Composite material and preparation method thereof, photoelectric device and display device

Abstract

The invention discloses a composite material and a preparation method thereof, a photoelectric device and a display device, and relates to the technical field of display. The composite material comprises inorganic nanoparticles and a ligand connected with the inorganic nanoparticles, the chemical formula of the ligand is X-L1-Ar-L2-COOH, and the structural formula of the ligand is as shown in the X is selected from halogen; ar is selected from a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a combination thereof. According to the composite material provided by the invention, the ligand can passivate surface defects of the inorganic nanoparticles, and the transmission efficiency of current carriers is improved.

Description

Technical Field

[0001] The present application relates to the field of display technologies, and in particular, to a composite material, a preparation method thereof, an optoelectronic device, and a display device. Background Art

[0002] Currently, the widely used optoelectronic devices are organic light-emitting diodes (OLEDs) and quantum dot light-emitting diodes (QLEDs). Due to its excellent display performance such as self-luminescence, simple structure, ultra-thin and light, fast response speed, wide viewing angle, low power consumption, and flexible display, OLED has become the mainstream technology in the field of display technology. QLED has the advantages of saturated emission light color and adjustable wavelength, and high photoluminescence and electroluminescence quantum yields. In recent years, it has become a strong competitor of OLED.

[0003] In the prior art, inorganic nanoparticles are often used as the material of the charge carrier functional layer to improve the charge carrier transport efficiency. However, the inorganic nanoparticles have surface defects, and the light emission efficiency of the device needs to be further improved. Summary of the Invention

[0004] In view of this, the present application provides a composite material, a preparation method thereof, an optoelectronic device, and a display device.

[0005] The embodiment of the present application is implemented as follows. A composite material includes inorganic nanoparticles and a ligand connected to the inorganic nanoparticles; the chemical formula of the ligand is X-L 1 -Ar-L 2 -COOH; wherein,

[0006] X is selected from halogen;

[0007] Ar is selected from a substituted or unsubstituted aryl group, a substituted or unsubstituted heteroaryl group, or a combination thereof, and the substituents of the substitution include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto group, and cyano group.

[0008] L 1 、L 2 are each independently selected from a single bond, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=N-, -N=CH-, -N=N-, a substituted or unsubstituted C 1 -C 12 alkylene group or a C 2 -C 12 alkenyl group, and at least one hydrogen atom in the C 1 -C 12 alkylene group or the C 2 -C 12 alkenyl group is replaced by -D, -F, -Cl, -Br, -I, -CN, -NO2 Substituted, C 2 -C 12 of the alkylene group or C 3 -C 12 in the alkenyl group of one -CH 2 - or at least two non - adjacent -CH 2 - is substituted by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C═C- in a non - directly connected manner to each other, and the substituents of the substitution include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto, cyano.

[0009] Accordingly, the embodiment of the present application further provides a preparation method of a composite material, including,

[0010] Providing a ligand, the chemical formula of the ligand is X - L 1 -Ar - L 2 -COOH; wherein, X is selected from halogen; Ar is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a combination thereof; L 1 , L 2 each independently is selected from a single bond, -O-, -S-, -CO-, -CO - O-, -O - CO-, -O - CO - O-, -CH═N-, -N═CH-, -N═N-, substituted or unsubstituted C 1 -C 12 of the alkylene group or C 2 -C 12 of the alkenyl group, at least one hydrogen atom in the C 1 -C 12 of the alkylene group or C 2 -C 12 of the alkenyl group is substituted by -D, -F, -Cl, -Br, -I, -CN, -NO 2 substituted, C 2 -C 12 of the alkylene group or C 3 -C 12 in the alkenyl group of one -CH 2 - or at least two non - adjacent -CH 2 - is substituted by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C═C- in a non - directly connected manner to each other;

[0011] Providing an inorganic nanoparticle dispersion liquid, the inorganic nanoparticle dispersion liquid includes inorganic nanoparticles, and mixing the ligand with the inorganic nanoparticle dispersion liquid to obtain a composite material.

[0012] Accordingly, an embodiment of the present application further provides an optoelectronic device, which includes an anode, a photoactive layer, an electron functional layer, and a cathode that are sequentially stacked; the material of the electron functional layer includes the above composite material, or includes the composite material prepared by the above preparation method.

[0013] Accordingly, an embodiment of the present application further provides a display device, and the display device includes the above optoelectronic device.

[0014] For the composite material provided by the present application, the ligand can passivate the surface defects of the inorganic nanoparticles, improve the carrier transport efficiency, and thus enhance the light emission efficiency of the optoelectronic device. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0016] Figure 1 It is a flowchart of the preparation method of the composite material provided by the embodiment of the present application;

[0017] Figure 2 It is a schematic structural diagram of the optoelectronic device provided by the embodiment of the present application.

[0018] Reference Signs:

[0019] Optoelectronic device 100; Anode 10; Photoactive layer 20; Electron functional layer 30; Cathode 40; Hole functional layer 50. Detailed Embodiments

[0020] The following will clearly and completely describe the technical solutions in the embodiments of the present application with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application. In addition, it should be understood that the specific embodiments described herein are only used to illustrate and explain the present application, and are not used to limit the present application.

