Effect of nanostructure on the surface dipole moment of photoreversibly tunable superhydrophobic surfaces.

Fluorinated azobenzene-modified nanoporous substrates were fabricated such that the surface properties were photoreversibly converted between superhydrophobicity and superhydrophilicity as a result of UV irradiation. This result was attributed to the enhanced surface roughness of the nanostructured surface, which supplied sufficient free space within the monolayer for the tethered azobenzenes to facilely isomerize.