Superhydrophobic surface has attracted great attention because of its potential applications. In this work, a facile method for fabrication of a superhydrophobic coating on pipeline steel surface is reported. A hierarchical structured coating with nanoflakes was fabricated via electrodeposition and solution-immersion, and then the coating achieved superhydrophobic with water contact angle about 157° and sliding angle around 3° after fluorination modification. The surface morphology and wettability changed with different experimental parameters were also investigated. The prepared superhydrophobic coating exhibited efficient self-cleaning and anticorrosion properties. Furthermore, the anti-scaling property of this superhydrophobic coating was confirmed since the CaCO 3 crystals on the superhydrophobic coating were mainly needlelike compared to the rhombohedral CaCO 3 crystals on the surface of steel substrate. This superhydrophobic coating maintained good long-term stability in air, and mechanical and thermal stability under certain environment. This superhydrophobic coating provided potential multifunctional applications, such as self-cleaning, corrosion resistance and anti-scaling properties, of deposition metal or alloy coating.
Xiuyong Chen,Jianhui Yuan,Jing Huang,Kun Ren,Yi Liu,Shaoyang Lu,Hua Li
This study aims to further enhance the anti-corrosion performances of Al coatings by constructing superhydrophobic surfaces. The Al coatings were initially arc-sprayed onto steel substrates, followed by deposition of polyurethane (PU)/nano-Al 2 O 3 composites by a suspension flame spraying process. Large-scale corrosion-resistant superhydrophobic PU/nano-Al 2 O 3 -Al coatings were successfully fabricated. The coatings showed tunable superhydrophilicity/superhydrophobicity as achieved by changing the concentration of PU in the starting suspension. The layer containing 2.0 wt.%PU displayed excellent hydrophobicity with the contact angle of ∼151° and the sliding angle of ∼6.5° for water droplets. The constructed superhydrophobic coatings showed markedly improved anti-corrosion performances as assessed by electrochemical corrosion testing carried out in 3.5 wt.% NaCl solution. The PU/nano-Al 2 O 3 -Al coatings with superhydrophobicity and competitive anti-corrosion performances could be potentially used as protective layers for marine infrastructures. This study presents a promising approach for fabricatiing superhydrophobic coatings for corrosion-resistant applications.
Gaoqi Wang,Ding Weng,Chaolang Chen,Lei Chen,Jiadao Wang
The aim of the study was to explore the synergistic effects of nanostructure size and surface treatment of TiO 2 coatings on its wettability and bacteria adhesion. The coatings were fabricated by TiO 2 particles with a diameter ranging from 25 nm to 300 nm. The surface wettability of coatings was tuned by chemical treatment. The anti-adhesion property of as-prepared coatings was evaluated with Streptococcus mutans in two types of solutions: phosphate buffer solution (PBS) and PBS with 1 wt% sucrose. The results show that particle size and surface treatment have significant influences on the wettability (with contact angles of 0–160°) and bacterial adhesion. The coating prepared by chemically modified 25 nm particles has a superhydrophobic property, and could inhibit bacterial adhesion in aqueous solutions with sucrose or not. The study also provides a facile, universal and low-cost process to fabricate anti-adhesion coating, which is applicable for diverse of substrates.
Superhydrophobic surfaces, such as lotus leaves, have attracted significant attention because of their excellent performance and potential application value. However, the micro-nano hierarchy on superhydrophobic surfaces is often vulnerable and easily broken from mechanical stress or chemical corrosion, which greatly inhibits its practical application and long-term service. This study presents a low-cost and scalable superhydrophobic coating based on an interpenetrated polymer network of polydimethylsiloxane (PDMS) and epoxy resin . The composite polymer matrix exhibits mechanical robustness as derived from the epoxy resin and low surface energy as derived from the PDMS. The superhydrophobic coating is obtained by dispersing fluoroalkyl-silane-modified SiO 2 in the solution containing the composite polymer . The multi-level hierarchical structure of SiO 2 aggregations and their strong bonding with the composite polymer gives the coating outstanding mechanical durability while maintaining superhydrophobicity after multiple cycles of sandpaper abrasion, tape peeling, and water impact tests. The chemical inertness of all components ensures its chemical stability, and the surface shows super repellency to strong acids and alkaline liquids (pH = 0–14). The coating also has excellent self-cleaning properties, which has potential applications in various industrial fields.