Eco-Friendly Anticorrosion Superhydrophobic Al2O3@PDMS Coating With Salt Deliquescence Self-Coalescence Behaviors Under High Atmospheric Humidity

• Published in: Frontiers in materials Vol. 9
• Main Authors: Zhang, Binbin, Yan, Jiayang, Xu, Weichen, Yu, Teng, Chen, Zhuoyuan, Duan, Jizhou
• Format: Journal Article
• Language: English
• Published: Frontiers Media S.A 26.01.2022
• Subjects: anticorrosion; atmospheric corrosion; fluorine-free; salt deliquescence; superhydrophobic
• ISSN: 2296-8016; 2296-8016
• DOI: 10.3389/fmats.2022.839948

Bio-inspired superhydrophobic coatings have been demonstrated to be promising anticorrosion materials. However, developing robust superhydrophobic coatings through simple one-step fluorine-free procedures to meet various functional requirements remains a major challenge. In this study, we fabricated an eco-friendly superhydrophobic Al 2 O 3 @PDMS composite coating with mechanical robustness based on Al 2 O 3 NPs, PDMS, and spray coating technique. To characterize surface morphologies, chemical compositions, surface wettability, and anticorrosion properties, FE-SEM, EDS, XPS, contact angle meter, electrochemical impendence spectroscopy, and potentiodynamic polarization techniques were employed. The electrochemical results show that |Z| 0.01 Hz and R ct values of the superhydrophobic Al 2 O 3 @PDMS coating were four orders of magnitude higher than bare Q235 carbon steel, indicating a significant improvement in corrosion resistance. Furthermore, the deliquescence behaviors of NaCl salt particles and the instantaneous self-coalescence phenomenon were recorded under high atmospheric humidity to suggest that a superhydrophobic surface with Cassie–Baxter interfacial contacts can serve as an efficient barrier to suppress the formation of saline liquid thin films and protect the underlying substrate from corrosion. This robust superhydrophobic Al 2 O 3 @PDMS coating is expected to be easily applied to a variety of substrates and to find potential applications for liquid repellency, self-cleaning, corrosion resistance, and other properties.