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

Abstract

This application belongs to the field of display technology and relates to a light-emitting device and its fabrication method, as well as a display apparatus. The light-emitting device includes a first electrode, a first charge carrier functional layer, a light-emitting layer, and a second electrode stacked sequentially. The material of the first charge carrier functional layer includes an organic ammonium salt and a doped or undoped first metal oxide. The use of an organic ammonium salt and a doped or undoped first metal oxide in the first charge carrier functional layer of this application can improve the hole mobility of the first charge carrier functional layer, improve the injection balance of holes and electrons in the light-emitting layer, and improve the luminous efficiency and lifespan of the light-emitting device.

Description

Technical Field

[0001] This application relates to the field of display technology, and more specifically, to a light-emitting device, a method for preparing the same, and a display device. Background Technology

[0002] Quantum dot light-emitting diodes (QLEDs) are a new type of display technology that has emerged rapidly in recent years. Quantum dot light-emitting diodes are devices that use colloidal quantum dots as the light-emitting layer. By introducing the quantum dot light-emitting layer between different conductive materials, light of the desired wavelength can be obtained.

[0003] In existing light-emitting devices, the hole mobility is relatively low, and the ability of holes to inject into the light-emitting layer is generally weaker than that of electrons, which affects the luminous efficiency and lifespan of the light-emitting devices. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a light-emitting device, which employs the following technical solution:

[0005] A light-emitting device, the light-emitting device comprising a first electrode, a first carrier functional layer, a light-emitting layer and a second electrode arranged in sequence;

[0006] The material of the first carrier functional layer includes an organic ammonium salt and a first metal oxide.

[0007] To address the aforementioned technical problems, this application provides a method for fabricating a light-emitting device, employing the technical solution described below:

[0008] A method for fabricating a light-emitting device includes the following fabrication steps:

[0009] Provide the first electrode;

[0010] A first carrier functional layer is formed on the first electrode;

[0011] A light-emitting layer is disposed on the first carrier functional layer;

[0012] A second electrode is disposed on the light-emitting layer to obtain the light-emitting device;

[0013] or,

[0014] Provide a second electrode,

[0015] A light-emitting layer is disposed on the second electrode;

[0016] A first carrier functional layer is formed on the light-emitting layer;

[0017] A first electrode is disposed on the first carrier functional layer to obtain the light-emitting device;

[0018] The material of the first carrier functional layer includes an organic ammonium salt and a first metal oxide.

[0019] Accordingly, this application provides a display device, which includes a light-emitting device as described above or a light-emitting device prepared by the method described above.

[0020] Compared with the prior art, the embodiments of this application have the following main advantages:

[0021] The material of the first carrier functional layer in this application includes an organic ammonium salt and a first metal oxide, which can improve the hole mobility of the first carrier functional layer and improve the luminous efficiency and lifespan of the light-emitting device. Attached Figure Description

[0022] To more clearly illustrate the solutions in this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 A schematic diagram of one embodiment of the light-emitting device provided in the application;

[0024] Figure 2 A schematic diagram of another embodiment of the light-emitting device provided in the application;

[0025] Figure 3 A flowchart illustrating the fabrication process of one embodiment of the light-emitting device provided in the application;

[0026] Figure 4 A flowchart illustrating the fabrication process of another embodiment of the light-emitting device provided in the application.

[0027] Reference numerals in the figures: 1. First electrode; 2. First carrier functional layer; 3. Light-emitting layer; 4. Auxiliary layer; 5. Second carrier functional layer; 6. Second electrode. Detailed Implementation

[0028] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application. Furthermore, it should be understood that the specific embodiments described herein are only for illustration and explanation of this application and are not intended to limit this application.

[0029] In this application, unless otherwise stated, directional terms such as "upper" and "lower" generally refer to the upper and lower positions of the device in its actual use or operating state, specifically the orientation shown in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. Furthermore, in the description of this application, the term "comprising" means "including but not limited to". The terms first, second, third, etc., are used merely as illustrative purposes and do not impose numerical requirements or establish a numerical order.

[0030] In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. A and B can be singular or plural.

[0031] In this application, "at least one" means one or more, and "more than one" 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 or multiple items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0032] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely 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 single numerical 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 single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.

[0033] In this application, aromatic group, aromatic group, aromatic family, and aromatic ring system have the same meaning and can be used interchangeably.

[0034] In this application, "substitution" means that the hydrogen atom in the substituent is replaced by the substituent.

[0035] In this application, "substituted or unsubstituted" means that the defined group may or may not be substituted. When the defined group is substituted, it should be understood that the defined group may be substituted by one or more substituents R1, wherein R1 is selected from, but is not limited to: deuterium, cyano, isocyano, nitro or halogen, alkyl containing 1-20 carbon atoms, heterocyclic group containing 3-20 ring atoms, aromatic group containing 6-20 ring atoms, heteroaromatic group containing 5-20 ring atoms, silyl, carbonyl, alkoxycarbonyl, aryloxycarbonyl, carbamoyl, haloformyl, formyl, isocyanate, thiocyanate, isothiocyanate, hydroxyl, trifluoromethyl, and the above groups may also be further substituted by substituents acceptable in the art.

[0036] In this application, "ring atom number" refers to the number of atoms in the ring itself of a structural compound (e.g., a monocyclic compound, a fused-ring compound, a cross-linked compound, a carbocyclic compound, or a heterocyclic compound) obtained by atomic bonding to form a ring. When the ring is substituted by a substituent, the atoms contained in the substituent are not included in the ring-forming atoms. The same applies to the "ring atom number" described below unless otherwise specified. For example, a benzene ring has 6 ring atoms, a naphthalene ring has 10 ring atoms, and a thiophene group has 5 ring atoms.

[0037] "Aryl or aromatic group" refers to an aromatic hydrocarbon group derived from an aromatic ring compound by removing one hydrogen atom. It can be a monocyclic aryl, a fused-ring aryl, or a polycyclic aryl. For polycyclic ring species, at least one is an aromatic ring system. For example, "substituted or unsubstituted aryl having 6 to 40 ring atoms" means an aryl containing 6 to 40 ring atoms, optionally substituted or unsubstituted aryl having 6 to 30 ring atoms, optionally substituted or unsubstituted aryl having 6 to 18 ring atoms, or optionally substituted or unsubstituted aryl having 6 to 14 ring atoms, with the aryl group optionally further substituted; suitable examples include, but are not limited to: phenyl, biphenyl, terphenyl, naphthyl, anthracene, phenanthrene, fluoranyl, triphenylene, pyrene, perylene, tetraphenyl, fluorenyl, dinaphthylphenyl, acenaphthyl, and their derivatives. Understandably, multiple aryl groups can also be interrupted by short non-aromatic units (e.g., <10% non-H atoms, such as C, N, or O atoms), specifically acenaphthene, fluorene, or 9,9-diarylfluorene, triarylamine, and diaryl ether systems should also be included in the definition of aryl.

