Supercapacitors based on patronite-reduced graphene oxide hybrids: experimental and theoretical insights

Abstract

Here we report the hydrothermal synthesis and detailed study on supercapacitor applications of a patronite hybrid, VS<inf>4</inf>/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<inf>4</inf>/graphene composite systems, owing primarily to the shifting of the graphene Dirac cone relative to the band gap of VS<inf>4</inf>. The results infer that the hybrid has the potential to be used as a high performance supercapacitor electrode. � The Royal Society of Chemistry.