Multifunctional superhydrophobic coatings with self-cleaning and anti-fouling properties for corrosion protection of metals

Abstract

Superhydrophobic coatings have self-cleaning, antifouling, and anti-corrosion properties due to their unique surface properties, but their disadvantages such as poor durability, poor mechanical properties, and complicated preparation methods severely limit their practical applications. Here, superhydrophobic coatings with high abrasion resistance and long-lasting corrosion resistance were prepared by a simple spraying method using stearic acid-modified titanium dioxide nanoparticles (TiO2), polyphenylene sulfide (PPS) as the base material, and doped polyvinylidene difluoride (PVDF). The SA-TiO2 can provide low surface energy and rough structure, and the PPS itself has high mechanical strength and corrosion resistance properties. The PVDF doping can generate cross-linking inside the coating to improve the densification and mechanical strength of the coating, while the formation of irregular micrometer-sized protrusions can play a role in protecting the nano-surface. he synergistic effect of the various components results in an excellent mechanical stability of the coating, which remains superhydrophobic after a 400 cm sanding test. In addition, the coating has excellent corrosion resistance, and the electrochemical impedance spectroscopy (EIS) results show that the impedance modulus of the coating is as high as 21.99 kΩ·cm2. The coating has a hierarchical micro-nano structure, and shows excellent mechanical and corrosion resistance, which is of great potential for practical applications.