[0021] In the present application, unless otherwise stated, the orientation terms such as "upper" and "lower" usually refer to the upper and lower in the actual use or working state of the device, specifically the drawing direction in the drawings; and "inner" and "outer" refer to the outline of the device. In addition, in the description of the present application, the term "comprising" means "including but not limited to". The terms first, second, third, etc. are only used as labels and do not impose numerical requirements or establish an order.

[0022] In this application, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, or B exists alone. Here, A and B can be singular or plural.

[0023] In this application, "at least one" means one or more, and "a plurality" means two or more. "One or several", "at least one of the following (item)" or similar expressions refer to any combination of these items, including any combination of single items or plural items. For example, "at least one of a, b, or c", or "at least one of a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.

[0024] The various embodiments of this application can exist in the form of a range; it should be understood that the description in the form of a range is only for convenience and brevity, and should not be construed as a rigid limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub - ranges and individual values within that range. For example, it should be considered that the range description 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., and individual numbers within that range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited number (fraction or integer) within the indicated range.

[0025] The technical solution of this application is as follows:

[0026] In a first aspect, an embodiment of this application provides a composite material, comprising inorganic nanoparticles and a ligand connected to the inorganic nanoparticles; the chemical formula of the ligand is X - L 1 -Ar - L 2 -COOH; wherein,

[0027] X is selected from halogens;

[0028] Ar is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a combination thereof, and the substituents of the substitution include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto group, and cyano group;

[0029] L 1 、L 2Each independently selected from a single bond, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=N-, -N=CH-, -N=N-, substituted or unsubstituted C 1 -C 12 alkylene or C 2 -C 12 alkenyl, at least one hydrogen atom in the C 1 -C 12 alkylene or C 2 -C 12 alkenyl is substituted by -D, -F, -Cl, -Br, -I, -CN, -NO 2 Substitution, C 2 -C 12 alkylene or C 3 -C 12 One -CH in alkenyl 2 - or at least two non-adjacent -CH 2 - is substituted by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C=C- in a non-directly connected manner to each other, and the substituted substituents include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto group, cyano group.

[0030] The composite material provided by the present application includes inorganic nanoparticles and ligands connected to the inorganic nanoparticles. The carboxyl groups and X halogens on the ligands can both be connected to the inorganic nanoparticles, thereby isolating the inorganic nanoparticles from each other, avoiding the aggregation of inorganic nanoparticles, and improving the physical stability of inorganic nanoparticles; after the ligands are connected to the inorganic nanoparticles, the surface defects of the inorganic nanoparticles can also be passivated, some trap energy levels can be eliminated, and the carrier transport performance of the inorganic nanoparticles can be improved; Ar can be used as an electron buffer to adjust the migration rate of carriers.

[0031] In some embodiments, the X is selected from F, Cl, Br, I.

[0032] In some embodiments, the Ar is selected from substituted or unsubstituted aryl groups with 6 to 18 ring atoms, substituted or unsubstituted heteroaryl groups with 5 to 25 ring atoms, or combinations thereof.

[0033] In some embodiments, the Ar includes phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, carbazolyl, benzocarbazolyl, triphenylamine group, thiophenyl, furyl, pyrrolyl, benzofuryl, benzothiophenyl, benzopyrrolyl, pyridyl, spirobifluorene group.

[0034] In some embodiments, the substituents in the substituted aryl of Ar and the substituents in the substituted heteroaryl are each independently selected from one or more of -F, -Cl, -Br, -CH 3 , -OCH 3 , -NO 2 , -ONHNH 2 , -NHNH 2 , -NH 2 .

[0035] In some embodiments, the heteroatoms in the heteroaryl include one or more of P, N, and S.

[0036] In some embodiments, the ligand includes 2-(4-bromomethylphenyl)propionic acid, p-fluorobenzoic acid, 4-chlorobenzoic acid, 4-bromobenzoic acid, p-iodobenzoic acid, 3-(4-fluorophenyl)propionic acid, 3-(4-chlorophenyl)propionic acid, 3-(4-bromophenyl)propionic acid, 3-(4-iodophenyl)propionic acid, 3-(3-chloro-4-methoxyphenyl)propionic acid, 5-(4-bromophenyl)-2-furoic acid, 3-(3-bromo-4-methylphenyl)propionic acid, 4-(4-bromophenyl)thiophene-2-carboxylic acid.

[0037] In some embodiments, the structural formula of the ligand is selected from one of the following formulas:

[0038]

[0039] In some embodiments, the inorganic nanoparticles contain a metal element, and the -X and / or -COOH of the ligand are connected to the metal element through a coordination bond.

[0040] In some embodiments, in the composite material, the molar ratio of the inorganic nanoparticles to the ligand is 1:(50 - 200), for example, it can be 1:80, 1:100, 1:120, 1:150, 1:180, etc. Within the range of the molar ratio, it is beneficial for the ligand to effectively passivate the defects of the inorganic nanoparticles.

[0041] In some embodiments, the average particle size of the inorganic nanoparticles is 3 nm to 20 nm, for example, it can be 5 nm, 8 nm, 10 nm, 12 nm, 15 nm, 18 nm, etc.

