Synthesis and characterization of Cu-doped ceria nanopowders

Nanopowdered solid solution Ce1−xCuxO2−γ samples (0 ≤ x ≤ 0.15) were synthesized by self-propagating room temperature synthesis (SPRT). Raman spectroscopy and XRD at room temperature were used to study the vibration properties of these materials as well as the Cu solubility in ceria lattice. The solubility limit of Cu2+ in CeO2 lattice was found to be lower than published in the literature. Results show that obtained powders with low dopant concentration are solid solutions with a fluorite-type crystal structure. However, with Cu content higher than 7.5 mass%, the phase separation was observed and two oxide phases, CeO2 and CuO, coexist. All powders were nanometric in size with high specific surface area.