Features of exchange kinetics of BaFeO3−δ-based triple-conducting materials: current state of research

Abstract

In the preceding decade, significant efforts have been devoted to the development of efficient triple conductivity cathode materials. The study of ion transport mechanisms in mixed H⁺/O²⁻/e⁻ oxides is important for analysing many physical properties of these materials and predicting their changes under the effects of high temperatures. Materials exhibiting triple conductivity represent a novel research area in the development of new high-efficiency electrical energy sources. The materials investigated in this review can be used as electrode materials for various electrochemical devices, such as proton conducting fuel cells, membranes for selective extraction of oxygen or hydrogen from gas mixtures, membranes for separation of gas mixtures. This review presents the developments of cathode materials with triple conductivity. The focus of this work is on cathode materials based on BaFeO_3−δ oxide, which possess triple conductivity due to cation and anion doping. The review further discusses recent advancements in cathode material development, encompassing the reaction mechanism, the fundamental characteristics of cathode materials, control strategies, and the determination of each type of conductivity. Finally, the review concludes with a discussion of the current challenges and future directions in research in this field.