TY - JOUR

T1 - Local Structures of Two-Dimensional Zeolites — Mordenite and ZSM-5 — Probed by Multinuclear NMR

AU - Shelyapina, Marina

AU - Yocupicio-Gaxiola, Rosario I.

AU - Zhelezniak, Iuliia V.

AU - Chislov , Mikhail V.

AU - Antunez-Garcia, Joel

AU - Murrieta-Rico, Fabian N.

AU - Galván, Donald Homero

AU - Petranovskii, Vitalii

AU - Fuentes-Moyado, Sergio

N1 - Publisher Copyright: © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

PY - 2020/10/13

Y1 - 2020/10/13

N2 - Mesostructured pillared zeolite materials in the form of lamellar phases with a crystal structure of mordenite (MOR) and ZSM-5 (MFI) were grown using CTAB as an agent that creates mesopores, in a one-pot synthesis; then into the CTAB layers separating the 2D zeolite plates were introduced by diffusion the TEOS molecules which were further hydrolyzed, and finally the material was annealed to remove the organic phase, leaving the 2D zeolite plates separated by pillars of silicon dioxide. To monitor the successive structural changes and the state of the atoms of the zeolite framework and organic compounds at all the steps of the synthesis of pillared MOR and MFI zeolites, the nuclear magnetic resonance method (NMR) with magic angle spinning (MAS) was applied. The 27Al and 29Si MAS NMR spectra confirm the regularity of the zeolite frameworks of the as synthetized materials. Analysis of the 1H and 13C MAS NMR spectra and an experiment with variable contact time evidence a strong interaction between the charged “heads” –[N(CH3)3]+ of CTAB and the zeolite framework at the place of [AlO4]− location. According to 27Al and 29Si MAS NMR the evacuation of organic cations leads to a partial but not critical collapse of the local zeolite structure

AB - Mesostructured pillared zeolite materials in the form of lamellar phases with a crystal structure of mordenite (MOR) and ZSM-5 (MFI) were grown using CTAB as an agent that creates mesopores, in a one-pot synthesis; then into the CTAB layers separating the 2D zeolite plates were introduced by diffusion the TEOS molecules which were further hydrolyzed, and finally the material was annealed to remove the organic phase, leaving the 2D zeolite plates separated by pillars of silicon dioxide. To monitor the successive structural changes and the state of the atoms of the zeolite framework and organic compounds at all the steps of the synthesis of pillared MOR and MFI zeolites, the nuclear magnetic resonance method (NMR) with magic angle spinning (MAS) was applied. The 27Al and 29Si MAS NMR spectra confirm the regularity of the zeolite frameworks of the as synthetized materials. Analysis of the 1H and 13C MAS NMR spectra and an experiment with variable contact time evidence a strong interaction between the charged “heads” –[N(CH3)3]+ of CTAB and the zeolite framework at the place of [AlO4]− location. According to 27Al and 29Si MAS NMR the evacuation of organic cations leads to a partial but not critical collapse of the local zeolite structure

KW - lamellar 2D zeolites

KW - pillared zeolites

KW - Mordenite

KW - ZSM-5

KW - CTAB

KW - NMR

KW - Lamellar 2D zeolites

KW - Pillared zeolites

KW - CHAIN DYNAMICS

KW - DESIGN

KW - SOLID-STATE NMR

KW - ONE-POT SYNTHESIS

KW - PHASE-TRANSITIONS

KW - SURFACTANTS

KW - RATIO

KW - mordenite

KW - SI-29 NMR

KW - SPECTROSCOPY

KW - ZSM-5 ZEOLITES

UR - http://www.scopus.com/inward/record.url?scp=85093705946&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/e9846e15-b3e4-336d-b395-fc70a1722eb4/

U2 - 10.3390/molecules25204678

DO - 10.3390/molecules25204678

M3 - Article

C2 - 33066351

VL - 25

JO - Molecules

JF - Molecules

SN - 1420-3049

IS - 20

M1 - 4678

ER -