Vanadium sulfide/reduced graphene oxide composite with enhanced supercapacitance performance

Porous metal sulfide/carbon hybrid materials are promising functional composites that are extensively used in high performance supercapacitors. Here, we report electrochemical supercapacitance performance of hierarchical porous vanadium sulfide (V₃S₄)/reduced graphene oxide (RGO) composite (V₃S₄/RGO) prepared by hydrothermal method. The as prepared materials were characterized in detail by powder X-ray diffraction, scanning and transmission electron microscopy, Raman scattering, Fourier transformed infrared and X-ray photoelectron spectroscopy and the coherent growth mechanism was proposed. Porous hierarchical structure of V₃S₄/RGO composite material offered easy access to the ionic and electronic charge transportation and showed better electrochemical performance compared to the individual components. Specific capacitance of V₃S₄/RGO was found to be 520 F/g at a current density of 1 A/g with outstanding cyclic stability retaining 99.6% capacitance after 2000 charge–discharge cycles at 10 A/g. Cyclic voltammetry showed reversibility in current response both in cathodic and anodic scan and specific capacitance was found to be 500 F/g at a scan rate of 5 mV/s. These results strongly suggest that V₃S₄/RGO composite materials with hierarchical porous structure would be an excellent electrode material for supercapacitor applications.