Solar-driven, highly-efficient, and environmentally-friendly oil spill cleanup by a superelastic photothermal thermoplastic polyurethane monolith with aligned channels

Cleanup of crude oil spills is challenging due to its high viscosity. Reducing the viscosity of crude oil by elevating its temperature and thus promoting absorption is considered a promising and environmentally-friendly way to address this worldwide issue. Herein, we propose a photothermal superelastic thermoplastic polyurethane (TPU)-based monolith successively modified with MXene and polydimethysiloxane (PDMS) (P-MXene@TPU) with aligned channels for crude oil absorption and recovery. The well-oriented structures help reduce mass transfer hindrance and accelerate heat transfer, while MXene and PDMS endow the monolith with excellent photothermal conversion property and hydrophobicity, respectively. P-MXene@TPU monolith demonstrates superior oil absorption performance under solar irradiation as self-heating is realized to decrease the crude oil viscosity and promote its absorption rate. Particularly noteworthy is that P-MXene@TPU monolith can bear 300 compression cycles with a deformation of 9 % owing to the superelastic TPU skeleton and aligned channels. The stable compression performance and anti-fatigue property validate that the monolith is suitable for recovering crude oil by extrusion. Continuous crude oil recovery is achieved via a pumping device and solar irradiation (1.0 kW/m2) enhances the recovery rate by a factor of 18, as compared to the one without irradiation. Given the unique structural design and exceptional properties, this monolith provides a highly efficient approach for handing the crude oil spills.