Incorporating hydrophilic and charged porous nanofillers to prepare high-performance thin film nanocomposite (TFN) nanofiltration (NF) membranes is an effective method to achieve efficient water treatment. In this study, we synthesize the sulfonated covalent organic framework nanosheets (S-CONs) with higher hydrophilicity and electronegativity by immobilizing sulfonic acid groups (–SO₃H) on TpPa-1 nanosheets. The S-CONs are incorporated in the PA layer by interfacial polymerization (IP) reaction. The results indicated that the S-CONs could modulate the hydrophilicity, thickness, and electronegativity of TFN-NF membranes. At the optimal addition of S-CONs (0.006 g), the pure water permeance increases to 8.84 \({\rm{L}}\cdot{\rm{m}}^{-2}\cdot{\rm{h}}^{-1}\cdot{\rm{bar}}^{-1}\), which is about 1.75 times than the TFC membrane, with a high Na₂SO₄ rejection reaching 98.97%. The improvement of the separation performance mainly results from the reduction of PA layer thickness (from ~178.00–198.00 to ~100.00–128.00 nm) and the increase of surface electronegativity (from −20.37 to −44.41 mV at pH = 7.00). More interestingly, the amide bond formed between the S-CONs and TMC improved the chlorine resistance of the membranes. This study reveals the potential of using functionalized 2D CONs as nanofillers to modify TFC membranes for efficient nanofiltration.

结合亲水性和带电多孔纳米填料制备高性能薄膜纳米复合（TFN）纳滤（NF）膜是实现高效水处理的有效方法。在本研究中，我们通过将磺酸基团（–SO ₃ H）固定在TpPa-1纳米片上，合成了具有更高亲水性和电负性的磺化共价有机骨架纳米片（S-CON）。 S-CON 通过界面聚合 (IP) 反应融入 PA 层中。结果表明，S-CON 可以调节 TFN-NF 膜的亲水性、厚度和电负性。在最佳 S-CON 添加量 (0.006 g) 下，纯水渗透率增加至 8.84  \({\rm{L}}\cdot{\rm{m}}^{-2}\cdot{\rm{h }}^{-1}\cdot{\rm{bar}}^{-1}\)，约为TFC膜的1.75倍，Na ₂ SO ₄截留率高达98.97%。分离性能的改善主要归因于PA层厚度的减小（从~178.00–198.00到~100.00–128.00 nm）和表面电负性的增加（pH = 7.00时从-20.37到-44.41 mV）。更有趣的是，S-CON 和 TMC 之间形成的酰胺键提高了膜的耐氯性。这项研究揭示了使用功能化 2D CON 作为纳米填料来修饰 TFC 膜以实现高效纳滤的潜力。