Copper nanoparticles incorporated porous carbon nanofibers as a freestanding binder-free electrode for symmetric supercapacitor with enhanced electrochemical performance

A freestanding and binder free copper/porous carbon nanofibers (Cu/PCNFs) composite has been synthesized by a simple and cost effective electrospinning technique. The synthesized composite exhibits a unique morphology with high surface area of about 330.48 m2g-1 and high conductivity of 767.95 Sm-1. In a three electrodes system, the resultant Cu/PCNFs electrodes show a specific capacitance of 333.5 Fg-1 at a current density of 1 Ag-1 in 1 M of H2SO4 aqueous electrolyte. The assembled quasi-solid state symmetric supercapacitor (q-SSSC) exhibits a high specific capacitance value of 177.01 Fg-1 at a current density of 1.5 Ag-1 in PVA/H2SO4 polymer gel electrolyte with 95.8% capacitance retention up to 10 000 cycles. This q-SSSC can effectively deliver a high energy density of 24.53 Wh kg-1 at a power density of 1500 W kg-1. Thus, the synthesized Cu/PCNFs composites could be useful as an effective electrode material for next-generation high performance flexible supercapacitors.