Epitaxially Grown Heterostructured SrMn3O6−x‐SrMnO3 with High‐Valence Mn3+/4+ for Improved Oxygen Reduction Catalysis

• Published in: Angewandte Chemie International Edition Vol. 60; no. 40; pp. 22043 - 22050
• Main Authors: Chen, Cheng, Wang, Xiao‐Tong, Zhong, Jia‐Huan, Liu, Jinlong, Waterhouse, Geoffrey I. N., Liu, Zhao‐Qing
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 27.09.2021
• Edition: International ed. in English
• Subjects: Air batteries; Catalysis; Catalysts; Catalytic activity; Charge transfer; Chemical reactions; Chemical reduction; Electrocatalysts; Electrochemistry; Electrodes; Epitaxial growth; Heterojunctions; Heterostructures; Interfacial properties; Intermediates; Oxygen; oxygen reduction reaction; Oxygen reduction reactions; perovskites; Rechargeable batteries; Strontium oxides; zinc-air batteries
• ISSN: 1433-7851; 1521-3773
• DOI: 10.1002/anie.202109207

Heterostructured catalysts show outstanding performance in electrochemical reactions owing to their beneficial interfacial properties. However, the rational design of heterostructured catalysts with the desired interfacial properties and charge‐transfer characteristics is challenging. Herein, we developed a SrMn3O6−x‐SrMnO3 (SMOx‐SMO) heterostructure through epitaxial growth, which demonstrated excellent electrocatalyst performance for the oxygen reduction reaction (ORR). The formation of high‐valence Mn3+/4+ is beneficial for promoting a positive shift in the position of the d‐band center, thereby optimizing the adsorption and desorption of ORR intermediates on the heterojunction surface and resulting in improved catalytic activity. When SMOx‐SMO was applied as an air‐electrode catalyst in a rechargeable zinc‐air battery, a high output voltage and power density was achieved, with performance comparable to a battery prepared with Pt/C‐IrO2 air‐electrode catalysts, albeit with much better cycling stability. An epitaxially grown SrMn3O6−x‐SrMnO3 heterostructure has been developed for the oxygen reduction reaction (ORR). Owing to the effect of interfacial chemistry on ORR performance, the formation of high‐valence Mn3+/4+ is beneficial in promoting the positive shift of the d‐band center, thereby optimizing the adsorption and desorption of ORR intermediates on the heterojunction surface and improving catalytic activity.