Computationally Supported Neutron Scattering Study of Parent and Chemically Reduced Graphene Oxide

Synthetic graphene oxide (GO) as well as the product of its reducing performed in the regime of hydrogenolysis (rGO) were studied by both elastic and inelastic neutron scattering at low and room temperature conditions. The neutron diffraction patterns were analyzed to confirm stacking structures of both species consisting of 2-3 and ∼7 layers of microsize lateral dimension and the interlayer distances of 7 and 3.5 Å, respectively. The inelastic incoherent neutron scattering spectra were analyzed in the frame of the computationally supported one-phonon amplitude-weighted density of vibrational states G(ω) approximation. Calculations of G(ω) spectra were performed in the framework of semilocal density functional theory. The computational models were adjusted to the atom mass content of both GO and rGO species. The presented study has revealed the retained water in the freshly made GO, corresponding to the relatively low humidity, which further reacts with the oxygen-containing groups at the GO basal planes. The reaction results in the formation of hydroxyls chemically bound to the GO core in the course of the prolong storage of the product under ambient conditions. The analysis of the rGO G(ω) spectrum has disclosed the chemical composition of its circumference attributing the latter to sets of CH units with a minor presence of atomic oxygen. © 2015 American Chemical Society