Simple and Affordable Way To Achieve Polymeric Superhydrophobic Surfaces with Biomimetic Hierarchical Roughness

Abstract

A water contact angle greater than 150° together with a sliding angle less than 10° is a special surface phenomenon that appears on superhydrophobic surfaces. In this paper, a brief introduction of the development history and present research on superhydrophobic surfaces was given. Polymeric superhydrophobic surfaces with biomimetic hierarchical roughness were fabricated by a simple method of hot embossing without any chemical treatments. Stainless steel meshes with different mesh numbers were used as template. Moreover, the influences of processing parameters, including mesh number, mold temperature, and pressure, were deeply investigated. Hierarchical microplatforms, microfibers, and oriented arrayed nanowrinkles structure on them, which were resembled with the nanowrinkles structure and hierarchical roughness on a red rose petal, were observed by a scanning electron microscope. A water contact angle of 154° can be achieved after parameter optimization. The method proposed in this study offered a fine and affordable choice for the fabrication of polymeric superhydrophobic surfaces. With the rapid development of functional applications in micro- and nanodevices, this method will show greater superiority in large-area and large-scale production due to its advantages of low cost, high efficiency, and high reliability.