Comprehensive design and fabrication of high capacitance electrode using self-supporting carbon derived from kapok fiber skeleton

Reducing the internal resistance of carbon electrodes without introducing adhesive during the constructed electrode process is of great significance. In this work, self-supporting carbon supercapacitor electrodes were constructed using kapok fiber and chitosan biomass. In the self-supporting system, the chitosan as a binder provided a stable structure and improved pseudocapacitance, while the kapok fiber as a skeleton provided smooth channels for ion transfer and storage. The obtained self-supporting carbon (C800K0.4) was in the form of aerogel with a suitable pore structure distribution (75.5% micropores). The unique structures of C800K0.4 resulted in a specific capacitance of 201.8 F/g (0.83 F/cm2, 5.45 F/cm3), and the capacitance retention rate was approximately 94.83% after 10,000 cycles. In addition, the assembled symmetric supercapacitor had a maximum energy density of 1000 W/kg. The self-supporting carbon supercapacitor electrode broke interface limitations in biomass-based carbon transport and improved the specific capacitance of the carbon supercapacitor.