Abstract: The adsorption and dissociation of two NO molecules on Cu2O(111) surface have been studied with periodic slab model by DFT method using the generalized gradient approximation(GGA) with the Perdew-Burke-Emzerhof(PBE) exchange-correlation functional. Three kinds of structures, Cu+(NO)(NO), Cu+(NO)(ON), and Cu+(ON)(ON), with singlet and triplet states, were considered. Their corresponding adsorption energies and Mulliken charges were calculated. The calculated results indicate that in the optimized Cu+(ON)(ON) configuration, two adsorbed NO molecules form a dimeric species with a much shorter N—N bond length (about 124.4 pm). Such a configuration contributes to the dissociation of NO to Cu-O surface species, with elimination of N2 or N2O.

Key words: Density functional theory, Periodic slab model, NO, Cu2O(111), Adsorption, Dimer, Dissociation