Variation in degrees of oxidation and exfoliation is one of the crucial areas in graphene oxide (GO) nanosheets research. Our findings suggest that emulsifying a sample of GO separates the nanosheets into fractions of differing degrees of oxidation. When GO sheets, water and oil are mixed together, more oxidized GO sheets suspend in a water phase, while the less oxidized material stabilizes the emulsion phase. This phenomenon provides the ability to control the electrical and thermal conductivity of the GO material by making stable emulsions. These more and less oxidized fractions are characterized by different techniques including XRD, FTIR, elemental analysis, and Raman spectroscopy. This fractionation method enables quantifying the oxidation dispersity number of GO (OD) in a batch and can be used to tune the density of oxygen functional groups on the GO sheets in a given sample. We describe this fractionation method, as well as demonstrate the effect controlling the extent of oxidation has on the properties of GO based applications including composite materials. In addition, this emulsion based fractionation method is pH dependent and can also be used to isolate a reduced graphene oxide like material with a lower value of Raman defect density. This isolated material has the capability of replacing the more expensive and topological defects inducing methods presently available.

Nanosheets and emulsion systems

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.