Nature-Inspired Fluorine-Free Robust Superhydrophobic Fabrics

The practical implementation of superhydrophobic surfaces in oil–water separation, antifouling, and self-cleaning has been severely hampered by the incorporation of hazardous components and their limited durability. In this study, a straightforward immersion process was employed to incorporate different-sized ZnO particles onto a nonwoven substrate, resulting in the creation of a multi-layered nano-rough structure. Subsequently, polydimethylsiloxane was utilized for hydrophobic modification, aiming to decrease the free energy of the fabric surface and establish a durable covalent bond between the coating and the fabric through a cross-linking reaction during the curing process. Ultimately, the successful fabrication of superhydrophobic textiles with exceptional robustness was achieved. The prepared fabrics exhibited a static water contact angle of 163.9°. Besides, a considerable mechanical stability to withstand 80 sandpaper abrasion cycles, and chemical resistance with sustained superhydrophobic property in various harsh environments (e.g., strong acid/base solutions, and various organic solvents), were presented. Furthermore, the fabricated fabric demonstrated a separation efficiency exceeding 90% and a contact angle greater than 150° even after 50 cycles when utilized as a filter for oil–water separation. This remarkable performance can be attributed to its exceptional stain resistance and self-cleaning property.