Light-emitting material, display panel, and display apparatus

Abstract

The present disclosure relates to the field of organic electroluminescent materials, and relates to a compound and a use thereof as a light-emitting material, an organic electroluminescent device, a display panel, and a display apparatus. The compound provided by the present disclosure is a compound having a structural formula of formula (I), wherein the meaning of each group is the same as that defined in the description.

Description

Light-emitting material, display panel and display device

[0001] The present disclosure claims priority to the Chinese patent application No. 202410683541.2, filed on May 29, 2024, and entitled "A light-emitting material, display panel and display device", the content of which is incorporated herein by reference. TECHNICAL FIELD

[0002] The present disclosure belongs to the field of organic electroluminescent materials, and relates to a light-emitting material, display panel and display device, more particularly, to a rigid organic small molecule light-emitting material constructed to realize the property of Thermally-activated Delayed Fluorescence (TADF) through space charge transfer, and to develop an electroluminescent device with high efficiency. BACKGROUND

[0003] As a new type of display technology, organic electroluminescent technology has the unique advantages of self-luminescence, wide viewing angle, low energy consumption, high efficiency, rich color, fast response speed, wide temperature range, low driving voltage, flexible and transparent display panel, and environmental friendliness, and is considered as one of the most competitive flat panel display technologies.

[0004] An organic electroluminescent device is an electroluminescent device with organic materials as functional materials and driven by an electric field. Its light-emitting principle is to realize light-emitting through carrier injection and recombination under the drive of an electric field. Compared with traditional inorganic functional materials, organic functional materials have the characteristics of easy preparation, easy property control, flexibility, and good film-forming property. At the same time, the electroluminescent device based on organic functional materials has the advantages of simple preparation process, easy realization of large-area display, and low manufacturing cost, showing a broad application prospect.

[0005] However, the luminescent efficiency of the organic luminescent material needs to be further improved. SUMMARY

[0006] The following is a summary of the subject matter detailed in the description. This summary is not intended to limit the scope of protection of the present disclosure.

[0007] One purpose of the embodiments of the present disclosure is to provide a compound, a display panel and a display device comprising the compound which can be used as a light-emitting material.

[0008] The inventors of the present disclosure find that the compound provided by the present disclosure as the light-emitting material fixes the donor unit on the spiro-heterocyclic structure, so that it has a rigid structure, and fixes the acceptor unit on the connecting group, and performs coplanar stacking with the donor unit, and arranges into various rigid coplanar conformations; at the same time, due to the presence of heteroatoms on the spiro-heterocyclic ring, the donor unit tilts to the acceptor unit side, so that the spatial distance between the donor and the acceptor is smaller, and the spatial interaction is stronger, thus having a space charge transfer property, so as to realize TADF, and taking it as a guest light-emitting material or a sensitizer, a series of electroluminescent devices with high light-emitting performance are developed.

[0009] To this end, the first aspect of the present disclosure provides a compound. According to an embodiment of the present disclosure, the compound has a structural formula of formula (I):

[0010] X1and X2are each independently selected from one of O, S, Se, C=O, S(=O)2, CR6R7, SiR6R7, NR6, PR6, P(=O)R6, BR6; or X1and X2are absent or a direct connection bond, and at most one of X1, X2is a direct connection bond;

[0011] X3is selected from S, O or CR8R9;

[0012] A1, A2, A3, A4, A5are each independently selected from C6-C18 aryl unsubstituted or substituted with at least one substituent, 5-18 membered heteroaryl unsubstituted or substituted with at least one substituent;

[0013] R1, R2, R3, R4, R5each independently represent 1 to 3 substituents each independently selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, unsubstituted or substituted with at least one substituent C1-C18alkyl, unsubstituted or substituted with at least one substituent C2-C18alkenyl, unsubstituted or substituted with at least one substituent C2-C18alkynyl, unsubstituted or substituted with at least one substituent C3-C18cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18alkoxy, unsubstituted or substituted with at least one substituent C6-C18aryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heteroaryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heterocyclyl; or the 1 to 3 substituents are arranged in such a way that they can bond with adjacent groups to form a 5- to 18-membered ring; R6, R7each independently are selected from the group consisting of unsubstituted or substituted with at least one substituent C1-C18alkyl, unsubstituted or substituted with at least one substituent C2-C18alkenyl, unsubstituted or substituted with at least one substituent C2-C18alkynyl, unsubstituted or substituted with at least one substituent C3-C18cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18alkoxy, unsubstituted or substituted with at least one substituent C6-C18aryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heteroaryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heterocyclyl; or R6, R7are arranged in such a way that they can bond with adjacent groups to form a 5- to 18-membered ring;

[0014] the substituents of the C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl;

[0015] R8and R9each independently are selected from the group consisting of unsubstituted or substituted with at least one substituent C1-C6alkyl, unsubstituted or substituted with at least one substituent C1-C6alkoxy;

[0016] or the substituents of the C1-C6alkyl, C1-C6alkoxy are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl;

[0017] L is a direct bond or a linking group selected from an oxygen atom, C1-C6 alkylene, C1-C6 alkylenoxy, C6-C18 arylene, C6-C18 arylenoxy, 5-18 membered heteroarylene, 5-18 membered heteroarylenoxy, which are unsubstituted or substituted by at least one substituent;

[0018] the substituents of the C1-C6 alkylene, C1-C6 alkylenoxy, C6-C18 arylene, C6-C18 arylenoxy, 5-18 membered heteroarylene, 5-18 membered heteroarylenoxy are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl;

[0019] A is an electron-withdrawing heterocyclic group having electron-transporting ability.

[0020] In order to further study the light-emitting properties of TADF materials and realize high-efficiency light-emitting in electroluminescent devices, the present disclosure designs a light-emitting material including a compound with a structural formula of formula (I), which fixes the donor unit on the spiro heterocyclic structure, so that it has a rigid structure, which can reduce the vibration relaxation phenomenon caused by the change of the molecular configuration of the material molecules under the condition of electric field excitation, and improve the color purity of light-emitting; at the same time, the acceptor unit is fixed on the linking group and stacked with the donor unit in a coplanar manner, and arranged into various rigid coplanar conformations, which can realize the overlap of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) in space and realize the spatial charge transfer; due to the presence of heteroatoms on the spiro heterocyclic ring, the donor unit tilts towards the acceptor unit, so that the spatial distance between the donor and the acceptor is smaller, and the spatial interaction is stronger, so as to realize more efficient spatial charge transfer light-emitting properties. A TADF organic light-emitting small molecule is constructed therefrom, and the TADF organic light-emitting small molecule is used as a guest light-emitting material or a fluorescent light-emitting layer sensitizer or a phosphorescent light-emitting layer sensitizer, and a series of electroluminescent devices with high efficiency are developed.

[0021] According to an embodiment of the present disclosure, in the compound represented by formula (I):

[0022] X1and X2are each independently selected from one of O, S, Se, C=0, S(=0)2, CR6R7, SiR6R7, NR6, PR6, P(=0)R6, BR6; or X1and X2are absent or a direct bond, and at most one of X1, X2is a direct bond;

[0023] X3is selected from S, O or CR8R9;

[0024] A1, A2, A3, A4, A5are each independently selected from C6-C18 aryl unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl unsubstituted or substituted by at least one substituent;

[0025] R1, R2, R3, R4, R5each independently represent one to three substituents each independently selected from hydrogen, halogen, C1-C18 alkyl unsubstituted or substituted by at least one substituent, C6-C18 aryl unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl unsubstituted or substituted by at least one substituent, 5-18 membered heterocyclyl unsubstituted or substituted by at least one substituent;

[0026] R6, R7are each independently selected from C1-C18 alkyl unsubstituted or substituted by at least one substituent, C6-C18 aryl unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl unsubstituted or substituted by at least one substituent, 5-18 membered heterocyclyl unsubstituted or substituted by at least one substituent;

[0027] the substituents of said C1-C18 alkyl, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl;

[0028] R8and R9are each independently selected from C1-C6 alkyl unsubstituted or substituted by at least one substituent, C1-C6 alkoxy unsubstituted or substituted by at least one substituent;

[0029] or, the substituents of said C1-C6 alkyl, C1-C6 alkoxy are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl;

[0030] L is a direct bond or a linking group selected from an oxygen atom, C1-C6 alkylene, which is unsubstituted or substituted by at least one substituent, C6-C18 arylene, which is unsubstituted or substituted by at least one substituent, C6-C18 aryloxy, which is unsubstituted or substituted by at least one substituent, 5-18 membered heteroarylene, which is unsubstituted or substituted by at least one substituent;

[0031] the substituents of the C1-C6 alkylene, C6-C18 arylene, C6-C18 aryloxy, 5-18 membered heteroarylene are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl.

