Performance evaluation of Bi₂O₃@GO and Bi₂O₃@rGO composites electrode for supercapacitor application

Supercapacitors have been attracting a remarkable research interest due to their outstanding intrinsic properties, such as high electrical response, great durability, and a wide range of operating temperature and voltage. In this work, the synthesis and evaluation of the electrochemical performances of graphene oxide doped with Bismuth oxide (Bi₂O₃@GO) and reduced graphene oxide doped with Bismuth oxide (Bi₂O₃@rGO) without any binder material were carried out using a low concentration (1.0 M) of KOH electrolyte. The solvothermal method of nanomaterial synthesis was employed. The produced nanomaterial was studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), and electrochemical characterizations. An improved performance was recorded by the electrode made of Bi₂O₃@rGO, which achieved 560 Fg⁻¹ specific capacitance at 5 mVs⁻¹ scan rate; 28 Whkg⁻¹ and 17 kWkg⁻¹ energy and power densities, respectively. The electrode also retained 99% of its capacitance after 3000 galvanostatic charge–discharge (GCD) cycles.