WO2024139692A1

WO2024139692A1 - Light-emitting apparatus and manufacturing method therefor, and display device

Info

Publication number: WO2024139692A1
Application number: PCT/CN2023/128816
Authority: WO
Inventors: 侯文军
Original assignee: Tcl科技集团股份有限公司
Priority date: 2022-12-30
Filing date: 2023-10-31
Publication date: 2024-07-04
Also published as: CN118284106A

Abstract

Provided in the present application are a light-emitting apparatus and a manufacturing method therefor, and a display device. An electronic functional layer of the light-emitting apparatus comprises metal oxide nanoparticles and a polymer, wherein the polymer comprises one or more of a supramolecular compound that is obtained by reacting a fatty acid with a nitrogen-containing compound, a polyurethane containing ureido pyrimidinone, a polyamide containing ureido pyrimidinone and a polyacrylamide containing ureido pyrimidinone. When cracks appear in a thin film of the electronic functional layer, the polymer can repair the cracks.

Description

Light emitting device, method for manufacturing the same, and display device

This application claims priority to the Chinese patent application filed with the China Patent Office on December 30, 2022, with application number 202211736046.0 and application name “Light-emitting device, manufacturing method thereof and display device”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of quantum dot luminescence technology, and in particular to a light-emitting device, a manufacturing method thereof, and a display device.

Background technique

Due to the unique optoelectronic properties of quantum dots, such as the continuously adjustable emission wavelength with size and composition, narrow emission spectrum, high fluorescence efficiency, and good stability, quantum dot-based electroluminescent diodes (QLED) have received extensive attention and research in the display field. In addition, QLED display also has many advantages that LCD cannot achieve, such as large viewing angle, high contrast, fast response speed, and flexibility, so it is expected to become the next generation of display technology.

When QLED devices work, they need to inject electrons and holes. Simple QLED devices are composed of cathode, electron transport layer, quantum dot layer, hole transport layer and anode. In QLED devices, quantum dot film is sandwiched between charge transport layer. When forward bias is applied to both ends of QLED devices, electrons and holes enter quantum dot light-emitting layer through electron transport layer and hole transport layer respectively, and then recombine and emit light in quantum dot light-emitting layer.

However, since the electronic functional layer of the QLED device contains metal oxide nanoparticles, when the QLED device is subjected to external pressure, these metal oxide nanoparticles can easily cause cracks in the electronic functional layer, thereby hindering carrier transmission and reducing luminous efficiency and device life.

Technical Solutions

In view of this, the present application provides a QLED device including an electronic functional layer with a self-repairing function to ensure the luminous efficiency and device life.

The present application provides a light-emitting device, which comprises a first electrode and a second electrode arranged opposite to each other, a light-emitting layer arranged between the first electrode and the second electrode; and an electronic functional layer arranged between the second electrode and the light-emitting layer; wherein the electronic functional layer comprises metal oxide nanoparticles and a polymer, and the polymer comprises a supramolecular compound reacted by a fatty acid and a nitrogen-containing compound, a polyurethane containing ureido pyrimidone, a polyamide containing ureido pyrimidone, and a One or more of the polyacrylamides of pyrimidone.

Optionally, in some embodiments, the ureidopyrimidone-containing polyurethane comprises polyurethane side chain grafted 2-urea-4[1H]-pyrimidone.

Optionally, in some embodiments, in the supramolecular compound formed by the reaction of the fatty acid and the nitrogen-containing compound, the fatty acid is selected from oxalic acid, malonic acid, 1,7-heptanedioic acid, octadecanedioic acid, triacylglycerol, 2-hydroxybutanetriolic acid, citric acid, and oxalosuccinic acid; and the nitrogen-containing compound is selected from one or more of urea, melamine, acetylguanidine, benzoguanidine, cyanamide, dicyandiamide, thiourea, isocyanate, pyrimidone, or aminopyridine.

Optionally, in some embodiments, the metal oxide nanoparticles have hydroxyl dangling bonds on their surfaces; and/or

The polymer has multiple hydrogen bonds.

Optionally, in some embodiments, the metal oxide nanoparticles include _at least one of ZnO, _Znx1Mgy1O , _Znx1Aly1O , _{Znx2Mgy2Liz2O} , _SnO2 , NiO, _TiO2 , and _Znx1Sny1O , wherein x1+y1=1 or _x2 ₊ _y2 + _z2 =1.

Optionally, in some embodiments, in the electronic functional layer, the mass percentage of the metal oxide nanoparticles is 90%-99%, and the mass percentage of the polymer is 1% to 10%.

Optionally, in some embodiments, in the electronic functional layer, the mass percentage of the polymer is 3% to 7%.

Optionally, in some embodiments, in the electronic functional layer, the mass percentage of the polymer is 4% to 6%.

