An electroluminescent device that can improve luminous efficiency and lifespan

Abstract

This disclosure relates to an electroluminescent device that can improve luminous efficiency and lifetime. The electroluminescent device employs compounds of Formula 1 in all multiple organic layers, thereby simplifying the synthesis process of organic compounds and reducing synthesis costs. Furthermore, at least three of the at least four organic layers are adjacent. Since these deuterated naphthyl compounds have the same principal structure, the HOMO-LUMO energy level difference for hole or electron transport between these at least three organic layers can be significantly reduced, thereby reducing interface effects and facilitating the injection of electrons and / or holes. The presence of deuterium atoms in the structure improves molecular stability, thus increasing device lifetime, luminous efficiency, and reducing voltage. The deuterium-containing CPL material structure further enhances molecular stability, preventing capping layer failure and device efficiency reduction caused by degradation due to diffusion of metal ions from adjacent inorganic layers of the CPL.

Description

Technical Field

[0001] This disclosure belongs to the field of organic electroluminescent materials technology, specifically relating to an electroluminescent device that can improve luminous efficiency and lifetime. Background Technology

[0002] In recent years, organic electroluminescent devices (OLEDs) have gradually come into view as a new generation of display technology. A typical OLED consists of an anode, a cathode, and one or more organic layers placed between the cathode and anode. When a voltage is applied to the anode and cathode, an electric field is generated. Under the influence of this electric field, electrons on the cathode side move towards the OLED layer, and holes on the anode side also move towards the OLED layer. These electrons combine in the OLED layer to form excitons. The excitons, in an excited state, release energy outwards. The process of the excitons changing from the excited state to the ground state and releasing energy again emits light.

[0003] To improve the brightness, efficiency, and lifetime of organic electroluminescent devices (OLEDs), multilayer structures are typically used. These multilayer structures include: hole injection layer (HIL), hole transport layer (HTL), electron-blocking layer (EBL), emitting layer (EL), and electron transport layer (ETL), etc. These organic layers have the ability to improve the injection efficiency of charge carriers (holes and electrons) at the interfaces between layers and to balance the transport of charge carriers between layers, thereby improving the brightness and efficiency of the device.

[0004] The increasing demands on high-performance organic electroluminescent materials due to multilayer structures have led to the development of numerous high-performance organic electroluminescent materials. Overall, the future direction of organic electroluminescent devices lies in developing high-efficiency, long-lifetime, and low-cost white light devices and full-color display devices; however, the industrialization of this technology still faces many key challenges.

[0005] Therefore, designing and finding stable and efficient compounds as novel materials for organic electroluminescent devices to overcome their shortcomings in practical applications is a key focus and future research trend in organic electroluminescent device materials research. Summary of the Invention

[0006] This disclosure presents a structure for an organic electroluminescent device. By designing the device structure, a device structure combination that can be used to improve light extraction efficiency is obtained.

[0007] This disclosure provides an organic electroluminescent device comprising at least four organic layers, wherein at least three of the four organic layers are adjacent organic layers between the cathode and the anode, and each contains a compound having the structure shown in Formula 1 below:

[0008]

[0009] Among them, one of X1 to X8 is a site attached to the main structure of the compound, and the other seven are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1 to C40 alkyl, substituted or unsubstituted C6 to C60 aromatic amino, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted 3 to 60 heteroaryl, substituted or unsubstituted C3 to C60 aryl, and at least one contains a deuterium atom.

[0010] In some embodiments, the structure shown in Equation 1 is as shown in Equation 1-1 or 1-2:

[0011]

[0012] X2 to X8 are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1 to C40 alkyl, substituted or unsubstituted C6 to C60 aromatic amino, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted C3 to C60 aryl, and at least one contains a deuterium atom;

[0013]

[0014] X1 to X7 are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1 to C40 alkyl, substituted or unsubstituted C6 to C60 aromatic amino, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted C3 to C60 aryl, and at least one contains a deuterium atom.

[0015] In some embodiments, in the structure shown in Formula 1-1, X2, X5, X7, and X8 are each independently selected from hydrogen and deuterium, X3 and X4 are deuterium, and X6 is selected from hydrogen, deuterium, and phenyl; in the structure shown in Formula 1-2, X1, X2, X5, and X7 are each independently selected from hydrogen and deuterium, X3 and X4 are deuterium, and X6 is selected from hydrogen, deuterium, and phenyl.

[0016] In some embodiments, the structure shown in Formula 1 is selected from the following structures:

[0017]

[0018] In some embodiments, the at least four organic layers are a light-emitting layer, an electron-blocking layer, a hole-blocking layer, and a light-emitting layer, wherein the light-emitting layer, the electron-blocking layer, and the hole-blocking layer are adjacent to each other; the light-emitting layer is disposed on the side of the cathode away from the anode.

[0019] In some embodiments, the host material comprising the light-emitting layer has the structure shown in Formula A:

[0020]

[0021] R1 and R2 are each independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic.

[0022] Y is either O or S;

[0023] m is an integer from 0 to 7, for example, 0, 1, 2, 3, 4, 5, 6, 7; n is an integer from 0 to 8, for example, 0, 1, 2, 3, 4, 5, 6, 7, 8; in particular, m is 0 or 1, and n is 0;

[0024] L1 and L2 are each independently directly bonded, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, and carbazolylene;

[0025] Equation 1 is selected from Equation 1 above.

[0026] In some embodiments, in the structure shown in Formula A, R2 is selected from deuterium and phenyl, Y is O or S, m is 0 or 1, n is 0, and L1 and L2 are each independently direct-bonded, phenylene or biphenylene.

