短鎖チアゾロチアゾル-チオフェン共ポリマーにおける高ラメラー順序と無形型のPIネットワークは,高移動性をもたらします
Itaru Osaka1, Rui Zhang, Geneviève Sauvé
1Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA.
Journal of the American Chemical Society
|February 3, 2009
まとめ
半導体ポリマーの高いキャリアモビリティは,長いバックボーンや結晶のサイドチェーンなしで達成できます. 新しいポリチオフェン型のシステムは,構造が乱れているにもかかわらず,優れた電子性能を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- オーガニック・エレクトロニクス
- ポリマーサイエンスの科学
背景:
- ポリー ((アルキルチオフェン) は,有機電子のための半導体ポリマーとして広く研究されています.
- キャリアのモビリティは,電子性能にとって極めて重要であり,しばしば,骨幹の長さやサイドチェーンの結晶性を増加させることで強化されます.
- 以前の研究によると,高い結晶度と長い背骨は,優れた電子性能のために必要である.
研究 の 目的:
- シアゾロチアゾール単位 (PTzQT) のチオフェンベースの半導体ポリマーの電子性能を調査する.
- 長い結合した脊椎と高結晶の横鎖が,高キャリアの移動性にとって不可欠であるかどうかを判断する.
- 物質構造,無秩序,および電荷輸送特性との関係を探求する.
主な方法:
- チオフェンベースの半導体ポリマー (PTzQT) の合成.
- 航空母艦の移動性を測定する.
- 結晶性と分子包装を評価するために,熱分析とX線散射を行います.
- 原子力顕微鏡 (AFM) で,ナノスケールの形状を分析する.
主要な成果:
- PTzQTポリマーは,高いキャリアモビリティ (約. 0.3cm2/Vs) にもかかわらず,低分子量と抑制されたサイドチェーン結晶性.
- 材料は,ナノスケールで非常に乱雑な性質を示し,無形のような上部構造を形成しました.
- キャリアの移動性は,アルキル側鎖の長さとともに増加し,表面の粗さ特性と相関する.
結論:
- ポリチオフェン型のシステムでは,長い結合した背骨や重要なサイドチェーンの結晶性なしに,高キャリアの移動性が達成可能である.
- 材料の乱れとナノスケールの表面の粗さはこのシステムにおける電荷輸送を制御する上で重要な役割を果たします.
- これらの発見は,有機半導体の流動性を高めるための従来の戦略に挑戦しています.
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