High-temperature in-situ magic angle spinning NMR studies of chemical reactions on catalysts

1992 ◽  
Vol 96 (20) ◽  
pp. 8106-8111 ◽  
Author(s):  
F. Gregory Oliver ◽  
Eric J. Munson ◽  
James F. Haw
Keyword(s):  
High Temperature ◽  
Chemical Reactions ◽  
Magic Angle Spinning ◽  
Magic Angle ◽  
Nmr Studies ◽  
Angle Spinning

Continuous Flow Hyper-Polarized 129Xe-Mas Nmr Studies of Microporous Materials.

2003 ◽  
Vol 775 ◽  
Author(s):  
Andrei Nossov ◽  
Flavien Guenneau ◽  
Marie-Anne Springuel-Huet ◽  
Valérie Montouillout ◽  
Jean-Pierre Cognec ◽  
...  
Keyword(s):  
Continuous Flow ◽  
Nmr Spectra ◽  
Magic Angle Spinning ◽  
Mas Nmr ◽  
Magic Angle ◽  
Original Design ◽  
Nmr Studies ◽  
Powder Samples ◽  
Angle Spinning

Summary:A Magic Angle Spinning (MAS) NMR probe has been designed allowing the in-situ measurements of NMR spectra of working catalyst. The probe was built following the original design of M. Hunger [Hunger, 1995 #2]. It allows the magic angle spinning of powder samples up to 3.5 kHz, under gas flowing conditions, and at temperatures up to 573K.

Lithium-7 NMR Studies of Li1−xCoO2 Battery Cathodes

1994 ◽  
Vol 369 ◽  
Author(s):  
B. Ouyang ◽  
X. Cao ◽  
H.W. Lin ◽  
S. Slane ◽  
S. Kostov ◽  
...  
Keyword(s):  
Chemical Shifts ◽  
Parent Compound ◽  
Magic Angle Spinning ◽  
Magic Angle ◽  
Line Broadening ◽  
X Ray Diffraction ◽  
Nmr Studies ◽  
Relaxation Measurements ◽  
Angle Spinning

AbstractLithium-deficient cathode materials Li1-xCoO2 where x = 0.1, 0.4 and 0.6 were prepared electrochemically from the stoichiometric parent compound (x = 0.0).The materials were observed to be air-stable, and x-ray diffraction characterization yielded good agreement with the in situ studies of Dahn and co-workers, regarding changes in lattice parameters. In addition to both static and magic angle spinning (MAS) 7Li NMR, measurements, the samples were investigated by EPR and cobalt K-edge NEXAFS. The removal of Li is accompanied by compensating electrons from the Co d-orbitals, asevidenced by both shifts in the NEXAFS peak and the observation of EPR signals due to spins localized on the Co ions. These spins, in turn, result in dramatic 7Li chemical shifts (89 ppm for x = 0.6) and line broadening. Whereas MAS analysis of Li0.9CoO2 indicates two magnetically inequivalent Li sites, the spectra becometoo broad to resolve different sites for higher values of x. Finally NMR linewidth and spinlattice relaxation measurements as a function of temperature suggest a modest increase in Li+ ion mobility for Li-deficient samples as compared to the parent compound.

Development and Application of In Situ High-Temperature, High-Pressure Magic Angle Spinning NMR

2018 ◽  
pp. 1073-1091 ◽  
Author(s):  
Nicholas R. Jaegers ◽  
Mary Y. Hu ◽  
David W. Hoyt ◽  
Yong Wang ◽  
Jian Zhi Hu
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Magic Angle Spinning ◽  
Magic Angle ◽  
Angle Spinning ◽  
High Temperature High Pressure
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