Overall upgrading Zn-ion storage capability by engineering N/O co-doped hydrophilic hierarchical porous carbon

Abstract

The couple of supercapacitors' high power density and batteries' high energy density endows aqueous zinc-ion hybrid supercapacitors (ZIHSCs) a perspective candidate for next-generation energy storage devices. Biomass-derived hierarchical porous carbon with excellent wettability towards aqueous electrolyte is regarded as a promising cathode for ZIHSCs applications. Herein, a N/O co-doped hydrophilic carbon with hierarchical porous architecture is conversed from protein enriched recycled badminton feathers via a facile and scalable strategy. The resultant carbon presents hierarchical porous architecture with high surface area and mesopore-governed pore size distribution, rich dual-doping of N/O heteroatoms and good water wetting behavior. The all-round teamwork of these unique properties provides numerous interfacial active sites plus extra reversible redox reaction for high energy density, and speedy kinetics for high power density. Incredibly, as-assembled ZIHSC device displays an ultrahigh capacity of 225.3 mAh g−1 at 0.1 A g−1 with an appreciable capacity retention of 73.8 mAh g−1 even at a 1000-fold amplified current density, thereby delivering admirable energy and power densities of 201.4 Wh kg−1 and 83.6 kW kg−1. Most satisfyingly, an ultralong cycling life with no loss in capacity is achieved after 40,000 cycles even at 50 A g−1. Therefore, by taking advantage of its intrinsic component, the conversion of biomass waste to high performance carbon-based cathode material holds a broad prospect and practical significance.