Iridium complexes, preparation method thereof and electroluminescent device using iridium complexes

Abstract

The invention relates to three-element co-ligand iridium complexes with novel ligands. The ligands in molecules of the iridium complexes in the series are 2-(4,6-bis(trifluoromethyl)pyridine-3-)quinoline, 2-(4,6-bis(trifluoromethyl)pyridine-4-)quinoline, 2-(4,6-bis(trifluoromethyl)pyridine-3-)isoquinoline, 2-(4,6-bis(trifluoromethyl)pyridine-4-)isoquinoline, 2-(4,6-bis(trifluoromethyl)pyridine-3-)quinazoline, 2-(4,6-bis(trifluoromethyl)pyridine-4-)quinazoline, 2-(4,6-bis(trifluoromethyl)pyridine-3-)phthalazine and 2-(4,6-bis(trifluoromethyl)pyridine-4-)phthalazine derivatives. The novel iridium complexes have the advantages that the luminous efficiency is high, the chemical property is stable, sublimation purification is easy and the like, and besides, the performance of a device is good. The luminous intensity and efficiency of the ligands can be adjusted in the wavelength coverage of red light through a molecular structure modifying the ligands, which brings convenience to design and production of organic electroluminescent displays and lighting sources.

Description

[0001] 【Technical field】 [0002] The invention relates to the technical field of organic electroluminescent devices, in particular to a class of iridium complexes, a preparation method thereof and a light-emitting device using the iridium complexes. [0003] 【Background technique】 [0004] Against the background of increasing global energy demand and worrying ecological environment, governments of various countries have vigorously developed sustainable energy-saving technologies and industries based on high technology. Organic electroluminescent devices (OLEDs) have attracted much attention because of their advantages such as wide viewing angle, high brightness, low energy consumption and flexible devices, and are known as the key technology that will dominate the future display world. In recent years, a large number of studies have shown that among many complexes of heavy metal elements, iridium complexes are considered to be the most ideal choice of phosphorescent materials ...

AI Technical Summary

Problems solved by technology

In addition, in the current commonly used materials, the hole mobility of hole transport materials is much higher than that of electron transport materials, and the commonly used host materials are mainly hole transport, which will lead to a large number of redundant holes. Aggregation of holes at the interface between the light-emitting layer and the electron-transporting layer

These factors can lead to reduced efficiency and severe efficiency roll-off

Studies have shown that if the iridium complex has a high electron transport ability, it can effectively increase the transport and distribution of electrons in the light-emitting layer, broaden the electron-hole area, balance the number of electron-hole pairs, and greatly improve the device. efficiency, the reduced efficiency of the roll-off

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