Thermoplastic polyurethane/titania/polydopamine (TPU/TiO 2 /PDA) 3-D porous composite foam with outstanding oil/water separation performance and photocatalytic dye degradation

With the rapid development of the chemical industry, large amounts of industrial organic pollutants have constituted a huge threat to the ecological environment. The 3-D porous TPU/TiO 2 /PDA composite foam with outstanding oil/water separation and photocatalytic performances was successfully prepared. Its morphology, chemical composition, surface wettability, mechanical properties, oil/water separation, and photocatalytic performances had been systematically studied by SEM, FTIR, XRD, XPS, Raman, XPS, TGA, contact angle instrument, and ultraviolet spectrophotometer. The results showed that TPU/TiO 2 /PDA composite foam can remove water and oil for various oil/water mixtures and emulsion with outstanding separation performance only under the gravitational force. The water and oil separation flux can reach 21,035 L/m 2 ·h and 14,500 L/m 2 ·h, respectively. The highest separation efficiency reach to 99.6% for petroleum ether/water. It also can continuously separate the oil and water from various water/oil mixtures with the assistance of the pump; after 10 cycles, it maintains large separation efficiency of 98.5%. Moreover, the RhB removal rate reached up to 96% only after irradiation 1 h under UV light. These results manifested that the prepared multifunctional TPU/TiO 2 /PDA composite foams have great application prospect in oil/water separation fields, providing a new idea for fabricating 3-D porous composite foams with multifunctionality. A novel type of 3-D porous TPU/TiO 2 /PDA composite foam with multifunctional applications was successfully designed and prepared. It exhibits excellent performance for oil/water separation and photocatalytic degradation of organic dye. Graphical abstract