[0038] "Heteroaryl or heteroaromatic group" refers to an aryl group in which at least one carbon atom is replaced by a non-carbon atom, which can be an N atom, O atom, S atom, etc. For example, "substituted or unsubstituted heteroaryl group having 5 to 40 ring atoms" refers to a heteroaryl group having 5 to 40 ring atoms, optionally substituted or unsubstituted heteroaryl group having 6 to 30 ring atoms, optionally substituted or unsubstituted heteroaryl group having 6 to 18 ring atoms, or optionally substituted or unsubstituted heteroaryl group having 6 to 14 ring atoms, and the heteroaryl group may optionally be further substituted. Suitable examples include, but are not limited to: thiophene, furanyl, pyrroleyl, imidazole, triazolyl, imidazoleyl, diazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridineyl, pyridazinyl, etc. Azinyl, quinolinyl, quinazolinyl, quinoxalinyl, phthalazinyl, pyridinylpyrimidinyl, pyridinylpyrazinyl, pyrazinylpyrazinyl, isoquinolinyl, indolyl, carbazoleyl, benzothiopheneyl, benzofuranyl, indolyl, carbazoleyl, pyrroloimidazolyl, pyrrolopyrrololyl, thienopyrrololyl, thienopyrrololyl, furanolol, furanol, thienofuranyl, benzoisoxazolyl, benzoisothiazolyl, benzoimidazolyl, quinolinyl, isoquinolinyl, o-diazonaphthyl, quinoxalinyl, phenanthridine, primidyl, quinazolinyl, quinazolinone, dibenzothiopheneyl, dibenzofuranyl, carbazoleyl and their derivatives.

[0039] In this application, "alkyl" can mean straight-chain, branched, and / or cyclic alkyl. The number of carbon atoms in an alkyl group can be 1 to 50, 1 to 30, 1 to 20, 1 to 10, or 1 to 6. Phrases containing this term, such as "C1-9 alkyl," refer to alkyl groups containing 1 to 9 carbon atoms, and each time it appears, it can independently be C1 alkyl, C2 alkyl, C3 alkyl, C4 alkyl, C5 alkyl, C6 alkyl, C7 alkyl, C8 alkyl, or C9 alkyl. Non-limiting examples of alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, isobutyl, 2-ethylbutyl, 3,3-dimethylbutyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, cyclopentyl, 1-methylpentyl, 3-methylpentyl, 2-ethylpentyl, 4-methyl-2-pentyl, n-hexyl, 1-methylhexyl, 2-ethylhexyl, 2-butylhexyl, cyclohexyl, 4-methylcyclohexyl, 4-tert-butylcyclohexyl, n-heptyl, 1-methylheptyl, 2,2-dimethylheptyl, 2-ethylheptyl, 2-butylheptyl, n-octyl, tert-octyl, 2-ethyloctyl, 2-butyloctyl, 2-hexyloctyl, 3,7-dimethyloctyl, cyclooctyl, n-nonyl, n-decyl, adamantyl, 2-ethyldecyl, 2-butyldecyl 2-Hexyldecyl, 2-Octylide, undecyl, dodecyl, 2-Ethyldodecyl, 2-Butyldodecyl, 2-Hexyldodecyl, 2-Octylide, tridecyl, tetradecyl, pentadecyl, hexadecyl, 2-Ethylhexadecyl, 2-Butylhexadecyl, 2-Hexylhexadecyl, 2-Octylide, heptadecanyl, octadecyl, nonadecanyl, eicosyl, 2-Ethyleicosyl, 2-Butyleicosyl, 2-Hexyleicosyl, 2-Octylide, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecanyl, octadecyl, nonadecanyl, triadecyl, adamantane, etc.

[0040] In existing light-emitting devices, the first carrier functional layer is mainly made of inorganic materials. The hole injection rate is generally much smaller than the electron injection rate, which easily causes an imbalance between the injection of electrons and holes in the light-emitting layer, thus limiting the improvement of the luminous efficiency and lifespan of the light-emitting device.

[0041] To address the above problems, this application provides a light-emitting device, please refer to the embodiments described above. Figure 1 and Figure 2 ,in, Figure 1 This is a schematic diagram of a positively positioned light-emitting device. Figure 2 This is a schematic diagram of an inverted light-emitting device.

[0042] The light-emitting device includes a first electrode 1, a first charge carrier functional layer 2, a light-emitting layer 3, and a second electrode 6 stacked sequentially; wherein the material of the first charge carrier functional layer 2 includes an organic ammonium salt and a first metal oxide.

[0043] In this embodiment, the material of the first carrier functional layer 2 includes organic ammonium salt and doped or undoped first metal oxide, which can improve the hole mobility of the first carrier functional layer 2, improve the injection balance of holes and electrons in the light-emitting layer 3, and improve the luminous efficiency and lifespan of the light-emitting device.

[0044] In some embodiments, the first metal oxide comprises one or more of the following: doped or undoped tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element in the doped oxide comprises one or more of Li, Ca, Ga, Mg, Ce, Al, and Zn. In a preferred embodiment, the first metal oxide is molybdenum oxide, which exhibits good chemical stability and maintains stable performance in various environments.

[0045] In some embodiments, the average thickness of the first carrier functional layer 2 is 1 nm to 50 nm, and optionally, the average thickness of the first carrier functional layer is 5 nm to 30 nm. By setting an appropriate thickness for the first carrier functional layer 2, the mobility of holes in the first carrier functional layer 2 can be further guaranteed, the injection balance of holes and electrons in the light-emitting layer 3 can be improved, and the luminous efficiency and lifespan of the light-emitting device can be increased.

[0046] In some optional embodiments of this example, the average thickness of the first carrier functional layer 2 is within the range of any one or any two of the following: 1nm, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc.

[0047] In some embodiments, in the first carrier functional layer 2, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is 1:(0.001 to 0.3), and optionally, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.01 to 0.2).

[0048] In some optional embodiments of this example, in the first carrier functional layer 2, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is any one of the following ratios or any two of the following: 1:0.001, 1:0.005, 1:0.01, 1:0.05, 1:0.1, 1:0.15, 1:0.25, 1:0.3, and the optimal mass ratio is 100:15.

