Chemical and electrical properties of BaPr0.7Gd0.3O3−δ

Doped perovskites have a growing interest as electrolytes for IT-SOFCs. In the search for proton conducting electrolytes, Gd-doped BaPrO3 was studied. The present work reports the chemical stability and electrical conductivity of BaPr0.7Gd0.3O3−δ powders. This system is found to be highly reactive under water, CO2 and hydrogen containing atmospheres. Comparison of the conduction behaviour measured at different atmospheres indicates that the system behaves as a p-type electronic conductor. The total conductivity is about 1 × 10−3 S cm−1 at 300 °C, in dry O2. The resistance of the system seems to be dominated by the grain boundary contribution. However, structure investigation reveals there is a gadolinia segregation, which may act as a resistive barrier. The material is not suitable for SOFC applications due to its low stability.