Fabrication of water-resistant and abrasion- resistant superhydrophilic coatings

Abstract

Superhydrophilic coatings show promising applications in the anti-fogging and self-cleaning fields. However, the application of transparent superhydrophilic coatings faces two challenges: abrasion and water immersion leading to loss of superhydrophilicity. Herein, we contribute Halloysite nanotubes (HNTs) to enhancing abrasion resistance by integrating into network-like structures within coatings, and water resistance by adsorbing sodium alkenyl sulfonate (AOS) facilitated by the positive charge within their cavities, respectively. Hydrolyzed tetraethyl orthosilicate (TEOS) as crosslinking agents combines with the abundant hydroxyl groups (Si-OH) on the surface of HNTs nanotubes and glass substrate to form a three-dimensional network structure. The results demonstrate that the designed HNTs tube coatings have strong abrasion and water resistance accompanied by anti-fogging and self-cleaning properties, which can withstand 800 cycles of Taber abrasion under a load of 250 g, and 90 min of immersion in boiling water. Furthermore, the coated surface exhibited negligible contamination after 153 days in an outdoor environment, which indicates a commendable long-term self-cleaning capability. Therefore, the introduction of HNTs nanotubes can provide a useful strategy for the development of superhydrophilic coatings for anti-fogging and self-cleaning with excellent abrasion and water resistance.