Kemp Kingsley Christian, Mayoral Alvaro, Hong Suk Bong
Center for Ordered Nanoporous Materials Synthesis, Division of Environmental Science and Engineering, POSTECH, Pohang 37673, Korea.
Instituto de Nanociencia y Materiales de Aragon (INMA), Spanish National Research Council (CSIC), Universidad de Zaragoza, 12, Calle de Pedro Cerbuna, 50009 Zaragoza, Spain.
J Am Chem Soc. 2023 Oct 25;145(42):23300-23307. doi: 10.1021/jacs.3c08700. Epub 2023 Oct 13.
Here, we present the synthesis of / and / intergrowth zeolites using 2-isopropylimidazolium-based cations as organic structure-directing agents (OSDAs) in concentrated fluoride media and their local structural properties. Phase selectivity in the synthesis of zeolite intergrowths was found to differ according to the concentration of OSDA cations and fluoride anions in the synthesis mixture as well as to the type of OSDA employed. Molecular modeling results suggest that the crystallization of intergrowth zeolites in fluoride media may be kinetically rather than thermodynamically controlled, as in ordered zeolites. C-corrected STEM analysis of / crystals synthesized at HF/OSDA = 2.0 in the presence of 2-isopropyl-1,3-dipropylimidazolium ions as an OSDA indicates the existence of previously unobserved - intergrowth along the [100] direction, leading to a partial blockage of 10-ring channels.
在此，我们展示了在浓氟介质中使用基于2-异丙基咪唑鎓的阳离子作为有机结构导向剂（OSDAs）合成/和/共生沸石及其局部结构性质。发现沸石共生体合成中的相选择性因合成混合物中OSDA阳离子和氟阴离子的浓度以及所用OSDA的类型而异。分子模拟结果表明，氟介质中共生沸石的结晶可能像有序沸石一样受动力学而非热力学控制。在作为OSDA的2-异丙基-1,3-二丙基咪唑鎓离子存在下，HF/OSDA = 2.0时合成的/晶体的C校正STEM分析表明，沿[100]方向存在先前未观察到的 - 共生，导致10元环通道部分堵塞。
