Interwoven MnO/Co-derived N-doped carbon nanotube composites as highly efficient and durable bifunctional oxygen catalysts for zinc–air batteries

Abstract

Rechargeable zinc–air batteries (ZABs) have emerged as a compelling candidate for advanced electrochemical energy storage and conversion systems, owing to their exceptional theoretical energy density, cost-effectiveness, and environmental compatibility. Despite these advantages, their practical utility is restrained by the intrinsically sluggish kinetics of both the oxygen reduction (ORR) and oxygen evolution (OER) reactions. Herein, we present a novel coordination-assisted ball-milling approach to fabricate MnO/Co-N-CNT composites featuring a unique interwoven carbon nanotube architecture. This rationally designed microstructure not only facilitates more efficient ion diffusion and electron transport, but also exploits the synergistic interaction between cobalt and manganese species to substantially enhance ORR/OER activity and long-term stability. As a result, ZABs incorporating these advanced composites achieve an impressive peak power density of 247.6 mW cm⁻² and sustain stable cycling for over 115 hours. These findings offer fresh insights into strategic material design and hold significant potential for guiding the future development of high-performance electrochemical energy devices.