Composite material, light-emitting device, preparation method of light-emitting device and display device

Abstract

The invention discloses a composite material, a light-emitting device, a preparation method of the light-emitting device and a display device. The composite material comprises nanoparticles and polypeptide. According to the composite material disclosed by the invention, the polypeptide is added into the nanoparticles, and the polypeptide can be used for passivating defects on the surfaces of the nanoparticles and fixing the nanoparticles, so that the problem of ion migration of the nanoparticles is solved, and the thermal stability of the composite material is improved.

Description

Technical Field

[0001] This application relates to the field of display technologies, and particularly to a composite material, a light-emitting device, a preparation method thereof, and a display device. Background Art

[0002] Nanomaterials refer to materials in which at least one dimension is in the nanoscale range (1 nm to 100 nm) in three-dimensional space or materials composed of them as basic units. Since nanomaterials are composed of tiny units equivalent to molecular size or even atomic size, nanomaterials have some special physical or chemical properties different from other material materials formed by the same chemical elements, such as mechanical properties, electrical properties, magnetic properties, thermal properties, etc. These properties enable nanomaterials to be applied in various rapidly developing scientific and technological fields.

[0003] There is obvious ion migration in the nanoparticles of nanomaterials under the action of an electric field, and their stability needs to be further improved. Summary of the Invention

[0004] In view of this, this application provides a composite material, aiming to improve the ion migration problem existing in the nanoparticles of existing light-emitting devices.

[0005] An embodiment of this application is implemented as follows. A composite material includes nanoparticles and polypeptides.

[0006] Optionally, in some embodiments of this application, the nanoparticles include one or more of N-type inorganic semiconductor particles and quantum dots; and / or

[0007] The polypeptides include at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine.

[0008] Optionally, in some embodiments of this application, the mass ratio of the quantum dots to the polypeptides is (5 - 50) : 1; and / or

[0009] The mass ratio of the N-type inorganic semiconductor particles to the polypeptides is (2 - 50) : 1; and / or

[0010] The average particle size of the quantum dots is 5 - 15 nm; and / or

[0011] The average particle size of the N-type inorganic semiconductor particles is 2 - 10 nm; and / or

[0012] The N-type inorganic semiconductor particles include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3, and the dopants in the doped metal oxides include one or several of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, and Sn. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, and CdS. The IIIA-VA group semiconductor materials include one or more of InP and GaP. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS and CuGaS; and / or

[0013] The quantum dots include one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite quantum dots; the materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots include one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the shell layer of the core-shell structure quantum dots is one or more layers; the II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; the IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group 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; the I-III-VI group compounds include one or more of CuInS2, CuInSe2, and AgInS2;The quantum dots with core-shell structure include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS; the perovskite quantum dots include doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the structural general formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; the structural general formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation, including CH3(CH2) n-2 NH 3+ or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them.

[0014] Correspondingly, the present application also provides a light-emitting device

[0015] Comprising a first electrode, a functional layer, and a second electrode which are stacked, the functional layer includes a light-emitting layer, and the material of the light-emitting layer includes quantum dots and a first polypeptide; and / or

[0016] The functional layer includes an electron functional layer, and the material of the electron functional layer includes N-type inorganic semiconductor particles and a second polypeptide.

[0017] Optionally, in some embodiments of the present application, the mass ratio of the quantum dots to the first oligopeptide is (5 - 50):1; and / or

[0018] The mass ratio of the N-type inorganic semiconductor particles to the second oligopeptide is (2 - 50):1; and / or

[0019] The thickness of the light-emitting layer is 10 - 30 nm; and / or

[0020] The thickness of the electron functional layer is 20 - 60 nm; and / or

[0021] The average particle size of the quantum dots is 5 - 15 nm; and / or

[0022] The average particle size of the N-type inorganic semiconductor particles is 2 - 10 nm.

[0023] Optionally, in some embodiments of the present application, the first polypeptide and the second polypeptide each independently include at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or several of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or

[0024] The quantum dots include one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite-type quantum dots; the materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots include one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the shell of the core-shell structure quantum dots is one or more layers; the II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; the IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group 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; the I-III-VI group compounds include one or more of CuInS2, CuInSe2, and AgInS2;The quantum dots with core-shell structure include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS, and InP / ZnSe / ZnS; the perovskite quantum dots include doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the structural general formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; the structural general formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation, including CH3(CH2) n-2 NH 3+ or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; and / or

[0025] The electronic functional layer includes one or more of an electron injection layer and an electron transport layer. The material of the electronic functional layer includes one or more of an inorganic electronic functional material and an organic electronic functional material. The N-type inorganic semiconductor particles include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3. The dopants in the doped metal oxides include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, and Sn. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, and CdS. The IIIA-VA group semiconductor materials include one or more of InP and GaP. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS and CuGaS. The organic electronic functional materials include one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds; and / or

[0026] The materials of the first electrode and the second electrode each independently include one or more of metals, carbon materials, and metal oxides. The metals include one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg. The carbon materials include one or more of graphite, carbon nanotubes, graphene, and carbon fibers. The metal oxides include a metal oxide electrode or a composite electrode with a metal sandwiched between doped or undoped transparent metal oxides. The materials of the metal oxide electrode include one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3, and AMO. The composite electrodes include one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2; and / or

[0027] The light-emitting device further includes a hole functional layer disposed between the light-emitting layer and the first electrode or the second electrode. The hole functional layer includes one or more of a hole injection layer and a hole transport layer. The material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green light-emitting material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,One or more of N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose, tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides, and metal nitrides, wherein the metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles each independently include one or more of MoO3, WO3, NiO, CrO3, CuO, and V2O5, the doping elements in the second doped metal oxide particles include one or more of Mo, W, Ni, Cr, Cu, and V, the metal sulfides include one or more of CuS, MoS3, and WS3, the metal selenides include one or more of MoSe3 and WSe3, and the metal nitrides include p-type gallium nitride.,

[0028] Correspondingly, the present application further provides a method for preparing a light-emitting device, comprising the following steps:

[0029] Providing a light-emitting device preform, the light-emitting device preform including a first electrode;

[0030] Providing a light-emitting material and / or an electron-functional material, and disposing the light-emitting material and / or the electron-functional material on the light-emitting device preform to form a light-emitting layer and / or an electron-functional layer, the light-emitting material including quantum dots and a first oligopeptide, and the electron-functional material including N-type inorganic semiconductor particles and a second oligopeptide;

[0031] Performing a heat treatment on the light-emitting device preform provided with the light-emitting layer and / or the electron-functional layer to cause a cross-linking reaction of the first oligopeptide and / or the second oligopeptide to form a polypeptide;

[0032] Forming a second electrode on the light-emitting layer or the electron-functional layer to obtain a light-emitting device.

