CN119546051A

CN119546051A - Light-emitting device, method for preparing light-emitting device, and electronic device

Info

Publication number: CN119546051A
Application number: CN202311123242.5A
Authority: CN
Inventors: 吴劲衡
Original assignee: TCL Technology Group Co Ltd
Current assignee: TCL Technology Group Co Ltd
Priority date: 2023-08-31
Filing date: 2023-08-31
Publication date: 2025-02-28

Abstract

The application discloses a light-emitting device, a preparation method of the light-emitting device and electronic equipment, wherein the light-emitting device comprises an anode, a cathode, a light-emitting layer, an electronic functional layer and an auxiliary layer, the anode and the cathode are oppositely arranged, the light-emitting layer is arranged between the anode and the cathode, the electronic functional layer is arranged between the cathode and the light-emitting layer, the auxiliary layer comprises a connecting group, the connecting group comprises two sulfur atoms and at least one carbon-carbon double bond, the connecting group is connected with the electronic functional layer through one sulfur atom, and the connecting group is connected with the light-emitting layer through another sulfur atom, so that the light-emitting efficiency and the service life of the light-emitting device are improved.

Description

Light emitting device, manufacturing method of light emitting device and electronic equipment

Technical Field

The application relates to the technical field of photoelectricity, in particular to a light-emitting device, a preparation method of the light-emitting device and electronic equipment.

Background

The Light Emitting device refers to a type of device that emits Light by injection and recombination of carriers, and includes, but is not limited to, organic Light-Emitting Diodes (OLED) and Quantum Dot LIGHT EMITTING Diodes (QLED). The light-emitting device has a sandwich structure, namely comprises an anode, a cathode and a light-emitting layer, wherein the anode and the cathode are arranged oppositely, and the light-emitting layer is arranged between the anode and the cathode. The light emitting device has the light emitting principle that electrons are injected from the cathode of the device to the light emitting area, holes are injected from the anode of the device to the light emitting area, the electrons and the holes are combined in the light emitting area to form excitons, and photons are released by the combined excitons in a radiation transition mode, so that light is emitted.

The light emitting device has been developed for many years, and the performance index of the light emitting device has been greatly improved, and the light emitting device also has great application development potential, but the current disadvantages still exist, such as the service life of the light emitting device is still further improved. Therefore, how to further increase the device lifetime of the light emitting device has important significance for the application and development of the light emitting device.

Disclosure of Invention

The application provides a light emitting device, a preparation method of the light emitting device and electronic equipment, so as to improve the service life of the light emitting device.

In a first aspect, the present application provides a light emitting device comprising:

An anode and a cathode disposed opposite each other;

a light-emitting layer disposed between the anode and the cathode;

an electron functional layer disposed between the cathode and the light emitting layer, and

An auxiliary layer disposed between the electronic functional layer and the light emitting layer;

Wherein the auxiliary layer comprises a connecting group, and the connecting group is a first group with a structure shown in the following general formula (I) and/or a second group with a structure shown in the following general formula (II):

Wherein, the connection group is respectively connected with the electronic functional layer and the luminescent layer;

R ₁、R₂、R₅ and R ₆ are independently selected from one or more of hydrogen, deuterium, tritium, substituted or unsubstituted C1-C10 straight-chain or branched-chain hydrocarbon groups, substituted or unsubstituted aliphatic cyclic hydrocarbon groups with 3-30 ring atoms, substituted or unsubstituted aliphatic heterocyclic hydrocarbon groups with 3-30 ring atoms, substituted or unsubstituted aryl groups with 6-30 ring atoms, and substituted or unsubstituted heteroaryl groups with 5-30 ring atoms;

R ₃、R₄、R₇ and R ₈ are independently selected from- (CH ₂)_n -or-CH=CH-, and n is a positive integer of 1-6.

Optionally, the substituted or unsubstituted C1-C10 straight or branched hydrocarbon group is selected from C1-C3 straight or branched hydrocarbon groups, and/or

The substituted or unsubstituted C1-C10 linear hydrocarbyloxy or branched hydrocarbyloxy is selected from C1-C3 linear hydrocarbyloxy or branched hydrocarbyloxy, and/or

The substituted or unsubstituted aliphatic cyclic hydrocarbon group having 3 to 30 ring atoms is selected from the group consisting of aliphatic cyclic hydrocarbon groups having 3 to 10 ring atoms, and/or

The substituted or unsubstituted aliphatic heterocyclic hydrocarbon group with 3-30 ring atoms is selected from aliphatic heterocyclic hydrocarbon groups with 3-10 ring atoms, and/or

The substituted or unsubstituted aryl group having 6 to 30 ring atoms is selected from aryl groups having 6 to 18 ring atoms, and/or

The substituted or unsubstituted heteroaryl group with the number of ring atoms of 5-30 is selected from heteroaryl groups with the number of ring atoms of 5-18.

Optionally, the linking group is selected from one or more of the following groups:

Optionally, the material of the electronic functional layer comprises a first inorganic compound, the connecting group is connected with the first inorganic compound, and the first inorganic compound comprises one or more of undoped first metal oxide, doped second metal oxide, II-VI semiconductor material, III-V semiconductor material and I-III-VI semiconductor material;

Wherein the undoped first metal oxide is selected from one or more of ZnO, tiO ₂、SnO₂、BaO、Ta₂O₃、Al₂O₃ and ZrO ₂, and/or the doped second metal oxide is a host metal oxide doped with a first doping element selected from one or more of ZnO, tiO ₂、SnO₂、BaO、Ta₂O₃、Al₂O₃ or ZrO ₂, the first doping element is selected from one or more of Mg, ca, zr, W, ga, li, al, ti, Y, in and Sn, and/or the mole percentage of the first doping element in the doped second metal oxide is below 50%, and/or the II-VI semiconductor material is selected from one or more of ZnS, znSe and CdS, and/or the III-V semiconductor material is selected from one or more of InP and GaP, and/or the I-III-VI semiconductor material is selected from one or more of CuInS and CuGaS, and/or

The material of the light-emitting layer comprises quantum dots, and the connecting group is connected with the quantum dots; the quantum dots are selected from one or more of single component quantum dots, core-shell structure quantum dots, inorganic perovskite quantum dots, organic perovskite quantum dots and organic-inorganic hybrid perovskite quantum dots; the material of the single component quantum dot, the material of the core-shell structure quantum dot and the material of the shell of the core-shell structure quantum dot are selected from at least one of II-VI compound, III-V compound, IV-VI compound or I-III-VI compound independently of each other, wherein the II-VI compound is selected from one or more of CdS、CdSe、CdTe、ZnS、ZnSe、ZnTe、ZnO、HgS、HgSe、HgTe、CdSeS、CdSeTe、CdSTe、ZnSeS、ZnSeTe、ZnSTe、HgSeS、HgSeTe、HgSTe、CdZnS、CdZnSe、CdZnTe、CdHgS、CdHgSe、CdHgTe、HgZnS、HgZnSe、HgZnTe、CdZnSeS、CdZnSeTe、CdZnSTe、CdHgSeS、CdHgSeTe、CdHgSTe、HgZnSeS、HgZnSeTe and HgZnSTe, the III-V compound is selected from one or more of GaN、GaP、GaAs、GaSb、AlN、AlP、AlAs、AlSb、InN、InP、InAs、InSb、GaNP、GaNAs、GaNSb、GaPAs、GaPSb、AlNP、AlNAs、AlNSb、AlPAs、AlPSb、InNP、InNAs、InNSb、InPAs、InPSb、GaAlNP、GaAlNAs、GaAlNSb、GaAlPAs、GaAlPSb、GaInNP、GaInNAs、GaInNSb、GaInPAs、GaInPSb、InAlNP、InAlNAs、InAlNSb、InAlPAs and InAlPSb, the IV-VI compound is selected from one or more of SnS、SnSe、SnTe、PbS、PbSe、PbTe、SnSeS、SnSeTe、SnSTe、PbSeS、PbSeTe、PbSTe、SnPbS、SnPbSe、SnPbTe、SnPbSSe、SnPbSeTe and SnPbSTe, the I-III-VI compound is selected from one or more of CuInS, cuInSe and AgInS, and/or the inorganic perovskite quantum dot has a structural formula of AMX ₃, wherein A is Cs ⁺, M is a divalent metal cation, M is selected from one or more of Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺ and ²⁺, X is a halogen anion and/or a perovskite of the general formula of CMM-III-VI compound is selected from one or more of CuInS, and/or a perovskite of the general formula of CMM-III-VI compound is selected from one or more of C-III-VI compound and AgInS, and/or the organic perovskite quantum dot has a general formula of BMB and/or a quantum dot of the general formula of BMB is selected from the group consisting of organic and/or the organic amine quantum dot having a general formula of CMB and/C is 34B.

