Quantum dots and ink compositions, optical members and electronic devices comprising quantum dots

Abstract

The present invention provides a quantum dot, and an ink composition, an electronic device, and an optical member containing the quantum dot, the quantum dot including: a core including a crystal of a first semiconductor; a shell located on the core and including a crystal of at least one second semiconductor; a first region located on the shell and including a first ligand; and an outer layer located on the first region and including an oligomer or polymer containing a metal and a polar organic group.

Description

[0001] Cross-reference to related applications

[0002] This application is based on and claims priority to Korean Patent Application No. 10-2021-0008260, filed with the Korean Intellectual Property Office on January 20, 2021, and Korean Patent Application No. 10-2021-0107537, filed on August 13, 2021, the disclosures of which are incorporated herein by reference in their entirety. background 1. Technical Field

[0004] One or more embodiments relate to quantum dots and ink compositions, optical components, and electronic devices containing the quantum dots.

[0005] 2. Description of related technologies

[0006] Quantum dots, nanocrystals that are semiconductor materials, exhibit quantum confinement effects. When quantum dots receive light from an excitation source and reach an excited state, they emit energy corresponding to their own band gap. In this case, because the wavelength of the same material can vary depending on the particle size, light with a desired wavelength can be obtained by adjusting the size of the quantum dots. Furthermore, due to properties such as excellent color purity and high luminous efficiency, quantum dots can be applied to a wide variety of devices.

[0007] Furthermore, in optical components, quantum dots can be used as materials to perform various optical functions, such as light conversion. Quantum dots are semiconductor nanocrystals with a size of a few nanometers. By adjusting the size and composition of the nanocrystals, different energy band gaps can be achieved, thereby emitting light of various wavelengths.

[0008] Optical components incorporating such quantum dots can have thin-film shapes, such as thin-film shapes patterned for each subpixel. Such optical components can be used as color conversion components in devices that incorporate various light sources. Summary of the Invention

[0009] One or more embodiments include quantum dots and ink compositions, optical components, and electronic devices containing the quantum dots, wherein the quantum dots exhibit excellent dispersibility and improved efficiency in polar solvents, and nonpolar ligands do not detach from the quantum dots coordinated to the surface of the nonpolar ligands.

[0010] Other aspects will be set forth in part in the description which follows, and other aspects will follow the description, and will be apparent in part from the description, or may be learned by practicing the embodiments set forth in this invention.

[0011] According to one or more embodiments, a quantum dot includes: a core comprising a crystal of a first semiconductor; a shell comprising a crystal of at least one second semiconductor located on the core; a first region comprising a first ligand located on the shell; and an outer layer comprising an oligomer or polymer containing a metal and a polar organic group located on the first region.

[0012] According to one or more embodiments, the ink composition comprises quantum dots.

[0013] According to one or more embodiments, the optical component comprises quantum dots.

[0014] According to one or more embodiments, the electronic device includes a first electrode, a second electrode facing the first electrode, an intermediate layer inserted between the first electrode and the second electrode, and an external color conversion member configured to face one or more of the first electrode and the second electrode of the intermediate layer, wherein the color conversion member comprises quantum dots. Attached Figure Description

[0015] The above and other aspects, features, and advantages of certain embodiments of the present invention will become more apparent from the following description taken in conjunction with the accompanying drawings, wherein

[0016] Figure 1 This is a schematic diagram of a quantum dot according to an embodiment of the present invention;

[0017] Figure 2 A schematic diagram illustrating the structure of a light-emitting device according to an embodiment of the present invention;

[0018] Figure 3 A schematic diagram illustrating the structure of a light-emitting device according to an embodiment of the present invention; Figure 4 A graph showing the photoluminescence quantum efficiency of Control 1 and Control 2 as measured using the QE-2100 device; and Figure 5 Images showing the dispersion of Control 1 and Control 2 after 24 hours. Detailed Implementation

[0019] Reference will now be made in detail to embodiments, examples of which are shown in the accompanying drawings, wherein the same reference numerals always denote the same elements. In this respect, embodiments of the invention may take different forms and should not be construed as limited to the description set forth herein. Therefore, embodiments are described below only with reference to the accompanying drawings to explain various aspects of this description. As used herein, the term “and / or” includes any and all combinations of more than one of the related listed items. Throughout the disclosure, the expression “at least one of a, b, and c” means only a, only b, only c, both a and b, both a and c, both b and c, all a, b, and c, or variations thereof.

[0020] Because the invention allows for various variations and numerous embodiments hereinafter, specific embodiments will be shown in the accompanying drawings and described in detail in the written description. The effects and features of the invention, as well as methods for achieving these effects and features, will become apparent from the embodiments described below in conjunction with the accompanying drawings. However, the invention is not limited to these embodiments, but can be implemented in many different forms.

