Ultrahigh-flux 1D metal–organic framework nanowires membranes for selective dye separation

Low-dimensional metal–organic frameworks (MOFs) have attracted substantial research interest in the field of water treatment. However, the simultaneous realization of ultra-high flux and precise molecular sieving remains a critical challenge. Herein, we report a novel one-dimensional (1D) Ni-MOF nanowires via a solvothermal method. By systematically tuning the reaction temperature, Ni-MOF nanostructures with distinct dimensionalities − including nanosheets (NSs), nanoneedles (NNs), and nanowires (NWs) were successfully prepared. Notably, the Ni-MOF NWs exhibited an exceptional adsorption capacity of 567 mg·g −1 for Brilliant Blue (B.B.), while demonstrating negligible adsorption towards Acid Red 18 (A.R.18). This selective adsorption was attributed to preferential hydrogen bonding and π–π interactions. Benefiting from their high specific surface area and hierarchical porosity, the Ni-MOF NWs were deposited onto cellulose acetate substrates to fabricate membranes with tunable thickness. The optimized 3.0 μm-thick membrane achieved a superior water permeance of 250 LMH·bar −1 and nearly complete (∼ 100 %) rejection of B.B., while allowing A.R.18 to pass through unimpeded. The results of molecular simulation showed that the stacked nanochannels by 1D Ni-MOF NWs   and the strong coordination effect within the Ni-MOF NWs membrane enhanced the dyes separation effect and rejection. Moreover, the membrane maintained 100 % B.B. removal efficiency over 10 regeneration cycles and exhibited an effective antifouling ability, underscoring its outstanding operational stability and recyclability. This work not only introduces a scalable strategy for constructing low-dimensional MOF-based membranes but also offers a promising solution for energy-efficient, high-throughput treatment of dye-containing wastewater.