Effect of Composition and Atmosphere on Electrical Properties of Donor-doped BaCe 1-(x+y) Zr x Nb y O 3

• Published in: ECS transactions 2013-08, Vol.58 (2), p.147-152
• Main Authors: Gore, Colin M., White, Joseph O., Singh, Harmanpreet, Thangadurai, Venkataraman, Wachsman, Eric D.
• Format: Article
• Language: English
• ISSN: 1938-5862; 1938-6737
• DOI: 10.1149/05802.0147ecst

The properties of donor-doped barium cerate perovskites have recently gained attention as electrode or electrolyte materials for high temperature solid-state devices utilizing CO 2 containing gas streams due to their excellent chemical stability. In this study, the effect of co-doping BaCeO3 with Nb and Zr on electrical conductivity from 300-700 ˚C in air and in H 2 is investigated. Small doping levels give rise to a significant increase in total conductivity in both air and hydrogen environments compared to BaCeO 3 . In air, activation energies for conduction are ~1 eV. In a reducing environment, the Nb appears to be the species more easily reduced in order to give rise to increased total conductivity, and there is a discontinuous change in total activation energy from ~0.55 eV to ~0.3 eV at low temperatures in H 2 . The transition temperature is dependent on dopant concentration. These materials may provide chemically-stable mixed conducting anode materials for high temperature proton conductors.