[0021] In the following, embodiments according to the invention will be described in detail with reference to the accompanying drawings. In the drawings, the same reference numerals denote the same elements or components having substantially the same function, and repeated descriptions will be omitted.

[0022] In the following implementation, the terms "first," "second," etc., are used to distinguish one component from other components; therefore, the component is not limited by these terms.

[0023] The singular form encompasses the plural form unless it has a distinctly different meaning in the context.

[0024] In the following implementation, it should be understood that the terms “comprising” or “having” are intended to indicate the presence of the elements disclosed in the specification and are not intended to exclude the possibility that one or more other elements may be present or may be added.

[0025] In the following embodiments, it should be understood that when an element (e.g., a layer, film, region, or plate) is referred to as being "above" another element, it can be located directly above the other element, or there may be an intermediate element between them. Furthermore, for ease of interpretation, the dimensions of elements in the figures may be enlarged or reduced. For example, since the dimensions and thicknesses of components in the figures are arbitrarily shown for ease of interpretation, the following embodiments are not limited thereto.

[0026]

Quantum dot

[0027] Figure 1 This is a schematic diagram illustrating the structure of a quantum dot according to an embodiment of the present invention.

[0028] refer to Figure 1 The quantum dot 1 includes: a core 11 containing a crystal of a first semiconductor; a shell 12 located on the core and containing a crystal of at least one second semiconductor; a first region 13 located on the shell and containing a first ligand; and an outer layer 14 located on the first region 13 and containing a polymer or oligomer containing a metal and a polar organic group.

[0029] Because quantum dots have a core / shell structure containing semiconductor crystals, a first region containing nonpolar ligands is located on the surface of the shell, and an outer layer is located on the first region to surround the first region and the outer layer contains a polymer of monomers represented by Formula 1 below, which can prevent the loss of semiconductor metal and the shedding of the first ligands, thereby suppressing the degradation of quantum dots.

[0030] Furthermore, because quantum dots include an outer layer containing a polymer with metal and polar organic groups, the metal lost from the shell surface is partially compensated to improve quantum efficiency, and the dispersibility and compatibility of quantum dots in polar solvents are also improved by the polymer containing polar organic groups to improve processability.

[0031] According to the implementation scheme, the metal may include Cd, Zn, Hg, Mg, Ga, Al, In, Sn, Pb, Si, Ge, Ag, Cu or any combination thereof, but is not limited thereto.

[0032] For example, the metal could be Zn, In, Cd, or Ga.

[0033] According to the implementation scheme, the metal may contain the same metal as the metal contained in the crystal of the second semiconductor.

[0034] For example, if the crystal of the second semiconductor contains a combination of two or more metals, the oligomer or polymer may contain at least one of the two or more metals.

[0035] According to the implementation scheme, the polar organic group may include, but is not limited to, hydroxyl, carbonyl, acryloyl, ester, ether, carboxyl, epoxy, halogen group or any combination thereof, and any functional group capable of providing polarity to the molecule may also be used.

[0036] For example, the polar organic group can be acryloyl, epoxy, ether or carboxyl.

[0037] According to the implementation scheme, the polymer or oligomer may comprise a polymeric product of a monomer represented by Formula 1 below:

[0038] <Formula 1>

[0039]

[0040] In Equation 1,

[0041] M includes Cd, Zn, Hg, Mg, Ga, Al, In, Sn, Pb, Si, Ge, Ag, Cu, or any combination thereof.

[0042] Y is an ionic group.

[0043] A1 and A2 are each independently selected from unsubstituted or R-substituted products.10a Replacement C1-C 20 Alkylene and unsubstituted or with at least one R 10a Replacement C2-C 20 Sub-alkenyl,

[0044] a1 and a2 are each independent integers selected from 0 to 10.

[0045] When a1 is an integer of 2 or greater, two or more A1s are the same or different; and when a2 is an integer of 2 or greater, two or more A2s are the same or different.

[0046] P1 and P2 are each independently selected from *-O-*', *-S-*', *-C(=O)-*', *-S(=O)2-*', *-C(=O)(O)-*', *-C(R1)=C(R2)-C(=O)OR3-*', *-OC(=O)-C(R1)=C(R2)-*', and *-C(R1)(R2)-*'.

[0047] b1 and b2 are each independent integers selected from 1 to 10.

[0048] When b1 is an integer of 2 or greater, two or more P1s are the same or different; and when b2 is an integer of 2 or greater, two or more P2s are the same or different.

[0049] c1 and c2 are integers selected from 0 to 10.

[0050] When c1 is an integer of 2 or greater, two or more *–(A1) a1 -(P1) b1 –*'Same or different, and when c2 is an integer of 2 or greater, 2 or more *–(A2) a2 -(P2) b2 –*'Same or different'

[0051] R1 to R3 are each independently selected from hydrogen, hydroxyl, alkoxy, epoxy, and halogen groups.