[0027] In some embodiments, the structure shown in Formula A is selected from the following structures:

[0028]

[0029] Among them, R1, R2, Y, m, n, L1, L2 and Equation 1 are as defined in Equation A above.

[0030] In some embodiments, the structure shown in Formula A is selected from the following structures:

[0031]

[0032]

[0033] In some embodiments, the structure shown in formula A is

[0034] In some embodiments, the electron blocking layer comprises a material having the structure shown in Formula B:

[0035]

[0036] R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group;

[0037] R2 is selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclol.

[0038] Y is either O or S;

[0039] m is an integer from 0 to 7, for example, 0, 1, 2, 3, 4, 5, 6, 7; in particular, m is 0 or 1;

[0040] L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolylene;

[0041] Equation 1 is selected from Equation 1 above.

[0042] In some embodiments, in the structure shown in Formula B, R1 is selected from the structure shown in Formula 1 above, phenanthrene, biphenyl, Y is O or S, m is 0 or 1, R2 is selected from deuterium and phenyl, L1 and L2 are each independently directly bonded or phenylene, and L3 is phenylene.

[0043] In some embodiments, the structure shown in Formula B is selected from the following structures:

[0044]

[0045] Among them, R1, R2, Y, m, L1, L2, L3 and Equation 1 are as defined in Equation B above.

[0046] In some embodiments, the structure shown in Formula B is selected from the following structures:

[0047]

[0048] In some embodiments, the structure shown in equation B is

[0049] In some embodiments, the hole-blocking layer comprises a material having the structure shown in Formula C:

[0050]

[0051] R1 and R2 are each independently selected from substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups, or substituted or unsubstituted heterocyclic groups;

[0052] L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolyl;

[0053] Equation 1 is selected from Equation 1 above.

[0054] In some embodiments, in the structure shown in formula C,

[0055] R1 is

[0056] R2 is selected from the structure shown in Formula 1 above, biphenyl, phenyl, phenanthrene,

[0057] L1 is a phenylene oxide;

[0058] L2 and L3 are each independently directly bonded or phenylene.

[0059] In some embodiments, the structure shown in Formula C is selected from the following structures:

[0060]

[0061] Among them, R2, L1, L2, L3 and Equation 1 are as defined in Equation C above.

[0062] In some embodiments, the structure shown in Formula C is selected from the following structures:

[0063]

[0064]

[0065] In some embodiments, the structure shown in Formula C is selected from:

[0066] and

[0067] In some embodiments, the light-emitting layer comprises a material having the structure shown in formula D:

[0068]

[0069] R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group;

[0070] R2 is independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted heterocycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclol.

[0071] Y is either O or S;

[0072] m is an integer from 0 to 7; for example, 0, 1, 2, 3, 4, 5, 6, 7; in particular, m is either 0 or 1.

[0073] L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolyl;

[0074] A semi-circular shape indicates that there is a fused or unfused aromatic or non-aromatic ring at that location, such as a benzene ring, a naphthyl ring, a benzofuran ring, a benzothiophene ring, a norbornene ring, etc.

[0075] Equation 1 is selected from Equation 1 above.

[0076] In some embodiments, in the structure shown in Formula D, R1 is a benzo-substituted or unsubstituted heteroaryl group (e.g., thieno-thienoyl, benzoxazolyl); Y is O or S; m is 0; L1 is phenylene; L2 and L3 are each independently directly bonded or phenylene.

[0077] In some embodiments, the structure shown in Formula D is selected from the following structures:

[0078]

[0079] Among them, R1, R2, Y, m, L1, L2, L3 and Equation 1 are as defined in Equation D above.

[0080] In some embodiments, the structure shown in Formula D is selected from the following structures:

[0081]

[0082] In some embodiments, the structure shown in formula D is selected from:

[0083] and

[0084] In some embodiments, the organic electroluminescent device disclosed herein includes an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, a cathode, and a light-emitting layer.

[0085] The organic electroluminescent device according to this disclosure can have the structure of a conventional organic electroluminescent device without particular limitation. For example, the organic electroluminescent device can have a structure of anode / hole injection layer / hole transport layer / electron blocking layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode / light emitting layer, but is not limited thereto.

[0086] Except that at least four organic layers, such as an electron blocking layer, a light-emitting layer, a hole blocking layer, and a light-emitting layer, comprise the compounds having the structure shown in Formula 1, the organic electroluminescent device according to this disclosure can be fabricated using conventional materials. In some embodiments, the organic electroluminescent device according to this disclosure may include two light-emitting layers, one of which comprises the compounds having the structure shown in Formula 1, and the other of which can be fabricated using conventional materials.

[0087] In some embodiments, the material of the hole injection layer may be selected from, but is not limited to, inorganic oxides, p-type dopants of strong electron-withdrawing systems, and dopants of hole transport materials, such as hexacyanohexaazatriphenylene, 2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinone dimethyl ether (F4TCNQ), 1,2,3-tris[(cyano)(4-cyano-2,3,5,6-tetrafluorophenyl)methylene]cyclopropane, etc.

[0088] In some embodiments, the material of the hole transport layer may be selected from, but is not limited to, aromatic amines with hole transport properties, as well as dimethylfluorene or carbazole materials and their derivatives.

[0089] In some embodiments, the material of the light-emitting layer can be a blue light-emitting material, such as, but not limited to, pyrene derivatives, anthracene derivatives, fluorene derivatives, perylene derivatives, amine derivatives, etc.