Optionally, in some embodiments, the average particle size of the metal oxide nanoparticles is 3 nanometers to 15 nanometers.

Optionally, in some embodiments, the first electrode and the second electrode are independently selected from a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal element electrode or an alloy electrode, the material of the doped metal oxide particle electrode 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 and aluminum-doped magnesium oxide, the composite electrode is selected from AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO ₂ /Ag/TiO ₂ , TiO ₂ /Al/TiO ₂ , ZnS/Ag/ZnS or ZnS/Al/ZnS, and the material of the metal electrode is selected from one or more of Ag, Al, Cu, Au, Mo, Pt, Ca and Ba; and/or

The material of the light-emitting layer is selected from quantum dot light-emitting materials, and the quantum dot light-emitting materials are selected from one or more of single-structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials. The material of the single-structure quantum dots, the core material of the core-shell structure quantum dots and the shell material of the core-shell structure quantum dots are respectively selected from at least one of the single-structure quantum dots selected from II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds. The II-VI The compound of the family is 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, At least one of CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, wherein the IV-VI group compound is selected from SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPb The III-V group compound is selected from at least one 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 the I-III-VI group compound is selected from at least one of CuInS ₂ , CuInSe ₂ and AgInS ₂ , the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors, the inorganic perovskite semiconductor has a general structural formula of AMX ₃ , wherein A is a Cs ⁺ ion, M is a divalent metal cation selected from at least one 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⁺ , X is a halogen anion selected from at least one of Cl ^- , Br ^- , and I ^- , and the organic-inorganic hybrid perovskite semiconductor has a general structural formula of BMX ₃ , wherein B is an organic amine cation selected from CH ₃ (CH ₂ ) _n-2 NH ₃ ⁺ or [NH ₃ (CH ₂ ) _n- 2 NH ₃ ] ²⁺ , wherein n ≥ 2, M is a divalent metal cation selected from at least one 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 selected from at least one of Cl ^- , Br ^- , and I ^- ; and/or

The light-emitting device also includes a hole transport layer and/or a hole injection layer arranged between the first electrode and the light-emitting layer; wherein the material of the hole transport layer is selected from one or more of PTAA, spiro-omeTAD, TAPC, NPB, CBP, TFB, PVK, Poly-TPD, TCTA, _MoS2 , _MoS3 , _MoSe2 , _MoSe3 and _WS3 ; the material of the hole injection layer is selected from one or more of HAT-CN, PEDOT:PSS, a derivative of PEDOT:PSS doped with s- _MoO3 , m-MTDATA, F4-TCQN and copper phthalocyanine.

The present application also provides a method for manufacturing a light emitting device, which comprises the following steps:

A first electrode, a light-emitting layer, an electronic functional layer, and a second electrode are sequentially stacked to form; or, a second electrode, an electronic functional layer, a light-emitting layer, and a first electrode are sequentially stacked to form;

Wherein, the electronic functional layer is formed by the following steps:

An electronic functional material solution is provided, wherein the electronic functional material solution comprises metal oxide nanoparticles, a polymer and Solvent; wherein the polymer includes one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone; the solvent includes one or more of isopropanol, ethylene glycol, heptyl alcohol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran;

A thin film is formed by a solution method and dried to obtain the electronic functional layer.

Optionally, in some embodiments, the ureidopyrimidone-containing polyurethane comprises polyurethane side chain grafted 2-urea-4[1H]-pyrimidone; and/or

The solvent comprises one or more of isopropanol, ethylene glycol, heptanol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran; and/or

In the supramolecular compound formed by the reaction of the fatty acid and the nitrogen-containing compound, the fatty acid is selected from oxalic acid, malonic acid, 1,7-pimelic acid, octadecanedioic acid, triacylglycerol, 2-hydroxybutyric acid, citric acid, and oxalosuccinic acid; and the nitrogen-containing compound is selected from one or more of urea, melamine, acetylguanidine, benzoguanidine, cyanamide, dicyandiamide, thiourea, isocyanate, pyrimidone, or aminopyridine.

The polymer has multiple hydrogen bonds.

The present application also provides a display device, which includes a light-emitting device as described in any one of the above items or a light-emitting device prepared by the method for manufacturing a light-emitting device as described in any one of the above items.

The light emitting device, the manufacturing method thereof and the display device of the present application add a polymer to the electronic functional layer containing metal oxide nanoparticles, and cracks appear in the electronic functional layer film formed by the metal oxide nanoparticles and the polymer. When the polymer is used in a photosensitive layer, it can repair cracks in the electronic functional layer and restore the electron injection and transmission functions, thereby improving the luminescence efficiency and device life.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solution in the present application, the drawings required for use in the description of the implementation methods will be briefly introduced below. Obviously, the drawings described below are only some implementation methods of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without paying any creative work.

