Chemical vapor deposition of transparent superhydrophobic anti-Icing coatings with tailored polymer nanoarray architecture

Abstract

Transparent superhydrophobic coatings are highly desirable in outdoor optoelectronic devices for their anti-wetting, self-cleaning, and anti-icing abilities. Superhydrophobicity requires surface microstructure that accommodates trapped air in between the liquid–solid interface, which would, however, compromise coating transparency. This trade-off can be balanced by creating tailored microtopography on low surface energy coating, which is usually achieved by rather complex multi-step procedures. Herein, we demonstrate a facile one-step method that creates transparent superhydrophobic coatings with tailored nanocone array structures via initiated chemical vapor deposition (iCVD). This novel iCVD process employs condensed nanosize monomer droplets as nucleation centers and subsequently grows vertically aligned polymer nanocones. The height and density of the nanocones can be well controlled by adjusting the deposition conditions. The resultant polymer nanocone array coatings (NC) exhibit better water repellency and anti-icing performance as well as higher light transmittance than iCVD rough coatings (RC) with irregular surface microstructure. The icing delay time of coatings with optimized nanocone array structure reached a remarkable 540 s, which is 38.5 and 2.2 times that of pristine and RC-coated glass. Further tests reveal good self-cleaning, excellent durability and stability of the NC coating, indicating potential for outdoor optoelectronic device protection.