Structure and mixed electronic-ionic conducting properties of La_0.6Sr_0.4Co_1−yFe _yO₃(y=0−1.0) ceramics made by a citrate method

Abstract

La_0.6Sr_0.4Co_1−yFe _yO₃ (y=0−1.0) powders were synthesized by a citrate method, and the structure and mixed electronic-ionic conducting properties of the resulting ceramics were investigated. The synthesized La_0.6Sr_0.4Co_1−yFe _yO₃ powders have a pure perovskite structure and consist of uniform and fine particles. A perovskite structure with rhombohedral symmetry was certified for the La_0.6Sr_0.4Co_1−yFe _yO₃ ceramics. The increase of Co/Fe ratio significantly promoted the grain growth and microstructural densification. The La_0.6Sr_0.4Co_1−yFe _yO₃ compositions with relatively higher Co/Fe ratio exhibit superior mixed conducting properties. The electronic structure and microstructure of the ceramics are responsible for the variation of the mixed conducting properties with Co/Fe ratio.

Keywords

ceramics / oxides / chemical synthesis / microstructure / electrical properties

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