Effects of strontium doping on ionic conductivity of Sm2O3-doped ceria (samarium-doped ceria) were investigated. The distribution and average radius of O vacancies by co-doping divalent and trivalent cations were calculated from a hard-sphere model. Experimental results showed that the best conductivity for Ce0.78Sm0.2Sr0.02O1.88 (0.061S/cm) specimen was twice that of Ce0.8Sm0.2O1.9 (0.0371S/cm) at 800C. A decrease of 50C in the working temperature of samarium-doped ceria was developed by modifying the dopant concentration, average binding energy and ionic radius of the dopant. The results confirm the Sm3+ and Sr2+ co-doped ceria material as a potential electrolyte for intermediate-temperature solid oxide fuel cell applications.

Ionic Conductivity Investigation in Samarium and Strontium Co-Doped Ceria System. T.H.Yeh, C.C.Chou: Physica Scripta, 2007, T129, 303-7