sensors. His publications have earned more than 68,000 citations on Google Scholar and a h-index of 120 until September 2015. He has to his credit, two Guinness World Records for creating the smallest brush and the darkest material. Ajayan's team created the darkest known material, a carpet of carbon nanotubes, that reflects only 0.045% of light. In August 2007, he was in the news for creating an energy storage device on a piece of paper, called the paper battery. In a brief interview with Discover Magazine, Ajayan stated he believes the paper battery will have many important future applications in industry and medicine. In 2012, Ajayan's group announced a paint-on battery design, which eventually can eliminate restrictions on the surfaces used for energy storage More recently, Ajayan's group developed a green battery consisting of environmentally friendly lithium-ion cathode, which can lead to the development of completely bio-friendly batteries Ajayan's research group is also focusing on the development of various materials for environmental applications and, last year the group developed a hybrid material capable of effectively removing contaminants from water by coating the sand with carbon. In 2012, Ajayan's group developed a macro-scale carbon nanotube sponge, in which nanotubes are covalently connected each other, and demonstrated its selective absorption of oil from oil-water mixture. Ajayan's present research interests include nanotechnology enabled energy storage devices (battery, supercapacitor and hybrid devices), nanocomposites, layered materials, 3D nanostructured materials, and smart material systems. Apart from leading a research group (~40 people, including post-docs, graduate and undergraduate students, and international visiting scholars), he focuses on teaching and lecturing around the world on nanotechnology. He regularly serves on the advisory board of several materials and nanotechnology journals, nanotechnology startups and international conferences. In his role as an academic at Rice and RPI, Ajayan has been a major promoter of nanotechnology, teaching various interdisciplinary courses at the undergraduate and graduate level, emphasising the changes occurring in the science and engineering curriculum. Constantly travelling to expand the field, Ajayan's group has a large number of collaborators worldwide and he spends a good amount of time abroad and inside the United States. He has visiting Professor positions at various prestigious Universities around the world, such as Tsinghua University (Beijing, China), Indian Institute of Science (Bangalore, India) and Shinshu University (Japan). He was a visiting professor at ISIS, Strasbourg, France for several months during 2003 and a Helmoltz-Humboldt prize winner and