Effect of characterization probes on the properties of graphene oxide and reduced graphene oxide

Graphene Oxide (GO) has tremendous application potential as a functional material. However, we found GO to be extremely sensitive toward external energy in the form of heat, light, X-rays, etc. It is because the Oxygen Functional Groups (epoxide, carbonyl, carboxyl, hydroxyl, etc.) attached to the underlying monomolecular layer of carbon in GO are prone to reduction through externally supplied energy leading to the formation of reduced Graphene Oxide (rGO). Eventually, GO lacks preserving its original chemical composition, physical and chemical properties while interacting with the measurement probes. In addition, GO also undergoes a gradual reduction over a period in an ambient environment. This obvious behavior of GO compelled us to re-examine the related literature. In this report, we studied the detailed effects of various characterization tools, possible ways to minimize the side-effects while measurement, and an alternative way to use GO for its various uses. This involved the review of not only the different important parameters of the characterizing probes but also its synthesis protocols and the environment of its storing desiccator. In this direction, we report a careful set of experiments using X-ray Diffraction, X-ray Photoemission Spectroscopy, Raman Spectroscopy, UV-Visible Spectroscopy, Photoluminescence Spectroscopy, Transmission Electron Microscopy and Atomic Force Microscopy. This elucidates the precautions needed while establishing the best practices in GO synthesis and characterization for addressing the exact functional requirements related to an end application. Also, we did a similar study for reduced Graphene Oxide (rGO).