Optionally, the material of the anode and the material of the cathode independently of each other comprise one or more of a metal, a carbon material and a third metal oxide, wherein the metal is selected from one or more of Al, ag, cu, mo, au, ba, pt, ca, ir, ni and Mg, and/or the carbon material is selected from one or more of graphite, carbon nanotubes, graphene and carbon fibers, and/or the third metal oxide is selected from one or more of indium doped tin oxide, fluorine doped tin oxide, antimony doped tin oxide, aluminum doped zinc oxide, gallium doped zinc oxide, indium doped zinc oxide, magnesium doped zinc oxide, aluminum doped magnesium oxide, snO ₂, znO and In ₂O₃, and/or

The light emitting device further comprises a hole functional layer, wherein the hole functional layer is arranged between the anode and the light emitting layer, and the material of the hole functional layer comprises undoped second inorganic compound, doped third inorganic compound, poly (3, 4-ethylenedioxythiophene), poly (styrenesulfonic acid), copper phthalocyanine, titanyl phthalocyanine, 2,3,5, 6-tetrafluoro-7, 7', 8' -tetracyanodimethyl-p-benzoquinone, 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazabenzophenanthrene, polypyrrole, polyaniline, 3-hexyl substituted polythiophene, poly (9-vinylcarbazole), 4 '-di (9-carbazole) biphenyl, poly [ bis (4-phenyl) (4-butylphenyl) amine ], 4' -cyclohexyldi [ N, N-di (4-methylphenyl) aniline ], poly [ (9, 9-dioctylfluorenyl-2, 7-diyl) -co- (4, 4'- (4, 4-diphenyl)' - (N, 4', 4-di (4, 4' -N-methylphenyl) aniline, 3,4 '-sec-butylphenyl) amine, and (4, 4' -di (4-methylphenyl) aniline. One or more of 4' -tris (2-naphthylphenylamino) triphenylamine, N ' -diphenyl-N, N ' - (1-naphthyl) -1,1' -biphenyl-4, 4' -diamine, N ' -diphenyl-N, N ' -bis (3-methylphenyl) -1,1' -biphenyl-4, 4' -diamine, N ' -bis [4- (diphenylamino) phenyl ] -N, N ' -diphenyl benzidine, N ' -bis (3-methylphenyl) -N, N ' -diphenyl-9, 9-spirobifluorene-2, 7-diamine, N2, N7-bis-1-naphthyl-N2, N7-diphenyl-9, 9' -spirobifluorene ] -2, 7-diamine, poly [ bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine ] and2, 2', 7' -tetrakis [ N, N-bis (4-methoxyphenyl) amino ] -9,9' -spirobifluorene; wherein the undoped second inorganic compound is selected from one or more of graphene, C60, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, P-type gallium nitride, chromium oxide, copper sulfide, molybdenum sulfide and tungsten sulfide, and/or the doped third inorganic compound is a main inorganic compound doped with a second doping element, and the main inorganic compound is selected from graphene, C60, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, one or more of P-type gallium nitride, chromium oxide, copper sulfide, molybdenum sulfide, and tungsten sulfide, and/or one or more of nickel, molybdenum, tungsten, vanadium, chromium, copper, and a platinum group metal element.

In a second aspect, the present application provides a method for manufacturing a light emitting device, comprising the steps of:

providing a bottom electrode, forming a light emitting layer on one side of the bottom electrode, and

Forming a top electrode on one surface of the light-emitting layer away from the bottom electrode;

Wherein when the light emitting device is of a positive structure, the bottom electrode is an anode and the top electrode is a cathode, after the step of forming the light emitting layer and before the step of forming the top electrode, the method further comprises the steps of depositing a solution containing an auxiliary functional material on a side of the light emitting layer away from the bottom electrode to connect at least a portion of the auxiliary functional material with the light emitting layer, and then forming an electronic functional layer on a side of the light emitting layer where the solution is deposited, with an auxiliary layer formed between the electronic functional layer and the light emitting layer, or

When the light emitting device is of an inverted structure, the bottom electrode is a cathode and the top electrode is an anode, and before the step of forming a light emitting layer on one side of the bottom electrode, the preparation method further comprises the steps of forming an electronic functional layer on one side of the bottom electrode, and then depositing a solution containing an auxiliary functional material on the side of the electronic functional layer away from the bottom electrode so as to connect at least part of the auxiliary functional material with the electronic functional layer;

Wherein the auxiliary functional material comprises a compound with a structure shown in the following general formula (III) and/or a compound with a structure shown in the following general formula (IV):

Optionally, the mass of the auxiliary functional material accounts for 3% -5% of the total mass of the solution, and/or

The deposition thickness of the solution is 5 nm-10 nm, and/or

The substituted or unsubstituted C1-C10 linear or branched hydrocarbon group is selected from C1-C3 linear or branched hydrocarbon group, and/or

Optionally, the auxiliary functional material is selected from one or more of the following compounds:

optionally, when the light emitting device is in a front structure, the preparation method further comprises the step of removing the auxiliary functional material not connected to the light emitting layer after the step of depositing a solution containing the auxiliary functional material on a side of the light emitting layer away from the bottom electrode and before the step of forming the electronic functional layer;

Or when the light emitting device is of an inverted structure, the preparation method further comprises the step of removing the auxiliary functional material which is not connected with the electronic functional layer after the step of depositing a solution containing the auxiliary functional material on the side of the electronic functional layer away from the bottom electrode and before the step of forming the light emitting layer.

In a third aspect, the present application also provides an electronic device comprising a light-emitting device according to any one of the first aspects or a light-emitting device manufactured by a manufacturing method according to any one of the second aspects.

The application provides a light-emitting device, a preparation method of the light-emitting device and electronic equipment, which have the following technical effects:

in the light emitting device, through setting up the auxiliary layer between electron functional layer and luminescent layer, the auxiliary layer includes connecting group, and connecting group is connected with electron functional layer and luminescent layer respectively, can promote the connection compactness between luminescent layer and the electron functional layer, has reduced the risk of electron functional layer and luminescent layer separation to the device life-span of light emitting device has effectively been promoted.

Drawings

The technical solution and other advantageous effects of the present application will be made apparent by the following detailed description of the specific embodiments of the present application with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a light emitting device according to an embodiment of the present application.

The reference numerals are as follows:

10, 11, 12, 13, 14, 15, 16, 161, 162 and 162 parts of light emitting device, anode, cathode, auxiliary layer, electron functional layer, hole injection layer, hole transport layer.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. It will be apparent that the described embodiments are only some, but not all, embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to fall within the scope of the application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In addition, any methods and materials similar or equivalent to those described herein can be used in the present application. The preferred methods and materials described herein are illustrative only and should not be construed as limiting the application.

It should be noted that the following description of the embodiments is not intended to limit the preferred order of the embodiments, and it should be understood that the various embodiments of the application may exist in a range format, and that the description of the range format is merely for convenience and brevity and should not be construed as a limitation on the scope of the application, thus, it should be construed that the range format specifically discloses all possible sub-ranges and individual numerical values within the range. For example, it should be considered that a description of a range from 1 to 6 has specifically disclosed sub-ranges, such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., as well as single numbers within the ranges, such as 1, 2, 3, 4, 5, and 6, wherever applicable. In addition, whenever a numerical range is referred to herein, it is meant to include any reference number (fractional or integer) within the indicated range.

In the present application, unless otherwise indicated, terms of orientation such as "upper" and "lower" are used to generally refer to the upper and lower directions of the light emitting device in actual use or operation, particularly the directions of the drawing, and "inner" and "outer" are used with respect to the outline of the light emitting device. The terms first, second, third and the like are used merely as labels, and do not impose numerical requirements or on the order of construction.

In the present application, the description of "the layer a is formed on the side of the layer B", "the layer a is formed on the side of the layer B away from the layer C", or the like may mean that the layer a is formed directly on the side of the layer B or the side of the layer B away from the layer C, that is, the layer a is in direct contact with the layer B, or that the layer a is formed with the layer B grounded on the side of the layer B or the side of the layer B away from the layer C, that is, other spacer structure layers may be formed between the layer a and the layer B. Similarly, "the layer A is arranged on one side of the layer B", "the layer A is arranged on one side of the layer B far away from the layer C" can be expressed as that the layer A is in direct contact with the layer B, or that other interval structure layers are arranged between the layer A and the layer B, and "the layer A is arranged between the layer B and the layer C" can be expressed as that the layer A is in direct contact with the layer B and the layer A is in direct contact with the layer C, or that one or more interval structure layers are arranged between the layer A and the layer B and one or more interval structure layers are arranged between the layer A and the layer C, or that the layer A and the layer B are in direct contact with one or more interval structure layers and the layer A and the layer C.

As used herein, the term "comprising" means "including but not limited to".

As used herein, the term "and/or" is used to describe an associative relationship of associative objects, and means that there may be three relationships, e.g., a and/or B, and that there may be a alone, a and B together, and B alone. Wherein A, B may be singular or plural.

As used herein, the term "at least one" means one (or more) and "plurality" means two (or more). The term "at least one", "at least one of" or the like refers to any combination of these items, including any combination of single or plural numbers. For example, "at least one of a, b, or c" or "at least one of a, b, and c" may each be expressed as a, b, c, a-b (i.e., a and b), a-c, b-c, or a-b-c, where a, b, and c may each be a single species or multiple species, respectively.

As used herein, "substituted or unsubstituted" means that the defined groups may or may not be substituted. When the defined groups are substituted, it is understood that the defined groups may be substituted with one or more substituents R ₀, R ₀ includes, but is not limited to, cyano, isocyano, nitro, halogen, alkyl containing 1 to 20 carbon atoms, heterocyclyl containing 3 to 20 ring atoms, aryl containing 6 to 20 ring atoms, -NR ' R ", silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, haloformyl, formyl, isocyanate, thiocyanate, isothiocyanate, hydroxy, trifluoromethyl, and the above groups may be further substituted with substituents acceptable in the art, it being understood that R ' and R" in-NR ' R "each independently include, but are not limited to, H, cyano, isocyano, nitro or halogen, alkyl containing 1 to 10 carbon atoms, heterocyclyl containing 3 to 20 ring atoms, or aryl containing 6 to 20 ring atoms.

