Preliminary study of exfoliated graphite (EG) produced by electrochemical exfoliation and EG-TiO2 composite

Abstract

In this research, Exfoliated Graphite (EG) materials have been synthesized using the electrochemical exfoliation method. The starting materials are graphite sheets, before the exfoliation process, a simple pre-treatment was carried out, by immersing the graphite sheet in a mixture solution of sulfuric acid (H2SO4) and hydrogen peroxide (H2O2) with a ratio of 95:5 to widen the interlayer distance in graphite sheets for the optimum electrochemical exfoliation process. This study used ammonium sulfate solution (NH4)2SO4 as an electrolyte with a concentration 0.25 M. The obtained EG materials are then composited with TiO2 to increase the resulting energy density of the materials. The in-situ sol-gel method was used to synthesize the EG-TiO2 composite assisted by microwave irradiation. The resulting materials were characterized using X-ray diffraction (XRD), Fourier Transform infrared (FTIR), and LCR meter. Based on the XRD results, the EG-TiO2 composite showed an amorphous structure with an average crystallite size of 24.9 - 49.9 nm. It also shows that the XRD pattern of the EG-TiO2 composite has a lower peak intensity than the EG material. The FTIR result shows that the functional group of the rGO-TiO2 composite has a combination of Ti-O-Ti and Ti-O-C vibrations, which indicates the chemical interaction of TiO2 with EGs.