Crystal plane induced in-situ electrochemical activation of manganese-based cathode enable long-term aqueous zinc-ion batteries

Abstract

Rapid capacity decay and sluggish reaction kinetics are major barriers hindering the applications of manganese-based cathode materials for aqueous zinc-ion batteries. Herein, the effects of crystal plane on the in-situ transformation behavior and electrochemical performance of manganese-based cathode is discussed. A comprehensive discussion manifests that the exposed (100) crystal plane is beneficial to the phase transformation from tunnel-structured MnO₂ to layer-structured ZnMn₃O₇·3H₂O, which plays a critical role for the high reactivity, high capacity, fast diffusion kinetics and long cycling stability. Additionally, a two-stage zinc storage mechanism can be demonstrated, involving continuous activation reaction and phase transition reaction. As expected, it exhibits a high capacity of 275 mAh g⁻¹ at 100 mA g⁻¹, a superior durability over 1000 cycles and good rate capability. This study may open new windows toward developing advanced cathodes for ZIBs, and facilitate the applications of ZIBs in large-scale energy storage system.