TRAPDOR double-resonance and high-resolution MAS NMR for structural and template studies in zeolite ZSM-5 |
| |
Authors: | Anuji Abraham Roel Prins Jeroen A. van Bokhoven Ernst R.H. van Eck Arno P.M. Kentgens |
| |
Affiliation: | 1. Institute for Chemical and Bioengineering, Swiss Federal ETH Zurich, Zurich 8093, Switzerland;2. Department of Physical Chemistry – Solid-State NMR, Institute for Molecules and Materials, Radboud University of Nijmegen, Heyendaalseweg 135, 6525 AJ Nijmegen, Netherlands |
| |
Abstract: | A combination of 27Al magic-angle spinning (MAS)/multiple-quantum (MQ) MAS, and 27Al–{14N} TRAnsfer of Population in DOuble-Resonance (TRAPDOR) nuclear magnetic resonance (NMR) was used to study aluminium environments in zeolite ZSM-5. 27Al–{14N} TRAPDOR experiments, in combination with 14N NMR were employed to show that the two tetrahedral peaks observed in the 27Al MAS/3Q-MAS spectra of as-synthesized ZSM-5 are due to aluminium atoms occupying crystallographically inequivalent T-sites. A 13C–{27Al} TRAPDOR experiment was used to study the template, tetrapropyl ammonium bromide (TPABr), in the three-dimensional pore system of ZSM-5. The inequivalency of the methyl groups of TPA was observed in the 13C–{27Al} TRAPDOR spectra of as-synthesized ZSM-5 and the motion of the methyl end of the propyl chain appeared to be more restricted in the sinusoidal channel than in the straight channel. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|