[0090] In some embodiments, the material of the electron transport layer is generally an aromatic heterocyclic compound, selected from, but not limited to, any one or a combination of two or more compounds and their derivatives of benzimidazole, triazine, pyrimidine, pyridine, pyrazine, quinoxaline, quinoline, diazole, diazaphosphazene, phosphine oxide, aromatic ketones, lactams, boranes, etc.

[0091] In some embodiments, the material of the electron injection layer is generally an alkali metal or a metal, such as LiF, Yb, Mg, Ca or their compounds.

[0092] In some embodiments, the anode is made of ITO glass and the cathode is made of Ag:Mg composite electrode.

[0093] In addition to the layers mentioned above, the organic electroluminescent device may also have other auxiliary functional layers as needed, such as a cover layer, an encapsulation layer, etc., but is not limited thereto.

[0094] Except for at least four organic layers, such as an electron blocking layer, a light-emitting layer, a hole blocking layer, and a light-emitting layer, which contain compounds with the structures shown in Formula 1 below, the specific structures, material compositions, and preparation methods of the cathode, anode, hole transport layer, electron transport layer, electron injection layer, hole injection layer, capping layer, and encapsulation layer in embodiments of this disclosure can adopt any suitable structure, material composition, and preparation method without particular limitation. This disclosure does not involve improvements to these components, and therefore these components are not described in detail to avoid obscuring the main technical concept of this disclosure.

[0095] Another embodiment of this disclosure provides a display device that includes an organic electroluminescent device according to this disclosure.

[0096] In some embodiments, the display device may include a plurality of organic electroluminescent devices, at least one of which is an organic electroluminescent device according to the present disclosure. For example, the organic electroluminescent device in the display device may be a blue, green, or red organic electroluminescent device, but is not limited thereto.

[0097] The display device described in this disclosure can be any product or component with a display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, digital photo frame, navigator, in-vehicle display, smartwatch, or smart bracelet. Other essential components of this display device are those that should be understood by those skilled in the art and will not be described in detail here, nor should they be construed as limiting this disclosure.

[0098] In this disclosure, the description method “each independent” should be interpreted broadly. It can mean that the specific options expressed by the same symbol in different groups do not affect each other, or that the specific options expressed by the same symbol in the same group do not affect each other.

[0099] In this disclosure, a non-positional substituent refers to a substituent connected by a single bond extending from the center of the ring system, which means that the substituent can be attached to any possible position in the ring system.

[0100] In this disclosure, unless otherwise specifically defined, "hybrid" means that a functional group includes at least one heteroatom selected from B, N, O, S, Se, Si, P, etc.

[0101] In this disclosure, "alkyl" can include straight-chain or branched alkyl groups. Unless otherwise specified, an alkyl group can have 1 to 10 carbon atoms, and in this disclosure, numerical ranges such as "1 to 10" refer to integers within a given range; for example, "1 to 10 carbon atoms" means an alkyl group that may contain 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. An alkyl group can also be a lower alkyl group having 1 to 6 carbon atoms. Furthermore, an alkyl group can be substituted or unsubstituted. An unsubstituted alkyl group can be a "saturated alkyl group" without any double or triple bonds. Optionally, the alkyl group is selected from alkyl groups having 1 to 6 carbon atoms, including but not limited to methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, pentyl, and hexyl.

[0102] In this disclosure, cycloalkyl refers to a group derived from a saturated cyclic carbon chain structure. Unless otherwise specified, cycloalkyl can have 3 to 10 carbon atoms, and in this disclosure, numerical ranges such as "3 to 10" refer to integers within a given range; for example, "3 to 10 carbon atoms" means a cycloalkyl group that may contain 3, 4, 5, 6, 7, 8, 9, or 10 carbon atoms. Cycloalkyl can be substituted or unsubstituted. Optionally, specific examples of cycloalkyl include, but are not limited to, cyclopentyl, cyclohexyl, etc.

[0103] In this disclosure, aryl refers to any optional functional group or substituent derived from an aromatic carbon ring. An aryl group can be a monocyclic aryl (e.g., phenyl) or a polycyclic aryl; in other words, an aryl group can be a monocyclic aryl, a fused-ring aryl, two or more monocyclic aryl groups conjugated by carbon-carbon bonds, a monocyclic aryl and a fused-ring aryl group conjugated by carbon-carbon bonds, or two or more fused-ring aryl groups conjugated by carbon-carbon bonds. That is, unless otherwise stated, two or more aromatic groups conjugated by carbon-carbon bonds can also be considered as aryl groups in this disclosure. Fused-ring aryl groups may include, for example, bicyclic fused aryl (e.g., naphthyl), tricyclic fused aryl (e.g., phenanthrene, fluorene, anthracene), etc. The aryl group does not contain heteroatoms such as B, N, O, S, P, Se, and Si. For example, in this disclosure, biphenyl, terphenyl, etc., are aryl groups. Examples of aryl groups may include, but are not limited to, phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, biphenyl, terphenyl, tetraphenyl, pentaphenyl, benzo[9,10]phenanthryl, pyrene, benzofluoranthracene, etc. The term "aryl" in this disclosure may contain 6-30 carbon atoms. In some instances, the number of carbon atoms in the aryl group may be 6-25; in others, it may be 6-18; and in still others, it may be 6-13. For example, in this disclosure, the number of carbon atoms in the aryl group may be 6, 10, 12, 13, 14, 15, 18, 20, 24, 25, or 30. Of course, other numbers of carbon atoms are also possible, which will not be listed here. In this disclosure, biphenyl can be understood as a phenyl-substituted aryl group or an unsubstituted aryl group.

