有機光伏材料で観察された電荷の局所化の起源
James E Johns1, Eric A Muller, Jean M J Frechet
1Department of Chemistry, University of California Berkeley, Berkeley, California 94720, United States.
Journal of the American Chemical Society
|October 22, 2010
まとめ
オーガニック半導体のアルキルサイドチェーンは,電荷を局所化し,電荷の移動を阻害する. この発見は,有機電子と太陽光発電の性能を改善するためにアルキル基を避けることを示唆しています.
科学分野:
- オーガニック・エレクトロニクス
- マテリアルサイエンス 材料科学
- フォトヴォルタイク (光伏) について
背景:
- オーガニック・エレクトロニクスは,低電荷のモビリティと,形態学/分子学的効果の解き放つという課題に直面しています.
- アルキルサイドチェーンは,加工と効率を向上させるため,有機半導体で一般的ですが,電荷輸送への影響は不明です.
研究 の 目的:
- 有機半導体における電荷輸送特性に対するアルキル側鎖の影響を調査する.
- 電荷の局所化と移動性におけるアルキル置換剤の役割を決定する.
主な方法:
- 2フォトンの光放出スペクトロスコーピーを利用しました.
- セキシチオフェン (アルキル鎖なし) とダイエキシル-セキシチオフェン (アルキル鎖付き) での電荷輸送を研究した.
主要な成果:
- 炭化水素のサイドチェーンが230フェムト秒以内に電荷の局所化を起こすことが判明しました.
- アルキル置換剤と電荷の移動性の低下との直接的な関連が示された.
結論:
- アルキル側鎖は,有機半導体における電荷輸送を阻害する.
- 有機光伏および電子機器の性能を改善するために,アルキルリガンドよりも代替化学グループが推奨されています.
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