title: Polydimethylsiloxane-Based Superhydrophobic Surfaces on Steel Substrate: Fabrication, Reversibly Extreme Wettability and Oil-Water Separation.
abstract: Functional surfaces for reversibly switchable wettability and oil-water separation have attracted much interest with pushing forward an immense influence on fundamental research and industrial application in recent years. This article proposed a facile method to fabricate superhydrophobic surfaces on steel substrates via electroless replacement deposition of copper sulfate (CuSO4) and UV curing of vinyl-terminated polydimethylsiloxane (PDMS). PDMS-based superhydrophobic surfaces exhibited water contact angle (WCA) close to 160° and water sliding angle (WSA) lower than 5°, preserving outstanding chemical stability that maintained superhydrophobicity immersing in different aqueous solutions with pH values from 1 to 13 for 12 h. Interestingly, the superhydrophobic surface could dramatically switch to the superhydrophilic state under UV irradiation and then gradually recover to the highly hydrophobic state with WCA at 140° after dark storage. The underlying mechanism was also investigated by scanning electron microscopy, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. Additionally, the PDMS-based steel mesh possessed high separation efficiency and excellent reusability in oil-water separation. Our studies provide a simple, fast, and economical fabrication method for wettability-transformable superhydrophobic surfaces and have the potential applications in microfluidics, the biomedical field, and oil spill cleanup.
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Xiaojing
authors.initials: X
authors.lastname: Su
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Hongqiang
authors.identifier: http://orcid.org/0000-0002-1191-2203
authors.initials: H
authors.lastname: Li
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Xuejun
authors.initials: X
authors.lastname: Lai
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Tao
authors.initials: T
authors.lastname: Liang
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Yuchun
authors.initials: Y
authors.lastname: Feng
authors.affiliation: College of Materials Science and Engineering, South China University of Technology , Guangzhou 510640, People's Republic of China.
authors.forename: Xingrong
authors.initials: X
authors.lastname: Zeng
keywords: UV irradiation; oil−water separation; polydimethylsiloxane; reversibly extreme wettability; superhydrophobic surfaces