蒸気で堆積した小分子/フルレン有機太陽電池の電荷キャリアダイナミクス
Angela Y Chang1, Yi-Hong Chen, Hao-Wu Lin
1Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA.
Journal of the American Chemical Society
|May 31, 2013
まとめ
小分子有機太陽電池 (SMOSC) は5.81%の効率を達成しています. 充電分離は ~100 fsで起こりますが,再結合は性能を制限し,形態学的改善がより良い太陽光発電の鍵であることを示唆しています.
科学分野:
- マテリアルサイエンス 材料科学
- 光伏は,太陽光発電である.
- オーガニック・エレクトロニクス
背景:
- 小分子有機太陽電池 (SMOSC) は,有望な太陽光発電の可能性を秘めています.
- SMOSCの性能を左右する光物理学に関する研究は限られている.
- 充電ダイナミクスを理解することは,デバイスの効率を最適化するために不可欠です.
研究 の 目的:
- 特定のSMOSC材料における電荷分離と再結合の時間スケールと効率を調査する.
- 光物理学的プロセスを材料のパワー変換効率と相関させるため.
- デバイスの性能を制限する要因を特定するために.
主な方法:
- DTDCTB (ドナー) とC60/C70 (受容体) の蒸気沈殿した薄膜の製造.
- 超高速電荷のダイナミクスを探査するために,一時的吸収スペクトロスコーピー.
- 時間解像度光発光 (trPL) は,電荷キャリアの寿命と分離効率を決定する.
主要な成果:
- 充電分離は,約100フェムト秒 (fs) 以内に急速に発生します.
- チャージ再結合は,サブナノ秒 (sub-ns) とナノ秒 (ns) の時間スケールで起こります.
- きちんとしたフィルムにおけるドナー電子孔ペアの寿命は,約33ピコ秒 (ps) です.
- ~20%のドナーは,形態学的要因のために混合フィルムで電荷分離を達成できない.
結論:
- この研究は,高効率のSMOSCにおける重要な電荷分離と再結合のダイナミクスを明らかにしています.
- 形態学的特徴,特にドナーが豊富な地域は,効率的な電荷分離を妨げます.
- 形状の最適化は,SMOSCの電力変換効率をさらに高めるための実行可能な戦略です.
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