UiO-66 and UiO-66-NH2 membranes-based superhydrophobic coatings for enhanced corrosion protection

Fabricating metal-organic frameworks (MOFs) membranes directly onto metal surfaces as anticorrosive coatings is a feasible approach for the application of MOFs in corrosion protection . The MOFs membranes with specific organic groups can be further customized as versatile platforms for developing various functional coatings. Herein, UiO-66 and UiO-66-NH 2 membranes are synthesized onto aluminum surfaces through a polydopamine-assisted method, which are then grafted with superhydrophobic molecules of perfluorodecyltriethoxysilane (PFDTES). The -COOH groups in UiO-66 and -COOH/-NH 2 groups in UiO-66-NH 2 can serve as firm anchor sites for covalently grafting with PFDTES, enabling robust superhydrophobicity of the as-prepared coatings. The superhydrophobic surfaces exhibit water repellency (water contact angle of ∼165 o ), chemical (pH and salinity) and wear-resisting robustness, and long-term service durability. They also perform decent anti-fouling, self-cleaning, and anti-icing properties. Notably, sustainable corrosion protection can be provided by both coatings during immersion in saline solution (3.5 wt% NaCl) for one month and during a two-week salt spray test. Compared with UiO-66, the -NH 2 groups on UiO-66-NH 2 as extra grafting sites for firmer immobilization of more PFDTES molecules facilitate more durable superhydrophobicity and corrosion protection. We believe that this work could offer valuable insights into the multi-functional development of MOFs membranes-based coatings.