[0042] In some embodiments, the inorganic nanoparticles include one or more of first doped metal oxide particles, first undoped metal oxide particles, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The materials of the first undoped metal oxide particles include ZnO, TiO 2 , SnO 2, ZrO 2 , Ta 2 O 5 or one or more of the following, the metal oxides in the first doped metal oxide particles include ZnO, TiO 2 , SnO 2 , ZrO 2 , Ta 2 O 5 , Al 2 O 3 or one or more of the following, the doping elements in the first doped metal oxide particles include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, the IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, CdS, CdO, CdSe, the IIIA-VA group semiconductor materials include one or more of InP, GaP, AlP, InAs, GaAs, AlAs, and the IB-IIIA-VIA group semiconductor materials include one or more of CuInS, CuGaS, CuInSe, CuGaSe, AgInS, AgGaS, AgInSe, AgGaSe.

[0043] In a second aspect, please refer to Figure 1 , the embodiments of the present application further provide a preparation method of a composite material, including:

[0044] S11. Provide a ligand, the chemical formula of the ligand is X-L 1 -Ar-L 2 -COOH; wherein, X is selected from halogens; Ar is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a combination thereof; L 1 , L 2 are each independently selected from a single bond, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=N-, -N=CH-, -N=N-, substituted or unsubstituted C 1 -C 12 alkylene or C 2 -C 12 alkenyl, at least one hydrogen atom in the C 1 -C 12 alkylene or C 2 -C 12 alkenyl is substituted by -D, -F, -Cl, -Br, -I, -CN, -NO 2 , and one -CH in the C 2 -C 12 alkylene or C 3 -C 12 alkenyl2 - or at least two non - adjacent - CH 2 - are replaced by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C=C- in a non - directly - connected - to - each - other manner;

[0045] S12. Provide an inorganic nanoparticle dispersion liquid, which includes inorganic nanoparticles, and mix the ligand with the inorganic nanoparticle dispersion liquid to obtain a composite material.

[0046] In S12:

[0047] In some embodiments, the inorganic nanoparticle dispersion liquid further includes a first solvent.

[0048] In some embodiments, in the inorganic nanoparticle dispersion liquid, the mass concentration of the inorganic nanoparticles is 10 mg / mL to 50 mg / mL, for example, it can be 15 mg / mL, 20 mg / mL, 25 mg / mL, 30 mg / mL, 35 mg / mL, 40 mg / mL, 45 mg / mL, etc. Within the range of the mass concentration, it is beneficial for the inorganic nanoparticles to be fully dispersed and dissolved.

[0049] In some embodiments, the preparation method of the inorganic nanoparticles includes: providing a metal salt, a base, and a second solvent, mixing them to obtain inorganic nanoparticles.

[0050] In some embodiments, the metal salt includes one or more of zinc salt, titanium salt, tin salt, tantalum salt, zirconium salt, cadmium salt, copper salt, indium salt, gallium salt, aluminum salt, magnesium salt, lithium salt, yttrium salt, lanthanum salt, cerium salt.

[0051] In some embodiments, the metal salt includes one or more of acetate, sulfate, halide salt, nitrate. Exemplarily, the zinc salt includes one or more of zinc acetate, zinc sulfate, zinc halide, zinc nitrate.

[0052] In some embodiments, the base includes one or more of potassium hydroxide, lithium hydroxide, sodium hydroxide, ammonium hydroxide, ethylenediamine, ethanolamine, diethanolamine, triethanolamine, tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, tetrabutylammonium hydroxide.

[0053] In some embodiments, the molar ratio of the salt ions in the metal salt to the hydroxide ions in the base is 1:(1.5 - 3), for example, it can be 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.8, etc.

[0054] In some embodiments, the pH of the mixed solution after mixing the metal salt and the base is 12 to 14, and can be, for example, 12.2, 12.5, 12.8, 13, 13.2, 13.5, 13.8, etc.

[0055] In some embodiments, the method of mixing the metal salt, the base and the second solvent includes:

[0056] S121. Provide a metal salt solution and a base solution, where the metal salt solution includes a metal salt and a third solvent, and the base solution includes a base and a fourth solvent;

[0057] S122. Mix the metal salt solution and the base solution.

[0058] In S121:

[0059] In some embodiments, in the metal salt solution, the molar concentration of the metal salt solution is 0.1 mol / L to 1 mol / L, and can be, for example, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, etc. Within the range of the molar concentration, it is beneficial for the metal salt to be fully dissolved.

[0060] In some embodiments, in the base solution, the molar concentration of the base is 0.1 mol / L to 1 mol / L, and can be, for example, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L, 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, etc. Within the range of the molar concentration, it is beneficial for the base to be fully dissolved.

[0061] In some embodiments, the first solvent, the second solvent, the third solvent, and the fourth solvent each independently include one or more of chlorobenzene, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0062] In S122:

[0063] In some embodiments, the method of mixing the metal salt solution and the base solution includes: dropping the base solution into the metal salt solution. It can be understood that by using the dropping method for mixing, it is beneficial to control the pH within an appropriate range.

[0064] The mixing of the metal salt solution and the base solution can be carried out at room temperature.

[0065] In some embodiments, after mixing the metal salt solution and the alkali solution, first stirring is further included.

[0066] Furthermore, the time of the first stirring is 1 h to 4 h, and for example, it can be 1.5 h, 2 h, 2.5 h, 3 h, 3.5 h, etc. In this way, it is beneficial to fully mix the metal salt and the alkali to prepare inorganic nanoparticles.

