Nanoarchitectonics with Expired Carbon Fiber Reinforced Polymer-Derived Carbon Layer@Carbon Fiber Coaxial Electrodes for Superior Supercapacitor Performance

Abstract

Inspired by the double demands of both collection/storage from new energy devices and storage/supply for consumption tools, energy storage attracts much attention, and electrodes play a crucial role. In our work, by using an expired carbon fiber reinforced polymer (CFRP) as the raw material, when the epoxy resin component is removed through pretreatment at 350 °C and retained epoxy resin on the surface of carbon fibers (CFs) is carbonized/activated at 650 °C, a coaxial structure of carbon layer@carbon fiber (C@CF) is acquired (specific area: 786 m² g^–1). This C@CF can be directly used as a supercapacitor electrode, which exhibits good electrochemical performance: a specific capacitance of 202 F g^–1 at 1 A g^–1 for its electrode (vs 11.1 F g^–1 for bare CF), while an energy density of 9.75 Wh kg^–1 and a specific capacitance retention of 93.27% after 10,000 cycles for its symmetric supercapacitor (SSC).