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

Abstract

The invention relates to iridium complexes having a novel main ligand and adopting 2-(5-phenyl-1,3,4-oxadiazole-2-)phenol as an auxiliary ligand. The main ligand of the series of iridium complex molecules is a chiral pinene group-containing (R-)4-pinene-2-phenylpyridine or (S-)4-pinene-phenylpyridine derivative. Compared with widely researched and reported iridium complexes, the novel iridium complexes have the advantages of high luminescence efficiency, small luminescence quenching effect caused by the concentration factor, high electron mobility, stable chemical properties, and easiness in sublimation and purification, and the devices have excellent performances. The molecular structure of the main ligand is modified, so the luminescence intensity and the efficiency of the complexes can be adjusted in a visible light wavelength range.

Description

【Technical field】 [0001] The invention relates to the technical field of organic electroluminescent devices, in particular to an iridium complex, a preparation method thereof, and a light-emitting device using the iridium complex. 【Background technique】 [0002] 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 for OLEDs. with 5d 7 6s ...

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

Images