Self-cleaning of superhydrophobic nanostructured surfaces at low humidity enhanced by vertical electric field

Abstract

Self-cleaning is the key factor that makes superhydrophobic nanostructured materials have wide applications. The self-cleaning effect, however, strongly depends on formations and movement of water droplets on superhydrophobic nanostructured surfaces, which is greatly restricted at low humidity (< 7.6 g•kg −1 ). Therefore, we propose a self-cleaning method at low humidity in which the pollution is electro-aggregated and driven in the electric field to achieve the aggregation and cleaning large areas. The cleaning efficiency of this method is much higher than that of water droplet roll-off, and will not produce " pollution bands" . A simplified numerical model describing pollution movements is presented. Simulation results are consistent with experimental results. The proposed method realizes the self-cleaning of superhydrophobic nanostructured surfaces above dew point curve for the first time, which extends applications of superhydrophobic nanostructured materials in low humidity, and is expected to solve self-cleaning problems of outdoor objects in low humidity areas (< 5.0 g•kg −1 ).

Preparation and Anti-Icing Properties of Zirconia Superhydrophobic Coating

“…It has become an important additive for high-temperature resistant materials, ceramic insulation materials, and coatings [1][2][3]. Zirconia exhibits an excellent performance and using it to prepare superhydrophobic coatings can further enhance performance, such as frost suppression [4][5][6], anti-icing [7], and self-cleaning [8,9], and can be applied in aerospace [10,11], medical health [12], solar power generation [13], and other fields. The common methods for preparing super hydrophobic coatings include electrodeposition [14][15][16], laser processing [17,18], immersion [19,20], sol-gel [21], spraying [22,23], etc.…”

Design of an interface heating device based on polydivinylbenzene/SiO2/Bi2WO6and its visible light response performance for water purification

“…Superhydrophobic materials show an efficient oil–water separation capacity for the non-water-soluble oily wastewater discharged from chemical plants, 13–15 which are used in the field of durable coatings, 16,17 vapor escape channels, 18 anti-reflective 19 self-powered cathodic protection, 20 oil/water separation 21,22 and self-cleaning. 23 Ma et al 24 obtained the superhydrophobic polystyrene/SiO 2 fabric with a contact angle of 153° using the waste polystyrene solubilization technology and achieved oil–water separation. Wang et al 25 fabricated superhydrophobic sponges with a contact angle of 154° through immersed γ-Fe 2 O 3 @SiO 2 @PDMS suspension, which enabled the selective adsorption of n -hexane.…”

Direct Write Printing of Ultraviolet-Curable Bulk Superhydrophobic Ink Material

“…In recent years, superhydrophobic surfaces with a static water contact angle (CA) over 150° and a sliding angle (SA) less than 10° have become a hot topic in surface science, owing to their unique antiwetting characteristics and attractive applications in waterproofing, , self-cleaning, − antifouling, , and oil–water separation. − Such antiwetting characteristics are produced from the synergetic effect of low-surface-energy materials and multiscale surface roughness with both micro- and nanostructures. − Between the two, roughness holds greater significance in superhydrophobic surfaces, due to its ability to impede water droplets from infiltrating the grooves. To fabricate superhydrophobic surfaces, various techniques (e.g., spray coating, dip coating, and surface etching) have been developed to create proper roughness. ,,,− The resultant roughness requires further chemical modification with low-surface-energy components to form superhydrophobic surfaces.…”