Covalently intercalated graphene oxide for oil-water separation

We report the transformation of hydrophilic graphene oxide (GO) sheets into superhydrophobic nanomaterial by direct esterification with epoxy-functionalized polyhedral oligomeric silsesquioxane (ePOSS). The covalently functionalized GO-ePOSS composite shows superhydrophobicity with a water/air contact angle of similar to 145 degrees. The highest dispersion limits for GO in selected organic solvents are obtained in the literature. The dispersion of GO-ePOSS can be extended to solvents with Hansen solubility parameters as low as 3.4. Efficient oil-water separation is also demonstrated by using a GO-ePOSS membrane. (C) 2014 Elsevier Ltd. All rights reserved.