Enhancing oxygen reduction reaction activity of perovskite oxides cathode for solid oxide fuel cells using a novel anion doping strategy

Possessing a high oxygen reduction reaction (ORR) activity is one of the most important prerequisites for the cathode to ensure an efficient solid oxide fuel cell. Herein, a highly active cathode is developed by doping the fluorine anion in anion sites of perovskite oxides (ABO(3)). The electrocatalytic activities of three different cathode samples including the original perovskite La0.6Sr0.4Co0.2Fe0.8O3-delta (LSCF), the doped La0.6Sr0.4Co0.2Fe0.8O2.95-delta F0.05 (LSCFF0.05) and La0.6Sr0.4Co0.2Fe0.8O2.9-delta F0.1 (LSCFF0.1) are comparatively investigated. The fluorine doped perovskites reveal higher electrochemical performance than the original perovskite. Based on three cathodes of LSCF, LSCFF0.05 and LSCFF0.1 operated at 850 degrees C, the measured area specific resistance was 0.018, 0.017 and 0.91 Omega cm(2), respectively; and the respective maximum power density of the single fuel cell using the 9-mu m-thick YSZ electrolyte was 754, 1005, and 737 mW cm(-2). Such performance results vividly indicate that, the obtained perovskite oxyfluoride by doping an optimum amount of F ions can efficiently improve ORR activity and thus is a feasible strategy to develop cathode for highperformance solid oxide fuel cells. (C) 2018 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.