High-Performance Flexible Asymmetric Supercapacitors Facilitated by N-doped Porous Vertical Graphene Nanomesh Arrays

The design of self-supporting electrode scaffold with large surface area, good flexibility, and high electrical conductivity is of great significance to the development of high performance flexible supercapacitors. Herein, we report the fabrication of N-doped porous vertical graphene nanomesh arrays (NVGMs) on flexible carbon cloth (CC) substrate (CC@NVGMs) via a facile self-sacrificing template method. The NVGMs provide large surface area, more growth sites of active materials, good electrical conductivity and short diffusion paths, leading to greatly enhanced performance. After decorating MnO2 nanosheets and polypyrrole films on the NVGMs, the hierarchical nanohybrid electrodes show notable improvement of areal capacitances, greatly decrease of equivalent series resistance, significantly enhancement of rate performance, compare to those of the active materials on bare CC. Furthermore, the flexible asymmetric supercapacitor is assembled by these two nanohybrid electrodes has an energy density of up to 1.92 mWh cm(-3).