Cobalt-doped manganese(iii) oxide cathode materials with enhanced electrochemical performance for aqueous zinc-ion batteries

Abstract

Manganese oxides are recognized as promising cathode candidates for aqueous zinc-ion batteries (ZIBs). Nevertheless, the significant capacity decline attributed to manganese dissolution and the sluggish diffusion kinetics continue to serve as prominent obstacles, constraining their further advancement. To address these challenges, Co–Mn₂O₃ is prepared as a cathode material for ZIBs via a CoMn glycerate derivatization method. When assessed at 0.2 A g⁻¹, the ZIB employing Co–Mn₂O₃ exhibits a specific capacity of 289.7 mA h g⁻¹, and following 200 cycles, it retains 91.6% of its initial capacity. Ex situ characterization techniques offer evidence validating the Zn²⁺/H⁺ co-intercalation mechanism, confirm the suppressive impact of cobalt doping on manganese dissolution, and elucidate the irreversible structural alteration of Co–Mn₂O₃ throughout the charge and discharge processes. This research provides important understanding for future design and research of high-performance manganese-based cathodes for ZIBs.