Detection of adsorbed O2− species on CeO2 solid impregnated with Ag2+ ions during its thermal treatment under a H2 atmosphere, an EPR study

Abstract

10% Ag/CeO₂ solid was prepared by the impregnation method. When the solid is calcined at 400 °C, three types of Ag²⁺ species are formed. One of them is more thermally stable compared to the others. The adsorption on the solid of O₂ or H₂ molecules gives an adsorbed O₂⁻ species on the surface, detected by electron paramagnetic resonance (EPR). The mobility of oxygen in CeO₂ and the nature of cations loaded on this support can be the origin of the adsorbed O₂⁻ species particularly when the solid is treated under H₂ molecules.