[0049] In some embodiments, the cations in the organic ammonium salt are bonded to the first metal oxide via hydrogen bonds. Specifically, the first metal oxide generates unsaturated metal ions and oxygen ions due to factors such as lattice distortion or dislocations, resulting in an electronegativity difference. This electronegativity difference causes the first metal oxide to exhibit a photocatalytic effect under illumination. The free radicals generated by the photocatalytic effect can lead to the degradation of adjacent functional layers, severely affecting the luminous efficiency of the light-emitting device. The ammonium ions in the organic ammonium salt have a strong positive charge. The protons in the ammonium ions can form a strong hydrogen bond interaction (NH··O) with the oxygen ions in the first metal oxide. On the one hand, this hydrogen bond interaction can fix the oxygen ions generated by the first metal oxide, reducing photocatalytic activity, inhibiting the degradation of nearby functional layers by free radicals in the first carrier functional layer 2, and improving the stability of the light-emitting device. On the other hand, fixing oxygen ions through hydrogen bonds inhibits the movement of impurity oxygen ions, which helps reduce oxygen vacancy defects in the first metal oxide, improves the hole mobility and hole injection efficiency of the first carrier functional layer 2, improves the injection balance of holes and electrons in the light-emitting layer 3, and improves the luminous efficiency and lifespan of the light-emitting device.

[0050] In some embodiments, the organic ammonium salt has the structural formula shown in Formula I:

[0051]

[0052] Among them, X - It is an anion, selected from Cl. - ,Br - and I - One of them;

[0053] The substituent R is selected from hydrogen, C1-C25 straight-chain alkyl, C2-C25 branched alkyl, C3-C25 cycloalkyl, substituted or unsubstituted aromatic group having 6 to 20 ring atoms, and substituted or unsubstituted heteroaryl group having 6 to 20 ring atoms. The substituted substituent is selected from halogen, hydroxyl, carboxyl, nitro, sulfonic acid, aldehyde, mercapto, cyano, ether alkyl, carbonyl alkyl. The heteroatom in the heteroaryl group is N, S, O, P, Si, or B, and the number of heteroatoms is 1 to 20.

[0054] In some embodiments, the organic ammonium salt is selected from any of the following structures:

[0055]

[0056]

[0057] In some embodiments, the light-emitting device further includes an auxiliary layer 4 and a second carrier functional layer 5, which are located between the light-emitting layer 3 and the second electrode 6, wherein the auxiliary layer 4 is closer to the light-emitting layer 3 than the second carrier functional layer 5. Specifically, the auxiliary layer 4 can regulate the transmission efficiency of electrons from the second carrier functional layer 5 to the light-emitting layer 3, improving the injection balance of holes and electrons in the light-emitting layer 3.

[0058] In some embodiments, the material of the auxiliary layer 4 includes the organic ammonium salt. The organic ammonium salt itself does not have electronic conductivity. An organic ammonium salt auxiliary layer 4 of a certain thickness can block electrons, reduce electron transmission efficiency, prevent electrons from being transmitted too quickly and excessively from the second carrier functional layer 5 to the light-emitting layer 3, and improve the injection balance of holes and electrons in the light-emitting layer 3.

[0059] In some embodiments, the material of the second carrier functional layer 5 includes a second metal oxide, which is selected from one or more of doped or undoped zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium. In this embodiment, by providing an organic ammonium salt auxiliary layer 4 at the interface of the metal oxide second carrier functional layer 5, the ammonium ions at the end of the organic ammonium salt interact with oxygen in the second metal oxide, causing the charge on the ammonium ions to transfer to the second metal oxide. This increases the conduction band energy level and electron injection barrier of the second carrier functional layer 5, reduces the injection of electrons from the second electrode 6 into the second carrier functional layer 5, and avoids excessive and rapid electron transfer from the second electrode 6 to the second carrier functional layer 5.

[0060] Furthermore, the average thickness of the second carrier functional layer 5 is 1 nm to 50 nm, optionally, the average thickness of the second carrier functional layer 5 is 8 nm to 45 nm, optionally, the average thickness of the second carrier functional layer 5 is 25 nm to 35 nm.

[0061] In some optional embodiments of this example, the average thickness of the second carrier functional layer 5 is within the range of any one or any two of the following: 1nm, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, 40nm, 45nm, 50nm, etc.

[0062] Furthermore, the average thickness of the auxiliary layer 4 is 0.1 nm to 20 nm, optionally, the average thickness of the auxiliary layer 4 is 1 nm to 15 nm, and optionally, the average thickness of the auxiliary layer 4 is 2 nm to 5 nm. In this embodiment, by setting an appropriate thickness for the empty auxiliary layer 4, electron transport efficiency is ensured; the thickness of the auxiliary layer 4 varies depending on the electron transport efficiency requirements, and adjusting the thickness of the auxiliary layer 4 can balance the positive load carriers, which is not limited in this application.

[0063] In some optional embodiments of this example, the average thickness of the auxiliary layer 4 is within the range of any one or any two of 0.1nm, 0.5nm, 1nm, 4nm, 7nm, 10nm, 13nm, 16nm, 18nm, 20nm, etc.

[0064] Furthermore, the average thickness of the first electrode 1 is 80 nm to 1000 nm.

[0065] In some optional embodiments of this example, the average thickness of the first electrode 1 is within the range of any one or any two of 80nm, 100nm, 200nm, 300nm, 400nm, 500nm, 600nm, 700nm, 800nm, 900nm, 1000nm, etc.

[0066] Furthermore, the average thickness of the light-emitting layer 3 is 2 nm to 100 nm.

[0067] In some optional embodiments of this example, the average thickness of the light-emitting layer 3 is within the range of any one or any two of the following: 2nm, 10nm, 20nm, 30nm, 40nm, 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, etc.

[0068] Furthermore, the average thickness of the second electrode 6 is 5 nm to 50 nm.

[0069] In some optional embodiments of this example, the average thickness of the second electrode 6 is within the range of any one or any two of 5nm, 10nm, 20nm, 30nm, 40nm, 50nm, etc.

[0070] In some embodiments, the first electrode 1 and the second electrode 6 are each selected from one or more of a metal electrode, a silicon-carbon electrode, a doped or undoped metal oxide electrode, and a composite electrode; wherein, the material of the metal electrode is selected from at least one of Al, Ag, Cu, Mo, Au, Ba, Ca, and Mg; the material of the silicon-carbon electrode is selected from at least one of silicon, graphite, carbon nanotubes, graphene, and carbon fiber; the material of the doped or undoped metal oxide electrode is selected from at least one of ITO, FTO, ATO, AZO, GZO, IZO, MZO, and AMO; and the material of the composite electrode is selected from at least one of 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, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2.

