Facile synthesis of highly favorable graphene oxide: effect of oxidation degree on the structural, morphological, thermal and electrochemical properties

Abstract

An efficient and facile production of highly favorable graphene oxide (GO) via modified Hummers’ method at different oxidation degrees was successfully demonstrated. The formation of oxygen containing functional groups and their effects on GO structural properties were analyzed by UV–visible spectrophotometry (UV–vis), Fourier transform infrared spectroscopy (FTIR), x-ray diffraction (XRD) and Raman spectrophotometer. The presence of hydroxyl (-OH), carboxyl (-COOH), epoxy (C–O–C) and carbonyl (C[dbnd]O) groups in GO and their intermolecular interaction were analyzed by FTIR. XRD pattern of GO showed the dominant peak at 10.8° with interlayer spacing (0.82 nm) larger than pristine graphite (0.34 nm) owing to the addition of oxygen with functional groups. High-resolution transmission electron microscopy (HRTEM) analysis showed highly transparent layers of GO-9 with distinct flake like shape. The electrochemical property of GO was observed to increase with lower amount of oxygen containing functional groups. These synthesized GO with valuable properties have high potential to serve as a precursor for the production of various graphene-based materials application.