Superior cycle stability carbon layer encapsulated polyaniline nanowire core-shell nanoarray free-standing electrode for high performance flexible solid-state supercapacitors

Abstract

Polyaniline (PANI) materials possess extremely high theoretical capacitance and easy strategies to modify free-standing electrode for high performance flexible solid-state supercapacitors (FSSCs). However, low cycle stability of PANI limits its application. So how to improve cycle stability of PANI materials becomes particularly important. Herein, carbon layer is introduced to encapsulate PANI nanoarray grown on functional carbon cloth (fCC-PANI array-C) through hydrothermal method to improve cycle stability of this free-standing electrode. When reaction time is extended to 2 h, the fCC-PANI array-C exhibits high areal capacitance of 1695 mF/cm2 at 0.5 mA/cm2 and maintains extremely excellent cycle stability about 102% of its original value after 10 000 cycles at 100 mV/s. Furthermore, fCC-PANI array-C is employed to assemble FSSCs. The as-prepared FSSCs also exhibit high areal capacitance (819.62 mF/cm2) and keep 89% cycle stability after 5000 cycles at 50 mA/cm2. More importantly, the FSSCs show superior mechanical properties and flexibility, and still maintains 98% of its original value when bent at 180° after 1000 cycles. Moreover, the FSSCs are further employed as energy-storage device to light up a red LED. Therefore, FSSCs based on fCC-PANI array-C exhibit possibility that can be applied as high property flexible energy-storage devices.