FIG1 is a schematic diagram of the structure of a light-emitting device provided in one embodiment of the present application.

FIG. 2 is a schematic diagram of the structure of a display device provided in an embodiment of the present application.

FIG. 3 is a flow chart of a method for manufacturing a light-emitting device provided in one embodiment of the present application.

FIG. 4 is a flow chart of another method for manufacturing a light-emitting device provided in an embodiment of the present application.

FIG5 is an electron microscope photograph of the light-emitting device of Example 1 of the present application after a bending test.

FIG6 is an electron microscope photograph of the light emitting device of comparative example 1 of the present application after a bending test.

Embodiments of the present application

The technical solution in this application will be described clearly and completely below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of this application.

In this application, "and/or" describes the association relationship of associated objects, indicating that there may be three relationships. For example, A and/or B can mean: A exists alone, A and B exist at the same time, and B exists alone. A and B can be singular or plural.

In the present application, "at least one" means one or more, and "plurality" means two or more. "At least one", "at least one of the following" 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 all mean: a, b, c, a-b (i.e. a and b), a-c, b-c, or a-b-c, where a, b, c can be single or multiple, respectively.

In the present application, when another layer is formed “on” a certain layer, the so-called “on” is a broad concept, which may mean that the formed another layer is adjacent to the certain layer, or that there are other intervening structural layers between the another layer and the certain layer, for example, The first electrode is formed “on” the carrier functional layer. The so-called “on” may mean that the formed first electrode is adjacent to the first carrier functional layer, or may mean that there are other spacing structure layers between the first electrode and the first carrier functional layer, such as a light-emitting layer.

1 , the embodiment of the present application provides a light-emitting device 100, which includes a first electrode 10, a second electrode 20 disposed opposite to the first electrode 10, a light-emitting layer 30 disposed between the first electrode 10 and the second electrode 20, and an electronic functional layer 40 disposed between the second electrode 20 and the light-emitting layer 30. The electronic functional layer 40 includes metal oxide nanoparticles and a polymer.

The present application adds a polymer to the electronic functional layer 40 containing metal oxide nanoparticles. When cracks appear in the electronic functional layer film formed by the metal oxide nanoparticles and the polymer, the polymer can repair the cracks in the electronic functional layer 40 and restore the electron injection and transmission functions, thereby improving the luminous efficiency and device life.

Optionally, the first electrode 10 and the second electrode 20 are independently selected from a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal element electrode or an alloy electrode, the material of the doped metal oxide particle electrode 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 and aluminum-doped magnesium oxide, the composite electrode is selected from AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, _TiO2 _/ Ag/TiO2, _TiO2 /Al/ _TiO2 , ZnS/Ag/ZnS or ZnS/Al/ZnS, and the material of the metal electrode is selected from one or more of Ag, Al, Cu, Au, Mo, Pt, Ca and Ba.

Optionally, the material of the light-emitting layer 30 is selected from one or more quantum dot light-emitting materials, the quantum dot light-emitting materials are selected from one or more single-structure quantum dots, core-shell structure quantum dots and perovskite semiconductor materials, the material of the single-structure quantum dots, the core material of the core-shell structure quantum dots and the shell material of the core-shell structure quantum dots are respectively selected from at least one of the single-structure quantum dots selected from II-VI group compounds, IV-VI group compounds, III-V group compounds and I-III-VI group compounds, and the II-VI group 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, At least one of CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe, and the IV-VI group compound is at least one of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe and SnPbSTe , the III-V compound is selected from 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, At least one of GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs and InAlPSb, the I-III-VI group compound is selected from at least one of CuInS ₂ , CuInSe ₂ and AgInS ₂ , the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors, the inorganic perovskite semiconductor has a general structural formula of AMX ₃ , wherein A is a Cs ⁺ ion, M is a divalent metal cation selected from at least one 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 X is a halogen anion selected from Cl ^- , Br ^- , I ^-, the general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX ₃ , wherein B is an organic amine cation selected from CH ₃ (CH ₂ ) _n-2 NH ₃ ⁺ or [NH ₃ (CH ₂ ) _n NH ₃ ] ²⁺ , wherein n≥2, M is a divalent metal cation selected from at least one 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 X is a halogen anion selected from at least one of Cl ^- , Br ^- , and I ^- . Specifically, the quantum dot luminescent material can be a quantum dot material containing Cd, such as CdSe/CdS, CdZnSe/CdS, CdSe/CdS/ZnS CdZnSe/ZnSe/ZnS, etc., or a non-Cd quantum dot material, such as InP/ZnS, ZnSe/ZnS, etc. The photoluminescence wavelengths of the red, green and blue quantum dot materials are 615nm-635nm, 535nm-555nm and 465nm-480nm, respectively.

