Electro-deposition of CoNi2S4 flower-like nanosheets on 3D hierarchically porous nickel skeletons with high electrochemical capacitive performance

Abstract

Ternary cobalt nickel sulfide (CoNi₂S₄) flower-like nanosheets are directly grown on three dimensional (3D) hierarchically porous nickel skeletons by one-step electro-deposition. The resultant 3D porous Ni/CoNi₂S₄ composites could serve as binder-free integrated electrodes for supercapacitors, which exhibit higher capacitance than those of 3D porous Ni/Co₉S₈, 3D porous Ni/Ni₃S₂, Ni foam/CoNi₂S₄ and smooth Ni/CoNi₂S₄ electrodes. Furthermore, the 3D porous Ni/CoNi₂S₄ electrodes demonstrate better electrochemical reversibility and excellent rate capability. The super electrochemical capacitive behavior might be attributed to the highly interconnected conductive networks of 3D hierarchically porous Ni scaffold supported CoNi₂S₄ flower-like nanosheets with a large specific area and highly active sites.