Directional droplet-actuation and fluid-resistance reduction performance on the bio-inspired shark-fin-like superhydrophobic surface

The tunable of fluid transport on solid surface plays a significant role for self-cleaning and drug-saving fields. It effectively prevents the corrosion and declines the fluid resistance induced by the rushing water and accumulated microorganisms on the hull surface. To more effectively combat these problems, herein, we provide a new strategy, a superhydrophobic shark-fin-like bionic surface. Anisotropic characteristic of this novel structure lead to the different de-pinning force in the opposite direction for the water droplet. The superhydrophobicity of the shark-fin-like embossment is from the "air layer" formed by the ZnO nano-structure. This novel composited surface can effectively realize the directional droplet-actuation and fluid-resistance reduction performance. Droplets and fluid will move more easily along the special direction on the shark-fin-like surface. Moreover, the substrate material is flexible and easy to mass production. We believe that this work will give a significant scientific insight to self-cleaning surface and hull design. (C) 2019 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.