國 立 交 通 大 學
應用化學研究所
博 士 論 文
新穎銥磷光體之金屬化合物的合成、
特性鑑定與應用
Synthesis, Characterization and Applications of
Novel Phosphorescent Iridium Metal Complexes
研 究 生：洪曉雯 (Hsiao-Wen Hung)
指導教授：陳登銘 博士 (Dr. Teng-Ming Chen)
Synthesis, Characterization and Applications of Novel Phosphorescent Iridium Metal Complexes
Student：Hsiao Wen Hong Advisors：Dr. Teng-Ming Chen
Department of Applied Chemistry National Chiao Tung University
ABSTRACT
This thesis is divided into eight chapters. The work presented here describes the development of novel phosphors, charge-carriers and charge-blockers for Organic light emitting device (OLED). The first chapter describes history of the choice of organic technology and the Early Years of Development. Chapter 2 how these devices work, how the materials affect device properties and energy transfer principles. Chapter 3 introduces the development of a series of 2-phenylbenzoxazole (bo) as the cyclometalated ligand with substituents (i.e., -CF3, -F, -Me, -OMe) showing
different electronic properties to synthesize mononuclear emissive complex with iridium(III) are reported in this chapter. Chapter 4 describes the research works of synthesis and Electroluminescence studies of the New Iridium(III) Complexes Posseessing the 2-Phenyl-1-pyrroline Ligands. Chapter 5 discusses the quantum efficiency properties of Ir complexes with red-orange emitting Ir(III) complexes. We demonstrate that the Ir complexes used as dopants in organic electrophosphorescent diodes exhibit very high PL quantum efficiency ( ηPL ) in the solid-state. We have also reported and
device. Chapter 6 presents the study of white-Emitting Electrophosphorescent OLEDs. We have developed and fabricated highly efficient white organic light-emitting devices (WOLEDs) with very broad emission based on an orange emitter, bis- (4-triflurophenyl)benzothiozolato-N,C2’) iridium (acetylacetonate) [Ir(4-CF3bt)2acac] and tri(2-phenylquinoline) iridium complexes. A
white-light device with one of the highest EL efficiencies of 8.6 % with Commission Internationale d’Eclairage (CIE) coordinates of (x＝0.350, y＝ 0.396) has been demonstrated. Chapter 7 describes the investigation of the synthesis new dendrimer and properties of solution processable phosphorescent. We have pursued the development of highly luminescent solution-processible electrophosphorescent dendrimers. These dendrimers are characterized by high PL quantum yield (QY) vales than small molecules in the film. We also report the electrochemical, photophysical, and device properties of the dendrimer. The last Chapter 8 summarized all experimental results and future works in the dissertation.
Contents
Chapter 1 : Introduction 1
1.1 History of the choice of organic technology……….1
1.2 The work of Tang and Vanslyke………...6
1.3 Full color active matrix displays……….11
1.4 The Early Years of Development………12
1.5 Summary……….21
1.6 References………...21
Chapter 2 : Principles 23
2.1 How does it work………..23
2.2 The Born-Oppenheimer approximation………...24
2.3 Basic model of exciton formation……….25
2.4 Charge transfer states and relaxation paths………...……29
2.5 Triplet harvesting………..31
2.6 Exciton formation at matrix molecules versus charge carrier trapping at emitter compounds………..33
2.7 Fluorescence and Phosphorescence………..34
2.8 Förster energy transfer………..37
2.9 Dexter energy transfer………...40
2.10 Summary……….42
Chapter 3 : Effect of Substituents in the photoluminescent and
electroluminescent properties of substituted cyclometalated
iridim(III) complexes 46 Abstract………...……46 3.1 Introduction………...46 3.2 Experimental Section………....48 3.2.1 Materials……….……48
3.2.2 Optical Measurements and Compositions Analysis….…..48
3.2.3 Crystallography……….……….55
3.2.4 OLED Fabrication and Testing………….……….56
3.3 Results and discussions………56
3.3.1 Synthesis and Characterization of (x/ybo)2Ir(acac) complexes………56
3.3.2 UV-Vis Absorption spectra……….58
3.3.3 Photoluminescence (PL) spectra…………...……….59
3.3.4 Redox Chemistry………62
3.3.5 Structure of (CF3bo)2Ir(acac) Complex………..62
3.3.6 Description of OLED devices fabricated with (CF3bo)2 Ir (acac), (CH3bo)2Ir(acac) and (bo)2Ir(acac) dopants in the emissive layer………..65
3.4 Conclusions………...69
3.5 References……….69
Chapter 4 : Synthesis and Electroluminescence studies of the New Iridium(III) Complexes Posseessing the 2-Phenyl-1-pyrroline
Ligands 72
Abstract………...72
4.1 Introduction………...73
4.2 Experimental Section………73
4.2.1 Materials……….73
4.2.2 Optical Measurements and Compositions Analysis……...73
4.2.3 Syntheses of mononuclear iridium(III) complex dopants..73
4.2.4 Crystallography………..76
4.2.5 OLED Fabrication and Testing………...76
4.3 Results and discussions……….77
4.3.1 Synthesis and Characterization of iridium(III) complexes.77 4.3.2 Photoluminescence (PL) spectra………....79
4.3.3 Structure of (2-4-fluorophenyl-1-pyrroline)3Ir Complex...80
4.3.4 Cyclicvoltametric study………..83
4.3.5 Decay lifetime………83
4.3.6 Electroluminescence………...84
4.4 Conclusions...87
4.5 References……….87
Chapter 5 : High phosphorescence quantum efficiency of red-orange emitting Ir(III) complexes 90
Abstract………...90
5.1 Introduction………...…91
5.2 Experimental Section………92
5.2.2 Instruments……….92
5.2.3 Crystallography………..92
5.2.4 Film for measurement of absolute PL quantum efficiency.93 5.2.5 OLED Fabrication………..94
5.2.6 Syntheses………95
5.3 Results and discussions……….97
5.3.1 Absorption spectra………..97
5.3.2 Description of the structure of (CF3bt)2Ir(acac)………….98
5.3.3 Property of Solid-state………..101
5.3.4 Description of OLEDs prepared with (CF3bt)2Ir(acac) dopants in emissive layer with varying concentration…..104
5.4Conclusions………..106
5.5 References………...106
Chapter 6 : White Phosphorescent Organic Light-emitting Devices 109 Abstract……….109
6.1 Introduction……….110
6.2 Experimental Section……….……..112
6.2.1 Materials Synthesis………...112
6.2.2 OLED Device Fabrication………114
6.3 Results and discussions………...115
6.4 Conclusions……….124
6.5 References………...125
phosphorescent 128
Abstract……….128
7.1 Introduction……….129
7.2 Experimental Section………..130
7.2.1 Materials Synthesis………..130
7.2.2 Fabrications and Characterizations of OLEDs based on Ir complex……….141
7.2.3 Solution quantum yield Measurement……….…….142
7.3 Results and Discussions…..………143
7.3.1 Photophysical Properties………..143
7.3.2 Electrochemical Properties………..147
7.4 Conclusions……….158
7.5 References………...159
Chapter 8 : Conclusion and Future Work 161
List of Publication and Presentations 163
Awards 166
