A foldable, extra lightweight, flexible electrode: Chopped carbon fiber paper for growth of three-dimensional copper(II) hydroxide nanorod arrays

Flexible all-solid-state supercapacitors (FASSCs) have attracted much attention as power supplies for portable and wearable electronic products. Herein, we report the fabrication of a foldable, extra lightweight, flexible chopped carbon fiber paper (CFP) with a porous network structure prepared via wet-mold papermaking that can serve as a conductive substrate. The conductivity and pseudocapacitance of the electrode were improved by controlling the growth of 3D Cu(OH)(2) nanorod arrays on CFP substrate. The Cu (OH)(2)@CFP electrode has a high specific capacitance of 421.8 mF cm(-2) at a current density of 0.5 mA cm(-2) with capacitance retention of 82.98% at a current density of 10 mA cm(-2) after 5000 charge-discharge cycles. The FASSC manifested not only a large capacitance of 196.1 mF cm(-2) at 2 mA cm(-2), as well as energy and power densities of 6.97 x 10(-2) mWh cm(-2) and 1.6 mW cm(-2), respectively, but also excellent stability of 80.3% over 5000 cycles at 5 mA cm(-2). In addition, we confirmed that the FASSC has a large bending angle and can be twisted into various shapes, thereby indicating its applicability in portable and wearable electronic devices. (C) 2021 Elsevier B.V. All rights reserved.