Hydrangea-Like VS4 Microspheres: A Novel Structure Material for High-Performance Electrochemical Capacitor Electrode

Novel hydrangea-like VS4 nanomaterials as high-performance electrode materials of supercapacitors were successfully synthesized by hydrothermal method using Na3VO4 · 12H2O2, citric acid and TAA (thioacetamide). The prepared samples were characterized by XRD, SEM and BET, CV (cyclic voltammetry) and GCD (galvanostatic charge and discharge). The results revealed that VS4 are hollow microspheres with a diameter of ~5 μm and made of nanosheets, the microspheres formed from diffusion growth of solid microspheres. These materials exhibited a tremendous specific capacitance of 533 F/g, at 0.1 A/g in the potential range of −0.9 to 0 V when used as supercapacitor electrodes in a solution of 1 M Na2SO3. The energy density is as high as 60 Wh/kg, which is much higher than those of many other symmetrical supercapacitors. In addition, the capacity retention of 80% was achieved even after 500 cycles, demonstrating the high performance of vanadium oxide nanomaterials used in supercapacitors.