[0104] In this disclosure, a heteroaryl group refers to a monovalent aromatic ring containing at least one, for example, 1, 2, 3, 4, or 5 heteroatoms, wherein the heteroatoms can be at least one selected from B, O, N, P, Si, Se, and S. The heteroaryl group can be a monocyclic heteroaryl or a polycyclic heteroaryl; in other words, a heteroaryl group can be a single aromatic ring system or a system of multiple aromatic rings connected by conjugation, and any aromatic ring system can be an aromatic monocyclic or an aromatic fused ring. For example, heteroaryl groups can include thiophene, furanyl, pyrrole, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridinel, pyridazinyl, pyrazinyl, quinolinyl, quinazolinyl, quinoxazinyl, phenoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, isoquinolinyl, indolyl, carbazole, benzoxazolyl, benzimidazolyl, benzo[] Thiazolyl, benzotriazolyl, benzocarbazole, benzothiophene, dibenzothiophene, thienobenzothiophene, benzofuranyl, phenanthrolinel, isoxazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, silanyl, dibenzofuranyl, and N-arylcarbazole (such as N-phenylcarbazole), N-heteroarylcarbazole (such as N-pyridylcarbazole), N-alkylcarbazole (such as N-methylcarbazole), etc., but not limited to these. Among them, thiophene, furanyl, phenanthroline, etc. are heteroaryl groups of the single aromatic ring type, while N-arylcarbazole and N-heteroarylcarbazole are heteroaryl groups of the polycyclic system type connected by conjugation. Unless otherwise specified, the "heteroaryl" in this application may contain 5-30 ring atoms. In some instances, the number of ring atoms in the heteroaryl may be 5-23, and in other instances, it may be 5-19. For example, the number of ring atoms may be 5, 6, 7, 10, 11, 12, 13, 18, 19, 20, 21, 22, 23, 25, or 30. Of course, the number of ring atoms may also be other numbers, which will not be listed here. In this disclosure, the substituted heteroaryl may be one or more hydrogen atoms of the heteroaryl being replaced by groups such as deuterium atoms, halogen groups, cyano groups, aryl groups, heteroaryl groups, alkyl groups, cycloalkyl groups, etc. Specific examples of aryl-substituted heteroaryl include, but are not limited to, phenyl-substituted dibenzofuranyl, phenyl-substituted dibenzothiophenyl, N-phenylcarbazoyl, etc. It should be understood that the number of carbon atoms in a substituted heteroaryl group refers to the total number of carbon atoms in the heteroaryl group and the substituents on it.

[0105] In this disclosure, the heterocyclic group is a monovalent non-aromatic ring containing at least one, for example, 1, 2, 3, 4, or 5 heteroatoms, which can be at least one selected from B, O, N, P, Si, Se, and S. The heterocyclic group can be monocyclic or polycyclic. For example, heterocyclic groups may include, but are not limited to, dihydropyridinyl, piperidinyl, tetrahydrothiopheneyl, sulfur-oxidized tetrahydrothiopheneyl, 4-piperidinoneyl, pyrrolyl, 2-pyrrolidoneyl, pyrrolinyl, tetrahydrofuranyl, bis-tetrahydrofuranyl, tetrahydropyranyl, bis-tetrahydropyranyl, tetrahydroquinolinyl, tetrahydroisoquinolinyl, decahydroquinolinyl, octahydroisoquinolinyl, azacyclic octacyclic tetracarbamatel, phenanthridine, acridine, pyrimidinyl, imidazoalkyl, imidazolinyl, pyrazolyl, piperazinyl, indololinyl, isoindololinyl, quininecycloyl, morpholinyl, oxazolyl, etc.

[0106] In this disclosure, the substituted or unsubstituted aromatic amino group refers to -NR'R", where R' and R" are each independently selected from the aforementioned aryl groups.

[0107] In this disclosure, the substituted or unsubstituted heteroarylamine group refers to -NR'R", where at least one of R' and R" is selected from the above-mentioned heteroaryl groups.

[0108] In this disclosure, the halogen group may include fluorine, iodine, bromine, chlorine, etc.

[0109] In this disclosure, the substituted silyl, boron, alkyl, cycloalkyl, heterocycloalkyl, aryl, heteroaryl, or heterocyclic groups may be groups in which one or more hydrogen atoms are replaced by groups such as deuterium, halogen groups, cyano, nitro, amino, hydroxyl, C6-C12 aryl, 5-12 heteroaryl, C1-C6 alkyl, C1-C6 alkoxy, C3-C6 cycloalkyl, etc.

[0110] In this disclosure, "C1-C40", "C6-C60", "C3-C60", etc., preceding a group refer to the number of carbon atoms contained in that group. For example, a C7 aryl group can be a tolyl group, which has 7 carbon atoms.

[0111] In this disclosure, "5-60 members" before the cyclic group refers to the number of ring atoms contained in the cyclic group. For example, a 5-membered ring refers to a ring with 5 ring atoms.

[0112] In this disclosure, the word “including” or variations thereof, such as “comprising,” “containing,” or “having,” will be understood to include the stated elements, integers, or steps, or combinations thereof, but does not preclude the addition of other elements, integers, or steps, or combinations thereof.

[0113] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. While those similar to or equivalent to the methods and materials described herein may be used in practice or testing of this disclosure, suitable methods and materials are described below. In case of conflict, this specification (including definitions) shall prevail. Furthermore, the materials, methods, and embodiments described are illustrative only and not intended to be limiting.

[0114] "At least one of A, B and C" has the same meaning as "at least one of A, B or C", both including the following combinations of A, B and C: only A, only B, only C, combinations of A and B, combinations of A and C, combinations of B and C, and combinations of A, B and C.

