Coal derived porous carbon fibers with tunable internal channels for flexible electrodes and organic matter absorption

Abstract

Coal-derived porous carbon fibers (CPCFs) were prepared by single-nozzle electrospinning the aqueous solution of acid treated coal and polyvinyl alcohol followed by thermal treatment in an inert atmosphere. The production yield of CPCFs was about 92% from coal. The structural, textural, and surface properties of CPCFs were investigated by means of spectroscopy, microscopy, and Brunauer–Emmett–Teller (BET) techniques. The results showed that the flexible CPCFs had an abundant pore structure and large specific surface area. The electrochemical performance of supercapacitor electrodes with these fiber mats was studied. The binder free electrodes showed a capacitance of 170 F g⁻¹ at a current density of 1 A g⁻¹ in 6 M aqueous KOH electrolyte. The electrodes also showed stable cycling performance without any decrease in the specific capacitance after 20 000 charge/discharge cycles at a current density of 2 A g⁻¹. Besides, the CPCFs were superhydrophobic and showed outstanding performance in oil-absorption and good circulation for the removal of dyes from water. These outstanding properties potentially make the flexible CPCFs a promising candidate for energy storage and environmental protection.