[0067] In some embodiments, the molar ratio of the inorganic nanoparticles to the ligand is 1:(60 - 240), and for example, it can be 1:80, 1:100, 1:120, 1:150, 1:180, 1:200, 1:220, etc. Within the range of the molar ratio, it is beneficial for the ligand to passivate the defects of the inorganic nanoparticles and improve the carrier migration rate of the inorganic nanoparticles.

[0068] In some embodiments, the mixing time of the ligand and the inorganic nanoparticles is 10 min to 60 min, and for example, it can be 15 min, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min, etc.; the mixing temperature is 20 °C to 50 °C, and for example, it can be 22 °C, 25 °C, 28 °C, 30 °C, 32 °C, 35 °C, 38 °C, 40 °C, 42 °C, 45 °C, 48 °C, etc. Under the mixing conditions, it is beneficial for the inorganic nanoparticles and the ligand to fully react to achieve the coordination connection between the ligand and the inorganic nanoparticles.

[0069] In some embodiments, after the ligand reacts with the inorganic nanoparticle dispersion, a precipitating agent is further added to precipitate the composite material.

[0070] In some embodiments, the precipitating agent includes one or more of ethyl acetate, acetone, hexane, and heptane.

[0071] The preparation method of the composite material provided by this application is simple in operation and low in cost, and can effectively prepare a composite material with a ligand connected to inorganic nanoparticles.

[0072] In the third aspect, please refer to Figure 2 , this application embodiment also provides an optoelectronic device, including an anode 10, a photoactive layer 20, an electron functional layer 30, and a cathode 40 that are sequentially stacked; the material of the electron functional layer 30 includes the above composite material, or includes the composite material prepared by the above preparation method.

[0073] In the optoelectronic device provided by the present application, the material of the electronic functional layer 30 includes inorganic nanoparticles and ligands connected to the inorganic nanoparticles. One end of the ligand is connected to the inorganic nanoparticles, and the other end can be connected to the metal atoms in the photoactive layer 20, thereby improving the interfacial contact between the electronic functional layer 30 and the photoactive layer 20, and further enhancing the electron migration efficiency of the electronic functional layer 30. Moreover, the ligand can passivate the defects of the inorganic nanoparticles, eliminate some trap energy levels, and reduce the exciton quenching caused by the defect energy levels of the inorganic nanoparticles. The benzene ring in the ligand can further promote the electron migration rate between the electronic functional layer 30 and the photoactive layer 20, thereby improving the luminous efficiency and stability of the optoelectronic device.

[0074] It can be understood that in the optoelectronic device, the ligand can be connected to two inorganic nanoparticles at both ends respectively, or one end can be connected to the inorganic nanoparticles and the other end can be connected to the material of the photoactive layer 20.

[0075] In some embodiments, the optoelectronic device includes a light-emitting diode.

[0076] In some embodiments, the optoelectronic device further includes a hole functional layer 50, and the hole functional layer 50 is disposed between the anode 10 and the photoactive layer 20.

[0077] Furthermore, the hole functional layer 50 includes one or more of a hole injection layer and a hole transport layer.

[0078] The electronic functional layer 30 includes one or more of an electron injection layer and an electron transport layer.

[0079] In some embodiments, the anode 10 and the cathode 40 each independently include one or more of a metal, a carbon material, and a metal oxide; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg; the carbon material includes one or more of graphite, carbon nanotubes, graphene, and carbon fibers; the metal oxide includes a metal oxide electrode or a composite electrode with a metal sandwiched between doped or undoped transparent metal oxides. The material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO 3 and AMO, and the composite electrode includes AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO 2 / Ag / TiO 2 and TiO 2 / Al / TiO 2One or more of them. Herein, " / " represents a stacked structure. For example, AZO / Ag / AZO represents a composite electrode including an AZO layer, an Ag layer, and an AZO layer stacked in sequence.

[0080] In some embodiments, the material of the photoactive layer 20 includes one or more of an organic light-emitting material or a quantum dot light-emitting material.

[0081] The organic light-emitting material may be selected from, but not limited to, CBP:Ir(mppy) 3 (4,4'-bis(N-carbazolyl)-1,1'-biphenyl: tris[2-(p-tolyl)pyridine iridium(III)]), TCTX:Ir(mmpy) (4,4',4”-tris(carbazol-9-yl)triphenylamine: tris[2-(p-tolyl)pyridine iridium]), a diaryl anthracene derivative, a stilbene aromatic derivative, a pyrene derivative, a fluorene derivative, a TBPe fluorescent material, a TTPX fluorescent material, a TBRb fluorescent material, a DBP fluorescent material, a delayed fluorescence material, a TTA material, a TADF (thermally activated delayed) material, a polymer containing a B-N covalent bond, an HLCT (hybrid local charge transfer excited state) material, an Exciplex (exciplex) light-emitting material, or one or more of them.

[0082] The quantum dot light-emitting material may be selected from, but not limited to, one or more of a single structure quantum dot, a core-shell structure quantum dot, and a perovskite semiconductor material.

[0083] The materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots can be respectively selected from, but not limited to, one or several of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds. The shell of the core-shell structure quantum dots includes one or more layers; the II-VI group compounds can be selected from, but not limited to, one or several 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 IV-VI group compounds can be selected from, but not limited to, one or several of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V group compounds can be selected from, but not limited to, one or several 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 I-III-VI group compounds can be selected from, but not limited to, one or several of CuInS 2 , CuInSe 2 , and AgInS 2 .

