Phosphorescent iridium complex as OLED doping material and application of phosphorescent iridium complex

Abstract

The invention discloses a phosphorescent iridium complex as an OLED doping material, the iridium complex uses metal iridium as a structure core, has high glass transition temperature and decomposition temperature, is applied to OLED devices, is used as a doping material of a luminescent layer material, and can emit phosphorescence under the action of an electric field, the current efficiency and the external quantum efficiency of a device are remarkably improved when the phosphorescent iridium complex is used as a light-emitting layer doping material, meanwhile, the service life of the device is greatly prolonged, and the phosphorescent iridium complex has good photoelectric performance when the phosphorescent iridium complex is used as the light-emitting layer doping material.

Description

technical field [0001] The invention relates to the field of optoelectronic technology, in particular to a phosphorescent iridium complex as an OLED doping material and its application on an OLED device. Background technique [0002] Compared with liquid crystal display (LCD), organic electroluminescent device (OLED) has low driving voltage; high luminous brightness and luminous efficiency; wide luminous viewing angle and fast response speed; in addition, it is ultra-thin and can be fabricated on flexible panels, etc. advantage. Known as the '21st century flat panel display technology', organic electroluminescent materials are divided into two categories: organic electroluminescent materials and organic electrophosphorescent materials. Among them, organic electroluminescence is the result of radiation inactivation of singlet excitons. In the process of organic electroluminescence, triplet excitons and singlet excitons are generated at the same time, usually the ratio of si...

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Problems solved by technology

[0004]However, the current phosphorescent materials still have the following disadvantages: 1. Due to the existence of coordination bonds, the thermal stability of the material is poor, especially when the device works for a long time, Material prone to decomposition

2. The lifetime of the triplet state of the phosphorescent material is long, which leads to a serious impact on the triplet-triplet quenching of the material, resulting in a decrease in the efficiency and life of the device

3. The radiation rate of the material is low and the non-radiation rate is high, which causes the material to dissipate energy in the form of thermal energy in the excited state, resulting in a decrease in the fluorescence quantum efficiency of the material and a significant decrease in the efficiency of the device

However, it did not elaborate and explain the mechanism and reasons for the improvement of efficiency and life, and did not mention spectral FWHM and spectral chromaticity coordinates;

[0006] Furthermore, in Chinese patent CN103804426A, phenylpyridine derivatives are used as main ligands, and pyridyl azadibenzofuran derivatives are used as auxiliary ligands. Compared with the iridium complex of the auxiliary ligand of non-azadibenzofuran derivatives, the lifetime is improved, and the spectral FWHM is narrowed, but its efficiency is reduced; although the compound has been further modified to improve the efficiency, but Its luminous color is yellow-green, or even turns yellow, resulting in a serious green color cast; and the FWHM of the compound is still relatively large (≥60nm), and it is impossible to obtain a spectrum with high saturation color purity and narrow FWHM, which is not conducive to improving the efficiency and efficiency of the device. Declination

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