An electrochemical approach for bulk production of reduced graphene oxide from graphite oxide followed by thermal reduction

Abstract

A high-quality, bulk synthesis of graphene that is inexpensive, and environmentally safe is highly desired because of the broad range of applications. In comparison to the chemical vapor deposition (CVD) method, epitaxial growth on silicon carbide, etc., the electrochemical approach is thought to be the most straightforward and eco-friendly way for the cost-effective bulk production of graphene from graphite. Moreover, the thermal reduction method appears to be a particularly cost-effective way to eliminate oxygen-containing functional groups when compared to chemical reduction. The yield of graphene is also impacted by the choice of cathode low-cost, which is extremely important and played a critical role during the synthesis process. In this work, we demonstrate a green, eco-friendly, and cost-effective electrochemical method for the synthesis of reduced graphene oxide (RGO) followed by thermal reduction. To accomplish electrochemical exfoliation for the graphene synthesis, a constant DC power of 65[Formula: see text]W ([Formula: see text][Formula: see text]V and [Formula: see text][Formula: see text]amp) has been supplied within an electrolytic cell that contains 2[Formula: see text]M of sulphuric acid as an electrolytic solution. The aluminium has been utilized as a cathode in place of the platinum, carbon cathode, etc. Moreover, to prepare the electrolytic solution and for the sonication process, sterilized water has been used in place of DI (deionized water). Thereafter, previously oxidized graphite oxide has been thermally reduced at a temperature of [Formula: see text]C. The phase, crystallinity, and interatomic distance were investigated using X-Ray diffraction (XRD) analysis. X-Ray data show that the RGO crystal structure has been recovered following high-temperature annealing. The diffraction peak seems to be at [Formula: see text] with an interplaner distance of 3.48[Formula: see text]Å. The intensity of the defect, as measured by the [Formula: see text] ratio (intensity ratio), was analyzed using Raman spectra, and the result of that investigation was found to be 0.196. The findings of the Raman study unambiguously reveal that the severity of the defects is judged to be on the lower end of the spectrum. The surface texture, microstructure, and elemental analysis were performed using atomic force microscopy (AFM), Field emission scanning electron microscopy (FESEM), transmission electron microscope (TEM), and EDX analysis. Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA) were used to determine the number of oxygen-containing functional groups that existed in the RGO sample and their thermostability. The results of FTIR and TGA analysis clearly demonstrate that the reduction temperature has a major role in determining the proportion of oxygen that is present in the graphene. This study presents a large-scale, cost-effective, and eco-friendly graphene synthesis method for industrial applications.