Improved electrochemical oxidation kinetics of La0.5Ba0.5FeO3-δ anode for solid oxide fuel cells with fluorine doping

• DOI: 10.1016/j.jpowsour.2021.230932
• Publication Date: 2021-12-21T10:42:48Z
• Authors: Nianjun Hou; Juanjuan Gan; Qisheng Yan; Yicheng Zhao; Yongdan Li
• Keywords: Anion doping; ta213; Hydrocarbon fuel; Solid oxide fuel cell; 13. Climate action; Lanthanum ferrite; ta215; 01 natural sciences; 7. Clean energy; Anode; 0104 chemical sciences

Funding Information: The financial support from National Natural Science Foundation of China under contract number 22075205 and the support of Tianjin Municipal Science and Technology Commission under contract number 19JCYBJC21700 are gratefully acknowledged. The work has been also supported by the Program of Introducing Talents to the University Disciplines under file number B06006 , and the Program for Changjiang Scholars and Innovative Research Teams in Universities under file number IRT 0641 . Publisher Copyright: © 2021 Elsevier B.V.<br/>Peer reviewed<br/>Sluggish anode kinetics and serious carbon deposition are two major obstacles to developing hydrocarbon fueled solid oxide fuel cells. A highly active and stable perovskite La0.5Ba0.5FeO3-δ anode material is studied in this work. The oxygen surface exchange and charge transfer steps are the rate-determining steps of the anode process, and the former is accelerated with fluorine doping on the anion sites due to the lowering of metal-oxygen bond energy. The oxygen surface exchange coefficients of La0.5Ba0.5FeO3-δ and La0.5Ba0.5FeO2.9-δF0.1 at 850 °C are 1.4 × 10−4 and 2.8 × 10−4 cm s−1, respectively. A single cell supported by a 300 μm-thick La0.8Sr0.2Ga0.8Mg0.2O3-δ electrolyte layer with La0.5Ba0.5FeO3-δ anode shows maximum power densities of 1446 and 691 mW cm−2 at 850 °C with wet hydrogen and methane fuels, respectively, which increase to 1860 and 809 mW cm−2 respectively when La0.5Ba0.5FeO2.9-δF0.1 is used as the anode. The cell exhibits a short-term durability of 40 h using wet methane as fuel without carbon deposition on the anode.<br/>