Metal-organic framework based molecularly imprinted nanofiber membranes with enhanced selective recognition and separation performance: A multiple strengthening system

Metal-organic frameworks (MOFs) are promising candidates to functionalized polymer membrane, its three dimensional porous network and large surface also provide inspiration for the construction of novel molecularly imprinted membranes (MIMs). In this study, a multiple strengthening strategy was proposed for the preparation of MOFs based molecularly imprinted nanofiber membranes (MINMs): (i) Polydopamine (PDA) modified PVDF nanofiber membranes (PVDF/PDA) as basal membrane was developed by in-situ self-polymerization method, which has improved the hydrophilicity and antifouling performance. (ii) ZIF-8 nanocrystals were assembled onto the surface of PVDF/PDA nanofibers membrane that not only increases the surface area of the nanofiber membrane to facilitate attachment of more imprinting sites, but also acts as a structure-directing functional monomer to further strengthen the specific recognition ability by synergistic effect. As a result, the MINMs achieves a desired adsorption capacity (31.32 mg g−1) and permselectivity (permselectivity factors β were 3.29, 3.39 and 3.51) towards template molecules. Importantly, the as-designed MINMs also displays strong practicability in simulated real sample. The presented MINMs fabrication strategy has shown tremendous potential for using MOFs to design MIMs with enhanced the selective separation performance.