Spherical PDA@MnO2 cathode for rechargeable aqueous zinc ion batteries

The PDA@MnO2 with unique structure was prepared by reacting KMnO4 with spherical PDA, and used as the cathode material of aqueous zinc ion batteries. Electrochemical test results show that, the spherical PDA@MnO2 had an initial discharge capacity of 378.4 mAh g−1 at a current density of 0.2 A g−1, indicating the superior performance compared to that of irregular PDA@MnO2. The spherical structure is beneficial to improve the electrochemical performance of the diffusion control process and achieve the purpose of improving the utilization rate and mass specific capacity of irregular PDA@MnO2. This excellent performance and novel structure demonstrate that spherical PDA@MnO2 can find a wide range of applications in energy storage.