Optionally, the polymer includes one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone.

The polyurethane containing ureido-pyrimidone may include/be PU-g-UPy (polyurethane side chain grafted 2-urea-4[1H]-pyrimidone). The specific structural formula is as follows:

Supramolecular generally refers to two or more molecules combined by intermolecular interactions to form complex, organized aggregates, and maintain a certain integrity so that it has a clear microstructure and macroscopic characteristics. In the supramolecular compound of the reaction of fatty acids and nitrogen-containing compounds, the fatty acid is selected from oxalic acid, malonic acid, 1,7-pimelic acid, octadecanedioic acid, trisaccharic acid, 2-hydroxybutyric acid, citric acid, oxalosuccinic acid; the nitrogen-containing compound is selected from one or more of urea, melamine, acetylguanidine, benzoguanidine, cyanamide, dicyandiamide, thiourea, isocyanate, pyrimidone or aminopyridine.

The metal oxide nanoparticles have hydroxyl dangling bonds on their surface, while the above polymers have multiple hydrogen bonds. The metal oxide nanoparticles have a large number of hydroxyl dangling bonds on their surface, which is conducive to the formation of hydrogen bonds with the polymers with multiple hydrogen bonds, thus increasing stability. In addition, the self-healing temperature of the polymers with multiple hydrogen bonds is from room temperature to 120°C. For example, The cracks can be repaired by heating the functional layer 40 to 40° C. The repair method is simple and low in cost. Optionally, the polymer having hydroxyl dangling bonds includes but is not limited to the polymers listed above.

It is understood that the polymer in the electronic functional layer 40 of the present application is not limited to polymers with multiple hydrogen bonds, and it can also be a polymer that uses π-π stacking, host-guest interaction, metal-ligand interaction, ion interaction, etc. to repair cracks.

Optionally, the first electrode 10 is an anode, the second electrode 20 is a cathode, and the electronic functional layer 40 is an electron transport layer. The metal oxide nanoparticles used for the electronic functional layer 40 include at least one of ZnO, Zn _x1 Mg _y1 O, Zn _x1 Al _y1 O, Zn _x2 Mg _y2 Li _z2 O, SnO ₂ , NiO, TiO ₂ , and Zn _x1 Sn _y1 O, wherein x1+y1=1 or x2+y2+z2=1. In other embodiments of the present application, the electronic functional layer 40 may also be an electron injection layer.

Optionally, in the electronic functional layer 40, the mass percentage of the metal oxide nanoparticles is 90%-99%, and the mass percentage of the polymer is 1% to 10%. For example, the mass percentage of the polymer in the electronic functional layer 40 is 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9% or 10%. When the mass percentage of the polymer in the electronic functional layer 40 is greater than 10%, the content of the polymer is too high, which will affect the electron injection and cause the device performance to decrease; when the mass percentage of the polymer in the electronic functional layer 40 is less than 1%, the content of the polymer is too low to achieve the self-repairing effect.

Specifically, the mass percentage of the polymer in the electronic functional layer 40 is 3% to 7%. For example, the mass percentage of the polymer in the electronic functional layer 40 is 3%, 4%, 5%, 6% or 7%.

More specifically, the mass percentage of the polymer in the electronic functional layer 40 is 4% to 6%. For example, the mass percentage of the polymer in the electronic functional layer 40 is 4%, 5% or 6%.

In some embodiments, the average particle size of the metal oxide nanoparticles is 3 nanometers to 15 nanometers. For example, the average particle size of the metal oxide nanoparticles is 3 nanometers, 4 nanometers, 5 nanometers, 6 nanometers, 7 nanometers, 8 nanometers, 9 nanometers, 10 nanometers, 11 nanometers, 12 nanometers, 13 nanometers, 14 nanometers or 15 nanometers. When the average particle size of the metal oxide nanoparticles is too small, the surface defects of the nanoparticles increase, which will increase the luminescence quenching of the quantum dots; at the same time, the size uniformity is difficult to control during material preparation. When the average particle size of the metal oxide nanoparticles is too large, the difficulty of solvent dispersion of the nanoparticles increases, and they are easy to agglomerate, affecting the uniformity of film formation.

The light emitting device 100 further includes a hole transport layer 50 and a hole injection layer 60. The hole transport layer 50 is disposed between the first electrode 10 and the light emitting layer 30, and the hole injection layer 60 is disposed between the hole transport layer 50 and the first electrode 10.

