A density functional theory study on the adsorption and dissociation of N2O on Cu2O(111) surface

Density functional theory has been employed to investigate the adsorption and the dissociation of an N2O at different sites on perfect and defective Cu2O(1 1 1) surfaces. The calculations are performed on periodic systems using slab model. The Lewis acid site, Cu-CUS, and Lewis base site, O-SUF are considered for adsorption. Adsorption energies and the energies of the dissociation reaction N2O -> N-2 + O(s) at different sites are calculated. The calculations show that adsorption of N2O is more favorable on Cu-CUS adsorption site energetically. Cu-CUS site exhibits a very high activity. The Cu-CUS-N2O reaction is exothermic with a reaction energy of 77.45 kJ mol(- 1) and an activation energy of 88.82 kJ mol(-1), whereas the O-SUF-N2O reaction is endothermic with a reaction energy of 205.21 kJ mol(-1) and an activation energy of 256.19 kJ mol(-1). The calculations for defective surface indicate that O vacancy cannot obviously improve the catalytic activity Of Cu2O. (c) 2007 Elsevier B.V. All rights reserved.