Total Landscape of Charge Carrier Transport on Conjugated Polymer Backbones

2021 Fiscal Year Final Research Report

• Project/Area Number: 18H03918
• Research Category: Grant-in-Aid for Scientific Research (A)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Medium-sized Section 35:Polymers, organic materials, and related fields
• Research Institution: Kyoto University
• Principal Investigator: Seki Shu 京都大学, 工学研究科, 教授 (30273709)
• Co-Investigator(Kenkyū-buntansha): 櫻井 庸明 京都大学, 工学研究科, 助教 (50632907) ; 酒巻 大輔 大阪府立大学, 理学(系)研究科(研究院), 助教 (60722741)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 界面 / 共役高分子 / 電子輸送 / 光エネルギー / 水素発生 / ２次元 / COF / ポリアセチレン

Outline of Final Research Achievements

We have developed three game-changing spectroscopic technique for local charge carrier mobility at the interfaces of conjugated polymers and electronic materials: TRMC@Interfaces, TRMC@Transformation, and TRMC-Impedance Combined techniques. Along with the above three key techniques, the local charge carrier mobility at interfaces has been well determined for polythiophenes, PPE, and polyacetylenes on insulating electronic materials, exhibiting efficient conductive channels in contrast to their bulk states, reflecting their unique aggregated structures on 2D planar surfaces. We have also developed a series of 2D conjugated polymers with unique electronic conjugation over the skeletons, and confirmed the highly mobile electrons by the above spectroscopic techniques. The mobile charges have been well implemented as the reactive transient species in photo-induced oxidation-reduction of water molecules, suggesting high photo-catalytic activities in hydrogen evolution reactions.

Free Research Field

高分子化学

Academic Significance and Societal Importance of the Research Achievements

本研究で開発した計測法はいずれも、界面における電子伝導特性を非接触・非破壊で定量分析する手法として，これまで存在しなかった“測れなかったものを測る”計測法でもある．特に，骨格自由度の大きな共役高分子が界面においてどのような凝集構造・骨格構造を取り，その電子共役系が電子輸送に対しどこまで有効に働くか，という共役高分子を用いた電子材料開発に欠かせない計測法を提供する．外場による高分子骨格の変調構造・界面における共役骨格の微視的構造因子と電荷輸送特性の関連を今後さらに回折手法と組み合わせて定量評価することで，理想的な界面構造は何か？という大きな課題に決定的な解を与えられると考えている．