[0032] According to embodiments of the present disclosure, in the compound of formula (I):

[0033] X1and X2are each independently selected from one of O, S, C=O, CR6R7, NR6, BR6; or X1and X2are absent or a direct bond, and at most one of X1, X2is a direct bond;

[0034] X3is selected from S, O or CR8R9;

[0035] A1, A2, A3, A4, A5are each independently selected from C6-C18 aryl, which is unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl, which is unsubstituted or substituted by at least one substituent;

[0036] R1, R2, R3, R4, R5each independently represent one to three substituents, each independently selected from the group consisting of hydrogen, halogen, C1-C18 alkyl, which is unsubstituted or substituted by at least one substituent, C6-C18 aryl, which is unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl, which is unsubstituted or substituted by at least one substituent, 5-18 membered heterocyclyl, which is unsubstituted or substituted by at least one substituent;

[0037] R6, R7are each independently selected from the group consisting of C1-C18 alkyl, which is unsubstituted or substituted by at least one substituent, C6-C18 aryl, which is unsubstituted or substituted by at least one substituent, 5-18 membered heteroaryl, which is unsubstituted or substituted by at least one substituent, 5-18 membered heterocyclyl, which is unsubstituted or substituted by at least one substituent;

[0038] R8and R9are each independently selected from the group consisting of C1-C6 alkyl, which is unsubstituted or substituted by at least one substituent, C1-C6 alkoxy, which is unsubstituted or substituted by at least one substituent;

[0039] L is a direct bond or a linking group selected from C1-C6 alkylene, which is unsubstituted or substituted by at least one substituent, C6-C18 arylene, which is unsubstituted or substituted by at least one substituent, C6-C18 aryloxy, which is unsubstituted or substituted by at least one substituent, 5-18 membered heteroarylene, which is unsubstituted or substituted by at least one substituent.

[0040] According to embodiments of the present disclosure, in the compound represented by formula (I):

[0041] R1, R2, R3, R4, R5 each independently represents 1 to 3 substituents each independently selected from hydrogen, unsubstituted C6-C18 aryl;

[0042] R6, R7 each independently selected from unsubstituted C1-C6 alkyl, unsubstituted C6-C12 aryl, unsubstituted 5-14 membered heteroaryl;

[0043] R8 and R9 each independently selected from unsubstituted C1-C6 alkyl;

[0044] L is a direct bond or a linking group selected from unsubstituted C1-C6 alkylene, unsubstituted C6-C18 arylene, unsubstituted C6-C18 aryloxyylene, unsubstituted 5-18 membered heteroarylene, wherein the heteroatom in the unsubstituted 5-18 membered heteroarylene is N.

[0045] According to embodiments of the present disclosure, in the compound represented by formula (I), A is selected from triazine and derivatives thereof, benzophenone and derivatives thereof, diphenyl sulfone and derivatives thereof, oxadiazole and derivatives thereof, bipyridine and derivatives thereof, phenyl nitrile and derivatives thereof, or boron heterocyclic acceptor and derivatives thereof.

[0046] According to embodiments of the present disclosure, in the compound represented by formula (I), A is selected from one of the following:

[0047] wherein, in , Y1, Y2, Y3 each independently selected from N, CH, and at least one is N; in , Y1, Y2 each independently selected from N, CH, Y3 is selected from NH, O, CH2, and at least one of Y1, Y2, Y3 contains N atom;

[0048] n is any integer from 0 to 5;

[0049] R 10 , R 11each independently represents 1 to 5 substituents each independently selected from the group consisting of hydrogen, a substituted or unsubstituted C1-C18 alkyl group, a C2-C18 alkenyl group which is unsubstituted or substituted with at least one substituent, a C2-C18 alkynyl group which is unsubstituted or substituted with at least one substituent, a C3-C18 cycloalkyl group which is unsubstituted or substituted with at least one substituent, a C1-C18 alkoxy group which is unsubstituted or substituted with at least one substituent, a C1-C18 alkylthio group which is unsubstituted or substituted with at least one substituent, an amine group which is unsubstituted or substituted with at least one substituent, a C6-C30 arylthio group which is unsubstituted or substituted with at least one substituent, a C6-C30 aryloxy group which is unsubstituted or substituted with at least one substituent, a C6-C30 aryl group which is unsubstituted or substituted with at least one substituent, a 5-30 membered heteroaryl group which is unsubstituted or substituted with at least one substituent;

[0050] The substituents of the C1-C18 alkyl group, C2-C18 alkenyl group, C2-C18 alkynyl group, C3-C18 cycloalkyl group, C1-C18 alkoxy group, C1-C18 alkylthio group, amine group, C6-C30 arylthio group, C6-C30 aryloxy group, C6-C30 aryl group, 5-30 membered heteroaryl group are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl group, C2-C18 alkenyl group, C2-C18 alkynyl group, C3-C18 cycloalkyl group, C1-C18 alkoxy group, C6-C18 aryl group, 5-18 membered heteroaryl group, 5-18 membered heterocyclyl group.

[0051] According to an embodiment of the present disclosure, R 10 , R 11 each independently represents 1 to 5 substituents each independently selected from the group consisting of hydrogen, a C1-C18 alkyl group which is unsubstituted, a C6-C30 aryl group which is unsubstituted, a 5-30 membered heteroaryl group which is unsubstituted.

[0052] According to an embodiment of the present disclosure, n is 1 or 2;

[0053] R 10 , R 11 each independently represents 1 to 5 substituents each independently selected from the group consisting of hydrogen, a C1-C10 alkyl group which is unsubstituted, a C6-C18 aryl group which is unsubstituted, a 5-18 membered heteroaryl group which is unsubstituted, the 5-18 membered heteroaryl group having N as a heteroatom,

[0054] and when R 10 or R 11 is a substituent of a benzene ring, R 10 , R 11 each independently forms a fused ring with the benzene ring to which it is attached.

[0055] According to an embodiment of the present disclosure, the compound shown in formula (I) is any one of the following compounds:

[0056] According to an embodiment of the present disclosure, the compound includes a donor group and an acceptor group, the acceptor group is A in the compound shown in formula (I), and the donor group is the rest of the compound shown in formula (I) except -L-A;

[0057] The spatial distance between the center of the plane where the donor group is located and the center of the plane where the acceptor group is located is D, wherein D is not greater than 3.5 angstroms.

[0058] According to an embodiment of the present disclosure, the center of the plane where the donor group is located refers to the center of the plane where at least 5 atoms in the conjugated plane are selected as the center of the plane of the donor group;

[0059] The center of the plane where the acceptor group is located refers to the center of the plane where the conjugated ring structure is located, and the distance d1 from any conjugated atom in the conjugated ring structure to the center of the plane where the donor group is located is not greater than 3.8 angstroms.

[0060] The second aspect of the present disclosure provides the use of the compound of the first aspect as described above as a light-emitting material.

[0061] The third aspect of the present disclosure provides an organic electroluminescent device. According to an embodiment of the present disclosure, the organic electroluminescent device includes a light-emitting layer, and the material of the light-emitting layer includes the compound of the first aspect.

[0062] The organic electroluminescent device prepared by using the compound of the first aspect of the present disclosure can achieve the device performance of high efficiency, low operating voltage and long service life.

[0063] The scheme of the embodiment of the present disclosure uses a rigid spiro ring structure to fix a nitrogen-containing electron-rich fused heterocyclic ring to construct a donor unit, and limits the donor unit and the acceptor unit on the connecting group to achieve a close-packed coplanar conformation. The connecting group breaks the conjugation between the donor and the acceptor, and at the same time, the presence of heteroatoms on the spiro ring structure makes the donor unit tilt towards the acceptor unit, so that the spatial distance between the donor and the acceptor is smaller. In this way, a TADF type organic light-emitting material with space charge transfer property is developed.

[0064] By controlling the type of heteroatom on the connected spirocyclic moiety (mainly regulated by X3), the steric hindrance effect is regulated, so that the donor unit on the spirocyclic structure is tilted to the connecting side of the acceptor unit (—L—A), and is close to the acceptor unit structure (A) in spatial distance, so that the HOMO and LUMO orbitals exist in the spatial overlap of the electron cloud, and compared with the electron cloud overlap of the TADF material molecule on the chemical bond, a smaller singlet-triplet energy difference (ΔE ST ) value can be achieved to promote the fast reverse intersystem crossing (RISC) process and realize high-efficiency TADF light-emitting process. Based on this, the light-emitting material can be used to prepare an organic electroluminescent device to realize high-efficiency light-emitting performance.

[0065] The fourth aspect of the present disclosure provides a display panel. According to an embodiment of the present disclosure, the display panel comprises a light-emitting unit, and the light-emitting unit comprises a light-emitting layer, and a material of the light-emitting layer comprises the compound of the first aspect.

[0066] Therefore, the display panel has all the characteristics and advantages of the compound described above, which will not be repeated here. In general, the display panel has good light-emitting performance and display effect.

[0067] The fifth aspect of the present disclosure provides a display device. According to an embodiment of the present disclosure, the display device comprises the display panel of the fourth aspect. The display device has all the characteristics and advantages of the display panel described above, which will not be repeated here. In general, the display device has good display effect.