The material of the hole transport layer 40 may be selected from, but is not limited to, poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-omeTAD), 4,4'-cyclohexylbis[N,N-di(4-methylphenyl)aniline] (TAPC), N,N'-bis(1-naphthyl)-N,N'-diphenyl-1,1'-diphenyl-4,4'-diamine (NPB), 4,4'-bis(N-carbazole)-1,1'-biphenyl (CBP), poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4'-(N-(p-butylphenyl))-1,1'-biphenyl)-2,4'-diamine] (PTAA ... One or more of triphenylamine (TFB), poly(9-vinylcarbazole) (PVK), polytriphenylamine (Poly-TPD), 4,4',4"-tri(carbazol-9-yl)triphenylamine (TCTA), _MoS2 , _MoS3 , _MoSe2 , _MoSe3 , and _WS3 .

The material of the hole injection layer 50 can be selected from, but not limited to, one or more of 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (HAT-CN), PEDOT:PSS, a derivative of PEDOT:PSS doped with s-MoO ₃ (PEDOT:PSS:s-MoO ₃ ), 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA), tetrafluorotetracyanoquinodimethane (F4-TCQN), and copper phthalocyanine.

In some embodiments, the light-emitting device is a flexible light-emitting device. Since the quantum dot light-emitting layer and the electron transport layer are both metal oxide nanoparticles, stress exists between the two layers of inorganic nanoparticles and at the edges of the two layers of inorganic nanoparticles and the inkjet-printed pixel definition layer, which causes cracks to appear during the bending process, affecting the application effect of the quantum dot light-emitting device in the flexible display. Therefore, by using the electronic functional layer of the present application in the flexible light-emitting device, cracks caused by bending or folding the flexible light-emitting device can be repaired.

Please refer to FIG. 2 , the present application further provides a display device 1 , which includes the light-emitting device 100 as described above and a light-emitting device manufactured by the following manufacturing method.

Referring to FIG. 3 , the present application further provides a method for manufacturing a light emitting device, which comprises the following steps:

sequentially stacking a first electrode, a light-emitting layer, an electronic functional layer, and a second electrode;

Wherein, the electronic functional layer is formed by the following steps:

An electronic functional material solution is provided, the electronic functional material solution comprising metal oxide nanoparticles, a polymer and a solvent, the polymer comprising one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone; the solvent comprising one or more of isopropanol, ethylene glycol, heptanol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran; a thin film is formed by a solution method and dried to obtain the electronic functional layer.

Referring to FIG. 4 , the present application also provides another method for manufacturing a light emitting device, which comprises the following steps:

The second electrode, the electronic functional layer, the light-emitting layer and the first electrode are sequentially stacked;

Wherein, the electronic functional layer is formed by the following steps:

An electronic functional material solution is provided, wherein the electronic functional material solution comprises metal oxide nanoparticles, a polymer and a solvent; wherein the polymer comprises one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone; and the solvent comprises isopropanol, ethylene glycol, heptyl alcohol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, One or more of dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide and tetrahydrofuran; forming a thin film by a solution method and drying the thin film to obtain the electronic functional layer.

In the above step of forming the electronic functional layer, optionally, the polymer includes one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone.

The ureidopyrimidone-containing polyurethane may include/be PU-g-UPy (polyurethane side chain grafted 2-urea-4[1H]-pyrimidone).

The metal oxide nanoparticles have hydroxyl dangling bonds on their surface and multiple hydrogen bonds in the polymer. The metal oxide nanoparticles have a large number of hydroxyl dangling bonds on their surface, which is conducive to the formation of hydrogen bonds with the polymers having multiple hydrogen bonds, thereby increasing stability. Moreover, the self-healing temperature of the polymers having multiple hydrogen bonds is from room temperature to 120°C. For example, cracks can be repaired by heating the electronic functional layer 40 to 40°C, and the repair method is simple and low in cost. Optionally, polymers having hydroxyl dangling bonds include but are not limited to the polymers listed above.

Optionally, the electronic functional layer is an electron transport layer. The metal oxide nanoparticles used for the electronic functional layer include at least one of ZnO, Zn _x1 Mg _y1 O, Zn _x1 Al _y1 O, Zn _x2 Mg _y2 Li _z2 O, SnO ₂ , NiO, TiO ₂ , and Zn _x1 Sn _y1 O, wherein x1+y1=1 or x2+y2+z2=1. In other embodiments of the present application, the electronic functional layer may also be an electron injection layer.

The solution used in the step of forming the electronic functional layer is selected from at least one of isopropyl alcohol, ethylene glycol, heptanol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide and tetrahydrofuran.

The electronic functional layer can be prepared by mixing polymer and metal oxide nanoparticles in proportion, printing them into pixels by solution method, and drying them into films. The solution method can be spin coating, printing, inkjet printing, blade coating, printing, dip-coating, immersion, spraying, roll coating, casting, slit coating, strip coating, etc.

