An effective approach to fabricate the corrosion resistance of superhydrophobic ZnO/Ni composite coating on carbon steel substrate

In this study, the carbon steel substrates were coated with nickel (Ni), zinc oxide (ZnO) and ZnO/Ni coatings by electrodeposition approach and modified with stearic acid (STA)-ethanol solution to obtain STA-Ni, STA-ZnO and STA-ZnO/Ni coatings, respectively. The surface morphologies, chemical compositions and surface roughnesses of the modified coatings were characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and confocal laser scanning microscope (CLSM), respectively. The wettability tests shows that the water contact angle (WCA) of the modified coatings with micro/nanostructure are all greater than 150° and the sliding angle (SA) are all less than 10°, especially the STA-ZnO/Ni coating with a WCA of 164.3° and a SA of 2.3°, displaying the prominent superhydrophobicity. Interestingly, the three modified coatings all exhibited excellent mechanical stabilities and self-cleaning properties after being scratched by a knife blade, peeled off by adhesive tape, abrased by sandpaper, and contaminated by chalk dust. Moreover, the corrosion resistance tests confirms that the STA-ZnO/Ni superhydrophobic coating possess higher durability and anticorrosion performance than that of STA-ZnO and STA-Ni coatings. The superhydrophobic STA-ZnO/Ni composite coating prepared by two-step electrodeposition combined with low surface energy material modification designed in this work shows great potential and prospect in industrial application.