[0052] R 10a Selected from hydrogen, C1-C 20 Alkyl and C2-C 20 Alkenyl,

[0053] n is an integer selected from 1 to 5.

[0054] When n is an integer of 2 or greater, 2 or more Same or different, and

[0055] Z is a crosslinkable group, which includes at least one of an olefinic unsaturated group, an epoxy group, an alkoxy group, and an isocyanate group.

[0056] According to the implementation scheme, the ionic group can be an anionic group. For example, the ionic group can be a mercapto, carboxyl, amino, phosphate, sulfate, or nitrate group. As used herein, the term "ionic group" refers to a functional group that exists in aqueous solution in ionic form and is capable of forming a salt with a metal.

[0057] According to the implementation plan, the ionic group can be a carboxyl group.

[0058] According to the implementation scheme, the polymer may further include ionic groups, and the ionic groups may be attached to the metal in the form of a metal salt.

[0059] According to the implementation plan, the outer layer may further include the aforementioned monomers.

[0060] According to the implementation scheme, M in Formula 1 may include the same metal as the metal contained in the crystal of the second semiconductor. Therefore, some monomers that do not constitute the polymer are dispersed in the first region to correct defects on the shell surface, thus improving the quantum efficiency of the quantum dot.

[0061] According to the implementation scheme, the polymer may include a crosslinked polymer generated by crosslinking crosslinkable groups through light (e.g., UV light), heat, or crosslinking groups.

[0062] For example, the cross-linked polymer can be a network cross-linked polymer.

[0063] According to the implementation scheme, when a1 is 0, A1 is a single bond, and the group adjacent to Y can directly bond with it. When a2 is 0, A2 is a single bond, and the group adjacent to P1 can directly bond with it.

[0064] According to the implementation plan, A1 and A2 can each be independently C1-C. 10 Alkylene. For example, A1 and A2 can be ethylene, respectively.

[0065] According to the implementation plan, P1 and P2 can each be independently *-O-*', *-S-*', *-C(=O)-*', or *-C(=O)(O)-*'. For example, P1 and P2 may each be *-O-*'.

[0066] According to the implementation scheme, Z can be a group selected from the following formulas 1-1 to 1-6:

[0067]

[0068] In equations 1-1 to 1-6,

[0069] R11 To R 15 Each can be independently selected from hydrogen, -F, -Cl, -Br, -I, Cl-C 20 Alkyl and C2-C 20 Alkenyl group.

[0070] For example, R 11 To R 15 Each can be selected independently from:

[0071] Hydrogen, -F, -Cl, -Br, -I, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, tert-pentyl, neopentyl, isopentyl, sec-pentyl, 3-pentyl, sec-isopentyl, n-hexyl, isohexyl, sec-hexyl, tert-hexyl, n-heptyl, isoheptyl, sec-heptyl, tert-heptyl, n-octyl, isooctyl, sec-octyl, tert-octyl, n-nonyl, isonyl, sec-nonyl, tert-nonyl, n-decyl, isodecyl, sec-decyl, and tert-decyl, but not limited thereto.

[0072] For example, R 11 To R 13 Each of them can be independently selected from hydrogen, methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, tert-pentyl, neopentyl, isopentyl, sec-pentyl, 3-pentyl, sec-isopentyl, n-hexyl, isohexyl, sec-hexyl, and tert-hexyl.

[0073] According to the implementation plan, the first ligand may contain C1-C 20 Hydrocarbon group.

[0074] For example, the first ligand may comprise a C1-C having at least one olefinically unsaturated group. 20 Hydrocarbon group.

[0075] According to the implementation scheme, the first ligand may further include an ionic group. For example, the ionic group may be a thiol group, carboxyl group, amino group, phosphate group, sulfate group, or nitrate group.

[0076] According to the implementation plan, the first ligand may contain ionic groups and C1-C2 groups. 20 Hydrocarbon groups. For example, ionic groups are bonded to the shell surface via coordination covalent bonds, and C1-C 20 The hydrocarbon group can be oriented towards the outer layer. For example, the first ligand can be oleic acid.

[0077] According to the implementation scheme, the first semiconductor and the second semiconductor may each independently comprise: a group II-VI semiconductor compound; a group III-V semiconductor compound; a group III-VI semiconductor compound; a group I-III-VI semiconductor compound; a group IV-VI semiconductor compound; a group IV element or compound; or any combination thereof.

[0078] Examples of group II-VI semiconductor compounds may include: binary compounds such as CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, and MgS; ternary compounds such as CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, and CdZnS. nSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe and MgZnS; quaternary compounds, such as CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe and HgZnSTe; or any combination thereof.

[0079] Examples of group III-V semiconductor compounds may include: binary compounds, such as GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, and InSb; ternary compounds, such as GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs, and InPSb; and quaternary compounds, such as GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, and InAlPSb; or any combination thereof. Furthermore, group III-V semiconductor compounds may further contain group II elements. Examples of further group III-V semiconductor compounds containing group II elements may include InZnP, InGaZnP, and InAlZnP.

