Jo Donghui, Zhao Jingjing, Cho Jung, Lee Jeong Hwan, Liu Yang, Liu Chang-Jun, Zou Xiaodong, Hong Suk Bong
Center for Ordered Nanoporous Materials Synthesis, Division of Environmental Science and Engineering, POSTECH, Pohang, 37673, Korea.
Berzelii Center EXSELENT on Porous Materials, Department of Materials and Environmental Chemistry, Stockholm University, 106 91, Stockholm, Sweden.
Angew Chem Int Ed Engl. 2020 Sep 28;59(40):17691-17696. doi: 10.1002/anie.202007804. Epub 2020 Aug 11.
Herein we report the synthesis, structure solution, and catalytic properties of PST-24, a novel channel-based medium-pore zeolite. This zeolite was synthesized via the excess fluoride approach. Electron diffraction shows that its structure is built by composite cas-zigzag (cas-zz) building chains, which are connected by double 5-ring (d5r) columns. While the cas-zz building chains are ordered in the PST-24 framework, the d5r columns adopt one of two possible arrangements; the two adjacent d5r columns are either at the same height or at different heights, denoted arrangements S and D, which can be regarded as open and closed valves that connect the channels, respectively. A framework with arrangement D only has a 2D 10-ring channel system, whereas that with arrangement S only contains 3D channels. In actual PST-24 crystals, the open and closed valves are almost randomly dispersed to yield a zeolite framework where the channel dimensionality varies locally from 2D to 3D.
在此，我们报道了一种新型的基于通道的中孔沸石PST-24的合成、结构解析及催化性能。该沸石是通过过量氟化物法合成的。电子衍射表明其结构由复合的cas-锯齿形（cas-zz）构建链构成，这些链通过双5元环（d5r）柱连接。虽然cas-zz构建链在PST-24骨架中是有序的，但d5r柱采用两种可能排列方式之一；两个相邻的d5r柱要么处于相同高度，要么处于不同高度，分别表示为排列S和排列D，它们可分别视为连接通道的打开和关闭的阀门。仅具有排列D的骨架只有一个二维10元环通道系统，而具有排列S的骨架仅包含三维通道。在实际的PST-24晶体中，打开和关闭的阀门几乎随机分布，从而产生一种沸石骨架，其中通道维度在局部从二维变化到三维。
