Engineering superhydrophobic surfaces with metal-organic frameworks (MOFs): Design principles, fabrication, and...

Metal-organic frameworks (MOFs) provide a tunable platform for constructing hydrophobic and superhydrophobic surfaces because their metal nodes, organic linkers, pore architectures, and external crystal morphologies can be regulated across multiple length scales. This review analyzes MOF-based superhydrophobic surfaces from the perspectives of design principles, fabrication strategies, interfacial wetting mechanisms, and multifunctional applications. Rather than treating MOFs only as porous powders or general functional additives, the review focuses on how molecular-level MOF characteristics can relate to macroscopic surface properties. Based on biomimetic principles and classical wetting theories, particular attention is given to the synergistic role of micro/nanoscale hierarchical roughness and controlled surface energy in stabilizing Cassie-Baxter wetting states. MOF-related interfacial phenomena, including capillary effects, contact-line pinning, nanoconfinement, and stimuli-responsive wetting transitions, are discussed in relation to surface wettability and droplet mobility. Wettability regulation strategies are organized into intrinsic hydrophobic ligand design, post-synthetic modification, hydrophobic MOF powder utilization, and MOF-polymer composite fabrication. The review also compares top-down and bottom-up fabrication approaches, with emphasis on scalability, durability, sustainability, and practical processing constraints. Furthermore, representative applications, including oil-water separation, self-cleaning, anti-/de-icing, anti-corrosion, antibacterial surfaces, photocatalysis, fog harvesting, and fluid transport, are discussed with attention to key performance indicators and current limitations. Finally, remaining challenges related to structural stability, mechanical durability, scalable manufacturing, environmental compatibility, and dynamic wettability regulation are summarized, and future opportunities in AI-assisted design, sustainable synthesis, quantitative benchmarking, and multifunctional interface engineering are outlined.