Nitrate-citrate Combustion Synthesis and Properties of Ce_(1-x)Gd_xO_(2-x/2) Solid Solutions

摘要

The structure, thermal expansion coefficients, and electric conductivity of Ce_(1-x)Gd_xO_(2-x/2) (x = 0 ~ 0.6) solid solutions, prepared by gel-combustion method, were investigated. The uniform small particle size of the gel-combustion prepared materials allows sintering of the samples into highly dense ceramic pellets at 1300 deg C, a significantly lower temperature, compared to that of 1600~1650 deg C required for ceria solid electrolytes prepared by traditional solid state techniques. XRD showed that single-phase solid solutions have been formed in all investigated range. The maximum conductivity, sigma_(600 deg C) = 5.26 X 10~(-3)S/cm, was found at x = 0.2. The thermal expansion coefficient, determined from high-temperature X-ray data is