Organic electroluminescent material and device

Abstract

The invention provides an organic electroluminescent material and an application thereof in a device. An organic compound is represented by a general formula (1) shown in the description as follows, wherein Ar1 is a group, obtained through removing n+1 H from a C6-C30 aromatic ring or C3-C30 hetero aromatic ring; Ar2 represents one or two substituents represented by a formula (2) shown in the description, wherein X is selected from a single bond, O, S, NR9 and CR10R11; R1 represents n substituents of Ar1, separately independently selected from cyano, nitro, alpha-bit-fluoro-substituted C1-C10alkyl, -C(O)R12 and -C(O)NR13, and n is an integer not smaller than 1; R2 is selected from H, C1-C10 alkyl, C3-C10 cycloalkyl, C1-C10alkoxy and cyano; R3 to R8 each independently represents one or anymultiple substituents and is independently selected from H, halogen, -C(O)R12, C1-C10 alkyl, C3-C10 cycloalkyl, C1-C10 alkoxy, C6-C30 aryl, C3-C30 heteroaryl or combinations thereof; random adjacenttwo substituents can form a ring; R9 to R13 each is independently selected from C1-C10 alkyl, C6-C30 aryl and C3-C30 heteroaryl; and a molecule only has one C-N dicarbazyl.

Description

technical field [0001] The invention relates to a novel organic electroluminescent material and its application in organic electroluminescent devices, belonging to the technical field of organic electroluminescent display. Background technique [0002] Under the condition of electro-excitation, organic electroluminescent materials will produce 25% singlet state and 75% triplet state, and traditional fluorescent materials can only use singlet state excitons due to spin prohibition. In order to utilize triplet excitons, researchers have proposed many methods, the most notable of which is the utilization of phosphorescent materials. However, the T1 lifetime of phosphorescent materials is generally above 1 μs, which is much higher than the lifetime of fluorescent materials of tens of nanoseconds, so the efficiency rolls off seriously at high current densities, and due to the use of rare heavy metals, the materials are relatively expensive, which is not conducive to Product cost...

AI Technical Summary

Problems solved by technology

[0015] However, the above two types of hosts have the following defects in application: the hole-type carbazole-based host material has an uneven distribution of excitons due to its weak electron transport ability, and the device efficiency rolls off seriously; the phosphorus-oxygen compound host material although High efficiency, but unsatisfactory device lifetime due to instability of phosphine groups

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