ペロブスキートナノ結晶における欠陥耐性の限界:トラップ状態に対する局所静電電力の影響
Indy du Fossé1, Jence T Mulder1, Guilherme Almeida1
1Optoelectronic Materials Section, Faculty of Applied Sciences, Delft University of Technology, Van der Maasweg 9, 2629 HZ Delft, The Netherlands.
Journal of the American Chemical Society
|June 29, 2022
まとめ
鉛ハリドペロブスキートナノ結晶 (NCs) は欠陥耐性を示すが,表面Br-イオンは深い罠を作ることができる. 局所的な静電電位が これらの罠を説明し 特定のイオンによって受動させられます
科学分野:
- 材料科学
- 固体物理学
- 量子化学について
背景:
- 鉛ハリドペロブスキートナノ結晶 (NCs) は,その欠陥耐性で知られています.
- 低調整のイオンは通常,帯の縁の近くで浅い罠を形成すると考えられています.
- 表面のブランディングボンドは 深いトラップ状態を生成することが観察されています
研究 の 目的:
- ペロブスキートNCの欠陥耐久性についての伝統的な理解に挑戦する.
- 表面のブリオンによって引き起こされる 深いトラップ状態の形成を説明するために
- ペロブスキートNCの深層トラップの受動化のための戦略を提案する.
主な方法:
- 密度関数理論 (DFT) の計算
- 表面 Br- サイトにおける局所静電力の分析
- イオンパッシブ化戦略の調査
主要な成果:
- 表面の Br-サイトは不安定な静電電位を体験し, 振動する軌道を帯域の隙間に押し込みます.
- これらの深層トラップは 特定のイオンによって静電的に受動させられます
- パッシベーションは,コバルント表面結合なしのイオン相互作用によって発生する.
結論:
- ペロブスキートNCにおける欠陥耐久性に関する伝統的な見解は不完全である.
- 地元の環境と静電電位は 深い罠の形成に不可欠です
- イオンパッシベーションは 帯域の隙間から 深いトラップを排除する有効な戦略です
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