In the present application, "aryl" means an aromatic hydrocarbon group derived by removing one hydrogen atom on the basis of an aromatic ring compound, which may be a monocyclic aryl group, or a condensed ring aryl group, or a polycyclic aryl group, at least one of which is an aromatic ring system for polycyclic ring species, and the aryl group of the present application may be substituted or unsubstituted, it being understood that a plurality of aryl groups may also be interrupted by short non-aromatic units (e.g., <10% of non-H atoms, such as C, N or O atoms), and in particular such acenaphthene, fluorene, 9-diaryl fluorene, triarylamine, diaryl ether systems should also be included in the definition of aryl groups. In some embodiments of the present application, the number of ring atoms of the aryl group is, for example, 6 to 30, 6 to 18, or 6 to 12, non-limiting examples include phenyl, biphenyl, terphenyl, naphthyl, anthryl, phenanthryl, fluoranthryl, triphenylenyl, pyrenyl, perylene, tetracenyl, fluorenyl, perylene, or acenaphthylenyl.

As used herein, "heteroaryl" refers to an aryl group in which at least one carbon atom is replaced by a non-carbon atom, which may be one or more of an N atom, an O atom, an S atom, and a Si atom, the number of heteroatoms being 1 to 20, and the heteroaryl group of the present application may be substituted or unsubstituted. In some embodiments of the application, the number of ring atoms of the heteroaryl group is, for example, 5-30, 5-20, 5-18, 5-12, or 5-10, non-limiting examples include thienyl, furanyl, pyrrolyl, diazolyl, triazolyl, imidazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridinyl, pyridazinyl, pyrazinyl, quinolinyl, isoquinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, benzothienyl, benzofuranyl, indolyl, pyrroloimidazolyl, pyrrolopyrrolyl, thienopyrrolyl, thienothiothienyl, furopyrrolyl, thienofuranyl, benzisoxazolyl, benzisothiazolyl, benzimidazolyl, phthalazinyl, phenanthridinyl, primary pyridyl, quinazolinonyl, dibenzothienyl, dibenzofuranyl, or carbazolyl.

As used herein, "hydrocarbyl" includes alkyl groups and unsaturated hydrocarbyl groups containing unsaturation. The hydrocarbon group of the application can be straight-chain hydrocarbon group, branched-chain hydrocarbon group, aliphatic cyclic hydrocarbon group or aliphatic heterocyclic hydrocarbon group, the aliphatic heterocyclic hydrocarbon group is that at least one carbon atom is replaced by a non-carbon atom on the basis of the aliphatic cyclic hydrocarbon group, the non-carbon atom can be one or more of N atom, O atom, S atom and Si atom, and the number of the hetero atoms is 1-20. In some embodiments of the present application, the straight or branched hydrocarbon group has 1 to 10, 1 to 5, or 1 to 3 carbon atoms, and non-limiting examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, n-heptyl, 1-methylheptyl, 2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, vinyl, 1-propenyl, 2-propenyl, or ethynyl. In some embodiments of the present application, the aliphatic cyclic hydrocarbon group or the aliphatic heterocyclic hydrocarbon group has 3 to 30, 3 to 20, or 3 to 10 carbon atoms, and non-limiting examples of the aliphatic cyclic hydrocarbon group include cyclopentyl, cyclohexyl, or cyclobutyl.

As used herein, "hydrocarbyloxy" refers to a group of the structure "-O-hydrocarbyl", i.e., a hydrocarbyl group as defined above is attached to other groups via an oxygen atom, and hydrocarbyloxy of the present application may be a linear hydrocarbyloxy or branched hydrocarbyloxy group having 1 to 10, 1 to 5, or 1 to 3 carbon atoms. In some embodiments of the application, non-limiting examples of linear or branched hydrocarbyloxy groups include methoxy (-O-CH ₃ or-OMe), ethoxy (-O-CH ₂CH₃ or-OEt), or tert-butoxy (-O-C (CH ₃)₃ or-OtBu).

In the existing light-emitting device, the light-emitting layer and the electronic functional layer form mechanical stress between interfaces through contact, but the mechanical performance of the mechanical stress is poor and unstable, so that the problem of premature separation of the light-emitting layer and the electronic functional layer occurs in the use process of the photoelectric device, and factors causing separation of the light-emitting layer and the electronic functional layer include but are not limited to mismatch of thermal expansion coefficients of layers and damage accumulation in use, so that the service life of the light-emitting device is reduced.

For QLEDs, the material of the electronic functional layer is typically a metal oxide (e.g., nano ZnO), which has inherent lattice defects, such as zinc vacancies (VZn), oxygen Vacancies (VO), zinc substituted oxygen (ZnO), and oxygen substituted zinc (OZn), which impart good charge transport capability to the metal oxide, but since the electronic functional layer is in contact with the light emitting layer, the metal oxide in the electronic functional layer is also in contact with the quantum dots in the light emitting layer, and the oxygen vacancy defects of the metal oxide cause fluorescence quenching of the quantum dots in contact therewith, thereby reducing the light emitting efficiency of the light emitting device. It is understood that too few lattice defects of the metal oxide adversely affect the charge transport capacity of the metal oxide.

In addition, the quantum dots in the light-emitting layer are connected with ligands, the ligands have the function of passivating the surface defects of the quantum dots to improve the performance stability of the quantum dots, but in the operation process of the QLED, the ligands on the surfaces of the quantum dots are easy to fall off, and the fallen ligands can drift under the action of an electric field, so that the chemical stability of the QLED is adversely affected, and the service life of the QLED is shortened. At least part of the metal oxide in the electronic functional layer is also connected with ligands, such as ligands of hydroxyl and the like, and the ligands on the surface of the metal oxide also have the problems of ligand falling and drifting, so that the chemical stability of the QLED is also adversely affected, and the service life of the QLED is further shortened.

Based on this, the embodiment of the present application provides a light emitting device, which may be a positive structure or an inverted structure, as shown in fig. 1, the light emitting device 10 includes an anode 11, a cathode 12, a light emitting layer 13, an auxiliary layer 14, and an electronic functional layer 15, wherein the anode 11 is disposed opposite to the cathode 12, the electronic functional layer 15 is disposed between the cathode 12 and the light emitting layer 13, the auxiliary layer 14 is disposed between the electronic functional layer 15 and the light emitting layer 13, the auxiliary layer 14 includes a connection group, and the connection group is a first group of a structure shown by the following general formula (I) and/or a second group of a structure shown by the following general formula (II):

In the general formula (I) and the general formula (II), R ₁、R₂、R₅ and R ₆ are independently selected from one or more of hydrogen, deuterium, tritium, substituted or unsubstituted C1-C10 linear hydrocarbon or branched hydrocarbon group, substituted or unsubstituted aliphatic cyclic hydrocarbon group with 3-30 ring atoms, substituted or unsubstituted aryl with 6-30 ring atoms and substituted or unsubstituted heteroaryl with 5-30 ring atoms;

In the light emitting device 10 of the embodiment of the application, the auxiliary layer 14 is arranged between the electronic functional layer 15 and the light emitting layer 13, the auxiliary layer 14 comprises the connecting groups, the connecting groups are respectively connected with the electronic functional layer 15 and the light emitting layer 13, the connection tightness between the light emitting layer 13 and the electronic functional layer 15 can be improved, the risk of separation of the electronic functional layer 15 and the light emitting layer 13 is reduced, and therefore the service life of the light emitting device 10 is effectively prolonged.

In some embodiments of the present application, the substituted or unsubstituted C1-C10 linear or branched hydrocarbon group is selected from C1-C3 linear or branched hydrocarbon groups, and/or the substituted or unsubstituted aliphatic cyclic hydrocarbon group having 3-30 ring atoms is selected from 3-10 aliphatic cyclic hydrocarbon groups, and/or the substituted or unsubstituted aliphatic heterocyclic hydrocarbon group having 3-30 ring atoms is selected from 3-10 aliphatic heterocyclic hydrocarbon groups, and/or the substituted or unsubstituted aryl group having 6-30 ring atoms is selected from 6-18 ring atoms, and/or the substituted or unsubstituted heteroaryl group having 5-30 ring atoms is selected from 5-18 ring atoms.

In some embodiments of the application, the linking group is selected from one or more of the following groups:

In the light emitting device 10 of the embodiment of the application, the electronic functional layer 15 may have a single-layer structure or a multi-layer structure, and the thickness of the electronic functional layer 15 is, for example, 10nm to 100nm. The electron functional layer 15 comprises, for example, one or more of an electron injection layer, an electron transport layer, and a hole blocking layer, and for the electron functional layer 15 comprising an electron injection layer, an electron transport layer, and a hole blocking layer, the electron transport layer is located between the electron injection layer and the hole blocking layer and the electron injection layer is closer to the cathode 12 than the hole blocking layer, for the electron functional layer 15 comprising an electron injection layer and an electron transport layer, the electron injection layer is closer to the cathode 12 than the electron transport layer, and for the electron functional layer 15 comprising an electron transport layer and a hole blocking layer, the electron transport layer is closer to the cathode 12 than the hole blocking layer. As an example, the electron functional layer 15 is a single-layer structure, and the electron functional layer 15 is an electron transport layer.

To further enhance the optoelectronic performance and device lifetime of the light emitting device 10, in some embodiments of the present application, the material of the electronically functional layer comprises a first inorganic compound to which the linking group is attached, the first inorganic compound comprising one or more of an undoped first metal oxide, a doped second metal oxide, a group II-VI semiconductor material, a group III-V semiconductor material, and a group I-III-VI semiconductor material. Wherein the undoped first metal oxide is selected from one or more of ZnO, tiO ₂、SnO₂、BaO、Ta₂O₃、Al₂O₃ and ZrO ₂, and/or the doped second metal oxide is a host metal oxide doped with a first doping element, the host metal oxide is selected from one or more of ZnO, tiO ₂、SnO₂、BaO、Ta₂O₃、Al₂O₃ or ZrO ₂, the first doping element is selected from one or more of Mg, ca, zr, W, ga, li, al, ti, Y, in and Sn, and/or the mole percentage of the first doping element in the doped second metal oxide is below 50%, and/or the group II-VI semiconductor material is selected from one or more of ZnS, znSe and CdS, and/or the group III-V semiconductor material is selected from one or more of InP and GaP, and/or the group I-III-VI semiconductor material is selected from one or more of CuInS and CuGaS.

