聯苯雙偶極咔唑與聯苯氟衍生物之合成、性質探討及其在藍色磷光有機發光二極體之應用

Synthesis and Characterization of Carbazole-containing Bipolar Biphenyl and Fluoride-containing Biphenyl Derivatives and Applications in Blue Phosphorescent Organic Light Emitting Diodes

林坤賜(Kun-Zih Lin)

指導教授 ： 梁文傑

國立臺灣大學/理學院/化學研究所/碩士(2014年)

https://doi.org/10.6342/NTU.2014.10896

摘要

本篇論文中以聯苯為結構中心，分別在其2,2’位置接上咔唑基團與不同拉電子基 (丁腈、噁二唑、三氮唑、苯并咪唑)，合成一系列雙偶極咔唑化合物3、7、8、9，針對不同拉電子基分別比較其物理、光物理與電化學性質，觀察討論基團間可能的交互作用，並預計作為藍色磷光有機發光二極體(PhOLED)元件的主發光體；另外將咔唑基團置換為具有強拉電子性的氟原子，合成化合物13、14，目的為設計具有電子傳導性質的主發光體抑或是電子傳輸材料，透過能量轉移實驗以及其他化學性質的測量結果，我們選擇化合物7、8、9作為主發光體，搭配藍色磷光發光材料:雙(4,6-二氟苯基吡啶- N,C2]吡啶甲醯合銥(FIrpic)，製成有機發光二極體元件，三者未進行優化前最大發光效率均有39 cd/A以上，其中以化合物7摻混15 wt%的FIrpic表現最佳，以電流密度50 mA/cm2時的操作電壓9.33 V為驅動電壓，最大亮度6289 cd/m2，操作電壓4V時最大發光效率可達43.96 cd/A，最大發光功率為34.53 lm/W，最大外部量子效率18.50 %。

關鍵字

有機發光二極體 ； 咔唑 ； 丁腈 ； 噁二唑 ； 三氮唑 ； 苯并咪唑 ； 雙偶極 ； 主發光體 ； 氟

並列摘要

We synthesized a series of bipolar compounds containing carbazole group with biphenyl structure (compound 3, 7, 8 and 9), the carbazole group and electron-withdrawing moieties (nitrile, oxadiazole, triazole, and benzimidazole) were placed at the 2,2’ position of biphenyl structure, respectively. We will discuss the properties and possible interaction between carbazole and withdrawing moieties of these compounds through measuring photophysical and electrochemical properties for the purpose of application as host materials of blue phosphorescent light emitting diode (PHOLED).
The other side, we replaced carbazole group with fluorine atom which has strong electron withdrawing ability (compounds 13 and 14) for potential application in materials of host with electron-transporting ability or as electron transporting materials.
After the experiments of measuring energy transfer efficiency and other properties, we chose compounds 7, 8, and 9 for the test of blue PHOLED devices doped with FIrpic. All of them had current efficiency higher than 39 cd/A before optimization. Device of compound 7 doped with 15 wt% FIrpic had the best performance, with turn-on voltage 9.33 V at current density 50 mA/cm 2, max luminance 6289 cd/m2, max current efficiency43.96 cd/A at applied voltage 4 V, power efficiency 34.53 lm/W, external quantum efficiency 18.50 %.

並列關鍵字

OLED ； carbazole ； nitrile ； oxadiazole ； triazole ； benzimidazole ； bipolar ； host ； fluorine

參考文獻

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