[0033] Optionally, in some embodiments of the present application, the forming of the light-emitting layer includes: providing quantum dots, a first oligopeptide, and a first solvent, mixing to obtain a first mixed solution, and disposing the first mixed solution on the light-emitting device preform to form a light-emitting layer; and / or

[0034] The forming of the electron-functional layer includes: providing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mixing to obtain a second mixed solution, and disposing the second mixed solution on the light-emitting device preform, and evacuating to form an electron-functional layer.

[0035] Optionally, in some embodiments of the present application, the mixing to obtain the second mixed solution further includes:

[0036] After mixing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, irradiate with ultraviolet light to obtain a second mixed solution; and / or

[0037] The mixing to obtain the first mixed solution further includes:

[0038] After mixing quantum dots, a first oligopeptide, and a first solvent, irradiate with ultraviolet light to obtain a first mixed solution.

[0039] Optionally, in some embodiments of the present application, the first oligopeptide and the second oligopeptide each independently include at least one of a dehydration condensate of 2 to 10 amino acids and a derivative of a dehydration condensate of 2 to 10 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or

[0040] The polypeptide includes at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or

[0041] The mass ratio of the quantum dots to the first oligopeptide is (5 - 50):1; and / or

[0042] The mass ratio of the N-type inorganic semiconductor particles to the second oligopeptide is (2 - 50):1; and / or

[0043] The thickness of the light-emitting layer is 10 - 30 nm; and / or

[0044] The thickness of the electron functional layer is 20 - 60 nm; and / or

[0045] The thickness of the polypeptide layer formed by crosslinking the third oligopeptide is 1 - 5 nm; and / or

[0046] The mass concentration of the first mixed solution is 0.24 - 2.4 mg / ml; and / or

[0047] The first solvent and the second solvent each independently include one or more of n-octane, dimethylformamide, ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol; and / or

[0048] The mass concentration of the second mixed solution is 0.6 - 15 mg / ml; and / or

[0049] The temperature of the heat treatment is 40 - 120 °C, and the time of the heat treatment is 10 - 120 min; and / or

[0050] The wavelength of the ultraviolet light is 365 - 430 nm, and the time of the ultraviolet light irradiation is 5 - 120 s.

[0051] Optionally, in some embodiments of the present application, the first electrode is an anode, the second electrode is a cathode, and the light-emitting device preform includes a first electrode and a hole functional layer; or

[0052] The first electrode is a cathode, the second electrode is an anode, and forming the second electrode on the light-emitting layer or the electron functional layer includes forming a hole functional layer and the second electrode on the light-emitting layer or the electron functional layer to obtain a light-emitting device.

[0053] Correspondingly, the present application further provides a display device, and the display device includes the above-mentioned light-emitting device.

[0054] By adding polypeptides to the nanoparticles in the composite material of the present application, the defects on the surface of the nanoparticles can be passivated by the polypeptides, and the nanoparticles can be fixed, thereby solving the problem of ion migration existing in the nanoparticles, and thus improving the thermal stability of the composite material. BRIEF DESCRIPTION OF THE DRAWINGS

[0055] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0056] Figure 1 is a schematic structural diagram of a light-emitting device provided by an embodiment of the present application;

[0057] Figure 2 is a flowchart of a preparation method of a light-emitting device provided by an embodiment of the present application.

[0058] Reference Signs:

[0059] Light-emitting device 100; first electrode 10; hole functional layer 20; light-emitting layer 30; electron functional layer 40; second electrode 50. Detailed implementation manners

[0060] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application. In addition, it should be understood that the specific implementation manners described herein are only for explaining and illustrating the present application, and are not used to limit the present application.

[0061] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this invention belongs. The terms used in the description of the present invention herein are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0062] In the present application, unless otherwise stated, the orientation terms such as "upper" and "lower" generally refer to the upper and lower in the actual use or working state of the device, specifically the drawing direction in the accompanying drawings; while "inner" and "outer" refer to the outline of the device. In addition, in the description of the present application, the term "comprising" means "including but not limited to". The terms first, second, third, etc. are only used as labels and do not impose numerical requirements or establish an order.

[0063] In the present application, "and / or" describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. Wherein A and B can be singular or plural.

[0064] In the present application, "at least one" means one or more, and "a plurality" means two or more. "One or more", "at least one of the following (items)" or similar expressions refer to any combination of these items, including any combination of single (item) or plural items (items). For example, "at least one of (item) a, b, or c", or, "at least one of (item) a, b, and c" can both represent: a, b, c, a - b (i.e., a and b), a - c, b - c, or a - b - c, where a, b, and c can be single or multiple respectively.

[0065] In this application, when forming another layer "on" a certain layer, the so-called "on" is a broad concept, which can mean that the formed another layer is adjacent to the certain layer, or there are other spacer structure layers between the another layer and the certain layer. For example, when forming a second electrode "on" the first carrier functional layer, the so-called "on" can mean that the formed second electrode is adjacent to the first carrier functional layer, or there are other spacer structure layers between the second electrode and the first carrier functional layer, such as a light-emitting layer.

[0066] The 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 only for convenience and brevity, and should not be construed as a rigid limitation on the scope of this application; therefore, it should be considered that the description of the said range has specifically disclosed all possible sub-ranges and the individual values within that range. For example, it should be considered that the description of the range from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and the individual numbers within the said range, such as 1, 2, 3, 4, 5, and 6, and this applies regardless of the range. Additionally, whenever a numerical range is indicated herein, it means including any cited numbers (fractions or integers) within the indicated range.

[0067] Term definitions and explanations:

[0068] Amino acids are involved in this application. For ease of understanding, the following comparison explanations are made for the three-letter abbreviations and symbols of amino acids: Glycine (Gly), Alanine (Ala), Valine (Val), Leucine (Leu), Isoleucine (Ile), Methionine (Met), Proline (Pro), Phenylalanine

[0069]

[0070] (Phenylalanine, Phe, F), Tyrosine (Tyr, Y), Tryptophan (Trp, W), Serine (Ser, S), Threonine (Thr, T), Cysteine (Cys, C), Asparagine (Asn, N), Glutamine (Gln, Q), Aspartic acid (Asp, D), Glutamic acid (Glu, E), Lysine (Lys, K), Arginine (Arg, R), Histidine (His, H), Selenocysteine (Sec, B), Pyrrolysine (Pyl O, U). Exemplarily, the dehydration condensate of amino acids, GRGDS, represents an oligopeptide formed by the sequential condensation of one glycine, one arginine, one glycine, one aspartic acid, and one serine. Its structural formula is as follows:

[0071] Derivatives of the dehydration condensate of amino acids refer to more complex products derived by replacing hydrogen atoms or atomic groups in the dehydration condensate of amino acids with other atoms or atomic groups. Exemplarily, the derivative of the dehydration condensate of amino acids, GRGDS-NH2, represents an oligopeptide formed by the sequential condensation of one glycine, one arginine, one glycine, one aspartic acid, and one serine, and the -OH in the terminal -COOH is replaced by an amino group -NH2. Its structural formula is as follows:

[0072]

[0073] The technical solution of this application is as follows:

[0074] In a first aspect, please refer to Figure 1 , an embodiment of this application provides a light-emitting device 100 including a first electrode 10, a functional layer, and a second electrode 50 arranged in a stacked manner. The functional layer includes a light-emitting layer 30, and the material of the light-emitting layer 30 includes quantum dots and a first polypeptide; and / or

[0075] The functional layer includes an electron functional layer 40, and the material of the electron functional layer 40 includes N-type inorganic semiconductor particles and a second polypeptide.