[0071] In some embodiments, the material of the light-emitting layer 3 includes at least one of organic light-emitting materials, single-structure quantum dots, and core-shell structure quantum dots. The organic light-emitting material is selected from one or more of the following: 4,4'-bis(N-carbazole)-1,1'-biphenyl:tris[2-(p-tolyl)pyridinium(III), 4,4',4”-tris(carbazole-9-yl)triphenylamine:tris[2-(p-tolyl)pyridinium, diaromatic anthracene 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, thermally activated delayed materials, polymers containing BN covalent bonds, hybrid localized charge transfer excited-state materials, and excitocomplex light-emitting materials. The shell of the core-shell structure quantum dot includes one or more layers.The material of the single-structure quantum dot, the core material of the core-shell structure quantum dot, and the shell material of the core-shell structure quantum dot are each selected from at least one of group III-VI compounds, group IV-VI compounds, group II-IV compounds, and group III-VI compounds. The group III-VI compounds include 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, CdZn One or more of STe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; group IV-VI 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; II Group IV compounds include 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; Group III-VI compounds include at least one of CuInS2, CuInSe2, and AgInS2.

[0072] In some embodiments, the first carrier functional layer 2 is a hole functional layer, and the material of the hole functional layer includes an organic ammonium salt and a first metal oxide. The first metal oxide includes one or more of the following: doped or undoped tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element of the doped oxide includes one or more of the following: Li, Ca, Ga, Mg, Ce, Al, and Zn.

[0073] In some embodiments, the second carrier functional layer 5 is an electronic functional layer, and the material of the electronic functional layer includes a second metal oxide. The second metal oxide is selected from one or more of doped or undoped zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

[0074] This application also provides a method for manufacturing a light-emitting device according to any of the above examples, such as... Figure 3 As shown, it includes the following steps:

[0075] Step S11: Provide the first electrode.

[0076] Step S12: Form a first carrier functional layer on the first electrode, wherein the material of the first carrier functional layer includes an organic ammonium salt and a doped or undoped first metal oxide.

[0077] In this embodiment, the material of the first carrier functional layer includes an organic ammonium salt and a doped or undoped first metal oxide, which can improve the hole mobility of the first carrier functional layer, improve the injection balance of holes and electrons in the light-emitting layer, and improve the luminous efficiency and lifespan of the light-emitting device.

[0078] Furthermore, the first carrier functional layer is formed in the following manner:

[0079] A first mixed solution is provided, the first mixed solution comprising a doped or undoped first metal oxide solution and an organic ammonium salt solution;

[0080] The first mixed solution is used to form a first thin film on the first electrode; and

[0081] The first thin film is dried to obtain the first carrier functional layer.

[0082] Specifically, a doped or undoped first metal oxide solution and an organic ammonium salt solution are mixed in a certain mass ratio and stirred at a temperature ranging from 25°C to 150°C for 1 min to 240 min to obtain a first mixed solution. The first mixed solution is then used to form a first thin film on the first electrode via a solution method. The first thin film is then dried at a certain temperature to remove the solvent, thereby obtaining the first carrier functional layer. In some embodiments, the drying temperature is 40°C to 150°C, and the drying time is 1 to 60 min.

[0083] Optionally, the mixing temperature of the first mixed solution is 40℃~120℃, or 60℃~70℃; and / or, the stirring time of the first mixed solution is 1min~240min, or 10min~120min, or 30min~60min.

[0084] Optionally, the drying temperature is 70℃~120℃, or 80℃~100℃; and / or, the drying time is 1min~60min, or 2min~45min, or 10min~30min.

[0085] In some embodiments, in the first mixed solution, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is 1:(0.001 to 0.3), and optionally, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.01 to 0.2).

[0086] In some optional embodiments of this example, in the first mixed solution, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is any one of the following ratios or any range between any two ratios: 1:0.001, 1:0.005, 1:0.01, 1:0.05, 1:0.1, 1:0.15, 1:0.25, 1:0.3, etc.

[0087] In this embodiment, by appropriately setting the mass ratio of the first metal oxide to the organic ammonium salt in the first carrier functional layer, the hole mobility and hole injection efficiency of the first carrier functional layer can be effectively improved, thereby improving the injection balance of holes and electrons in the light-emitting layer.

[0088] In some embodiments, the solvent in the doped or undoped first metal oxide solution includes at least one of methanol, ethanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, 2-methoxyethanol, DMF, DMSO, and 2-ethoxyethanol.

[0089] In some embodiments, the first metal oxide includes one or more of the following: tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide, and the doping element of the doped oxide includes one or more of the following: Li, Ca, Ga, Mg, Ce, Al, and Zn.

[0090] In some embodiments, the solvent in the organic ammonium salt solution includes at least one of methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol.

[0091] In some embodiments, the organic ammonium salt has the structural formula shown in Formula I:

[0092]

[0093] Among them, X - It is an anion, selected from Cl. - ,Br - and I - One of them;

[0094] The substituent R is selected from hydrogen, C1-C25 straight-chain alkyl, C2-C25 branched alkyl, C3-C25 cycloalkyl, substituted or unsubstituted aromatic group having 6 to 20 ring atoms, and substituted or unsubstituted heteroaryl group having 6 to 20 ring atoms. The substituted substituent is selected from halogen, hydroxyl, carboxyl, nitro, sulfonic acid, aldehyde, mercapto, cyano, ether alkyl, carbonyl alkyl. The heteroatom in the heteroaryl group is N, S, O, P, Si, or B, and the number of heteroatoms is 1 to 20.

[0095] In some embodiments, the organic ammonium salt is selected from any of the following structures:

[0096]

[0097] Step S13: Set a light-emitting layer on the first carrier functional layer.

[0098] Step S14: An auxiliary layer is disposed on the light-emitting layer, wherein the material of the auxiliary layer includes the organic ammonium salt.

[0099] Furthermore, a second mixed solution is provided, the second mixed solution comprising an organic ammonium salt solution and a first solvent;

[0100] The second mixed solution is used to form a second thin film on the light-emitting layer; and

[0101] The second film is dried to obtain the auxiliary layer.

[0102] Specifically, the organic ammonium salt solution and the first solvent are mixed in a certain mass ratio and stirred for 1 min to 240 min at a temperature of 25℃ to 150℃ to obtain a second mixed solution. The second mixed solution is then used to form a second thin film on the light-emitting layer by a solution method, and the second thin film is dried at a certain temperature to remove the solvent, thereby obtaining the auxiliary layer.

[0103] Optionally, the mixing temperature of the second mixed solution is 40℃~120℃, or 60℃~70℃; and / or, optionally, the stirring time of the second mixed solution is 10min~120min, or 30min~60min.

[0104] In this embodiment, the drying temperature is 25℃~120℃, and the drying time is 0.5min~60min. Optionally, the drying temperature is 50℃~100℃, or 60℃~80℃; and / or, optionally, the drying time is 2min~40min, or 10min~30min.

[0105] In some embodiments, the first solvent includes at least one selected from chlorobenzene, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol.