[0080] Examples of group III-VI semiconductor compounds may include: binary compounds, such as GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2Se3, and InTe; ternary compounds, such as InGaS3 and InGaSe3; or any combination thereof.

[0081] Examples of group I-III-VI semiconductor compounds may include: ternary compounds, such as AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2, and AgAlO2; or any combination thereof.

[0082] Examples of group IV-VI semiconductor compounds may include: binary compounds, such as SnS, SnSe, SnTe, PbS, PbSe, and PbTe; ternary compounds, such as SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, and SnPbTe; quaternary compounds, such as SnPbSSe, SnPbSeTe, and SnPbSTe; or any combination thereof.

[0083] IV elements or compounds may include: single elements, such as Si and Ge; binary compounds, such as SiC and SiGe; or any combination thereof.

[0084] Each element contained in a multi-element compound (such as a binary, ternary, or quaternary compound) can exist in the quantum dot particles in a uniform or non-uniform concentration.

[0085] Furthermore, quantum dots can have a single structure or a core-shell dual structure, wherein each element contained in the quantum dot has a uniform concentration. For example, the material contained in the core can be different from the material contained in the shell.

[0086] The shell of a quantum dot can serve as a protective layer to maintain semiconductor properties by inhibiting chemical modification of the core; and / or as a charging layer to provide electrophoretic properties to the quantum dot. The shell can have a single-layer or multi-layer structure. The interface between the core and shell can have a concentration gradient, where the concentration of elements present in the shell decreases towards the center.

[0087] According to the implementation scheme, the first semiconductor may include GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InAlP, InNP, InNAs, InNSb, InPAs, InPSb, InZnP, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, or other semiconductors. Any combination thereof, and the second semiconductor may include: CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgS, MgSe, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnS, MgZnSe, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe, HgZnSTe, or any combination thereof, and is not limited thereto.

[0088] According to the implementation plan, the shell can have a single-layer or multi-layer structure.

[0089] According to the implementation scheme, the shell can be a composite monolayer shell containing crystals of two different types of second semiconductors. In this case, the aforementioned first region containing the first ligand can be disposed on at least a portion of the composite monolayer shell, or cover the entire outer surface of the composite monolayer shell.

[0090] According to the implementation plan, the shell may contain two different types of semiconductor particles containing Zn metal.

[0091] According to the implementation scheme, the shell may contain two different types of group II-IV semiconductor compounds. For example, the shell may include ZnSe and ZnS.

[0092] According to the implementation scheme, the shell may comprise a double-layered shell containing a first shell and a second shell, and the first shell may be inserted between the core and the second shell. In this case, the first shell and the second shell may comprise crystals of different second semiconductors.

[0093] For example, the first shell may include ZnSe, and the second shell may include ZnS.

[0094] Quantum dots emit visible light. For example, quantum dots can emit light with various maximum emission wavelengths depending on their diameter. As an example, quantum dots can emit light with maximum emission wavelengths ranging from 430 nm to 800 nm. Therefore, when quantum dots are applied to color conversion components, high brightness and high color purity can be achieved.

[0095] According to the implementation scheme, quantum dots can have an average diameter of 1 nm to 15 nm. For example, quantum dots can have an average diameter of 2 nm to 13 nm or 2 nm to 10 nm.

[0096] According to the implementation scheme, there are no particular limitations on the shape of the quantum dots, and quantum dots can have any shape commonly used in the art. For example, quantum dots can be in the form of nanoparticles, nanotubes, nanowires, nanofibers, or nanoplates with spherical, pyramidal, multi-armed, or cubic shapes.

[0097] Ink Composition

[0098] According to another embodiment, an ink composition comprising the aforementioned quantum dots is provided.

[0099] According to the embodiments, the ink composition can be a solvent-free ink composition that is substantially free of solvents. For example, the ink composition may contain solvents that inevitably remain after the preparation of quantum dots, and the amount of solvent may be about 5 wt% or less based on the total weight of the composition. The solvents remaining in the quantum dots can be removed by an additional purification process.

[0100] Because the ink composition does not contain solvent, a simplified process and economic feasibility can be achieved by omitting the solvent removal stage.

[0101] According to the embodiments, in the ink composition, the amount of quantum dots can be from 0.1 wt% to 50 wt%, specifically, from 10 wt% to 50 wt%, or from 10 wt% to 45 wt%, based on the total weight of the composition.

[0102] The viscosity of the ink composition at room temperature (e.g., 25°C) can be from 1 cP to 30 cP. For example, the viscosity of the ink composition can be from 5 cP to 30 cP, 10 cP to 30 cP, or 20 cP to 25 cP. Ink compositions with viscosities within the above ranges are suitable for preparing color conversion components located outside of light-emitting devices or for preparing quantum dot light-emitting layers.

