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Preparation of Fungal and Plant Materials for Structural Elucidation Using Dynamic Nuclear Polarization Solid-State NMR
Published on: February 12, 2019
Enhanced solid-state NMR correlation spectroscopy of quadrupolar nuclei using dynamic nuclear polarization.
Daniel Lee1, Hiroki Takahashi, Aany S L Thankamony
1Laboratoire de Chimie Inorganique et Biologique, UMR-E CEA/UJF-Grenoble, Institut Nanosciences et Cryogénie, France.
Journal of the American Chemical Society
|October 26, 2012
Summary
Dynamic Nuclear Polarization (DNP) significantly enhances solid-state NMR spectroscopy (SSNMR), enabling rapid, interface-selective studies of mesoporous alumina. This breakthrough allows detailed atomic-scale structural determination of quadrupolar nuclei in catalysis materials.
Area of Science:
- Solid-state NMR Spectroscopy
- Materials Science
- Surface Chemistry
Background:
- Quadrupolar nuclei present challenges for conventional solid-state NMR spectroscopy due to low cross-polarization and dipolar recoupling efficiency.
- Mesoporous alumina is an advanced material with industrial applications, requiring detailed structural characterization.
- Interface-selective structural information is crucial for understanding material properties and performance.
Purpose of the Study:
- To demonstrate a sensitivity enhancement technique for solid-state NMR spectroscopy (SSNMR) using Dynamic Nuclear Polarization (DNP).
- To record interface-selective 2D dipolar correlation spectra of quadrupolar nuclei ((27)Al) in mesoporous alumina.
- To determine the atomic-scale structure and interfacial coordination of aluminum species in mesoporous alumina.
Main Methods:
- Utilized Dynamic Nuclear Polarization (DNP) to enhance sensitivity in solid-state NMR spectroscopy (SSNMR).
- Performed interface-selective (27)Al-(27)Al two-dimensional dipolar correlation experiments on mesoporous alumina.
- Conducted experiments at low temperature (approx. 103 K) and 9.4 T magnetic field.
Main Results:
- Achieved 4-5 orders of magnitude of time savings compared to conventional SSNMR.
- Successfully recorded interface-selective (27)Al-(27)Al 2D dipolar correlation spectra.
- Observed and determined the role of pentacoordinated aluminum in bridging interfacial tetra- and hexacoordinated aluminum species.
- Obtained crucial structural information in just 4 hours, which would be impossible under standard conditions.
Conclusions:
- DNP-enhanced SSNMR overcomes limitations in studying quadrupolar nuclei.
- This technique enables rapid, atomic-scale structural determination of interfacial species in materials like mesoporous alumina.
- Opens new avenues for applying SSNMR to catalysis materials and other systems with quadrupolar nuclei.
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