[0106] In some embodiments, the organic ammonium salt in the second mixed solution has a mass percentage of 1% to 50%, optionally, a mass percentage of 5% to 30%, or optionally, a mass percentage of 10% to 20%. In some optional embodiments of this example, the mass percentage of the organic ammonium salt is any one or any two of 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc.

[0107] Step S15: A second carrier functional layer is formed on the auxiliary layer. The material of the second carrier functional layer includes a second metal oxide. The second metal oxide is selected from one or more of the following: zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

[0108] Step S16: A second electrode is disposed on the second carrier functional layer to obtain the light-emitting device.

[0109] It is understood that the light-emitting device is a positively positioned light-emitting device.

[0110] Please see Figure 4 Another method for fabricating a light-emitting device provided in this application includes the following steps:

[0111] Step S21: Provide a second electrode.

[0112] Step S22: A second carrier functional layer is formed on the second electrode. The material of the second carrier functional layer includes a second metal oxide. The second metal oxide is selected from one or more of the following: zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

[0113] Step S23: An auxiliary layer is provided on the second carrier functional layer, wherein the material of the auxiliary layer includes the organic ammonium salt.

[0114] Furthermore, a second mixed solution is provided, the second mixed solution comprising an organic ammonium salt solution and a first solvent;

[0115] The second mixed solution is used to form a second thin film on the second carrier functional layer; and

[0116] The second film is dried to obtain the auxiliary layer.

[0117] Specifically, the organic ammonium salt solution and the first solvent are mixed in a certain mass ratio and stirred for 1 min to 240 min at a temperature of 25℃ to 150℃ to obtain a second mixed solution. The second mixed solution is then used to form a second thin film on the second carrier functional layer by a solution method. The second thin film is then dried at a certain temperature to remove the solvent, thereby obtaining the auxiliary layer.

[0118] In this embodiment, the drying temperature is 25℃~120℃, and the drying time is 0.5min~60min.

[0119] In some embodiments, the first solvent includes at least one selected from chlorobenzene, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol.

[0120] In some embodiments, the organic ammonium salt in the second mixed solution has a mass percentage of 1% to 50%, optionally, a mass percentage of 5% to 30%, or optionally, a mass percentage of 10% to 20%. In some optional embodiments of this example, the mass percentage of the organic ammonium salt is any one or any two of 1%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, etc.

[0121] Step S24: Set a light-emitting layer on the auxiliary layer.

[0122] Step S25: A first carrier functional layer is formed on the light-emitting layer, wherein the material of the first carrier functional layer includes an organic ammonium salt and a doped or undoped first metal oxide.

[0123] Furthermore, the first carrier functional layer is formed in the following manner:

[0124] A first mixed solution is provided, the first mixed solution comprising a doped or undoped first metal oxide solution and an organic ammonium salt solution;

[0125] The first mixed solution is used to form a first thin film on the light-emitting layer; and

[0126] The first thin film is dried to obtain the first carrier functional layer.

[0127] Specifically, a doped or undoped first metal oxide solution and an organic ammonium salt solution are mixed in a certain mass ratio and stirred at a temperature ranging from 25°C to 150°C for 1 min to 240 min to obtain a first mixed solution. The first mixed solution is then used to form a first thin film on the light-emitting layer via a solution method. The first thin film is then dried at a certain temperature to remove the solvent, thereby obtaining the first carrier functional layer. In some embodiments, the drying temperature is 40°C to 150°C, and the drying time is 1 to 60 min.

[0128] In some embodiments, in the first mixed solution, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is 1:(0.001 to 0.3), and optionally, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.01 to 0.2).

[0129] In some optional embodiments of this example, in the first mixed solution, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is any one of the following ratios or any range between any two ratios: 1:0.001, 1:0.005, 1:0.01, 1:0.05, 1:0.1, 1:0.15, 1:0.25, 1:0.3, etc.

[0130] In some embodiments, the solvent in the doped or undoped first metal oxide solution includes at least one of methanol, ethanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, 2-methoxyethanol, DMF, DMSO, and 2-ethoxyethanol.

[0131] In some embodiments, the first metal oxide includes one or more of the following: tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide, and the doping element of the doped oxide includes one or more of the following: Li, Ca, Ga, Mg, Ce, Al, and Zn.

[0132] In some embodiments, the solvent in the organic ammonium salt solution includes at least one of methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol.

[0133] In some embodiments, the organic ammonium salt has the structural formula shown in Formula I:

[0134]

[0135] Among them, X - It is an anion, selected from Cl.- ,Br - and I - One of them;

[0136] The substituent R is selected from hydrogen, C1-C25 straight-chain alkyl, C2-C25 branched alkyl, C3-C25 cycloalkyl, substituted or unsubstituted aromatic group having 6 to 20 ring atoms, and substituted or unsubstituted heteroaryl group having 6 to 20 ring atoms. The substituted substituent is selected from halogen, hydroxyl, carboxyl, nitro, sulfonic acid, aldehyde, mercapto, cyano, ether alkyl, carbonyl alkyl. The heteroatom in the heteroaryl group is N, S, O, P, Si, or B, and the number of heteroatoms is 1 to 20.

[0137] In some embodiments, the organic ammonium salt is selected from any of the following structures:

[0138]

[0139] Step S26: A first electrode is disposed on the first carrier functional layer to obtain the light-emitting device.

[0140] It is understood that the light-emitting device is an inverted light-emitting device.

[0141] The materials of the aforementioned functional layers, such as the first electrode, the light-emitting layer, and the second electrode, are the same as those described above and will not be repeated here.

[0142] The preparation methods of the aforementioned first electrode, light-emitting layer, second charge carrier functional layer, second electrode, etc., can adopt conventional preparation methods in the art, including: solution method or vapor deposition method; optionally, the solution method includes, but is not limited to, one or more of the following: spin coating, printing method, blade coating, dip-coating method, immersion method, spraying method, roller coating method, casting method, slot coating method, and strip coating method; further, the printing method includes, but is not limited to: inkjet printing.

[0143] This application also provides a display device, which includes the light-emitting device described above or the light-emitting device prepared by the method described above.

[0144] In some implementations, the display device can be any electronic product with display functionality, including but not limited to smartphones, tablets, laptops, digital cameras, digital camcorders, smart wearable devices, smart weighing scales, in-vehicle displays, televisions, or e-book readers. Among these, smart wearable devices can be, for example, smart bracelets, smartwatches, or virtual reality devices.

[0145] The above solution will be further explained below with reference to specific embodiments. Optional embodiments of this application are detailed below:

[0146] Example 1:

[0147] This application provides a method for fabricating a light-emitting device, the method of which is as follows:

[0148] Step 1: Provide an anode, which is an ITO glass substrate with a thickness of 100nm.

