Synthesis and characterization of Ag/CeO_2 nanocomposites

摘要

Two Ag/CeO_2 nanocomposite samples were prepared by deposition-precipitation (Ag/Ce nominal atomic ratio = 0.03 and 0.12). XPS data suggest the possible presence of traces of Ce(III). Beside Ag (0), oxidized silver species are also revealed in the Ag/CeO_2 sample with lower metal content. The deposition of metal increases surface hydroxylation and carbonation. Methanol interacts molecularly and dissociatively with the samples; oxidation products are observed from low temperature and depend on Ag content. Both the samples reveal a high activity in methanol complete oxidation; traces of partial oxidation products are observed in the sample with lower Ag content.