Underwater superoleophobic fabric based on UiO-66-COOH for high flux oil-water separation

As the pollution of oily wastewater becomes more and more serious, it has a great negative impact on the ecosystem and human health. How to achieve efficient oil-water separation has become a common ecological problem all over the world. Therefore, it is extremely significant to develop innovative and efficient oil-water separation membranes. Past studies have shown that the metal-organic framework material UiO-66 (Zr), which has free carboxyl groups, is not only hydrophilic but also has good stability. Inspired by this, an ingenious method for a polydopamine (PDA) and metal-organic skeleton UiO-66(Zr) coating anchoring on cotton fabric surface was proposed, and the final product was denoted as CF-PDA@CS@UiO-66-COOH fabrics. Particularly noteworthy is that the separation efficiency of CF-PDA@CS@UiO-66-COOH for various organics exceeded 99.83 %, the water flux was achieved to 100744.5 L/(m 2 ·h). After 20 cycles, the separation efficiency exceeded 99.81 % and the water flux always surpassed 75067.9 L/(m 2 ·h). In addition, the prepared membranes were able to maintain excellent underwater superoleophobic properties even under acidic or alkaline environmental conditions or after 50 sandpaper abrasion cycles. And it also has excellent self-cleaning and anti-fouling. These excellent properties are due to the strong anchoring between CF, PDA, CS and UiO-66-COOH. This facile and scalable functional fabric could be applied to a wide range of oil-water separation and facilitate the development of high flux separation devices.