▎ 摘　　要

Herein, we report multidimensional hybrid architectures wherein CoS2 nanoparticles are encapsulated in steam-activated reduced graphene oxide/carbon nanotubes (CoSx@srGO/CNT) for rechargeable Zn-air batteries. CoSx nanoparticles work as catalysts to grow CNT branches onto the srGO, and the CoSx@srGO/CNT act as bifunctional electrocatalyst for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER). The bifunctional ORR and OER activities of the CoSx@srGO/CNT are substantially greater than those of CoS2, srGO, and CoSx@srGO as confirmed by onset potentials, Tafel and K-L plots, and mass activities. Zn-air batteries with CoSx@srGO/CNT catalyst achieved a specific capacity of 583 mAhGreek ano teleiagzn = 1 and maximum power density of 66.45 mWGreek ano teleiacm = 2, which are greater than Pt/C and IrO2 mixed catalyst, along with a long-term cyclability of over 100 cycles. The outstanding performance of CoSx@srGO/CNT is attributed to the abundant exposed active sites of CoSx on a unique 3D multidimensional graphene/CNT hybrid architecture and the rapid mass/charge transport for the enhanced bifunctional activities. (c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.