Interface Engineering to Improve the Rate Performance and Stability of the Mn-Cathode Electrode for Aqueous Zinc-Ion Batteries

Aqueous zinc-ion batteries (ZIBs), especially the aqueous zinc-manganese batteries, have received considerable attention due to their low cost, safety, and environmental benignity. However, manganese oxide cathode materials usually suffer from unsatisfactory cycling stability. In this study, we report an interface engineering strategy to improve the performance of the Mn-based cathode electrode for ZIBs. Both the results of experiments and density functional theory confirmed that SnO2 can act as a "glue" to strengthen the interfacial interaction between the conductive graphene substrate and MnOOH, which plays a vital role during the charging/discharging process of manganese oxide. By this interface engineering strategy, the cycling stability of the in situ deposited Mn-based electrode was significantly improved, and a specific capacity of 271 mA h g-1 can be retained even after 1500 cycles. This study may provide a thought or establish a framework for the rational design of high-performance cathode materials for ZIBs via interface engineering.