Flexible and cross-linked N-doped carbon nanofiber network for high performance freestanding supercapacitor electrode

Flexible, cross-linked N-doped carbon nanofiber network (CLCF) is successfully prepared via electrospinning and carbonization process. CLCF shows a specific capacitance of 175 F/g at the current density of 50 A/g with an excellent rate capability of 78.5% of its initial capacitance from 0.5 A/g to 50 A/g under the mass loading of 1.2 mg/cm. Supercapacitor device based on CLCF exhibits high energy density of 5.9W h/kg with a power density of 1200 W/kg, as well as excellent cycling stability which achieves 106% capacitance retention after 20,000 charge-discharge cycles. Solid-state supercapacitor device displays outstanding mechanical flexibility and no obvious capacitance loss can be observed even when the device was bended to 180. Moreover, as scaffold for supporting PANi, capacitance retention of CLCF/PANi can reach 72% with the current density range from 0.5 to 50 A/g. All the results suggest that CLCF has great potential for application not only as supercapacitor electrode but also as scaffold for supporting capacitive materials. (C) 2015 Elsevier Ltd. All rights reserved.