A Multifunctional Radiated Patterned Surface for Fog Collection, Oil/Water Separation, and Interfacial Floatability

Abstract

Multifunctional patterned surfaces with special wettability appeal to many researchers because of their potential applications in fog collection, microfluidics, and medical devices. To realize these functions and extend the corresponding application scopes, this article reports a multifunctional superhydrophobic radiated pattern on different wetting surfaces. Intriguingly, the hydrophilic surface with radiated pattern can quickly drive tiny water droplets toward more wetting regions, where water droplets move from center to the edge of a circle with a fog collection rate of about 3.075 g cm−2 h. However, the superhydrophobic surface with the radiated pattern triggers water to move from the edge to the center of a circle and achieves reverse transport. Importantly, the superhydrophobic surface can absorb oil and act as a micro‐reactor to realize oil/water separation. The surface can be transformed to be superhydrophilic by oxygen plasma etching and then recovers the superhydrophobicity by laser etching, which convinces the excellent restoration capacity. Furthermore, the surface composed of a superhydrophobic upper surface and a hydrophobic lower surface shows improved interfacial floatability. The findings offer a novel insight into the design of a multifunctional surface that not only enhances the fog collection but also realizes reverse liquid transport, and oil/water separation.

Research progress of bionic fog collection surfaces based on special structures from natural organisms

“…Patterned surfaces with special wettability have attracted increasing attention from researchers, due to their potential applications in fog collection, medical equipment, microfluidics, and other fields. To expand the functionality of patterned surfaces, our research group 130 further proposed a multifunctional superhydrophobic radiation pattern on different wetting surfaces ( Fig. 18f ).…”

“…18g ). 130 In addition, the superhydrophobic surfaces can serve as microreactors to achieve oil–water separation, which provided new insights for the design of multifunctional surfaces that not only enhance fog collection, but also achieve reverse liquid transport and oil–water separation.…”