横鎖方向の π スタッキング幾何学によって選択された電子や穴を運ぶ性質: 液晶溶融メタルポルフィリンジマー
Tsuneaki Sakurai1, Kentaro Tashiro, Yoshihito Honsho
1School of Engineering, The University of Tokyo, 7-3-1 Hongo, Tokyo 113-8656, Japan.
Journal of the American Chemical Society
|April 12, 2011
まとめ
新しい液晶半導体は,溶融したポルフィリン二重体の銅複合体から合成されました. これらの材料は,サイドチェーン構造に基づいて,異なるn型およびp型半導体行動を示す.
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
- 超分子化学 超分子化学
背景:
- 液晶 (LC) 半導体は,電子アプリケーションにユニークな自己組み立て性能を提供します.
- ポルフィリンジメは,その拡張されたπ結合により,有望な電気活性コアです.
研究 の 目的:
- 合わせたサイドチェーンの銅ポルフィリンジマーに基づく新しい液晶半導体を合成する.
- サイドチェーンアーキテクチャがこれらの材料の自己組み立てと充電輸送特性に及ぼす影響を調査する.
主な方法:
- ドデシルとセミフルオアルキルのサイドチェーン (PP(ヘテロ)) とセミフルオアルキルのサイドチェーン (PP(ホモ)) を含む溶融したポルフィリン二元銅複合体の合成.
- これらの複合体によって形成される液晶メソフェスの特徴.
- 充電輸送特性を評価するために,飛行時間条件下で一時的な光電流の測定.
主要な成果:
- PP (ヘテロ) は長方形柱状のLCメソフェーズを形成し,PP (ホモ) は正方形柱状のLCメソフェーズを形成した.
- 同じような溶液状態の電子特性にもかかわらず,PP (ヘテロ) はn型半導体行動を示した.
- PP(homo) は,LC状態でp型半導体行動を示した.
結論:
- ポルフィリンベースのLC半導体のサイドチェーンエンジニアリングは,その自己組み立てと充電輸送特性を正確に制御することができます.
- 異なるLCメソフェーズにおける異なるスタッキング幾何学は,補完的なn型およびp型半導体特性につながります.
- これらの発見は,PorphyrinベースのLC素材を使用して,アンビポラーまたは補完的な論理回路を開発するための道を開きます.
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