Advanced materials for SOFC application: Strategies for the development of highly conductive and stable solid oxide proton electrolytes

The basic strategies of improving the stability of proton-conducting electrolytes based on barium cerate (BaCeO3) by means of: (i) co-doping, (ii) doping by nonmetallic elements and (iii) composites development, are considered in the present review work. The reasons of the stability enhancement in these systems, as well as the correlation between stability and electrical conductivity are also presented and discussed. On the base of literature data comparative analysis, the electrolytes with sufficient phase structural, chemical, thermal stabilities and acceptable conductivity are identified.