Multiple perspectives of advanced design strategies and mechanism insights on enhancing the performance of zinc-ion supercapacitors

Zinc-ion supercapacitors (ZSCs), emerging as advanced electrochemical energy storage devices, boast of high safety, power density and energy density, as well as eco-friendliness. However, there are three key factors currently impeding the development of ZSCs, including capacity decay of unstable cathodes, hydrogen evolution in the electrolyte, and dendrite formation on the zinc anode surface. To effectively tackle these challenges, the design of ZSCs should be approached comprehensively, considering various aspects. This work delves into the fundamental principles, advantages, and prospective applications of ZSCs. Detailed strategies for enhancing ZSC performance is summarized and the underlying mechanisms is elucidated, focusing on boosting cathode capacity, inhibiting dendrite growth on the anode, and regulating the ion–solvent structure in the electrolyte. Furthermore, this work analyzes future research directions for ZSCs, aiming to expand the voltage window, enhance energy density, extend cycle life, explore various application scenarios, and more effectively address the evolving requirements of future energy storage. The comprehensive optimization of the ZSC design shows great potential for unleashing their capabilities as a high-performance energy storage technology, playing a crucial role in the domain of sustainable energy.