新型熱活化延遲螢光發光體的光物理性質和電致發光研究

Abstract

近年來，有機發光二極體（OLED）已成為顯示和照明應用的重要技術。隨著OLED技術的不斷發展，器件效率，器件可靠性和製造成本等參數對於該領域的研究至關重要。在本論文中，我們通過分析光物理和電致發光特性以及利用這些材料的器件架構，深入研究了基於熱活化型延遲螢光（TADF）的新型有機發光材料。 在本論文的第一部分，我們研究了基於Donor-Acceptor（D-A）分子結構和有電子受體喹喔啉部分的TADF材料的光物理和電致發光性質。我們的研究表明它們是高效的TADF材料。值得注意的是，當與二氫吖啶供體單元配對時，該材料同時表現出100%的光致發光量子產率（PLQY）和水平取向的發光偶極子。它們可用於製造高效的橙紅色OLED，外部量子效率（EQE）高達23.2％。 在本論文的第二部分，我們繼續研究基於吖啶供體單元和不同受體單方的TADF材料的光物理和電致發光特性，特別是9,9-dimethyl-9,10-dihydroacridine （DMAC）和10H-spiro[acridine-9,9'-fluorene（SpiroAc）。我們的研究表明，這些材料還可以具有明顯高的PLQY和水平取向的發射偶極子。它們可用於製造高效的綠色OLED，錄光元件EQE可高達33.7％，藍色OLED的EQE可高達14％。

In recent years, organic light-emitting diodes (OLEDs) have become a significant technology for display and lighting applications. As the OLED technology continues to reach more prominence, parameters such as device efficiency, device reliability, and manufacturing cost are critical to consider in this research field. In this thesis, we focused on the investigation of novel organic light-emitting materials based on thermally activated delayed fluorescence (TADF) through analysis of photophysical and electroluminescence characteristics. In the first section of this thesis, we investigated photophysical and electroluminescent properties of organic materials based on a donor-acceptor (D-A) molecular architecture with an electron-accepting quinoxaline moiety. Our studies indicate they are highly efficient TADF materials. Notably, when paired with a dihydroacidine donor unit, the material simultaneously exhibits unitary photoluminescence quantum yield (PLQY) and horizontally oriented emitting dipoles. They can be utilized to fabricate highly efficient orange-red OLEDs with an external quantum efficiency (EQE) up to 23.2%. In the second section of this thesis, we continued our investigation of photophysical and electroluminescent characteristics for TADF materials based on acridine donor units, specifically 9,9-dimethyl-9,10-dihydroacridine (DMAC) and 10H-spiro[acridine-9,9'-fluorene (SpiroAc), and different acceptor units. Our studies indicate that these materials can also possess noticeably high PLQY and horizontally oriented emitting dipoles. Therefore, they can be used to fabricate efficient green OLEDs with EQEs up to 33.7% and blue OLEDs with EQEs up to 14%.