Synthesis and Investigation of Novel Composite Materials Based on the CaO–Bi2O3–Fe2O3 System

The results of the study of novel composite solid electrolytes based on the CаO–Bi 2 O 3 –Fe 2 O 3 system are presented. These materials have a mixed electronic-ionic conductivity which increases with the growth of the Fe 2 O 3 content. In the (СаO) 0.26 (Bi 2 O 3 ) 0.74 –Fe 2 O 3 section, a part of the oxygen-ionic component increases with an increase in the Fe 2 O 3 content and, in contrast, the oxygen conductivity decreases in the (СаO) 0.2 (Bi 2 O 3 ) 0.8 –BiFeO 3 section. These materials are interesting in terms of their use as elements of electrochemical devices, for example, in solid oxide fuel cells, electrolyzers for obtaining extra pure gases (oxygen, hydrogen), and electrochemical oxygen sensors.