Study on stability and electrical performance of yttrium and bismuth co-doped BaCeO3

Yttrium and bismuth co-doped BaCeO3 (BaCe0.8−xY0.2BixO3−δ, x=0, 0.1, 0.3, 0.5, abbreviated as B0, B10, B30, B50, respectively) powders were successfully synthesized by the citrate–EDTA auto-ignition method and dense ceramics were also obtained. The investigations were mainly focused on the chemical stability and electrical performance of the bismuth doped BaCe0.8Y0.2O3−δ. The phase and thermal analysis of the powders demonstrated that the appropriate amount of Bi dopant can well stabilize BaCeO3 (e.g. Bi=0.3 and 0.5) and prevented them from boiling water damage, whilst the stability in CO2-containing atmosphere degraded with the increase of the bismuth content. It was demonstrated that in wet air, the conductivities of B30 and B50 reached as high as 0.20 S/cm and 0.71 S/cm at 700 °C, respectively. And both were one order of magnitude higher than that of B0. An electron conduction mechanism for the bismuth doped BaCeO3 specimen was proposed. Yttrium and bismuth co-doping exerted influences on both the chemical stability and electrical performance.