Electrochemical water splitting is a potentially carbon-neutral method of splitting water into gaseous H2 fuel and O2 via electrical energy from renewable sources. H2O is oxidized to O2 in the Oxygen Evolution Reaction (OER) at the anode and reduced to H2 in the Hydrogen Evolution Reaction (HER) at the cathode. Electrochemical H2 production is generally performed entirely in alkaline media but HER is much more favorable in acidic media. Alkaline conditions are preferred at the anode as OER is generally more favorable in basic media. To achieve the greatest activity, a Proton-Exchange Membrane (PEM) must separate the two electrolytes and allows protons to flow from the anode to the cathode. The economics associated with PEMs, precious metal catalysts, and catalyst stability have led to widespread use of alkaline single electrolyte devices without expensive membranes or noble metal catalysts. The search space for such catalysts is much greater due to the greater stability of alkaline conditions. Various types of catalysts have been investigated from transition metal alloys, compounds (carbides, phosphides, chalcogenides) and their heterostructures. Particular attention has been paid to inexpensive Ni-based catalysts, especially binary compounds of Ni. In addition, the understanding of the origin of such success has been limited. Theoretical analyses of HER catalysis focuses on the free energy of hydrogen adsorption, ΔGH* determining reactivity. By the Sabatier principle, the reactive intermediate H* has an optimum binding energy that is neither too strong nor too weak. This is the basis of the so-called "Volcano relation" of The correlation between activity and ΔGH* has been used extensively in acid, as it captures the rate-determining step (RDS) of H adsorption/reduction. In alkaline media, catalysts suffer a ~2-3 order of magnitude decrease in activity which is not explained by shifts in ΔGH*. Proposed origins for lower alkaline activity are of two types: increased difficulty of water dissociation and increased energy associated with interfacial reorganization. The former originates from the greater O-H bond energy of H2O compared to that of H3O + . The sluggish H2O dissociation kinetics are thought to limit the Volmer step and make it ratelimiting. In 2016, Rossmeisl et al proposed that decreased HER activity in alkaline media was not a surface interaction, but due to reorganization of the double layer upon proton transfer to the surface from bulk. They further explained that this barrier originates from the entropy loss of a proton entering the well-structured Outer Helmholtz Layer (OHL), which has a configuration dependent on the surface itself. This idea was developed further by Koper et al by relating entropy change to the strength of the interfacial electric field and ultimately the Potential of Zero Charge (PZC). A recent models Koper have integrated the OH binding energy into previous ΔGH* correlations to explain alkaline HER on metal surfaces. The structure of the electrochemical interface and its influence on reaction barriers has been left relatively unexplored, especially in the case of composite materials. Previous studies that explicitly include the solvent do so using static calculations with the system following an energy minimum along the reaction path. Such investigations entirely neglect the role of interface dynamics on the reaction and instead use the solvent as a Helmholtz layer and source of hydrogen bonds, while assuming perfect solvation. In recent years, significant effort has been dedicated to understanding the dynamics and influence of the metal-water interface. The group of Groß et al. has performed much of the foundational work on the structure of the metal-water interface at finite temperature. They first established that the extent of order in the electrical double layer varies with metal on close-packed (111) surfaces using Ab Initio Molecular Dynamics (AIMD) simulations. Later studies found differences in hydrogen bonding above the noble metal (111) surfaces. Groß and Sakong recently outlined the structure of the electrochemical interface on Pt (111), addressing the effect of pH, charging, and HER adsorbates. Despite this diagnosis of the interface, studies have yet to attempt directly ascertaining the influence of interface dynamics on the alkaline Volmer reaction. With recent advances in computing, advanced sampling techniques are just beginning to allow for a quantification of the entropic contributions to barrier energies that cannot be measured in the single-point calculations. In this work, we revisit the Volmer step under alkaline conditions using both static and AIMD simulations. We begin with a look at what a Ni surface might look like under active conditions. Revisiting a previous publication, we show that Ni/Ni3S2 composite catalysts may result in a S-modified Ni interphase. We further use GCDFT calculations to show that unmodified Ni will be covered by a small amount of *OH, in contrast to Pt. However, the energetics on these surfaces with light coverage do not explain the disparities in reactivity. Further investigation of the Volmer barrier at potential shows that these modifications do not significantly change charging behavior of the catalyst. Having dismissed the energetic explanation, we use Car-Parinello molecular dynamics combined with metadynamics sampling to estimate the Volmer step barrier on pristine and modified metal surfaces. These barriers are contrasted with those obtained using static (NEB) calculations to quantify the entropic contributions to the barrier. Finally, these entropic "penalties" are explained as function of the interface structure through analysis of unbiased AIMD simulations. We conclude that the consistency of interfacial solvation governs the Volmer barrier under dynamics.