Self-floating Ti₃C₂ MXene-coated polyurethane sponge with excellent photothermal conversion performance for peroxydisulfate activation and clean water production

The self-floating Ti3C2 MXene-coated polyurethane sponge (MXene@PU module) was prepared via the simple coating operation for thermal activation of peroxydisulfate (PDS) and production of clean water. Coating MXene on the surface of PU significantly improved the degradation of model pollutant carbamazepine (CBZ) compared with PU alone under simulated solar radiation. Because of the excellent photothermal conversion performance of Ti3C2 MXene and the unique double-deck structure of MXene@PU module, the interfacial temperature of MXene@PU module reached about 140 degrees C, far higher than that of PU (about 82 degrees C). Radical identification experiments demonstrated that both hydroxyl radical and sulfate radical contributed to the degradation of organic pollutant. Addition of Cl-, HPO42-, HCO3- and natural organic matter in solution generated inhibitory effect on CBZ degradation. The prepared MXene@PU module exhibited excellent stability after long-time experiment. Importantly, the interfacial evaporation process produced abundant recycled water and no pollutant was detected in recycled water. This study provides a feasible way to utilize the renewable solar energy for removal of organic pollutants and production of clean water.