Development of highly sensitive transient-absorption measuring system for kinetic studies in organic electroluminescent devices
| Project/Area Number |
17K05746
|
|---|
| Research Category |
Grant-in-Aid for Scientific Research (C)
|
| Allocation Type | Multi-year Fund |
|---|
| Section | 一般 |
|---|
| Research Field |
Physical chemistry
|
|---|
| Research Institution | University of Toyama |
|---|
Principal Investigator |
Nozaki Koichi 富山大学, 学術研究部理学系, 教授 (20212128)
|
|---|
| Project Period (FY) |
2017-04-01 – 2020-03-31
|
| Project Status |
Completed (Fiscal Year 2019)
|
| Budget Amount *help |
¥4,680,000 (Direct Cost: ¥3,600,000、Indirect Cost: ¥1,080,000)
Fiscal Year 2019: ¥910,000 (Direct Cost: ¥700,000、Indirect Cost: ¥210,000)
Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2017: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
|
|---|
| Keywords | 有機薄膜 / 過渡吸収スペクトル / アップコンバージョン / イリジウム錯体 / 拡散速度 / 三重項消滅 / 過渡吸収 / 拡散定数 / 過渡吸収測定 |
|---|
| Outline of Final Research Achievements |
A measurement system of high-sensitivity transient absorption spectra with nanosecond time resolution was developed for observation of non-emissive species in thin-layer organic films. fac-Ir(ppy)3, well-known as a green emissive OLED phosphor, exhibits yellow phosphorescence in neat films depending on their formation conditions. While the yellow emissive state has been ascribed to an excimer of Ir(ppy)3, high-sensitivity transient absorption spectra measurements revealed that the yellow emission originated from impurities in the films.
While triplet-triplet annihilation-upconversion(TTA-UC) in solid-state films has attracted much attention recently, the improvement of TTA-UC efficiencies in DPA:PtOEP binary solids requires deep understandings of formation and decay dynamics of triplet species. Based on high-sensitivity transient absorption measurements for DPA:PtOEP binary solid films, the quantum yields of triplet energy transfer from PtOEP to DPA and TTA of DPA were evaluated.
|
| Academic Significance and Societal Importance of the Research Achievements |
本研究では，有機電界発光素子などで注目されている発光性有機薄膜中での三重項状態やイオン種などの非発光化学種の濃度や生成収率を直接観測するため，紫外～近赤外領域の超高感度ナノ秒時間分解過渡吸収測定装置を開発した。この方法により，薄膜中での三重項励起子の生成収率や減衰速度，三重項－三重項消滅のダイナミクスなど，これまでの発光分光法では観測できなかった非発光性の化学種についての量的，速度論的な情報を得ることが可能になった。さらに，非発光種のスペクトル観測が可能になることで，励起子のトラップする膜中の不純物についてのスペクトル情報が得られるようになり，素子の長寿命化に寄与できると期待できる。
|
Report
(4 results)
Research Products
(17 results)
