Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-24T12:31:30.888Z Has data issue: false hasContentIssue false

93Nb Solid State NMR of High Surface Area Niobium Oxides

Published online by Cambridge University Press:  26 February 2011

Luis Smith
Affiliation:
[email protected] Clark University Chemsitry 950 Main St Worcester MA 01610 United States 508-793-7753 508-793-8861
Xuefeng Wang
Affiliation:
[email protected] Clark University Carlson School of Chemistry and Biochemistry 950 Main St Worcester MA 01610 United States
Get access

Abstract

The local environment of niobium in oxides reflects the perturbations in bond strength that affect the acidity of oxygen atoms in the structure. To understand the relationship between metal environment and properties, 93Nb solid state NMR has been used to measure the electric field gradient and chemical shift anisotropy for layered niobates with either alkali cations or protons at the material surface. In order to determine these parameters, a variety of techniques have been applied to extract information for the multiple environments located in these oxides. Variable offset cumulative echo spectra were collected on static samples at multiple magnetic fields, 4.7 T, 9.4 T and 14.1 T. RAPT enhanced QPASS data were collected at 9.4 T to extract quadrupolar-coupling information without the influence of chemical shift anisotropy. Data from KCa2Nb3O10 and an acid exchanged form was collected and two distinct quadrupolar environments were observed. Acid exchange altered the isotropic chemical shift but did not significantly affect the electric field gradient or the chemical shift anisotropy.

Type
Research Article
Copyright
Copyright © Materials Research Society 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. Bhuvanesh, N.S.P. and Gopalakrishnan, J., J. Mater. Chem., 7, 2297 (1997).Google Scholar
2. Kwak, H.T., Prasad, S., Clark, T. and Grandinetti, P.J., J. Magn. Reson., 160, 107 (2003).Google Scholar
3. Smith, L.J. and Seith, C., J. Magn. Reson., 179, 164 (2006).Google Scholar
4. Jacobson, A.J., Lewandowski, J.T. and Johnson, J.W., J. Less-Common Metals, 116, 137 (1986).Google Scholar
5. Hardin, S., Hay, D., Millikan, M., Sanders, J.V. and Turney, T.W., Chem. Mater., 3, 977 (1991).Google Scholar
6. Bureau, B., Silly, G., Buzare, J.Y., Legein, C. and Massiot, D., Solid State Nucl. Mag. Reson., 14, 181 (1999).Google Scholar
7. Aurentz, D.J., Vogt, F.G., Mueller, K.T. and Benesi, A.J., J. Magn. Reson., 138, 320 (1999).Google Scholar
8. Grandinetti, P.J., RMN, Version 1.3.0 (2005).Google Scholar
9. Massiot, D., Fayon, F., Capron, M., King, I., Calve, S. Le, Alonso, B., Durand, J.O., Bujoli, B., Gan, Z.H. and Hoatson, G., Magn. Reson. Chem., 40, 70 (2002).Google Scholar
10. Eichele, K. and Wasylishen, R.E., WSOLIDS NMR Simulation Package, Version 1.17.30 (2001).Google Scholar
11. Jehng, J.M. and Wachs, I.E., Chem. Mater., 3, 100 (1991).Google Scholar
12. Jehng, J.M. and Wachs, I.E., J. Phys. Chem., 95, 7373 (1991).Google Scholar
13. Fukuoka, H., Isami, T. and Yamanaka, S., J. Solid State Chem., 151, 40 (2000).Google Scholar
14. Massiot, D., Montouillout, V., Fayon, F., Florian, P. and Bessada, C., Chem. Phys. Lett., 272, 295 (1997).Google Scholar
15. Prasad, S., Kwak, H.T., Clark, T. and Grandinetti, P.J., J. Am. Chem. Soc., 124, 4964 (2002).Google Scholar
16. Yao, Z., Kwak, H.T., Sakellariou, D., Emsley, L. and Grandinetti, P.J., Chem. Phys. Lett., 327, 85 (2000).Google Scholar