Durable Biomimetic Two-Tier Structured Superhydrophobic Surface with Ultralow Adhesion and Effective Antipollution Property

Abstract

Superhydrophobic surfaces with low adhesion have attracted great attention in recent years owing to their extensive applications. Enlightened by multifunctional rice leaves, a micro/nanobinary structured superhydrophobic surface was successfully fabricated on the Ti6Al4V substrate by photoetching, acid etching, alkaline etching, as well as fluorination treatments. Water droplets exhibited a Cassie impregnating wetting state on this superhydrophobic surface, under which the contact area fraction of the liquid-air interface caused by primary micron-scale stripped bumps (f p ) and secondary nanoflower-like structures (f s ) were calculated for the first time. The water adhesion force of this nonwetting surface was precisely measured as 7 μN, which was much lower than that (362 μN) of the original flat substrate and the previous reported surfaces. Moreover, this low-adhesive surface displayed good chemical stability after exposing to air, soaking in aqueous solutions (acid, alkaline, and salt), and cyclic icing/melting treatment. It also showed good mechanical durability after a series of abrasion treatments. Besides, this multifunctional superhydrophobic surface exhibited superior antipollution property to different kinds of contaminants. This multifunctional superhydrophobic surface displays a huge potential for industrial droplet transportation and self-cleaning applications.

Multiscale Microflower Structured Superhydrophobic Surface via Electrostatic Air Spray

“…Inspired by the “out of the silt without staining” property of lotus leaves in nature, superhydrophobic microstructure surfaces have remarkable application potential in self-cleaning, , anticorrosion, oil–water separation, − and droplet manipulation. , Currently, various methods have been proposed to construct low-adhesive and superhydrophobic surfaces, including templating, , laser, sol–gel process, electrostatic spinning, and electrochemical deposition . These methods are complex and rely on expensive equipment.…”

Armored Superhydrophobic Surfaces with Excellent Drag Reduction in Complex Environmental Conditions

“…A mechanically stabilized superhydrophobic surface has the potential to produce significant technological benefits in areas ranging from everyday life to marine transportation, such as self-cleaning, oil–water separation, − directional transportation, drag reduction, − and various other areas. − However, the lack of mechanical stability of SHSs is the primary obstacle to their widespread application. Therefore, researchers have used different strategies to improve the mechanical stability of surfaces. − Zhang et al prepared a three-layer multifunctional superhydrophobic coating inspired by skin, which maintains excellent superhydrophobicity even in harsh environments .…”

Oriented bouncing of droplets with a small Weber number on inclined one-dimensional nanoforests

“…Superhydrophobic surfaces have attracted great interest due to their abilities in anti-icing, self-cleaning, and heat transfer. [1][2][3][4][5][6][7] As has been reported, numerous organisms in nature, such as lotus leaves, rice leaves, butterfly wings, etc., exhibit superhydrophobic properties, [8][9][10][11] due to their low surface energy and rough surfaces with micro/nanostructures. On these surfaces, the micro/nanostructures not only can help in enhancing hydrophobicity, but also can adjust the direction of wettability through diverse asymmetries.…”