Direct Observation of the Active Center for Methane Dehydroaromatization Using an Ultrahigh Field 95Mo NMR Spectroscopy
State Key Laboratory of Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, P.R. China, and Pacific Northwest National Laboratory, P. O. Box 999, MS K8-98, Richland, Washington 99352
Received December 14, 2007
The use of an ultrahigh magnetic field spectrometer and 95Mo isotope enrichment facilitate the direct observation of the local structure of Mo species on Mo/zeolite catalysts by 95Mo NMR. Top trace: The experimental 95Mo NMR spectrum of 6Mo/HZSM-5. Bottom traces: The simulated overall spectrum (orange), the spectral component corresponding to MoO3 (purple), and the component corresponding to the exchanged Mo species (green). The exchanged Mo species proved to be the active center for the methane dehydroaromatization (MDA) reaction.