Introduction of In or Ga as second dopant to BaZr0.9Y0.1O3 − δ to achieve better sinterability

BaZr1 − xYxO3 − δ is a proton-conducting oxide that has both high ionic conductivity and good chemical stability, but disadvantageously has low sinterability. In this work, two co-dopant systems, BaZr0.9(Y1 − xMx)0.1O3 − δ (M = Ga, In), were studied with the aim of improving sinterability. In both systems, sinterability was markedly improved. Although the addition of Ga markedly decreased the conductivity of BaZr1 − xYxO3 − δ, the addition of In did not decrease the conductivity significantly. It was shown that BaZr0.9Y0.05In0.05O3 − δ is a practically useful material with a good combination of conductivity and sinterability.