art density functional theory calculations. The Pd atom prefers to bind at the bridge site between two hexagonal rings, and can bind up to four hydrogen molecules with average adsorption energies of 0.61, 0.45, 0.32, and 0.21 eV per hydrogen molecule. With no metal clustering, the system gravimetric capacities are expected to be as large as 5.8 wt%. While the desorption activation barriers of the complexes nH2 + Pd-C60 with n = 1 are outside the department of energy (DOE) domain (-0.2 to -0.6 eV), the desorption activation barriers of the complexes nH2 + Pd-C60 with n = 2-4 are inside this domain. While the interaction of 1H2 with Pd + C60 is irreversible at 459 K, the interaction of 2H2 with Pd + C60 is reversible at 529 K. The hydrogen storage of the irreversible 1H2 + Pd-C60 and reversible 2H2 + Pd-C60 interactions are characterised in terms of densities of states, infrared, Raman, and proton magnetic resonance spectra, electrophilicity, and statistical thermodynamic stability.

8. Theoretical characterisation of irreversible and reversible hydrogen storage reactions on Ni-doped C60 fullerene

Shalabi, A. S.; El Mahdy, A. M.; Soliman, K. A.; Taha, H. O.

2014-12-01

An attempt has been made to characterise the irreversible and reversible hydrogen storage reactions on Ni-doped C60 fullerene by using the state of the art density functional theory calculations. The single Ni atom prefers to bind at the bridge site between two hexagonal rings of C60 fullerene, and can bind up to four hydrogen molecules with average adsorption energies of -0.85, -0.83, -0.58, and -0.31 eV per hydrogen molecule. No evidence for metal clustering in the ideal circumstances and the hydrogen storage capacity is expected to be as large as 8.9 wt%. While the desorption activation barriers of the complexes nH2NiC60 (n = 1, 2) are outside the desirable energy window recommended by the department of energy for practical applications (-0.2 to -0.6 eV), the desorption activation barriers of the complexes nH2NiC60 (n = 3, 4) are inside this window. The irreversible 2H2 + NiC60 and reversible 3H2 + NiC60 interactions are characterised in terms of several theoretical parameters such as: (1) densities of states and projected densities of states, (2) pairwise and non-pairwise additivity, (3) infrared, Raman, and proton magnetic resonance spectra, (4) electrophilicity, and (5) statistical thermodynamic stability.

9. Performance testing of aged hydrogen getters against criteria for interim safe storage of plutonium bearing materials.

SciTech Connect

Shepodd, Timothy J.; Nissen, April; Buffleben, George M.

2006-01-01

Hydrogen getters were tested for use in storage of plutonium-bearing materials in accordance with DOE's Criteria for Interim Safe Storage of Plutonium Bearing Materials. The hydrogen getter HITOP was aged for 3 months at 70 C and tested under both recombination and hydrogenation conditions at 20 and 70 C; partially saturated and irradiated aged getter samples were also tested. The recombination reaction was found to be very fast and well above the required rate of 45 std. cc H2h. The gettering reaction, which is planned as the backup reaction in this deployment, is slower and may not meet the requirements alone. Pressure drop measurements and {sup 1}H NMR analyses support these conclusions. Although the experimental conditions do not exactly replicate the deployment conditions, the results of our conservative experiments are clear: the aged getter shows sufficient reactivity to maintain hydrogen concentrations below the flammability limit, between the minimum and maximum deployment temperatures, for three months. The flammability risk is further reduced by the removal of oxygen through the recombination reaction. Neither radiation exposure nor thermal aging sufficiently degrades the getter to be a concern. Future testing to evaluate performance for longer aging periods is in progress.

