Transforming biomass waste sauce-flavor liquor lees into porous carbons for high-performance aqueous zinc-ion hybrid capacitors

Abstract

Zinc-ion hybrid supercapacitors (ZHSCs) represent a promising advancement in energy storage technology, demonstrating superior energy and power densities. However, achieving further performance enhancement has been impeded by the challenge of developing capacitive cathode materials that effectively complement high-capacity zinc anodes. Here, sauce-flavor liquor lees, a form of biomass waste, are utilized as the precursor for synthesizing porous carbon materials (SFPC-A13) with an ultra-high specific surface area of 3051 m² g⁻¹. The results demonstrate that SFPC-A13 not only exhibits remarkable specific capacitance (354 F g⁻¹ at 0.5 A g⁻¹) when employed as a supercapacitor electrode but also delivers exceptional performance in carbon-based ZHSCs. The fabricated ZHSCs achieve a high specific capacity of 221.1 mA h g⁻¹ at 0.5 A g⁻¹ and an energy density of 160.9 W h kg⁻¹ at a power density of 949.7 W kg⁻¹. Notably, these ZHSCs maintain 100% capacity retention after 175 000 cycles at 10 A g⁻¹. This outstanding performance highlights the high compatibility and synergistic effect between sauce-flavor liquor lees-derived carbon materials and zinc anodes, providing a substantial contribution to the field of ZHSCs. Additionally, this approach offers a novel pathway for the high-value utilization of biomass waste, such as sauce-flavor liquor lees, in sustainable energy storage solutions.