Evaluation of reduced graphene oxide/WO3/WS2 hybrids for high performance supercapacitor electrode

Reduced graphene oxide (rGO) is added to WO3 and WS2 to develop several hybrid electrode materials, including rGO/WO3, rGO/WS2, and rGO/WO3/WS2 by a simple and cost-effective hydrothermal method to enhance the electrochemical performance. The structural/ morphological analysis of synthesized rGO/WO3, rGO/WS2, and rGO/WO3/WS2 hybrids were extensively characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), X-ray photoelectron spectroscopy (XPS), Raman spectra, ther-mogravimetric analysis (TGA) and Brunauer-Emmett-Teller (BET) surface area. The extensive character-ization shows that WO3/WS2 nanoparticles were homogeneously dispersed throughout the surface of rGO. The rGO/WO3/WS2 exhibits higher specific capacitance of 750 F/g at 10 mV/s as compared to rGO/WS2 (481 F/g), rGO/WO3 (382 F/g), and rGO (154 F/g). The rGO/WO3/WS2 electrode was found to have Rct and Rf values of 1.3 ohm cm2 and 1.5 ohm cm2, respectively. These values were found to be much lower than that of rGO electrode (47.2 ohm cm2 and 36.4 ohm cm2), indicating that the rGO/WO3/WS2 has much less resistances, which may be one of the primary causes of the outstanding electrochemical properties of the rGO/WO3/WS2. The retention capacity of 95.33 % upto 10,000 cycles at 1 A/g shows that this rGO/WO3/WS2 hybrid electrode also exhibits good cycling stability. The rGO/WO3/WS2 composites' respective energy and power densities are observed to be 702 Wh/kg and 5912 W/kg. The rGO/WO3/WS2 hybrid has been shown to be a superior anode material in supercapacitors because of the synergistic interaction of WS2, rGO, and WO3. These advantages include a bigger contact surface area, a shorter ion diffusion path, great charge transfer, and, most importantly, rGO's improved specific capacitance. It reveals that the rGO/WO3/WS2 hybrids can be a promising electroactive material for supercapacitor applications.(c) 2023 Elsevier B.V. All rights reserved.