Few-layers 2D O-MoS2 TFN nanofiltration membranes for future desalination

Advanced membranes with high water flux, excellent salt selectivity as well as superior fouling resistance are highly demanded in water desalination and water treatment. Herein, a new nanocomposite nanofiltration (NF) membrane was reported by introducing the two-dimensional (2D) oxidized molybdenum disulfide (O-MoS2) into the polyamide selective layer. O-MoS2 with high hydrophilicity and strong electronegativity was synthesized by the oxidation and exfoliation process. The nanocomposite membrane was successfully prepared through interfacial polymerization with the incorporation of O-MoS2 into organic phase. O-MoS2 was successfully embedded in the membranes as visualized by SEM and TEM characterizations. The hydrophilicity and electronegativity of the nanocomposite membranes were improved. Compared with the pristine membrane, the performance of the membrane was best when the concentration of O-MoS2 was 0.010 wt/v%. Consequently, the Na2SO4 rejection increased to 97.9%, and the water flux was 2.5 times higher. In addition, the membrane displayed excellent antifouling properties. The results showed that O-MoS2 as an excellent 2D modifier would bring more breakthrough improvements in the field of membrane separation.