Modification of morphological, structural and optical properties of graphene oxide by alteration molarity of aqueous KMnO 4 solution

This work reports a nontraditional modified Hummer's method to synthesize graphene oxide (GO) nanosheets by adjusting the oxidation process via a different-molarity potassium permanganate (KMnO4) solution instead of utilizing its powder. The effect of KMnO4 concentrations on the structural and morphological properties of GO nanosheets was studied. Oxidant solutions of 0.5 M, 1 M and 1.5 M were experimented to control the properties of the GO layers. Then, the samples were characterized by X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), Raman and ultraviolet-visible (UV–Vis) spectroscopes. Finally, oxidant concentration was optimized at 1 M by which thinner, high-quality crystalline GO layers and wider bandgap energy (Eg ) were obtained. It is thus confirmed that such a modification in the oxidation is a pioneering process to improve the GO properties.