Jin Chun-Xin, Wang Yu, Gao Qiu-Shan, Yao Dan-Yang, Wang Si-Hong, Li Donghao, Shang Hai-Bo
Department of Chemistry, Yanbian University, Park Road 977, Yanji City, Jilin Province 133002, China.
State Key Laboratory of Separation Membranes and Membrane Processes, School of Material Science and Engineering, Tianjin Polytechnic University, Tianjin, 300387, China.
Dalton Trans. 2020 Feb 25;49(8):2437-2443. doi: 10.1039/c9dt04747f.
Exploring new zeolitic imidazolate frameworks (ZIFs) with specific topologies and pore structures is important for extending applications and improving performances. In this work, a new farfalle-shaped ZIF with an ordered hierarchical structure (named ZIF-F) was easily built with zinc acetate and 2-methylimidazole (MeIm) in an aqueous system at room temperature. The synthesis mechanism of ZIF-F is a dual-induction interaction of a solvent and zinc source based on the synthesis protocol of ZIF-8. The prepared ZIF-F is a 3-5 μm dispersible particle constructed from numerous nanoplates with the same building units as ZIF-8. ZIF-F has a rich 4 nm inter-particle spacing with a 0.1074 cm3 g-1 total pore volume and exhibits high thermo- and solvent stability. It is worth noting that crystal transformation could occur from ZIF-F to ZIF-8 in methanol via the dissolution-recrystallization route. Regarding the adsorption of Congo red (CR), ZIF-F exhibits better adsorption capacity (182.82 mg g-1) than ZIF-8 (149.25 mg g-1) with 6 times higher adsorption rate than that of ZIF-8 because of the positive effect of its larger pore size and hierarchical structure.
探索具有特定拓扑结构和孔结构的新型沸石咪唑酯骨架材料（ZIFs）对于扩展应用和提高性能具有重要意义。在这项工作中，在室温下于水体系中，使用醋酸锌和2-甲基咪唑（MeIm）轻松构建了一种具有有序分级结构的新型蝴蝶结形ZIF（命名为ZIF-F）。基于ZIF-8的合成方案，ZIF-F的合成机理是溶剂与锌源的双重诱导相互作用。制备的ZIF-F是一种3-5μm的可分散颗粒，由许多与ZIF-8具有相同构建单元的纳米片构成。ZIF-F具有丰富的4nm颗粒间距，总孔体积为0.1074cm³ g⁻¹，并且表现出高的热稳定性和溶剂稳定性。值得注意的是，在甲醇中，ZIF-F可通过溶解-重结晶途径转变为ZIF-8。关于刚果红（CR）的吸附，由于其较大的孔径和分级结构的积极作用，ZIF-F表现出比ZIF-8更好的吸附容量（182.82mg g⁻¹），吸附速率比ZIF-8高6倍。
