Supercapacitors based on patronite-reduced graphene oxide hybrids: experimental and theoretical insightsElectronic supplementary information (ESI) available. See DOI: 10.1039/c5ta03221k

Here we report the hydrothermal synthesis and detailed study on supercapacitor applications of a patronite hybrid, VS 4 /reduced graphene oxide, which showed an enhanced specific capacitance of ∼877 F g −1 at a current density of 0.5 A g −1 . In comparison to bare vanadium sulfide and reduced graphene oxide, the hybrid showed ∼6 times and ∼5 times higher value of specific capacitance, respectively. The obtained energy density (117 W h kg −1 ) and power density (20.65 kW kg −1 ) are comparable to those of other reported transition metal sulfides and their graphene hybrids. Theoretical calculations using density functional theory confirm an enhanced quantum capacitance of VS 4 /graphene composite systems, owing primarily to the shifting of the graphene Dirac cone relative to the band gap of VS 4 . The results infer that the hybrid has the potential to be used as a high performance supercapacitor electrode. Experimental and theoretical investigations of VS 4 /RGO hybrids towards their possible application as supercapacitors for energy storage.