Solution-processed solar cell with a composite of inorganic colloidal quantum dots and organic singlet exciton fission molecules

2019 Fiscal Year Final Research Report

• Project/Area Number: 17H03103
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Organic and hybrid materials
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: Pu Yong-Jin 国立研究開発法人理化学研究所, 創発物性科学研究センター, チームリーダー (00350489)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Keywords: 量子ドット / 一重項励起子分裂 / 太陽電池

Outline of Final Research Achievements

Colloidal quantum dots of lead sulfide semiconductor were precisely synthesized, and their size and energy gap were finely controlled. Wide energy gap singlet exciton fission organic compounds having high energy level of lowest excited triplet state, which is important for high open circuit voltage, were designed and synthesized. One of compounds based on non-acene structure showed possibility of higher T1 of 1.38 eV than 1.2 eV of previously reported high T1 tetracene. In the applications for solar cells, control of alignment and packing of quantum dots are important for unique charge and exciton transport and confinement. Lead sulfide quantum dots with smaller size than 5 nm were synthesized, and their one-dimensional alignment was achieved by self-assembly method in solution.

Free Research Field

有機物理化学

Academic Significance and Societal Importance of the Research Achievements

有機一重項励起子分裂は、多重励起子生成プロセスとして極めて高い注目を集めているが、利用できるエネルギーが小さい(太陽電池では電圧が低い)ため、学術的な興味に留まっている。従来材料を大きく越える、高いエネルギー準位を有する有機一重項励起子分裂分子の設計・合成に成功した。また、球状な半導体量子ドットの二次元での配列制御は多く報告されているが、自発的に1次元に並べる事は極めて難しい。溶液中での自己集合プロセスにより、コロイド半導体量子ドットの1次元配列に成功した。様々なエネルギーデバイス、情報デバイスへの応用が期待される。