[0149] Step 2: Spin-coat a first mixed solution consisting of a doped or undoped first metal oxide solution and an organic ammonium salt solution onto the anode to obtain a first thin film, and dry the first thin film at 100°C for 10 min to obtain a first carrier functional layer with a thickness of 10 nm.

[0150] The first metal oxide solution, whether doped or undoped, is a molybdenum oxide solution, and the solvent is butanol; the organic ammonium salt solution is a benzene-1,3,5-trimethyltrimethylamine chloride solution, and the solvent in the benzene-1,3,5-trimethyltrimethylamine chloride solution is methanol; in the first mixed solution, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride is 1:0.15.

[0151] Step 3: A light-emitting layer is formed on the first carrier functional layer by inkjet printing. The light-emitting layer is made of CdSe / ZnS material and has a thickness of 30nm.

[0152] Step 4: Spin-coat the light-emitting layer with a second mixed solution consisting of an organic ammonium salt solution and a methanol solvent to obtain a second thin film, and dry the second thin film at 100°C for 10 min to obtain an auxiliary layer with a thickness of 2 nm.

[0153] The organic ammonium salt solution is a benzene-1,3,5-trimethyltrimethylamine chloride solution, and the solvent in the benzene-1,3,5-trimethyltrimethylamine chloride solution is methanol; in the second mixed solution, the mass percentage of benzene-1,3,5-trimethyltrimethylamine chloride is 10%.

[0154] Step 5: Form a second carrier functional layer of zinc oxide on the auxiliary layer by inkjet printing. The thickness of the second carrier functional layer is 30 nm.

[0155] Step 6: A cathode is formed on the second carrier functional layer of zinc oxide by inkjet printing to obtain a light-emitting device. The cathode is made of Al material and has a thickness of 30 nm.

[0156] Example 2

[0157] The difference between Example 2 and Example 1 is:

[0158] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0.001.

[0159] Example 3

[0160] The difference between Example 3 and Example 1 is:

[0161] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0.3.

[0162] Example 4

[0163] The difference between Example 4 and Example 1 is:

[0164] In step 2, the thickness of the first carrier functional layer is 1 nm.

[0165] Example 5

[0166] The difference between Example 5 and Example 1 is:

[0167] In step 2, the thickness of the first carrier functional layer is 50 nm.

[0168] Example 6

[0169] The difference between Example 6 and Example 1 is:

[0170] In step 4, the thickness of the auxiliary layer is 0.1 nm.

[0171] Example 7

[0172] The difference between Example 7 and Example 1 is:

[0173] In step 4, the thickness of the auxiliary layer is 20 nm.

[0174] Example 8

[0175] The difference between Example 8 and Example 1 is:

[0176] In step 4, the mass percentage of benzene-1,3,5-trimethyltrimethylamine chloride in the second mixed solution is 1%.

[0177] Example 9

[0178] The difference between Example 9 and Example 1 is:

[0179] In step 4, the mass percentage of benzene-1,3,5-trimethyltrimethylamine chloride in the second mixed solution is 50%.

[0180] Example 10

[0181] The difference between Example 10 and Example 1 is:

[0182] In step 2, the doped or undoped first metal oxide solution is a tungsten trioxide solution, and the solvent for the tungsten trioxide solution is butanol.

[0183] Example 11

[0184] The difference between Example 11 and Example 1 is:

[0185] In step 2, the organic ammonium salt solution is a 1,4-phenylenediamine ammonium bromide solution, and the solvent for the 1,4-phenylenediamine ammonium bromide solution is ethanol.

[0186] Example 12

[0187] The difference between Example 12 and Example 1 is:

[0188] In step 4, the organic ammonium salt solution is a (1-ethylbutyl)amine solution, and the solvent for the (1-ethylbutyl)amine solution is DMF.

[0189] Example 13

[0190] The difference between Example 13 and Example 1 is:

[0191] In step 5, the material of the second carrier functional layer is tin oxide.

[0192] Comparative Example 1

[0193] The difference from Example 1 is as follows:

[0194] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0.

[0195] Comparative Example 2

[0196] The difference from Example 1 is as follows:

[0197] Step 4 was not performed;

[0198] The corresponding change in step 5 is: forming a second carrier functional layer of zinc oxide on the light-emitting layer by inkjet printing.

[0199] Comparative Example 3

[0200] The difference from Example 1 is as follows:

[0201] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0, and the operation in step 4 is not performed.

[0202] The corresponding change in step 5 is: forming a second carrier functional layer of zinc oxide on the light-emitting layer by inkjet printing.

[0203] Comparative Example 4

[0204] The difference from Example 1 is as follows:

[0205] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0.5.

[0206] Comparative Example 5

[0207] The difference from Example 1 is as follows:

[0208] In step 2, the mass ratio of molybdenum oxide to benzene-1,3,5-trimethyltrimethylamine chloride in the first mixed solution is 1:0.0005.

[0209] Comparative Example 6

[0210] The difference from Example 1 is as follows:

[0211] In step 4, the thickness of the auxiliary layer is 50 nm.

[0212] The light-emitting devices prepared in Examples 1 to 13 and Comparative Examples 1 to 6 were subjected to current efficiency and lifespan tests.

[0213] The current efficiency test method is as follows: set the light-emitting area to 2mm×2mm=4mm2, and intermittently collect the brightness value of the light-emitting device within the range of driving voltage from 0V to 8V. The initial brightness voltage value is 0.5V, and it is collected once every 0.2V. The brightness value collected each time is divided by the corresponding current density to obtain the current efficiency of the light-emitting device under the sampling condition.

[0214] The lifespan test method is as follows: Under constant current (2mA) drive, a 128-channel QLED lifespan test system is used to perform electroluminescence lifespan analysis on each light-emitting device, record the time (T95,h) required for each light-emitting device to decay from maximum brightness to 95%, and calculate the time (T95@1000nit,h) required for each light-emitting device to decay from 100% brightness to 95% brightness at 1000nit using the decay fitting formula.

[0215] The test results are shown in Table 1.

[0216] Table 1

[0217]

[0218]

[0219] As shown in Table 1, compared to Comparative Examples 1 and 3, the materials of the first carrier functional layer in Examples 1-13, including organic ammonium salts and doped or undoped first metal oxides, significantly increase the current efficiency and lifetime of the devices. This demonstrates that the first carrier functional layer proposed in this invention can effectively improve the luminous efficiency and lifetime of the light-emitting device. The reason may be that the ammonium ions of the organic ammonium salt in the first carrier functional layer of the light-emitting devices in Examples 1-13 can form strong hydrogen bonds with the oxygen ions in the first metal oxide. This hydrogen bond interaction can fix the oxygen ions generated by the first metal oxide, suppress the movement of impurity oxygen ions, reduce oxygen vacancy defects in the first metal oxide, improve the hole mobility and hole injection efficiency of the first carrier functional layer, improve the injection balance of holes and electrons in the light-emitting layer, and thus improve the luminous efficiency and lifetime of the light-emitting device.

