From rolling ball to complete wetting: the dynamic tuning of liquids on nanostructured surfaces

In this work, for the first time, a dynamic electrical control of the wetting behavior of liquids on nanostructured surfaces, which spans the entire possible range from the superhydrophobic behavior to nearly complete wetting, has been demonstrated. Moreover, this kind of dynamic control was obtained at voltages as low as 22 V. We have demonstrated that the liquid droplet on a nanostructured surface exhibits sharp transitions between three possible wetting states as a function of applied voltage and liquid surface tension. We have examined experimentally and theoretically the nature of these transitions. The reported results provide novel methods of manipulating liquids at the microscale.