メチルアモニウム,ホルマミジニウム,セシウムチンの局所構造と動態
Dominik J Kubicki1,2, Daniel Prochowicz3, Elodie Salager4,5
1Cavendish Laboratory, Department of Physics (CB3 0HE), University of Cambridge, JJ Thomson Avenue, Cambridge, U.K.
Journal of the American Chemical Society
|April 4, 2020
まとめ
固体 NMR 方法を開発し,チンのハリドペロブスキットを研究しました. この技術は,それらの局所構造,分解経路,イオン動態を明らかにし,以前の試行錯誤アプローチの限界を克服します.
科学分野:
- 材料科学
- 固体化学
- スペクトロスコーピー
背景:
- オーガニック・インオーガニック・ティン (II) ハリド・ペロブスキットは,新興光電子材料である.
- 鉛の類型と比較して性能と安定性が低いため,開発が妨げられています.
- 原子レベルでの微細構造を 探究する方法の欠如が 進歩を制限しています
研究 の 目的:
- チン (II) ハリドペロブスキットの分析のための固体 NMR プロトコルを開発する.
- 地元の構造,混合ハリドの行動,分解経路を調査する.
- イオンダイナミクスを定量化し 物質の安定性を理解する
主な方法:
- 固体 NMR プロトコルの開発と適用
- 縦横のリラクゼーション時間の分析は,大きさの6つの順序をカバーします.
- 温度の変動による多領域リラクゼーション測定
主要な成果:
- 局所構造と組成を調べる方法としてSn NMRを確立した.
- ハライドの混合行動:Cl/BrとI/Brは固体合金を形成し,I/Clは混合が限られている.
- 解明された分解経路は,乱れた製品と金属亜鉛を明らかにし,高伝導性を説明する可能性がある.
結論:
- SN NMRはチンのハリドペロブスキットの微細構造と安定性を理解するために不可欠である.
- イオンダイナミクスは,混合ハリド系におけるハリドの均質化に寄与する.
- 開発されたNMRプロトコルは,これらのペロブスキットの合理的な設計と性能の改善を促進します.
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