Probing the formation of graphene oxide and reduced graphene oxide from annealed graphite: a multifaceted approach

This research presents a simple, low-cost technique for synthesising graphene oxide (GO) and reduced graphene oxide (rGO) through the annealing of graphite at 650°C for times of 2, 4, and 6 hours, without using hazardous strong acids and oxidants typically used in traditional methods. X-ray diffraction (XRD), FT-IR, and UV-Vis spectroscopy were used to monitor how the structure changed. Annealing at 2 and 4 hours produced GO, as shown by the XRD peak at 2θ = 10.7°, the FT-IR band at ∼1020 cm-1 for the C-O, and the UV-Vis absorptions at ~268 and ~368 nm. Longer annealing (6 hours) produced rGO, which is shown by the loss of oxygen-related features, the decrease of the ∼300 nm UV-Vis shoulder, and the strong peak at ∼270 nm. The results show a time-dependent process (graphite → GO → rGO) with an intermediate interaction regime. This implies that altering the annealing duration can precisely control the oxidation state.