Fabrication of a Highly Stable Superhydrophobic Surface with Dual-Scale Structure and Its Antifrosting Properties

The stable superhydrophobic aluminum alloy surface with dual geometric architectures was prepared by a combination of simple processes of chemical etching, dip-coating, and modification of fluorosilicone. The Al surface with 20 min of acid etching and nanosilica dip-coating has the best superhydrophobicity, which showed water contact angles (WCAs) of >157 degrees and water sliding angles (SAs) of <1 degrees. The superhydrophobic surface showed excellent antifogging, antifrosting, and delayed icing performances, compared to hydrophobic and hydrophilic Al surfaces. Furthermore, the superhydrophobicity of as prepared surfaces is mechanically durable after 11 tape tests and 120 cm wear (under a pressure of 0.8 kPa). The strong interfacial interactions among the SiO2 nanoparticles, fluorosilicone-modified polyester resin, and the Al surface contributed to superior abrasion resistance. This method could provide a facile, low-cost, and stable route to fabricate a large-area superhydrophobic Al surface for application in various harsh environments.