Superhydrophobic graphene aerogel beads for adsorption of oil and organic solvents via a convenient in situ sol-gel method

Abstract

Herein, superhydrophobic graphene aerogel beads (SGA beads) were fabricated by one-step in situ sol-gel method in coagulation bath containing octadecylamine (ODA). Through modification with ODA, long alkyl chain with low surface energy was grafted onto graphene oxide (GO) sheets and many nanoscale wrinkles were observed on the surface of graphene sheets, which afford a remarkable water contact angle of 153°. The SGA beads possessed low density (14.4 mg/cm3), high porosity (96.9%), and specific surface area of 18.49 m2/g. As expected, this macro-porous network structure presented excellent absorption capacity for oil and organic solvents, with a value of 52-178 g/g. Furthermore, the SGA beads displayed good elasticity (rebound under 70% strain) and oil/water selectivity. The adsorbed organic solvents could be recovered by continuous absorption-combustion process. Therefore, such a simple fabrication process and superior properties make the resulting SGA beads present great application potential towards spill oil and organic pollution cleanup.