Boosting Zn storage performance by regulating N/O functionalities of the durian peels derived sandwich-like porous carbon

Porous carbon materials derived from biomass are widely used as cathodes in Zinc-ion hybrid supercapacitors (ZIHSs) due to their inherent properties. However, understanding the link between biomass structure, composition, and electrochemical performance remains challenging. This study synthesized sandwich-like porous carbon materials (DrHPC) from durian peels. DrHPC features a unique sandwich-like structure characterized by abundant micropores, high specific surface area, elevated oxygen content, and minimal nitrogen content. These characteristics facilitate Zn2+ transport, provide active sites, enhance adsorption capacity, and improve kinetics. The aqueous Zn//DrHPC ZIHSs show significant specific capacity (232 mA h g−1 at 0.1 A/g), excellent rate capability (106 mA h g−1 at 10 A/g), high energy density (164 Wh kg−1 at 33 W kg−1), and long cycle life (96 % capacitance retention after 12,000 cycles at 10 A/g). Mechanistic studies reveal Zn2+ adsorption primarily on CO/NOx functional groups, enhancing pseudocapacitance. This research provides insights for designing advanced biomass-derived carbon materials for improved ZIHSs.