Synthesis and electrochemical analysis of a hierarchical Bi₂WO₆/rGO nanocomposite for hybrid symmetric supercapacitor applications

Herein, a hierarchical composite of bismuth tungstate (Bi₂WO₆)/reduced graphene oxide (rGO) is synthesized via a one-pot hydrothermal method. The crystal nature, morphology, functional groups, elemental and porosity structural of the electrode materials for supercapacitors were studied through XRD, FT-IR, Raman, SEM, HR-TEM, XPS and BET. The Cyclic voltammetry metrics of the Bi₂WO₆/rGO composite, pristine Bi₂WO₆, and graphene oxide (GO) electrodes are examined in a three-electrode system and shows a specific capacitance of about 439, 297, and 242 F g−1 respectively. The Bi₂WO₆/rGO composites attains an enhanced specific capacitance with improved cyclic stability of 97.6% and a columbic efficiency of 98% even after 2000 charge/discharge cycles. According to the Dunn analysing method, Bi₂WO₆/rGO composites exhibits hybrid nature with a 41% capacitive contribution and 59% diffusive contribution at a low scan rate. Further symmetric supercapacitor device has been demonstrating with two similar single electrodes of Bi₂WO₆/rGO with an energy density and power densities of 67 Wh Kg−1 and 850 W kg−1 respectively. These results highlight the potential of the Bi₂WO₆/rGO composite for use as an electrode material in supercapacitor applications.