Novel effective strategy for high-performance biomass-based super-flexible hierarchically porous carbon fibrous film electrode for supercapacitors

Abstract Biomass-derived porous carbon electrode material is becoming a research focus recently for application in energy storage fields, however directly fabricating high-performance porous carbon fibrous film electrode based on biomasses still remains a great challenge. Herein, we adopted the hydrothermally-treated and manganese-acetate-soaked bamboo pulp to form paper by suction filtration and then directly carbonized it to prepare hierarchically porous carbon fibrous film. We found that KOH-Na2SO3-assisted hydrothermal treatment endows bamboo-pulp-derived carbon fibrous film with superior mechanical flexibility capable of being repeatedly folded and that manganese acetate post-soaking greatly improves the electrochemical performance. The targeted super-flexible carbon fibrous film possesses outstanding electrochemical performance with a specific capacitance of up to 331 F g−1 at a current density of 1 A g−1. The assembled all-solid-state symmetric supercapacitor shows a high energy density of 10.3 W h kg−1 at a power density of 250 W kg−1.