Preparation of a robust hierarchical superhydrophobic surface with superior corrosion resistance

The design and facile fabrication of a hierarchical superhydrophobic surface with robust stability is the key for industrialization of superhydrophobic materials. Herein, a robust hierarchical superhydrophobic Zn coating (EAE-Zn) with armor-like structure was fabricated by two-step electrodeposition accompanied with an indispensable intermediate activation. The results showed that the activation treatment was favorable for the formation and growth of nano-flakes on the side surfaces of vertically aligned micro-flakes. Notably, the armor-like EAE-Zn coating still sustained its water repellency even after suffering from sandpaper abrasion, tape peeling, water drop impact and long-term immersion in salt solution, indicating that the vertically aligned micro-plates acting as "armor" could prevent effectively the abrasion of the fragile nano-structures. Besides, the superior non-wettability and impermeability endowed the EAE-Zn coating with long-term corrosion resistance ability. Therefore, these findings offer a novel strategy to design a hierarchical superhydrophobic surface with robust stability and superior corrosion resistance.