Extremely Stable Zeolites Developed via Designed Liquid-Mediated Treatment
Extremely Stable Zeolites Developed via Designed Liquid-Mediated Treatment
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DOI：
10.1021/jacs.9b12709
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发表时间：
2020-02-26
影响因子：
15
通讯作者：
Wakihara, Toru
中科院分区：
文献类型：
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作者：
Iyoki, Kenta;Kikumasa, Kakeru;Wakihara, Toru
提高多孔材料在实际应用中的稳定性是极具挑战性的。铝硅酸盐沸石用于吸附和催化应用，其中它们有时暴露在高温蒸汽条件下（类似于1000摄氏度）。由于高硅沸石的降解源于其框架中的缺陷位点，因此迫切需要可行的缺陷修复方法。在此，我们提出了一种修复缺陷的方法，以创建非常稳定的高硅沸石。具有*BEA-， MFI-和mor型拓扑结构的高二氧化硅（SiO2/Al2O3 >240）沸石可以通过液体介导处理显著减少缺陷位点的数量而不使用额外的硅化剂来稳定。当暴露在极高的温度（900-1150摄氏度）蒸汽中时，稳定的沸石保持其结晶度和微孔体积，而母体商业沸石则完全降解。提出的自缺陷修复方法为物种通过多孔体的迁移提供了新的见解，并显著提高了沸石在恶劣环境中的实际适用性。
Improving the stability of porous materials for practical applications is highly challenging. Aluminosilicate zeolites are utilized for adsorptive and catalytic applications, wherein they are sometimes exposed to high-temperature steaming conditions (similar to 1000 degrees C). As the degradation of high -silica zeolites originates from the defect sites in their frameworks, feasible defect-healing methods are highly demanded. Herein, we propose a method for healing defects to create extremely stable high-silica zeolites. High -silica (SiO2/Al2O3 > 240) zeolites with *BEA-, MFI-, and MOR-type topologies could be stabilized by significantly reducing the number of defect sites via a liquid-mediated treatment without using additional silylating agents. Upon exposure to extremely high temperature (900-1150 degrees C) steam, the stabilized zeolites retain their crystallinity and micropore volume, whereas the parent commercial zeolites degrade completely. The proposed self-defect-healing method provides new insights into the migration of species through porous bodies and significantly advances the practical applicability of zeolites in severe environments.