[0084] As an example, the quantum dots of the core-shell structure can be selected from but not limited to one or several of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS. In the expressions such as CdSe / ZnS above, " / " means that the material after " / " (as the shell layer) coats the material before " / " (as the core layer).

[0085] The general structural formula of the perovskite semiconductor material is AMY 3 , where A is Cs + , CH 3 (CH 2 ) n-2 NH 3 + or [NH 3 (CH 2 ) n NH 3 2+ , where n≥2, M is selected from one or several of Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ , and Y is selected from one or several of Cl - , Br - , I - .

[0086] ​In some embodiments, the materials of the hole functional layer 50 include 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green light-emitting material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexoxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS doped with s-MoO 3 derivatives, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides and metal nitrides, one or several of them, the metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles independently include MoO 3 、WO 3 、NiO、CrO 3 、CuO、V 2 O 5 one or several of them, the doping elements in the second doped metal oxide particles include one or several of Mo, W, Ni, Cr, Cu, V, and the metal sulfides include CuS, MoS3 , WS 3 one or more of the following, and the metal selenide includes MoSe 3 , WSe 3 one or more of the following, and the metal nitride includes p-type gallium nitride.

[0087] Fourthly, an embodiment of the present application further provides a display device, and the display device includes the above optoelectronic device.

[0088] The display device may be any electronic product with a display function, and the electronic product includes but is not limited to a smart phone, a tablet computer, a notebook computer, a digital camera, a digital video camera, a smart wearable device, a smart weighing electronic scale, a vehicle-mounted display, a television or an e-book reader. Among them, the smart wearable device may be, for example, a smart bracelet, a smart watch, a virtual reality (VR) helmet, etc.

[0089] The present application will be specifically described below through specific embodiments. The following embodiments are only partial embodiments of the present application and do not limit the present application.

[0090] Embodiment 1

[0091] This embodiment provides a composite material, including zinc oxide and a 2-(4-bromomethylphenyl)propionic acid ligand connected to the zinc oxide, and the molar ratio of the zinc oxide to the ligand is 1:100; the preparation method is as follows:

[0092] Add 1 mmol of zinc acetate to DMF to form a metal salt solution with a concentration of 0.5 mol / L. Dropwise add an ethanol solution of 0.5 mol / L KOH at room temperature. After stirring for 1 h, a clear and transparent solution is obtained; precipitate ZnO inorganic nanoparticles with ethyl acetate, collect by centrifugation, and then dissolve and disperse with an appropriate amount of ethanol to obtain a ZnO dispersion; add 150 mmol of 2-(4-bromomethylphenyl)propionic acid ligand, stir at 30 °C for 30 min, and filter with a 0.2 μm filter head to obtain the composite material.

[0093] Embodiment 2

[0094] This embodiment is basically the same as Embodiment 1, except that the dosage of the ligand in this embodiment is 60 mmol, and the molar ratio of zinc oxide to 2-(4-bromomethylphenyl)propionic acid ligand in the composite material is 1:50.

[0095] Embodiment 3

[0096] This embodiment is basically the same as Embodiment 1, except that the dosage of the ligand in this embodiment is 240 mmol, and the molar ratio of zinc oxide to 2-(4-bromomethylphenyl)propionic acid ligand in the composite material is 1:200.

[0097] Example 4

[0098] This example is basically the same as Example 1, except that after adding the 2-(4-bromomethylphenyl)propionic acid ligand in this example, the stirring time is 60 min.

[0099] Example 5

[0100] This example is basically the same as Example 1, except that after adding the 2-(4-bromomethylphenyl)propionic acid ligand in this example, the stirring time is 10 min.

[0101] Example 6

[0102] This example is basically the same as Example 1, except that after adding the 2-(4-bromomethylphenyl)propionic acid ligand in this example, the stirring temperature is 50 °C.

[0103] Example 7

[0104] This example is basically the same as Example 1, except that after adding the 2-(4-bromomethylphenyl)propionic acid ligand in this example, the stirring temperature is 20 °C.

[0105] Example 8

[0106] This example is basically the same as Example 1, except that in this example, zinc acetate is replaced with titanium nitrate, and the composite material includes titanium oxide and the 2-(4-bromomethylphenyl)propionic acid ligand connected to the titanium oxide.

[0107] Example 9

[0108] This example is basically the same as Example 1, except that in this example, the 2-(4-bromomethylphenyl)propionic acid ligand is replaced with the 4-(4-bromophenyl)thiophene-2-carboxylic acid ligand.

[0109] Example 10

[0110] This example is basically the same as Example 1, except that in this example, the 2-(4-bromomethylphenyl)propionic acid ligand is replaced with the 3-(3-chloro-4-methoxyphenyl)propionic acid ligand.

[0111] Comparative Example 1

[0112] This comparative example provides a material including zinc oxide inorganic nanoparticles.

[0113] Comparative Example 2

[0114] This comparative example provides a composite material including zinc oxide inorganic nanoparticles and the tribromoacetic acid ligand connected to the zinc oxide inorganic nanoparticles.

