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

The serious limitations of MnO2 are poor electrical conductivity and low utilization rate of electrochemical active area. These problems have seriously limited the application of MnO2 aqueous zinc-ion batteries (AZIBs). Herein, preparing MnO2 uniformly loaded on carbon nanotubes with good electrical conductivity can greatly improve the poor electrical conductivity of MnO2. Moreover, by introducing oxygen vacancy, the surface capacitance, the reaction kinetics, and the electrochemical performance of MnO2 is increased. The specific capacity of the V-o-MnO2/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 MnO2.

Automated summary

By uniformly loading MnO2 on carbon nanotubes and introducing oxygen vacancy, the electrical conductivity and electrochemical performance of MnO2 are significantly improved. The V-o-MnO2/CNT material shows a specific capacity of 314 mAh g(-1) and retains 81% capacity after 1000 cycles, with a distinct energy density of 416.2 Wh kg(-1), effectively enhancing the capacity and cycle stability as compared to the original MnO2.