Enhanced sintering behavior mechanism of nanocrystalline BaCe0.8Sm0.2O3−δ by Cu doping

Nano-sized BaCe0.8Sm0.2O3−δ and Cu-doped BaCe0.8Sm0.2O3−δ proton conducting electrolyte powders are synthesized by citric-nitrate method, and then the powder properties are investigated. The synthesized BaCe0.8Sm0.2O3−δ powder acquires pure perovskite structure after heat treatment above 1100 °C, while impurity phases such as BaCO3 and Ce0.8Sm0.2O2−δ are formed below 1100 °C. The BaCe0.8Sm0.2O3−δ and Cu-doped BaCe0.8Sm0.2O3−δ showed similar powder characteristics, except the shrinkage rate. The sintering temperature for densification of the synthesized BCS are significantly reduced as much as ∼300 °C by small amount of Cu. Compared to drastic reduction in sintering temperature, the total conductivity and the activation energy of Cu doped BCS turn out to deviate negligibly from those of pure BCS.