Hierarchically porous nickel oxide nanoflake arrays grown on carbon cloth by chemical bath deposition as superior flexible electrode for supercapacitors

Abstract

Hierarchical porous NiO nanoflake arrays on carbon cloth are fabricated by a simple chemical bath deposition (CBD) method. Free-standing NiO nanoflakes with thicknesses of ~10nm grow quasi-vertically to the carbon cloth forming an integrated flexible electrode. When evaluated as electrode materials for supercapacitors, such nanoflake array electrode exhibits electrochemical performances with high capacitance and desirable high-rate cycle life. The porous NiO nanoflake arrays on carbon cloth deliver a high specific capacitance of 660Fg−1 at 2Ag−1. In addition, the integrated flexible electrode exhibits excellent mechanical behavior and long-term cyclic stability (82% retention after 4000 cycles).