[0115] "A and / or B" includes the following three combinations: A only, B only, and a combination of A and B.

[0116] In this disclosure, unless otherwise stated, "multiple" means two or more.

[0117] Beneficial effects

[0118] This disclosure employs compounds of Formula 1 in multiple organic layers. This simplifies the synthesis process of organic compounds, reduces synthesis costs, and ensures that at least three of the at least four organic layers are adjacent. Since these deuterated naphthyl compounds share the same principal structure, this significantly reduces the HOMO-LUMO energy level difference for hole or electron transport between the at least three organic layers, thereby reducing interface effects and facilitating electron and / or hole injection. Furthermore, the presence of deuterium atoms in the structure enhances molecular stability, thereby improving device lifetime, luminous efficiency, and reducing voltage. The deuterium-containing CPL material structure also increases molecular stability, preventing capping failure and device efficiency reduction caused by degradation due to metal ion diffusion from adjacent inorganic layers of the CPL. Detailed Implementation

[0119] To objectively evaluate the technical effects of the embodiments of this disclosure, the technical solutions provided by this disclosure will be described in detail and by way of examples below. These embodiments are provided to make this disclosure more comprehensive and complete, and to fully convey the concept of exemplary embodiments to those skilled in the art. The features, structures, or characteristics described in these exemplary embodiments can be combined in any suitable manner in one or more embodiments, thereby enabling implementation in various forms, and therefore should not be construed as limited to the examples set forth herein. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments provided by this disclosure are within the scope of protection of this disclosure.

[0120] Example

[0121] The following provides the synthesis process of compounds containing benzo[a]heterocyclic structures according to some exemplary embodiments of this disclosure, as well as the results of testing and comparison of the performance of the prepared electroluminescent devices.

[0122] Synthesis Example 1: Synthesis of Compound A11

[0123]

[0124] Under visible light irradiation, 0.11 mol of intermediate 1 and 0.1 mol of compound Z were reacted in 500 ml of a Ba(OH)₂ / 95% EtOH solvent mixture in the presence of 0.1 g tetrakis(triphenylphosphine)palladium (80 °C). A 100 W tungsten filament bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 2.

[0125]

[0126] Under visible light irradiation, 0.11 mol of intermediate 2 and 0.1 mol of intermediate 3 were added to a 500 mL mixture of Ba(OH)₂ / 95% EtOH solvent in the presence of 0.1 g tetrakis(triphenylphosphine)palladium and reacted (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, yielding compound A11.

[0127] Mass spectrometry m / z: 548.68, elemental content (%): C 42 H 24D2O, C, 91.94; H, 5.14; O, 2.92.

[0128] 1 H NMR (500MHz, CDCl3): δ8.5(H),8.21(4H),8.4214(H),7.98(H),7.82(H),7.76-7.77(2H),7.54(H),7.37-7.39(5H),7.31(H),7.25(4H).

[0129] Synthesis Example 2: Synthesis of Compound B11

[0130]

[0131] The reaction was synthesized in a one-pot manner using 0.05 mol t-BuONa as a base, 0.1 mol di-tert-butyl benzoate as a ligand, and 0.1 g Pd(dba)₂ as a catalyst. 500 mL of toluene was used as the solvent. 0.1 mol of compound Z and 0.1 mol of intermediate 6 were added. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. The mixture was allowed to stand at room temperature for recrystallization. The resulting solid was filtered and washed with ethanol to obtain intermediate 8.

[0132]

[0133] The reaction was synthesized in a one-pot manner using 0.05 mol t-BuONa as a base, 0.1 mol di-tert-butyl benzoate as a ligand, 0.1 g Pd(dba)2 as a catalyst, and toluene as a solvent. 0.1 mol intermediate 8 and 0.1 mol intermediate 9 were added. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. The mixture was allowed to stand at room temperature for recrystallization. The resulting solid was filtered and washed with ethanol to obtain compound B11.

[0134] Mass spectrometry m / z: 639.25, elemental content (%): C 48 H 29 D2NO, C, 90.11; H, 5.20; N, 2.19; O, 2.50.

[0135] 1 H NMR (500MHz, CDCl3): δ8.88(H),8.7(H),8.5(H),8.14(H),8.02-8.09(4H),7.9-7.98(4H ),7.75-7.77(2H),7.63-7.68(3H),7.51-7.55(6H),7.54(H),7.37-7.39(5H),7.31(H);

[0136] Synthesis Example 3: Synthesis of Compound C11

[0137]

[0138] Under visible light irradiation, 0.11 mol of intermediate 10 and 0.1 mol of intermediate 11 were added to a 500 ml mixture of Ba(OH)₂ / 95% EtOH solvent in the presence of 0.1 g tetrakis(triphenylphosphine)palladium and reacted (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was completed, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 12.

[0139]

[0140] Under visible light irradiation, 0.1 mol of intermediate 13 and 0.1 mol of compound Z were reacted in 500 ml of a Ba(OH)2 / 95% EtOH solvent mixture in the presence of 0.1 g tetrakis(triphenylphosphine)palladium (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 14.

[0141]

[0142] Under visible light irradiation, 0.1 mol of intermediate 12 and 0.1 mol of intermediate 14 were reacted in 500 ml of a Ba(OH)2 / 95% EtOH solvent mixture in the presence of 0.1 g of tetrakis(triphenylphosphine)palladium (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 15.

[0143]

[0144] Under visible light irradiation, 0.1 mol of intermediate 15 and 0.1 mol of intermediate 16 were reacted in 500 ml of a Ba(OH)₂ / 95% EtOH solvent mixture in the presence of 0.1 g of tetrakis(triphenylphosphine)palladium (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, yielding compound C11.

