An amphiphobic graphene-based hydrogel as oil-water separator and oil fence material

Graphene-based hydrogel materials have attracted increasing attention in engineering applications such as oil-water separation. In this work, we report a novel, facile, environmental-friendly and cost-effective synthesis method for fluorographene nanosheets through Michael’s Addition reaction and the fabrication of amphiphobic LA/F/rGO hydrogel, based on a low-temperature hydrothermal process of partially reduced graphene oxide (rGO) and 1H,1H,2H,2H-perfluorodecanethiol (PF) in the presence of a reducing agent l-ascorbic acid (LA). The LA/F/rGO hydrogel has a low density of ∼19 mg/ml, with excellent thermal stability and regenerable adsorption capacity (up to 20 times its original weight) for various organic solvents. The as-prepared LA/F/rGO hydrogel shows intriguing oil repellant and oil bouncing behaviors underwater. Pre-soaking with water or oil allows selective and efficient separation of water or oil from their mixtures. The new LA/F/rGO hydrogel developed in this work has been demonstrated as a promising candidate for efficient adsorbent of oil pollutants in waste water treatment, oil/water separator and oil fence material. This work provides new insights into the development of novel graphene-based nanocomposite materials for oil-water separation and oil leaking, with a wide range of engineering and environmental applications.