Nepenthespitcher inspired anti-wetting silicone nanofilaments coatings: Preparation, unique anti-wetting and self-cleaning behaviors

Abstract

Nepenthes pitcher inspired anti-wetting coatings, fluoro-SNs/Krytox, are successfully fabricated by the combination of fluoro-silicone nanofilaments (fluoro-SNs) and Krytox liquids, perfluoropolyethers. Fluoro-SNs with different microstructure are grown onto glass slides using trichloromethylsilane by simply repeating the coating step, and then modified with 1H, 1H, 2H, 2H - perfluorodecyltrichlorosilane. Subsequently, the Krytox liquid is spread on the fluoro-SNs coatings via capillary effect. The fluoro-SNs/Krytox coatings feature ultra-low sliding angle for various liquids, excellent stability, and transparency. The sliding speed of liquid drops on the fluoro-SNs/Krytox coating is obviously slower than on the lotus inspired superhydrophobic and superoleophobic coatings, and is controlled by composition of the coating (e.g., morphology of the fluoro-SNs, type of Krytox and its thickness) and properties of the liquid drops (e.g., density and surface tension). In addition, the self-cleaning property of the fluoro-SNs/Krytox coating is closely related to properties of liquid drops and dirt.