Synthesis of honeycomb-like NiS2/NiO nano-multiple materials for high performance supercapacitors.

Three dimensional (3D) honeycomb-like NiS 2 /NiO nano-multiple materials were successfully prepared by fabricating cribrate NiS 2 on the surface of NiO nanosheets through simple hydrothermal process on nickel foam. The morphology and phase structure of the NiS 2 /NiO are characterized by scanning electron microscopy equipped with energy dispersive X-ray spectrometer, transmission electron microscope, X-ray diffractometer and the electrochemical properties are tested by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy. The NiS 2 /NiO electrode owns lower electrochemical impedance compared with bare NiO substrate and exhibits exceptional capacitance performance with a high specific capacitance of 2251 F g −1 delivered at current density of 1 A g −1 , while 1192 F g −1 retained at 20 A g −1 . What's more, after 2000 cycles, the specific capacitance remains 1275 F g −1 (at 5 A g −1 ) with a capacitance retention of 78%. Therefore, the NiS 2 /NiO electrode shows remarkable electrochemical performance and has a promising future for electrochemical supercapacitors. [ABSTRACT FROM AUTHOR]