臺灣博碩士論文加值系統

本篇論文研究包含兩部分。在本篇論文的第一部分，我們使用台大化學所梁文傑實驗室所提供的咔唑與苯並咪唑碳氮連接之雙極性衍生物9-(2-(2-phenyl-1H-benzo[d]imidazol-1-yl)phenyl)-9H-carbazole (A-o-CBZBIZ) 、 和9-(3-(9H-carbazol-9-yl)-2-(2-phenyl-1H-benzo[d]imidazol-1-yl)phenyl)-9H-carbazole (A-dio-CBZBIZ)作為主體材料，與bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium(III) (FIrpic)作為客體材料，進行藍色磷光有機發光二極體之研究，藉由調變元件結構，在A-o-CBZBIZ系統中得到57.45 cd/A 的最高電流效率、50.16 lm/W 的最高功率效率及27.87% 的最高外部量子效率。
而在第二部分，我們使用台大化學所梁文傑實驗室所提供的9,9''-(2-(1-phenyl-1H-benzo[d]imidazol-2-yl)-1,3-phenylene)bis(9H-carbazole) (o-DiCbzBz) 以及9,9'',9'',9''-(3-(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene- 1,2,4,5tetrayl)tetrakis(9H-carbazole) (o-4CzBz)作為主體材料，並分別搭配bis[4-(9,9-dimethyl-9,10-dihydroacridine) phenyl]sulfone (DMAC-DPS)和(4s,6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN)作為客體材料，來製作藍色和綠色熱活性型螢光有機發光二極體。藉由調變元件結構，在藍色熱活性型螢光有機發光二極體，我們得到32.37 cd/A 的最高電流效率、33.15 lm/W 的最高功率效率及18.46% 的最高外部量子效率，以及在綠色熱活性型螢光有機發光二極體，我們得到102.70 cd/A 的最高電流效率、103.60 lm/W 的最高功率效率及29.55% 的最高外部量子效率。

There are two topics in this thesis. In the first part, carbazole-N-benzimidazole bipolar materials 9-(2-(2-phenyl-1H-benzo[d]imidazol-1-yl)phenyl)-9H-carbazole (A-o-CBZBIZ) and 9-(3-(9H-carbazol-9-yl)-2-(2-phenyl-1H-benzo[d]imidazol-1-yl)phenyl)-9H-carbazole (A-dio-CBZBIZ) provided by Prof. Man-Kit Leung’s group, Department of Chemistry in National Taiwan University, were used as the host materials for blue phosphorescent organic light-emitting diodes (OLEDs), doped with bis[2-(4,6-difluorophenyl)pyridinato-C2,N](picolinato)iridium(III) (FIrpic). By tuning the device structure, maximum current efficiency of 57.45 cd/A, maximum power efficiency of 50.16 lm/W and maximum EQE of 27.87% were obtained in A-o-CBZBIZ system.
In the second part, (2-(1-phenyl-1H-benzo[d]imidazol-2-yl)-1,3-phenylene)bis(9H-carbazole) (o-DiCbzBz) and 9,9'',9'',9''-(3-(1-phenyl-1H-benzo[d]imidazol-2-yl)benzene- 1,2,4,5tetrayl)tetrakis(9H-carbazole) (o-4CzBz), provided by Prof. Man-Kit Leung’s group, Department of Chemistry in National Taiwan University, were utilized as host materials of the blue and green thermally activated delayed fluorescence (TADF) OLEDs. bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (DMAC-DPS) and (4s,6s)-2,4,5,6-tetra(9H-carbazol-9-yl)isophthalonitrile (4CzIPN) were used as blue and green TADF dopant materials, respectively. By tuning the device structure, in o-DiCbzBz-DMAC-DPS-based blue TADF OLEDs, maximum current efficiency of 32.37 cd/A, maximum power efficiency of 33.15 lm/W and maximum EQE of 18.46% were obtained. In o-4CzBz-4CzIPN-based green TADF OLEDs, we obtained a good performance with maximum current efficiency 102.7 cd/A, maximum power efficiency of 103.6 lm/W and maximum EQE of 29.55%.

摘要 I
Abstract III
Contents V
List of figures VI
List of tables VIII
Chapter 1 Introduction 1
1.1 Overview 1
1.2 Introduction of OLED 1
1.3 Review of blue phosphorescent host material 4
1.4 Review of blue and green TADF OLEDs 11
1.5 Motivation 20
Chapter 2 Experiments 21
2.1 Device Fabrication 21
2.2 Measurement systems of OLED 22
2.2.1 B-J-V characteristics, operation lifetime, and EQE measurements 22
2.2.2 Transient electroluminescence (TrEL) 23
Chapter 3 Carbazole-N-Benzimidazole bipolar materials as hosts of blue phosphorescent OLEDs 24
3.1 Photophysical characteristics of host materials 25
3.2 Device architecture of blue phosphorescent OLEDs 29
3.3 A-dio-CBZBIZ as blue OLED host material 31
3.4 A-o-CBZBIZ as blue OLED host material 35
Chapter 4 o-DiCbzBz and o-4CzBz as Host Materials for Blue and Green TADF OLEDs 39
4.1 Introduction 39
4.2 o-DiCbzBz: DMAC-DPS blue TADF OLED optimization 40
4.3 o-4CzBz:4CZIPN green TADF OLED optimization 46
Chapter 5 Summary 51
References 52

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