Switching from superhydrophobicity to underwater superoleophobicity
Smart surfaces with switchable water/oil wettability has great research and application value. In a paper, scientists present transparent smart surfaces with pH-responsive water wettability in air and oil wettability in water via grafting pH-responsive block copolymers on an inverse opal film.
The resulting transparent surface not only shows superhydrophobicity in air but also displays underwater superoleophobicity after treatment with acid.
Good abrasion resistance and chemical stability
This transition in wettability is reversible and can be repeated multiple times through adjusting the pH value on the surface. Moreover, this smart surface sustains its superhydrophobicity and underwater superoleophobicity after being abraded with sand or immersed into NaCl aqueous solutions for 7 days. This transparent surface may be useful for the development of swimsuits, microfluidic valves, automotive glass and solar cells.
The study is published in: Materials & Design, Volume 135, 5 December 2017.
