Nanofiltration membranes show great potential in water treatment and resource recovery for their special separation mechanisms that can separate the small molecules effectively. However, their wide application needs to address the low separation efficiency caused by the similar solute sizes and charges while using the charged NF membranes with nanopores. This work reports a low-cost amine–carbon quantum dots (CQDs–NH₂) modified thin-film composite (CTFC) membrane via the facile interfacial polymerization process. The electrostatic force and competing reaction between the positively charged CQDs–NH₂ and the reactive monomers reformulated the interfacial polymerization process. The resultant CTFC membrane exhibits improved surface morphology and hydrophilicity. Besides, the incorporation of CQDs–NH₂ changed the original polyamide network structures to construct more transport space. The CTFC membrane permeance was boosted significantly (from 6.2 to 38.44 L m⁻² h⁻¹ bar⁻¹) compared with the unmodified TFC membrane, showing precise dyes separation property. This work may offer valuable guidance for the low-cost loose nanofiltration membrane preparation towards molecular separation.

纳滤膜具有特殊的分离机制，可以有效地分离小分子，因此在水处理和资源回收方面显示出巨大的潜力。然而，它们的广泛应用需要解决在将带电荷的NF膜与纳米孔一起使用时，由相似的溶质尺寸和电荷引起的低分离效率。这项工作报告了一种通过简便的界面聚合过程制备的低成本胺-碳量子点（CQDs-NH ₂）改性薄膜复合材料（CTFC）膜。带正电的CQDs–NH ₂之间的静电力和竞争反应反应性单体重新定义了界面聚合过程。所得的CTFC膜表现出改善的表面形态和亲水性。此外，CQDs-NH ₂的引入改变了原来的聚酰胺网络结构，从而构建了更多的运输空间。与未改性的TFC膜相比，CTFC膜的渗透性显着提高（从6.2升至38.44 L m ^-2 h ^-1 bar ^-1），显示出精确的染料分离性能。这项工作可能为低成本的松散纳滤膜制备分子分离提供有价值的指导。