Effects of Strontium Content on the Microstructure and Ionic Conductivity of Samarium-Doped Ceria

Due to its high oxygen ion conductivity at elevated temperatures, samarium-doped ceria (SDC) is a very promising material for application in solid state electrochemical devices and especially the electrolytes of oxide fuel cells. Several prior studies have reported further improvement ionic SDC on doping with small amounts strontium. It suggested that strontium acts as sintering aid—improving microstructure SDC—and scavenger silicon impurities, decreasing tendency form resistive phases grain boundaries. However, because range preparation methods resulting differences levels, some inconsistencies exist literature. Furthermore, effect intrinsic (bulk) not often discussed. To address these issues, systematic, combined microstructural study has been performed compositional series contents, Ce0.8−xSm0.2SrxO2−δ (x = 0, 0.002, 0.005, 0.01, 0.02, 0.03, 0.04). A low temperature synthesis affording products was employed. Total bulk boundary data were obtained over wide range. Increasing content caused general decrease total conductivity, but there an lowest levels. These results interpreted by reference microstructures using, among other parameters, blocking, normalised factors.