LAUSR

Abstract In this work, a Cu Zn coating with dandelion-like CuO microstructure was fabricated on pipeline steel surface by a simple two-step combined method of electrodeposition and chemical oxidation. This coating was then coated with a thin pentadecafluorooctanoic acid to achieve superhydrophobic, with the contact angle of water about 156.81° and the sliding angle around 3°. When a water droplet contacted on the Cu Zn coating surface, the dandelion-like CuO microstructure was seen as the dual-scale structure that was proposed to be composed of spherical and pillared microstructures. Based on the Wenzel's and Cassie's formulas, the theoretical explanation was used to confirm the Cassie-Cassie wetted state between water droplet and the dandelion-like hierarchical superhydrophobic coating according to the geometric parameters of the surface morphology. Meanwhile, the superhydrophobic Cu Zn coating had the ability to repel the impinging water droplets and excellent long-term, thermal, solution immersion and chemical stability. Such robust superhydrophobic Cu Zn coating with hierarchical microstructures was expected to have various potential applications in our daily life.