[0103] According to the embodiments, the ink composition may further comprise a polymerization initiator. The polymerization initiator may include a thermal polymerization initiator and / or a photopolymerization initiator.

[0104] As thermal polymerization initiators, any compound capable of forming free radicals by heating can be used without limitation. Examples of thermal polymerization initiators may include: persulfate-based compounds, such as sodium persulfate (Na2S2O8), potassium persulfate (K2S2O8), and ammonium persulfate ((NH4)2S2O8); azo compounds, such as 2,2-azobis(2-amidinylpropane) dihydrochloride, 2,2-azobis-(N,N-dimethylene)isobutyramidine dihydrochloride, 2-(carbamoylazo)isobutyronitrile, 2,2-azobis[2-(2-imidazolin-2-yl)propane] dihydrochloride, 4,4-azobis(4-cyanopentanoic acid); hydrogen peroxide, or any combination thereof.

[0105] When using a thermal polymerization initiator, the amount can be from 0.01 parts by weight to 15 parts by weight, based on the total weight of the ink composition.

[0106] As a photopolymerization initiator, any compound capable of forming free radicals by UV light with a maximum emission wavelength of 200 nm to 400 nm can be used without limitation, and examples of photopolymerization initiators may include cations selected from arylsulfonium, aryldiazoonium, or arylammonium and cations selected from AsF6. - SbF6 - PF6 - Compounds consisting of combinations of anions in tetra(pentafluorophenyl)borate, or organosilanes.

[0107] When using a photopolymerization initiator, the amount can be from 0.01 parts by weight to 15 parts by weight, based on the total weight of the ink composition.

[0108] According to the implementation scheme, the ink composition may further include various additives to improve the spraying and applicability of the ink composition, thereby improving the optical properties of the film cured therefrom without affecting the physical properties of the quantum dots.

[0109] For example, the ink composition may further include dispersants, viscosity modifiers, etc., known in the art, to improve spraying performance and applicability, and may further include surfactants, scatterers, defoamers, UV stabilizers, hygroscopic agents, antioxidants, etc., known in the art, to improve the optical properties of the cured film. In this case, the additives can be used in amounts that do not affect the physical properties of the quantum dots.

[0110] According to the embodiments, the ink composition may further comprise diacrylate-based monomers. For example, the diacrylate-based monomers may include alkyl glycol diacrylate monomers. For example, alkyl glycol diacrylate monomers may include hexanediol diacrylate monomers.

[0111] According to another embodiment, the ink composition may optionally further contain a solvent.

[0112] There are no particular restrictions on the solvent, as long as it can uniformly disperse the quantum dots. For example, the solvent can be an organic solvent.

[0113] Specifically, the solvent may be selected from chlorine-based solvents, ether-based solvents, ester-based solvents, ketone-based solvents, aliphatic hydrocarbon-based solvents, and aromatic hydrocarbon-based solvents, but is not limited to these.

[0114] More specifically, the solvent may include dichloromethane, 1,2-dichloroethane, 1,1,2-trichloroethane, chlorobenzene, o-dichlorobenzene, or cyclohexylbenzene; tetrahydrofuran, dioxane, anisole, 4-methyl anisole, butylphenyl ether; toluene, xylene, mesitylene, ethylbenzene, n-hexylbenzene, cyclohexylbenzene, trimethylbenzene, or tetrahydronaphthalene; cyclohexane, methylcyclohexane, n-pentane, n-hexane, n-heptane, n-octane, n-nonane, n-decane, dodecane, hexadecane, or oxadecane; acetone, methyl ethyl ketone, cyclohexanone, or acetophenone; ethyl acetate, butyl acetate, methyl cellosol acetate, ethyl cellosol acetate, methyl benzoate, ethyl benzoate, butyl benzoate, 3-phenoxybenzoate, or any combination thereof, but not limited thereto.

[0115] In the ink composition, the amount of solvent can be from 80 parts by weight to 99.9 parts by weight, specifically from 90 parts by weight to 99.8 parts by weight, but not limited thereto, based on the total weight of the composition. When the above range is met, quantum dots can be suitably dispersed in the ink composition, and the ink composition can have an appropriate solids concentration in solution.

[0116] According to the embodiment, the ink composition comprising the aforementioned quantum dots can be coated onto the exterior of the light-emitting device to form an optical component. In this case, the optical component can be a color conversion component that has the function of absorbing light emitted from the light-emitting device and emitting light with different wavelength bands.

[0117] Electronic Components

[0118] The following text will describe electronic devices that incorporate the aforementioned quantum dots.

[0119] The electronic device may include quantum dots and a light-emitting device, the light-emitting device including a first electrode; a second electrode; and an intermediate layer inserted between the first electrode and the second electrode.