10. Thermodynamically neutral Kubas-type hydrogen storage using amorphous Cr(III) alkyl hydride gels.

PubMed

Morris, Leah; Trudeau, Michel L; Reed, Daniel; Book, David; Antonelli, David M

2015-04-14

In this paper we present amorphous chromium(III) hydride gels that show promise as reversible room temperature hydrogen storage materials with potential for exploitation in mobile applications. The material uses hydride ligands as a light weight structural feature to link chromium(III) metal centres together which act as binding sites for further dihydrogen molecules via the Kubas interaction, the mode of hydrogen binding confirmed by high pressure Raman spectroscopy. The best material possesses a reversible gravimetric storage of 5.08 wt% at 160 bar and 25 °C while the volumetric density of 78 kgH2 m(-3) compares favourably to the DOE ultimate system goal of 70 kg m(-3). The enthalpy of hydrogen adsorption is +0.37 kJ mol(-1) H2 as measured directly at 40 °C using an isothermal calorimeter coupled directly to a Sieverts gas sorption apparatus. These data support a mechanism confirmed by computations in which the deformation enthalpy required to open up binding sites is almost exactly equal and opposite to the enthalpy of hydrogen binding to the Kubas sites, and suggests that this material can be used in on-board applications without a heat management system. PMID:25766409

11. OPTIMIZATION OF INTERNAL HEAT EXCHANGERS FOR HYDROGEN STORAGE TANKS UTILIZING METAL HYDRIDES

SciTech Connect

Garrison, S.; Tamburello, D.; Hardy, B.; Anton, D.; Gorbounov, M.; Cognale, C.; van Hassel, B.; Mosher, D.

2011-07-14

Two detailed, unit-cell models, a transverse fin design and a longitudinal fin design, of a combined hydride bed and heat exchanger are developed in COMSOL{reg_sign} Multiphysics incorporating and accounting for heat transfer and reaction kinetic limitations. MatLab{reg_sign} scripts for autonomous model generation are developed and incorporated into (1) a grid-based and (2) a systematic optimization routine based on the Nelder-Mead downhill simplex method to determine the geometrical parameters that lead to the optimal structure for each fin design that maximizes the hydrogen stored within the hydride. The optimal designs for both the transverse and longitudinal fin designs point toward closely-spaced, small cooling fluid tubes. Under the hydrogen feed conditions studied (50 bar), a 25 times improvement or better in the hydrogen storage kinetics will be required to simultaneously meet the Department of Energy technical targets for gravimetric capacity and fill time. These models and methodology can be rapidly applied to other hydrogen storage materials, such as other metal hydrides or to cryoadsorbents, in future work.

12. Reversible Hydrogen Storage Characteristics of Catalytically Enhanced Ca(Li)-nMg-B-N-H System

Srinivasan, Sesha; Emre Demircak, Dervis; Sharma, Prakash; Yogi, Goswami; Stefanakos, Elias

2013-04-01

The aim of the present investigation is to study the synergistic effects of multi-walled carbon nanotubes, Nb2O5 and other catalysts for reversible hydrogen storage characteristics of Ca(Li)-nMg-B-N-H systems. Multinary hydride using light weight, high capacity hydride compounds such as Ca(BH4)2, LiBH4, LiNH2, nanoMgH2 in 3:1:8:4 composition was synthesized using high energy planetary milling under Ar/H2 ambient. Various nano additives and bi-metallic catalysts were added in a very small concentration with the host hydride (Ca)Li-nMg-B-N-H. The TGA and DSC results demonstrated that the catalytically enhanced Ca(Li)-nMg-B-N-H with hydrogen release at lower temperatures when compared to the pristine systems such as either Ca-Li-B-H or Ca-Li-Mg-B-H. Analyses of metrological characterization using XRD, SEM and have revealed the effectiveness and the role of the catalytic nanoparticles and their enhanced reversible hydrogen storage behavior on the host hydride matrix. The mass spectrometric investigations employing RGA on these nanocrystalline, multi-component hydride systems exhibit the release of hydrogen in major proportion (˜80-90%) as compared to previously attributed ammonia.

