Realizing loss-less charge separation at donor:acceptor interface

2023 Fiscal Year Final Research Report

• Project/Area Number: 21H02012
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 35030:Organic functional materials-related
• Research Institution: The University of Tokyo (2023); Kyoto University (2021-2022)
• Principal Investigator: Tamai Yasunari 東京大学, 大学院新領域創成科学研究科, 准教授 (30794268)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 励起子 / 電荷 / エネルギー移動 / 電荷移動 / 電荷再結合 / 高速分光

Outline of Final Research Achievements

We performed transient absorption measurements for organic solar cells consisting of PM6 and Y6. We found that after hole transfer from Y6 to PM6, we observed slow yet efficient spatial charge dissociation on a time scale of picoseconds. Based on temperature-dependence measurements, we found that this slow yet efficient free charge generation is driven by downhill energy relaxation of charges through the energy cascade generated near the interfaces.

Free Research Field

光物理化学

Academic Significance and Societal Importance of the Research Achievements

次世代の太陽電池として期待されている有機薄膜太陽電池の光電変換メカニズムを明らかにした。本研究成果は有機薄膜太陽電池のさらなる高効率化を促進するとともに、電荷分離・再結合を扱う広範な光物理・光化学分野の基礎的知見となる。