[0068] The scheme of the embodiment of the present disclosure constructs a donor unit with a rigid structure by using a spiro-heterocyclic structure, and limits different donor units on the connecting group to realize a close-packed coplanar conformation, so that a close-packed structure is formed between the donor and the acceptor of the light-emitting material molecule. Such a light-emitting material has a smaller ΔE ST value to facilitate the occurrence of the RISC process; in addition, the HOMO and LUMO overlap in space at the excited state, realizing a spatial charge transfer process, so that a fast S1 state radiation transition exists to realize high-efficiency light-emitting, exhibiting excellent TADF properties. As a guest light-emitting material, a doped organic electroluminescent device can be prepared by a vacuum evaporation method to realize the device performance of high efficiency, low operating voltage and long service life.

[0069] Additional aspects and advantages of the present disclosure will be in part apparent and in part pointed out hereinafter in the description.

[0070] Other aspects can become apparent after reading and understanding the accompanying drawings and detailed description. Other aspects can become apparent after reading and understanding the accompanying drawings and detailed description. BRIEF DESCRIPTION OF DRAWINGS

[0071] The accompanying drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and serve to explain the principles of the present disclosure, but are not intended to limit the present disclosure.

[0072] FIG. 1 is a structural schematic diagram of a space-charge transfer type TADF material molecule according to an embodiment of the present disclosure;

[0073] FIG. 2 is a structural schematic diagram of an organic electroluminescent device according to an embodiment of the present disclosure;

[0074] FIG. 3 is a diagram of HOMO electron cloud distribution and LUMO electron cloud distribution of compounds 43, 2, 4, 44, 13, 62, 63, 75, 29, and 97.

[0075] Legend of reference signs: 1: substrate; 2: first electrode; 3: hole injection layer; 4: hole transport layer; 5: electron blocking layer; 6: light-emitting layer; 7: hole blocking layer; 8: electron transport layer; 9: electron injection layer; 10: second electrode; 11: donor group; 12: acceptor group; 13: linking group. DETAILED DESCRIPTION

[0076] In order to make the objectives, technical solutions, and advantages of the present disclosure clearer, the following will describe embodiments of the present disclosure in detail with reference to the accompanying drawings. It should be noted that the embodiments in the present disclosure and the features in the embodiments can be combined with each other as long as there is no conflict.

[0077] The embodiments of the present disclosure are not necessarily limited to the sizes shown in the drawings, and the shapes and sizes of the components in the drawings are preferred embodiments, and other shapes and sizes are also possible. In addition, the drawings schematically show ideal examples, and the embodiments of the present disclosure are not limited to the shapes or values shown in the drawings.

[0078] The endpoints of the ranges and any values in the ranges disclosed herein are not limited to the precise values stated. The ranges or values should be construed to be roughly around the ranges or values. For numerical ranges, the endpoints of the various ranges, the endpoints of the various ranges and individual point values, and the individual point values can be combined to form one or more new numerical ranges, which should be considered as specifically disclosed herein.

[0079] The size and proportion relationship between each film layer or component in the drawings of the present disclosure can be used as a reference in the actual process, which is a preferred embodiment of the technical effect, but is not limited thereto. For example, the thickness and spacing of each film layer can be adjusted according to actual needs.

[0080] For the purposes of the present disclosure, certain terms are specifically defined below. Unless specifically defined elsewhere in this document, the terms used herein have the meanings that are commonly understood by one of ordinary skill in the art in the field of the present disclosure.

[0081] In this document, the terms "comprising" or "including" are to be construed as open-ended, that is, as including, but not limited to, whatever follows the term. Without further qualification, the term "comprising" means including, but not limited to, whatever follows the term.

[0082] It should be noted that numeric ranges recited within the specification and claims of this disclosure, when the range is of integers, are to be understood to include both the integers within the defined range and the integers within the range that are not recited. For example, the integers "0-5" are to be understood to include the integers 0, 1, 2, 3, 4, and 5.

[0083] The term "C1-C18alkyl" is to be understood as meaning a straight-chain or branched saturated monovalent hydrocarbon group having 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms. Said alkyl group is, for example, a methyl, ethyl, propyl, butyl, pentyl, hexyl, isopropyl, isobutyl, sec-butyl, tert-butyl, isopentyl, 2-methylbutyl, 1 -methylbutyl, 1 -ethylpropyl, 1,2-dimethylpropyl, neopentyl, 1,1 -dimethylpropyl, 4-methylpentyl, 3-methylpentyl, 2-methylpentyl, 1 -methylpentyl, 2-ethylbutyl, 1 -ethylbutyl, 3,3-dimethylbutyl, 2,2-dimethylbutyl, 1,1 -dimethylbutyl, 2,3-dimethylbutyl, 1,3-dimethylbutyl or 1,2-dimethylbutyl, and the like or isomers thereof. For example, in some embodiments, R6, R7may each independently be selected from C1-C6alkyl, unsubstituted, R8and R9may each independently be selected from C1-C6alkyl, unsubstituted, such as methyl, ethyl, propyl, butyl, isopropyl, isobutyl, sec-butyl, tert-butyl.

[0084] The term "C2-C18alkenyl" is to be understood as meaning a straight-chain or branched, unsaturated hydrocarbon group having 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms, which contains one or more carbon-carbon double bonds (C=C) in its molecule.

[0085] The term "C2-C18alkynyl" is to be understood as meaning a straight-chain or branched, unsaturated hydrocarbon group having 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18 carbon atoms, which contains one or more carbon-carbon triple bonds (C≡C) in its molecule.

[0086] The term "C3-C18cycloalkyl" is to be understood as meaning saturated, monovalent, monocyclic or bicyclic hydrocarbon rings having from 3 to 18 carbon atoms, including fused or bridged polycyclic ring systems. Examples are cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl or cyclodecyl, or bicyclic hydrocarbyl groups such as decalin rings.

[0087] The term "5-18 membered heterocyclyl" is to be understood as meaning saturated, unsaturated or partially saturated monocyclic, bicyclic or tricyclic or tetracyclic rings having from 5 to 18 atoms in the ring, wherein the heteroatoms are selected from N, O and S, which can be attached via carbon or nitrogen, unless otherwise specified, wherein -CH 2- groups are optionally replaced by -C(O)-; and wherein, unless otherwise specified, a ring nitrogen atom or a ring sulfur atom is optionally oxidized to form an N-oxide or S-oxide, or a ring nitrogen atom is optionally quaternized; wherein -NH in the ring is optionally substituted by acetyl, formyl, methyl or methylsulfonyl; and the ring is optionally substituted by one or more halogen. It is to be understood that when the total number of S atoms and O atoms in the heterocyclyl group exceeds 1, these heteroatoms are not adjacent to each other. If the heterocyclyl group is bicyclic or tricyclic, at least one ring can optionally be heteroaromatic or aromatic, provided that at least one ring is non-heteroaromatic. If the heterocyclyl group is monocyclic, it must not be aromatic. Examples of heterocyclyl groups include, but are not limited to, piperidinyl, N-acetylpiperidinyl, N-methylpiperidinyl, N-formylpiperazinyl, N-methylsulfonylpiperazinyl, homopiperazinyl, piperazinyl, azetidinyl, oxetanyl, morpholinyl, tetrahydroisoquinolinyl, tetrahydroquinolinyl, dihydroindolyl, tetrahydropyranyl, dihydro-2H-pyranyl, tetrahydrofuranyl, tetrahydrothiopyranyl, tetrahydrothiopyran-1 -oxide, tetrahydrothiopyran-1,1 -dioxide, 1 H-pyridin-2-one and 2,5-dioxoimidazolidinyl. The term "C1-C18alkoxy" is to be understood as meaning -O-(C1-C18alkyl), wherein "C1-C18alkyl" has the same definition as above. The term "C6-C18aryl" is to be understood as meaning a monovalent aromatic or partially aromatic monocyclic or polycyclic hydrocarbon ring having from 6 to 18 carbon atoms, in particular a ring having 6 carbon atoms ("C6aryl"), such as phenyl; or a ring having 9 carbon atoms ("C9aryl"), such as indanyl or indenyl; or a ring having 10 carbon atoms ("C10aryl"), such as tetrahydronaphthyl, dihydronaphthyl or naphthyl. When the C6-C18aryl group is substituted, it can be mono- or polysubstituted. Also, there is no restriction on the substitution site, such as ortho, para or meta substitution. The term "C6-C30aryloxy" is to be understood as meaning -O-(C6-C30aryl). 10 The term "C6-C18aryl" is to be understood as meaning a monovalent aromatic or partially aromatic monocyclic or polycyclic hydrocarbon ring having from 6 to 18 carbon atoms, in particular a ring having 6 carbon atoms ("C6aryl"), such as phenyl; or a ring having 9 carbon atoms ("C9aryl"), such as indanyl or indenyl; or a ring having 10 carbon atoms ("C10aryl"), such as tetrahydronaphthyl, dihydronaphthyl or naphthyl. When the C6-C18aryl group is substituted, it can be mono- or polysubstituted. Also, there is no restriction on the substitution site, such as ortho, para or meta substitution. The term "C6-C30aryloxy" is to be understood as meaning -O-(C6-C30aryl).

