Cho Hae Sung, Tanaka Hideki, Lee Yongjin, Zhang Yue-Biao, Jiang Juncong, Kim Minho, Kim Hyungjun, Kang Jeung Ku, Terasaki Osamu
School of Physical Science and Technology, ShanghaiTech University, Shanghai, 201210, China.
Graduate School of EEWS, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 34141, Republic of Korea.
Angew Chem Int Ed Engl. 2021 Sep 6;60(37):20504-20510. doi: 10.1002/anie.202107897. Epub 2021 Jul 26.
For a better design of adsorbents, it is important to know the intermolecular interaction among adsorbates and host material, leading to improved guest selectivity and uptake capacity. In this study, we demonstrate the influence of the interaction among adsorbates and substrate, controlled by the pore environment and species of adsorbates, on the adsorption behaviour. We report the unique CO adsorption behaviour of MOF-205 due to distinct pore geometry. The precise analysis through gas-adsorption crystallography with molecular simulation shows that capillary condensation of CO in MOF-205 occurs preferentially in the large dodecahedral pore rather than the small tetrahedral pore, because the interaction of CO with MOF-205 framework is weaker than that among CO molecules, while Ar and N are sequentially filled into two different pores of MOF-205 according to their size. Comparison of the materials with different pore environments reveals that the relative strength of the adsorbate-adsorbate and adsorbate-substrate interaction gives rise to different shapes of isotherms.
为了更好地设计吸附剂，了解被吸附物与主体材料之间的分子间相互作用非常重要，这有助于提高客体选择性和吸附容量。在本研究中，我们展示了由孔隙环境和被吸附物种类控制的被吸附物与底物之间的相互作用对吸附行为的影响。我们报道了由于独特的孔几何结构，MOF-205具有独特的CO吸附行为。通过气体吸附晶体学与分子模拟的精确分析表明，MOF-205中CO的毛细管凝聚优先发生在大的十二面体孔中，而不是小的四面体孔中，因为CO与MOF-205骨架的相互作用比CO分子之间的相互作用弱，而Ar和N则根据它们的大小依次填充到MOF-205的两个不同孔中。对具有不同孔隙环境的材料进行比较发现，被吸附物-被吸附物和被吸附物-底物相互作用的相对强度导致了不同形状的等温线。