[0115] Device Example 1

[0116] This example provides an optoelectronic device, and the preparation method is as follows:

[0117] Clean the ITO conductive glass with a cleaner to initially remove the stains on the surface. Subsequently, ultrasonically clean it in deionized water, acetone, absolute ethanol, and deionized water for 20 minutes respectively to remove the impurities on the surface. Finally, dry it with high-purity nitrogen to form the ITO anode;

[0118] Dissolve TFB in chlorobenzene at a concentration of 8 mg / mL. Spin-coat it on the ITO anode at a rotation speed of 3000 rpm for 30 s, and heat it at 150 °C for 30 min to form a 30-nm hole transport layer;

[0119] Prepare a quantum dot solution of CdZnSe with a mass concentration of 10 mg / mL. Spin-coat it on the hole transport layer at a rotation speed of 3000 rpm for 30 s, and heat it at 80 °C for 30 min to form a 40-nm light-emitting layer;

[0120] Dissolve the composite material prepared in Example 1 in ethanol. Spin-coat it on the light-emitting layer at a rotation speed of 4000 rpm for 30 s, and then heat it at 80 °C for 30 min to form a 40-nm electron transport layer;

[0121] On the electron transport layer, evaporate and deposit Ag by thermal evaporation. The vacuum degree is not higher than 3x10 -4 Pa, the speed is 1 Å / s, the time is 1000 s, and the thickness is 100 nm to form the cathode;

[0122] Encapsulate to obtain the optoelectronic device.

[0123] Device Examples 2 to 10

[0124] Device Examples 2 to 6 are basically the same as Device Example 1, except that in Device Examples 2 to 10, the composite material of Example 1 is replaced with the composite materials of Examples 2 to 10 respectively.

[0125] Device Comparative Examples 1 to 2

[0126] Device Comparative Examples 1 to 2 are basically the same as Device Example 1, except that in this device example, the composite material of Example 1 is replaced with the materials of Comparative Examples 1 to 2.

[0127] Measure the electron mobility of the electron transport layers, the luminous intensity of the optoelectronic devices, and the lifetime T95@1000 nit of Device Examples 1 to 10 and Device Comparative Examples 1 to 2 respectively. The results are shown in Table 1.

[0128] Among them, the test method for electron mobility is as follows: measure the current density-voltage curve of the half-device (single-carrier transport thin-film device HOD / EOD) of the optoelectronic device. Among them, the structure of EOD is anode / quantum dot light-emitting layer / electron transport layer / cathode, and the structure of HOD is anode / hole transport thin film / quantum dot light-emitting layer / cathode. Obtain the space charge limited current (SCLC) region in the current density-voltage curve, and then calculate the electron mobility according to the formula J=(9 / 8)ε r ε 0 μ e V 2 / d 3 where J represents the current density, with the unit of mAcm -2 ; ε r represents the relative permittivity, and ε 0 represents the vacuum permittivity; μ e represents the electron mobility, with the unit of cm 2 V -1 s -1 ; V represents the driving voltage, with the unit of V; d represents the film thickness, with the unit of m.

[0129] The physical meaning of luminous intensity is the luminous intensity passing through a unit area per unit time in a specific direction, with the unit of cd / A, and it is measured using a photometer.

[0130] The test method for the lifetime T95@1000nit is as follows: when the device is driven by a constant current or voltage, the time required for the brightness to decrease to a certain proportion of the maximum brightness. The time when the brightness drops to 95% of the maximum brightness is defined as T95, and this lifetime is the measured lifetime. To shorten the test cycle, the device lifetime test is usually carried out by accelerating the device aging at high brightness and obtaining the lifetime at high brightness through fitting with the extended exponential decay brightness decay fitting formula. For example, the lifetime at 1000nit is denoted as T95@1000nit. The specific calculation formula is as follows:

[0131]

[0132] where T95L is the lifetime at low brightness, T95H is the measured lifetime at high brightness, LH is the device accelerated to the maximum brightness, LL is 1000nit, and A is the acceleration factor. In this experiment, the value of A is obtained as 1.7 by measuring the lifetimes of several groups of green QLED devices at the rated brightness.

[0133] Table 1

[0134]

[0135]

[0136] As can be seen from Table 1:

[0137] It can be obtained from Examples 1 to 3 and Comparative Example 1 that within the range of the molar ratio of the inorganic nanoparticles to the ligand provided in the present application, the ligand can effectively passivate the defects of the inorganic nanoparticles, improve the electron mobility of the electron transport layer, promote the recombination of electrons and holes, thereby enhancing the luminescence intensity of the optoelectronic device. The carboxyl group and -Br on the ligand can also be connected to CdZnSe, and then the interface between the electron transport layer and the light-emitting layer can be adjusted, and the service life of the optoelectronic device can be extended;

[0138] It can be obtained from Examples 1, 4 to 7 and Comparative Example 1 that the reaction time and temperature of the ligand and the inorganic nanoparticles have a certain influence on the composite material of the inorganic nanoparticles and the ligand. Among them, due to the mild reaction temperature, the influence degree of the temperature on the composite material is less than that of the reaction time; the longer the reaction time, the closer the connection between the ligand and the inorganic nanoparticles, which is more conducive to improving the performance of the composite material, and then improving the electron mobility of the electron transport layer in the optoelectronic device, enhancing the luminescence intensity of the optoelectronic device, and extending the service life of the optoelectronic device;

[0139] It can be obtained from Examples 1, 8 to 10 and Comparative Example 2 that Examples 8 to 10 replace the material of the inorganic nanoparticles or the ligand material, and the performance of the optoelectronic device is still effectively improved. The effect of zinc oxide inorganic nanoparticles is better than that of titanium oxide inorganic nanoparticles, which is determined by the performance of the inorganic nanoparticle material itself; although the ligand in Comparative Example 2 contains -Br and carboxyl groups, it does not contain phenyl groups and cannot effectively adjust the electron migration rate from the electron transport layer to the light-emitting layer, so its effect is worse than that of the ligand provided in the present application.

