Self-Supporting GaN Nanowires/Graphite Paper: Novel High-Performance Flexible Supercapacitor Electrodes

Flexible supercapacitors have attracted great interest as energy storage devices because of their promise in applications such as wearable and smart electronic devices. Herein, a novel flexible supercapacitor electrode based on gallium nitride nanowire (GaN NW)/graphite paper (GP) nanocomposites is reported. The outstanding electrical conductivities of the GaN NW (6.36 x 10(2) S m(-1)) and GP (7.5 x 10(4) S m(-1)) deliver a synergistically enhanced electrochemical performance that cannot be achieved by either of the components alone. The composite electrode exhibits excellent specific capacitance (237 mF cm(-2) at 0.1 mA cm(-2)) and outstanding cycling performance (98% capacitance retention after 10 000 cycles). The flexible symmetric supercapacitor also manifests high energy and power densities (0.30 mW h cm(-3) and 1000 mW cm(-3)). These findings demonstrate that the GaN/GP composite electrode has significant potential as a candidate for the flexible energy storage devices.