Recent advances in functional materials and devices for Zn-Ion hybrid supercapacitors

Zinc-ion hybrid supercapacitors (ZHSCs) are attracting significant attention due to their high energies/power densities, safety, and low cost. In this review, recent advances in the development of ZHSCs are summarized. Particular emphasis is placed on state-of-the-art cathodes (including carbon, metal oxides, MXenes, and redox-active polymers), anodes (including Zn-based composites and Zn-free materials) and electrolytes for ZHSCs. Furthermore, the latest research on functional ZHSC devices with miniaturized ZHSCs, fiber-shaped ZHSCs, self-chargeable ZHSCs and self-healing devices is reported. Finally, further developments with ZHSCs are envisaged for future research in this thriving field. This research is emphasized particularly on cathodes (such as carbon, metal oxides, MXenes, and redox-active polymers), anodes (such as Zn-based composite materials and Zn-free materials), electrolytes (organic/ionic liquid electrolytes, WiSs, redox electrolytes, polymer or solid electrolytes) as well as the design of a novel device for ZHSCs.