Samarium and dysprosium doped strontium cobalt oxide cathode ceramics for use in intermediate temperature solid oxide fuel cells

Samarium and dysprosium doped strontium cobaltites were synthesized and characterized to determine the optimal composition for intermediate temperature solid oxide fuel cell (SOFC) cathode materials. Ceramic powders with compositions Sm(1-x)SrxCoO3-delta and Dy (1-x)SrxCoO3-delta for x = 0.1, 0.3, 0.5, 0.7, 0.9 were synthesized via the glycine nitrate process and isostatically pressed prior to sintering in order to obtain samples with relative densities greater than 95%. The sintering properties and microstructure of the formed samples were identified in order to optimize the results obtained for thermal expansion coefficients, electrical conductivities, and area specific resistances.; Electrical conductivities of more than 1500 S/cm were achieved for the composition Sm0.7Sr0.3CoO3-delta over the temperature range 500°C--700°C. The electrical conduction behaviour transitioned from semi-conducting to metallic between a strontium content of x = 0.1 and x = 0.3. (Abstract shortened by UMI.)...