The doped second metal oxide includes, but is not limited to, one or more of zinc magnesium oxide, zinc calcium oxide, zinc zirconium oxide, zinc gallium oxide, zinc aluminum oxide, zinc lithium oxide, zinc titanium oxide, yttrium zinc oxide, indium tin oxide, and titanium lithium oxide, such as one or more of Zn_(1-x)Mg_xO、Zn_(1-x)Ca_xO、Zn_(1-x)Zr_xO、Zn_(1-x)W_xO、Zn_(1-x)Y_xO、Zn_(1-x)Ga_xO、Zn_(1-x)Al_xO、Zn_(1-x)Li_xO、Al_(1-x)Zn_xO、Zn_(1-x)Ti_xO、Zn_(1-x)Y_xO、In_(1-x)Sn_xO and Ti _(1-x)Li_x O, wherein 0< x.ltoreq.0.5.

In some embodiments of the present application, the first inorganic compound is a nanomaterial, and the first inorganic compound may be in the form of nanoparticles, nanorods, or nanoplatelets, and when the first inorganic compound is a nanoparticle, the average particle size is 3nm to 10nm.

It will be appreciated that when the electronic functional layer 15 comprises a plurality of materials and the electronic functional layer 15 is a multi-layer structure, the plurality of materials may all be in the same layer, or in different layers, respectively, or in part in the same layer.

In the light emitting device 10 of the embodiment of the application, the light emitting layer 13 may have a single-layer structure or a multi-layer structure, and the thickness of the light emitting layer 13 is, for example, 10nm to 100nm. In some embodiments of the present application, the light emitting device 10 is a QLED, and the material of the light emitting layer 13 includes quantum dots, and the linking group is connected to the quantum dots. Quantum dots include, but are not limited to, one or more of red, green, and blue quantum dots, and quantum dots include, but are not limited to, one or more of single component quantum dots, core-shell structure quantum dots, inorganic perovskite quantum dots, organic perovskite quantum dots, and organic-inorganic hybrid perovskite quantum dots. The average particle diameter of the quantum dots may be 2nm to 20nm, and may be, for example, 2nm, 4nm, 6nm, 8nm, 10nm, 12nm, 15nm, 20nm, or a value between any two of the foregoing values.

For single component quantum dots and core-shell structured quantum dots, the material of the single component quantum dot, the material of the core-shell structured quantum dot, or the material of the shell of the core-shell structured quantum dot includes, but is not limited to, at least one of a group II-VI compound selected from one or more of CdS、CdSe、CdTe、ZnS、ZnSe、ZnTe、ZnO、HgS、HgSe、HgTe、CdSeS、CdSeTe、CdSTe、ZnSeS、ZnSeTe、ZnSTe、HgSeS、HgSeTe、HgSTe、CdZnS、CdZnSe、CdZnTe、CdHgS、CdHgSe、CdHgTe、HgZnS、HgZnSe、HgZnTe、CdZnSeS、CdZnSeTe、CdZnSTe、CdHgSeS、CdHgSeTe、CdHgSTe、HgZnSeS、HgZnSeTe and HgZnSTe, a group III-V compound selected from one or more of GaN、GaP、GaAs、GaSb、AlN、AlP、AlAs、AlSb、InN、InP、InAs、InSb、GaNP、GaNAs、GaNSb、GaPAs、GaPSb、AlNP、AlNAs、AlNSb、AlPAs、AlPSb、InNP、InNAs、InNSb、InPAs、InPSb、GaAlNP、GaAlNAs、GaAlNSb、GaAlPAs、GaAlPSb、GaInNP、GaInNAs、GaInNSb、GaInPAs、GaInPSb、InAlNP、InAlNAs、InAlNSb、InAlPAs and InAlPSb, and a group IV-VI compound selected from one or more of SnS、SnSe、SnTe、PbS、PbSe、PbTe、SnSeS、SnSeTe、SnSTe、PbSeS、PbSeTe、PbSTe、SnPbS、SnPbSe、SnPbTe、SnPbSSe、SnPbSeTe and SnPbSTe, a group IV-VI compound selected from one or more of CuInS, cuInSe and AgInS. The chemical formula provided for the material of the single-component quantum dot, the material of the core of the quantum dot with the core-shell structure, or the material of the shell of the quantum dot with the core-shell structure only shows the element composition, and the content of each element is not shown, for example, cdZnSe only shows that the material consists of three elements of Cd, zn and Se, and Cd _xZn_(1-x) Se and 0< x <1 are corresponding if the content of each element is shown.

For inorganic perovskite quantum dots, the structural formula of the inorganic perovskite quantum dots is AMX ₃, wherein A is Cs ⁺, M is a divalent metal cation, M comprises, but is not limited to, Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺ or Eu ²⁺, and X is a halogen anion, including, but not limited to, cl ^-、Br^- or I ^-.

For organic perovskite quantum dots, the structural formula hey CMX ₃ of the organic perovskite quantum dots, wherein C is a formamidino group, M is a divalent metal cation, M includes but is not limited to Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺ or Eu ²⁺, and X is a halogen anion, including but not limited to Cl ^-、Br^- or I ^-.

For the organic-inorganic hybrid perovskite quantum dots, the structural general formula of the organic-inorganic hybrid perovskite quantum dots is BMX ₃, wherein B is selected from organic amine cations, the organic amine cations comprise but are not limited to CH ₃(CH₂)_n-2NH³⁺ (n is more than or equal to 2) or NH ₃(CH₂)_nNH₃ ²⁺ (n is more than or equal to 2), M is a divalent metal cation, M comprises but is not limited to Pb²⁺、Sn²⁺、Cu²⁺、Ni²⁺、Cd²⁺、Cr²⁺、Mn²⁺、Co²⁺、Fe²⁺、Ge²⁺、Yb²⁺ or Eu ²⁺, and X is a halogen anion, including but not limited to Cl ^-、Br^- or I ^-.

When the light-emitting device is a QLED, the connecting group is connected with the first inorganic compound in the electronic functional layer and the quantum dot in the light-emitting layer, namely, the connecting group is used as a ligand of the first inorganic compound in one surface of the electronic functional layer close to the light-emitting layer, and the connecting group is also used as a ligand of the quantum dot in one surface of the light-emitting layer close to the electronic functional layer, so that the number of the quantum dots in direct contact with the first inorganic compound is reduced or the direct contact between the first inorganic compound and the quantum dot is avoided, the oxygen vacancy defect of the first inorganic compound in one surface of the electronic functional layer close to the light-emitting layer is reduced, the fluorescence quenching effect of the oxygen vacancy defect of the first inorganic compound on the quantum dot is reduced or eliminated, the light-emitting efficiency of the light-emitting device is improved, and in addition, the first inorganic compound in the electronic functional layer still maintains the original lattice defect, and the electronic functional layer is endowed with good electron transmission performance.

It is understood that the surface of the quantum dot inside the light emitting layer may also have first ligands attached. The first ligand may be one or more of the ligands common in the art including, but not limited to, fatty carboxylic acid ligands of C ₁～C₃₀, aromatic carboxylic acid ligands of C ₆～C₃₀, fatty thiol ligands of C ₁～C₃₀, thiol aromatic ligands of C ₆～C₃₀, fatty amine ligands of C ₁～C₃₀, aromatic amine ligands of C ₆～C₃₀, fatty phosphine ligands of C ₁～C₃₀, aromatic phosphine ligands of C ₆～C₃₀, and aromatic phosphate ligands of C ₆～C₃₀, and halogen ligands.

Wherein the fatty carboxylic acid ligands include, but are not limited to, one or more of octanoic acid, nonanoic acid, decanoic acid, undecanoic acid, dodecanoic acid, tetradecanoic acid, hexadecanoic acid, octadecanoic acid, eicosanoic acid, tetracosanoic acid, hexacosanoic acid, oleic acid, linoleic acid, arachic acid, arachidonic acid, erucic acid, and docosahexaenoic acid, and the aromatic carboxylic acid ligands include, but are not limited to, one or more of benzoic acid, diphenic acid, and 1-naphthoic acid. The aliphatic thiol ligands include, but are not limited to, one or more of hexanethiol, octanethiol, nonanethiol, decanethiol, undecanethiol, dodecanethiol, hexadecanethiol and octadecanethiol, and the thiol aromatic ligands include, but are not limited to, one or more of benzenethiol, trityl thiol and p-terphenyl-4, 4' -dithiol. The fatty amine ligands include, but are not limited to, one or more of hexylamine, octylamine, dioctylamine, trioctylamine, nonylamine, decylamine, dodecylamine, tridecylamine, dodecylamine, pentadecylamine, hexadecylamine, heptadecylamine, octadecylamine, and oleylamine, and the aromatic amine ligands include, but are not limited to, one or more of aniline, indenylpropylamine, 4-octylaniline, and benzidine. The aliphatic phosphine ligands include, but are not limited to, one or more of trimethylphosphine, triethylphosphine, tripropylphosphine, tributylphosphine, trihexylphosphine, trioctylphosphine, tridecylphosphine, tributylphosphine oxide, trihexylphosphine oxide, trioctylphosphine oxide, and tridecylphosphine oxide, the aromatic phosphine ligands include, but are not limited to, one or more of bis (2-diphenylphosphinoethyl) phenylphosphine and triphenylphosphine oxide, and the aromatic phosphate ligands include, but are not limited to, one or more of tetraethyl p-xylylene diphosphate and ethyl diphenylphosphate. Halogen ligands include, but are not limited to, -Cl, -F, -I, or-Br.

