Superhydrophobic nanocoatings: from materials to fabrications and to applications

Abstract

Superhydrophobic nanocoatings, a combination of nanotechnology and superhydrophobic surfaces, have received extraordinary attention recently, focusing both on novel preparation strategies and on investigations of their unique properties. In the past few decades, inspired by the lotus leaf, the discovery of nano- and micro-hierarchical structures has brought about great change in the superhydrophobic nanocoatings field. In this paper we review the contributions to this field reported in recent literature, mainly including materials, fabrication and applications. In order to facilitate comparison, materials are divided into 3 categories as follows: inorganic materials, organic materials, and inorganic-organic materials. Each kind of materials has itself merits and demerits, as well as fabrication techniques. The process of each technique is illustrated simply through a few classical examples. There is, to some extent, an association between various fabrication techniques, but many are different. So, it is important to choose appropriate preparation strategies, according to conditions and purposes. The peculiar properties of superhydrophobic nanocoatings, such as self-cleaning, anti-bacteria, anti-icing, corrosion resistance and so on, are the most dramatic. Not only do we introduce application examples, but also try to briefly discuss the principle behind the phenomenon. Finally, some challenges and potential promising breakthroughs in this field are also succinctly highlighted.

Robust superhydrophobic tungsten oxide coatings with photochromism and UV durability properties

“…[4] Up to now, there are many ways to increase surface roughness [5], among them the use of hydrophobic particles should be a facile and effective approach. [6] These particles usually form a coating on a surface by some means to change solid surface properties. In this way, various functional superhydrophobic surfaces can be achieved by changing the properties of particles.…”

On the Durability and Wear Resistance of Transparent Superhydrophobic Coatings

“…The review of literature indicates that one of the most commonly used nanoparticles in the fabrication of non-wettable coatings is SiO 2 nanoparticles [24]. They are extensively used in super-repellent polymer nanocomposite coatings but also in the fabrication of transparent non-wettable coatings.…”

Reversible switch between underwater superaerophilicity and superaerophobicity on the superhydrophobic nanowire-haired mesh for controlling underwater bubble wettability

“…[31][32][33][34][35] The water droplet on the mesh is at the Cassie wetting state, resulting in a high CA value and ultralow water adhesion. [36][37][38][39] The behavior of an underwater small bubble on this mesh was also investigated after the immersion of the mesh in water. When a bubble was released bellow the mesh, it would rise up until reach to the mesh.…”