EMF-MEASUREMENTS ON NANOCRYSTALLINE COPPER-DOPED CERIA

Mixed oxide samples of nanostructured CuxCe1-xO2-y of various composit ion were generated by (i) chemical precipitation and ball milling and (ii) inert gas condensation. X-ray diffraction measurements suggested that copper oxide was dissolved in nanostructured cerium oxide up to c oncentrations of x = 11.15. Solid electrolyte cells of the type A, Cu2 O/CuBr/CuxCe1-xO2-y (A = Cu or CuO) showed reversible cell voltages. T he ratio of the formal chemical activities of CuO and Cu2O dissolved i n nanostructured cerium oxide were calculated from the cell voltages. The results are discussed in terms of an apparent macroscopic solubili ty, due to interfacial segregation of copper oxide on nanostructured c erium oxide. (C) 1998 Academic Press.