In order to further enhance the optoelectronic performance and device lifetime of the light emitting device 10, in some embodiments of the present application, the material of the anode 11 and the material of the cathode 12 are selected from one or more of a metal, a carbon material, and a third metal oxide, independently of each other. Wherein the metal includes, but is not limited to, one or more of Al, ag, cu, mo, au, ba, pt, ca, ir, ni and Mg, the carbon material includes, but is not limited to, one or more of graphite, carbon nanotubes, graphene and carbon fibers, the third metal oxide may be doped or undoped, the doped third metal oxide includes, but is not limited to, one or more of Indium Tin Oxide (ITO), fluorine doped tin oxide (FTO), tin antimony oxide (ATO), aluminum doped zinc oxide (AZO), gallium doped zinc oxide (GZO), indium doped zinc oxide (IZO) and magnesium doped zinc oxide (MZO), and the undoped third metal oxide includes, but is not limited to, one or more of TiO ₂、SnO₂, znO and In ₂O₃.

It should be noted that the anode 11 or the cathode 12 may also be a composite electrode, where the composite electrode has a structure similar to a "sandwich", the materials of the upper layer and the bottom layer are respectively doped or undoped second metal oxides, and the material of the middle layer is one or more of metals, for example AZO/Ag/AZO、AZO/Al/AZO、ITO/Ag/ITO、ITO/Al/ITO、ZnO/Ag/ZnO、ZnO/Al/ZnO、TiO₂/Ag/TiO₂、TiO₂/Al/TiO₂、TiO₂/Ag/TiO₂ and TiO ₂/Al/TiO₂. The thickness of the anode 11 and the cathode 12 is, for example, independently selected from 20nm to 300nm.

In order to promote electron-hole transport equilibrium, thereby further improving the optoelectronic performance and device lifetime of light emitting device 10, in some embodiments of the present application, with continued reference to fig. 1, light emitting device 10 further comprises a hole functional layer 16, hole functional layer 16 being disposed between light emitting layer 13 and anode 11.

The hole function layer 16 may have a single-layer structure or a multi-layer structure, and the thickness of the hole function layer 16 is, for example, 10nm to 100nm. The hole-functional layer 16 includes, for example, one or more of a hole-injecting layer, a hole-transporting layer, and an electron-blocking layer, and for the hole-functional layer 16 including a hole-injecting layer, a hole-transporting layer, and an electron-blocking layer, the hole-transporting layer is located between the hole-injecting layer and the electron-blocking layer and the hole-injecting layer is located closer to the anode 11 than the electron-blocking layer, and for the hole-functional layer 16 including a hole-transporting layer and an electron-blocking layer, the hole-transporting layer is located closer to the anode 11 than the electron-blocking layer. As an example, with continued reference to fig. 1, the hole-functional layer 16 is composed of a hole-injecting layer 161 and a hole-transporting layer 162 that are stacked, and the hole-injecting layer 161 is closer to the anode 11 than the hole-transporting layer 162.

Wherein the material of the hole function layer 16 includes, but is not limited to, undoped second inorganic compound, doped third inorganic compound, poly (3, 4-ethylenedioxythiophene) poly (styrenesulfonic acid) (PEDOT: PSS, CAS number 155090-83-8), copper phthalocyanine (CAS number 147-14-8), titanylphthalocyanine (CAS number 26201-32-1), 2,3,5, 6-tetrafluoro-7, 7', 8' -tetracyanodimethyl-p-benzoquinone (CAS number 29261-4), 2,3,6,7,10, 11-hexacyano-1, 4,5,8,9, 12-hexaazabenzophenanthrene (CAS number 105598-27-4) Polyaniline (CAS number 25233-30-1), polypyrrole (CAS number 30604-81-0), 3-hexyl-substituted polythiophene (CAS number 104934-50-1), poly (9-vinylcarbazole) (PVK for short, CAS number 25067-59-8), 4 '-bis (9-carbazole) biphenyl (CBP for short, CAS number 58328-31-7), poly [ bis (4-phenyl) (4-butylphenyl) amine ], 4' -cyclohexylbis [ N, N-bis (4-methylphenyl) aniline ] (TAPC for short, CAS number 58473-78-2), and, Poly [ (9, 9-dioctylfluorenyl-2, 7-diyl) -co- (4, 4' - (N- (4-sec-butylphenyl) diphenylamine) ] (TFB for short, CAS number 220797-16-0), poly [ (N, N ' - (4-N-butylphenyl) -N, N ' -diphenyl-1, 4-phenylenediamine) -ALT- (9, 9-di-N-octylfluorenyl-2, 7-diyl) ] (CAS number 223569-31-1), 4' -tris (N-3-methylphenyl-N-phenylamino) triphenylamine (CAS number 124729-98-2), 4' -tris (carbazole-9-yl) triphenylamine (TCTA for short, CAS number 139092-78-7), 4,4' -tris (2-naphthylphenylamino) triphenylamine (CAS No. 185690-41-9), N ' -diphenyl-N, N ' - (1-naphthyl) -1,1' -biphenyl-4, 4' -diamine (abbreviated as NPB, CAS No. 123847-85-8), N ' -diphenyl-N, N ' -bis (3-methylphenyl) -1,1' -biphenyl-4, 4' -diamine (abbreviated as TPD, CAS No. 65181-78-4), N ' -bis [4- (diphenylamino) phenyl ] -N, N ' -diphenyl benzidine (CAS No. 209980-53-0), One or more of N, N '-bis (3-methylphenyl) -N, N' -diphenyl-9, 9-spirobifluorene-2, 7-diamine (abbreviated as Spiro-TPD, CAS No. 1033035-83-4), N2, N7-bis-1-naphthyl-N2, N7-diphenyl-9, 9 '-spirodi [ 9H-fluorene ] -2, 7-diamine (CAS No. 932739-76-9), poly [ bis (4-phenyl) (2, 4, 6-trimethylphenyl) amine ] (abbreviated as pta, CAS No. 1333317-99-9) and 2,2',7 '-tetrakis [ N, N-bis (4-methoxyphenyl) amino ] -9,9' -spirobifluorene (abbreviated as Spiro-tad, CAS No. 207739-72-8).

Wherein the undoped second inorganic compound is selected from one or more of graphene, C60, nickel oxide (e.g., niO), molybdenum oxide (e.g., moO ₃), tungsten oxide (e.g., WO ₃), vanadium oxide (e.g., V ₂O₅), P-type gallium nitride, chromium oxide (e.g., cr ₂O₃), copper oxide (e.g., cuO or Cu ₂ O), copper sulfide (e.g., cuS), molybdenum sulfide (e.g., moS ₂), and tungsten sulfide (e.g., WS ₂), and/or the doped third inorganic compound is a second doping element doped host inorganic compound selected from one or more of graphene, C60, nickel oxide (e.g., niO), molybdenum oxide (e.g., moO ₃), tungsten oxide (e.g., WO ₃), vanadium oxide (e.g., V ₂O₅), P-type gallium nitride, chromium oxide (e.g., cr ₂O₃), copper oxide (e.g., cuO or Cu ₂ O), copper sulfide (e.g., cuS), molybdenum sulfide (e.g., moS ₂), and tungsten sulfide (e.g., WS ₂), and/or the second doping element is selected from one or more of the group consisting of graphene, nickel, tungsten, vanadium, molybdenum, and molybdenum.

It will be appreciated that when the hole function layer 16 comprises multiple materials and the hole function layer 16 is a multi-layer structure, the multiple materials may all be in the same layer, or in different layers, respectively, or in part in the same layer. For example, when the first hole-functional layer 16 is composed of a hole-injecting layer and a hole-transporting layer which are stacked, the material of the hole-functional layer 16 includes PEDOT: PSS and TFB, which are respectively in different layers, the material of the hole-injecting layer is PEDOT: PSS, and the material of the hole-transporting layer is TFB.

The embodiment of the application also provides a preparation method of the light-emitting device, which can be used for preparing any one of the light-emitting devices, and comprises the following steps:

S1, providing a bottom electrode, and forming a light-emitting layer on one surface of the bottom electrode;

s2, forming a top electrode on one surface of the light-emitting layer, which is far away from the bottom electrode.

When the light-emitting device is of a positive structure, the bottom electrode is an anode and the top electrode is a cathode, and the preparation method of the light-emitting device further comprises the steps of depositing a solution containing an auxiliary functional material on one surface of the light-emitting layer far away from the bottom electrode so as to connect at least part of the auxiliary functional material with the light-emitting layer, forming an electronic functional layer on one surface of the light-emitting layer where the solution is deposited, and forming an auxiliary layer between the electronic functional layer and the light-emitting layer. Or when the light emitting device is of an inverted structure, the bottom electrode is a cathode and the top electrode is an anode, and before the step of forming the light emitting layer on one side of the bottom electrode, the preparation method of the light emitting device further comprises the steps of forming an electronic functional layer on one side of the bottom electrode, then depositing a solution containing an auxiliary functional material on one side of the electronic functional layer far away from the bottom electrode so as to connect at least part of the auxiliary functional material with the electronic functional layer, and forming an auxiliary layer between the electronic functional layer and the light emitting layer after forming the light emitting layer on one side of the electronic functional layer where the solution is deposited. The structural composition of the anode, cathode, light-emitting layer, electron-functional layer and auxiliary layer is described above.

R ₁ to R ₈ are all described hereinbefore.

