Thin-film composite membrane for desalination containing a sulfonated UiO-66 material.

Desalination through reverse osmosis (RO) membrane is one of the most popular ways. However, conventional RO membranes meet a trade-off between salt rejection and water flux which limit their comprehensive performance. In this work, sulfonated zirconium (IV)-carboxylate metal–organic framework (MOF) material UiO-66-SO3H was successfully synthesized, and thin-film nanocomposite (TFN) with UiO-66-SO3H-incorporated polyamide (PA) layer was fabricated. Angstrom-sized UiO-66-X ion transport channels with different functional groups in TFN membranes change the membrane morphology and chemistry and accelerate the penetration of water molecules while maintaining the high ion screening effect. As a result, compared to the pristine TFC membrane, the optimized TFN-UiO-66-SO3H membrane exhibited an increase in water molecules permeability to 347% and still maintained a salt rejection with ~ 94.7% under 2000 ppm NaCl solution with reverse osmosis (RO) mode, leading to a great improvement of intrinsic separation properties. The improved performance was owing to the size exclusion effect and hydrophilic nature of UiO-66-SO3H particles. What is more, the additional water migration channels through the incorporated UiO-66-SO3H nanoparticles lead to a boosting water permeation and show optimized performance for desalination. [ABSTRACT FROM AUTHOR]