A New High‐Performance Porous Carbon‐Coated Mn₃O₄/Na₂CO₃ Cathode for Suppressing Mn²⁺Dissolution in Aqueous Zinc Ion Batteries

Abstract

Manganous‐manganic oxide (Mn3O4), akin to other manganese‐based oxides, faces several critical challenges such as substantial capacity fading and limited rate performance due to its inferior electrical conductivity, in addition to the inevitable dissociation of Mn 2+ . To address these issues, we introduce for the first time a novel carbon‐coated Mn3O4/Na2CO3 (Mn3O4/Na2CO3/C) composite material. Comprehensive characterizations indicate that Na2CO3 effectively curtails Mn 2+ dissolution, enhances carbon encapsulation throughout charging/discharging cycles, and exposes additional active sites on the Mn3O4/Na2CO3/C composite. Electrochemical assessments confirm that the Mn3O4/Na2CO3/C‐2 cathode exhibits exceptional electrochemical performance, outperforming other cathodes in the ZnSO4 system. Moreover, the Mn3O4/Na2CO3/C‐2 cathode delivers a high specific capacity of ~550 mAh g ‐1 at 0.1 A g ‐1 and maintains a significant capacity of ~230 mAh g ‐1 after 360 cycles at 1.0 A g ‐1 within the 2.0 M ZnSO4+0.2 M MnSO4 electrolyte system, demonstrating its potential as a high‐performance cathode material for aqueous zinc‐ion batteries.