Superamphiphobic surfaces with robust self-cleaning, abrasion resistance and anti-corrosion

Abstract

Superamphiphobic surfaces, capable of repelling both water and low-surface-tension liquids, are important for many applications. Simple and efficient way to fabricate superamphiphobic surfaces and their robust self-cleaning and abrasion resistance are key requirements for superamphiphobic surfaces to realize their applications. Here, superamphiphobic surfaces with extremely high contact angles (CAs) and low contact angle hysteresis for both water and low-surface-tension liquids are fabricated by a facile spray method of fluorinated multi-walled carbon nanotubes (F-MWCNTs). The fluorine content of F-MWCNTs is as high as 47.4%. The random accumulation of F-MWCNTs and the evaporation of solvent during spraying process creates appropriate surface roughness and micro-hills-like re-entrant microstructures. So, the CA for water and hexadecane on the surface reach 172.4˚ and 163.0˚, and sliding angles (SAs) are 1.2˚ and 4.3˚ respectively. Meanwhile, water and hexadecane are bouncing on this surface. Whether immersed in oil or exposed to air, the surface still possesses robust self-cleaning property. In addition, the introduction of spray adhesive greatly promotes the robustness of the coating, and the whole surface region maintains great superamphiphobic property after 40 abrasion cycle. Moreover, after soaking in acid solution with pH of 2 or alkaline solution with pH of 12 for 48 h, the CA and SA of water and hexadecane on this surface changes slightly, and this surface still holds outstanding superamphiphobicity. Furthermore, the reagents and devices required for the entire method are readily available, so it will be a potential candidate for the industrial production.