CO OXIDATION ON PT(111) - AN AB-INITIO DENSITY-FUNCTIONAL THEORY STUDY

CO oxidation on Pt(111) is studied with ab initio density functional t heory. The low energy pathway and transition state for the reaction ar e identified. The key event is the breaking of an O-metal bond prior t o the formation of a chemisorbed CO2 molecule. The pathway can be rati onalized in terms of competition of the O and C atoms for bonding with the underlying surface, and the predominant energetic barrier is the strength of the O-metal bond.