Facile preparation of superhydrophobic metal meshes with micro-hierarchical structure via in situ self-assembly metal-organic framework for efficient oil-water separation

Superhydrophobic materials with micro-hierarchical structure are widely in oil-water separation. However, the environmental suitability and stability of material are still a challenge. To overcome this problem, a novel superhydrophobic Cu-MOF based copper mesh was prepared by first using chemical oxidation to obtain Cu(OH)2 nanoarrays on copper substrate, then metal-organic framework (Cu-MOF) crystals were in situ grown using Cu(OH)2 as a sacrificial template, and follow treated with methylpolysiloxane (PDMS). The wetting behavior, surface morphology and physical structure of the modified copper mesh were characterized by the SEM, XRD, FTIR, XPS and WCAs test. The results show that the assembled nanoarrays and deposited crystal particle exhibit a more stable three-dimensional rough structure, which adapted to the harsh oil-water separation environment. The obtained superhydrophobic modified copper mesh (WCA = 156.2°) has a high separation efficiency (96%–99%) and oil flux (2.1–7.3 L m−1 s−1) for different types of oil-water mixtures, and good repeatability. Based on in situ growth strategy and gentle preparation process, the as-prepared functional copper mesh with a low-cost and high-performance has great potential in oil-spill repairment and efficient separation of organic liquids.