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For OLED (Organic Light Emitting Diodes) phosphorescent materials include some heavy metals such as iridium, platinum complexes, these complexes central ion d orbitals on the strong spin-orbit coupling lead to singlet and triplet energy level mixing The triplet light appears, so that the internal quantum efficiency of material from 25% to nearly 100%. Wherein the metal iridium complex phosphorescent due to having a short life and high luminous efficiency and become a research hotspot. By ligand design and transformation properties of the luminescent material can be changed to improve the compatibility of the main guest material, thereby improving the luminous efficiency of the device, brightness, prolong the service life of the device. In this thesis, phosphorescent materials and devices for the current problems, such as: triplet exciton lifetime is too long, luminous efficiency, quality is not high, etc., for a new Iridium Complexes Molecular Design, Synthesis and Electroluminescent Properties research. In this dissertation, the main design process includes two aspects, one series of new synthetic ligands, these ligands with iridium trichloride, to give a new Iridium complexes of these complexes with fluorescence spectroscopy NMR and UV spectroscopy for structural characterization; second is to use synthetic complexes as luminescent object, the light emitting body doped 4,4 '-N, N'-dicarbazole-biphenyl (CBP) to prepare a multilayer structure electroluminescent devices to study their electroluminescent properties. Specific work include: 1, 2 traditional - aryl pyridine ligand structural modification synthesized four different conjugated ligand of the metal, it is desirable in the pyridine ring 4 - position to access different substituents such as phenyl, methyl, t-butyl and the like, thereby regulating the ligand conjugated system, to obtain a satisfactory efficiency of energy transfer, emission wavelength, and can produce a spatial effect, reducing the triplet exciton quenching from off phenomenon; fluorinated on the phenyl ring, to improve luminescent properties, favor deposition, increasing film formation and improve the stability of the device, by means of these ligands and iridium trichloride Synthesis twelve new complexes, the use of 1HNMR, 13CNMR, PL, and UV, etc. The complexes were characterized. In complexes Ir (DFPP) 2 (pic) as a light emitting dopant in the host material CBP guest, to prepare a multilayer structure work device, of about 6 volts at a low driving voltage, the device can emit relatively strong blue-green phosphor, wavelength of 498nm, maximum brightness of 24220 cd/m2, the maximum efficiency of 5.47 cd / A, the quantum efficiency of 3.05%. The results show that the device exhibits a phosphorescent electroluminescent properties, the emission wavelength of the device structure between the ligand, the C ^ N ligands access fluoro substituents, the emission wavelength is shifted to blue; increased ligand conjugated system, emission wavelength red shift. 2, were designed and synthesized a new structure with two rigid or lesser degree can be reversed, the type of conjugation with the ring of the metal body, and thus prepare the four corresponding iridium complexes, using 1HNMR, 13CNMR, PL, as well as UV, etc. The complexes were characterized. In complexes (BIIO) 2Ir (acac) as a light guest host material doped in CBP, study their electroluminescent properties. 6 coat the low voltage drive, the device emission wavelength of 498 nm, the maximum external quantum efficiency and maximum brightness, respectively, and 11.2% 79640 cd/m2. The results showed that the ligand can increase the rigidity of such complexes the external quantum efficiency, brightness and color with a good light changes.
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