Associative oxygen species on the oxidized silver surface formed under O microwave excitation

The experimental methods of X-ray and ultraviolet photoelectron spectroscopies XPS and UPS, respectively.and the quantum mechanical calculations are applied for analysis of oxygen states on the silver oxide surface. At low temperatures T-470 K., the silver surface is intensively oxidized by a microwave oxygen discharge to form cuprite Ag2O. Two adsorbed oxygen species of the atomic dissociative.and molecular associative. nature can be adsorbed on the cuprite Ag2O surface. A comparison of the UPS data and the DFT calculations of molecular models Ag2–O2and Ag2–O3shows that the formation of ozonide-like structures is preferable to that of peroxide species. Thermal stability and the reaction probability of the adsorbed states are investigated. q2000 Elsevier Science B.V. All rights reserved.