Nano-structure and hydrophobicity co-determined barrier properties of corrosion protective ZnAl-LDH film in atmospheric environment

• Published in: Corrosion science 2024-05, Vol.232, p.112052, Article 112052
• Main Authors: Zhang, Han, Sun, Wen, Wang, Lida, Feng, Yixuan, Ma, Shiheng, Zhao, Liqiu, Liu, Guichang
• Format: Article
• Language: English
• Subjects: Barrier properties; Corrosion protection; Hydrophobic stability; Nano-structure; Superhydrophobic coating
• ISSN: 0010-938X; 1879-0496
• DOI: 10.1016/j.corsci.2024.112052

Salt spray is prone to convert superhydrophobic surface from Cassie-Baxter state to Wenzel state, which accelerates the metallic corrosion. Herein, corrosion process of superhydrophobic coatings were investigated by in-situ growth of LDH lamellae with different platelet spacing and modification of stearic acid. The corrosion protection mechanism of the superhydrophobic coating divided into two stages: the well-known air film blocking effect and the hydrophobicity-depended barrier performance, which is a new focus. Through investigating the influences of the nano-structure on corrosion protection via experiments and simulation, a new mechanism on corrosion protection failure of superhydrophobic surfaces in atmospheric environment is proposed. •Superhydrophobic ZnAl-LDH surfaces with different nano-structures were prepared.•Nano-structures and hydrophobicity jointly determined barrier properties.•The advantages of the coating to prevent marine atmospheric corrosion were proven.•A new mechanism on barrier failure of superhydrophobic surface was proposed.