Superhydrophobic thin films with nanostructured surface prepared with Au nanoparticle masks.

The hydrophobicity of a perfluoropolyether bisurethane methacrylate polymer film was investigated along with the formation of nano-hairs on its surface through reactive ion etching using gold nanoparticles (Au NPs) as masks. It was found that the hydrophobicity of the polymer film was strongly dependent on the number density of the nano-hairs which was determined by that of the Au NPs. The superhydrophobic surface was obtained when the number density was higher than 250 microm(-2). The effects of surface functionalization, Au NP immobilization, and etching time on the hydrophobicity of the polymer film were also examined extensively and discussed based on the results of the contact angle measurements and the scanning electron microscopy.