Abstract Co-deposition between plant polyphenol tannic acid (TA) and Fe3+ has been reported to be a facile way to construct nanofiltration (NF) membranes. However, this strategy suffers the problems of low atom economy and generating a large amount of environment-harmful aggregate wastes in solution. This work proposed a novel method based on layer-by-layer (LBL) self-assembly for preparation of TA-Fe3+ complex based NF membrane. The proposed method was facile and environmental-friendly because it did not require any chemical or solvent involved pretreatment nor generated any aggregate waste. A series of characterizations proved the successful formation of TA-Fe3+ complex based top layer on polyacrylonitrile (PAN) support surface. The resultant membrane showed superhydrophilicity property with water contact angle as low as 8°. Meanwhile, the optimized membrane showed a high water permeance of 40.9 L m−2 h−1 bar−1 whilst simultaneously maintained rejections higher than 93.9% towards various dyes with the molecular weight (MW) ranging from 320 to 1017 Da. Moreover, the as-prepared NF membranes showed stable long-term separation performance and good ion/organic selective separation performance. This study not only proposed a facile fabrication process for TA-Fe3+ complex based NF membrane, but also provided great potentials for sustainable molecular separation by the prepared membranes.

中文翻译：

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通过单宁酸和铁的逐层自组装轻松制造超亲水纳滤膜用于染料分离

摘要 据报道，植物多酚单宁酸 (TA) 和 Fe3+ 之间的共沉积是构建纳滤 (NF) 膜的简便方法。然而，该策略存在原子经济性低和在溶液中产生大量对环境有害的聚集废物的问题。这项工作提出了一种基于逐层（LBL）自组装的新方法，用于制备基于 TA-Fe3+ 复合物的 NF 膜。所提出的方法简便且环保，因为它不需要任何涉及预处理的化学品或溶剂，也不会产生任何聚集废物。一系列表征证明在聚丙烯腈 (PAN) 支撑表面上成功形成了基于 TA-Fe3+ 复合物的顶层。所得膜显示出超亲水性，水接触角低至 8°。同时，优化后的膜显示出 40.9 L m-2 h-1 bar-1 的高透水性，同时对分子量 (MW) 范围为 320 至 1017 Da 的各种染料保持高于 93.9% 的截留率。此外，所制备的NF膜表现出稳定的长期分离性能和良好的离子/有机选择性分离性能。该研究不仅提出了一种基于 TA-Fe3+ 络合物的 NF 膜的简便制备工艺，而且为制备的膜进行可持续的分子分离提供了巨大的潜力。所制备的纳滤膜表现出稳定的长期分离性能和良好的离子/有机选择性分离性能。该研究不仅提出了一种基于 TA-Fe3+ 络合物的 NF 膜的简便制备工艺，而且为制备的膜进行可持续的分子分离提供了巨大的潜力。所制备的纳滤膜表现出稳定的长期分离性能和良好的离子/有机选择性分离性能。该研究不仅提出了一种基于 TA-Fe3+ 络合物的 NF 膜的简便制备工艺，而且为制备的膜进行可持续的分子分离提供了巨大的潜力。