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

Abstract

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.