13. Thermodynamically neutral Kubas-type hydrogen storage using amorphous Cr(III) alkyl hydride gels.

PubMed

Morris, Leah; Trudeau, Michel L; Reed, Daniel; Book, David; Antonelli, David M

2015-04-14

In this paper we present amorphous chromium(III) hydride gels that show promise as reversible room temperature hydrogen storage materials with potential for exploitation in mobile applications. The material uses hydride ligands as a light weight structural feature to link chromium(III) metal centres together which act as binding sites for further dihydrogen molecules via the Kubas interaction, the mode of hydrogen binding confirmed by high pressure Raman spectroscopy. The best material possesses a reversible gravimetric storage of 5.08 wt% at 160 bar and 25 °C while the volumetric density of 78 kgH2 m(-3) compares favourably to the DOE ultimate system goal of 70 kg m(-3). The enthalpy of hydrogen adsorption is +0.37 kJ mol(-1) H2 as measured directly at 40 °C using an isothermal calorimeter coupled directly to a Sieverts gas sorption apparatus. These data support a mechanism confirmed by computations in which the deformation enthalpy required to open up binding sites is almost exactly equal and opposite to the enthalpy of hydrogen binding to the Kubas sites, and suggests that this material can be used in on-board applications without a heat management system.

14. Hydrogen storage properties of light metal adatoms (Li, Na) decorated fluorographene monolayer.

PubMed

Hussain, T; Islam, M S; Rao, G S; Panigrahi, P; Gupta, D; Ahuja, Rajeev

2015-07-10

Owing to its high energy density, the potential of hydrogen (H2) as an energy carrier has been immense, however its storage remains a big obstacle and calls for an efficient storage medium. By means of density functional theory (DFT) in spin polarized generalized gradient approximation (GGA), we have investigated the structural, electronic and hydrogen storage properties of a light alkali metal (Li, Na) functionalized fluorographene monolayer (FG). Metal adatoms bind to the FG with significantly high binding energy, much higher than their cohesive energies, which helps to achieve a uniform distribution of metal adatoms on the monolayer and consequently ensure reversibility. Due to a difference of electronegativities, each metal adatom transfers a substantial amount of its charge to the FG monolayer and attains a partial positive state, which facilitates the adsorption of multiple H2 molecules around the adatoms by electrostatic as well as van der Waals interactions. To get a better description of H2 adsorption energies with metal-doped systems, we have also performed calculations using van der Waals corrections. For both the functionalized systems, the results indicate a reasonably high H2 storage capacity with H2 adsorption energies falling into the range for the practical applications.

15. Effect of storage and LEO cycling on manufacturing technology IPV nickel-hydrogen cells

NASA Technical Reports Server (NTRS)

Smithrick, John J.

1987-01-01

Yardney Manufacturing Technology (MANTECH) 50 A-hr space weight individual pressure vessel nickel-hydrogen cells were evaluated. This consisted of investigating: the effect of storage and charge/discharge cycling on cell performance. For the storage test the cells were precharged with hydrogen, by the manufacturer, to a pressure of 14.5 psia. After undergoing activation and acceptance tests, the cells were discharged at C/10 rate (5A) to 0.1 V or less. The terminals were then shorted. The cells were shipped to NASA Lewis Research Center where they were stored at room temperature in the shorted condition for 1 year. After storage, the acceptance tests were repeated at NASA Lewis. A comparison of test results indicate no significant degradation in electrical performance due to 1 year storage. For the cycle life test the regime was a 90 minute low earth orbit at deep depths of discharge (80 and 60 percent). At the 80 percent DOD the three cells failed on the average at cycle 741. Failure for this test was defined to occur when the cell voltage degraded to 1 V prior to completion of the 35 min discharge. The DOD was reduced to 60 percent. The cycle life test was continued.

16. Multi-fuel reformers for fuel cells used in transportation: Assessment of hydrogen storage technologies. Phase 1, Final report

SciTech Connect

Not Available

1994-03-01

This report documents a portion of the work performed Multi-fuel Reformers for Fuel Cells Used in Transportation. One objective for development is to develop advanced fuel processing systems to reform methanol, ethanol, natural gas, and other hydrocarbons into hydrogen for use in transportation fuel cell systems, while a second objective is to develop better systems for on-board hydrogen storage. This report examines techniques and technology available for storage of pure hydrogen on board a vehicle as pure hydrogen of hydrides. The report focuses separately on near- and far-term technologies, with particular emphasis on the former. Development of lighter, more compact near-term storage systems is recommended to enhance competitiveness and simplify fuel cell design. The far-term storage technologies require substantial applied research in order to become serious contenders.

