title: Electrical switching of wetting states on superhydrophobic surfaces: a route towards reversible Cassie-to-Wenzel transitions.
abstract: We demonstrate that the equilibrium shape of the composite interface between superhydrophobic surfaces and drops in the superhydrophobic Cassie state under electrowetting is determined by the balance of the Maxwell stress and the Laplace pressure. Energy barriers due to pinning of contact lines at the edges of the hydrophobic pillars control the transition from the Cassie to the Wenzel state. Barriers due to the narrow gap between adjacent pillars control the lateral propagation of the Wenzel state. We demonstrate how reversible switching between the two wetting states can be achieved locally using suitable surface and electrode geometries.
authors.affiliation: Physics of Complex Fluids, Fluidics and Interfaces, IMPACT and MESA+ Institute, Department of Science and Technology, University of Twente, P.O. Box 217, 7500 AE Enschede, The Netherlands.
authors.forename: G
authors.initials: G
authors.lastname: Manukyan
authors.forename: J M
authors.initials: JM
authors.lastname: Oh
authors.forename: D
authors.initials: D
authors.lastname: van den Ende
authors.forename: R G H
authors.initials: RG
authors.lastname: Lammertink
authors.forename: F
authors.initials: F
authors.lastname: Mugele