Nitrogen-containing heterocyclic compound, application thereof and organic light-emitting device

Abstract

The invention relates to a nitrogen-containing heterocyclic compound. The heterocyclic compound has a structure shown in the following formula (1). The nitrogen-containing heterocyclic compound comprises asymmetric carboline groups and carbazole groups, so that molecules have excellent hole and electron transmission performance at the same time; meanwhile, bridged N heterocyclic rings and electron-withdrawing groups such as triazine, phenylcyano, pyrazine, pyridylcyano and the like are introduced into the molecular structure, so that improvement of the molecular electron transmission capability is facilitated. The nitrogen-containing heterocyclic compound has excellent bipolar transmission capacity, and can widen a charge composite area and reduce efficiency roll-off. Through introductionof different carboline groups and through change of relative substitution positions of carbazole groups and / or carboline groups, the energy level of the compound can be regulated and controlled, so that materials with different energy levels are screened, and selection and collocation of device materials are facilitated.

Description

technical field [0001] The present disclosure relates to the field of organic electroluminescent materials, in particular, to a nitrogen-containing heterocyclic compound, its application and an organic electroluminescent device. Background technique [0002] The research on organic electroluminescent materials and devices began in the 1960s. According to different luminescent principles, organic electroluminescence can be divided into two categories: electroluminescence and electrophosphorescence. The triplet excitons of fluorescent materials are subject to spin prohibition, and can only return to the ground state in a non-radiative form to generate photons, resulting in the internal quantum efficiency of electroluminescence being limited to within 25%. Electrophosphorescence can make full use of the energy of singlet excitons and triplet excitons, so theoretically the internal quantum efficiency of phosphorescent devices can reach 100%. In 1998, Ma et al. of Hong Kong Uni...

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Problems solved by technology

[0004] However, the current thermally activated delayed fluorescence (TADF) materials have a mismatch between the hole transport ability and the electron transport ability, and the reverse intersystem crossing rate (k RISC ) is low, triplet-polaron annihilation (TPA) is more serious, etc.

[0005] In addition, in organic electroluminescent materials, its hole transport ability is often better than electron transport ability, which leads to unbalanced electron and hole transport and affects the luminous efficiency of electroluminescent devices.

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