混合カチオン (MA) x(FA) 1-xPbI3の混合ペロブスキートによる固体MRI
Dominik J Kubicki1, Daniel Prochowicz2,3, Albert Hofstetter1
1Laboratory of Magnetic Resonance, Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) , CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|June 24, 2017
まとめ
この研究は,固体NMRを用いたハイブリッド混合カチオンペロブスキットのカチオン再方向化ダイナミクスを明らかにした. これらのダイナミクスはキャリア寿命と相関しており,光伏ペロブスキットの電荷キャリアのポラロン性質を示唆している.
科学分野:
- 材料科学
- 固体化学
- 太陽光発電
背景:
- 混合カトンの有機鉛ハリドペロブスキットは,最大22%の電力変換効率を達成する太陽電池の主要な材料です.
- これらの高性能ペロブスキットは,光伏の性質を高めるために複数のカチオンを使用します.
研究 の 目的:
- ヒブリッド混合カチオン形式アミジニウム (FA) /メチルアモニウム (MA) 鉛ハリドペロブスキートのカチオン再定向ダイナミクスに関する最初の定量的なデータを提供する.
- カチオン再定位の動態,顕微鏡の相組成,および (MA) x (FA) 1-xPbI3におけるMA/FA比を解明する.
主な方法:
- 固体マジック・アングルスピニング (MAS) 核磁気共振 (NMR) スペクトロスコーピーは14N,2H,13C,および1H原子核を使用します.
- 100 Kから330 Kの間の変動温度の研究が行われました.
主要な成果:
- これらのハイブリッド・ペロブスキットで,カチオン再方向化ダイナミクスに関する定量的なデータは初めて得られた.
- 研究により,顕微鏡相組成とメチラモニウム (MA) /フォームミジニウム (FA) の比率を決定した.
- カチオン再定位率は,以前に報告されたキャリア寿命と顕著な相関関係を示した.
結論:
- 観測されたカチオンダイナミクスとキャリア寿命の間の相関は,光伏ペロフスキットの電荷キャリアのポラロン性質の証拠を提供します.
- このダイナミクスを理解することは,ペロブスキート太陽電池の性能と安定性を最適化するために重要です.
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