Fabrication of robust high-transmittance superamphiphobic coatings through dip-coating followed by spray-coating

摘要

Solid silica nanoparticles (ca. 20 nm), hollow silica nanoparticles (ca. 60 nm) and a binder solution composed of silica nanosheets and acid-catalyzed silica sol were used to fabricate superamphiphobic coatings with high transmittance and excellent robustness via a sequential combination of easy dip-coating and spray-coating processes. The water contact angle (WCA) and ethylene glycol contact angle (OCA) of the coating were 171 degrees and 150 degrees, respectively. The maximum transmittance of coated glass reached 96.2% at the wavelength of 550 nm, which is much higher than that of blank glass (91.2%). The coatings demonstrated excellent mechanical robustness. They fell at the 5A level in a tape adhesion test based on ASTM D3359-93, and could endure a 5H pencil scratching test. They also retained their superhydrophobicity after tape peeling test, sand abrasion test, water drop-impact test, and outdoor durability test for five months.