Fabrication of PDMS/FA superhydrophobic coatings and its self-cleaning and anti-icing performance

Abstract

Superhydrophobic coatings have garnered immense attention in recent years. Nevertheless, the creation of superhydrophobic coatings is often associated with high production costs and comparatively intricate fabrication processes. In this paper, we utilize cheap and easily available ultrafine fly ash(FA) as the main raw material to replace the expensive filler substances traditionally used for constructing rough structures, and Polydimethylsiloxane(PDMS) as a low surface energy modification to construct FA-based superhydrophobic coatings by a simple spraying method. The PDMS/FA coating surface exhibits a water contact angle(WCA) of 157.65°and a water sliding angle(WSA) of 2.00° The irregular morphology of the FA is conducive to forming a rough texture on the coating surface, which captures more air, leading to the formation of a stable air layer. Molecular dynamics (MD) simulations provide an insight into the anti-wetting mechanism of the superhydrophobic surface through an analysis of energetic and dynamic properties. PDMS/FA coatings remain superhydrophobic at 150 °C, in UV, and in varying pH environments. In addition, PDMS/FA coatings offer excellent mechanical, self-cleaning and anti-icing properties. This innovative approach to superhydrophobic coating, utilizing solid waste material as a basic material, demonstrates potential applicative value in fields such as self-cleaning and anti-icing.