Flexible chromium‐based metal‐organic frameworks (MOFs) possess unique structural properties on account of their intriguing breathing effect. However, their synthesis often requires the use of corrosive HF and bulk solvents. Herein, we report a facile 2‐step synthesis of flexible MIL‐53 (Cr) and MIL‐88B (Cr) without using solvents and HF acid modulator. This methodology was highly selective based on the type of metal precursors used, giving the two MOFs separately under similar synthetic procedure. The synthesized MIL‐53 (Cr) and MIL‐88B (Cr) were fully characterized by multiple techniques to ensure their high quality. This work highlights a useful strategy to be adopted for future scale‐up production of flexible chromium‐based MOFs.

中文翻译：

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柔性基于铬的MIL-53和MIL-88B的无溶剂和无HF合成

柔性铬基金属有机骨架（MOF）具有独特的结构特性，因为它们具有吸引人的呼吸效果。但是，它们的合成通常需要使用腐蚀性的HF和本体溶剂。本文中，我们报告了一种不需使用溶剂和HF酸调节剂即可轻松完成柔性MIL-53（Cr）和MIL-88B（Cr）的两步合成的过程。根据所用金属前体的类型，该方法具有高度选择性，可以在相似的合成步骤下分别得到两个MOF。合成的MIL-53（Cr）和MIL-88B（Cr）具有多种技术来充分表征，以确保其高质量。这项工作着重指出了将来在柔性铬基MOF的大规模生产中将采用的有用策略。