Facile synthesis of SnO2/graphene and Bi–SnO2/graphene-based nanocomposites as electrode materials for energy storage devices

Graphene-based nanocomposites are widely investigated as cathode materials for energy storage device. Herein, tin oxide-modified graphene (SnO2/G) and bismuth-doped SnO2/G (Bi–SnO2/G) nanocomposites with nanorod-like morphology were synthesized by the combination of electrochemical and wet chemical methods. The as-prepared nanocomposites were characterized using Raman spectroscopy, X-ray diffraction, fourier-Transform spectroscopy, and scanning electronic microscopy. Further, electrochemical impedance spectroscopy (EIS), galvanostatic charge-discharge (GCD) curves, and cyclic voltammetry (CV) were utilized to assess the ultra-capacitor properties of SnO2/G and Bi–SnO2/G nanocomposites.The electrochemical performance of SnO2/G and Bi–SnO2/G nanocomposites demonstrated exceptional specific capacitance of 487 F/g and 174 F/g, respectively, at 5 mV/s compared to as-prepared pristine graphene (108 F/g) and SnO2 nanoparticles (117 F/g). While, the GCD study confirmed the cyclic stability of these electrodes. Overall, the SnO2/G and Bi–SnO2/G nanocomposites have shown good electrochemical properties in all assays.