Photoinduced Superwetting Single-Walled Carbon Nanotube/TiO2 Ultrathin Network Films for Ultrafast Separation of Oil-in-Water Emulsions

• Published in: ACS nano 2014-06, Vol.8 (6), p.6344-6352
• Main Authors: Gao, Shou Jian, Shi, Zhun, Zhang, Wen Bin, Zhang, Feng, Jin, Jian
• Format: Article
• Language: English
• ISSN: 1936-0851; 1936-086X
• DOI: 10.1021/nn501851a

A SWCNT/TiO2 nanocomposite ultrathin film that has superhydrophilic and underwater superoleophobic properties after UV-light irradiation is successfully prepared by coating TiO2 via the sol–gel process onto an SWCNT ultrathin network film. The robust and flexible SWCNT/TiO2 nanocomposite films with a thickness and pore size of tens of nanometers can separate both surfactant-free and surfactant-stabilized oil-in-water emulsions in an ultrafast manner with fluxes up to 30 000 L m–2 h–1 bar–1, which is 2 orders of magnitude higher than commercial filtration membranes with similar separation performance, and with high separation efficiency. Most importantly, the films exhibit excellent antifouling and self-cleaning performance during multiple cycles with the aid of the photocatalytic property of TiO2 nanoparticles. This work provides a route for designing ultrathin and superwetting films for effective separation of oil-in-water emulsions. The SWCNT/TiO2 ultrathin film is potentially useful in treating emulsified wastewater produced in industry and daily life and for purification of crude oil and fuel.