[0076] The light-emitting device 100 provided by the present application adds polypeptides to the light-emitting layer 30 and / or the electron functional layer 40. Groups such as peptide bonds, mercapto groups, and aromatic groups of the polypeptides will capture free small molecule groups remaining in the light-emitting device 100, thereby improving the efficiency and thermal stability of the device; at the same time, groups such as peptide bonds and aromatic groups in the polypeptides are used as various Lewis acid-base passivations for various defects in the quantum dots, thereby improving the light-emitting efficiency of the device; the polypeptide chain can fix nanoparticles and free small molecules remaining in the device, thereby avoiding the problem of ion migration during device operation, and further improving the efficiency and thermal stability of the device.

[0077] In some embodiments, each of the first polypeptide and the second polypeptide independently includes at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine.

[0078] In some embodiments, the mass ratio of the quantum dots to the first polypeptide is (5 - 50):1, for example, it can be 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, etc. In this way, the polypeptide can play a good role in fixing nanoparticles and at the same time has appropriate charge transport ability.

[0079] In some embodiments, the mass ratio of the N-type inorganic semiconductor particles to the second polypeptide is (2 - 50):1, for example, it can be 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, etc. In this way, the polypeptide can passivate defects well, construct a network structure to fix nanoparticles, and at the same time has appropriate charge transport ability.

[0080] In some embodiments, the thickness of the light-emitting layer 30 is 10 - 30 nm.

[0081] In some embodiments, the thickness of the electron functional layer 40 is 20 - 60 nm.

[0082] In some embodiments, the material of the light-emitting layer 30 includes one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite-type quantum dots. The first quantum dot and the second quantum dot independently include the materials of single-structure quantum dots, the core materials of core-shell structure quantum dots, and the shell materials of core-shell structure quantum dots, respectively, and can be selected from, but not limited to, the single-structure quantum dots selected from one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds. The II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe. The IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe. The III-V group 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. The I-III-VI group compounds include one or more of CuInS2, CuInSe2, and AgInS2.

[0083] As an example, the quantum dots of the core-shell structure include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS, and InP / ZnSe / ZnS. In the expressions such as CdSe / ZnS above, " / " means that the material after " / " (as the shell layer) coats the material before " / " (as the core layer).

[0084] The perovskite quantum dots include doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors. The general structural formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation selected from Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ one or more of them, and X is a halogen anion selected from Cl - , Br - , I - one or more of them. The general structural formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation selected from CH3(CH2) n-2 NH3 + or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation selected from Pb 2+ , Sn 2+ , Cu 2+ , Ni 2+ , Cd 2+ , Cr 2+ , Mn 2+ , Co 2+ , Fe 2+ , Ge 2+ , Yb 2+ , Eu 2+ one or more of them, and X is a halogen anion selected from Cl - , Br - , I - one or more of them.

[0085] In some embodiments, the average particle size of the quantum dots is 5 - 15 nm.

[0086] In some embodiments, the average particle size of the N-type inorganic semiconductor particles is 2 - 10 nm.

[0087] In some embodiments, the electronic functional layer 40 includes one or more of an electron injection layer and an electron transport layer.

[0088] In some embodiments, the N-type inorganic semiconductor particles include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5; the metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3, and the dopants in the doped metal oxides include one or several of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, and Sn; the IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, and CdS; the IIIA-VA group semiconductor materials include one or more of InP and GaP; the IB-IIIA-VIA group semiconductor materials include one or more of CuInS and CuGaS; the organic electronic functional materials include one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds.

[0089] In some embodiments, the material of the electronic functional layer 40 includes one or more of inorganic electronic functional materials and organic electronic functional materials. The inorganic electronic functional materials include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5. The metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, Al2O3, and the dopants in the doped metal oxides include one or several of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, Sn. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, CdS. The IIIA-VA group semiconductor materials include one or more of InP, GaP. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS, CuGaS. The organic electronic functional materials include one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds.

[0090] In some embodiments, the first electrode 10 and the second electrode 50 each independently include one or several of metals, carbon materials, and metal oxides. The metals include one or several of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg. The carbon materials include one or several of graphite, carbon nanotubes, graphene, and carbon fibers. The metal oxides include metal oxide electrodes or composite electrodes with a metal sandwiched between doped or undoped transparent metal oxides. The materials of the metal oxide electrodes include one or several of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3, and AMO. The composite electrodes include one or several of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2. Herein, " / " represents a laminated structure. For example, AZO / Ag / AZO represents a composite electrode including an AZO layer, an Ag layer, and an AZO layer laminated in sequence.

[0091] In some embodiments, the light-emitting device 100 further includes a hole functional layer 20.

[0092] In some embodiments, the hole functional layer 20 includes one or several of a hole injection layer and a hole transport layer.

[0093] In some embodiments, the material of the hole functional layer 20 includes one or more of 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green light-emitting material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose, and tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides, and metal nitrides. The metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles each independently include one or more of MoO3, WO3, NiO, CrO3, CuO, V2O5. The doping elements in the second doped metal oxide particles include one or more of Mo, W, Ni, Cr, Cu, V. The metal sulfides include one or more of CuS, MoS3, WS3. The metal selenides include one or more of MoSe3, WSe3. The metal nitrides include p-type gallium nitride.

[0094] In a second aspect, please refer to Figure 2 , an embodiment of the present application further provides a method for manufacturing a light-emitting device 100, including:

[0095] S11. Provide a light-emitting device preform, where the light-emitting device preform includes a first electrode 10;

[0096] S12. Provide quantum dots, a first oligopeptide, and a first solvent, mix them to obtain a first mixed solution, and dispose the first mixed solution on the light-emitting device preform to form a light-emitting layer 30;

[0097] S13. Perform a heat treatment on the light-emitting device preform provided with the light-emitting layer 30 to cause the first oligopeptide to undergo a cross-linking reaction to form a polypeptide;

[0098] S14. Form a second electrode 50 on the light-emitting layer 30 to obtain the light-emitting device 100;

[0099] Or S11. Provide a light-emitting device preform, where the light-emitting device preform includes a first electrode 10;

[0100] S12. Provide N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mix them to obtain a second mixed solution, and dispose the second mixed solution on the light-emitting device preform and evacuate to form an electron functional layer 40;

[0101] S13. Perform a heat treatment on the light-emitting device preform provided with the electron functional layer 40 to cause the second oligopeptide to undergo a cross-linking reaction to form a polypeptide;

[0102] S14. Form a second electrode 50 on the electron functional layer 40 to obtain the light-emitting device 100.

