Poly(triazine imide) (PTI), a crystalline g-C3N4, hosting two-dimensional nanoporous structure with an electron density gap of 0.34 nm, is highly promising for high-temperature hydrogen sieving because of its high chemical and thermal robustness. Currently, layered PTI is synthesized in potentially unsafe vacuum ampules in milligram quantities. Here, we demonstrate a scalable and safe ambient pressure synthesis route leading to several grams of layered PTI platelets in a single batch with 70% yield with respect to the precursor. Solvent exfoliation under anhydrous conditions led to single-layer PTI nanosheets evidenced by the observation of triangular g-C3N4 nanopores. Gas permeation studies confirm that PTI nanopores can sieve He and H2 from larger molecules. Last, high-temperature H2 sieving from PTI nanosheet-based membranes, prepared by the scalable filter coating technique, is demonstrated with H2 permeance reaching 1500 gas permeation units, with H2/CO2, H2/N2, and H2/CH4 selectivities reaching 10, 50, and 60, respectively, at 250°C.

中文翻译：

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晶体g-C3N4纳米片的大规模合成和组装膜的高温H2筛分。

聚（三嗪酰亚胺）（PTI）是一种结晶g-C3N4，具有二维纳米多孔结构，电子密度间隙为0.34 nm，由于其高化学稳定性和热稳定性，因此非常有希望用于高温氢筛。目前，分层的PTI是以毫克量潜在地不安全的真空安瓿瓶合成的。在这里，我们展示了一种可扩展且安全的环境压力合成路线，可在一批次中产生几克分层的PTI血小板，相对于前体，其收率为70％。无水条件下的溶剂剥离导致单层PTI纳米片的出现，这是通过观察三角形g-C3N4纳米孔而证明的。气体渗透研究证实，PTI纳米孔可从较大分子中筛出He和H2。最后，从基于PTI纳米片的膜中进行高温H2筛分，