Gecko-inspired synthesis of superhydrophobic ZnO surfaces with high water adhesion

This paper reports an easy means to imitate the “gecko’s feet” by constructing ZnO nanorods on Zn foil through a simple and inexpensive solution chemistry approach. The ZnO nanorods with various densi- ties have been fabricated by controlling the synthesis temperature and time. After being modified with fluoroalkylsilane, the ZnO nanorods surfaces show analogous superhydrophobic property and tunable high water adhesion. The as-prepared superhydrophobic ZnO surface allows water droplets to pin on the surface without any movement, even if it is tilted to a vertical position or turned upside down. Further- more, the adhesive force of the surface is found to be strong enough to catch a water droplet that rolls down quickly from a tilted low adhesive superhydrophobic surface.