Uniform Electric Fields-assisted MnO₂/rGO Electrode for High-Performance Zinc-Ion Batteries

Manganese-based oxides hold significant promise as commercially viable cathodes in aqueous zinc-ion batteries (ZIBs). However, their practical applications are currently hindered by several challenges, including poor conductivity, slow ion transport, and structural instability. In this study, we develop a high-performance V-MnO₂/rGO cathode via electrostatic self-assembly. The incorporation of Mn vacancies in MnO₂ results in the redistribution of localized charges, while the integration with rGO generates uniform internal electric fields that enhance both electron transfer and ion transport. Moreover, the formation of robust electrostatic interactions strengthens the interface contact between V-MnO₂ and rGO, thereby promoting enhanced structural stability. As a result, the V-MnO₂/rGO cathode exhibits excellent electrochemical performance, attaining a reversible capacity of 167.5 mAh g^-1 at 2 A g^-1, a maximum power density of 1628.0 W kg^-1, and 88.6% capacity retention after 1000 cycles at 1 A g^-1. Furthermore, the V-MnO₂/rGO-based flexible ZIB is capable of stably powering microelectronic devices, exhibiting high flexibility and electrochemical stability. This study provides valuable insights into the incorporation of Mn vacancies and electrostatic interactions in developing high-performance energy storage devices.