Super-Hydrophobic Graphene-Coated Thermoplastic Polyurethane Porous Monolith with Superior Photothermal Effect for Solar-Assisted Efficient Cleanup of Crude Oil Spill

Frequent occurrences of oil spill accidents have posed a serious threat to ecological system and human health, hence it is imperative to explore new-typed absorbents to clean up high-viscosity crude oil in an environmentally-friendly way. Herein we reported a reduced graphene oxide-wrapped and fluoroalkylsilane-modified thermoplastic polyurethane porous monolith (abbr. F-rGO@TPU monolith) with excellent reversible compressibility and fatigue resistance for solar-driven high-efficiency cleanup of crude oil. Owing to superior superhydrophobicity (water contact angle of 153°) and porosity (87.4%), the as-prepared F-rGO@TPU monolith possessed high saturated absorption capacity (6.5-53.7 g/g) and splendid oil/water separation efficiency (over 99.3%) for various low-viscosity oils/organic solvents. By virtue of the outstanding photothermal effect of reduced graphene oxide coating, the F-rGO@TPU monolith exhibited almost full absorption (96.0%) of solar spectrum (wavelength range of 250-2500 nm) and efficient light-to-heat conversion capability (achieving 80 °C in 5 min under 1.0 kW/m2 solar irradiation). The penetration process of crude oil drop on monolith surface manifested that the sorption rate of crude oil increased by 33 times under light on condition. More importantly, the solar-heated monolith could continuously and fast separate crude oil/water mixture by a pump-assisted device (crude oil flux of 510 kg/(m2·h)), revealing immense potential in oil spill remediation