[0120] According to the implementation plan, the electronic device may include a liquid crystal display, an organic light-emitting display device, or an inorganic light-emitting display device.

[0121] For example, when an electronic device further includes a liquid crystal, the electronic device can be a liquid crystal display. In this case, the light-emitting device can be used as a light source, and the quantum dots can be used as color conversion components while being contained within the light-emitting device and the liquid crystal.

[0122] As another example, when the intermediate layer of a light-emitting device includes a light-emitting layer and the light-emitting layer contains organic materials, the electronic device can be an organic light-emitting display device. In this case, the light-emitting device can be used as a light source, and quantum dots can be used as color conversion components while contained outside the light-emitting device.

[0123] As another example, when the intermediate layer of a light-emitting device includes a light-emitting layer and the light-emitting layer includes an inorganic material, such as a quantum dot, the electronic device can be an inorganic light-emitting display device.

[0124] In addition to the light-emitting devices described above, the electronic device may further include a thin-film transistor. A thin-film transistor may include a source electrode, a drain electrode, and an active layer, and one of the source electrode and the drain electrode may be electrically connected to one of the first electrode and the second electrode of the light-emitting device.

[0125] Thin-film transistors may further include gate electrodes, gate insulating layers, etc.

[0126] The active layer can include crystalline silicon, amorphous silicon, organic semiconductors, oxide semiconductors, etc.

[0127] The electronic device may further include a sealing portion that encapsulates the light-emitting device. The sealing portion allows light to pass through the light-emitting device while preventing external air and moisture from penetrating it. The sealing portion may be a sealing substrate comprising a transparent glass substrate or a plastic substrate. The sealing portion may be a thin-film encapsulation layer comprising one or more organic and / or inorganic layers. When the sealing portion is a thin-film encapsulation layer, the electronic device can be flexible.

[0128] Depending on the application of the electronic device, various functional layers may be further located on the sealed portion. Examples of functional layers may include color filters, color conversion layers, touchscreen layers, and polarizing layers. The touchscreen layer may be a pressure-sensitive touchscreen layer, a capacitive touchscreen layer, or an infrared touchscreen layer.

[0129] In the following text, reference will be made to Figure 2 A detailed description of the electronic device 3, including a light-emitting device 320, according to the implementation scheme.

[0130] The electronic device 3 includes a first substrate 310, a light-emitting device 320, and a second substrate 340.

[0131] Quantum dots can be contained outside the light-emitting device 320 (i.e., on the first electrode and / or the second electrode). Specifically, quantum dots can be contained in a second substrate 340 located outside the light-emitting device 320. The second substrate 340 can be used as a color conversion component, and the light-emitting device 320 can be used as a light source.

[0132] The light-emitting device 320 includes a first electrode 321, a second electrode 323, and an intermediate layer 322 inserted between the first electrode 321 and the second electrode 323.

[0133] Electronic device 3 can be an organic light-emitting display device. Therefore, light-emitting device 320 can be included in the organic light-emitting layer in the intermediate layer 322.

[0134] A pixel defining layer 330 may be located on the first electrode 321. The pixel defining layer 330 exposes a predetermined area of ​​the first electrode 321, and an intermediate layer 322 may be located on the exposed area.

[0135] In one embodiment, a region 341 of the second substrate 340 may contain semiconductor nanoparticles. In this case, the second substrate 340 may be located in the direction of light travel emitted from the light-emitting device 320.

[0136] Quantum dots can emit visible light by absorbing blue light. Therefore, the second substrate 340 can be designed to emit light with various wavelengths by absorbing blue light. Thus, the light-emitting device 320 can emit blue light, for example, blue light with a maximum emission wavelength of 400 nm to 490 nm, and the thin film can emit visible light, for example, visible light with a maximum emission wavelength of 445 nm to 650 nm, by absorbing blue light.

[0137] In an embodiment, the second substrate 340 may further include a scatterer.

[0138] In one embodiment, the second substrate 340 further includes another region (not shown) different from the preceding region 341, and the latter region does not contain semiconductor nanoparticles and can transmit blue light emitted from the light-emitting device (not shown). Specifically, only the preceding region 341 contains semiconductor nanoparticles, while the latter region may contain only scatterers.

[0139] In an implementation, the second substrate 340 may further include a light-shielding pattern 344 between the preceding and following regions.

[0140] In the following text, reference will be made to Figure 3 Detailed description of electronic device 4 according to another embodiment.

[0141] The electronic device 4 includes a first substrate 410 and a light-emitting device 420.

[0142] The light-emitting device 420 includes a first electrode 421, a second electrode 423, and an intermediate layer 422 inserted between the first electrode 421 and the second electrode 423.

[0143] Quantum dots can be contained in the intermediate layer 422, specifically in the light-emitting layer within the intermediate layer 422.