[0103] In the step S11:

[0104] In some embodiments, the material of the first electrode 10 refers to the above description.

[0105] In some embodiments, the first electrode 10 is a cathode, the second electrode 50 is an anode, and before forming the light-emitting layer 30, forming an electron functional layer 40 on the light-emitting device preform is further included. In some other embodiments, the first electrode 10 is an anode, the second electrode 50 is a cathode, and forming the second electrode 50 on the light-emitting layer 30 includes: forming an electron functional layer 40 and a second electrode 50 on the light-emitting layer 30. In some embodiments, forming the electron functional layer 40 includes: providing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mixing them to obtain a second mixed solution, disposing the second mixed solution on the light-emitting device preform, and evacuating to form an electron functional layer.

[0106] In some embodiments, the first electrode 10 is an anode, the second electrode 50 is a cathode, and before forming the electron functional layer 40, a light-emitting layer 30 is further formed on the light-emitting device preform.

[0107] In some other embodiments, the first electrode 10 is a cathode, the second electrode 50 is an anode, and forming the second electrode 50 on the electron functional layer 40 includes: forming a light-emitting layer 30 and the second electrode 50 on the electron functional layer 40. In some embodiments, forming the electron functional layer 40 includes: providing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mixing them to obtain a second mixed solution, disposing the second mixed solution on the light-emitting device preform or the light-emitting layer 30, and evacuating to form the electron functional layer 40.

[0108] In some embodiments, forming the light-emitting layer 30 includes: providing quantum dots, a first oligopeptide, and a first solvent, mixing them to obtain a first mixed solution, and disposing the first mixed solution on the light-emitting device preform or the electron functional layer 40 to form the light-emitting layer 30.

[0109] In some embodiments, the material of the light-emitting layer 30 is as described above.

[0110] In some embodiments, the electron functional layer 40 includes one or more of an electron injection layer and an electron transport layer.

[0111] In some embodiments, the electron functional material is as described above.

[0112] In some embodiments, the first electrode 10 is an anode, the second electrode 50 is a cathode, and the light-emitting device preform further includes a hole functional layer 20.

[0113] In some other embodiments, the first electrode 10 is a cathode, the second electrode 50 is an anode, and forming the second electrode 50 on the light-emitting layer 30 or the electron functional layer 40 includes forming a hole functional layer 20 and the second electrode 50 on the light-emitting layer 30 or the electron functional layer 40 to obtain the light-emitting device 100.

[0114] In some embodiments, the hole functional layer 20 includes one or more of a hole injection layer and a hole transport layer.

[0115] In some embodiments, the material of the hole functional layer 20 is as described above.

[0116] In step S12:

[0117] In some embodiments, forming the light-emitting layer includes: providing quantum dots, a first oligopeptide, and a first solvent, mixing them to obtain a first mixed solution, and disposing the first mixed solution on the light-emitting device preform to form the light-emitting layer.

[0118] In some embodiments, forming the electron-functional layer includes: providing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mixing them to obtain a second mixed solution, disposing the second mixed solution on the light-emitting device preform, and evacuating to form the electron-functional layer.

[0119] In some embodiments, each of the first oligopeptide and the second oligopeptide independently includes at least one of a dehydration condensate of 2 to 10 amino acids and a derivative of a dehydration condensate of 2 to 10 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine.

[0120] In some embodiments, the first solvent includes one or more of n-octane, dimethylformamide, ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0121] In some embodiments, the mass ratio of the quantum dots to the oligopeptide in the first mixed solution is (5 - 50):1, for example, it can be 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, etc. In this way, the oligopeptide can play a good role in fixing the nanoparticles and at the same time has appropriate charge transport ability.

[0122] In some embodiments, the mass concentration of the first mixed solution is 0.24 - 2.4 mg / ml. Within this range of mass concentration, it is beneficial for the quantum dots and the oligopeptide to be fully dissolved.

[0123] In step S12:

[0124] In some embodiments, the polypeptide includes at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or several of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine.

[0125] In some embodiments, the temperature of the heat treatment reaction is 40 - 120 °C, for example, it can be 45 °C, 50 °C, 55 °C, 60 °C, 65 °C, 70 °C, 75 °C, 80 °C, 85 °C, 90 °C, 95 °C, 100 °C, 105 °C, 110 °C, 115 °C, etc. The time of the heat treatment is 10 - 120 min, for example, it can be 20 min, 30 min, 40 min, 50 min, 60 min, 70 min, 80 min, 90 min, 100 min, 110 min, etc. In this way, the oligopeptides can be fully polymerized into polypeptides, which can better fix the nanoparticles and passivate the surface defects of the nanoparticles, thereby improving the device performance.

[0126] In some embodiments, the first mixed solution obtained by mixing further includes:

[0127] After mixing quantum dots, the first oligopeptide, and the first solvent, irradiate the mixture with ultraviolet light to obtain the first mixed solution.

[0128] In some embodiments, the wavelength of the ultraviolet light is 365 - 430 nm, for example, it can be 370 nm, 380 nm, 385 nm, 390 nm, 395 nm, 400 nm, 405 nm, 410 nm, 415 nm, 420 nm, 425 nm, etc. The time of the ultraviolet light irradiation is 5 - 120 s, for example, it can be 10 s, 20 s, 30 s, 40 s, 50 s, 60 s, 70 s, 80 s, 90 s, 100 s, 110 s, etc. In this way, the groups on the oligopeptide can bind to the defects on the quantum dots, so that while passivating the defects of the quantum dots, the oligopeptide and the quantum dots are bound, further solidifying the nanoparticles.

[0129] In some embodiments, the second solvent includes one or several of n-octane, dimethylformamide, ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol.

[0130] In some embodiments, the mass ratio of the electronic functional material to the second oligopeptide in the second mixed solution is (2 - 50):1. For example, it can be 5:1, 10:1, 15:1, 20:1, 25:1, 30:1, 35:1, 40:1, 45:1, etc. In this way, the oligopeptide can passivate defects well, construct a network structure to fix nanoparticles, and at the same time have appropriate charge transport ability.

[0131] In some embodiments, the mass concentration of the second mixed solution is 0.6 - 15 mg / ml. Within this range of mass concentration, it is beneficial for the full dissolution of the electronic functional material and the oligopeptide.

