聯苯三氮唑衍生物之合成、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 triazole-Containing Biphenyl Derivatives and Application in Blue Phosphorescent Organic Light Emitting Diodes

陳乃菁(Nai-Jing Chen)

指導教授 ： 梁文傑

國立臺灣大學/理學院/化學研究所/碩士(2011年)

https://doi.org/10.6342/NTU.2011.00443

摘要

本篇論文合成了以聯苯為主體的三氮唑衍生物，並引入不同的取代基，由光化學、電化學討論其分子形狀及取代基效應所造成的影響。分子形狀會影響其光物理性質及熱穩定性，由X射線單晶繞射圖可知，此剪刀狀分子會造成分子的共軛被破壞，且其非共平面的結構也會使分子不易形成分子間的推疊，因此具有良好的熱穩定性。由電化學實驗可知，推電子的取代基對還原電位影響很小，還原反應發生於三氮唑環，因化合物5-8的三氮唑環與氮上的苯環為非共平面結構，其共軛被破壞，非定域化於苯環之自由基陰離子，幾乎可被忽略。最後，取化合物5-8當作主發光體材料，混摻藍光客發光體材料-雙（4, 6-二氟苯基吡啶-N,C2）吡啶甲基合銥應用於製作藍色磷光有機發光二極體之元件，其中以化合物7作為主發光體材料的元件效率最好，發光層以化合物7為主發光體混摻客發光體FIrpic，在最佳化的條件下，其最大發光效率可達44.3 cd/A，且最大亮度可達2123 cd/m2。

關鍵字

OLED ； 主發光體材料 ； 三氮唑 ； 聯苯 ； 發光二極體

並列摘要

In this thesis, 2,2’-bis(1,5-diphenyl-1,2,4-triazol)biphenyl derivatives were successfully prepared. These compounds possess scissor-like conformations which were evidenced by using the spectroscopic and electrochemical methods, as well as by X-ray crystallography. The presence of the ample conformational variations influences their photoluminescence and morphological stability: (1) the scissor-like structures would breakdown the intramolecular pi-conjugation of the molecule, (2) The non-coplanar structure would also hamper the intermolecular stacking, prohibiting the compounds from crystallization and therefore increasing the thermal stability of their amorphous film structure. Two reduction waves by cyclic voltammetry were observed for each compound, indicating that both of the triazole units could be smoothly reduced. Although the reduction potential difference is small, the presence of the difference clearly indicates that through-space electronic interactions are present between the two triazole units. The electronic effects arising from the substituent of terminal phenyl units on the triazole reductions are small. These results suggest that the anionic sites are mainly localized at the triazole units. Delocalization of the negative charges onto the terminal phenyl rings is almost negligible. Organic light emitting diodes (OLED) with 2,2’-bis(1,5-diphenyl-1,2,4-triazol)biphenyl as the host matrix for FIrpic were successfully prepared. Under the best conditions, the OLED exhibited luminance efficiency of 44.3 cd/A with the maximum brightness of 2123 cd/m2.

並列關鍵字

OLED ； 1, 2, 4-trazole ； host ； biphenyl ； emitting diodes

參考文獻

1. 陳金鑫、黃孝文，有機電激發光材料與元件 2005.

55. Chiu, T. L.; Lee, P. Y. ; Lee, J. H.; Hsiao, C. H.; Leung, M. -k.; Lee, C. C. ;Chen, C. Y.; Yang, C. C. Appl. Phys. Lett. 2011, 109, 084520.

57. Li, Z. H.; Wong, M. K.; Fukutani, H., Tao, Y. Org. Lett. 2006, 8, 4271.

27. Mason, M. G.; Hung, L. S.; Tang, C. W.; Lee, S. T.; Wong, K. W.; Wang, M. J. Appl. Phys. 1999, 86, 1688.

17. （a） Tang, C. W.; Vanslyke, S. A.; Chen, C. H. J. Appl. Phys. 1989, 65, 3610.（b） Era, M.; Adachi, C.; Tsutsui, T.; Saito, S. Chem. Phys. Lett. 1991, 178, 488.