[0144] Quantum dots can emit visible light. Therefore, the light-emitting device 420 can be designed to emit light with various wavelengths. For example, quantum dots can emit visible light with a maximum emission wavelength from 445 nm to 650 nm.

[0145] The intermediate layer 422 may further include an auxiliary layer between the light-emitting layer and the first electrode 421 and / or between the light-emitting layer and the second electrode 423. The auxiliary layer may be in direct contact with the light-emitting layer. The auxiliary layer may improve the thin film performance of the light-emitting layer.

[0146] The intermediate layer 422 may further include a first charge transport region inserted between the light-emitting layer and the first electrode 421 and / or a second charge transport region inserted between the light-emitting layer and the second electrode 423.

[0147] Methods for preparing quantum dots

[0148] The method for preparing quantum dots will be described in detail.

[0149] Methods for preparing quantum dots may include: forming a core particle using a first semiconductor compound, forming a core / shell particle comprising a shell formed of a second semiconductor by contacting the core particle with a precursor of a second semiconductor compound, and forming an outer layer on the core / shell particle.

[0150] The first semiconductor compound may contain indium (In), gallium (Ga), and phosphorus (P), and the second semiconductor compound may contain zinc (Zn), selenium (Se), and sulfur (S).

[0151] According to the implementation scheme, the second semiconductor compound precursor may comprise a first precursor and a second precursor of the second semiconductor compound. For example, the first precursor may comprise zinc (Zn) and selenium (Se), and the second precursor may comprise zinc (Zn) and sulfur (S).

[0152] According to the implementation scheme, the process of contacting the nuclear particles with the second semiconductor compound precursor may include (i) introducing the nuclear particles into a first precursor compound of the second semiconductor compound, and (ii) introducing a second precursor compound of the second semiconductor compound therein.

[0153] Operation (i) can be performed at a temperature of 290°C to 350°C (e.g., 300°C to 340°C) for 30 to 90 minutes, e.g., 50 to 70 minutes, and operation (ii) can be performed at a temperature of 290°C to 350°C (e.g., 300°C to 340°C) for 60 to 120 minutes, e.g., 80 to 100 minutes.

[0154] Therefore, composite single-layer or double-layer shells comprising two types of second semiconductor compounds can be formed on nuclear particles.

[0155] According to the implementation scheme, forming an outer layer on the core / shell particles may include setting an oligomer or polymer comprising a metal and polar organic groups on the core / shell particles. In this case, the metal is a metal constituting the second semiconductor compound, such as Zn.

[0156] In the implementation, the method may further include purification and / or separation processes after the formation of nuclear particles, and these processes may be omitted.

[0157] In the implementation scheme, the solvent can be an organic solvent. For example, the solvent can be trioctylamine, oleylamine, 1-octadecene (ODE), etc.

[0158] Details of the methods for preparing semiconductor nanoparticles can be understood by those skilled in the art by referring to the embodiments described later.

[0159]

Terminology Definition

[0160] Throughout the instruction manual, C3-C 60 A carbocyclic group refers to a cyclic group containing only 3 to 60 carbon atoms, while C1-C... 60 Heterocyclic groups are cyclic groups that contain 1 to 60 carbon atoms and further contain heteroatoms in addition to carbon atoms.

[0161] Throughout the specification, the cyclic groups include C3-C 60 Carbocyclic groups and C1-C 60 Both heterocyclic groups.

[0162] Throughout the specification, the terms "cyclic group" and "C3-C" are used. 60 Carbocyclic groups or C1-C 60 Heterocyclic groups are groups that condense into cyclic groups according to the formula used therein, i.e., monovalent or polyvalent groups (e.g., divalent, trivalent, or tetravalent groups). For example, a "phenyl group" can be a benzo[a] group, a phenyl group, or a phenylene group, which can be readily understood by those skilled in the art based on the structure containing the "phenyl group".

[0163] For example, monovalent C3-C 60Carbocyclic groups and monovalent C1-C 60 Examples of heterocyclic groups may include C3-C 10 cycloalkyl, C1-C 10 Heterocyclic alkyl, C3-C 10 Cycloalkenyl, C1-C 10 Heterocyclic alkenyl, C6-C 60 Aryl or C1-C 60 Heteroaryl groups, monovalent non-aromatic fused polycyclic groups, and monovalent non-aromatic fused heterocyclic groups, as well as divalent C3-C 60 Carbocyclic groups and divalent C1-C 60 Examples of heterocyclic groups may include C3-C 10 Cycloalkylene, C1-C 10 Heterocyclic alkyl, C3-C 10 Cycloalkylene, C1-C 10 Heterocyclic alkenyl, C6-C 60 aryl, C1-C 60 Hypoaryl groups, divalent non-aromatic fused polycyclic groups, and divalent non-aromatic fused heterocyclic groups.

