Density functional theory calculations of hydrogen dissociative adsorption on platinum-involved alloy surfaces

Density functional theory calculations of the H2 molecule over the Pt(111), Pt4Pd5(111), Pt3Ir6(111), and Pt8Ru1(111) surfaces were carried out to derive key properties involving interactions and electronic state of each atom. From the calculations, H2 dissociative adsorption shows the lowest barrier in case of the Pt3Ir6(111) surface. Pt4Pd5(111) and Pt8Ru1(111) surfaces show a small energy barrier, while the Cu(111) surface is the highest energy barrier. The difference in the reactivity of H2 molecule with the surface is pointed out by the differences in the valence electron configuration of approaching hydrogen which is also verified from the density of state curve. The electronic structure plots illustrate the substituted atoms can interact with molecular H2 projected on the surface d-orbital.