Hong Zhe, Deng Lihua, Wang Fanglin, Zhu Fangyu, Fang Yingsen, Song Li, Li Lei, Zhu Zhirong
College of Biological, Chemical Sciences and Engineering, Jiaxing University, Jiaxing, Zhejiang 314001, China.
School of Chemical Science and Engineering, Tongji University, Shanghai 200092, China.
Inorg Chem. 2024 Oct 28;63(43):20888-20899. doi: 10.1021/acs.inorgchem.4c03697. Epub 2024 Oct 19.
ZSM-5 zeolites with accessible micropore architecture and tunable acid-base sites are important shape-selective catalysts. However, the presence of exposed straight channels and the external acid-base sites of conventional ZSM-5 has a negative impact on shape selectivity. Herein, we report on the direct synthesis of an intergrowth ZSM-5 zeolite mimicking the mortise-tenon joints. It can be revealed by various methods that the mortise-tenon ZSM-5 shows an inverse Al gradient from the surface to the core of the zeolite. More importantly, the sinusoidal channels predominantly opened to their external surfaces are constructed. The shape-selective capability of the ZSM-5 zeolite has been fully exploited due to the intrinsic inert external surface and unique sinusoidal channel features, thereby resulting in high styrene selectivity (>90%) and good catalytic stability (>100 h) in the toluene side-chain alkylation reaction. In addition, in situ DRIFTS confirms that this intergrowth ZSM-5 contributes to the formation of more active intermediates of HCOO* and HCO*, which is another reason responsible for the superior performance.
具有可及微孔结构和可调酸碱位点的ZSM-5沸石是重要的择形催化剂。然而，传统ZSM-5暴露的直通道和外部酸碱位点对择形性有负面影响。在此，我们报道了一种模仿榫卯结构的共生ZSM-5沸石的直接合成。通过各种方法可以发现，榫卯结构的ZSM-5从沸石表面到核心呈现出反向的铝梯度。更重要的是，构建了主要向其外表面开放的正弦通道。由于其固有的惰性外表面和独特的正弦通道特征，ZSM-5沸石的择形能力得到了充分发挥，从而在甲苯侧链烷基化反应中具有高苯乙烯选择性（>90%）和良好的催化稳定性（>100小时）。此外，原位漫反射红外傅里叶变换光谱证实，这种共生ZSM-5有助于形成更多的HCOO和HCO活性中间体，这是其优异性能的另一个原因。