It can be understood that the manufacturing method of the light-emitting device of the present application further includes the step of forming other film layers after the electronic functional layer is formed.

The light-emitting device manufactured by the manufacturing method of the present application can be self-repaired at room temperature to 120°C.

The present application is described in detail below through specific embodiments. The following embodiments are only partial embodiments of the present application and are not limitations of the present application.

Example 1

ITO is provided as a first electrode, and the thickness of the first electrode is 100 nm. A hole injection layer is prepared on the first electrode by inkjet printing, and the hole injection material includes PEDOT:PSS, the baking temperature is 150°C, and the thickness is 40 nm. A hole transport layer is prepared on the hole injection layer, and the material is TFB, and the thickness is 40 nm. A quantum dot light-emitting layer is prepared on the hole transport layer, and the quantum dot material is CdZnSe/ZnSe/ZnS, the wavelength is 630 nm, and the thickness is 50 nm. An electron transport layer is prepared on the quantum dot light-emitting layer, and the electron transport layer is a thin film formed by metal oxide nanoparticles and polymers, and the metal oxide nanoparticles are Zn _x Mg _y O, wherein x is 0.9 and y is 0.1. The polymer is a supramolecular compound synthesized from 1,2,4-cyclohexanetricarboxylic acid (CAS No.: 76784-95-7) and urea (CAS No.: 57-13-6), and the molar ratio of 1,2,4-cyclohexanetricarboxylic acid to urea is 1:1.5, the molecular weight of the supramolecular compound is 4650. The mass percentage of the polymer in the electronic functional layer is 5%, the baking temperature is 80°C, and the thickness is 40nm. The second electrode is evaporated on the electron transport layer, the material is Ag, and the thickness of the second electrode is 100nm to obtain a light-emitting device.

After the light emitting device of Example 1 was bent 100 times with a bending radius of 20 mm, the light emitting device was heated for self-repair at a self-repair temperature of 40° C. The crack condition was observed through an electron microscope, as shown in FIG5 .

Test device current efficiency and device life. Use FPD optical property measurement equipment from Foster to control the efficiency test system built by QE PRO spectrometer, Keithley 2400, and Keithley 6485 through LabView to measure and calculate the current efficiency. Use the 128-channel life test system customized by Guangzhou New Vision Company to test the life T95@1000nit. The system architecture is a 2mA constant current source to drive the light-emitting device. The photodiode detector and test system test the brightness (photocurrent) change of the light-emitting device. The brightness meter tests and calibrates the brightness (photocurrent) of the electroluminescent device to obtain the time it takes for the initial brightness of the light-emitting device to decay to 95%. The time it takes for the initial brightness of the light-emitting device to decay to 95% is converted to the aging time under 1000nit to obtain the life T95@1000nit.

The device current efficiency is 15 cd/A, and the device life (5% attenuation at 1000 nits) is 6000 h.

Example 2

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 10%.

The device current efficiency is 12cd/A, and the device life (5% attenuation at 1000nits) is 5200h.

Example 3

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 1%.

The device current efficiency is 13cd/A, and the device life (5% attenuation at 1000nits) is 4700h.

Example 4

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 3%.

The device current efficiency is 14 cd/A, and the device life (5% attenuation at 1000 nits) is 5100 h.

Example 5

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 4%.

The device current efficiency is 14.5 cd/A, and the device life (5% attenuation at 1000 nits) is 5600 h.

Example 6

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 6%.

The device current efficiency is 14 cd/A, and the device life (5% attenuation at 1000 nits) is 5700 h.

Example 7

This embodiment is substantially the same as Embodiment 1, except that the mass percentage of the polymer in the electronic functional layer in this embodiment is 7%.

The device current efficiency is 13.5 cd/A, and the device life (5% attenuation at 1000 nits) is 5400 h.

Example 8

This embodiment is basically the same as Embodiment 1, except that the polymer in this embodiment is a polyurethane of ureidopyrimidone. Specifically, the polymer is a polymer synthesized by introducing 5 molar % of 2-ureido-4-pyrimidone (CAS No.: 108-53-2) into a polyurethane polymer.

The device current efficiency is 15.5 cd/A, and the device life (5% attenuation at 1000 nits) is 5900 h.

Comparative Example 1

The comparative example is substantially the same as Example 1, except that the electron transport layer in Comparative Example 1 contains only inorganic nanoparticles but no polymer.

After the light emitting device of the comparative example was bent 100 times with a bending radius of 20 mm, the light emitting device was also heated, and crack conditions were observed through an electron microscope, as shown in FIG6 .

The device current efficiency is 10 cd/A, and the device life (5% attenuation at 1000 nits) is 4000 h.