[0088] The term "5-18-membered heteroaryl" should be understood as a monovalent monocyclic, bicyclic, or tricyclic aromatic ring group having 5-18 ring atoms and containing heteroatoms independently selected from N, O, and S. Furthermore, in each case, it may be a benzo[a]fused group. Specifically, the heteroaryl group is selected from thienyl, furanyl, pyrroleyl, oxazolyl, thiazolyl, imidazolyl, pyrazolyl, isoxazolyl, isothiazolyl, oxadiazolyl, triazolyl, thiadiazolyl, etc., and their benzo[derivatives], such as benzofuranyl, benzothienyl, benzooxazolyl, benzoisooxazolyl, benzoimidazolyl, benzotriazolyl, indazole, indolyl, isindolyl, etc.; or pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, etc., and their benzo[derivatives], such as quinolinyl, quinazolinyl, isoquinolinyl, etc.; or acrylinyl, inazinyl, purinyl, etc., and their benzo[derivatives]; or cyclolinyl, phthalazinyl, quinazolinyl, quinoxolinyl, naphthinyl, pteridinyl, carbazolyl, acrylinyl, phenazinyl, phenothiazinyl, phenothiazinyl, etc.

[0089] The terms "halogen" or "halogen" refer to fluorine, chlorine, bromine, and iodine.

[0090] The term "electron-withdrawing heterocyclic group" is defined as an electron-withdrawing group containing at least one of aromatic rings and aromatic heterocycles and containing heteroatoms. Here, "heteroatoms" can be located on or outside the aromatic ring or aromatic heterocycle. Here, "heteroatoms" can include at least one of O, N, S, and B atoms.

[0091] In one aspect of this disclosure, embodiments of this disclosure provide a compound having the structural formula (I):

[0092] X1 and X2 are each independently selected from one of O, S, Se, C=O, S(=O)2, CR6R7, SiR6R7, NR6, PR6, P(=O)R6, BR6; or X1 and X2 are either nonexistent or are direct connecting keys, and at most one of X1 and X2 is a direct connecting key.

[0093] X3 is selected from S, O, or CR8R9;

[0094] A1, A2, A3, A4, and A5 are each independently selected from unsubstituted or substituted C6-C18 aryl groups or 5-18 heteroaryl groups or unsubstituted or substituted with at least one substituent.

[0095] R1, R2, R3, R4, R5each independently represent 1 to 3 substituents each independently selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, unsubstituted or substituted with at least one substituent C1-C18alkyl, unsubstituted or substituted with at least one substituent C2-C18alkenyl, unsubstituted or substituted with at least one substituent C2-C18alkynyl, unsubstituted or substituted with at least one substituent C3-C18cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18alkoxy, unsubstituted or substituted with at least one substituent C6-C18aryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heteroaryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heterocyclyl; or the 1 to 3 substituents are arranged in such a way that they can bond with adjacent groups to form a 5- to 18-membered ring;

[0096] R6, R7each independently are selected from the group consisting of unsubstituted or substituted with at least one substituent C1-C18alkyl, unsubstituted or substituted with at least one substituent C2-C18alkenyl, unsubstituted or substituted with at least one substituent C2-C18alkynyl, unsubstituted or substituted with at least one substituent C3-C18cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18alkoxy, unsubstituted or substituted with at least one substituent C6-C18aryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heteroaryl, unsubstituted or substituted with at least one substituent 5- to 18-membered heterocyclyl; or R6, R7are arranged in such a way that they can bond with adjacent groups to form a 5- to 18-membered ring;

[0097] the substituents of the C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl;

[0098] R8and R9each independently are selected from the group consisting of unsubstituted or substituted with at least one substituent C1-C6alkyl, unsubstituted or substituted with at least one substituent C1-C6alkoxy;

[0099] or the substituents of the C1-C6alkyl, C1-C6alkoxy are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C18cycloalkyl, C1-C18alkoxy, C6-C18aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl;

[0100] L is a direct bond or a linking group selected from an oxygen atom, C1-C6-alkylene, which is unsubstituted or substituted by at least one substituent, C1-C6-alkyleneoxy, which is unsubstituted or substituted by at least one substituent, C6-C18-arylene, which is unsubstituted or substituted by at least one substituent, C6-C18-aryleneoxy, which is unsubstituted or substituted by at least one substituent, 5- to 18-membered heteroarylene, which is unsubstituted or substituted by at least one substituent, 5- to 18-membered heteroaryleneoxy, which is unsubstituted or substituted by at least one substituent;

[0101] the substituents of the C1-C6-alkylene, C1-C6-alkyleneoxy, C6-C18-arylene, C6-C18-aryleneoxy, 5- to 18-membered heteroarylene, 5- to 18-membered heteroaryleneoxy are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18-alkyl, C2-C18-alkenyl, C2-C18-alkynyl, C3-C18-cycloalkyl, C1-C18-alkoxy, C6-C18-aryl, 5- to 18-membered heteroaryl, 5- to 18-membered heterocyclyl;

[0102] A is an electron-withdrawing heterocyclic group having electron-transporting ability.

[0103] According to embodiments of the present disclosure, in the compound represented by formula (I):

[0104] X1and X2are each independently selected from one of O, S, Se, C=O, S(=O)2, CR6R7, SiR6R7, NR6, PR6, P(=O)R6, BR6; or X1and X2are absent or a direct bond, and at most one of X1, X2is a direct bond;

[0105] X3is selected from S, O or CR8R9;

[0106] A1, A2, A3, A4, A5are each independently selected from C6-C18-aryl, which is unsubstituted or substituted by at least one substituent, 5- to 18-membered heteroaryl, which is unsubstituted or substituted by at least one substituent;

[0107] R1, R2, R3, R4, R5each independently represent one to three substituents, each independently selected from hydrogen, halogen, C1-C18-alkyl, which is unsubstituted or substituted by at least one substituent, C6-C18-aryl, which is unsubstituted or substituted by at least one substituent, 5- to 18-membered heteroaryl, which is unsubstituted or substituted by at least one substituent, 5- to 18-membered heterocyclyl, which is unsubstituted or substituted by at least one substituent;

[0108] R6, R7are each independently selected from the group consisting of C1-C18alkyl, C6-C18aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl, each of which is unsubstituted or substituted with at least one substituent;

[0109] the substituents of the C1-C18alkyl, C6-C18aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12alkyl, C3-C12cycloalkyl, C1-C12alkoxy, C6-C18aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl;

[0110] R8and R9are each independently selected from the group consisting of C1-C6alkyl, C1-C6alkoxy, each of which is unsubstituted or substituted with at least one substituent;

[0111] the substituents of the C1-C6alkyl, C1-C6alkoxy are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12alkyl, C3-C12cycloalkyl, C1-C12alkoxy, C6-C18aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl;

[0112] L is a direct bond or a linking group selected from the group consisting of an oxygen atom, C1-C6alkylene, C6-C18arylene, C6-C18aryloxy, 5-18 membered heteroarylene, each of which is unsubstituted or substituted with at least one substituent;

[0113] or, the substituents of the C1-C6alkylene, C6-C18arylene, C6-C18aryloxy, 5-18 membered heteroarylene are selected from the group consisting of hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12alkyl, C3-C12cycloalkyl, C1-C12alkoxy, C6-C18aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl. According to embodiments of the present disclosure, in the compound of formula (I):

[0114] X1and X2are each independently selected from one of O, S, C=O, CR6R7, NR6, BR6; or X1and X2are absent or a direct bond, and at most one of X1, X2is a direct bond;

[0115] X3is selected from S, O or CR8R9;

[0116] A1, A2, A3, A4, A5are each independently selected from the group consisting of C6-C18aryl, 5-18 membered heteroaryl, each of which is unsubstituted or substituted with at least one substituent.

[0117] R1, R2, R3, R4, R5 each independently represents 1 to 3 substituents each independently selected from hydrogen, halogen, unsubstituted C1-C18 alkyl, unsubstituted C6-C18 aryl, unsubstituted 5-18 membered heteroaryl, unsubstituted 5-18 membered heterocyclyl;

[0118] R6, R7 each independently selected from unsubstituted C1-C18 alkyl, unsubstituted C6-C18 aryl, unsubstituted 5-18 membered heteroaryl, unsubstituted 5-18 membered heterocyclyl;

[0119] R8 and R9 each independently selected from unsubstituted C1-C6 alkyl, unsubstituted C1-C6 alkoxy;

[0120] L is a direct bond or a linking group selected from unsubstituted C1-C6 alkylene, unsubstituted C6-C18 arylene, unsubstituted C6-C18 aryloxy, unsubstituted 5-18 membered heteroarylene.

[0121] According to embodiments of the present disclosure, in the compound represented by formula (I):

[0122] R1, R2, R3, R4, R5 each independently represents 1 to 3 substituents each independently selected from hydrogen, unsubstituted C6-C18 aryl;

[0123] R6, R7 each independently selected from unsubstituted C1-C6 alkyl, unsubstituted C6-C12 aryl, unsubstituted 5-14 membered heteroaryl;

[0124] R8 and R9 each independently selected from unsubstituted C1-C6 alkyl;

[0125] L is a direct bond or a linking group selected from unsubstituted C1-C6 alkylene, unsubstituted C6-C18 arylene, unsubstituted C6-C18 aryloxy, unsubstituted 5-18 membered heteroarylene, wherein the heteroatom in the unsubstituted 5-18 membered heteroarylene is N.

