サイクロペンタ[b]チオピランを基にした角形ヘテロアレンの結晶工学
Yanjun Qiao1, Longfei Yang1, Jiangyu Zhu1
1Department of Materials Science, Fudan University, Shanghai 200433, China.
Journal of the American Chemical Society
|July 16, 2021
まとめ
サイクロペンタ[b]チオピランを基にした有機半導体が合成された. アルキル鎖を修正し,塩素原子を追加することで,フィールド効果トランジスタの分子包装と電荷キャリアの移動性が改善された.
科学分野:
- オーガニックの電子機器
- 材料科学
- 半導体物理学
背景:
- サイクロペンタ[b]チオピランはベンゾ[b]チオフェンの同位体であり,アズレンの同位電子である.
- オーガニック半導体は,フィールドエフェクトトランジスタ (FET) のような高度な電子機器の開発に不可欠です.
- 溶解性有機半導体には 精密な分子設計が求められます
研究 の 目的:
- サイクロペンタ[b]チオピランを基に新しい角形ヘテロアレンを合成する.
- アルキル鎖長と塩素置換がこれらのヘテロアーレンの性質に及ぼす影響を調査する.
- オーガニック・フィールド・エフェクト・トランジスタ (OFET) の分子構造,結晶包装,および電荷輸送特性を相関させる.
主な方法:
- サイクロペンタ[b]チオピラン誘導体の2つのシリーズの合成:C-SS (異なるアルキル鎖長) とC-SS-Cl (異なる塩素置換位置).
- 近赤外線吸収と最高占成分子軌道 (HOMO) エネルギーレベルを含む光物理学的および電気化学的性質の特徴.
- 単結晶X線微分法を用いた分子包装構造の分析.
- フィールド・エフェクト・トランジスタにおける電荷キャリアの移動性を測定する.
主要な成果:
- 7つのS-ヘテロアレンが合成され,同様の光物理および電気化学的性質を示した.
- 分子包装構造は,同一のπ結合骨格にもかかわらず,電荷キャリアの移動性に大きく影響した.
- C-SSシリーズは,中程度のアルキル鎖の長さで最大1.1cm2/V·sの穴の移動性を達成しました.
- 塩素原子を組み込むことで,分子間S·H接触と対平面間の距離が短縮される.
- 結晶化溶媒は結晶包装に影響を与え,クロロベンゼンから結晶化されたC-SS-Clは最大2.7cm2/V·sの穴移動性を示した.
結論:
- 塩素原子の導入は,有機半導体における結晶構造の調節と電荷輸送の実行可能な戦略です.
- ペンダントアルキル鎖と塩素化位置の分子工学は,OFETにおける電荷キャリアの移動性を最適化するための鍵です.
- この研究は,有機電子材料の性能を決定する際の分子間相互作用と結晶の重要な役割を強調しています.
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