非結合基ポリマーにおける電荷輸送の分子設計特性
Ying Tan1, Nicholas C Casetti1, Bryan W Boudouris1,2
1Charles D. Davidson School of Chemical Engineering, Purdue University, 480 Stadium Avenue, West Lafayette, Indiana 47907, United States.
Journal of the American Chemical Society
|July 19, 2021
まとめ
オープンシェルララジカルグループを使用する新しい導電ポリマーは,処理と安定性の利点を提供します. この研究では,TEMPOラジカルの高い再構成エネルギーによる電荷輸送を制限し,新しい化学反応が性能を改善することを示唆しています.
科学分野:
- 材料科学
- オーガニック電子
- ポリマー化学
背景:
- オープンシェルララジカル部分を持つ導体ポリマーは,従来のドープ付き結合ポリマーよりも処理,安定性,光学上の利点を提供します.
- 現在の急流導体は主に (2,2,6,6-テトラメチルピペリジン-1-イル) オキシル (TEMPO) を使用しており,最終的な電荷輸送限界と物質の欠陥の理解を制限している.
研究 の 目的:
- 放射性導体のための様々なオープンシェル化学の電荷伝送特性を調査する.
- TEMPOに対する様々な化学基質の性能を比較する.
- 料金輸送を制限する要因を特定し,改善のための戦略を探求する.
主な方法:
- 密度関数理論 (DFT) を利用して,p型,n型,アンビポラオープンシェル化学における電荷移転を研究した.
- 再構成エネルギーと電荷の局所化効果を分析した.
- ラジカル-ラジカル方向と分子間相互作用による電荷移転の依存性をマッピングした.
主要な成果:
- TEMPOは高い再編成エネルギーと強い電荷局所化を示し,より局外化されたオープンシェル種と比較して電荷転送能力を制限しています.
- 望ましい分子間形状と,すべての研究された化学物体間の電荷移転に最適な形状との間に,重大な不一致がある.
- 誘導相互作用を通じて形状を操作することによって,電荷輸送を強化する機会を特定した.
結論:
- TEMPOはすべての根導体を代表するものではありません.代替化学は優越した電荷輸送の可能性を提供します.
- 分子間相互作用と根の形状は,電荷輸送効率に重大な影響を及ぼします.
- 放射性ポリマーの戦略的設計は,電荷輸送を大幅に改善するために,方向相互作用を利用することができます.
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