CaltechAUTHORS
  A Caltech Library Service

NMR Studies of the Hydrogen Storage Compound NaMgH_3

Shane, David T. and Corey, Robert L. and Bowman, Robert C., Jr. and Zidan, Ragaiy and Stowe, Ashley C. and Hwang, Son-Jong and Kim, Chul and Conradi, Mark S. (2009) NMR Studies of the Hydrogen Storage Compound NaMgH_3. Journal of Physical Chemistry C, 113 (42). pp. 18414-18419. ISSN 1932-7447. https://resolver.caltech.edu/CaltechAUTHORS:20091102-110641436

[img]
Preview
PDF - Supplemental Material
See Usage Policy.

134Kb

Use this Persistent URL to link to this item: https://resolver.caltech.edu/CaltechAUTHORS:20091102-110641436

Abstract

Hydrogen and ^(23)Na NMR were performed to 400 °C on NaMgH3 powder produced by reactive ball-milling of NaH and MgH2. The H resonance shows narrowing already at 100 °C as a narrow line superimposed on the broad, rigid-lattice signal. With increasing temperature, the fraction of spins in the narrow component grows smoothly, approaching 100% near 275 °C. This heterogeneous narrowing suggests a wide distribution of H motion rates. After annealing at 400 °C, the narrow component intensity at temperatures below 200 °C was substantially reduced and both H and ^(23)Na relaxation rates 1/T_1 were decreased. Thus, it appears that the high rates of H motion, particularly on first heating, are due to regions with poorly organized crystal structure. If this disorder could be maintained, this might be an avenue toward improved reaction kinetics of this or other hydrides. In the annealed sample, the activation energy for H diffusion is approximately 95 kJ/mol.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://dx.doi.org/10.1021/jp906414qDOIArticle
http://pubs.acs.org/doi/full/10.1021/jp906414q?cookieSet=1PublisherArticle
ORCID:
AuthorORCID
Bowman, Robert C., Jr.0000-0002-2114-1713
Hwang, Son-Jong0000-0002-3210-466X
Additional Information:© 2009 American Chemical Society. Received: July 7, 2009; Revised Manuscript Received: September 4, 2009. Publication Date (Web): September 25, 2009. The authors appreciate funding from the U.S. Department of Energy through Basic Energy Sciences grant DE-FG02-05ER46256. Characterization of the materials by J.G. Kulleck (XRD) is gratefully acknowledged. We thank Anup Gangopadhyay for measurements of magnetic susceptibility.
Funders:
Funding AgencyGrant Number
Department of Energy (DOE)DE-FG02-05ER46256
Issue or Number:42
Record Number:CaltechAUTHORS:20091102-110641436
Persistent URL:https://resolver.caltech.edu/CaltechAUTHORS:20091102-110641436
Official Citation:NMR Studies of the Hydrogen Storage Compound NaMgH3 David T. Shane, Robert L. Corey, Robert C. Bowman, Jr., Ragaiy Zidan, Ashley C. Stowe, Son-Jong Hwang, Chul Kim, Mark S. Conradi The Journal of Physical Chemistry C 2009 113 (42), 18414-18419
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:16537
Collection:CaltechAUTHORS
Deposited By: Tony Diaz
Deposited On:02 Nov 2009 20:12
Last Modified:03 Oct 2019 01:13

Repository Staff Only: item control page