[0132] In some embodiments, the second mixed solution obtained by mixing further includes:

[0133] Provide an electronic functional material, a second oligopeptide and a second solvent, mix them, and irradiate with ultraviolet light to obtain the second mixed solution.

[0134] In some embodiments, the wavelength of the ultraviolet light is 365 - 430 nm. For example, it can be 370 nm, 380 nm, 385 nm, 390 nm, 395 nm, 400 nm, 405 nm, 410 nm, 415 nm, 420 nm, 425 nm, etc. The irradiation time of the ultraviolet light is 5 - 120 s. For example, it can be 10 s, 20 s, 30 s, 40 s, 50 s, 60 s, 70 s, 80 s, 90 s, 100 s, 110 s, etc. In this way, the free radicals generated by the ultraviolet light can enhance the interaction between substances, and at the same time can induce the occurrence of some cross-linking reactions, thereby promoting the binding of the oligopeptide to the nanoparticles and enhancing the fixing effect.

[0135] In step S14:

[0136] In some embodiments, the material of the second electrode 50 refers to that described above.

[0137] In some embodiments, the formation methods of the first electrode 10, the hole functional layer 20, the light-emitting layer 30, the electron functional layer 40 and the second electrode 50 can be realized by conventional techniques in the art, such as chemical methods or physical methods. Among them, chemical methods include chemical vapor deposition, sequential ionic layer adsorption and reaction, anodic oxidation, electrolytic deposition, coprecipitation. Physical methods include physical coating methods and solution methods. Among them, physical coating methods include: thermal evaporation coating method, electron beam evaporation coating method, magnetron sputtering method, multi-arc ion coating method, physical vapor deposition method, atomic layer deposition method, pulsed laser deposition method, etc.; solution methods can be spin coating method, printing method, inkjet printing method, doctor blade coating method, printing method, dip coating method, immersion method, spraying method, roll coating method, casting method, slot die coating method and bar coating method, etc.

[0138] In a third aspect, an embodiment of the present application further provides a display device, and the display device includes the above-mentioned light-emitting device 100.

[0139] The display device can be any electronic product with a display function. The electronic product includes but is not limited to a smart phone, a tablet computer, a notebook computer, a digital camera, a digital video camera, a smart wearable device, a smart weighing electronic scale, a vehicle-mounted display, a television, or an e-book reader. Among them, the smart wearable device can be, for example, a smart bracelet, a smart watch, a virtual reality (VR) helmet, etc.

[0140] Embodiment 1

[0141] This embodiment further provides a composite material, and the preparation method is as follows:

[0142] Dissolve quantum dots with CdS as the core and CdSe as the shell and acetyl hexapeptide-1 in a mass ratio of 20:1 in n-octane to prepare a first mixed solution with a concentration of 2.4 mg / mL, and obtain the composite material.

[0143] This embodiment further provides a light-emitting device, and the preparation method is as follows:

[0144] Provide ITO glass, dip a cotton swab in a small amount of soapy water and wipe the ITO surface to remove visible impurities on the surface. Then, ultrasonically clean it with deionized water, acetone, ethanol, and isopropanol for 15 min, and then dry it with nitrogen for later use to obtain an ITO anode with a thickness of 110 nm;

[0145] Drop a TFB solution with a concentration of 8 mg / mL on the ITO anode, perform spin coating, control the time at 30 s, and then perform annealing. The annealing temperature is 150 °C, and the annealing time is controlled at 15 min to obtain a hole functional layer with a thickness of 70 nm;

[0146] Set the above-mentioned first mixed solution on the hole functional layer, perform spin coating, the rotation speed of spin coating is 2000 rpm, the time is 30 s, and then perform annealing. The annealing temperature is 80 °C, and the annealing time is 5 min to prepare a light-emitting layer with a thickness of 20 nm;

[0147] Use a pipette to suck 40 μL of a zinc oxide ethanol solution with a concentration of 30 mg / mL, set it on the light-emitting layer, perform spin coating, the rotation speed of spin coating is 4000 rpm, the time is 30 s, and evacuate to form an electron functional layer with a thickness of 40 nm;

[0148] Then perform heat treatment, the temperature of heat treatment is 80 °C, and the time of heat treatment is 30 min;

[0149] On the electron functional layer, turn on the Ag target, and the Ag target is at Evaporate at a rate of 30 nm in thickness to form a cathode;

[0150] Encapsulate to obtain a light-emitting device.

[0151] Example 2

[0152] This example provides a composite material, and the preparation method is as follows:

[0153] Dissolve 30 mg of zinc oxide and 3 mg of acetyl hexapeptide-1 in 1 mL of ethanol solution to obtain a composite material. This example is basically the same as Example 1, except that in this example, acetyl hexapeptide-1 is not added to the light-emitting layer, and the zinc oxide ethanol solution of the electron functional layer material is replaced with the above composite material.

[0154] Example 3

[0155] This example provides a composite material, and the preparation method is as follows:

[0156] Dissolve 30 mg of zinc oxide and 3 mg of acetyl hexapeptide-1 in 1 mL of ethanol solution to obtain a composite material.

[0157] This example is basically the same as Example 1, except that in this example, the zinc oxide ethanol solution of the electron functional layer material is replaced with the above composite material.

[0158] Example 4

[0159] This example is basically the same as Example 3, except that in this example, the mass ratio of quantum dots to acetyl hexapeptide-1 is 5:1.

[0160] Example 5

[0161] This example is basically the same as Example 3, except that in this example, the mass ratio of quantum dots to acetyl hexapeptide-1 is 50:1.

[0162] Example 6

[0163] This example is basically the same as Example 3, except that in this example, the mass ratio of zinc oxide to acetyl hexapeptide-1 is 2:1.

[0164] Example 7

[0165] This example is basically the same as Example 3, except that in this example, the mass ratio of zinc oxide to acetyl hexapeptide-1 is 50:1.

[0166] Example 8

[0167] This example is basically the same as Example 3, except that in this example, the mass concentration of the first mixed solution is 2.4 mg / mL.

[0168] Example 9

[0169] This example is basically the same as Example 3, except that the mass concentration of the first mixed solution in this example is 0.24 mg / mL.

[0170] Example 10

[0171] This example is basically the same as Example 3, except that the mass concentration of the second mixed solution in this example is 15 mg / mL.

[0172] Example 11

[0173] This example is basically the same as Example 3, except that the mass concentration of the second mixed solution in this example is 0.6 mg / mL.

[0174] Example 12

[0175] This example is basically the same as Example 3, except that the temperature of the heat treatment in this example is 120 °C.

[0176] Example 13

[0177] This example is basically the same as Example 3, except that the temperature of the heat treatment in this example is 40 °C.

[0178] Example 14

[0179] This example is basically the same as Example 3, except that the time of the heat treatment in this example is 120 min.

[0180] Example 15

[0181] This example is basically the same as Example 3, except that the time of the heat treatment in this example is 10 min.

