Advances in the regulation of kinetics of cathodic H+/Zn2+ interfacial transport in aqueous Zn/MnO2 electrochemistry

Rechargeable aqueous Zn-MnO2 energy storage systems have attracted extensive attention owing to their high theoretical capacity and non-flammable mild aqueous electrolytes. Nevertheless, the complicated reaction mechanism of a MnO2-based cathode severely restricts its further development. Therefore, it is crucial to clarify the kinetics of H+/Zn2+ interfacial transport in the MnO2 cathode for realizing controllable regulation of interfacial ion transport and then realizing high capacity and long lifespan. Recently, based on different reaction mechanisms, various strategies have been employed to improve the performance of aqueous Zn/MnO2 cells, such as surface modifications and structural engineering. Herein, we systematically summarize the recent advances in the modulation of interfacial H+/Zn2+ transport and related redox kinetics to effectively improve the electrochemical responses. Furthermore, the challenges of designing novel MnO2 cathodes have also been prospected in detail to provide possible guidelines for the development of Zn/MnO2 batteries.