[0140] The composite material, its preparation method, optoelectronic device, and display device provided in the embodiments of the present application have been introduced in detail above. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A composite material, characterized in that, comprising inorganic nanoparticles and a ligand linked to the inorganic nanoparticles; the chemical formula of the ligand is X-L 1 -Ar-L 2 -COOH; wherein, X is selected from halogens; Ar is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a combination thereof, and the substituents of the substitution include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto group, cyano group; L 1 and L 2 each independently selected from a single bond, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=N-, -N=CH-, -N=N-, a substituted or unsubstituted C 1 -C 12 alkylene or C 2 -C 12 alkenyl, wherein at least one hydrogen atom in the C 1 -C 12 alkylene or C 2 -C 12 alkenyl is substituted by -D, -F, -Cl, -Br, -I, -CN, -NO 2 , and one -CH 2 - or at least two non-adjacent -CH 12 - in the C 3 -C 12 alkylene or C 2 -C 2 alkenyl are substituted by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C=C- in a non-directly connected manner to each other, and the substituents of the substitution include amino, halogen, hydroxyl, carboxyl, nitro, sulfonic acid group, aldehyde group, mercapto, cyano.

2. The composite material according to claim 1, characterized in that, the X is selected from F, Cl, Br, I; and / or the Ar is selected from substituted or unsubstituted aryl with 6-18 ring atoms, substituted or unsubstituted heteroaryl with 5-25 ring atoms, or a combination thereof; and / or the Ar includes phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, carbazolyl, benzocarbazolyl, triphenylamine group, thiophenyl, furyl, pyrrolyl, benzofuryl, benzothiophenyl, benzopyrrolyl, pyridyl, spirobifluorene; and / or The substituents in the substituted aryl of Ar and the substituents in the substituted heteroaryl each independently include -F, -Cl, -Br, -CH 3 , -OCH 3 , -NO 2 , -ONHNH 2 , -NHNH 2 , -NH 2 one or more of; and / or the heteroatoms in the heteroaryl include one or more of O, P, N, S.

3. The composite material according to claim 1, characterized in that, the ligand includes 2-(4-bromomethylphenyl)propionic acid, p-fluorobenzoic acid, 4-chlorobenzoic acid, 4-bromobenzoic acid, p-iodobenzoic acid, 3-(4-fluorophenyl)propionic acid, 3-(4-chlorophenyl)propionic acid, 3-(4-bromophenyl)propionic acid, 3-(4-iodophenyl)propionic acid, 3-(3-chloro-4-methoxyphenyl)propionic acid, 5-(4-bromophenyl)-2-furoic acid, 3-(3-bromo-4-methylphenyl)propionic acid, 4-(4-bromophenyl)thiophene-2-carboxylic acid.

4. The composite material according to claim 1, characterized in that, in the composite material, the molar ratio of the inorganic nanoparticles to the ligand is 1:(50-200); and / or the average particle size of the inorganic nanoparticles is 3 nm - 20 nm; and / or the inorganic nanoparticles contain a metal element, and the -X and / or -COOH of the ligand are connected to the metal element through a coordination bond; and / or The inorganic nanoparticles include one or more of first doped metal oxide particles, first undoped metal oxide particles, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The materials of the first undoped metal oxide particles include one or more of ZnO, TiO 2 , SnO 2 , ZrO 2 , Ta 2 O 5 One or more of the above. The metal oxides in the first doped metal oxide particles include one or more of ZnO, TiO 2 , SnO 2 , ZrO 2 , Ta 2 O 5 , Al 2 O 3 One or more of the above. The doping elements in the first doped metal oxide particles include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, CdS, CdO, CdSe. The IIIA-VA group semiconductor materials include one or more of InP, GaP, AlP, InAs, GaAs, AlAs. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS, CuGaS, CuInSe, CuGaSe, AgInS, AgGaS, AgInSe, AgGaSe.

5. A preparation method of a composite material, characterized in that, comprising, Provide a ligand, the chemical formula of the ligand being X-L 1 -Ar-L 2 -COOH; wherein, X is selected from halogens; Ar is selected from substituted or unsubstituted aryl, substituted or unsubstituted heteroaryl, or a combination thereof; L 1 、L 2 are each independently selected from a single bond, -O-, -S-, -CO-, -CO-O-, -O-CO-, -O-CO-O-, -CH=N-, -N=CH-, -N=N-, substituted or unsubstituted C 1 -C 12 alkylene or C 2 -C 12 alkenyl, at least one hydrogen atom in the C 1 -C 12 alkylene or C 2 -C 12 alkenyl is substituted by -D, -F, -Cl, -Br, -I, -CN, -NO 2 , one -CH 2 - or at least two non-adjacent -CH 12 - in the C 3 -C 12 alkylene or C 2 -C 2 - in the alkenyl is substituted by -O-, -S-, -NH-, -CO-, COO-, -OCO-, -OCOO-, -SCO-, -COS- or -C=C- in a non-directly connected manner to each other; providing an inorganic nanoparticle dispersion liquid, which includes inorganic nanoparticles, and mixing the ligand with the inorganic nanoparticle dispersion liquid to obtain a composite material.