[0220] Based on the test results of Examples 1-13 and Comparative Examples 2 and 3 of the light-emitting devices, it can be seen that by setting an auxiliary layer on the side of the second carrier functional layer close to the light-emitting layer, the auxiliary layer can regulate the transmission efficiency of electrons from the second carrier functional layer to the light-emitting layer. At the same time, the ammonium ions at the end of the organic ammonium salt in the auxiliary layer interact with the oxygen in the second metal oxide, causing the charge on the ammonium ions to transfer to the second metal oxide, thereby increasing the conduction band energy level and electron injection barrier of the second carrier functional layer, reducing the injection of electrons from the second electrode to the second carrier functional layer, and avoiding excessive and rapid transmission of electrons from the second electrode to the second carrier functional layer. This can further ensure the injection balance of holes and electrons in the light-emitting layer, and improve the luminous efficiency and lifespan of the light-emitting device.

[0221] Based on the test results of Examples 1-13 and Comparative Examples 4 and 5 of the light-emitting devices, it can be seen that by appropriately setting the mass ratio of the first metal oxide to the organic ammonium salt in the first carrier functional layer, the hole mobility and hole injection efficiency of the first carrier functional layer can be effectively improved, the injection balance of holes and electrons in the light-emitting layer can be improved, and the luminous efficiency and service life of the light-emitting device can be increased.

[0222] Based on the test results of Examples 1-13 and Comparative Example 6 of the light-emitting device, it can be seen that by appropriately setting the thickness of the auxiliary layer, the electronic control effect of the auxiliary layer can be further guaranteed, the injection balance of holes and electrons in the light-emitting layer can be improved, and the luminous efficiency and service life of the light-emitting device can be increased.

[0223] Obviously, the embodiments described above are only some embodiments of this application, not all embodiments. The accompanying drawings show preferred embodiments of this application, but do not limit the patent scope of this application. This application can be implemented in many different forms; rather, the purpose of providing these embodiments is to provide a more thorough and comprehensive understanding of the disclosure of this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing specific embodiments, or make equivalent substitutions for some of the technical features. Any equivalent structures made using the content of this application's specification and drawings, directly or indirectly applied to other related technical fields, are similarly within the scope of patent protection of this application.

Claims

1. A light-emitting device, characterized in that, The light-emitting device includes a first electrode, a first carrier functional layer, a light-emitting layer, and a second electrode stacked sequentially. The material of the first carrier functional layer includes an organic ammonium salt and a first metal oxide.

2. The light-emitting device according to claim 1, characterized in that, The first metal oxide comprises one or more of the following: doped or undoped tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, aluminum zinc oxide, manganese zinc oxide, tin zinc oxide, lithium zinc oxide, and indium tin oxide. The doped element in the doped oxide comprises one or more of the following: Li, Ca, Ga, Mg, Ce, Al, and Zn; and / or The average thickness of the first carrier functional layer is 1 nm to 50 nm, optionally, the average thickness of the first carrier functional layer is 5 nm to 30 nm; and / or In the first carrier functional layer, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.001-0.3), optionally, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.01-0.2); and / or The cations in the organic ammonium salt are bonded to the first metal oxide via hydrogen bonds.

3. The light-emitting device according to claim 1, characterized in that, The structural formula of the organic ammonium salt is shown in Formula I: wherein X - is an anion selected from one of Cl - , Br - , and I - . The substituent R is selected from hydrogen, C1-C25 straight-chain alkyl, C2-C25 branched alkyl, C3-C25 cycloalkyl, substituted or unsubstituted aromatic group having 6 to 20 ring atoms, and substituted or unsubstituted heteroaryl group having 6 to 20 ring atoms. The substituted substituent is selected from halogen, hydroxyl, carboxyl, nitro, sulfonic acid, aldehyde, mercapto, cyano, ether alkyl, carbonyl alkyl. The heteroatom in the heteroaryl group is N, S, O, P, Si, or B, and the number of heteroatoms is 1 to 20.

4. The light-emitting device according to claim 3, characterized in that, The organic ammonium salt is selected from any of the following structures:

5. The light-emitting device according to any one of claims 1 to 4, characterized in that, The light-emitting device further includes an auxiliary layer and a second charge carrier functional layer, which are located between the light-emitting layer and the second electrode. The auxiliary layer is closer to the light-emitting layer than the second charge carrier functional layer, and the material of the auxiliary layer includes the organic ammonium salt.

6. The light-emitting device according to claim 5, characterized in that, The material of the second carrier functional layer includes a second metal oxide.

7. The light-emitting device according to claim 6, characterized in that, The average thickness of the second carrier functional layer is 1 nm to 50 nm; and / or The average thickness of the auxiliary layer is 0.1 nm to 20 nm; and / or The second metal oxide is selected from one or more of the following: doped or undoped zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium; and / or The first electrode and the second electrode are each selected from one or more of a metal electrode, a silicon-carbon electrode, a doped or undoped metal oxide electrode, and a composite electrode; wherein, the material of the metal electrode is selected from at least one of Al, Ag, Cu, Mo, Au, Ba, Ca, and Mg; the material of the silicon-carbon electrode is selected from at least one of silicon, graphite, carbon nanotubes, graphene, and carbon fiber; the material of the doped or undoped metal oxide electrode is selected from at least one of ITO, FTO, ATO, AZO, GZO, IZO, MZO, and AMO; the material of the composite electrode is selected from at least one of 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, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2; and / or The material of the light-emitting layer includes at least one of organic light-emitting materials, single-structure quantum dots, and core-shell structure quantum dots. The organic light-emitting material is selected from one or more of the following: 4,4'-bis(N-carbazole)-1,1'-biphenyl:tris[2-(p-tolyl)pyridinium(II), 4,4',4”-tris(carbazole-9-yl)triphenylamine:tris[2-(p-tolyl)pyridinium(II), diaromatic anthracene 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, thermally activated delayed materials, polymers containing BN covalent bonds, hybrid localized charge transfer excited-state materials, and excitocomplex light-emitting materials. The shell of the core-shell structure quantum dot includes one or more layers.The material of the single-structure quantum dot, the core material of the core-shell structure quantum dot, and the shell material of the core-shell structure quantum dot are each selected from at least one of group II-VI compounds, group IV-VI compounds, group III-V compounds, and group I-III-VI compounds. Group I-VI compounds include 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, and CdZn. One or more of the following compounds: SeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; and group IV-VI compounds including SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, and S. One or more of nPbSSe, SnPbSeTe, and SnPbSTe; III-V compounds including 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; I-III-VI compounds including at least one of CuInS2, CuInSe2, and AgInS2; and / or; The first carrier functional layer is a hole functional layer. The material of the hole functional layer includes an organic ammonium salt and a first metal oxide. The first metal oxide includes one or more of the following: doped or undoped tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide. The doped element of the doped oxide includes one or more of the following: Li, Ca, Ga, Mg, Ce, Al, and Zn; and / or The second carrier functional layer is an electronic functional layer. The material of the electronic functional layer includes a second metal oxide. The second metal oxide is selected from one or more of the following: zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide, and the doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

