Preparation of polyaniline coated MnV2O6 as cathode material for Advanced Zinc Ion Batteries

Abstract

Aqueous zinc-ion batteries (ZIBs) have been recognized as new energy storage systems considering their high safety, low cost, and remarkable rate performance. Nevertheless, most ZIB cathodes exhibit large electrochemical polarization, which is often detrimental and hampers the stable cycling of batteries. Herein, we adopted a composite strategy by coating a high-molecular-weight organic layer to modulate the polarization in the MnV2O6 cathode. The synergistic effect between MnV2O6 and high-molecular-weight polyaniline, combined with the improved electronic conductivity, contributed to the accelerated zinc storage kinetics and the resulted narrow electrochemical polarization. In addition, the electrochemical performance of the aqueous zinc-ion battery is effectively improved. The pseudocapacitive composite cathode MnV2O6@PANI exhibits an average discharge capacity of 258.8 mA h g-1 at 100 mA g-1 and shows a good rate performance up to 1 A g-1, which is almost twice that of unmodified MnV2O6.