表面からのリレーによる無機固体の大量核極化
Snædís Björgvinsdóttir1, Brennan J Walder1, Arthur C Pinon1
1Institut des Sciences et Ingéniere Chimiques , Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne , Switzerland.
Journal of the American Chemical Society
|June 3, 2018
まとめ
この研究では,陽子のない無機固体に対する新しい超極化技術が導入され,核磁気共鳴 (NMR) の感度が著しく向上しました. この方法では 感度が最大50倍に上がり 材料の分析が速くなります
科学分野:
- 固体核磁共振 (NMR) スペクトロシー
- 材料科学
- 量子情報科学
背景:
- 核磁共振 (NMR) は,無機物質の特徴づけに不可欠です.
- NMRの比較的低い感度は,陽子のない無機固体での使用を制限する.
- 現行のNMR技術は これらの材料の質量特性を分析するのに苦労しています
研究 の 目的:
- 陽子のない無機固体を高極化するための一般的な戦略を開発する.
- 従来のNMRスペクトロスコーピーの感度制限を克服する.
- 無機材料の構造と電子分析を より迅速かつ詳細にできるようにする.
主な方法:
- ホモ核スピン拡散を用いたインプレグネーションダイナミック核極化 (IDNP).
- 低γ (ガンマ) 核の直接的高極化.
- 陽子から表面ヘテロ核にハイパーポラライゼーションを転送するためのパルス冷却クロスポラライゼーション (PCCP).
主要な成果:
- 粉末のSnO2のSn NMRスペクトルの感度が50倍になった.
- 2500倍以上の取得時間の加速が実証されています.
- この方法をGaPの31P,CdのCdTe,α-クォーツのSiに成功裏に適用した.
結論:
- 開発されたハイパーポラライゼーション戦略は,陽子のない無機固体におけるNMR感受性を著しく高めます.
- この方法は,材料の性質を迅速かつ敏感に分析するための突破口を提供します.
- この技術は,半導体や酸化物を含む様々な無機材料に広く適用できます.
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