Constructing Mechanochemical Durable and Self-Healing Superhydrophobic Surfaces

Abstract

Bioinspired superhydrophobic surfaces have attracted great interest due to their special functions and wide applications. However, it is still a big challenge to construct a durable superhydrophobic coating for large-scale applications due to its easy destruction by the mechanochemical attack. In this mini-review, we present the state-ofthe-art developments in the rational design of mechanochemical durable and self-healing superhydrophobic surfaces. First, the mechanically durable superhydrophobic surfaces are constructed to endure mechanical damage by adjusting the surface morphology and increasing the binding force between the substrates and the modified materials. Second, chemical damages also have been taken into consideration to develop chemically robust superhydrophobic surfaces, such as chemical etching, ultraviolet (UV)-light irradiation, and bioerosion, etc. Third, endowing superhydrophobic coatings with self-healing function can effectively improve the durability and prolong the lifespan of the coatings by releasing low-surface-energy agents or regenerating topographic structures. Finally, the challenges and future perspectives in developing super durable bioinspired superhydrophobic surfaces by structure design and chemistry control are discussed. The innovative points provided in this mini-review will provide deep fundamental insight for prolonging the lifetime of the superhydrophobic surfaces and enable their practical applications in the near future.

Regenerative Superhydrophobic Paper Coatings by In Situ Formation of Waxy Nanostructures

“…Mechanically stable superhydrophobic materials can either be obtained using hard materials such as metals, by increasing the binding force between the material and substrate with covalent bonding for instance or with coating systems that retain both, the topography and hydrophobic surface chemistry, after material abrasion. [ 47–52 ] Easy repairable superhydrophobic materials enable a simple method to deposit new material for instance via spray coating. [ 40,50,53 ] Finally, self‐healing materials are able to restore their superhydrophobic properties without any intervention (autonomous self‐healing) or by human intervention respectively by the action of an external trigger (non‐automatic).…”

“…[ 54 ] There are many approaches where the coating component with low surface energy is stored in a rough structure and can migrate to the damaged surface during such a self‐healing process. [ 48,49,52,55–59 ] However, mechanical durability is again limited by the destruction of the topography. [ 48 ] Only few investigations focus on regenerating such a micro‐/ nanotopographic structure after it has been destroyed.…”

“…[ 48 ] Only few investigations focus on regenerating such a micro‐/ nanotopographic structure after it has been destroyed. [ 48,52,58–61 ] According to the above definitions, such regenerative coatings belong to the class of nonautomatic self‐healing materials, and may also be referred to as “stimulus responsive materials.” Such materials that are capable to in situ form effective nanostructures as well as possess the capability to regenerate such structures by an external trigger, are of great interest. [ 48 ] Note, only those materials and regeneration processes which are compatible with existing coating technologies, in which the recyclability of a paper material is not impaired and in which ecologically questionable substances such as organic fluorine compounds are avoided, may have good chances to be considered for furture paper applications.…”

Superhydrophobic graphene-based materials with self-cleaning and anticorrosion performance: An appraisal of neoteric advancement and future perspectives

“…Mechanical durability is one of the crucial components in meeting the real-world application. The fabrication of a durable superhydrophobic material as a coating is an important aspect as it easily gets tampered by mechanical and chemical action [ 91 ]. Mechanical abrasion tests were carried out in graphene oxide and nickel coated superhydrophobic surfaces.…”

Ultrasonication‐Assisted Waterborne Synthesis of Self‐Restorable Superhydrophobic Surfaces with Prolonged Lifespan in Oil Collection

“…Recently, seeking for superhydrophobic surfaces with a function that enables to self‐restore/heal their superhydrophobicity after the damages evokes an increasing interest not least because it proposes a plausible way to improve the durability and sustainability of the superhydrophobic surface so as to effectually prolong the lifespan of the materials in practice. [ 20–33 ] In design, the strategies to restore superhydrophobic surfaces rely on the recovering of either the low‐interfacial‐energy surface chemical composite or the hierarchical surface morphology. The former strategy requires the storage of the low‐interfacial‐energy chemicals within the coatings.…”