A bionic micro-nano structure fluorine-free superhydrophobic mesh with excellent mechanical/chemical stability for oil/water separation and fog collection

Due to the growing issues of environmental pollution and resource shortages, the fluorine-free superhydrophobic membrane prepared by electrodeposition presents a practical solution, offering environmental friendliness, high stability, and ease of fabrication. However, the above fluorine-free superhydrophobic functional materials are still limited by insufficient performance to access competent oil/water separation and fog collection. Here, a non-fluorinated multifunctional biomimetic superhydrophobic copper mesh (NC-BS) is fabricated by combining wire electrical discharge machining (WEDM) with pulsed electrochemical deposition. The bionic surface achieves excellent superhydrophobic properties by simultaneously simulating the microstructure of the gecko skin surface and the nano-mastoid on the surface of the lotus leaf with special wettability. In this study, the synergistic effect of hierarchical bionic micro/nanostructures and a nickel myristate/chromium myristate mixture, which results in a low-adhesion surface, demonstrates significant advantages in self-cleaning and antifouling properties. The NC-BS surface also shows remarkable mechanical and chemical stability, maintaining hydrophobicity over an extended period. In application tests, NC-BS manifests excellent separation of oil/water mixed solution and fog collection capabilities. The n-hexane/water mixture has a separation efficiency of up to 98.1%, a separation flux of around 104,300 L·m −2 ·h −1 , and a fog collecting efficiency of around 3040 mg·cm −2 ·h −1 . Moreover, the bionic composite structure significantly enhances pressure resistance, thereby achieving stable and high flux oil/water separation. This study presents an innovative solution to address the technical bottleneck of deficient wettability and poor durability in fluorine-free superhydrophobic functional materials, laying a crucial foundation for their practical application in environmental governance and resource recovery.