CuOX/CeO2 Nanocomposites Prepared by Deposition-Precipitation: An XPS Study

Copper oxide/Ceria nanocomposite powders were prepared by a deposition-precipitation procedure. The supporting nanosized ceria was obtained by precipitation at 273 K (in presence of H2O2). The samples are characterized by a nominal (i.e. calculated from the weighted amount of precursors) Cu/Ce wt. ratio of 2% (Accession #1152: CuCe2) and 7% (Accession #1153: CuCe7). The surface properties and the influence of the Cu/Ce atomic ratio were investigated by means of XPS (using a standard Al K alpha source). Besides the wide scan spectra, detailed spectra for the Ce 3d, Ce 4d, Cu 2p and O Is regions and related data are presented and discussed. XP analysis reveals the presence of copper oxide (Cu2O is observed in the sample with lower Cu/Ce wt. ratio whereas Cu is prevalent in the sample richer in Cu). In both the samples, the surface Cu/Ce atomic ratio obtained from XPS data is rather similar: 0.13 (= 0.06 Cu/Ce wt ratio).(C) 2009 American Vacuum Society.