A DFT study of hydrogen chemisorption on V (100) surfaces

摘要

In this study, hydrogen adsorption on the surface of vanadium at various positions (top, bridge, and central sites) was studied, and the binding energies of hydrogen species adsorbed on vanadium were calculated using density functional theory (DFT) within the generalized gradient approximation (GGA). The potential of the adsorption of hydrogen on vanadium was examined as a function of both surface coverage and adsorption site. Our results were in excellent agreement with the experimental values reported in the literature. The relative stabilities of hydrogen chemisorption were independent of both the transition metal surface and surface coverage. That is, hydrogen exhibited insignificant selectivity with respect to positions on the metal surface. Our data on H-2/V surface chemisorption revealed that the stablest model for hydrogen adsorption was that on the vertical bridge site. The adsorption energy for this model was lower than for the other sites. However, adsorption on bridge-hydrogen vacancies was strong.