[0182] Example 16

[0183] This example is basically the same as Example 3, except that before the first mixed solution is disposed on the hole functional layer in this example, it further includes:

[0184] Irradiating the first mixed solution with a 405 nm ultraviolet lamp for 10 s.

[0185] Example 17

[0186] This example is basically the same as Example 16, except that the wavelength of the ultraviolet lamp in this example is 430 nm.

[0187] Example 18

[0188] This example is basically the same as Example 16, except that in this example, the wavelength of the ultraviolet lamp is 365 nm.

[0189] Example 19

[0190] This example is basically the same as Example 16, except that in this example, the irradiation time of the ultraviolet lamp is 120 s.

[0191] Example 20

[0192] This example is basically the same as Example 16, except that in this example, the irradiation time of the ultraviolet lamp is 5 s.

[0193] Example 22

[0194] This example is basically the same as Example 3, except that in this example, acetyl hexapeptide-1 is replaced with acetyl tetrapeptide-3.

[0195] Example 23

[0196] This example is basically the same as Example 3, except that in this example, acetyl hexapeptide-1 is replaced with palmitoyl tripeptide-1.

[0197] Example 24

[0198] This example is basically the same as Example 1, except that in this example, the quantum dots with CdS as the core and CdSe as the shell are replaced with the quantum dots with CdZnSeS as the core and ZnS as the shell.

[0199] Example 25

[0200] This example is basically the same as Example 1, except that in this example, the quantum dots with CdS as the core and CdSe as the shell are replaced with CdSe quantum dots.

[0201] Example 26

[0202] This example is basically the same as Example 1, except that in this example, an inverted light-emitting device is prepared in the order of cathode, electron functional layer, light-emitting layer, hole functional layer, and anode.

[0203] Comparative Example 1

[0204] This comparative example is basically the same as Example 1, except that in this comparative example, acetyl hexapeptide-1 is not added to the light-emitting layer.

[0205] Comparative Example 2

[0206] This comparative example is basically the same as Example 26, except that in this comparative example, acetyl hexapeptide-1 is not added to the light-emitting layer.

[0207] Comparative Example 3

[0208] This embodiment is basically the same as Embodiment 1, except that a polypeptide layer is provided between the light-emitting layer and the electron-functional layer in this embodiment. The preparation methods of the light-emitting layer, the polypeptide layer, and the electron-functional layer in this embodiment are as follows:

[0209] Dissolve quantum dots with CdS as the core and CdSe as the shell in n-octane to prepare a quantum dot solution with a concentration of 20 mg / mL. Set it on the hole-functional layer and perform spin coating at a rotation speed of 2000 rpm for 30 s. Then perform annealing at an annealing temperature of 100 °C for 5 min to obtain a 20-nm light-emitting layer;

[0210] Mix acetyl hexapeptide-1 and ethanol to obtain an oligopeptide solution with a concentration of 5 mg / ml. Drop the acetyl hexapeptide-1 solution on the light-emitting layer and perform spin coating at a rotation speed of 2000 rpm for 30 s. Then perform annealing at an annealing temperature of 80 °C for 30 min to obtain a 2-nm polypeptide layer;

[0211] Use a pipette to aspirate 40 μL of zinc oxide ethanol solution with a concentration of 30 mg / mL, set it on the polypeptide layer, perform spin coating at a rotation speed of 4000 rpm for 30 s, and evacuate to form an electron-functional layer with a thickness of 40 nm.

[0212] The present application will be specifically described below through specific embodiments. The following embodiments are only partial embodiments of the present application and do not limit the present application. The raw materials used in the following embodiments are all commercially available products unless otherwise specified.

[0213] Perform JVL and T95@1k nit tests on the light-emitting devices of Embodiments 1 to 26 and Comparative Examples 1 to 3, and the test results are shown in Table 1.

[0214] The detection of optoelectronic performance (JVL) is carried out using a FushiDa FSD optical property measurement device (including an efficiency test system built with components such as Ocean Optics USB2000, LabView-controlled QE-PRO spectrometer, Keithley 2400, high-precision digital source meter Keithley 6485, optical fiber with an inner diameter of 50 μm, device test probes and fixtures, various related connection wires and data cards, efficiency test dark box, and data acquisition system) to obtain parameters such as the turn-on voltage, current, brightness, and emission spectrum of each optoelectronic device, and then calculate key parameters such as external quantum efficiency and power efficiency.

[0215] The detection method of current efficiency and voltage includes the steps: Set the light-emitting area to 2 mm × 2 mm = 4 mm 2, intermittently collect the brightness values of the optoelectronic device within the voltage range of 0V to 8V. The initial voltage value for collecting brightness is 3V, and it is collected every 0.2V. The brightness value collected each time is divided by the corresponding current density to obtain the current efficiency of the optoelectronic device under the collection conditions of this time, and the current density of 32 mA / cm 2 is obtained for the current efficiency (C.E1, cd / A) and voltage value (U1, V).

[0216] The detection method for device efficiency and voltage stability includes the steps: After placing the encapsulated optoelectronic device in an environment with a temperature of 80°C and a relative humidity of 80% for 7 days, intermittently collect the brightness values of the optoelectronic device within the voltage range of 0V to 8V, collect it every 0.2V, and the brightness value collected each time is divided by the corresponding current density to obtain the current efficiency of the optoelectronic device under the collection conditions of this time, and the current density of 32 mA / cm 2 is obtained for the current efficiency (C.E2, cd / A) and voltage value (U2, V), and calculate to obtain CE d (%) = C.E2 / C.E1 × 100%. The larger the A%, the higher the stability of the device efficiency of the optoelectronic device; conversely, the smaller the A%, the lower the stability of the device efficiency of the optoelectronic device; calculate to obtain U d (%) = U2 / U1 × 100%. The larger the C%, the higher the stability of the device voltage of the optoelectronic device; conversely, the smaller the C%, the lower the stability of the device voltage of the optoelectronic device.

[0217] T95@1k nit is tested using a 128-channel lifetime test system customized by Guangzhou New Vision Company. The system architecture is a constant voltage and constant current source driving QLED. Test the changes in the test voltage or current, and the photodiode detector and the test system test the changes in the brightness (photoelectric current) of QLED. The brightness meter tests and calibrates the brightness (photoelectric current) of QLED to obtain the time experienced for the initial brightness of the light-emitting diode to decay to 95%, and the driving current is 2 mA; T95@1k nit refers to the time experienced for the initial brightness of the device to decay to 95%, and it is converted to the aging time under 1k nit.

