Electrically tunable superhydrophobic nanostructured surfaces

In this work, we discuss dynamic electrical control of the wetting behavior of liquids on nanostructured surfaces spanning the entire possible range from superhydrophobic behavior to nearly complete wetting. It is demonstrated that a droplet of liquid can be reversibly switched between the superhydrophobic "rolling ball" state and the hydrophilic immobile droplet state by the application of electrical voltage and current. The nature of the transition mechanism is studied both experimentally and theoretically. The reported results provide novel methods of manipulating liquids at microscale. (c) 2005 Lucent Technologies Inc.