文献类型：期刊文献

英文题名：Synthesis of core-shell ZSM-5 zeolite with passivated external surface acidity by b-oriented thin silicalite-1 shell using a self-assembly process

作者：Yi, Dezhi[1];Xu, Xin[2];Meng, Xuan[1];Liu, Naiwang[1];Shi, Li[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Northwestern Univ, Appl Phys, Evanston, IL 60208 USA

年份：2019

卷号：26

期号：6

起止页码：1767

外文期刊名：JOURNAL OF POROUS MATERIALS

收录：;EI(收录号：20192507072921);WOS:【SCI-EXPANDED(收录号:WOS:000495414300020)】；

基金：This project was financially supported by the National Science Foundation for Young Scientists of China (No. 21706065), the Open Project of State Key Laboratory of Chemical Engineering (SKL-ChE-18C02), the China Postdoctoral Science Foundation (No. 2017M621389) and the Shanghai Sailing Program (No. 18YF1406300).

语种：英文

外文关键词：ZSM-5@silicalite-1; Self-assembly; b-Oriented; Acidity; Heterocatalysis

摘要：A core-shell HZSM-5@silicalite-1 zeolite coated with a relatively continuous b-oriented thin silicalite-1 shell has been synthesized by a self-assembly method of reversing the negative surface charge of ZSM-5 crystals before the secondary hydrothermal crystallization. The growth orientation of shell crystals is confirmed by electron microscopy technology. N-2 adsorption-desorption, X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscope with energy-dispersive X-ray spectrometry (STEM-EDS) measurements reveal that the core ZSM-5 crystals are coated with a relatively continuous monocrystal-thick silicalite-1 shell. The surface acidity analysis (Pyridine-FTIR and 2,4,6-collidine-FTIR) combined with the two probe chemical reactions using molecules that are either too large or adequately sized to access MFI pores has confirmed the passivation of external surface acid sites without hindering the intrinsic activity of the parent HZSM-5, which is consistent with the results from the electron microscopy and textural analysis.