Atomic and electronic structure dependence of surface chemical reactivity

P. LEGARÉ; G.F. CABEZA; N.J. CASTELLANI

Tamanrasset (Argelia)

Congreso; Colloque Scientifique Algéro-Français, TAN-MAT 2003, Les matériaux émergents,; 2003

The chemical properties of Pt deposits on Co(0001) in the range of Pt coverage up to 1.5 monolayer are presented. They are checked by CO adsorption at room temperature. We show that the CO total coverage decrease as the Pt coverage although both the (apparently) free Co areas, as well as the Pt-covered areas do adsorb CO. This is a consequence of the CO adsorption energy lowering. This is explained by the observations performed by STM, LEED and photoemission on the Pt-covered surface, before and after CO exposure. Ab initio calculations performed on a Pt monolayer on Co(0001) confirm the interpretation.