福建师范大学张章静课题组在材料化学研究中取得进展。他们制备了环境条件下具有标准分离C₂H₂/CO₂选择性的接枝氢键有机框架材料。2024年10月21日，国际知名学术期刊《德国应用化学》发表了这一成果。

据介绍，利用稳健的金属配位和共价键，网状化学和孔工程在金属有机框架和共价有机框架方面取得了重大进展。然而，受到其固有的氢键弱点的阻碍，这些成果在氢键有机框架中仍然很薄弱。

在该研究中，研究团队通过接枝方法有策略地操纵了氢键框架的孔隙度，最终合成了两种具有不同孔隙环境的同构氢键有机框架(HOF)， HOF-FJU-99和HOF-FJU-100。

值得注意的是，HOF-FJU-100凭借其微孔结构，不仅表现出卓越的稳定性，而且在环境条件下对C₂H₂/CO₂混合物（50/50,v/v）实现了无与伦比的分离效率和超高选择性。它的IAST选择性值为201，作为基准，超过了以前报道的所有HOF。

单晶X射线衍射分析表明，HOF-FJU-100的孔具有非常有利于吸附C₂H₂的静电势，C₂H₂分子与骨架之间存在多重氢键相互作用。原位载气粉末的X射线衍射分析强调了孔隙结构的适应性，可以动态调整其方向以响应C₂H₂，从而通过特定的吸附相互作用，实现C₂H₂/CO₂混合物的高效和特异性分离。

附：英文原文

Title: A Grafting Hydrogen-bonded Organic Framework for Benchmark Selectivity of C2H2/CO2 Separation under Ambient Conditions

Author: Furong Yuan, Yunbin Li, Zhen Yuan, Lu Li, Chenxin Chen, Lei He, Hongyu Lin, Xi Fan, Banglin Chen, Shengchang Xiang, Zhangjing Zhang

Issue&Volume: 2024-10-21

Abstract: Reticular chemistry and pore engineering have garnered significant advancements in metal-organic frameworks and covalent organic frameworks, leveraging robust metal-coordination and covalent bonds. However, these achievements remain elusive in hydrogen-bonded organic frameworks, hindered by their inherent weakness in hydrogen bonding. Herein, we strategically manipulate the porosity of hydrogen-bonded frameworks through a grafting approach, culminating in the synthesis of two isomorphic HOFs, HOF-FJU-99 and HOF-FJU-100, with distinct pore environments. Remarkably, HOF-FJU-100, with its microporous architecture, not only showcases exceptional stability but also achieves unparalleled separation efficiency and ultrahigh selectivity for C2H2/CO2 mixtures (50/50, v/v) under ambient conditions. Its IAST selectivity value of 201 stands as a benchmark, towering over all previously reported HOFs. The pore of HOF-FJU-100 boasts an electrostatic potential highly favourable for C2H2 adsorption, as evidenced by single crystal X-ray diffraction analysis revealing multiple hydrogen bonding interactions between C2H2 molecules and the framework. In situ gas-carrier powder X-ray diffraction analysis underscores the adaptability of pore structure, dynamically adjusting its orientation in response to C2H2, thereby enabling a highly efficient and specific separation of C2H2/CO2 mixtures through specific adsorptive interactions.

DOI: 10.1002/anie.202414215

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202414215