Fabrication of an intelligent superhydrophobic surface based on ZnO nanorod arrays with switchable adhesion property

The superhydrophobic ZnO surface possessing water adhesive reversibility is fabricated by a facile method. The as-prepared surface is low adhesive; however, after being irradiated by UV light through a photomask, it becomes highly adhesive. A water droplet can suspend on the irradiated surface. Further annealing the irradiated surface, water droplets can roll on the surface again. Reversible transition between the high adhesive pinning state and low adhesive rolling state can be realized simply by UV illumination and heat treatment alternately. The adhesion transition is attributed to the adsorption/desorption of surface hydroxyl groups and the organic chains rearrangement on the top surfaces of ZnO.