The crystal structure and electrical conductivity of proton conducting Ba0.6Sr0.4Zr1 − yYyO3 − δ

The phase transition, thermal expansion property, sintering property and electrical conductivity of Ba0.6Sr0.4Zr1 − yYyO3 − δ have been investigated. Crystal structure of Ba0.6Sr0.4Zr1 − yYyO3 − δ (0.0 ≤ y ≤ 0.2) at room temperature is tetragonally distorted perovskite. The temperature of the second order phase transition from tetragonal to cubic gradually increased with increasing Y content, which affected thermal expansion coefficient. High sintering property was maintained regardless of Y content and Ba0.6Sr0.4Zr0.9Y0.1O3 − δ showed the highest proton conductivity among Ba0.6Sr0.4Zr1 − yYyO3 − δ (0.0 ≤ y ≤ 0.2), which was relatively high among so far reported proton conductivity in BaZr1 − xYxO3 − δ or SrZr1 − xYxO3 − δ system.