| 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.)... |