[0126] It should be noted that there is no particular limitation on what group A is in the compound represented by formula (I), for example, it can be any chemical group that can be used as an acceptor group in the field of TADF materials, as long as it meets the requirement of being an electron-transporting electron-withdrawing heterocyclic group, and all such groups are covered within the protection scope of the compounds of the present disclosure.

[0127] According to embodiments of the present disclosure, in the compound represented by formula (I), A is selected from one of the following:

[0128] According to embodiments of the present disclosure, in the compound represented by formula (I), A is selected from one of the following:

[0129] wherein, in , Y1, Y2, Y3 are each independently selected from N, CH, and at least one is N; in , Y1, Y2 are each independently selected from N, CH, Y3 is selected from NH, O, CH2, and at least one of Y1, Y2, Y3 contains N atom;

[0130] n is any integer from 0 to 5;

[0131] R 10 , R 11 each independently represents 1 to 5 substituents each independently selected from hydrogen, substituted or unsubstituted C1-C18 alkyl, unsubstituted or substituted with at least one substituent C2-C18 alkenyl, unsubstituted or substituted with at least one substituent C2-C18 alkynyl, unsubstituted or substituted with at least one substituent C3-C18 cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18 alkoxy, unsubstituted or substituted with at least one substituent C1-C18 alkylthio, unsubstituted or substituted with at least one substituent amine, unsubstituted or substituted with at least one substituent C6-C30 arylthio, unsubstituted or substituted with at least one substituent C6-C30 aryloxy, unsubstituted or substituted with at least one substituent C6-C30 aryl, unsubstituted or substituted with at least one substituent 5-30 membered heteroaryl;

[0132] The substituents of the C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C1-C18 alkylthio, amine, C6-C30 arylthio, C6-C30 aryloxy, C6-C30 aryl, 5-30 membered heteroaryl are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 membered heteroaryl, 5-18 membered heterocyclyl.

[0133] According to embodiments of the present disclosure, R 10 , R 11each independently represents 1 to 5 substituents each independently selected from the group consisting of hydrogen, unsubstituted C1-C18 alkyl, unsubstituted C6-C30 aryl, and unsubstituted 5-30 membered heteroaryl.

[0134] According to an embodiment of the present disclosure, n is 1 or 2; R 10 , R 11 each independently represents 1 to 5 substituents each independently selected from the group consisting of hydrogen, unsubstituted C1-C10 alkyl, unsubstituted C6-C18 aryl, and unsubstituted 5-18 membered heteroaryl, wherein the heteroatom in the unsubstituted 5-18 membered heteroaryl is N, and when R 10 or R 11 is a substituent of a benzene ring, R 10 , R 11 each independently forms a fused ring with the benzene ring to which it is attached.

[0135] According to an embodiment of the present disclosure, the compound represented by formula (I) is any one of the following compounds:

[0136] According to an embodiment of the present disclosure, the compound includes a donor group and an acceptor group, the acceptor group is A in the compound represented by formula (I), and the donor group is the rest of the compound represented by formula (I) except -L-A,

[0137] The spatial distance between the center of the plane in which the donor group is located and the center of the plane in which the acceptor group is located is D, wherein D is not greater than 3.5 angstroms.

[0138] According to an embodiment of the present disclosure, the center of the plane in which the donor group is located refers to the center of the plane in which at least 5 atoms in the conjugated plane are selected as the center of the plane of the donor group;

[0139] The center of the plane in which the acceptor group is located refers to the center of the plane in which the conjugated ring structure is located, and the distance d1 from any conjugated atom in the conjugated ring structure to the center of the plane in which the donor group is located is not greater than 3.8 angstroms.

[0140] According to the embodiments of the present disclosure, the above-described TADF material molecules of the space-charge transfer type can be summarized as the model shown in FIG. 1. Specifically, on a rigid conjugated connecting group 13, a donor unit (donor group 11) and an acceptor unit (acceptor group 12) are fixed, and the spatial distance between the center of the plane where the donor group 11 is located and the center of the plane where the acceptor group 12 is located is D,

[0141] The center of the plane where the donor group is located is the center of the plane where at least 5 atoms on the conjugated plane in the donor group are located (including the electron-donating nitrogen atom in the structural formula (I)), and the center of the plane of the donor group is taken as the center of the plane;

[0142] The center of the plane where the acceptor group is located is the center of the plane where any selected conjugated ring structure in the acceptor group is located (in the selected conjugated ring structure, the distance between a conjugated atom and the center of the plane of the donor group is closer than the distance between other conjugated atoms in the acceptor group and the center of the plane of the donor group);

[0143] The spatial distance between the center of the plane where the donor group is located and the center of the plane where the acceptor group is located is D, and D is not greater than 3.5 angstroms;

[0144] The center of the plane where the acceptor group is located is the center of the plane where any selected conjugated ring structure in the acceptor group is located; and the distance d1 between any conjugated atom in the conjugated ring structure and the center of the plane where the donor group is located is not greater than 3.8 angstroms;

[0145] By limiting the plane centers of the donor group and the acceptor group within a smaller range, strong spatial attraction between the donor and the acceptor is achieved, the rate of space-charge transfer is fast, and the utilization rate of excitons in the light-emitting layer of the light-emitting material and the device is improved.

[0146] In another aspect, the embodiments of the present disclosure also provide the use of the compound as described above as a light-emitting material.

[0147] In another aspect, the embodiments of the present disclosure provide an organic electroluminescent device, which comprises a light-emitting layer, and the material of the light-emitting layer comprises the compound described above.

[0148] According to the embodiments of the present disclosure, the structure of the organic electroluminescent device provided by the embodiments of the present disclosure can be as shown in FIG. 2, which comprises a substrate 1, a first electrode 2, a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, a light-emitting layer 6, a hole blocking layer 7, an electron transport layer 8, an electron injection layer 9, and a second electrode 10 which are sequentially stacked.

[0149] According to the embodiments of the present disclosure, the first electrode can be a transparent electrode formed of an oxide such as ITO, IZO, or a composite electrode formed of ITO / Ag / ITO, Ag / IZO, CNT / ITO, CNT / IZO, etc.; and the second electrode can be a silver-magnesium composite electrode or an Al electrode. The organic electroluminescent device further includes a substrate 1 disposed on a side of the first electrode 2 distal from the second electrode 10, which can be formed of a transparent rigid or flexible material such as glass, polyimide, etc., and can realize rigid substrate display and flexible substrate display.

[0150] According to the embodiments of the present disclosure, the organic electroluminescent device provided by the embodiments of the present disclosure further includes a hole injection layer 3, a hole transport layer 4, an electron blocking layer 5, and a light-emitting layer 6 disposed in sequence on a side of the first electrode 2 (which can be an anode) proximal to the hole blocking layer 7; and an electron injection layer 9 disposed on a side of the electron transport layer 8 distal from the hole blocking layer 7.

[0151] According to the embodiments of the present disclosure, the material of the hole injection layer 3 can be an inorganic oxide such as an oxide of a metal such as molybdenum, titanium, vanadium, rhenium, ruthenium, chromium, zirconium, hafnium, tantalum, silver, tungsten, manganese, etc., or can be a dopant of a strong electron-withdrawing system such as 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyano-p-benzoquinone (F4TCNQ), HAT-CN, etc., or can be P-type doped with a hole transport material, and the thickness of the hole injection layer can be 5 nm to 30 nm.

[0152] According to the embodiments of the present disclosure, the material of the hole transport layer 4 has good hole transport characteristics, and can be an aromatic amine or carbazole material such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB), tris(4-carbazol-9-ylphenyl)amine (TCTA), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (TPD), 4-phenyl-4'-(9-phenylfluorene-9-yl)triphenylamine (BAFLP), 4,4'-bis[N-(9,9-dimethylfluorene-2-yl)-N-phenylamino]biphenyl (DFLDPBi), etc., and the thickness of the hole transport layer 4 can be 30 nm to 300 nm, for example, the thickness of the hole transport layer 4 can be 100 nm to 300 nm.

[0153] According to the embodiments of the present disclosure, the electron blocking layer 5, i.e. the light-emitting auxiliary layer, has hole transport characteristics, can be a red light-emitting auxiliary layer, a green light-emitting auxiliary layer, a blue light-emitting auxiliary layer, and the material of the light-emitting auxiliary layer can be an aromatic amine or carbazole material, such as mCP, 4,4'-bis(9-carbazolyl)biphenyl (CBP), 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (PCzPA), etc., and the thickness of the electron blocking layer 5 can be 5 nm to 50 nm.

