3D hierarchical SnO₂@Ni(OH)₂ core-shell nanowire arrays on carbon cloth for energy storage application

A judicious combination of conducting materials with selected transition metal hydroxides to form core-shell nanostructures has attracted great attention owing to the underlying synergistic effect for energy storage. In this work, we fabricate a novel 3D nanostructure consisting of Ni(OH)₂ ultrathin nanoflakes directly anchored on SnO₂ nanowire arrays by a facile solution-based method, which utilizes the higher conductance of SnO₂ nanowires as the supporting scaffold to deposit Ni(OH)₂ for supercapacitor electrodes. Cyclic voltammetry and galvanostatic charge-discharge methods have been conducted to understand the capacitive performance of the SnO₂/Ni(OH)₂ core-shell nanocomposites. A specific capacitance of as high as 1553 F g^-1 is achieved at 0.5 A g^-1 in 6 M KOH aqueous solution. At a large current density of 10 A g^-1, the electrode retains a high capacitance value of 934 F g^-1. The superior capacitive behavior suggests that the hierarchical SnO₂@Ni(OH)₂ hybrid nanostructure is a very promising electrode material for fabricating high-performance supercapacitors.