[0218] Table 1

[0219]

[0220]

[0221] As can be seen from Table 1:

[0222] Compared with Comparative Examples 1-3, the lifetime, current efficiency, and stability of the light-emitting devices of Examples 1, 2, and 26 were improved. This is due to the addition of oligopeptides to the light-emitting layer and the addition of oligopeptides to the electron functional layer, which passivated and fixed the defects on the surface of the nanoparticles in the light-emitting layer and the electron functional layer. Compared with Example 3, the current efficiency and lifetime of the light-emitting device of Example 16 were improved. This is due to the prior ultraviolet light irradiation of the oligopeptides in the electron functional layer and the light-emitting layer, which enhanced the interaction between substances by the free radicals generated by the ultraviolet light, induced the occurrence of partial crosslinking reactions, promoted the binding of oligopeptides to nanoparticles, and enhanced the fixing effect.

[0223] The light-emitting devices provided in the embodiments of the present application have been introduced in detail above. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A composite material, characterized in that: It includes nanoparticles and polypeptides.

2. The composite material according to claim 1, characterized in that: The nanoparticles include one or more of N-type inorganic semiconductor particles and quantum dots; and / or The polypeptide includes at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine.

3. The composite material according to claim 2, wherein: The mass ratio of the quantum dots to the polypeptide is (5 - 50):1; and / or The mass ratio of the N-type inorganic semiconductor particles to the polypeptide is (2 - 50):1; and / or The average particle size of the quantum dots is 5 - 15 nm; and / or The average particle size of the N-type inorganic semiconductor particles is 2 - 10 nm; and / or The N-type inorganic semiconductor particles include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5; the metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, Al2O3, and the dopants in the doped metal oxides include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, Sn; the IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, CdS; the IIIA-VA group semiconductor materials include one or more of InP, GaP; the IB-IIIA-VIA group semiconductor materials include one or more of CuInS, CuGaS; and / or The quantum dots include one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite quantum dots; the materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots include one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the shell of the core-shell structure quantum dots is one or more layers; the II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; the IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group 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; the I-III-VI group compounds include one or more of CuInS2, CuInSe2, and AgInS2;The quantum dots with core-shell structure include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS; the perovskite quantum dots include doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the structural general formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; the structural general formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation, including CH3(CH2) n-2 NH 3+ or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them.

4. A light-emitting device, characterized in that: It includes a first electrode, a functional layer, and a second electrode arranged in a stacked manner, wherein The functional layer includes a light-emitting layer, and the material of the light-emitting layer includes quantum dots and a first polypeptide; and / or The functional layer includes an electron functional layer, and the material of the electron functional layer includes N-type inorganic semiconductor particles and a second polypeptide.

5. The light-emitting device according to claim 4, wherein: The mass ratio of the quantum dots to the first polypeptide is (5 - 50):1; and / or The mass ratio of the N-type inorganic semiconductor particles to the second polypeptide is (2 - 50):1; and / or The thickness of the light-emitting layer is 10 - 30 nm; and / or The thickness of the electron functional layer is 20 - 60 nm; and / or The average particle size of the quantum dots is 5 - 15 nm; and / or The average particle size of the N-type inorganic semiconductor particles is 2 - 10 nm.

6. The light-emitting device according to claim 4, characterized in that: The first polypeptide and the second polypeptide each independently include at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or The quantum dots include one or more of single-structure quantum dots, core-shell structure quantum dots, and perovskite quantum dots; the materials of the single-structure quantum dots, the core materials of the core-shell structure quantum dots, and the shell materials of the core-shell structure quantum dots include one or more of II-VI group compounds, IV-VI group compounds, III-V group compounds, and I-III-VI group compounds; the shell of the core-shell structure quantum dots is one or more layers; the II-VI group compounds include one or more of CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, and HgZnSTe; the IV-VI group compounds include one or more of SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, and SnPbSTe; the III-V group 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; the I-III-VI group compounds include one or more of CuInS2, CuInSe2, and AgInS2;The quantum dots with core-shell structure include one or more of CdSe / CdSeS / CdS, InP / ZnSeS / ZnS, CdZnSe / ZnSe / ZnS, CdSeS / ZnSeS / ZnS, CdSe / ZnS, CdSe / ZnSe / ZnS, ZnSe / ZnS, ZnSeTe / ZnS, CdSe / CdZnSeS / ZnS and InP / ZnSe / ZnS; the perovskite quantum dots include doped or undoped inorganic perovskite semiconductors, or organic-inorganic hybrid perovskite semiconductors; the structural general formula of the inorganic perovskite semiconductor is AMX3, where A is Cs + ion, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; the structural general formula of the organic-inorganic hybrid perovskite semiconductor is BMX3, where B is an organic amine cation, including CH3(CH2) n-2 NH 3+ or [NH3(CH2) n NH3] 2+ , where n≥2, M is a divalent metal cation, including Pb 2+ 、Sn 2+ 、Cu 2+ 、Ni 2+ 、Cd 2+ 、Cr 2+ 、Mn 2+ 、Co 2+ 、Fe 2+ 、Ge 2+ 、Yb 2+ 、Eu 2+ one or more of them, and X is a halogen anion, including Cl - 、Br - 、I - one or more of them; and / or The electronic functional layer includes one or more of an electron injection layer and an electron transport layer. The material of the electronic functional layer includes one or more of inorganic electronic functional materials and organic electronic functional materials. The N-type inorganic semiconductor particles include one or more of metal oxides, doped metal oxides, IIB-VIA group semiconductor materials, IIIA-VA group semiconductor materials, and IB-IIIA-VIA group semiconductor materials. The metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, and Ta2O5. The metal oxides in the doped metal oxides include one or more of ZnO, TiO2, SnO2, ZrO2, Ta2O5, and Al2O3. The dopants in the doped metal oxides include one or more of Al, Mg, Li, Mn, Y, La, Cu, Ni, Zr, Ce, In, Ga, and Sn. The IIB-VIA group semiconductor materials include one or more of ZnS, ZnSe, and CdS. The IIIA-VA group semiconductor materials include one or more of InP and GaP. The IB-IIIA-VIA group semiconductor materials include one or more of CuInS and CuGaS. The organic electronic functional materials include one or more of quinoxaline compounds, imidazole compounds, triazine compounds, fluorene-containing compounds, and hydroxyquinoline compounds; and / or The materials of the first electrode and the second electrode each independently include one or more of metals, carbon materials, and metal oxides. The metals include one or more of Al, Ag, Cu, Mo, Au, Ba, Ca, Yb, and Mg. The carbon materials include one or more of graphite, carbon nanotubes, graphene, and carbon fibers. The metal oxides include metal oxide electrodes or composite electrodes with a metal sandwiched between doped or undoped transparent metal oxides. The materials of the metal oxide electrodes include one or more of ITO, FTO, ATO, AZO, GZO, IZO, MZO, MoO3, and AMO. The composite electrodes include one or more of AZO / Ag / AZO, AZO / Al / AZO, ITO / Ag / ITO, ITO / Al / ITO, ZnO / Ag / ZnO, ZnO / Al / ZnO, ZnS / Ag / ZnS, ZnS / Al / ZnS, TiO2 / Ag / TiO2, and TiO2 / Al / TiO2; and / or The light-emitting device further includes a hole functional layer disposed between the light-emitting layer and the first electrode or the second electrode. The hole functional layer includes one or more of a hole injection layer and a hole transport layer. The material of the hole functional layer includes 4,4'-N,N'-dicarbazolyl-biphenyl, N,N'-diphenyl-N,N'-bis(1-naphthyl)-1,1'-biphenyl-4,4”-diamine, N,N'-diphenyl-N,N'-bis(3-methylphenyl)-(1,1'-biphenyl)-4,4'-diamine, N,N'-bis(3-methylphenyl)-N,N'-bis(phenyl)-spiro, N,N'-bis(4-(N,N'-diphenyl-amino)phenyl)-N,N'-diphenylbenzidine, 4,4',4'-tris(N-carbazolyl)-triphenylamine, 4,4',4'-tris(carbazol-9-yl)triphenylamine, trichloroisocyanuric acid, terbium-doped phosphate-based green light-emitting material, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene, 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine, poly[(9,9'-dioctylfluorene-2,7-diyl)-co-(4,4'-(N-(4-sec-butylphenyl)diphenylamine))], poly(4-butylphenyl-diphenylamine), poly[bis(4-phenyl)(4-butylphenyl)amine], polyaniline, polypyrrole, poly(p-phenylene vinylene), poly(phenylene vinylene), poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylene vinylene], poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylene vinylene], copper phthalocyanine, aromatic tertiary amine, polynuclear aromatic tertiary amine, 4,4'-bis(p-carbazolyl)-1,1'-biphenyl compound, N,N,N',N'-tetraarylbenzidine, PEDOT, PEDOT:PSS and its derivatives, PEDOT:PSS derivatives doped with s-MoO3, poly(N-vinylcarbazole) and its derivatives, polymethacrylate and its derivatives, poly(9,9-octylfluorene) and its derivatives, poly(spirofluorene) and its derivatives, N,N'-bis(naphthalen-1-yl)-N,One or more of N'-diphenylbenzidine, spiro-NPB, nanocrystalline diamond, microcrystalline cellulose, tetracyanoquinodimethane, doped graphene, undoped graphene, second doped metal oxide particles, second undoped metal oxide particles, metal sulfides, metal selenides, and metal nitrides, wherein the metal oxides in the second doped metal oxide particles and the metal oxides in the second undoped metal oxide particles independently include one or more of MoO3, WO3, NiO, CrO3, CuO, and V2O5, the doping elements in the second doped metal oxide particles include one or more of Mo, W, Ni, Cr, Cu, and V, the metal sulfides include one or more of CuS, MoS3, and WS3, the metal selenides include one or more of MoSe3 and WSe3, and the metal nitrides include p-type gallium nitride., 7. A method for preparing a light-emitting device, characterized in that, It includes the following steps: Provide a light-emitting device preform, and the light-emitting device preform includes a first electrode; Provide a light-emitting material and / or an electron-functional material, and dispose the light-emitting material and / or the electron-functional material on the light-emitting device preform to form a light-emitting layer and / or an electron-functional layer. The light-emitting material includes quantum dots and a first oligopeptide, and the electron-functional material includes N-type inorganic semiconductor particles and a second oligopeptide; Perform a heat treatment on the light-emitting device preform provided with the light-emitting layer and / or the electron-functional layer to cause a cross-linking reaction of the first oligopeptide and / or the second oligopeptide to form a polypeptide; Form a second electrode on the light-emitting layer or the electron-functional layer to obtain a light-emitting device.

