Bioinspired super-hydrophobic fractal array via a facile electrochemical route: preparation and corrosion inhibition for Cu

Abstract

Super-hydrophobic surfaces (SHS) usually are formed from a combination of low surface energy materials and micro/nanostructures via two-step approaches, and they have promising applications in material corrosion protection. In this paper, the authors obtained a super-hydrophobic surface onto the copper plates through a rapid one-step electrodeposition process from the electrolytic solution containing cobalt nitrate (Co(NO₃)₂·6H₂O), myristic acid, and ethanol. The electrochemical impedance spectroscopy and polarization curve are adopted to evaluate a super-hydrophobic surface's durability and corrosion resistance. The results demonstrate that the super-hydrophobic cobalt myristate coating showed excellent corrosion inhibition in simulated seawater solution with a corrosion inhibition efficiency as high as 98.82%. Furthermore, the super-hydrophobic layer could be considered a barrier and thus require an ideal air-liquid interface that inhibits the diffusion of the corrosive species. The construction of super-hydrophobic characters with a self-cleaning property is significant and used widely, attracting numerous studies for obtaining surfaces with low surface energy and micro/nanostructures. The as-fabricated super-hydrophobic surfaces possess the external surface adhesive force to the water phase and excellent self-cleaning and antifouling ability. By adjusting processing time, the water contact angle of the coated copper surface reaches 152.9°, showing a superb superhydrophobicity. The morphology, chemical composition, and wettability characterization were analyzed using scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and contact angle measurements. In addition, a scanning Kelvin probe (SKP) usage in this work is to measure the atmospheric corrosion behavior of copper with the super-hydrophobic coating. Thus, this proposed method provides a simple way to rapidly equip super-hydrophobic coating onto the metal surface to realize corrosion inhibition.