In the preparation method of the light-emitting device according to the embodiment of the application, the auxiliary functional material contains two mercapto groups (-SH) and at least one carbon-carbon double bond, and has a special electron cloud structure and sulfur atom coordination characteristic, for the light-emitting device with a positive structure, after a solution containing the auxiliary functional material is deposited on one side of the light-emitting layer, sulfur atoms in one mercapto group in the auxiliary functional material are connected to one side of the light-emitting layer in a coordination bond form, for example, are coordinately connected with metal atoms of quantum dots in the light-emitting layer, based on a steric hindrance effect, the other mercapto group in the auxiliary functional material is not attached to the surface of the light-emitting layer, after the electronic functional layer is formed, sulfur atoms in the other mercapto group are coordinately connected to one side of the electronic functional layer close to the light-emitting layer, for example, and oxygen space in the electronic functional layer are coordinately connected to form an auxiliary layer between the light-emitting layer and the electronic functional layer, for the light-emitting device with an inverted structure, after the solution containing the auxiliary functional material is deposited on one side of the electronic functional layer, sulfur atoms in the auxiliary functional material are connected to the electronic functional layer in a coordination bond form, and the sulfur atoms in the electronic functional layer are effectively connected to the other side of the electronic functional layer in a coordination bond form between the electronic functional layer and the light-emitting layer and the electronic functional layer.

In the method for manufacturing the light emitting device according to the embodiment of the present application, the deposition method of the solution includes, but is not limited to, one or more of spin coating, printing, blade coating, dip-coating, dipping, spray coating, roll coating, casting, slit coating, and bar coating.

In order to further enhance the optoelectronic properties and device lifetime of the resulting light emitting device, in some embodiments of the present application, the auxiliary functional material is selected from one or more of the group consisting of compounds having CAS numbers 34725-64-9, compounds having CAS numbers 54462-80-5, compounds having CAS numbers 111900-12-0, compounds having CAS numbers 122913-78-4, and compounds having CAS numbers 5853-57-6.

In order to further improve the device lifetime of the resulting light emitting device, in some embodiments of the application the mass of the auxiliary functional material is 3% -5%, e.g. 3%, 4%, 5% or a value between any two of the foregoing percentages of the total mass of the solution, and/or the deposition thickness of the solution is 5-10 nm, e.g. 5nm, 6nm, 7nm, 8nm, 9nm, 10nm or a value between any two of the foregoing values.

In order to further improve the device lifetime of the manufactured light emitting device, in some embodiments of the present application, when the light emitting device is in a front-mounted structure, the method for manufacturing the light emitting device further includes removing the auxiliary functional material not connected to the light emitting layer after the step of depositing the solution containing the auxiliary functional material on the side of the light emitting layer away from the bottom electrode and before the step of forming the electronic functional layer. Or when the light emitting device is of an inverted structure, the method for manufacturing the light emitting device further comprises the step of removing the auxiliary functional material which is not connected with the electronic functional layer after the step of depositing the solution containing the auxiliary functional material on the side of the electronic functional layer away from the bottom electrode and before the step of forming the light emitting layer. The method for removing the auxiliary functional material which is not connected with the electronic functional layer or the luminescent layer comprises the steps of cleaning one surface of the electronic functional layer or the luminescent layer deposited with the solution by using a first solvent, and further, after the step of cleaning, the preparation method of the luminescent device can further comprise the steps of drying one surface of the electronic functional layer or the luminescent layer deposited with the solution to remove the residual first solvent, wherein the drying treatment comprises one or more of natural air drying treatment, heat treatment, vacuum drying treatment, laser annealing treatment, electron beam annealing treatment, atomic annealing treatment and microwave irradiation annealing treatment.

In some embodiments of the present application, the solvent of the solution is a second solvent, the first solvent and the second solvent are independently selected from one or more of alkanes, aromatic hydrocarbons, halogenated alkanes, alcohols, ethers, furans, pyridines, and amides, wherein alkanes include but are not limited to one or more of nonane, decane, dodecane, terpenes, butylcyclohexane, N-octane, N-hexane, N-heptane, N-nonane, N-decane, cyclohexane, and cyclopentane, aromatic hydrocarbons include but are not limited to one or more of diethylbenzene, trimethylbenzene, propylbenzene, isopropylbenzene, p-toluenes, butylbenzene, and 1-methylnaphthalene or indene, halogenated alkanes include but are not limited to one or more of methylene chloride, chloroform, and carbon tetrachloride, alcohols include but are not limited to methanol, ethanol, propanol, butanol, ethylene glycol, and glycerol, ethers include but are not limited to ethylene glycol monomethyl ether, furans include but are not limited to tetrahydrofuran include but are not limited to pyridine, include but are not limited to N-methylnaphthalene, and amides. As an example, the first solvent and/or the second solvent is selected from methanol.

In order to promote electron-hole transport balance and further improve the photoelectric performance and the service life of the light-emitting device, in some embodiments of the present application, before the step of forming a light-emitting layer on one surface of the bottom electrode when the light-emitting device is in a positive structure, the preparation method of the light-emitting device further comprises the steps of forming a hole function layer on one surface of the bottom electrode, forming the light-emitting layer on one surface of the hole function layer away from the bottom electrode, or forming a hole function layer on one surface of the light-emitting layer away from the bottom electrode between the step S1 and the step S2 when the light-emitting device is in an inverted structure, and forming a top electrode on one surface of the hole function layer away from the light-emitting layer.

It should be noted that, in addition to the auxiliary layer, the preparation method of the other film layers in the light emitting device includes, but is not limited to, chemical and/or physical methods. Among them, chemical methods include, but are not limited to, one or more of chemical vapor deposition, continuous ion layer adsorption and reaction, anodic oxidation, electrolytic deposition, and co-precipitation. The physical methods include, but are not limited to, physical plating methods including, but not limited to, one or more of thermal evaporation plating, electron beam evaporation plating, magnetron sputtering, multi-arc ion plating, physical vapor deposition, atomic layer deposition, and pulsed laser deposition, and solution methods including, but not limited to, one or more of spin coating, printing, doctor blading, dip-coating, dipping, spray coating, roll coating, casting, slot coating, and bar coating.

After each film layer of the light-emitting device is prepared, a packaging treatment process is required, and the packaging treatment can be carried out by adopting a common machine packaging or manual packaging, wherein in the packaging treatment environment, the oxygen content and the water content are both lower than 0.1ppm so as to ensure the stability of the light-emitting device. In order to further improve the performance stability of the light emitting device, in some embodiments of the present application, the encapsulation is performed using epoxy.

The embodiment of the application also provides electronic equipment, which comprises the light-emitting device prepared by any one of the preparation methods of the light-emitting devices. The electronic device may be, for example, any electronic product having a display function, including but not limited to, a smart phone (smart phone), a tablet computer (tablet personal computer), a mobile phone (mobile phone), a video phone, an electronic book reader (e-book reader), a laptop (labop PC), a netbook (netbook computer), a workstation (workstation), a server, a personal digital assistant (personal DIGITAL ASSISTANT), a portable media player (portable multimedia player), an MP3 player, a mobile medical machine, a camera, a game console, a digital camera, a car navigator, an electronic billboard, an automated teller machine, a smart bracelet, a smart watch, a Virtual Reality (VR) device, or a wearable device (wearabledevice).

The technical solutions and effects of the present application will be described in detail by way of specific examples, comparative examples and experimental examples, which are only some examples of the present application, and are not intended to limit the present application in any way.

Example 1

The embodiment provides a light emitting device and a preparation method thereof, wherein the light emitting device is a quantum dot light emitting diode with a forward structure, as shown in fig. 1, in a direction from bottom to top, the light emitting device 10 includes an anode 11, a hole functional layer 16, a light emitting layer 13, an auxiliary layer 14, an electron functional layer 15 and a cathode 12, which are sequentially stacked, wherein the hole functional layer 16 is composed of a hole injection layer 161 and a hole transport layer 162 which are stacked, the hole injection layer 161 is closer to the anode 11 than the hole transport layer 162, and the electron functional layer 15 is in a single-layer structure. The light emitting area of the light emitting device was 2cm long by 2cm wide.

The materials and thicknesses of the various layers in the light emitting device 10 are as follows:

the anode 11 is made of ITO, and the thickness of the anode 11 is 120nm;

the cathode 12 is made of Ag, and the thickness of the cathode 12 is 60nm;

The luminescent layer 13 is made of CdSeS (core)/ZnS (shell) quantum dots, oleic acid ligand is connected with the CdSeS/ZnS quantum dots, the luminescent color is green, and the thickness of the luminescent layer 13 is 70nm;

The material of the hole injection layer 161 is PEDOT PSS, and the thickness of the hole injection layer 161 is 80nm;

The material of the hole transport layer 162 is TFB, and the thickness of the hole transport layer 162 is 70nm;

The material of the electronic functional layer 15 is nano ZnO (the average grain diameter is 5 nm), and the thickness of the electronic functional layer 15 is 50nm;

The auxiliary layer 14 includes a linking group having a structure represented by the following formula (1.1):

the preparation method of the light-emitting device in this embodiment includes the following steps:

S1.1, providing a substrate, sputtering ITO on one surface of the substrate to obtain an ITO layer, dipping a small amount of soapy water on the surface of the ITO layer by using a cotton swab to wipe the surface of the ITO layer so as to remove impurities visible to the naked eyes on the surface, sequentially ultrasonically cleaning the substrate comprising the ITO by using deionized water, acetone for 15min, ethanol for 15min and isopropanol for 15min, and performing ultraviolet-ozone surface treatment for 15min after drying to obtain the substrate comprising an anode;

S1.2, spin-coating PEDOT with mass fraction of 2.8% in PSS water solution on one surface of the anode far from the substrate in an air environment at normal temperature and normal pressure, and then placing the substrate in a constant-temperature heat treatment at 150 ℃ to be solidified into a film so as to obtain a hole injection layer;

s1.3, spin-coating TFB-chlorobenzene solution with the concentration of 6.5mg/mL on the surface of the hole injection layer far away from the anode in an argon environment at normal temperature and normal pressure, and then placing the film at a constant temperature for heat treatment at 170 ℃ to solidify the film to obtain a hole transport layer;

S1.4, spin-coating a CdSeS/ZnS quantum dot-n-octane solution with the concentration of 30mg/mL on one surface of the hole transport layer far away from the hole injection layer in an argon environment at normal temperature and normal pressure, and then placing the solution in a constant-temperature heat treatment mode at 80 ℃ to solidify the solution into a film to obtain a luminescent layer;

S1.5, spin-coating a solution containing an auxiliary functional material on one surface of a luminescent layer far away from a hole transmission layer in an argon environment at normal temperature and normal pressure, wherein the auxiliary functional material is a compound with CAS number of 34725-64-9, the solvent is methanol, the mass of the auxiliary functional material accounts for 5% of the total mass of the solution, the spin-coating thickness is 5nm, and standing for 10min;

S1.6, placing the prefabricated device after the step S1.5 in an evaporation bin with the air pressure of 4 multiplied by 10 ^-6 mbar, thermally evaporating Ag on the surface of the electronic functional layer, which is far away from the light-emitting layer, through a mask plate to obtain a cathode, and then packaging to obtain the light-emitting device.

