Facile synthesis of Ni(OH)2/graphene/bacterial cellulose paper for large areal mass, mechanically tough and flexible supercapacitor electrodes

A general approach toward flexible supercapacitor electrode based on metal hydroxide is developed, which offers ultrahigh areal capacitance without compromising their gravimetric capacitance and mechanical properties. As a prototype, bendable freestanding film is fabricated by coating graphene (RGO)wrapped flowery Ni(OH)(2) on bacterial cellulose (BC) with a rational combination of hydrothermal method and filtration technology. This as-assembled hierarchically structured flexible electrode is characterized by remarkable areal capacitance of 10.44 F cm(-2) (877.1 F g(-1)) at a large mass loading of 11.9 mg cm(-2), excellent cycling stability with 93.6% capacitance retention after 15,000 cycles, high flexibility including bending to arbitrary angles (even 180) and prominent tensile strength (48.8 MPa at wet state). Furthermore, it is hoped that the typical method can be applied for realizing other metal oxide/hydroxide flexible electrodes. The simple, high scalable, low-cost, and general strategy could open up new opportunities for flexible energy storage devices. (C) 2016 Elsevier B.V. All rights reserved.