[0145] Mass spectrometry m / z: 753.31, elemental content (%): C 56 H 35 D2N3, C, 89.21; H, 5.21; N, 5.57.

[0146] 1 H NMR (500MHz, CDCl3): δ8.5(H),8.14(H),8.07-8.09(3H),7.96(4H),7.89-7.9(2H),7.7 5-7.78(4H),7.55(H),7.49(2H),7.38-7.41(2H),7.25-7.28(9H),7.18(2H),7.1(4H);

[0147] Synthesis Example 4: Synthesis of Compound D11

[0148]

[0149] Using 0.02 g t-BuONa as a base, 0.02 g di-tert-butyl benzoate as a ligand, and 0.05 g Pd(dba)₂ as a catalyst, and 500 mL toluene as a solvent, 0.1 mol of intermediate 17 and 0.1 mol of compound Z were added for a one-pot synthesis. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 18.

[0150]

[0151] The reaction was synthesized in a one-pot process using 0.02 g t-BuONa as a base, 0.02 g di-tert-butyl benzoate as a ligand, and 0.05 g Pd(dba)₂ as a catalyst, with 500 mL toluene as the solvent. Intermediates 18 (0.1 mol) and 19 (0.1 mol) were added. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. The mixture was allowed to stand at room temperature for recrystallization. The resulting solid was filtered and washed with ethanol to obtain compound D11.

[0152] Mass spectrometry m / z: 651.17, elemental content (%): C 44 H 25 D2NOS2, C, 81.08; H, 4.48; N, 2.15; O, 2.45; S, 9.84.

[0153] 1 H NMR (500MHz, CDCl3): δ8.5(H),8.28(H),8.11(H),8.07-8.09(2H),8.03(H),7.75-7.8( 3H),7.69(H),7.55(2H),7.42-7.49(2H),7.37(4H),7.31(H),6.99-7.12(4H),6.91(H);

[0154] Synthesis Example 5: Synthesis of Compound C12

[0155]

[0156] Under visible light irradiation, 0.1 mol of intermediate 20 and 0.1 mol of compound 14 were reacted in 500 ml of a Ba(OH)2 / 95% EtOH solvent mixture in the presence of 0.1 g tetrakis(triphenylphosphine)palladium (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. The mixture was allowed to stand at room temperature for recrystallization. The resulting solid was filtered and washed with ethanol to obtain intermediate 21.

[0157]

[0158] Under visible light irradiation, 0.1 mol of intermediate 21 and 0.1 mol of intermediate 22 were reacted in 500 ml of a Ba(OH)2 / 95% EtOH solvent mixture in the presence of 0.1 g of tetrakis(triphenylphosphine)palladium (135 °C). A 100 W tungsten filtrate bulb was used as the irradiation source, and the reaction flask was immersed in a water bath to prevent photothermal effects. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, which yielded intermediate 23.

[0159]

[0160] Mass spectrometry m / z: 805.34, elemental content (%): C 60 H 35 D4N3, C, 89.41; H, 5.38; N, 5.21.

[0161] 1 H NMR (500MHz, CDCl3): δ8.5(2H), 8.14(2H), 8.07-8.09(5H), 7.96(4H), 7.89-7. 9(2H),7.77-7.78(3H),7.55(H),7.38(H),7.25-7.28(9H),7.18(2H),7.1(4H);

[0162] Synthesis Example 6: Synthesis of Compound D13

[0163]

[0164] Using 0.02 g t-BuONa as a base, 0.02 g di-tert-butyl benzoate as a ligand, and 0.05 g Pd(dba)₂ as a catalyst, and 500 mL toluene as a solvent, 0.1 mol of intermediate 25 and 0.1 mol of compound Z were added in a one-pot reaction. After the reaction was complete, the mixture was cooled to room temperature and filtered through diatomaceous earth to obtain the filtrate. The filtrate was concentrated, heated, and a small amount of ethanol was added. After standing at room temperature for recrystallization, the mixture was filtered and washed with ethanol to obtain the recrystallized solid, yielding compound D13.

[0165] Mass spectrometry m / z: 657.87, elemental content (%): C 48 H 27 D4NS, C, 87.64; H, 5.36; N, 2.13; S, 4.87.

[0166] 1 H NMR (500MHz, CDCl3): δ8.5(2H),8.28(H),8.14(2H),8.11(H),8.07-8.09(4H),8. 01(H),7.86(H),7.75-7.78(4H),7.64-7.69(2H),7.55(4H),7.43(H),7.37(4H);

[0167] Device Examples:

[0168] The structure of some of the materials used is shown in the table below.

[0169]

[0170]

[0171]

[0172] Top-emitting devices were prepared by vacuum evaporation, and the effectiveness of the organic electroluminescent device of the present invention was tested.

[0173] The device structure is as follows: anode / hole injection layer (HIL) / hole transport layer (HTL) / electron blocking layer (EBL) / light emitting layer (EL) / hole blocking layer (HBL) / electron transport layer (ETL) / electron injection layer (EIL) / cathode / light emitting layer (CPL).

[0174] The fabrication process of OLED devices includes: cleaning and drying a pre-prepared ITO substrate; sequentially depositing HIL, HTL, and EBL materials on the anode; then depositing the light-emitting layer material; depositing HBL, ETL, and EIL materials on the light-emitting layer; then depositing the cathode; and finally depositing a CPL layer on top of the cathode. The device is encapsulated in glass UV packaging.

