In-situ electrochemical induced artificial solid electrolyte interphase for MnO@C nanocomposite enabling long-lived aqueous zinc-ion batteries

Rechargeable aqueous zinc-ion batteries (AZIBs) have attracted widespread attention as a sustainable energy storage system owing to the safe aqueous electrolyte. Manganese-based materials are potential cathodes for AZIBs, whereas, the dissolution of manganese would result in the significantly decline of capacity and unsatisfied lives. Herein, an in-situ electrochemical induced artificial solid electrolyte interphase (SEI), (Zn(OH) 2 ) 3 (ZnSO 4 )(H 2 O) 5 nanoflakes, is discovered to generate and coat on the surface of MnO@C in the initial charging process which could prevent the direct contact between the electrolyte and electrode with the result of inhibiting the excessive dissolution of manganese oxides. Benefiting from the artificial SEI, MnO@C exhibits an extremely excellent cycle performance with 0.003% capacity decay per cycle over 10,000 cycles without Mn 2+ additive in electrolyte. Moreover, MnO@C is proved to demonstrate a (de)intercalation reaction mechanism after the electrochemical activation process in initial charging process. The strategy proposed in this study provides a new proposal to develop high stable manganes oxide cathodes for AZIBs.