Comparative Example 2

The comparative example is substantially the same as Example 1, except that the mass percentage of the polymer in the electronic functional layer in this example is 15%.

The device current efficiency is 6 cd/A, and the device life (5% attenuation at 1000 nits) is 1200 h.

From the comparison between Figure 5 and Figure 6, it can be seen that the electronic functional layer with added polymer undergoes self-repair at 40°C, and no obvious cracks are observed under an electron microscope. However, obvious cracks are observed under an electron microscope in the electronic functional layer without added polymer.

In addition, from the comparison between Examples 1 to 7 and Comparative Examples 1 and 2, it can be seen that the device with the electronic functional layer added with polymer has higher current efficiency and greatly improves the device life. When the mass percentage of the polymer is 1%, the current efficiency and device life are slightly improved, but not significantly. As the mass percentage of the polymer increases to 6%, the current efficiency and device life are However, as the mass percentage of polymer increases to more than 7%, the current efficiency and device life decrease. When the mass ratio of polymer increases to more than 10%, for example, 15%, the current efficiency and device life decrease sharply. It is speculated that this is because the proportion of polymer is too high, which hinders carrier transmission.

The above provides a detailed introduction to the implementation methods of the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The above description of the implementation methods is only used to help understand the present application. At the same time, for those skilled in the art, according to the ideas of the present application, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as limiting the present application.

Claims

A light emitting device, comprising:

a first electrode;

a second electrode, arranged opposite to the first electrode;

a light-emitting layer, disposed between the first electrode and the second electrode; and

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

The electronic functional layer comprises metal oxide nanoparticles and polymers, wherein the polymer comprises one or more of supramolecular compounds of fatty acids reacting with nitrogen-containing compounds, polyurethanes containing ureidopyrimidone, polyamides containing ureidopyrimidone, and polyacrylamides containing ureidopyrimidone.
The light-emitting device according to claim 1, wherein the polyurethane containing ureido-pyrimidone comprises polyurethane side chain grafted 2-urea-4[1H]-pyrimidone.
The light-emitting device according to claim 1, wherein in the supramolecular compound of the reaction of the fatty acid and the nitrogen-containing compound, the fatty acid is selected from oxalic acid, malonic acid, 1,7-pimelic acid, octadecanedioic acid, triacylglycerol, 2-hydroxybutyric acid, citric acid, oxalosuccinic acid; and the nitrogen-containing compound is selected from one or more of urea, melamine, acetylguanidine, benzoguanidine, cyanamide, dicyandiamide, thiourea, isocyanate, pyrimidone or aminopyridine.
The light-emitting device according to any one of claims 1 to 3, wherein the surface of the metal oxide nanoparticles has hydroxyl dangling bonds.
The light emitting device according to any one of claims 1 to 3, wherein the polymer has multiple hydrogen bonds.
The light emitting device according to claim 1 , wherein the metal oxide nanoparticles include at least one of ZnO, Znx1Mgy1O , Znx1Aly1O , Znx2Mgy2Liz2O, SnO2, NiO, TiO2, and Znx1Sny1O , wherein x1 + y1 =1 or x2 + y2 +z2=1.
The light-emitting device according to claim 1, wherein in the electronic functional layer, the mass percentage of the metal oxide nanoparticles is 90%-99%, and the mass percentage of the polymer is 1% to 10%.
The light-emitting device according to claim 1, wherein the mass percentage of the polymer in the electronic functional layer is 3% to 7%.
The light-emitting device according to claim 1, wherein the mass percentage of the polymer in the electronic functional layer is 4% to 6%.
The light-emitting device according to claim 1, wherein the average particle size of the metal oxide nanoparticles is 3 nanometers to 15 nanometers.
The light-emitting device according to claim 1, wherein the first electrode and the second electrode are independently selected from a doped metal oxide particle electrode, a composite electrode, a graphene electrode, a carbon nanotube electrode, a metal element electrode or an alloy electrode, the material of the doped metal oxide particle electrode 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 and aluminum-doped magnesium oxide, the composite electrode is selected from AZO/Ag/AZO, AZO/Al/AZO, ITO/Ag/ITO, ITO/Al/ITO, ZnO/Ag/ZnO, ZnO/Al/ZnO, TiO2 /Ag/ TiO2 , TiO2 /Al/ TiO2 , ZnS/Ag/ZnS or ZnS/Al/ZnS, and the material of the metal electrode is selected from one or more of Ag, Al, Cu, Au, Mo, Pt, Ca and Ba; and/or

