ZIF-8 nanowire regulated thin-film nanocomposite membrane for improved desalination performance

The development of polyamide nanofiltration membrane is hindered by its low permeability. Rationally designing thin film nanocomposite (TFN) membranes through adding filler to polyamide layer is a promising method for improved nanofiltration performance. However, regulating the morphology and polymerization process of polyamide layer through the design of filler morphology is challenging. In this work, we designed a ZIF-8 nanowire regulated TFN membrane. Different from the reported nanomaterials, the irregular surface of ZIF-8 nanowire is conducive to forming crumpled membrane surface by controlling the interfacial polymerization process. Meanwhile, ZIF-8 nanowire can construct net-like channels in polyamide matrix for improved water permeability. The influence of ZIF-8 nanowire on morphology, chemical property, and desalination performance of TFN membrane were studied. As a result, the optimized TFN-Z2 membrane with ZIF-8 nanowire loading of 0.10 w/v% shows a flux of 6.42 LMH bar −1 , which increased by 189 % than that of the polyamide membrane. Meanwhile, the TFN-Z2 membrane maintained excellent rejection performance for salts (93.60 %, 91.20 %, 91.20 %, and 78.60 % for Na 2 SO 4 , MgSO 4 , MgCl 4 , and NaCl, respectively). The results can provide a foundation for the preparation of more advanced membranes.