Characterization of nanostructured organic-inorganic hybrid materials using advanced solid-state NMR spectroscopy
We demonstrate the applications of several novel techniques in solid-state nuclear magnetic resonance spectroscopy (SSNMR) to the structural studies of mesoporous organic-inorganic hybrid catalytic materials. Most of these latest capabilities of solid-state NMR were made possible by combining fast magic angle spinning (at {ge} 40 kHz) with new multiple RF pulse sequences. Remarkable gains in sensitivity have been achieved in heteronuclear correlation (HETCOR) spectroscopy through the detection of high-{gamma} ({sup 1}H) rather than low-{gamma} (e.g., {sup 13}C, {sup 15}N) nuclei. This so-called indirect detection technique can yield through-space 2D {sup 13}C-{sup 1}H HETCOR spectra of surface species under natural abundance within minutes, a result that earlier has been out of reach. The {sup 15}N-{sup 1}H correlation spectra of species bound to a surface can now be acquired, also without isotope enrichment. The first indirectly detected through-bond 2D {sup 13}C-{sup 1}H spectra of solid samples are shown, as well. In the case of 1D and 2D {sup 29}Si NMR, the possibility of generating multiple Carr-Purcell-Meiboom-Gill (CPMG) echoes during data acquisition offered time savings by a factor of ten to one hundred. Examples of the studied materials involve mesoporous silica and mixed oxide nanoparticles functionalized with various types of organic groups, where solid-state NMR provides the definitive characterization.
- Research Organization:
- Ames Lab., Ames, IA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- DE-AC02-07CH11358
- OSTI ID:
- 984443
- Report Number(s):
- IS-J 7497; TRN: US201015%%1181
- Journal Information:
- Materials Research Society Symposia Proceedings, Vol. 1184
- Country of Publication:
- United States
- Language:
- English
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