Density functional and bonding study of hydrogen and platinum adsorption on B2-FeTi (111) slab

We performed a density functional theory study (DFT) of hydrogen interaction with Pt on the B2-FeTi (111) surface. The DFT is employed to trace the relevant orbital interactions and to discuss the electronic changes of incorporating H on the Fe–Ti bonding. We determined the optimal location for Pt and then for adsorbed hydrogen. We also followed the density of states and the changes in the chemical bonding for both adsorbed atoms on the surface. The overlap population analysis reveals metal–metal bond breaking after hydrogen adsorption, being this bond the more affected.

► After H adsorption, the H–Ti and H–Fe interaction are both bonding.
► When Pt is adsorbed, the Fe–Fe bond is also weakened and a Pt–Fe bond is formed at the expense of irons bonds.
► The adsorption energy indicates a strong Pt-surface interaction close to that reported in the literature.
► In the case of co-adsorption, Pt makes a 17% stronger bond for the metal–H interaction.
► The OPDOS curves shows that all the bonds have a main bonding area, being higher for the Pt–Fe and the Pt–Ti bond.