Jiang Zhi-Jie, Wang Ying, Luo Dong, Wei Rong-Jia, Lu Weigang, Li Dan
College of Chemistry and Materials Science, Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications, Jinan University, Guangzhou, 510632, China.
Angew Chem Int Ed Engl. 2024 Jul 1;63(27):e202403209. doi: 10.1002/anie.202403209. Epub 2024 May 27.
Metal-organic frameworks (MOFs) that exhibit dynamic phase-transition behavior under external stimuli could have great potential in adsorptive separations. Here we report on a zinc-based microporous MOF (JNU-80) and its reversible transformation between two crystalline phases: large pore (JNU-80-LP) and narrow pore (JNU-80-NP). Specifically, JNU-80-LP can undergo a dehydration-induced cluster consolidation under heat treatment, resulting in JNU-80-NP with a reduced channel that allows exclusion of di-branched hexane isomers while high adsorption of linear and mono-branched hexane isomers. We further demonstrate the fabrication of MOF-polymer composite (JNU-80-NP-block) and its application in the purification of di-branched isomers from liquid-phase hexane mixtures (98 % di-branched) at room temperature, affording the di-branched hexane isomers with 99.5 % purity and close to 90 % recovery rate over ten cycles. This work illustrates an interesting dehydration-induced cluster consolidation in MOF structure and the ensuing channel shrinkage for sieving di-branched hexane isomers, which may have important implications for the development of MOFs with dynamic behavior and their potential applications in non-thermal driven separation technologies.
在外部刺激下表现出动态相变行为的金属有机框架（MOF）在吸附分离方面可能具有巨大潜力。在此，我们报道了一种锌基微孔MOF（JNU - 80）及其在两个晶相之间的可逆转变：大孔（JNU - 80 - LP）和窄孔（JNU - 80 - NP）。具体而言，JNU - 80 - LP在热处理下可经历脱水诱导的簇聚并，生成JNU - 80 - NP，其通道变窄，能够排除二支链己烷异构体，同时对直链和单支链己烷异构体具有高吸附性。我们进一步展示了MOF - 聚合物复合材料（JNU - 80 - NP - block）的制备及其在室温下从液相己烷混合物（98%为二支链）中纯化二支链异构体的应用，在十个循环中得到纯度为99.5%且回收率接近90%的二支链己烷异构体。这项工作阐明了MOF结构中有趣的脱水诱导簇聚并以及随之而来的通道收缩以筛分二支链己烷异构体，这可能对具有动态行为的MOF的开发及其在非热驱动分离技术中的潜在应用具有重要意义。