[0175] Comparative Example 1

[0176] ITO / m-MTDATA:F4TCNQ(3%, 10nm) / m-MTDATA(110nm) / CBP(5nm) / BH1:BD(5%, 20nm) ) / TPBI(5nm) / BCP:Liq(1:1,30nm) / Yb(1nm) / Mg:Ag(13nm) / CP1(50nm) / CP1(50nm)

[0177] In the above structure,

[0178] ITO is used as the anode, with a thickness of 70nm;

[0179] The host material of the hole injection layer (HIL) is m-MTDATA, the guest material is F4TCNQ, the doping concentration of the guest material is 5% by weight, and the thickness is 110 nm.

[0180] The hole transport layer (HTL) is made of m-MTDATA and has a thickness of 110 nm.

[0181] The electron blocking layer (EBL) is made of CBP and has a thickness of 5 nm.

[0182] The host material of the light-emitting layer is BH1, the guest material is BD, the doping concentration of the guest material is 5% by weight, and the thickness is 20 nm.

[0183] The hole blocking layer (HBL) is made of TPBI and has a thickness of 5 nm.

[0184] The host material of the electron transport layer (ETL) is BCP, the guest material is Liq, the doping ratio of the host material to the guest material is 1:1, and the thickness is 30nm.

[0185] The electron injection layer (EIL) is made of Yb and has a thickness of 1 nm.

[0186] The cathode is made of a Mg / Ag alloy and has a thickness of 13 nm.

[0187] The light-emitting layer (CPL) consists of two layers, each made of CP1 material with a thickness of 50 nm.

[0188] Example 1

[0189] ITO / m-MTDATA:F4TCNQ(3%, 10nm) / m-MTDATA(110nm) / B11(5nm) / A11:BD(5%, 20nm) / C11(5nm) / BCP:Liq(1:1,30nm) / Yb 1nm / Mg:Ag 13nm / CP1 50nm / D11 50nm

[0190] In the above structure,

[0191] ITO is used as the anode, with a thickness of 70nm;

[0192] The host material of the hole injection layer (HIL) is m-MTDATA, the guest material is F4TCNQ, the doping concentration of the guest material is 5% by weight, and the thickness is 110 nm.

[0193] The hole transport layer (HTL) is made of m-MTDATA and has a thickness of 110 nm.

[0194] The electron blocking layer (EBL) is made of B11 and has a thickness of 5 nm.

[0195] The host material of the light-emitting layer is Al11, the guest material is BD, the doping concentration of the guest material is 5% by weight, and the thickness is 20 nm.

[0196] The hole blocking layer (HBL) is made of C11 and has a thickness of 5 nm.

[0197] The host material of the electron transport layer (ETL) is BCP, the guest material is Liq, the doping ratio of the host material to the guest material is 1:1, and the thickness is 30nm.

[0198] The electron injection layer (EIL) is made of Yb and has a thickness of 1 nm.

[0199] The cathode is made of a Mg / Ag alloy and has a thickness of 13 nm.

[0200] The light-emitting layer (CPL) consists of two layers: the first layer is made of CP1 and has a thickness of 50 nm; the second layer is made of D11 and has a thickness of 50 nm.

[0201] Example 2

[0202] ITO / m-MTDATA:F4TCNQ(3%, 10nm) / m-MTDATA(110nm) / B11(5nm) / A11:BD(5%, 20nm) / C12(5nm) / BCP:Liq(1:1,30nm) / Yb 1nm / Mg:Ag 13nm / CP1 50nm / D13 50nm

[0203] Except that the hole blocking layer (HBL) is made of C12 and the second layer of the light-emitting layer (CPL) is made of D13, everything else is the same as in Example 1.

[0204] The performance of the blue organic electroluminescent device prepared above is analyzed as follows:

[0205] External quantum efficiency is measured using an external quantum efficiency meter.

[0206] Voltage was measured using an IVL tester.

[0207] Lifespan was tested using an M6000 OLED lifespan tester.

[0208] The experimental results are shown in Table 1.

[0209] Table 1 shows the data of the prepared blue organic electroluminescent devices.

[0210]

[0211] As shown in Table 1, compared with the device of Comparative Example 1 which does not conform to the present disclosure, the devices of Examples 1 and 2 prepared using the structure required by the present disclosure have higher light extraction efficiency, improved stability, and improved efficiency and lifespan.

[0212] While this disclosure has been described above, the content is merely an embodiment for the purpose of understanding this disclosure and is not intended to limit this disclosure. Any person skilled in the art may make any modifications and changes in the form and details of the implementation without departing from the spirit and scope disclosed herein, but the scope of patent protection of this disclosure shall still be determined by the scope defined in the appended claims.

Claims

1. An organic electroluminescent device comprising at least four organic layers, wherein at least three of the four organic layers are adjacent organic layers between a cathode and an anode, and each comprises a compound having the structure shown in Formula 1: （1） in, One of X1 to X8 is a site attached to the main structure of the compound, and the other seven are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1-C40 alkyl, substituted or unsubstituted C6-C60 arylamine, substituted or unsubstituted 5-60 heteroarylamine, substituted or unsubstituted 3-60 heteroaryl, substituted or unsubstituted C3-C60 aryl, and at least one contains a deuterium atom. The adjacent organic layers are a light-emitting layer, an electron-blocking layer, and a hole-blocking layer. The main material contained in the light-emitting layer has the following structure: （A） R1 and R2 are each independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer from 0 to 7; n is an integer from 0 to 8; L1 and L2 are each independently directly bonded, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, and carbazolylene; The electron blocking layer contains materials with the following structure: （B） R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group; R2 is selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer between 0 and 7; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranyl, dibenzothiopheneyl, or carbazoyl. The hole-blocking layer contains materials with the following structure: （C） R1 and R2 are each independently selected from substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups, or substituted or unsubstituted heterocyclic groups; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolyl.

2. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation 1 is the same as the structure shown in Equation 1-1 or 1-2: （1-1） X2 to X8 are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1 to C40 alkyl, substituted or unsubstituted C6 to C60 aromatic amino, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted C3 to C60 aryl, and at least one contains a deuterium atom; （1-2） X1 to X7 are each independently selected from hydrogen, deuterium, halogen, nitro, cyano, substituted or unsubstituted C1 to C40 alkyl, substituted or unsubstituted C6 to C60 aromatic amino, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted 5 to 60 heteroaryl, substituted or unsubstituted C3 to C60 aryl, and at least one contains a deuterium atom.

3. The organic electroluminescent device according to claim 2, wherein, In the structure shown in Formula 1-1, X2, X5, X7, and X8 are each independently selected from hydrogen and deuterium, X3 and X4 are deuterium, and X6 is selected from hydrogen, deuterium, and phenyl. In the structure shown in Formula 1-2, X1, X2, X5, and X7 are each independently selected from hydrogen and deuterium, X3 and X4 are deuterium, and X6 is selected from hydrogen, deuterium, and phenyl.

4. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation 1 is selected from the following structures: 。 5. The organic electroluminescent device according to any one of claims 1-4, wherein, The at least four organic layers are a light-emitting layer, an electron-blocking layer, a hole-blocking layer, and a light-emitting layer, wherein the light-emitting layer, the electron-blocking layer, and the hole-blocking layer are adjacent to each other; the light-emitting layer is disposed on the side of the cathode away from the anode.

6. The organic electroluminescent device according to claim 1, wherein, In the structure shown in Equation A, R2 is selected from deuterium and phenyl, Y is O or S, m is 0 or 1, n is 0, and L1 and L2 are each independently directly bonded, phenylene or biphenylene.

7. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation A is selected from the following structures: R1 and R2 are each independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer from 0 to 7; n is an integer from 0 to 8; L1 and L2 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazoylene. Formula 1 is selected from Formula 1 as described in any one of claims 1-4.

8. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation A is selected from the following structures: 。 9. The organic electroluminescent device according to claim 1, wherein, In the structure shown in equation B, R1 is selected from the structure shown in Formula 1 of any one of claims 1-4, phenanthrene, biphenyl, Y is O or S, m is 0 or 1, R2 is selected from deuterium and phenyl, L1 and L2 are each independently directly bonded or phenylene, and L3 is phenylene.

10. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation B is selected from the following structures: （B-1） R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group; R2 is selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer between 0 and 7; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolylene; Formula 1 is selected from Formula 1 as described in any one of claims 1-4.

11. The organic electroluminescent device according to claim 1, wherein, The structure shown in Equation B is selected from the following structures: 。 12. The organic electroluminescent device according to claim 1, wherein, In the structure shown in equation C, R1 is ; R2 is selected from the structure shown in Formula 1 of any one of claims 1-4, biphenyl, phenyl, phenanthrene, L1 is a phenylene; L2 and L3 are each independently a direct bond or a phenylene.

13. The organic electroluminescent device according to claim 1, wherein, The structure shown in equation C is selected from the following structures: （C-1） R1 and R2 are each independently selected from substituted or unsubstituted aryl groups, substituted or unsubstituted heteroaryl groups, or substituted or unsubstituted heterocyclic groups; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranyl, dibenzothiopheneyl, or carbazoyl. Formula 1 is selected from Formula 1 as described in any one of claims 1-4.

14. The organic electroluminescent device according to claim 1, wherein, The structure shown in equation C is selected from the following structures: 。 15. The organic electroluminescent device according to claim 5, wherein, The light-emitting layer contains materials with the following structure: （D） R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group; R2 is independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer between 0 and 7; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolyl; A semi-circular shape indicates that the aromatic or non-aromatic rings are fused or unfused at that location; Formula 1 is selected from Formula 1 as described in any one of claims 1-4.

16. The organic electroluminescent device according to claim 15, wherein, In the structure shown in equation D, R1 is a benzo-substituted or unsubstituted heteroaryl group; Y is O or S; m is 0; L1 is phenylene; L2 and L3 are each independently directly bonded or phenylene.

17. The organic electroluminescent device according to claim 15, wherein, The structure shown in equation D is selected from the following structures: （D-1） R1 is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic group; R2 is independently selected from deuterium, halogen, cyano, nitro, hydroxyl, substituted or unsubstituted silyl, substituted or unsubstituted boron, substituted or unsubstituted alkyl, substituted or unsubstituted cycloalkyl, substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or substituted or unsubstituted heterocyclic. Y is either O or S; m is an integer between 0 and 7; L1 to L3 are each independently a direct bond, phenylene, biphenylene, naphthylene, phenanthrene, dibenzofuranylene, dibenzothiopheneylene, or carbazolyl; A semi-circular shape indicates that the aromatic or non-aromatic rings are fused or unfused at that location; Formula 1 is selected from Formula 1 as described in any one of claims 1-4.

18. The organic electroluminescent device according to claim 15, wherein, The structure shown in equation D is selected from the following structures: 。 19. The organic electroluminescent device according to claim 5, comprising an anode, a hole injection layer, a hole transport layer, an electron blocking layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, a cathode, and a light-emitting layer.

20. A display device comprising an organic electroluminescent device according to any one of claims 1-19.

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