[0154] According to the embodiments of the present disclosure, the material of the light-emitting layer 6 can include a red phosphorescent host material and a red phosphorescent dopant, a green phosphorescent host material and a green phosphorescent dopant, a blue phosphorescent host material and a blue phosphorescent dopant, or a fluorescent host material and a fluorescent dopant (for example, a compound provided in the above embodiments of the present disclosure), the host material of the light-emitting layer 6 can include one material or two or more mixed materials, wherein the host material of the blue light-emitting layer can be selected from anthracene derivatives, for example, N1,N6-di([1,1'-biphenyl]-2-yl)-N1,N6-di([1,1'-biphenyl]-4-yl)pyrene-1,6-diamine, 9,10-di-(2-naphthyl)anthracene (ADN), 2-methyl-9,10-di-2-naphthylanthracene (MADN), etc., and the guest material can be pyrene derivatives, fluorene derivatives, perylene derivatives, styrylamine derivatives, metal complexes, etc., such as 2,5,8,11-tetra-tert-butylperylene (TBPe), 4,4'-bis[4-(diphenylamino)styryl]biphenyl (BDAVBi), 4,4'-bis[4-(di-p-tolylamino)styryl]biphenyl (DPAVBi), bis(4,6-difluorophenylpyridine-C2,N)picolinate iridium (FIrpic), etc.; the host material of the green light-emitting layer can be selected from coumarin dyes, quinacridone copper derivatives, polycyclic aromatic hydrocarbons, anthracene derivatives, carbazole derivatives, such as N,N'-dimethylquinacridone (DMQA), N10,N10'-diphenyl-N10,N10'-dibenzoyl-9,9'-dianthracene-10,10'-diamine (abbreviated as: BA-NPB), tris(8-hydroxyquinoline)aluminum (III) (abbreviated as: Alq3), etc., and the guest material can be metal complexes, etc., such as tris(2-phenylpyridine)iridium (Ir(ppy)3), bis(2-phenylpyridine)iridium acetylacetonate (Ir(ppy)2(acac)), etc.; the host material of the red light-emitting layer can be selected from DCM series materials, such as 4-(dicyanomethylene)-2-methyl-6-(4-dimethylaminostyryl)-4H-pyran (DCM), 4-(dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljuglavidin-9-enyl)-4H-pyran (DCJTB), DCJTI, etc., and the guest material can be metal complexes, such as bis(1-phenylisoquinoline)(acetylacetonate)iridium (III) (Ir(piq)2(acac)), octaethylporphyrin platinum (abbreviated as: PtOEP), bis(2-(2'-benzothienyl)pyridine-N,C3')(acetylacetonate)iridium (abbreviated as: Ir(btp)2(acac)), etc., and the thickness of the light-emitting layer can be 20 nm to 100 nm.

[0155] The material of the light-emitting layer 6 in the organic electroluminescent device provided by the embodiments of the present disclosure further includes a compound represented by formula (I).

[0156] According to the embodiments of the present disclosure, the thickness of the hole blocking layer 7 can be 5 nm to 100 nm, the thickness of the electron transport layer 8 can be 20 nm to 100 nm, the hole blocking layer 7 and the electron transport layer 8 each independently comprise an aromatic heterocyclic compound, for example, a benzimidazole derivative, an imidazopyridine derivative, a benzimidazophenanthroline derivative, and other imidazole derivatives, and a pyrimidine derivative, a triazine derivative, and other azine derivatives, and a quinoline derivative, an isoquinoline derivative, a phenanthroline derivative, and other compounds containing a nitrogen-containing six-membered ring structure, and a compound having a phosphine oxide group as a substituent on the heterocycle, for example, 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (OXD-7), 3-(4-tert-butylphenyl)-4-phenyl-5-(4-biphenylyl)-1,2,4-triazole (TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (p-EtTAZ), bathophenanthroline (BPhen), 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP), DPEPO, TmPyPB, and the like.

[0157] According to the embodiments of the present disclosure, the thickness of the electron injection layer 9 can be 1 nm to 10 nm, and the material of the electron injection layer 9 can be an alkali metal or a metal or a compound of an alkali metal or a metal, for example, LiF, Yb, Mg, Ca, or a compound thereof, and the like.

[0158] According to the embodiments of the present disclosure, the structure of the organic electroluminescent device provided by the embodiments of the present disclosure can be: substrate / first electrode (ITO) / hole injection layer (5 nm) / hole transport layer (30 nm) / electron blocking layer (10 nm) / emitting layer (20 nm) / hole blocking layer (5 nm) / electron transport layer (40 nm) / electron injection layer (1.5 nm) / second electrode (100 nm).

[0159] The solutions of the present disclosure will be explained below in conjunction with the examples. Those skilled in the art will understand that the examples below are only for illustrating the present disclosure and should not be considered as limiting the scope of the present disclosure. If a specific technique or condition is not specified in the examples, the technique or condition described in the literature in the art or according to the product manual is used. If the manufacturer of the reagent or instrument is not specified, it is a conventional product that can be obtained on the market.

[0160] Example 1: Synthesis of Intermediate 1

[0161] Into a 200 mL pressure tube, 4-bromodibenzofuran (2.56 g, 10 mmol), 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine (4.35 g, 10 mmol), Pd(PPh3)4(0.58 g, 0.5 mmol), potassium carbonate (4.14 g, 30 mmol) and THF / H2O (45 mL / 15 mL) were added, heated to 100 °C under argon protection for 12 h. TLC thin plate was used to monitor the reaction until it was completed. The reaction solution was spin dried, silica gel powder was added to adsorb the sample, and then separated by silica gel column chromatography. The solvent was spin dried to obtain a solid powder (4.04 g). Intermediate 1 was obtained with a yield of 85%.

[0162] Example 2: Synthesis of Intermediate 2

[0163] The synthesis of Intermediate 2 was similar to that of Intermediate 1, except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine was replaced by 4-(phenylcarbonyl)phenylboronic acid pinacol ester. The yield was 84%.

[0164] Example 3: Synthesis of Intermediate 3

[0165] The synthesis of Intermediate 3 was similar to that of Intermediate 1, except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine was replaced by 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-benzene-1,3-dicarbonitrile. The yield was 80%.

[0166] Example 4: Synthesis of Intermediate 4

[0167] The synthesis of Intermediate 4 was similar to that of Intermediate 1, except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-1,3,5-triazine was replaced by 4,4,5,5-tetramethyl-2-(4-(phenylsulfonyl)phenyl)-1,3,2-dioxaborolane. The yield was 81%.

[0168] Example 5: Synthesis of Intermediate 5

[0169] The synthesis of Intermediate 5 is similar to that of Intermediate 1 except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl]-l,3,5-triazine is replaced by 2-([l,l'-biphenyl]-3-yl)-5-(4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl)-l,3,4-oxadiazole. Yield 79%.

[0170] Example 6: Synthesis of Intermediate 6

[0171] The synthesis of Intermediate 6 is similar to that of Intermediate 1 except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl]-l,3,5-triazine is replaced by 2-([l,l'-biphenyl]-4-yl)-5-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-l,3,4-oxadiazole. Yield 80%.

[0172] Example 7: Synthesis of Intermediate 7

[0173] The synthesis of Intermediate 7 is similar to that of Intermediate 1 except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl]-l,3,5-triazine is replaced by 7-(6-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)pyridin-3-yl)-4a,9a,13a,13c-tetrahydro-13b-boronaphtho[3,2,l-de]anthracene-5,9-dione. Yield 75%.

[0174] Example 8: Synthesis of Intermediate 8

[0175] The synthesis of Intermediate 8 is similar to that of Intermediate 1 except that 2,4-diphenyl-6-[4-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)phenyl]-l,3,5-triazine is replaced by 7-(4,4,5,5-tetramethyl-l,3,2-dioxaborolan-2-yl)-4a,9a,13a,13c-tetrahydro-5,9-dioxa-13b-boronaphtho[3,2,l-de]anthracene. Yield 76%.

[0176] Example 9: Synthesis of Compound 43

[0177] The intermediate 1 obtained from example 1 (4.0 g, 8.42 mmol) was dissolved in 40 mL of dry tetrahydrofuran in a two-necked flask under argon atmosphere and cooled to -78°C for 10 min. n-BuLi (1.6 mol / L in THF, 8 mL) was added slowly by syringe and stirred at -78°C for 1 h. 10-phenylacridone (2.5 g, 9.26 mmol) was dissolved in dry tetrahydrofuran and added to the flask. The reaction was stirred at room temperature for 24 h under argon atmosphere. TLC monitoring was performed until the reaction was complete. Acetic acid (80 mL) and concentrated hydrochloric acid (10 mL) were added to the flask and the reaction was refluxed at 120°C under nitrogen atmosphere. TLC monitoring was performed until the reaction was complete. The reaction was cooled to room temperature, dried and extracted with dichloromethane. The organic phase was washed with water, dried over anhydrous sodium sulfate, dried and adsorbed with silica gel powder. The compound 43 was obtained as a white solid powder (4.70 g) with a yield of 76%.

[0178] Example 10: Synthesis of compound 2

[0179] The synthesis of compound 2 was similar to that of compound 43, except that intermediate 1 was replaced by intermediate 2 obtained from example 2. The yield was 75%.

[0180] Example 11: Synthesis of compound 4

[0181] The synthesis of compound 4 was similar to that of compound 43, except that intermediate 1 was replaced by intermediate 3 obtained from example 3. The yield was 75%.

