鉛ハリドペロフスキットの非線形キャリア相互作用と欠陥の役割
Ajay Ram Srimath Kandada1, Stefanie Neutzner1,2, Valerio D'Innocenzo1,2
1Center for Nano Science and Technology @Polimi, Istituto Italiano di Tecnologia , via Giovanni Pascoli 70/3, 20133 Milano, Italy.
Journal of the American Chemical Society
|September 27, 2016
まとめ
刺激相関光発光 (ECPL) スペクトロスコピーを用いて鉛ハリドペロブスキットの欠陥を調査すると,浅い欠陥が光発光量子収量を増やすことが明らかになる. この研究は,安定した,信頼性の高い光電子装置のための材料工学を導く.
科学分野:
- 材料科学
- 固体物理学
- 光電子機器
背景:
- 鉛ハリドペロブスキットは溶液の処理性を提供しますが,安定性と信頼性に影響を与える意図しない欠陥に苦しんでいます.
- 欠陥の性質とデバイスの動作におけるその役割を理解することは,ペロブスキート光電子機器の市場規模での応用にとって極めて重要です.
研究 の 目的:
- ECPL光譜を用いて,鉛ブロミドペロブスキットのキャリア再結合ダイナミクスと欠陥エネルギーを調べる.
- キャリアトラッピングの動態を定量的に記述し,非放射性損失チャネルとの製造条件を相関させる.
主な方法:
- 刺激相関光発光 (ECPL) スペクトロスコーピー
- キャリアトラッピングのダイナミクスを記述するショックリー-リード-ホール形式論の一般化.
- 欠陥エネルギーと多体相互作用の分析
主要な成果:
- ポリクリスタリン鉛ブロミドペロブスキートフィルムに 深いと浅いキャリアトラップが確認された.
- 半導体で示された浅い欠陥 (伝導帯域以下20 meV) は,光発光量子出力を高めます.
- 関連した光媒介システムによる高興奮密度での非放射性アウガー再結合の抑制が観察された.
- コロイドナノ結晶をほぼ欠陥のないシステムとして示し,主にオーガーのような相互作用によって非放射性解消した.
結論:
- ECPL光譜は,ペロブスキットの欠陥エネルギーと再結合ダイナミクスを特定するための繊細なツールです.
- 材料工学の戦略は,製造条件と特定された非放射性損失チャネルを相関させることで導かれます.
- 浅い欠陥はペロブスキットに有益であり,コロイドナノ結晶は高度な光電子機器の欠陥最小化システムへの経路を提供します.
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