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Updated: May 10, 2026

Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method
Published on: June 14, 2019
Three-phase contact force equilibrium of liquid drops at hydrophilic and superhydrophobic surfaces
Jianzhong Zhu1, Giovanni Zangari, Michael L Reed
1Department of Mechanical and Aerospace Engineering, University of Virginia, Charlottesville, VA 22904, United States.
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.
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