Polypyrrole-assisted surface-oxidized carbon cloth for high-performance flexible solid-state supercapacitors

As an outstanding kind of energy storage device, flexible solid-state supercapacitors have gained great popularity in the fields of portable and wearable electronics. The improvement of high-performance flexible electrodes for practical applications is urgently demanded. In this work, polypyrrole (PPy) nanoparticles anchored on the surface of carbon cloth (CC) are utilized to assist the surface oxidation of CC, which provides an abundance of heteroatoms to boost the electrochemical performance. The as-prepared material exhibits a high mass specific capacitance of 485 F g −1 at a current density of 0.5 A g −1 and an outstanding areal specific capacitance of 1454 mF cm −2 at a current density of 1.5 mA cm −2 . It nearly maintains the initial capacitance after 8000 cycles at a high scan rate of 200 mV s −1 and at a large current density of 10 A g −1 . Moreover, the flexible solid-state supercapacitor based on PPy-assisted surface-oxidized carbon cloth retains an eminent energy density of 35.47 Wh kg −1 (106.41 μWh cm −2 ) at a large power density of 250 W kg −1 (0.75 mW cm −2 ) and exhibits a capacitance retention of 102.6 % after 1000 bending cycles, demonstrating excellent cycling stability and flexibility. Therefore, this work will supply new insights for the design of flexible electrode materials for high-performance energy storage devices.