Higher oxidation level in graphene oxide

In present work, the powdered graphene oxide is produced by Modified Hummer's Method and followed by three characterization techniques X-ray diffraction (XRD), Raman Spectroscopy and UV-vis Spectroscopy. A intense 2 theta peak at 12 degrees in X-ray diffraction of graphene oxide is observed which corresponds to plane (001) of Graphene oxide. Raman Spectroscopy study reveals two peaks, raised at 1357 cm(-1)& 1593 cm(-1) which are designated as D & G peaks, respectively. UV-vis spectroscopy analysis shows that the absorption of photon by GO exhibits a single intense peak at 223 nm. The band gap found to be 3.89 eV using UV-vis spectroscopy. This is one of the maximum band gap ever reported. We found an ambiguity in the Oxygen to Carbon ratio of fully Oxidized GO due to difference in energy band gap value reported different in Huang et al. and Lundie et al. papers, as the energy band gap of GO depends upon the Oxygen to Carbon ratio. With assumption that at higher 0/C ratio band gap varies linearly and fully oxidized GO has 1:1 Oxygen to Carbon ratio, in accordance a hypothetical graph plotted including the reported value of these two results and present value. The extrapolated graph reveals the Oxygen to Carbon ratio comes out to be 62.38% in present work. (C) 2017 Elsevier GmbH. All rights reserved.