分子質量ヘテロ結合物質における光誘導電荷生成
Loren G Kaake1, Jacek J Jasieniak, Ronald C Bakus
1Center for Polymers and Organic Solids, University of California-Santa Barbara, Santa Barbara, California 93106, United States. lkaake@physics.ucsb.edu
Journal of the American Chemical Society
|November 8, 2012
まとめ
オーガニックの太陽光発電では,興奮状態のデロカライゼーションにより,電荷キャリアは100フェムト秒以内に生成されます. 分子とポリマーの大量ヘテロ結合の両方で観察されるこの超高速プロセスは,デバイスの効率を改善する鍵です.
科学分野:
- オーガニック・エレクトロニクス
- フォトボルトイカは,太陽光発電の
- スペクトル顕微鏡検査です.
背景:
- 充電生成の理解は,有機光伏 (OPV) 装置の効率を高めるために非常に重要です.
- 広範な研究にもかかわらず,OPVにおける電荷生成と再結合のための完全なモデルはまだ開発中です.
研究 の 目的:
- 超高速電荷光生成と再結合ダイナミクスを,高性能有機光伏の大量ヘテロジャンクション (BHJ) 混合物で調査する.
- 溶液加工分子BHJとポリマーベースのBHJ材料におけるこれらのダイナミクスを比較する.
主な方法:
- 超高速短時間吸収スペクトロスコーピー.
- 極化アニソトロピーの測定. 極化アニソトロピーの測定.
- 溶液処理された分子BHJの純薄膜の研究.
主要な成果:
- 大半の電荷キャリアは,分子およびポリマーBHJの両方で<100 fsで生成されます.
- 興奮状態のデロカライゼーションは,超高速の電荷移転のメカニズムとして識別されます.
- エクシトンのヘテロジャンクションへの拡散は,1~500 ps.の間で観察されました.
- 純粋な分子フィルムは,分子刺激子によって支配される迅速な非局所化された電荷生成 (t < 100 fs) を示しています.
結論:
- 超高速充電生成 (<100 fs) は,高性能な有機BHJの重要な特徴であり,興奮状態の移転によって駆動されます.
- エクシトンの拡散は,より長い時間スケールで役割を果たします.
- 発見は,より効率的な有機光伏材料の設計のための洞察を提供します.
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