Shaping crystalline porous materials such as metal organic frameworks (MOFs) and zeolites into two-dimensional (2D) nanosheet forms is highly desirable for developing high-performance molecular sieving membranes. However, conventional exfoliation–deposition is complex and challenging for the large-scale fabrication of nanosheet MOF tubular membranes. Here, for the first time, we report a direct growth technique by ZnO self-conversion and ammonia assistance to fabricate zeolitic imidazolate framework (ZIF) membranes consisting of 2D nanosheets on porous hollow fiber substrates; the membranes are suitable for large-scale industrial gas separation processes. The proposed fabrication process for ZIF nanosheet membranes is based on the localized self-conversion of a pre-deposited thin layer of ZnO in a ligand solution containing ammonium hydroxide as a modulator. The resulting ZIF 2D nanosheet tubular membrane is highly oriented and only 50 nm in thickness. It exhibits excellent molecular sieving performance, with high H₂ permeance and selectivity for H₂/CO₂ separation. This technique shows great promise in MOF nanosheet membrane fabrication for large-scale molecular sieving applications.

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对于开发高性能分子筛膜，非常需要将诸如金属有机骨架（MOF）和沸石之类的结晶多孔材料成型为二维（2D）纳米片形式。然而，常规剥落沉积对于纳米片MOF管状膜的大规模制造是复杂且具有挑战性的。在这里，我们首次报道了通过ZnO自转化和氨辅助技术的直接生长技术，以在多孔中空纤维基材上制备由2D纳米片组成的沸石咪唑酸酯骨架（ZIF）膜。该膜适用于大规模工业气体分离工艺。ZIF纳米片膜的建议制造工艺基于预沉积的ZnO薄层在含有氢氧化铵作为调节剂的配体溶液中的局部自转化。所得的ZIF 2D纳米片管状膜是高度定向的，厚度仅为50 nm。表现出优异的分子筛性能，高H₂ H ₂ / CO ₂分离的渗透性和选择性。该技术在用于大规模分子筛应用的MOF纳米片膜的制造中显示出巨大的希望。

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