Synthesis of reduced graphene oxide/tungsten trioxide nanocomposite electrode for high electrochemical performance

Abstract A facile and well-controllable reduced graphene oxide/tungsten trioxide (rGO/WO 3 ) nanocomposite electrode was successfully synthesized via an electrostatic assembly route at 350 rpm for 24 h. In this study, hexagonal-phase WO 3 (h-WO 3 ) nanofiber was well distributed on rGO sheets by applying optimal processing parameters. The as-synthesized rGO/WO 3 nanocomposite electrode was compared with pure h-WO 3 electrode. A maximum specific capacitance of 85.7 F g −1 at a current density of 0.7 A g −1 was obtained for the rGO/WO 3 nanocomposite electrode, which showed better electrochemical performance than the WO 3 electrode. The incorporation of WO 3 into rGO could prevent the restacking of rGO and provide favourable surface adsorption sites for intercalation/de-intercalation reactions. The impedance studies demonstrated that the rGO/WO 3 nanocomposite electrode exhibited lower resistance because of the superior conductivity of rGO that improved ion diffusion into the electrode. To evaluate the contribution of WO 3 to the rGO/WO 3 nanocomposite, the influence of mass loading of WO 3 on the capacitance was investigated.