title: Three-phase contact force equilibrium of liquid drops at hydrophilic and superhydrophobic surfaces.
abstract: Hydrophilic and superhydrophobic surfaces were obtained by modifying a dendritic Au surface with carboxyl- or methyl-terminated self-assembled monolayers, respectively. The hydrophilic surface generates capillary forces which induce water flow through the grooves defined by the dendritic structure, resulting in a halo structure; the superhydrophobic surface on the other hand completely repels water drops. The contrasting behaviors exhibited by the two surfaces with nominally identical morphology but different surface chemistry are explained semi-quantitatively in terms of the equilibrium of surface forces developing at the three-phase (air-solid-water) contact lines.
authors.affiliation: Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, United States.
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Zhu
authors.forename: Giovanni
authors.initials: G
authors.lastname: Zangari
authors.forename: Michael L
authors.initials: ML
authors.lastname: Reed