title: A highly efficient, stable, durable, and recyclable filter fabricated by femtosecond laser drilling of a titanium foil for oil-water separation.
abstract: It has been a long standing challenge to efficiently separate oil and water since prehistoric times, and now it has become even more desirable in oily wastewater purification and oil spill cleanup. Here we introduce a super oil-water separation filter with superhydrophilicity and underwater superoleophobicity, fabricated using femtosecond laser micro-hole drilling of a titanium foil. Such a simply-made filter, without any modification, can achieve a separation efficiency exceeding 99% in eight typical oil-water mixtures. It remains highly efficient after 40 cycles of recycling and after suffering erosion by corrosive media. Furthermore, the used filter, polluted with oil, could be recovered by ultraviolet illumination. The flux of filtered water is tunable by simply selecting the aperture of the microhole or the spacing between adjacent microholes. Such advanced functionality is due to roughness and the TiO2layers on the ablated surface during fabrication. With superhydrophilic and superoleophobic surfaces, this oil-water filer is also suitable for applications in anti-fouling, anti-smudge, anti-fog, and self-cleaning.
authors.affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
authors.forename: Sen
authors.initials: S
authors.lastname: Ye
authors.affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Cao
authors.affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
authors.forename: Qingsong
authors.initials: Q
authors.lastname: Wang
authors.affiliation: Laser Micro/Nano Fabrication Laboratory, School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, People's Republic of China.
authors.forename: Tianyuan
authors.initials: T
authors.lastname: Wang
authors.affiliation: School of Power and Mechanical Engineering, Wuhan University, Wuhan 430072, China.|Nuclear Engineering and Radiological Sciences, University of Michigan, Ann Arbor, MI 48109, USA.|Department of Mechanical, Aerospace and Nuclear Engineering, Rensselaer Polytechnic Institute, Troy, NY 12180, USA.
authors.forename: Qing
authors.initials: Q
authors.lastname: Peng