Holistic Anti/Dewetting Design of Anti/Deicing Superhydrophobic Surfaces (ADISS)

Abstract

Anti/deicing superhydrophobic surfaces (ADISS) exhibit appealing capabilities of shedding water and delaying icing through the nonwetting Cassie−Baxter (C−B) state, whose maintenance should be a prerequisite for the practical applications of ADISS. However, the C−B state often suffers from inevitable degradation, while its recovery encounters significant challenges. Therefore, holistic antiwetting/dewetting designs deserve more attention to deal with multiscale water exposure of ADISS involving multifactorial interactions in time and space. Herein, three criteria were proposed for the design of nonwetting ADISS: high intrinsic contact angle, fine nanoscale structures, and appropriate spatial distribution of micro/nanostructures. By optimized air spraying, the target nanoengineered surfaces were constructed with a stable nano-Cassie state and improved anti-icing and antifrosting properties. Moreover, the dewetting ability to achieve the recovery of the C−B state was demonstrated, based on which a novel deicing mechanism involving coalescence-induced ice detachment has been revealed. This design method of ADISS is holistic and easy to execute, thus, having practical value in engineering applications.

Empowering Photovoltaic Panel Anti-Icing: Superhydrophobic Organic Composite Coating with In Situ Photothermal and Transparency

“…According to the Cassie–Baxter wetting state, the apparent contact area is composed of solid–liquid and liquid–gas interfaces. The apparent water contact angle (θ, 162.5 ± 1°) can be expressed as follows: cos θ = −1 + (1 + cos θ 0 ) f , − where f and θ 0 are the area fraction of the projected wetting area and Young contact angle of a Y6-coated glass surface (θ 0 = 99.7 ± 1° as shown in Figure S8; surface-SEM images of Y6-coated glass are shown in Figure S9), respectively. The calculated value f = 0.056 (air cushion ratio is about 94.4%) is relatively tiny in comparison to recent study results, indicating that the resultant Y6-NanoSH coating exhibited a very limited contact area with the water droplets, simultaneously implying that more air was entrapped in the rough structures of the Y6-NanoSH coating.…”