Development of Monolayers with Aggregation-Induced Emission for Transparent Luminescent Materials

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14499
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 28030:Nanomaterials-related
• Research Institution: Tokyo University of Technology
• Principal Investigator: Iritani Kohei 東京工科大学, 工学部, 助教 (60815124)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 凝集誘起発光 / 単分子膜 / 気液界面 / 両親媒性分子 / テトラフェニルエチレン / 透明発光体

Outline of Final Research Achievements

In order to form a luminescent monolayer at the air/water interface, a tetraphenylethylene (TPE) derivative with a hydrophilic group was synthesized. Using a Langmuir-Blodgett (LB) trough, a fluorescent thin film was successfully constructed. AFM observations after transfer to a solid substrate revealed that the thin film was uniform and had a monolayer thickness. In the case of TPE with alkyl groups, a thermal-stable film was be obtained due to repulsion between the alkyl groups. Furthermore, a film was formed in the same manner using a molecule in which the π-conjugated core of TPE was extended. Although no change was observed in the emission wavelength, it was found that the film-forming ability was improved by increasing the hydrophilicity of the hydrophilic group. These results are significant and will be of great help in designing molecules that construct luminescent monolayers.

Free Research Field

有機化学、表面化学、超分子化学

Academic Significance and Societal Importance of the Research Achievements

本研究では、凝集誘起発光性分子を用いた単分子膜を構築し、その発光波長を制御することを目的とする。従来の透明蛍光体の製法は、蛍光物質の微粒子化やレアメタルを用いる方法があるが、微粒子化が困難であることや原料が高価であることなどの課題があった。これに対して、本研究では安価かつ軽量性やフレキシブル性を維持した透明発光体の形成が可能である。さらに単分子膜という有機化合物の使用量を低減できるサステイナブルな材料という側面もあり、大きな社会的意義がある。また、これまでに積極的に発光性単分子膜を作製した例はなく、二次元的な膜構造に起因する物質の発光挙動を解明することは学術的にも意義があると言える。