Boosting the Pseudocapacitive Behavior of Ga2(WO6)3 Through rGO Hybridization for Efficient Supercapacitors

In this work, we have synthesized gallium tungstate (Ga₂(WO₆)₃) integrated with reduced graphene oxide (rGO) as an electrode material via an ultrasonication-assisted hydrothermal method and investigated for high-performance supercapacitor applications. The fabricated electrode materials were characterized by x-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), and x-ray photoelectron spectroscopy (XPS). The results demonstrate the successful formation of a GaW/rGO nanocomposite with high crystallinity, uniform dispersion, and enhanced surface area. Electrochemical studies in a three-electrode configuration revealed significantly improved specific capacitance of 838 F g⁻¹ at 1 A g⁻¹ for Ga₂(WO₆)₃/rGO, outperforming pristine Ga₂(WO₆)₃ (629 F g⁻¹). The composite also exhibited excellent rate capability and outstanding cyclic stability, with 91.2% retention over 10,000 cycles. When assembled as an asymmetric supercapacitor device using activated carbon (AC) as the negative electrode, the Ga₂(WO₆)₃/rGO//AC cell achieved specific capacitance of 375 F g⁻¹ at 1 A g⁻¹, retained 93.2% capacitance after 5000 cycles, and delivered maximum energy density of 29 Wh kg⁻¹ at power density of 310 W kg⁻¹. The device also demonstrated practical applicability by powering a light-emitting diode (LED). The superior electrochemical performance is attributed to the synergistic effect between pseudocapacitive Ga₂(WO₆)₃ and highly conductive rGO, offering a promising route toward next-generation energy storage devices.