結合されたポリエレクトロライトにおける電荷移転状態のイオン誘発による形成
Justin M Hodgkiss1, Guoli Tu, Sebastian Albert-Seifried
1Cavendish Laboratory, Department of Physics, University of Cambridge, CB3 0HE, UK. justin.hodgkiss@vuw.ac.nz
Journal of the American Chemical Society
|June 2, 2009
まとめ
結合ポリマーフィルムのイオンは,電荷移転状態を作り,発光を消します. この研究は,時間解像度スペクトロスコピーを用いてこの現象を説明し,ポリマー光伏装置の洞察を提供しています.
科学分野:
- 材料科学 材料科学とは
- フォトフィジックスの光学
- ポリマー化学のポリマー化学について
背景:
- 結合ポリマーは,有機電子学の鍵となります.
- イオンを含むポリマーフィルムにおける光抑制は,既知の問題である.
- 消火メカニズムを理解することは,デバイスの最適化に不可欠です.
研究 の 目的:
- イオンを含有する結合ポリマーにおける光解消の背後にあるメカニズムを解明する.
- イオン誘発冷却における電荷移転状態 (CT) の役割を調査する.
- ポリマー光伏装置におけるイオン工学の可能性を調査する.
主な方法:
- 時間解像度光学スペクトルスコピー (光発光と一時吸収).
- F8BT.に基づいた特定の結合ポリエレクトロライト (CPE) の合成と特徴付け.
- 温度に依存する光発光測定.
主要な成果:
- CPEフィルムにおける光解消は,イオン安定化された電荷伝送状態に起因する.
- CT状態は赤にシフトし,長生きし,不動である.
- CT状態の形成の前に,イオン領域へのエキシトンのジャンプは熱的に活性化されます (E ((作用) = 28 meV).
- 光発光量子効率は,親ポリマーと比較して,ポリエレクトロリットの薄膜で著しく低下します.
結論:
- 負荷移転状態のイオン誘発の安定化は,結合ポリエレクトロライトにおける一般的なメカニズムである.
- この現象は,刺激ダイナミクスを制御するために活用することができます.
- ポリマー太陽電池の電荷分離インターフェースに向かってエクシトンの流れを誘導する可能性.
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