A high-performance silver-doped manganese oxide nanowire cathode based on combination displacement/intercalation reaction and deposition-dissolution mechanism

Abstract

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 while their practical applications in ZIBs are limited by their low electrical conductivity, poor cycling stability and controversial energy storage mechanism. In this work, Ag0.8Mn8O16, a kind of manganese-based cathode material with combination displacement/intercalation reaction was prepared by using a hydrothermal method. Due to combination displacement/intercalation reaction mechanism, the generation of metallic silver during the discharge process greatly enhances the electronic conductivity of the material and thus the Ag0.8Mn8O16 exhibits excellent rate performance and a reversible capacity of 198 mA h g−1 at 2 A g−1 after 1000 cycles. In addition, Ag0.8Mn8O16 shows an interesting capacity rise at low current density and through a series of comparative experiments, the existence of deposition dissolution mechanism in Zn/Ag0.8Mn8O16 battery was confirmed to be a critical factor of capacity increase.