Oxygen diffusion and electrochemical performance of La0.6−xSr0.4BaxCo1−yFeyO3−δ

• Published in: Journal of materials science. Materials in electronics 2019-11, Vol.30 (22), p.20050-20057
• Main Authors: Zhang, Huanhuan, Zhao, Lei, Jian, Binghua, jin, Jiang, Zhang, Hua
• Format: Article
• Language: English
• Subjects: Barium; Characterization and Evaluation of Materials; Chemistry and Materials Science; Crystal structure; Diffusion; Doping; Electrochemical analysis; Electrochemical impedance spectroscopy; Electrode polarization; Electrodes; Electrolytes; Free energy; Glycine; Heat of formation; Iron; Materials Science; Maximum power density; Nitrates; Optical and Electronic Materials; Oxygen; Vacancies
• ISSN: 0957-4522; 1573-482X
• DOI: 10.1007/s10854-019-02376-9

La 0.6−x Sr 0.4 Ba x Co 1−y Fe y O 3−δ (x = 0, 0.2, y = 0.1, 0.2, 0.3, 0.4) were prepared by the glycine–nitrate process. The electrochemical property and oxygen diffusion behavior of La 0.6−x Sr 0.4 Ba x Co 1−y Fe y O 3−δ were investigated. The electrochemical impedance spectroscopy analysis suggests that doping with an appropriate amount of iron and barium improves the catalytic performance. La 0.4 Sr 0.4 Ba 0.2 Co 0.9 Fe 0.1 O 3−δ calcined at 950 °C exhibits the minimum polarization resistance of 0.0349 Ω cm 2 at 750 °C. The doping of Fe improves the sintering performance. The crystalline size of La 0.6−x Sr 0.4 Ba x Co 1−y Fe y O 3−δ becomes smaller with the doping amount of Ba, which increase the number of active sites. The doping of Ba decreases the oxygen vacancy formation energy and increases the oxygen vacancy concentration, which accelerates the oxygen diffusion. Further, the single cell performance for La 0.4 Sr 0.4 Ba 0.2 Co 0.9 Fe 0.1 O 3−δ as cathode shows the maximum power density of 539.49 W cm −2 at 750 °C.