Using First-Principles Calculations to Investigate the Effect of Oxidation on Graphene Spectroscopic Properties

Molecular vibrational spectroscopy is an important method to study the atomic structure of graphene oxide. To investigate the effect of oxidation on the structural and spectroscopic properties of graphene, pseudo-potential density functional theory calculations were applied. Several models were considered, covering the most relevant functional groups that have been postulated to decorate the surface of graphene layer on carbon materials. Different arrangements of these units produced a range of vibrational spectra. The results suggested the possibility of creating and tuning graphene's spectroscopic properties by varying the oxidation levels and the relative position of epoxy and hydroxyl functional groups on the surface. Spectra characteristics for local structures from this work shed light on the structural and vibrational properties of graphene oxide, which could be very helpful for experimental groups to further understand the structure of graphene oxide and reduce graphene oxide.