Effect of doping with Co2O3, TiO2, Fe2O3, and Mn2O3 on the properties of Ce0.8Gd0.2O2-delta

Russian Academy of Sciences, Moskva, Moscow, Russia
Inorganic Materials (Impact Factor: 0.56). 06/2007; 43(7):735-742. DOI: 10.1134/S0020168507070126


The effects of Co, Fe, Mn, and Ti oxide additions on the sinterability and crystal-chemical, thermal, and electrical properties
of Ce0.8Gd0.2O2−δ have been studied. The results indicate that these oxides enhance the sinterability of the mixed oxide, regardless of whether
they were introduced before or after synthesis. The most effective sintering aid is Co2O3. The lattice parameters of Ce0.8Gd0.2O2−δ samples containing different metal oxide additions (1 mol %) are refined in space group Fm3m. The temperature-dependent thermal expansion data are used to determine the linear thermal expansion coefficients of the
samples. Manganese oxide additions reduce the electrical conductivity of Ce0.8Gd0.2O2−δ, whereas the other dopants increase it in the order Ti < Fe < Co. The activation energy for conduction increases in the order
Co < Ti < Fe < Mn.

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