[0182] Example 12: Synthesis of compound 44

[0183] The synthesis of compound 44 was similar to that of compound 43, except that 10-phenylacridone was replaced by indolo[3,2,1-DE]acridin-8-one. The yield was 75%.

[0184] Example 13: Synthesis of compound 13

[0185] The synthesis of compound 13 was similar to that of compound 43, except that intermediate 1 was replaced by intermediate 4 obtained from example 4 and 10-phenylacridone was replaced by indolo[3,2,1-DE]acridin-8-one. The yield was 75%.

[0186] Example 14: Synthesis of compound 62

[0187] The synthesis of compound 62 is similar to that of compound 43, except that intermediate 1 is replaced by intermediate 5 from Example 5, and 10-phenylacridone is replaced by 9H-spiro[fluorene-9,5'-quinoline[3,2,1-de]acridin]-9'-one, to synthesize compound 62. Yield 70%.

[0188] Example 15: Synthesis of compound 63

[0189] The synthesis of compound 63 is similar to that of compound 43, except that intermediate 1 is replaced by intermediate 6 from Example 6, and 10-phenylacridone is replaced by 9H-spiro[quinoline[3,2,1-de]acridine-5,9'-xanthen]-9-one (Spiro[1-azapentacyclo[11.7.1.02,7.09,21.015,20]henicosa-2,4,6,9(21),10,12,15,17,19-nonaene-14,9'-xanthene]-8-one), to synthesize compound 63. Yield 75%.

[0190] Example 16: Synthesis of compound 75

[0191] The synthesis of compound 75 is similar to that of compound 43, except that intermediate 1 is replaced by intermediate 7 from Example 7, and 10-phenylacridone is replaced by 8,8,12,12-tetramethyl-8,12-dihydro-4H-benzo[9,1]quinolizino[3,4,5,6,7-defg]acridin-4-one, to synthesize compound 75. Yield 75%.

[0192] Example 17: Synthesis of compound 29

[0193] The synthesis of compound 29 is similar to that of compound 43, except that intermediate 1 is replaced by intermediate 8 from Example 8, and 10-phenylacridone is replaced by indolo[3,2,1-de]acridine-8-one, to synthesize compound 29. Yield 75%.

[0194] Example 18: Synthesis of compound 97

[0195] The synthesis of compound 97 is similar to that of compound 43, except that intermediate 1 is replaced by intermediate 8 obtained in example 8, and 10-phenylacridanone is replaced by starting material A (8-Phenyl-1-aza-8-borapentacyclo[11.7.1.02,7.09,21.015,20]henicosa-2,4,6,9(21),10,12,15,17,19-nonaen-14-one), to synthesize compound 97. Yield 75%.

[0196] Evaluation of the chemical properties of compounds 43, 2, 4, 44, 13, 62, 63, 75, 29, 97

[0197] Some performance parameters of compounds 43, 2, 4, 44, 13, 62, 63, 75, 29, 97 prepared in the embodiments of the present disclosure were determined: the HOMO / LUMO energy levels of the compounds of the embodiments of the present disclosure were calculated using the results of AC-3 & CV & UV spectrum tests, and the data of the HOMO / LUMO energy levels are shown in Table 1 and Figure 3.

[0198] Table 1

[0199] The results of the above Table 1 show that the compounds obtained in the embodiments of the present disclosure all have TADF characteristics, for example, the energy difference (ΔE ST ) between the singlet state and the triplet state is small, and the HOMO and LUMO orbitals have an electron cloud overlap in space, and have certain application potential when used as a dopant or a sensitizing material for the light-emitting layer of an OLED device.

[0200] Preparation and performance of OLED devices

[0201] A device 1-1 was prepared using a comparative compound Ref. as a light-emitting layer guest material, and device embodiments were prepared using some compounds as light-emitting layer dopants and having the following structures. The structures of the light-emitting device embodiments are shown below:

[0202] ITO / HAT-CN (5 nm) / NPB (30 nm) / TCTA (10 nm) / mCP (10 nm) / compound (10 wt%): light-emitting layer HOST (20 nm) / DPEPO (5 nm) / TmPyPB (40 nm) / LiF (1.5 nm) / Ag:Mg (100 nm, doping ratio 10:1).

[0203] The ITO thin layer on the glass substrate is used as an anode, HAT-CN is used as a hole injection layer, NPB and TCTA are used as hole transport layers, mCP is used as an electron blocking layer, DPEPO is used as a hole blocking layer, TmPyPB is used as an electron transport layer, LiF is used as an electron injection layer, Ag:Mg is used as a cathode, and DPEPO is used as a light-emitting host material HOST. The molecular structures of the functional layer materials used are as follows:

[0204] The OLED device performance is shown in Table 2:

[0205] Table 2

[0206] As can be seen from Table 2, the compound obtained by the embodiment of the present disclosure is a blue TADF material with good device performance, and the OLED device using it as a light-emitting layer dopant all shows high efficiency, low driving voltage, and long service life.

[0207] Preparation and performance of the evaporated device

[0208] An evaporated device is prepared using the compound of the present disclosure and the comparative compound (Ref.) as the light-emitting layer sensitizer.

[0209] mCP is used as the light-emitting layer host material, (BTP)2Ir(acac) (which can also be written as Ir(btp)2(acac)) (chemical formula as follows) is used as the light-emitting layer guest material, compound 43, 2, 4, 44, 13, 62, 63, 75, 29, 97, and the comparative compound (Ref.) are used as the sensitizer, the mass ratio of mCP, the compound, and the iridium complex (BTP)2Ir(acac) is 79:20:1, vacuum evaporation is performed, and the total deposition is performed on the exciton / electron blocking layer, the thickness of the deposited thin film is 20 nm, and thus the light-emitting layer is formed.

[0210] The structure of the evaporated device is as follows:

[0211] ITO / HAT-CN (5 nm) / NPB (30 nm) / TCTA (10 nm) / mCP: compound: (BTP)2Ir(acac) (20 nm) / TmPyPB (40 nm) / LiF (1.5 nm) / Ag:Mg (100 nm, doping ratio is 10:1).

[0212] The ITO thin layer on the glass substrate is used as an anode, HAT-CN is used as a hole injection layer, NPB and TCTA are used as hole transport layers, mCP is used as a host, TmPyPB is used as an electron transport layer / LiF is used as an electron injection layer, and Ag:Mg is used as a cathode. The structure of (BTP)2Ir(acac) is as follows:

[0213] The prepared electroluminescent device partial performance is shown in Table 3:

[0214] Table 3

[0215] As can be seen from Table 3, the compound of the embodiment of the present disclosure is a TADF material with good device performance, and the OLED device using it as the sensitizing material of the light-emitting layer shows high efficiency, low driving voltage and long service life electroluminescent performance.

[0216] In the description of the present specification, the description referring to the terms "one embodiment", "some embodiments", "an example", "a specific example", "some implementations" or "some examples" and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the present specification and the features of the different embodiments or examples without contradiction.

[0217] Although the embodiments of the present disclosure have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present disclosure, and the person skilled in the art can make changes, modifications, replacements and variations to the above embodiments within the scope of the present disclosure.

Claims

1. A compound having the structural formula (I): in, X1 and X2 are each independently selected from one of O, S, Se, C=O, S(=O)2, CR6R7, SiR6R7, NR6, PR6, P(=O)R6, BR6; or X1 and X2 are either nonexistent or are direct connecting keys, and at most one of X1 and X2 is a direct connecting key; X3 is selected from S, O, or CR8R9; A1, A2, A3, A4, and A5 are each independently selected from unsubstituted or substituted C6-C18 aryl groups or 5-18 heteroaryl groups or unsubstituted or substituted with at least one substituent. R1, R2, R3, R4, and R5 each independently represent one to three substituents, wherein each of the one to three substituents is independently selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, unsubstituted or substituted with at least one substituent C1-C18 alkyl, unsubstituted or substituted with at least one substituent C2-C18 alkenyl, unsubstituted or substituted with at least one substituent C2-C18 alkynyl, unsubstituted or substituted with at least one substituent C3-C18 cycloalkyl, unsubstituted or substituted with at least one substituent C1-C18 alkoxy, unsubstituted or substituted with at least one substituent C6-C18 aryl, unsubstituted or substituted with at least one substituent 5-18 heteroaryl, unsubstituted or substituted with at least one substituent 5-18 heterocyclic; or, the 1 One to three substituents are configured to combine with adjacent groups to form a 5-18 membered ring; R6 and R7 are each independently selected from unsubstituted or substituted C1-C18 alkyl, unsubstituted or substituted C2-C18 alkenyl, unsubstituted or substituted C2-C18 alkynyl, unsubstituted or substituted C3-C18 cycloalkyl, unsubstituted or substituted C1-C18 alkoxy, unsubstituted or substituted C6-C18 aryl, unsubstituted or substituted 5-18 heteroaryl, unsubstituted or substituted 5-18 heterocyclic group; or, R6 and R7 are configured to combine with adjacent groups to form a 5-18 membered ring; The substituents of the C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups. R8 and R9 are each independently selected from unsubstituted or substituted C1-C6 alkyl groups or unsubstituted or substituted C1-C6 alkoxy groups; Alternatively, the substituents of the C1-C6 alkyl and C1-C6 alkoxy groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups; L is a direct linking bond or linking group, wherein the linking group is selected from oxygen atom, unsubstituted or substituted C1-C6 alkylene group, unsubstituted or substituted C1-C6 alkene group, unsubstituted or substituted C6-C18 arylene group, unsubstituted or substituted C6-C18 arylene group, unsubstituted or substituted 5-18 heteroarylene group, and unsubstituted or substituted 5-18 heteroarylene group. The substituents of the C1-C6 alkylene, C1-C6 alkoxyene, C6-C18 arylene, C6-C18 arylene, 5-18 heteroarylene, and 5-18 heteroarylene are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 heteroarylene, and 5-18 heterocyclic groups. A is an electron-withdrawing heterocyclic group with electron transport capabilities.

