Superhydrophobic Coatings with Perfluorinated Metal-Organic Frameworks for Enhanced Corrosion Resistance

Superhydrophobic metal-organic framework (MOF)-based coatings have attracted significant attention in multifunctional surface engineering due to their tunable micro/nanoscale and chemical functionalities. In this work, fluorinated UIO-66 (UIO-66-F) nanoparticles are synthesized through molecular design and employed to construct a superhydrophobic hierarchical coating via an optimized multilayer spraying process with epoxy resin (EP). The UIO-66-F/EP coating exhibits excellent adhesion and substrate universality on various surfaces, including Q235 steel and ceramics. Moreover, the resulting coating demonstrates exceptional corrosion resistance, remarkable anti-icing capability, significant self-cleaning property, and robust mechanical strength. The molecular dynamics simulations and surface energy theory analyses reveal the synergistic protection mechanism of the MOF-based coating from molecular-scale interactions, interfacial energy modulation, and topological structure. Following a 60-day immersion in 3.5 wt.% NaCl solution, the impedance magnitude of the coating at a frequency of 0.01 Hz remains approximately seven orders of magnitude higher than that of uncoated Q235 steel. The protective mechanism is systematically elucidated from dual perspectives of low surface energy characteristics and micro/nanoscale hierarchical structure based on molecular dynamics simulations and surface energy theory analysis. The findings advance the understanding of the formation mechanisms of superhydrophobic surfaces and provide a theoretical foundation for developing novel superhydrophobic protective coatings.