Dissociative adsorption of H2 on metal cluster and (1 1 1) surface of Ag, Co, Cu and Ru

Abstract

Dissociative adsorption of H2 was carried out on the @13 cluster (@ = Ag, Co, Cu and Ru) according to the number of nH2 molecules (n = 1–10) and it was compared with H2 adsorption on the surface (1 1 1) of the same metals using Density Functional Theory. The adsorption of H2 is energetically more favorable on the @13 clusters than on the surfaces for all metals studied. Charge population analysis and density of states were calculated to understand the electronic behavior of hydrogen on the @13 cluster and on the (1 1 1) surface. In all the cases studied, hydrogen takes more charge from the @13 metal cluster than on (1 1 1) surfaces. The ab-initio thermodynamics shows the favorable ranges of pressure, energy, and chemical potential for dissociative adsorption of H2 for all the coverages studied on the metal clusters. Additionally, XPS and chemisorption results for supported nanoparticles and bulk material are presented for cobalt.