ポリマー:フルレレンの電荷生成を詳しく見ると,マイクロ構造制御と融合する
Mariateresa Scarongella1, Jelissa De Jonghe-Risse, Ester Buchaca-Domingo
1Institute of Chemical Sciences & Engineering, Ecole Polytechnique Fédérale de Lausanne (EPFL) , SB ISIC GR-MO, Station 6, CH-1015 Lausanne, Switzerland.
Journal of the American Chemical Society
|February 5, 2015
まとめ
ポリマー:フルレンの混合物における電荷生成は,エキソン拡散によって制限されるが,混合した領域では加速される. 混合ドメインから整然としたドメインへの超高速ホールの移行は,pBTTT:PCBMシステムにおける再結合を防止します.
科学分野:
- マテリアルサイエンス 材料科学
- フォトボルトイカは,太陽光発電
- オーガニック・エレクトロニクス
背景:
- ポリマー:フラーレン混合物は,有機太陽電池にとって極めて重要です.
- 充電生成メカニズムを理解することは,デバイスの効率を向上させるための鍵です.
- 添加物によるマイクロ構造制御は,ブレンドの性能に影響します.
研究 の 目的:
- pBTTTにおける電荷生成メカニズムを解明するため:PCBM混合物.
- 微細構造と領域形態学の役割を調査する.
- エクシトン拡散と電荷分離のダイナミクスを理解する.
主な方法:
- 超高速短時間吸収スペクトロスコーピー
- 電気吸収 (スターク効果) スペクトロスコピー
- 光アップ変換スペクトロスコピー
- 脂肪酸メチルエステル添加物による加工
主要な成果:
- フェーズ純粋領域におけるエキシトン拡散は,電荷伝送率を制限する.
- 素早い電荷分離は,分子的に混合された領域 (共結晶相) で発生する.
- ニートドメインは,双子の再結合を防ぐために不可欠です.
- 混合ドメインから整然としたドメインへのサブピコ秒ホールの移行の直接可視化.
結論:
- 効率的な電荷生成と分離には,分子融合と整然とした領域が不可欠である.
- 超高速の穴の輸送は,エネルギーカスケードと高い局所移動によって促進されます.
- 微細構造の制御は,有機光伏の性能を最適化するために不可欠です.
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