Fabrication of the Oxygen Vacancy Amorphous MnO₂/Carbon Nanotube as Cathode for Advanced Aqueous Zinc‐Ion Batteries

Abstract

The serious limitations of MnO 2 are poor electrical conductivity and low utilization rate of electrochemical active area. These problems have seriously limited the application of MnO 2 aqueous zinc‐ion batteries (AZIBs). Herein, preparing MnO 2 uniformly loaded on carbon nanotubes with good electrical conductivity can greatly improve the poor electrical conductivity of MnO 2 . Moreover, by introducing oxygen vacancy, the surface capacitance, the reaction kinetics, and the electrochemical performance of MnO 2 is increased. The specific capacity of the V o ‐MnO 2 /CNT material is 314 mAh g −1 , at 0.2 A g −1 , and capacity retention of 81% is achieved after 1000 cycles. In particular, the prepared device presents a distinct energy density of 416.2 Wh kg −1 . As a result, the capacity as well as the cycle stability is effectively improved compared with the original MnO 2 .