有機發光二極體 (Organic Light Emitting Diode, OLED) 是當今最受注目的平面顯示技術，應用在手機及電視等產品上，具有廣視角、高對比、高反應速率、可低溫操作等優點；而其節能、散熱快、光綫柔和等特性，具有角逐最佳照明技術的潛力；此外，可製作在柔性撓曲式電子基板的優勢，更增加OLED多元應用的可能性。
本研究使用一新穎主體材料 9,9’-[oxetane-3,3-diylbis(methylene)]bis[3-(2-methoxypyridin-3-yl)-9H-carbazole)] [DB6] 與磷光橘紅光染料 Tris(2-phenylquinoline)iridium(III) [Ir(2-phq)3] 製作高效橘紅光OLED，在亮度 100 cd/m2 時，元件的能量效率及電流效率分別是20.5 lm/W及21.9 cd/A，在亮度 1,000 cd/m2 時，元件的能量效率及電流效率分別是16.4 lm/W及22.1 cd/A。
使用材料DB6的高效率可歸因於：一、DB6有效的分散激子再結合區域，避免激子集中產生淬熄，二、主體材料DB6與客體材料Ir(2-phq)3具有良好的能量轉移。
進一步使用4,4’,4’’-Tris[phenyl(m-tolyl)amino]triphenylamine [m-MTDATA] 作為共主體添加，製備另一高效橘紅光OLED，在亮度 100 cd/m2 時，其能量效率及電流效率提升至 31.2 lm/W及 30.3 cd/A，提升幅度分別為 52% 及 38%，在亮度 1,000 cd/m2 時，其能量效率及電流效率提升至 16.8 lm/W及 23.7 cd/A，提升幅度分別為 2.4% 及 7.2%。
此共主體添加大幅改善了效率，可歸因於共主體m-MTDATA具有較電洞傳輸層淺的HOMO，使得電洞得以有效注入，降低元件操作電壓，進而提升效率。

Organic Light Emitting Diode (OLED) is nowadays the most popular flat-panel display technology used in mobile phones and TVs. It has several advantages such as wide viewing-angle, high contrast, fast response, and capability of low temperature operation. Furthermore, the properties of OLED like energy saving, fast heat dissipation, and soft light make it candidate to become best optimal lighting technology. In addition, OLED devices can be fabricated on flexible electronic substrates, which improves the possibility of OLED multi-applications.
This study used a novel host material 9,9'-[oxetane-3,3-diylbis(methylene)]bis[3-(2-methoxypyridin-3-yl)-9H-carbazole)] [DB6] and phosphorescent orange-red dyes Tris(2-phenylquinoline)iridium(III) [Ir(2-phq)3] to produce high-efficiency orange-red OLEDs. The power efficacy is 20.5 lm/W and the current efficacy is 21.9 cd/A at 100 cd/m2. The power efficacy is 16.4 lm/W and the current efficacy is 22.1 cd/A at 1,000 cd/m2.
The high efficacy can be ascribed to high efficiency energy transfer from DB6 to Ir(2-phq)3 and the effective dispersion of excitions which avoid quenching.
When 4,4',4''-Tris[phenyl(m-tolyl)amino]triphenylamine [m-MTDATA] was used as a co-host to prepare another high-efficiency orange-red OLED. The power efficacy is 31.2 lm/W and the current efficacy is 30.3 cd/A at 100 cd/m2, which are 52% and 38% higher than the device without the co-host respectively. The power efficacy is 16.8 lm/W and the current efficacy is 23.7 cd/A at 1,000 cd/m2, which are 2.4% and 7.2% higher than the device without the co-host respectively.
The great efficacy improvement can be ascribed to the co-host. It has a higher HOMO which provides effective hole injection that decreases the operating voltage and increases the power efficacy.

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