Tailoring Oxygen Reduction Reaction Kinetics on Perovskite Oxides via Oxygen Vacancies for Low‐Temperature and Knittable Zinc–Air Batteries

• Published in: Advanced materials (Weinheim) 2023-09, Vol.35 (36), p.e2303109-n/a
• Main Authors: Huang, Hongjiao, Huang, Aoming, Liu, Di, Han, Wentao, Kuo, Chun‐Han, Chen, Han‐Yi, Li, Linlin, Pan, Hui, Peng, Shengjie
• Format: Article
• Language: English
• Subjects: Catalysts; Catalytic activity; Chemical reduction; Electrical resistivity; Electrocatalysts; Energy conversion; Energy storage; Graphene; Low temperature; Mass transfer; Materials science; Metal air batteries; Nanofibers; Oxide coatings; oxides; oxygen reduction reaction; Oxygen reduction reactions; Perovskites; Reaction kinetics; Synergistic effect; vacancies; Zinc-oxygen batteries; zinc–air batteries
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.202303109

High kinetics oxygen reduction reaction (ORR) electrocatalysts under low temperature are critical and highly desired for temperature‐tolerant energy conversion and storage devices, but remain insufficiently investigated. Herein, oxygen vacancy‐rich porous perovskite oxide (CaMnO3) nanofibers coated with reduced graphene oxide coating (V‐CMO/rGO) are developed as the air electrode catalyst for low‐temperature and knittable Zn–air batteries. V‐CMO/rGO exhibits top‐level ORR activity among perovskite oxides and shows impressive kinetics under low temperature. Experimental and theoretical calculation results reveal that the synergistic effect between metal atoms and oxygen vacancies, as well as the accelerated kinetics and enhanced electric conductivity and mass transfer over the rGO coated nanofiber 3D network contribute to the enhanced catalytic activity. The desorption of ORR intermediate is promoted by the regulated electron filling. The V‐CMO/rGO drives knittable and flexible Zn–air batteries under a low temperature of −40 °C with high peak power density of 56 mW cm−2 and long cycle life of over 80 h. This study provides insight of kinetically active catalyst and facilitates the ZABs application in harsh environment. The oxygen reduction reaction kinetics of a perovskite oxide is significantly promoted by a facile metal–vacancy strategy. The newly developed vacancy‐rich porous perovskite nanofibers exhibit comparable activities to the commercial Pt/C and even surpass it under low temperature. The developed catalyst can drive knittable fibrous‐type and sandwich‐type zinc–air batteries under low temperature of −40 °C with impressive performance.