Fabrication of zinc oxide/polydimethylsiloxane composite surfaces demonstrating oil-fouling-resistant superhydrophobicity

A novel approach is described for preparing anti-oil-fouling superhydrophobic surfaces. These are produced via the coating of textured hydrophobic zinc oxide on polydimethylsiloxane films to form composite coatings. The surfaces showed superhydrophobic as well as superoleophilic wetting with measured contact and sliding angles for water near 160° and less than 5°, respectively, and contact angles of less than 5° for dodecane. It is demonstrated that subsequent to the fouling of structured surfaces with significant levels of an alkane liquid (oil), the oil is rapidly self-removed, restoring superhydrophobic behavior. Furthermore these protective surfaces can be thermally regenerated for repeated use. This approach is distinct from those reported previously, which rely on expensive fluorochemicals to produce superamphiphobic surfaces. It is believed that the presented approach holds promise in the design of practical anti-oil-fouling superhydrophobic technology.