Exploring Vanadium Disulfide (VS2) Nanosheets as High-Efficiency Supercapacitor Electrodes

Abstract

Transition metal dichalcogenides (TMDs) emerge as promising electrode materials for next-generation electrochemical energy-storage devices. In the present study, vanadium disulfide (VS2), an underexplored TMD, is investigated as an electrode material for supercapacitors. VS2 nanosheets are synthesized via a single-step hydrothermal method at 220 °C for 24 h. Multiple characterization techniques, including Fourier-transform infrared, Raman spectroscopy, scanning electron microscope–energy dispersive X-ray analysis, and transmission electron microscope, confirm the formation of phase-pure VS2 nanosheets with a hexagonal structure. The specific surface area, measured using Brunauer–Emmett–Teller analysis, is 12 m2 g−1. A specific capacitance of 106 F g−1 at a current density of 1 A g−1 is demonstrated using symmetric supercapacitors fabricated using these VS2 nanosheets. Using this device, an energy density of 34 Wh kg−1 at a power density of 800 W kg−1 is achieved. Moreover, the supercapacitor maintains 94% capacitance retention after 9000 charge–discharge cycles at 5 A g−1, highlighting the potential of VS2 nanosheets as efficient electrode materials for supercapacitor applications.