The catalytic effect of transition matel doped Al (111) surfaces for hydrogen splitting

Abstract

To investigate the catalytic activity of transition metals in hydrogenation process, the density-functional method has been performed to study the hydrogen interaction with metal-doped Al (111) surfaces. Results indicate that Al (111) surfaces doped with Sc, V, Fe, or Ti atom can effectively enhance hydrogenation reaction. H2 dissociation barriers on Sc, V, Fe and Ti doped surfaces are 0.54 eV, 0.29 eV, 0.12 eV, and 0.51 eV respectively, while diffusion barrier for H atom away from the Sc, V, and Ti doped surfaces are 0.51 eV, 0.66 eV, and 0.57 eV correspondently. Especially, V doped Al (111) surface has shown an amazing catalytic hydrogenation performance for the lower activating energy and diffusion barrier. Moreover, the metal atoms tend to be uniformly distributed on the Al (111) surface. And increasing the number of doping metal atoms, the catalytic performance are similar to that of the isolated transition metal atom doped Al (111) surface. This research may provide a reference to study the metal activity of hydrogen reuptake for NaAlH4.