Tailoring the Wetting Properties of Surface-Modified Nanostructured Gold Films

Nanostructured gold films with a dendritic morphology were synthesized by electrodeposition on porous Si surfaces. The films were modified by methyl-terminated self-assembled monolayers, resulting in the formation of superhydrophobic surfaces with a contact angle near to 180 degrees and undetectable hysteresis. Gradual smoothening of the dendritic features of the Au surfaces could be achieved by argon ion etching, resulting in a continuously tunable wetting angle. Below a contact angle of 150 degrees, these surfaces showed increased adhesion and significant contact-angle hysteresis.