Membrane-based separation is one of the most energy-efficient methods to meet the growing need for a significant amount of fresh water. It is also well-known for its applications in water treatment, desalination, solvent recycling, and environmental remediation. Most typical membranes used for separation-based applications are thin-film composite membranes created using polymers, featuring a top selective layer generated by employing the interfacial polymerization technique at an aqueous–organic interface. In the last decade, various manufacturing techniques have been developed in order to create high-specification membranes. Among them, the creation of ultrathin polyamide membranes has shown enormous potential for achieving a significant increase in the water permeation rate, translating into major energy savings in various applications. However, this great potential of ultrathin membranes is greatly hindered by undesired transport phenomena such as the geometry-induced “funnel effect” arising from the substrate membrane, severely limiting the actual permeation rate. As a result, the separation capability of ultrathin membranes is still not fully unleashed or understood, and a critical assessment of their limitations and potential solutions for future studies is still lacking. Here, we provide a summary of the latest developments in the design of ultrathin polyamide membranes, which have been achieved by controlling the interfacial polymerization process and utilizing a number of novel manufacturing processes for ionic and molecular separations. Next, an overview of the in-depth assessment of their limitations resulting from the substrate membrane, along with potential solutions and future perspectives will be covered in this review.

中文翻译：

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在水-能源关系中增强超薄聚酰胺膜：策略、局限性和未来前景

膜分离是满足日益增长的大量淡水需求的最节能的方法之一。它还因其在水处理、海水淡化、溶剂回收和环境修复方面的应用而闻名。用于基于分离的应用的最典型的膜是使用聚合物创建的薄膜复合膜，具有通过在水-有机界面处采用界面聚合技术生成的顶部选择性层。在过去的十年中，已经开发了各种制造技术来制造高规格的膜。其中，超薄聚酰胺膜的制造已显示出实现水渗透率显着提高的巨大潜力，从而在各种应用中转化为重大节能效果。然而，超薄膜的巨大潜力受到了不良传输现象的极大阻碍，例如基底膜产生的几何诱导的“漏斗效应”，严重限制了实际的渗透速率。因此，超薄膜的分离能力仍未完全释放或被理解，并且仍然缺乏对其局限性和未来研究的潜在解决方案的严格评估。在这里，我们总结了超薄聚酰胺膜设计的最新进展，这些进展是通过控制界面聚合过程并利用许多用于离子和分子分离的新颖制造工艺来实现的。接下来，本次综述将概述对基底膜造成的局限性的深入评估，以及潜在的解决方案和未来的前景。