Facile fabrication of robust superhydrophobic coating for enhanced corrosion protection on AZ91 magnesium alloy by electroless Ni-B/GO plating

Authors：Zhang, Yongjun^*; Shen, Xianlong

Source：Surface and Coatings Technology, 2023, 455: 129213.

DOI：10.1016/j.surfcoat.2022.129213

• Superhydrophobicity
• Magnesium alloy
• Graphene oxide
• Electroless plating
• Ni-B
• Corrosion protection

Artificial superhydrophobic surfaces have drawn extensive research interest due to their great applicational potential. However, the specialized materials and equipment, multistep preparation processes, and vulnerable rough structures severely restrict their industrial development. In this research, a robust superhydrophobic Ni-B/ GO composite coating was fabricated successfully on AZ91 magnesium alloy based on electroless plating (EP), followed by chemical modification with stearic acid ethanol solution. With a water contact angle of 162.8 degrees and a sliding angle of 1.3 degrees, the superhydrophobic coating displayed strong physical/chemical stability and outstanding self-cleaning. Moreover, the superhydrophobic coating revealed excellent corrosion resistance with higher E-corr (-0.411 V) and lower i(corr) (2.14 x 10(-6) A center dot cm(-2)) in 3.5 wt% NaCl solution. Also, the R-ct value was 2.75 x 10(5) Omega center dot cm(2) and increased three orders of magnitude compared with the AZ91 Mg. Therefore, this study offers an innovative perspective for fabricating the micro/nano rough structures on magnesium alloy, and the fabrication of superhydrophobic coatings by electroless nickel plating as a low-cost and eco-friendly method will have good industrial application prospects.