2. The compound according to claim 1, wherein, X1 and X2 are each independently selected from one of O, S, Se, C=O, S(=O)2, CR6R7, SiR6R7, NR6, PR6, P(=O)R6, BR6; or X1 and X2 are either nonexistent or are direct connecting keys, and at most one of X1 and X2 is a direct connecting key; X3 is selected from S, O, or CR8R9; A1, A2, A3, A4, and A5 are each independently selected from unsubstituted or substituted C6-C18 aryl groups or 5-18 heteroaryl groups or unsubstituted or substituted with at least one substituent. R1, R2, R3, R4, and R5 each independently represent one to three substituents, wherein each of the one to three substituents is independently selected from hydrogen, halogen, unsubstituted or substituted C1-C18 alkyl, unsubstituted or substituted C6-C18 aryl, unsubstituted or substituted 5-18 heteroaryl, and unsubstituted or substituted 5-18 heterocyclic group. R6 and R7 are each independently selected from unsubstituted or substituted C1-C18 alkyl groups, unsubstituted or substituted C6-C18 aryl groups, unsubstituted or substituted 5-18 heteroaryl groups, and unsubstituted or substituted 5-18 heterocyclic groups. Alternatively, the substituents of the C1-C18 alkyl, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups; R8 and R9 are each independently selected from unsubstituted or substituted C1-C6 alkyl groups or unsubstituted or substituted C1-C6 alkoxy groups; The substituents of the C1-C6 alkyl and C1-C6 alkoxy groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups. L is a direct linking bond or a linking group, wherein the linking group is selected from oxygen atoms, unsubstituted or substituted C1-C6 alkylene groups, unsubstituted or substituted C6-C18 arylene groups, unsubstituted or substituted C6-C18 aryleneoxy groups, and unsubstituted or substituted 5-18 heteroarylene groups. The substituents of the C1-C6 alkylene, C6-C18 arylene, C6-C18 aryleneoxy, and 5-18 heteroarylene groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C12 alkyl, C3-C12 cycloalkyl, C1-C12 alkoxy, C6-C18 aryl, 5-18 heteroaryl, and 5-18 heterocyclic groups.

3. The compound according to claim 1 or 2, wherein, X1 and X2 are each independently selected from one of O, S, C=O, CR6R7, NR6, BR6; or X1 and X2 are either nonexistent or direct connection keys, and at most one of X1 and X2 is a direct connection key; X3 is selected from S, O, or CR8R9; A1, A2, A3, A4, and A5 are each independently selected from unsubstituted C6-C18 aryl groups and unsubstituted 5-18 heteroaryl groups; R1, R2, R3, R4, and R5 each independently represent one to three substituents, wherein each of the one to three substituents is independently selected from hydrogen, halogen, unsubstituted C1-C18 alkyl, unsubstituted C6-C18 aryl, unsubstituted 5-18 heteroaryl, and unsubstituted 5-18 heterocyclic group. R6 and R7 are each independently selected from unsubstituted C1-C18 alkyl groups, unsubstituted C6-C18 aryl groups, unsubstituted 5-18 membered heteroaryl groups, and unsubstituted 5-18 membered heterocyclic groups. R8 and R9 are each independently selected from unsubstituted C1-C6 alkyl groups and unsubstituted C1-C6 alkoxy groups; L is a direct linking bond or linking group, wherein the linking group is selected from unsubstituted C1-C6 alkylene, unsubstituted C6-C18 arylene, unsubstituted C6-C18 aryleneoxy, and unsubstituted 5-18 heteroarylene.

4. The compound according to any one of claims 1 to 3, wherein, R1, R2, R3, R4, and R5 each independently represent one to three substituents, wherein each of the one to three substituents is independently selected from hydrogen and unsubstituted C6-C18 aryl groups; R6 and R7 are each independently selected from unsubstituted C1-C6 alkyl groups, unsubstituted C6-C12 aryl groups, and unsubstituted 5-14 heteroaryl groups. R8 and R9 are each independently selected from unsubstituted C1-C6 alkyl groups; L is a direct linking bond or linking group, wherein the linking group is selected from unsubstituted C1-C6 alkylene, unsubstituted C6-C18 arylene, unsubstituted C6-C18 aryloxy, and unsubstituted 5- to 18-membered heteroarylene, wherein the heteroatom in the unsubstituted 5- to 18-membered heteroarylene is N.

5. The compound according to any one of claims 1 to 4, wherein, A is selected from triazine and its derivatives, benzophenone and its derivatives, diphenyl sulfone and its derivatives, oxadiazole and its derivatives, bipyridine and its derivatives, phenyl nitrile and its derivatives, or boron heterocyclic acceptors and their derivatives.

6. The compound according to any one of claims 1 to 4, wherein, A is selected from one of the following: Among them, In the above, Y1, Y2, and Y3 are each independently selected from N and CH, and at least one of them is N; In this context, Y1 and Y2 are each independently selected from N and CH, and Y3 is selected from NH, O, and CH2, and at least one of Y1, Y2, and Y3 contains an N atom; n is any integer from 0 to 5; R 10 R 11 Each of the following groups independently represents one to five substituents, each of which is independently selected from hydrogen, substituted or unsubstituted C1-C18 alkyl, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, C1-C18 alkylthio, unsubstituted or substituted with at least one substituent, unsubstituted or substituted with at least one substituent, C6-C30 arylthio, unsubstituted or substituted with at least one substituent, C6-C30 aryl, unsubstituted or substituted with at least one substituent, and 5-30 membered heteroaryl groups. The substituents of the C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C1-C18 alkylthio, amino, C6-C30 arylthio, C6-C30 aryloxy, C6-C30 aryl, and 5-30 heterocyclic groups are selected from hydrogen, deuterium, halogen, cyano, nitro, hydroxyl, C1-C18 alkyl, C2-C18 alkenyl, C2-C18 alkynyl, C3-C18 cycloalkyl, C1-C18 alkoxy, C6-C18 aryl, 5-18 heterocyclic, and 5-18 heterocyclic groups.

7. The compound according to claim 6, wherein, R 10 R 11 Each of the following groups independently represents one to five substituents, each of which is independently selected from hydrogen, unsubstituted C1-C18 alkyl groups, unsubstituted C6-C30 aryl groups, and unsubstituted 5-30 heteroaryl groups.

8. The compound according to claim 6 or 7, wherein, n is 1 or 2; R 10 R 11 Each of the five substituents independently represents one to five substituents, each of which is independently selected from hydrogen, unsubstituted C1-C10 alkyl groups, unsubstituted C6-C18 aryl groups, and unsubstituted 5-18-membered heteroaryl groups, wherein the heteroatom in the unsubstituted 5-18-membered heteroaryl groups is N. And when R 10 or R 11 When R is a substituent of the benzene ring, 10 R 11 Each ring independently forms a fused ring with the benzene ring it is attached to.

9. The compound according to any one of claims 1 to 8, wherein, The compound represented by formula (I) is any of the following compounds:

10. The compound according to any one of claims 1 to 9, comprising a donor group and an acceptor group, wherein the acceptor group is A in the compound of formula (I), and the donor group is the remainder of the compound of formula (I) except for -LA. The spatial distance between the center of the plane containing the donor group and the center of the plane containing the acceptor group is D, where D is not greater than 3.5 angstroms.

11. The compound according to claim 10, wherein, The center of the plane where the donor group is located refers to the center of the plane containing at least 5 atoms on the conjugated plane of the donor group, which is taken as the center of the plane of the donor group. The center of the plane containing the acceptor group refers to the distance d1 from any conjugated atom in any conjugated ring structure of the acceptor group to the center of the plane containing the donor group, which is no greater than 3.8 angstroms. The center of the plane containing the conjugated ring structure is taken as the center of the plane containing the acceptor group.

12. Use of the compound according to any one of claims 1 to 11 as a luminescent material.

13. An organic electroluminescent device, comprising a light-emitting layer, wherein the material of the light-emitting layer comprises any one of the compounds of claims 1 to 11.

14. A display panel comprising a light-emitting unit, the light-emitting unit comprising a light-emitting layer, the material of the light-emitting layer comprising any one of claims 1 to 11.

15. A display device comprising the display panel of claim 14.

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