Microwave assisted green synthesis of high capacitive TiO₂ doped rGO nanosheets for supercapacitor applications

The present study deals with synthesizing rGO nanosheets and TiO₂ nanoparticles by a green method using aloe vera and gram seeds, respectively, while a simple microwave-assisted approach has been used to prepare the TiO₂/rGO nanosheets composite. The as-prepared materials were investigated via different analytical techniques such as SEM, TEM, X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy and Raman spectroscopy. The TiO₂/rGO-NS composite showed a sheet-like nature and was deposited on a carbon cloth substrate using Nafion binder and used as the working electrode (cathode). The electrochemical properties of the as-prepared materials were studied using cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The TiO₂/rGO-NS composite fabricated on the carbon cloth substrate shows a relatively higher specific capacitance with lower charge transfer resistance. The TiO₂/rGO-NS composite coated carbon cloth cathode shows a maximum specific capacitance (599.9 Fg⁻¹) and energy density (83.31 Whkg⁻¹) at a current density of 1 Ag⁻¹.