8. A method for fabricating a light-emitting device, characterized in that, The preparation steps include the following: Provide the first electrode; A first carrier functional layer is formed on the first electrode; A light-emitting layer is disposed on the first carrier functional layer; A second electrode is disposed on the light-emitting layer to obtain the light-emitting device; or, Provide a second electrode, A light-emitting layer is disposed on the second electrode; A first carrier functional layer is formed on the light-emitting layer; A first electrode is disposed on the first carrier functional layer to obtain the light-emitting device; The material of the first carrier functional layer includes an organic ammonium salt and a first metal oxide.

9. The preparation method according to claim 8, characterized in that, The first carrier functional layer is formed in the following manner: A first mixed solution is provided, the first mixed solution comprising a doped or undoped first metal oxide solution and an organic ammonium salt solution; The first mixed solution is used to form a first thin film on the first electrode or the light-emitting layer; as well as The first thin film is dried to obtain the first carrier functional layer.

10. The preparation method according to claim 9, characterized in that, The method for preparing the first mixed solution includes the following steps: The doped or undoped first metal oxide solution is mixed with the organic ammonium salt solution to obtain the first mixed solution; The solvent in the doped or undoped first metal oxide solution includes at least one of methanol, ethanol, n-butanol, n-pentanol, n-hexanol, n-heptanol, 2-methoxyethanol, DMF, DMSO, and 2-ethoxyethanol; and / or In the doped or undoped first metal oxide, the first metal oxide includes one or more of tungsten oxide, nickel oxide, molybdenum oxide, zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide; and the doping element of the doped oxide includes one or more of Li, Ca, Ga, Mg, Ce, Al, and Zn; and / or The solvent in the organic ammonium salt solution includes at least one selected from methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol; and / or The structural formula of the organic ammonium salt is shown in Formula I: Among them, X - It is an anion, selected from Cl. - ,Br - and I - One of them; The substituent R is selected from hydrogen, a C1-C25 straight-chain alkyl group, a C2-C25 branched-chain alkyl group, a C3-C25 cycloalkyl group, a substituted or unsubstituted aromatic group having 6 to 20 ring atoms, or a substituted or unsubstituted heteroaryl group having 6 to 20 ring atoms. The substituted substituent is selected from halogen, hydroxyl, carboxyl, nitro, sulfonic acid, aldehyde, mercapto, cyano, ether alkyl, and carbonyl alkyl. The heteroatom in the heteroaryl group is N, S, O, P, Si, or B, and the number of heteroatoms is 1-20. The organic ammonium salt is selected from any of the following structures: and / or The mixing temperature of the first mixed solution is 25℃~150℃, optionally, the mixing temperature of the first mixed solution is 40℃~120℃, optionally, the mixing temperature of the first mixed solution is 60℃~70℃; and / or, the stirring time of the first mixed solution is 1min~240min, optionally, the stirring time of the first mixed solution is 10min~120min, optionally, the stirring time of the first mixed solution is 30min~60min; and / or In the first mixed solution, the mass ratio of the doped or undoped first metal oxide to the organic ammonium salt is 1:(0.001–0.3), optionally, the mass ratio of the first metal oxide to the organic ammonium salt is 1:(0.01–0.2); and / or In the step of drying the first film, the drying temperature is 40℃~150℃, optionally, the drying temperature is 70℃~120℃, optionally, the drying temperature is 80℃~100℃; and / or, the drying time is 1min~60min, optionally, the drying time is 2min~45min, optionally, the drying time is 10min~30min.

11. The preparation method according to any one of claims 8 to 10, characterized in that, Before the step of setting the second electrode on the light-emitting layer, the following steps are also included: An auxiliary layer is disposed on the light-emitting layer; A second carrier functional layer is provided on the auxiliary layer; or, The step of forming the light-emitting layer on the second electrode is preceded by the following steps: A second carrier functional layer is formed on the second electrode; An auxiliary layer is provided on the second carrier functional layer; The auxiliary layer is made of the organic ammonium salt; and / or The material of the second carrier functional layer includes a second metal oxide, which is selected from one or more of the following: zinc oxide, barium oxide, aluminum oxide, nickel oxide, titanium oxide, tin oxide, tantalum oxide, zirconium oxide, nickel oxide, lithium titanium oxide, zinc aluminum oxide, zinc manganese oxide, zinc tin oxide, zinc lithium oxide, and indium tin oxide, and the doped element includes at least one of aluminum, magnesium, lithium, manganese, yttrium, lanthanum, copper, nickel, zirconium, cerium, and gadolinium.

12. The preparation method according to claim 11, characterized in that, The auxiliary layer is formed in the following manner: A second mixed solution is provided, the second mixed solution comprising an organic ammonium salt solution and a first solvent; The second mixed solution is used to form a second thin film on the light-emitting layer or the second charge-carrier functional layer; and The second film is dried to obtain the auxiliary layer.

13. The preparation method according to claim 12, characterized in that, The method for preparing the second mixed solution includes the following steps: The organic ammonium salt solution is mixed with the first solvent to obtain the second mixed solution; Wherein, the first solvent includes at least one selected from chlorobenzene, methanol, ethanol, propanol, butanol, pentanol, hexanol, heptanol, octanol, DMF, DMSO, and cyclohexanol; and / or In the second mixed solution, the organic ammonium salt has a mass percentage of 1% to 50%, optionally 5% to 30%, optionally 10% to 20%; and / or The mixing temperature of the second mixed solution is 25℃~150℃, optionally, the mixing temperature of the second mixed solution is 40℃~120℃, optionally, the mixing temperature of the second mixed solution is 60℃~70℃; and / or, the stirring time of the second mixed solution is 1min~240min, optionally, the stirring time of the second mixed solution is 10min~120min, optionally, the stirring time of the second mixed solution is 30min~60min; and / or In the step of drying the second film, the drying temperature is 25℃~120℃, optionally 50℃~100℃, optionally 60℃~80℃; and / or the drying time is 0.5min~60min, optionally 2min~40min, optionally 10min~30min.

14. A display device comprising a light-emitting device as described in any one of claims 1 to 7 or a light-emitting device prepared by the method described in any one of claims 8 to 13.

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