Biomass-based functional materials for rechargeable Zn-ion batteries

Zn-ion batteries have recently generated great enthusiasm in the energy storage and conversion field due to the high theoretical specific capacitance and low redox potential. Although remarkable progress has been made in the exploration of performance, several challenges are faced in its development, such as Zn dendrites, instability of cathode materials, and low operating voltage. Biomass-based materials with appealing eco-friendliness, enriched surface chemistry, and diverse architecture could provide a potential candidate for developing highperformance Zn-ion batteries. In the review, the chemical structures, physical characteristics, and synthesis strategies of biomass-based materials are firstly introduced. Then, the structures and working principles of Zn-ion batteries are described. The key roles of biomass-derived functional materials in anode and cathode, electrolytes, as well as the underlying mechanisms are elucidated. In addition, the remaining challenges of biomass-based functional materials for rechargeable Zn-ion batteries and the underlying approaches to facilitate further development and research are presented and proposed.