Wherein the compound having CAS number 34725-64-9 has a structure represented by the following formula (1.2):

Example 2

The embodiment provides a light emitting device and a method for manufacturing the same, which are different from those of embodiment 1 only in the content of the linking group in the auxiliary layer.

Compared with the preparation method of the light-emitting device in example 1, the preparation method of the light-emitting device in this example is different in that the "mass of the auxiliary functional material in step S1.5 is 5% of the total mass of the solution" is replaced with the "mass of the auxiliary functional material is 10% of the total mass of the solution".

Example 3

The present embodiment provides a light emitting device and a method of manufacturing the same, which are different from the light emitting device of embodiment 1 only in that the connection group in the auxiliary layer has a structure represented by the following formula (3.1).

The manufacturing method of the light emitting device in this example is different from the manufacturing method of the light emitting device in example 1 in that "the compound having the CAS number 34725-64-9" in step S1.5 is replaced with "the compound having the CAS number 54462-80-5" as the auxiliary functional material.

Wherein the compound having CAS number 54462-80-5 has a structure represented by the following formula (3.2):

Example 4

The present embodiment provides a light emitting device and a method of manufacturing the same, which are different from the light emitting device of embodiment 1 only in that the connection group in the auxiliary layer has a structure represented by the following formula (4.1).

The manufacturing method of the light emitting device in this example is different from the manufacturing method of the light emitting device in example 1 in that "the compound having the CAS number 34725-64-9" in step S1.5 is replaced with "the compound having the CAS number 111900-12-0" as the auxiliary functional material.

Wherein the compound having CAS number 111900-12-0 has a structure represented by the following formula (4.2):

Example 5

The present embodiment provides a light emitting device and a method of manufacturing the same, which are different from the light emitting device of embodiment 1 only in that the connection group in the auxiliary layer has a structure represented by the following formula (5.1).

The manufacturing method of the light emitting device in this example is different from the manufacturing method of the light emitting device in example 1 in that "the compound having the CAS number 34725-64-9" in step S1.5 is replaced with "the compound having the CAS number 122913-78-4" as the auxiliary functional material.

Wherein the compound having CAS number 122913-78-4 has a structure represented by the following formula (5.2):

Example 6

The present embodiment provides a light emitting device and a method of manufacturing the same, which is different from the light emitting device of embodiment 1 only in that the connection group in the auxiliary layer has a structure represented by the following formula (6.1).

The manufacturing method of the light emitting device in this example is different from the manufacturing method of the light emitting device in example 1 in that "the compound having the CAS number 34725-64-9" in step S1.5 is replaced with "the compound having the CAS number 5853-57-6" as the auxiliary functional material.

Wherein the compound having CAS number 5853-57-6 has a structure represented by the following formula (6.2):

Comparative example

The present comparative example provides a light emitting device and a method of manufacturing the same, which is different from the light emitting device of example 1 only in that an auxiliary layer is omitted.

Compared with the preparation method of the light-emitting device in example 1, the preparation method of the light-emitting device in the comparative example is characterized in that the preparation method of the light-emitting device is replaced by the step S1.5 of spin-coating a 30mg/mL nano ZnO-ethanol solution on the surface of the light-emitting layer far away from the hole transport layer under the argon atmosphere at normal temperature and normal pressure, and then performing constant temperature heat treatment at 80 ℃ to solidify the film to obtain an electronic functional layer.

Experimental example

The performance of the light emitting devices packaged in examples 1 to 6 and comparative example were detected by IVL optical characteristic measurement devices (including marine optical USB2000, labView control QE-PRO spectrometer, keithley 2400, high-precision digital source table Keithley 6485, optical fiber with an inner diameter of 50 μm, device test probes and jigs, efficiency test systems built by various connecting wires and elements such as data cards, efficiency test cassettes and data acquisition systems), and parameters such as voltage, current, brightness, light emission spectrum, etc. of each light emitting device were obtained, and then key parameters such as maximum external quantum efficiency, power efficiency, etc. were calculated and the device lifetime of each light emitting device was tested by lifetime test devices.

The method for testing the current efficiency comprises intermittently collecting the brightness value of the light emitting device with the driving voltage ranging from 0V to 8V, wherein the collected light emitting area is 0.0314cm ², the voltage value of the initial collected brightness is 3V, the current efficiency of the light emitting device under the condition of the collection is obtained by dividing the brightness value collected every 0.2V by the corresponding current density, and the current efficiency (C.E@5000 nit, cd/A) under the condition of the collection is obtained.

The device life test method comprises the steps of carrying out electroluminescence life analysis on each light emitting device by adopting a 128-channel QLED life test system under the drive of constant current density (63.7 mA/cm ²), recording the time (T95, h) required for each light emitting device to decay from maximum brightness to 95%, and calculating the time (T95@1000nit, h) required for each light emitting device to decay from 100% to 95% under the brightness of 1000nit by a decay fitting formula.

In the performance detection process, three parallel samples are arranged for each light-emitting device, and each performance detection parameter takes the test average value of the three parallel samples. The results of performance measurements of each light emitting device in a 25 ℃ environment are shown in table 1 below:

table 1 list of performance test results of light emitting devices completed in examples 1 to 6 and comparative example

As can be seen from table 1, the overall performance of the light emitting devices of examples 1 to 6 has significant advantages over the light emitting devices of comparative examples, in that the light emitting devices of examples 1 to 6 are superior in both light emitting efficiency and device lifetime to the light emitting devices of comparative examples. Taking examples as an example, t95@1000nit of the light emitting device in example 1 is 1.73 times that of the light emitting device in comparative example, and c.e@5000nit of the light emitting device in example 1 is 1.31 times that of the light emitting device in comparative example.

Therefore, the auxiliary layer is arranged between the electronic functional layer and the light-emitting layer, the auxiliary layer comprises a connecting group, the connecting group is respectively connected with the electronic functional layer and the light-emitting layer, the connection tightness between the light-emitting layer and the electronic functional layer can be improved, the quantity of quantum dots in direct contact with ZnO is reduced, the oxygen vacancy defect of ZnO in one surface of the electronic functional layer, which is close to the light-emitting layer, is reduced, the fluorescence quenching effect of ZnO on the quantum dots is reduced, znO in the electronic functional layer still maintains the original lattice defect, and the good electron transmission performance is given to the electronic functional layer, and in addition, the connecting group contains carbon-carbon double bonds to provide high-density electron cloud, so that the electronic functional layer and the light-emitting layer have good charge transmission efficiency, and the electron cloud with high density can also block the injection of excessive electrons, so that the light-emitting device has good exciton recombination efficiency is ensured, and the light-emitting efficiency and the service life of the light-emitting device are improved.

The light emitting device, the preparation method of the light emitting device and the electronic equipment provided by the embodiment of the application are described in detail. While specific examples have been described herein for the purpose of illustrating the principles and embodiments of the present application, the above examples are provided for the purpose of aiding in the understanding of the technical solutions and their core ideas, and it should be understood by those skilled in the art that the technical solutions described in the foregoing examples may be modified or some of the technical features may be replaced equally, and these modifications or substitutions do not depart from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A light emitting device, comprising:

An anode and a cathode arranged opposite to each other;

A light-emitting layer is disposed between the anode and the cathode;

an electronic functional layer, disposed between the cathode and the light-emitting layer; and

An auxiliary layer, disposed between the electronic functional layer and the light-emitting layer;

Wherein, the auxiliary layer includes a connecting group, and the connecting group is a first group of the structure shown in the following general formula (I) and/or a second group of the structure shown in the following general formula (II):

Wherein, * represents a connecting bond; the connecting group is connected to the electronic functional layer and the light-emitting layer respectively;

R ₁ , R ₂ , R ₅ and R ₆ are independently selected from one or more of hydrogen, deuterium, tritium, substituted or unsubstituted C1-C10 straight-chain or branched hydrocarbon groups, substituted or unsubstituted C1-C10 straight-chain or branched hydrocarbon groups, substituted or unsubstituted aliphatic cycloalkyl groups having 3-30 ring atoms, substituted or unsubstituted aliphatic heterocycloalkyl groups having 3-30 ring atoms, substituted or unsubstituted aryl groups having 6-30 ring atoms, and substituted or unsubstituted heteroaryl groups having 5-30 ring atoms;

R ₃ , R ₄ , R ₇ and R ₈ are independently selected from -(CH ₂ ) _n - or -CH=CH-, and n is a positive integer of 1-6.

