Recently, Professor Liu Xinlei at the School of Chemical Engineering and Technology published a communication entitled “Highly Water-Permeable Metal–Organic Framework MOF-303 Membranes for Desalination” in Journal of the American Chemical Society (https://doi.org/10.1021/jacs.1c10192). PhD candidate Cong Shenzhen was the first author.

Metal−organic frameworks (MOFs) are a family of porous crystalline materials composed of inorganic metal ions or metal clusters connected by organic ligands via coordination bonds. Because of their diversity in chemistry and topology, MOFs have been extensively explored for applications. However, applications of polycrystalline MOF membranes in water treatment were initially obstructed because of the lack of chemical stability. Although highly water-stable zirconium MOF membranes were unveiled in recent years, the related research is still in its infancy. Highly water-permeable MOF membranes with satisfying rejection had been in demand.

In this work, the authors prepared a continuous, defect-free MOF-303 membrane on the α-Al₂O₃substrates via an in situ hydrothermal synthesis method. The membranes exhibit satisfying rejection of divalent ions (e.g., 93.5% for MgCl₂and 96.0% for Na₂SO₄) on the basis of a size-sieving and electrostatic-repulsion mechanism and unprecedented permeability (3.0 L·m^-2·h^-1·bar⁻¹·μm). The high water capacity and fast water sorption kinetics of MOF-303 played an important role in this exceptional water permeability. The water permeability outperforms typical zirconium MOF, zeolite, and commercial polymeric reverse osmosis and nanofiltration membranes. Besides, the membranes have good chemical stability and low production costs. These merits recommend MOF-303 as a next-generation membrane material for water softening.

Dr. Xinlei Liu is a professor at the School of Chemical Engineering and Technology at Tianjin University. He is interested in membranes, adsorbents and porous framework chemistry. His research details can be found at the website:http://chemeng.tju.edu.cn/cn/szdw?type=detail&subtype=13&id=512

By：The School of Chemical Engineering and Technology

Editors: Qin Mian & Yang Fan