17. BC(3) sheet functionalized with lithium-rich species emerging as a reversible hydrogen storage material.

PubMed

Hussain, Tanveer; Chakraborty, Sudip; Kang, T W; Johansson, Börje; Ahuja, Rajeev

2015-02-23

The decoration of a BC3 monolayer with the polylithiated molecules CLi4 and OLi2 has been extensively investigated to study the hydrogen-storage efficiency of the materials by first principles electronic structure calculations. The binding energies of both lithiated species with the BC3 substrate are much higher than their respective cohesive energies, which confirms the stability of the doped systems. A significant positive charge on the Li atom in each of the dopants facilitates the adsorption of multiple H2 molecules under the influence of electrostatic and van der Waals interactions. We observe a high H2 -storage capacity of 11.88 and 8.70 wt % for the BC3 -CLi4 and BC3 -OLi2 systems, respectively, making them promising candidates as efficient energy-storage systems.

18. Effects of reducing temperatures on the hydrogen storage capacity of double-walled carbon nanotubes with Pd loading.

PubMed

Sheng, Qu; Wu, Huimin; Wexler, David; Liu, Huakun

2014-06-01

The effects of different temperatures on the hydrogen sorption characteristics of double-walled carbon nanotubes (DWCNTs) with palladium loading have been investigated. When we use different temperatures, the particle sizes and specific surface areas of the samples are different, which affects the hydrogen storage capacity of the DWCNTs. In this work, the amount of hydrogen storage capacity was determined (by AMC Gas Reactor Controller) to be 1.70, 1.85, 2.00, and 1.93 wt% for pristine DWCNTS and for 2%Pd/DWCNTs-300 degrees C, 2%Pd/DWCNTs-400 degrees C, and 2%Pd/DWCNTs-500 degrees C, respectively. We found that the hydrogen storage capacity can be enhanced by loading with 2% Pd nanoparticles and selecting a suitable temperature. Furthermore, the sorption can be attributed to the chemical reaction between atomic hydrogen and the dangling bonds of the DWCNTs. PMID:24738450

19. First principles DFT investigation of yttrium-decorated boron-nitride nanotube: Electronic structure and hydrogen storage

Jain, Richa Naja; Chakraborty, Brahmananda; Ramaniah, Lavanya M.

2015-06-01

The electronic structure and hydrogen storage capability of Yttrium-doped BNNTs has been theoretically investigated using first principles density functional theory (DFT). Yttrium atom prefers the hollow site in the center of the hexagonal ring with a binding energy of 0.8048eV. Decorating by Y makes the system half-metallic and magnetic with a magnetic moment of 1.0µB. Y decorated Boron-Nitride (8,0) nanotube can adsorb up to five hydrogen molecules whose average binding energy is computed as 0.5044eV. All the hydrogen molecules are adsorbed with an average desorption temperature of 644.708 K. Taking that the Y atoms can be placed only in alternate hexagons, the implied wt% comes out to be 5.31%, a relatively acceptable value for hydrogen storage materials. Thus, this system can serve as potential hydrogen storage medium.

20. Effects of reducing temperatures on the hydrogen storage capacity of double-walled carbon nanotubes with Pd loading.

PubMed

Sheng, Qu; Wu, Huimin; Wexler, David; Liu, Huakun

2014-06-01

The effects of different temperatures on the hydrogen sorption characteristics of double-walled carbon nanotubes (DWCNTs) with palladium loading have been investigated. When we use different temperatures, the particle sizes and specific surface areas of the samples are different, which affects the hydrogen storage capacity of the DWCNTs. In this work, the amount of hydrogen storage capacity was determined (by AMC Gas Reactor Controller) to be 1.70, 1.85, 2.00, and 1.93 wt% for pristine DWCNTS and for 2%Pd/DWCNTs-300 degrees C, 2%Pd/DWCNTs-400 degrees C, and 2%Pd/DWCNTs-500 degrees C, respectively. We found that the hydrogen storage capacity can be enhanced by loading with 2% Pd nanoparticles and selecting a suitable temperature. Furthermore, the sorption can be attributed to the chemical reaction between atomic hydrogen and the dangling bonds of the DWCNTs.
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