合成,電子構造,分子包装/形質進化,純粋なオリゴ/ポリ (アルキルチオフェン) のキャリアモビリティ
Lei Zhang1, Nicholas S Colella, Feng Liu
1Department of Polymer Science and Engineering, Conte Research Center, University of Massachusetts, Amherst, Massachusetts 01003, USA.
Journal of the American Chemical Society
|December 13, 2012
まとめ
モノ分散結合オリゴチオフェンは,分子量だけでなく,結晶性および結晶の方向性によって引き起こされる,鎖の長さが減少するにつれて,電荷輸送の改善を示します. これはオリゴチオフェン半導体の理解を前進させる.
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
- 固体物理学 固体物理学とは
背景:
- モノ分散結合オリゴチオフェンは,ポリ分散ポリマーの重要なモデルシステムである.
- 独特の光学,光電子,電荷輸送特性を有しています.
研究 の 目的:
- モノ分散オリゴチオフェンを6つのディドデシル四四チオフェン (DDQT) 単位まで合成し,特徴づけます.
- 電子構造,分子包装,形態学,および電荷輸送を調査する.
- これらの性質を結合長と分子量と関連付けます.
主な方法:
- 異なるDDQTの繰り返し単位でオリゴチオフェンの合成.
- 分子構成と包装のためのX線結晶構造分析.
- 牧草の発生率 薄膜形態学のX線散射.
- 充電輸送の測定 (例えば,移動性).
主要な成果:
- 電子構造は,効果的な結合長さで,ポリ ((3,3"-ディドデシル-クォーターチオフェン) (PQT-12) に収束する.
- オリゴチオフェンは,ステリック障害を最小限に抑えるために,シンコンフォーメーションと曲がったアルキル鎖を示した.
- 形態学は,小分子型からポリマー型に進化し,有効結合長に近いパッキングに発展した.
- 鎖の長さの減少に伴い,荷载体の移動性が増加した.
結論:
- キャリアの移動性は,主に結晶性や結晶粒子の誤方向性によって支配され,分子量だけではありません.
- 結晶性と平面内向きの最適化は,低分子量オリゴチオフェンの移動性を高めるための鍵です.
- オリゴチオフェン半導体における結合長,分子包装,および電荷輸送の間の基本的なリンクを確立した.
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