プロピラモニウムを使用したステップとフラット層のハリドペロフスキットの2Dから1Dの電子次元
Justin M Hoffman1, Xiaoyang Che2, Siraj Sidhik3
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|June 28, 2019
まとめ
Ruddlesden-Popper (RP) とステップのような (SL) 構造を含む新しいプロピラモニウムベースの2Dハイブリッドハライドペロブスキットは,光電子アプリケーションのための調整可能なバンドギャップとアニゾトロプ的電子特性を提供します.
科学分野:
- 材料科学
- 固体物理学
- 光電子機器
背景:
- 二次元の (2D) ハリドペロブスキットは,3Dの同位体よりも安定性が向上したため,光電子工学のために探求されています.
- プロピラモニウム (PA+) カチオンが導入され,新しいペロブスキート構造が形成されます.
研究 の 目的:
- プロピラモニウム (PA+) カチオンによる新しい2Dペロブスキート構造の合成と特徴付け.
- これらの新材料の電子的および光学的性質を調査する.
- 太陽電池の応用の可能性を評価する
主な方法:
- Ruddlesden-Popper (RP) とステップ型 (SL) のペロブスキート構造の合成
- バンドギャップを特定するための光学的な特徴付け.
- 電子構造分析のための密度関数理論 (DFT) の計算.
- 電気抵抗を測定する
- 太陽電池の製造とテスト
主要な成果:
- RP構造 ((PA) 2 ((MA) n-1PbnI3n+1) は,調節可能なブルーシフトバンドギャップ (1.90-2.03 eV) とアニゾトロプ的伝導性を示す.
- SL構造 ((PA) 2 ((MA) m-1Pb2Im+2) は,より大きなブルーシフト (2.53-2.93 eV) を示し,電子的に1D量子ワイヤーである.
- RP結晶は強い光反応を示し,SL材料はイオン輸送の優位性を示し,光反応を示さない.
- RP構造 (n=3) で製造された太陽電池は,最低限のヒステレスで7.04%の効率を達成しました.
結論:
- 新しいPA+ベースのRPとSLペロブスキットは,異なる電子構造とアニゾトロプ的特性を有しています.
- 太陽電池のような光電子装置に適しており,有望な効率性を示しています.
- SL構造は,光反応性ではないが,ユニークな1D電子特性を提供する.
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