6. The preparation method according to claim 5, characterized in that, the X is selected from F, Cl, Br, I; and / or the Ar is selected from substituted or unsubstituted aryl with 6-18 ring atoms, substituted or unsubstituted heteroaryl with 5-25 ring atoms, or a combination thereof; and / or the Ar includes phenyl, biphenyl, terphenyl, naphthyl, anthracenyl, phenanthryl, carbazolyl, benzocarbazolyl, triphenylamine group, thiophenyl, furyl, pyrrolyl, benzofuryl, benzothiophenyl, benzopyrrolyl, pyridyl, spirobifluorene; and / or The substituents in the substituted aryl of Ar and the substituents in the substituted heteroaryl each independently include one or more of -F, -Cl, -Br, -CH 3 , -OCH 3 , -NO 2 , -ONHNH 2 , -NHNH 2 , -NH 2 ; and / or the heteroatoms in the heteroaryl include one or more of O, P, N, S.

7. The preparation method according to claim 5, characterized in that, The ligands include 2-(4-bromomethylphenyl)propionic acid, p-fluorobenzoic acid, 4-chlorobenzoic acid, 4-bromobenzoic acid, p-iodobenzoic acid, 3-(4-fluorophenyl)propionic acid, 3-(4-chlorophenyl)propionic acid, 3-(4-bromophenyl)propionic acid, 3-(4-iodophenyl)propionic acid, 3-(3-chloro-4-methoxyphenyl)propionic acid, 5-(4-bromophenyl)-2-furoic acid, 3-(3-bromo-4-methylphenyl)propionic acid, 4-(4-bromophenyl)thiophene-2-carboxylic acid.

8. The preparation method according to claim 5, characterized in that the molar ratio of the inorganic nanoparticles to the ligand is 1:(60-240); and / or in the inorganic nanoparticle dispersion, the mass concentration of the inorganic nanoparticles is 10 mg / mL to 50 mg / mL; and / or the mixing time of the ligand and the inorganic nanoparticles is 10 min to 60 min; the mixing temperature is 20°C to 50°C; and / or the inorganic nanoparticle dispersion further includes a first solvent; the first solvent includes one or more of chlorobenzene, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

9. An optoelectronic device, characterized in that it includes an anode, a photoactive layer, an electron functional layer, and a cathode that are sequentially stacked; the material of the electron functional layer includes the composite material according to any one of claims 1 to 4, or includes the composite material prepared by the preparation method according to any one of claims 5 to 8.

10. The optoelectronic device according to claim 9, characterized in that The anode and the cathode each independently include one or more of a metal, a carbon material, and a metal oxide; the metal includes one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg; the carbon material includes one or more of graphite, carbon nanotubes, graphene, and carbon fibers; the metal oxide includes a metal oxide electrode or a composite electrode in which a doped or undoped transparent metal oxide sandwiches a metal, and the material of the metal oxide electrode includes one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO 3 and one or more of AMO, and the composite electrode includes one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO 2 / Ag / TiO 2 and TiO 2 / Al / TiO 2 and / or The materials of the photoactive layer include organic light-emitting materials or quantum dot light-emitting materials; the organic light-emitting materials include one or more of 4,4'-bis(N-carbazolyl)-1,1'-biphenyl: tris[2-(p-tolyl)pyridineiridium(III)], 4,4',4”-tris(carbazol-9-yl)triphenylamine: tris[2-(p-tolyl)pyridineiridium], diarylanthracene derivatives, stilbene aromatic derivatives, pyrene derivatives, fluorene derivatives, TBPe fluorescent materials, TTPX fluorescent materials, TBRb fluorescent materials, DBP fluorescent materials, delayed fluorescence materials, TTA materials, TADF materials, polymers containing B-N covalent bonds, HLCT materials, Exciplex light-emitting materials; the quantum dot light-emitting materials include one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite semiconductor materials. The materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots are each independently selected from one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the shell of the core-shell structure quantum dots includes one or more layers; the II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, 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 IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe;The III-V compound includes 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 I-III-VI compound includes one or more of CuInS 2 , CuInSe 2 and AgInS 2 ; the structural general formula of the perovskite semiconductor material is AMY 3 , where A is Cs + , CH 3 (CH 2 ) n-2 NH 3 + or [NH 3 (CH 2 ) n NH 3 2+ , where n≥2, 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+ , Eu 2+ ; Y is selected from one or more of Cl - , Br - , I - ; and / or​ The optoelectronic device further includes a hole functional layer disposed between the anode and the photoactive layer; the material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green luminescent material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS doped with s-MoO 3 derivatives, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose and tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides and metal nitrides, one or more of which, the metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles independently include MoO 3 、WO 3 、NiO、CrO 3 、CuO、V 2 O 5 One or more of the following, the doping elements in the second doped metal oxide particles include one or more of Mo, W, Ni, Cr, Cu, V, and the metal sulfide includes CuS, MoS 3 , WS 3 One or more of the following, the metal selenide includes MoSe 3 , WSe 3 , CuSe 3 One or more of the following, and the metal nitride includes p-type gallium nitride.

11. A display device, characterized in that it includes the optoelectronic device according to any one of claims 9 to 10.

Images