Waterborne Recoatable Transparent Superhydrophobic Coatings with Excellent Self-Cleaning and Anti-Dust Performance

Superhydrophobic surfaces have attracted tremendous attention due to their intriguing lotus-leaf-like water-repelling phenomenon and wide applications, however, most superhydrophobic coatings are prepared with environmentally unfriendly organic solvents and suffer from poor mechanical strength. To solve these issues, waterborne recoatable superhydrophobic (WRSH) coatings are developed based on a novel self-synthesized water-soluble fluorinated acrylic polymer and hydrophobic modified silica nanoparticles. The trade-off between waterborne and superhydrophobicity is well mediated by protonation and deprotonation of the fluorinated acrylic polymer. When the coating is damaged, it can be easily repaired and recoated using WRSH coatings without the need to remove the damaged superhydrophobic layer, providing a sustainable and environmentally friendly solution for maintaining a superhydrophobic surface. The coating exhibits good mechanical properties with the WRSH coating maintaining mechanical stability even after abrasion with 2000 mesh sandpaper for 20 m or impact from 100 g of sand. Additionally, the visible light transmittance of WRSH coating glass reaches as high as ≈94.0%, which is superior to the bare glass of ≈91.7%. Moreover, the WRSH coatings exhibit excellent self-cleaning performance and anti-dust performance when applied on solar panels.