Porous Hierarchical Structure Ni(OH)2 Nanosheet Array Electrode with Excellent Electrochemical Energy Storage Performance

In this paper, we report a hierarchical structure Ni(OH)2 nanosheet array electrode by a directed liquid-phase approach, which consists of amorphous Ni(OH)2 interface layer and crystalline ultra-thin porous Ni(OH)2 nanosheets top layer. The testing results present that the maximum discharge capacity of 404.8 mA h g−1 at lower rate of 1.4 A g−1 and the ultra-high capacity of 1714 F g−1 at super-high rate of 50 A g−1 without decay after 3000 cycles was obtained, respectively. This unique design provides excellent flexibility, long and stable cycle lifetimes, high energy and power densities simultaneously.