2. The light-emitting device according to claim 1, characterized in that the substituted or unsubstituted C1-C10 straight-chain hydrocarbon group or branched hydrocarbon group is selected from C1-C3 straight-chain hydrocarbon group or branched hydrocarbon group; and/or

The substituted or unsubstituted C1-C10 straight chain alkyloxy or branched chain alkyloxy is selected from C1-C3 straight chain alkyloxy or branched chain alkyloxy; and/or

The substituted or unsubstituted aliphatic cycloalkyl group having 3 to 30 ring atoms is selected from aliphatic cycloalkyl groups having 3 to 10 ring atoms; and/or

The substituted or unsubstituted aliphatic heterocyclic hydrocarbon group having 3 to 30 ring atoms is selected from aliphatic heterocyclic hydrocarbon groups having 3 to 10 ring atoms; and/or

The substituted or unsubstituted aryl group having 6 to 30 ring atoms is selected from aryl groups having 6 to 18 ring atoms; and/or

The substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms is selected from heteroaryl groups having 5 to 18 ring atoms.

3. The light-emitting device according to claim 1, characterized in that the connecting group is selected from one or more of the following groups:

4. The light-emitting device according to claim 1, characterized in that the material of the electronic functional layer comprises a first inorganic compound, the connecting group connects the first inorganic compound, and the first inorganic compound comprises one or more of an undoped first metal oxide, a doped second metal oxide, a II-VI semiconductor material, a III-V semiconductor material, and a I-III-VI semiconductor material;

Wherein, the non-doped first metal oxide is selected from one or more of ZnO, _TiO2 , _SnO2 , _BaO , _Ta2O3 , _Al2O3 _and _ZrO2 ; and/or, the doped second metal oxide is a main metal oxide doped with a first doping element, and the main metal oxide is selected from ZnO, _TiO2 , _SnO2 , _BaO , _Ta2O3 , _Al2O3 or _ZrO2 _. , the first doping element is selected from one or more of Mg, Ca, Zr, W, Ga, Li, Al, Ti, Y, In and Sn, and/or the molar percentage of the first doping element in the doped second metal oxide is less than 50%; and/or the II-VI group semiconductor material is selected from one or more of ZnS, ZnSe and CdS; and/or the III-V group semiconductor material is selected from one or more of InP and GaP; and/or the I-III-VI group semiconductor material is selected from one or more of CuInS and CuGaS; and/or

The material of the light-emitting layer comprises quantum dots, and the connecting group connects the quantum dots; the quantum dots are selected from one or more of single-component quantum dots, core-shell structure quantum dots, inorganic perovskite quantum dots, organic perovskite quantum dots and organic-inorganic hybrid perovskite quantum dots; the material of the single-component quantum dots, the material of the core of the core-shell structure quantum dots and the material of the shell of the core-shell structure quantum dots are independently selected from at least one of II-VI compounds, III-V compounds, IV-VI compounds or I-III-VI compounds, wherein the II-VI compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe , ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, and the III-V group compound is selected from one or more of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InNP , InNAs, InNSb, InPAs, InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNA s, InAlNSb, InAlPAs and InAlPSb, the IV-VI group compound is selected from one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe and SnPbSTe, and the I-III-VI group compound is selected from one or more of CuInS, CuInSe and AgInS; and/or the general structural formula of the inorganic perovskite quantum dot is AMX ₃ , wherein A is Cs ⁺ , M is a divalent metal cation, M is selected from one or more of Pb ²⁺ , Sn ²⁺ , Cu ²⁺ , Ni ²⁺ , Cd ²⁺ , Cr ²⁺ , Mn ²⁺ , Co ²⁺ , Fe ²⁺ , Ge ²⁺ , Yb ²⁺ and Eu ²⁺ , and X is a halogen anion; and/or, the general structural formula of the organic perovskite quantum dot is CMX ₃ , C is a carboxamidine group; and/or, the general structural formula of the organic-inorganic hybrid perovskite quantum dot is BMX ₃ , and B is an organic amine cation.

5. The light-emitting device according to claim 1, characterized in that the material of the anode and the material of the cathode independently contain one or more of a metal, a carbon material and a third metal oxide; wherein the metal is selected from one or more of Al, Ag, Cu, Mo, Au, Ba, Pt, Ca, Ir, Ni and Mg, and/or the carbon material is selected from one or more of graphite, carbon nanotubes, graphene and carbon fibers, and/or the third metal oxide is selected from one or more of indium-doped tin oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, indium-doped zinc oxide, magnesium-doped zinc oxide, aluminum-doped magnesium oxide, SnO ₂ , ZnO and In ₂ O ₃ ; and/or

The light-emitting device further comprises a hole functional layer, which is arranged between the anode and the light-emitting layer. The material of the hole functional layer comprises a non-doped second inorganic compound, a doped third inorganic compound, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonic acid), copper phthalocyanine, titanium phthalocyanine, 2,3,5,6-tetrafluoro-7,7',8,8'-tetracyanodimethyl-p-benzoquinone, 2,3,6,7,10,11-hexyano-1,4,5,8,9,12-hexaazatriphenylene, polypyrrole, polyaniline, 3-hexyl substituted polythiophene, poly(9-vinylcarbazole), 4,4'-bis(9-carbazole)biphenyl, poly[bis(4-phenyl)(4-butyl) phenyl)amine], 4,4'-cyclohexylbis[N,N-bis(4-methylphenyl)aniline], poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine)], poly[(N,N'-(4-n-butylphenyl)-N,N'-diphenyl-1,4-phenylenediamine)-ALT-(9,9-di-n-octylfluorenyl-2,7-diyl)], 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, 4,4',4"-tris(carbazol-9-yl)triphenylamine, 4,4',4'-tris(2-naphthylphenylamino)triphenylamine, N,N'-diphenyl-N,N'-(1- The following are some of the following: N,N'-diphenyl-N,N'-di(3-methylphenyl)-1,1'-biphenyl-4,4'-diamine, N,N'-bis[4-(diphenylamino)phenyl]-N,N'-diphenylbenzidine, N,N'-bis(3-methylphenyl)-N,N'-diphenyl-9,9-spirobifluorene-2,7-diamine, N2,N7-di-1-naphthyl-N2,N7-diphenyl-9,9'-spirobi[9H-fluorene]-2,7-diamine, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] and 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9, 9'-spirobifluorene; wherein the non-doped second inorganic compound is selected from one or more of graphene, C60, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, P-type gallium nitride, chromium oxide, copper oxide, copper sulfide, molybdenum sulfide and tungsten sulfide; and/or, the doped third inorganic compound is a main inorganic compound doped with a second doping element, the main inorganic compound is selected from one or more of graphene, C60, nickel oxide, molybdenum oxide, tungsten oxide, vanadium oxide, P-type gallium nitride, chromium oxide, copper oxide, copper sulfide, molybdenum sulfide and tungsten sulfide, and/or the second doping element is selected from one or more of nickel, molybdenum, tungsten, vanadium, chromium oxide, copper oxide, copper sulfide, molybdenum sulfide and tungsten sulfide, and/or the second doping element is selected from one or more of nickel, molybdenum, tungsten, vanadium, chromium, copper and platinum group metal elements.

6. A method for preparing a light emitting device, characterized in that it comprises the following steps:

providing a bottom electrode, and forming a light-emitting layer on one side of the bottom electrode; and

forming a top electrode on a side of the light-emitting layer away from the bottom electrode;

Wherein, when the light-emitting device is of a positive structure, the bottom electrode is an anode and the top electrode is a cathode, after the step of forming the light-emitting layer and before the step of forming the top electrode, the preparation method further comprises the steps of: depositing a solution containing an auxiliary functional material on a side of the light-emitting layer away from the bottom electrode so that at least part of the auxiliary functional material is connected to the light-emitting layer, and then forming an electronic functional layer on a side of the light-emitting layer where the solution is deposited, and an auxiliary layer is formed between the electronic functional layer and the light-emitting layer; or,

When the light-emitting device is an inverted structure, the bottom electrode is a cathode and the top electrode is an anode, and before the step of forming a light-emitting layer on one side of the bottom electrode, the preparation method further comprises the steps of: forming an electronic functional layer on one side of the bottom electrode, and then depositing a solution containing an auxiliary functional material on a side of the electronic functional layer away from the bottom electrode, so that at least part of the auxiliary functional material is connected to the electronic functional layer; after forming the light-emitting layer on the side of the electronic functional layer where the solution is deposited, an auxiliary layer is formed between the electronic functional layer and the light-emitting layer;

Wherein, the auxiliary functional material comprises a compound having a structure represented by the following general formula (III) and/or a compound having a structure represented by the following general formula (IV):

7. The preparation method according to claim 6, characterized in that the mass of the auxiliary functional material accounts for 3% to 5% of the total mass of the solution; and/or

The deposition thickness of the solution is 5nm to 10nm; and/or

The substituted or unsubstituted C1-C10 straight-chain or branched-chain hydrocarbon group is selected from C1-C3 straight-chain or branched-chain hydrocarbon groups; and/or

8. The preparation method according to claim 6, characterized in that the auxiliary functional material is selected from one or more of the following compounds:

9. The preparation method according to claim 6, characterized in that when the light-emitting device is a vertical structure, after the step of depositing a solution containing an auxiliary functional material on a side of the light-emitting layer away from the bottom electrode and before the step of forming the electronic functional layer, the preparation method further comprises the steps of: removing the auxiliary functional material not connected to the light-emitting layer;

Alternatively, when the light-emitting device is an inverted structure, after the step of depositing a solution containing auxiliary functional materials on a side of the electronic functional layer away from the bottom electrode and before the step of forming the light-emitting layer, the preparation method further includes the step of removing the auxiliary functional materials that are not connected to the electronic functional layer.

10. An electronic device, characterized in that it comprises the light-emitting device as claimed in any one of claims 1 to 5, or the light-emitting device manufactured by the manufacturing method as claimed in any one of claims 6 to 9.