Dispersion of alkyl-chain-functionalized reduced graphene oxide sheets in nonpolar solvents.

Alkyl chains were grafted onto reduced graphene oxide sheets to allow their dispersion in toluene, a common and representative nonpolar solvent. The grafting occurred on a variety of oxygen-containing functionalities already present on reduced graphene oxide, such as hydroxyl and epoxide groups. The structure and the defect density of the sheets were not significantly altered during the synthesis. When dispersed in water-toluene mixtures, phase transfer from the aqueous to the organic phase was observed upon grafting. In addition, the dry powder obtained readily disperses in common organic solvents without the assistance of any sonication treatment.