Facile synthesis of fluorinated polydopamine/chitosan/reduced graphene oxide composite aerogel for efficient oil/water separation

In recent years, reduced graphene oxide (rGO) has attracted wide attention from researchers due to its excellent physicochemical properties and rich surface chemistry. Inspired by the innate adhesive property of dopamine, a facile and environmentally-friendly approach was developed to fabricate reduced graphene oxide/polydopamine composite aerogel reinforced by chitosan and modified by 1H,1H,2H,2H-perfluorodecanethiol (PFDT). During the preparation process, a polydopamine (PDA) film was first anchored on reduced graphene oxide (rGO) nanosheets via dopamine self-polymerization. By means of hydrothermal treatment, immersion and freeze-drying process, rGO nanosheets modified by PDA were self-assembled into a 3D porous structure, and the chitosan/reduced graphene oxide composite aerogel (CGA) was synthesized. Subsequently, PFDT reacted with PDA film to fabricate perfluorinated superhydrophobic polydopamine/chitosan/reduced graphene oxide composite aerogel (fCGA). The CGA possesses super-amphiphilicity in air and superoleophobicity underwater, while fCGA exhibits superhydrophobicity. Both of them have oil/water separation behavior, indicating that the aerogels are promising materials for the treatment of oil-spill accidents and oily wastewater.