Etching of wrinkled graphene oxide films in noble gas atmosphere under UV irradiation

We have studied the process of UV reduction of wrinkled grahpene oxide films, deposited on silicon substrate from ethanol suspension. In order to avoid destruction of graphene oxide via ozone formation from ambient air, samples were protected by argon atmosphere during UV irradiation. Using the analysis of back scattering spectra for medium energy ions, we have found that the UV irradiation mediated reduction process produced significantly decreased carbon content on the substrate surface. The decrease in the carbon content was accompanied by a smoothing of the films during reduction to graphene. We suppose that the observed effect is related to the oxidation of carbon atoms in the graphene scaffold of graphene oxide to carbon monoxide or dioxide by the oxygen from the graphene oxide (GO) itself. One has to consider this when developing a process for the preparation of graphene films using the UV-mediated reduction of graphene oxide.