Rational design and prospects for advanced aqueous Zn–organic batteries enabled by multielectron redox reactions

Due to their environmental compatibility, customizable molecular structures, and abundant organic host resources, aqueous Zn–organic batteries (AZOBs) are essential in constructing next-generation energy storage devices. Nevertheless, the current limitations of AZOBs of suboptimal energy density, inadequate rate capability, capacity decay caused by single redox groups, poor conductivity, and high solubility of organic hosts highlight the need for advancement. Therefore, organic cathode materials with multiredox centers and stable skeletons are continuously being pursued in developing high-performance AZOBs. These multifunctional organic compounds can cooperatively trigger multielectron redox reactions with facilitated H⁺/Zn²⁺ costorage, thereby significantly boosting the battery performance of organic cathode hosts. Furthermore, an imperative aspect of this study involves investigating the structure–function relationship between molecular structures and redox reaction mechanisms within multifunctional organic electrodes, particularly in the context of Zn–organic full-battery systems. This review outlines the challenges and strategies to enhance the redox potential, active capacity, redox kinetics, and cyclability of multifunctional organic cathode materials, providing a valuable foundation for future advanced AZOBs.