General trends in CO dissociation on transition metal surfaces

摘要

Dissociative adsorption is one of the most important reaactions in catalysis. In this communication we propose a model aiming to generalize the important factors that affect dissociation reactions. Specifically, for a dissociation reaction, say AB -> A + B, the model connects the dissociation barrier with the association barrier, the chemisorption energies of A and B at the final state and the bonding energy of AB in the gas phase. To apply this model, we have calclated CO dissociation on Ru(0001), Rh(111), (4d transition metals), Os(0001), Ir(111), and Pt(111) (5d transition metals) using density function theory (DFT). All the barriers are determined. We find that the DFT results can be rationalized within the model. The model can also be used to expalin many experimental observations.