8. The preparation method according to claim 7, characterized in that, The forming of the light-emitting layer includes: providing quantum dots, a first oligopeptide, and a first solvent, mixing to obtain a first mixed solution, and disposing the first mixed solution on the light-emitting device preform to form a light-emitting layer; and / or The forming of the electron-functional layer includes: providing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, mixing to obtain a second mixed solution, disposing the second mixed solution on the light-emitting device preform, and evacuating to form an electron-functional layer.

9. The preparation method according to claim 8, characterized in that, The mixing to obtain the second mixed solution further includes: After mixing N-type inorganic semiconductor particles, a second oligopeptide, and a second solvent, irradiating with ultraviolet light to obtain a second mixed solution; and / or The mixing to obtain the first mixed solution further includes: After mixing quantum dots, a first oligopeptide, and a first solvent, irradiating with ultraviolet light to obtain a first mixed solution.

10. The preparation method according to claim 9, characterized in that, The first oligopeptide and the second oligopeptide each independently include at least one of a dehydration condensate of 2-10 amino acids and a derivative of a dehydration condensate of 2-10 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or The polypeptide includes at least one of a dehydration condensate of at least 11 amino acids and a derivative of a dehydration condensate of at least 11 amino acids; the amino acids include one or more of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, histidine, selenocysteine, and pyrrolysine; and / or The mass ratio of the quantum dots to the first oligopeptide is (5-50):1; and / or The mass ratio of the N-type inorganic semiconductor particles to the second oligopeptide is (2-50):1; and / or The thickness of the light-emitting layer is 10-30 nm; and / or The thickness of the electron-functional layer is 20-60 nm; and / or The average particle size of the quantum dots is 5-15 nm; and / or The mass concentration of the first mixed solution is 0.24-2.4 mg / ml; and / or The first solvent and the second solvent each independently include one or more of n-octane, dimethylformamide, ethanol, diethylene glycol monobutyl ether, trimethoxybutanol, triethylene glycol monobutyl ether, diethylene glycol dimethyl ether, ethanol, methanol, ethanol, propanol, butanol, ethylene glycol, isopropanol, glycerol, dimethyl sulfoxide, acetone, acetophenone, tetrahydrofuran, N,N-dimethylformamide, ethyl acetate, pyrrole, butyric acid, and cresol; and / or The mass concentration of the second mixed solution is 0.6 - 15 mg / ml; and / or The temperature of the heat treatment is 40 - 120 °C, and the time of the heat treatment is 10 - 120 min; and / or The wavelength of the ultraviolet light is 365 - 430 nm, and the time of the ultraviolet light irradiation is 5 - 120 s.

11. The preparation method according to claim 8, characterized in that, The first electrode is the anode, the second electrode is the cathode, and the light-emitting device preform includes the first electrode and the hole functional layer; or The first electrode is the cathode, the second electrode is the anode, and forming the second electrode on the light-emitting layer or the electron functional layer includes forming the hole functional layer and the second electrode on the light-emitting layer or the electron functional layer to obtain the light-emitting device.

12. A display device, characterized in that: The display device includes the light-emitting device according to any one of claims 4 to 6, or the light-emitting device prepared by the preparation method according to any one of claims 7 to 11.

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