A High-Performance Silver-Doped Manganese Oxide Nanowire Cathode Based on Combination Displacement/Intercalation Reaction and Deposition-Dissolution Mechanism

Rechargeable aqueous zinc-ion batteries (ZIBs) have attracted increasing interest in large-scale energy storage systems due to their low cost, high safety, and high volumetric energy density. Manganese-based materials are one of most promising aqueous zinc-ion battery cathode materials but suffer from their low electrical conductivity, poor cycling stability and controversial energy storage mechanism. In this study, Ag0.8Mn8O16 nanowire, a kind of manganese-based cathode material was successfully prepared by using a hydrothermal method. Series results indicate that the discharging/charging process of Ag0.8Mn8O16 cathode involves the combination displacement/intercalation (CDI) reaction mechanism and deposition-dissolution mechanism. The CDI mechanism enables the generation of metallic silver during the discharge process, which greatly enhances the electronic conductivity of the material. Owing to the typical CDI mechanism and deposition-dissolution mechanism, the Ag0.8Mn8O16 shows an interesting capacity rise at low current density and can deliver a maximum capacity value of 508.1 mAh g-1 at 0.1 A g-1 with good rate capability (193.0 mAh g-1 at high current density of 4 A g-1) and acceptable cyclability (198 mAh g-1 after 1000 cycles at 2 A g-1). Our results provide an alternative strategy for boosting the electrochemical performance of manganese oxide-based ZIB cathode material