The material of the light-emitting layer is selected from quantum dot light-emitting materials, and the quantum dot light-emitting materials are selected from one or more of single-structure quantum dots, core-shell quantum dots and perovskite semiconductor materials. The material of the single-structure quantum dots, the core material of the core-shell quantum dots and the shell material of the core-shell quantum dots are respectively selected from at least one of the single-structure quantum dots selected from II-VI compounds, IV-VI compounds, III-V compounds and I-III-VI compounds. The II-VI compounds are selected from CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, At least one of 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, wherein the IV The group VI compound is selected from at least one of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe, and the group III-V compound is selected from at least one of GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, Ga At least one of PAs, 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, wherein the I-III-VI group compound is selected from CuInS 2 , CuInSe 2 and AgInS 2 , the perovskite semiconductor material is selected from doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors, the inorganic perovskite semiconductor has a general structural formula of AMX 3 , wherein A is a Cs + ion, M is a divalent metal cation selected from at least one 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+ , X is a halogen anion selected from at least one of Cl - , Br - , and I - , and the organic-inorganic hybrid perovskite semiconductor has a general structural formula of BMX 3 , wherein B is an organic amine cation selected from CH 3 (CH 2 ) n-2 NH 3 + or [NH 3 (CH 2 ) n- 2 NH 3 ] 2+ , wherein n ≥ 2, M is a divalent metal cation selected from at least one 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 selected from Cl - , Br - , I - at least one; and/or

The light-emitting device also includes a hole transport layer and/or a hole injection layer arranged between the first electrode and the light-emitting layer; wherein the material of the hole transport layer is selected from one or more of PTAA, spiro-omeTAD, TAPC, NPB, CBP, TFB, PVK, Poly-TPD, TCTA, MoS2 , MoS3 , MoSe2 , MoSe3 and WS3 ; the material of the hole injection layer is selected from one or more of HAT-CN, PEDOT:PSS, a derivative of PEDOT:PSS doped with s- MoO3 , m-MTDATA, F4-TCQN and copper phthalocyanine.
A method for manufacturing a light emitting device, comprising the following steps:

A first electrode, a light-emitting layer, an electronic functional layer, and a second electrode are sequentially stacked to form; or, a second electrode, an electronic functional layer, a light-emitting layer, and a first electrode are sequentially stacked to form;

Wherein, the electronic functional layer is formed by the following steps:

Providing an electronic functional material solution, the electronic functional material solution comprising metal oxide nanoparticles, a polymer and a solvent; wherein the polymer comprises one or more of a supramolecular compound of a fatty acid reacted with a nitrogen-containing compound, a polyurethane containing ureidopyrimidone, a polyamide containing ureidopyrimidone, and a polyacrylamide containing ureidopyrimidone;

A thin film is formed by a solution method and dried to obtain the electronic functional layer.
The manufacturing method according to claim 12, wherein the polyurethane containing ureidopyrimidone comprises a polyurethane side chain grafted with 2-urea-4[1H]-pyrimidone; and/or

The solvent comprises one or more of isopropanol, ethylene glycol, heptanol, ethylene glycol monomethyl ether, diethylene glycol monobutyl ether, ethyl benzoate, methyl benzoate, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, and tetrahydrofuran; and/or

In the supramolecular compound formed by the reaction of the fatty acid and the nitrogen-containing compound, the fatty acid is selected from oxalic acid, malonic acid, 1,7-pimelic acid, octadecanedioic acid, triacylglycerol, 2-hydroxybutyric acid, citric acid, and oxalosuccinic acid; and the nitrogen-containing compound is selected from one or more of urea, melamine, acetylguanidine, benzoguanidine, cyanamide, dicyandiamide, thiourea, isocyanate, pyrimidone, or aminopyridine.
The production method according to any one of claims 12 to 13, wherein the metal oxide nanoparticles have hydroxyl dangling bonds on their surfaces; and/or

The polymer has multiple hydrogen bonds.
The manufacturing method according to claim 12, wherein the metal oxide nanoparticles include at least one of ZnO, Znx1Mgy1O, Znx1Aly1O, Znx2Mgy2Liz2O, SnO2 , NiO , TiO2 , and Znx1Sny1O , wherein x1 +y1=1 or x2 + y2 +z2=1.
The manufacturing method according to claim 12, wherein in the electronic functional layer, the mass percentage of the metal oxide nanoparticles is 90%-99%, and the mass percentage of the polymer is 1% to 10%.
The manufacturing method according to claim 12, wherein the mass percentage of the polymer in the electronic functional layer is 3% to 7%.
The manufacturing method according to claim 12, wherein the mass percentage of the polymer in the electronic functional layer is 4% to 6%.
The manufacturing method according to claim 12, wherein the average particle size of the metal oxide nanoparticles is 3 nm to 15 nm.
A display device, comprising a light-emitting device as claimed in any one of claims 1 to 11, or a light-emitting device manufactured by the method for manufacturing a light-emitting device as claimed in any one of claims 12 to 19.