Ionic covalent organic framework (COF) nanosheets are becoming increasingly attractive as promising two‐dimensional (2D) materials for proton transport due to their ionic functionality and tailor‐made pores. However, most synthetic methods for nanosheets rely on surface‐assisted methods or phase transformation often yielding nanosheets with low aspect ratios. In this study, we present a bottom‐up approach utilizing an oil‐oil‐water triphase system to achieve the large‐scale synthesis of ionic COF nanosheets. The intermediate oil layer in this system modulates the diffusion rate of monomers from the top oil phase into the aqueous phase, enabling in‐plane anisotropic secondary growth from the initial discrete fibrous structure into large and crystalline COF nanosheets. The ionic COF nanosheets exhibit excellent proton permeability while simultaneously excluding other cations by casting into crack‐free membranes, demonstrating efficient HCl extraction from acidic water waste. This strategy for larger‐scale COF nanosheet growth will offer an alternative platform for designing multifunctional COF membranes with applications in sophisticated separation technologies.

中文翻译：

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通过组装的阳离子共价有机框架纳米片实现超高质子选择性


离子共价有机框架 （COF） 纳米片由于其离子功能和量身定制的孔隙，作为用于质子传输的二维 （2D） 材料越来越有前途。然而，纳米片的大多数合成方法依赖于表面辅助方法或相变，通常产生具有低纵横比的纳米片。在这项研究中，我们提出了一种自下而上的方法，利用油-油-水三相系统来实现离子 COF 纳米片的大规模合成。该系统中的中间油层调节单体从顶部油相到水相的扩散速率，从而实现从初始离散纤维结构到大而结晶的 COF 纳米片的面内各向异性二次生长。离子 COF 纳米片表现出优异的质子渗透性，同时通过铸造到无裂纹膜中排除其他阳离子，展示了从酸性水废物中高效提取 HCl。这种更大规模的 COF 纳米片生长策略将为设计多功能 COF 膜提供一个替代平台，并应用于复杂的分离技术。