Electrowetting-induced dewetting transitions on superhydrophobic surfaces.

We develop and demonstrate the use of electrowetting to achieve the dewetting (Wenzel-to-Cassie transition) of superhydrophobic surfaces. We effect this transition by means of an opposing flat plate and a three-electrode system; the liquid droplet is completely pulled out of its wetted Wenzel state upon the application of a suitable voltage. We also experimentally quantify the dissipative forces preventing the dewetting transition. The energy associated with these nonconservative forces is comparable to the interfacial energies.