Vismara Rebecca, Terruzzi Stephanie, Maspero Angelo, Grell Toni, Bossola Filippo, Sironi Angelo, Galli Simona, Navarro Jorge A R, Colombo Valentina
Dipartimento di Scienza e Alta Tecnologia, Università degli Studi dell'Insubria, Via Valleggio 11, Como, 22100, Italy.
Departamento de Química Inorgánica, Universidad de Granada, Av. Fuentenueva S/N, Granada, 18071, Spain.
Adv Mater. 2024 Mar;36(12):e2209907. doi: 10.1002/adma.202209907. Epub 2023 Mar 14.
Understanding adsorption processes at the molecular level, with multi-technique approaches, is nowadays at the frontier of porous materials research. In this work it is shown that with a proper data treatment, in situ high-resolution powder X-ray diffraction (HR-PXRD) at variable temperature and gas pressure can reveal atomic details of the accommodation sites, the framework dynamics as well as thermodynamic information (isosteric heat of adsorption) of the CO adsorption process in the robust iron(III) pyrazolate-based MOF Fe(BDP) [HBDP = 1,4-bis(1H-pyrazol-4-yl)benzene]. Highly reliable "HR-PXRD adsorption isotherms" can be constructed from occupancy values of CO molecules. The "HR-PXRD adsorption isotherms" accurately match the results of conventional static and dynamic gas sorption experiments and Monte Carlo simulations. These results are indicative of the impact of the molecular-level behavior on the bulk properties of the system under study and of the potential of the presented multi-technique approach to understand adsorption processes in metal-organic frameworks.
如今，运用多种技术方法从分子层面理解吸附过程处于多孔材料研究的前沿。在这项工作中表明，通过适当的数据处理，可变温度和气体压力下的原位高分辨率粉末X射线衍射（HR-PXRD）能够揭示在坚固的基于吡唑铁（III）的金属有机框架Fe(BDP) [HBDP = 1,4-双(1H-吡唑-4-基)苯]中CO吸附过程的容纳位点的原子细节、框架动力学以及热力学信息（吸附等量热）。可以根据CO分子的占有率构建高度可靠的“HR-PXRD吸附等温线”。这些“HR-PXRD吸附等温线”与传统静态和动态气体吸附实验以及蒙特卡罗模拟的结果精确匹配。这些结果表明分子水平行为对所研究系统的整体性质的影响，以及所提出的多种技术方法对于理解金属有机框架中吸附过程的潜力。