[0164] Throughout the instruction manual, C1-C 60 Alkyl groups refer to monovalent groups of straight-chain or branched aliphatic hydrocarbons containing 1 to 60 carbon atoms. Examples include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, tert-pentyl, neopentyl, isopentyl, sec-pentyl, 3-pentyl, sec-isopentyl, n-hexyl, isohexyl, sec-hexyl, tert-hexyl, n-heptyl, isoheptyl, sec-heptyl, tert-heptyl, n-octyl, isooctyl, sec-octyl, tert-octyl, n-nonyl, isononyl, sec-nonyl, tert-nonyl, n-decyl, isodel, sec-decyl, and tert-decyl. Throughout the specification, C1-C 60 Alkylene refers to a group having a C1-C2 bond structure. 60 Alkyl groups are divalent groups with the same structure.

[0165] Throughout the instruction manual, C2-C 60 Alkenyl groups refer to those contained in the C2-C chain. 60 A monovalent hydrocarbon group consisting of a carbon-carbon double bond in the middle or at one end of an alkyl group, and examples thereof may include vinyl, propenyl, and butenyl. Throughout the specification, C2-C 60 Alkenyl groups refer to those with C2-C... 60 Alkenyl groups are divalent groups with the same structure.

[0166] Throughout the instruction manual, C2-C 60 The alkynyl group refers to the group contained in C2-C. 60A monovalent hydrocarbon group with a middle or one terminal carbon-carbon triple bond of an alkyl group, and examples thereof may include ethynyl and propynyl. Throughout the specification, C2-C 60 Alynyl group refers to a group that has a C2-C... 60 A divalent group with the same structure as an alkynyl group.

[0167] Throughout the instruction manual, C1-C 60 Alkoxy groups refer to those composed of -OA 101 The monovalent group represents (where A) 101 For C1-C 60 Alkyl groups, and examples thereof may include methoxy, ethoxy, and isopropoxy groups.

[0168] Throughout the instruction manual, C3-C 10 Cycloalkyl refers to a monovalent saturated hydrocarbon group containing 3 to 10 carbon atoms, and examples of cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cyclooctyl are included.

[0169] Throughout the instruction manual, C1-C 10 Heterocyclic alkyl groups refer to monovalent cyclic groups containing 1 to 10 carbon atoms and further comprising at least one heteroatom as a cyclic atom in addition to the carbon atoms. Throughout the specification, C1-C 10 Heterocyclic alkyl groups can refer to those having a C1-C2 relationship. 10 Divalent groups with the same structure as heterocyclic alkyl groups.

[0170] Throughout the instruction manual, C3-C 10 Cycloalkenyl groups are monovalent cyclic groups having 3 to 10 carbon atoms and at least one carbon-carbon double bond in the ring and lacking aromaticity. Examples include cyclopentenyl, cyclohexenyl, and cycloheptenyl. Throughout the specification, C3-C 10 Cycloalkylene refers to a group that has a C3-C... 10 A divalent group with the same structure as a cycloalkenyl group.

[0171] Throughout the instruction manual, C1-C 10 Heterocyclic alkenyl groups are monovalent cyclic groups comprising 1 to 10 carbon atoms and at least one heteroatom other than carbon atoms as cyclic atoms, and containing at least one double bond in the ring. C1-C 10 Examples of heterocyclic alkenyl groups may include 4,5-dihydro-1,2,3,4-oxarizolyl, 2,3-dihydrofuranyl, and 2,3-dihydrothiophenyl. Throughout the specification, C1-C 10 Heterocyclic alkenyl groups refer to those with C1-C... 10 Divalent groups with the same structure as heterocyclic alkenyl groups.

[0172] Throughout the instruction manual, C6-C60 Aryl refers to a monovalent group in a carbocyclic aromatic system containing 6 to 60 carbon atoms, and C6-C... 60 A aryl group is a divalent group that has a carbocyclic aromatic system containing 6 to 60 carbon atoms. (C6-C) 60 Examples of aryl groups may include phenyl groups, pentalenyl, naphthyl, azulel, indaryl, acenaphthel, phenalenyl, phenanthryl, anthracene, fluoranthracene, benzo[a]phenanthrene, pyrene, etc. Peryl, pentaphenyl, heptaphenyl, tetraphenyl, fraxyl, hexaphenyl, pentaphenyl, rubidyl, styrene, and ovoid. When C6-C 60 Aryl and C6-C 60 When an aryl group comprises two or more rings, the two or more rings can be fused.

[0173] Throughout the instruction manual, C1-C 60 A heteroaryl group refers to a monovalent group in a heterocyclic aromatic system having 1 to 60 carbon atoms and further including at least one heteroatom other than carbon atoms as a cyclic atom, and C1-C 60 A heteroaryl group is a divalent group in a heterocyclic aromatic system comprising 1 to 60 carbon atoms and at least one heteroatom other than a carbon atom as a cyclic atom. (C1-C) 60 Examples of heteroaryl groups may include pyridinyl, pyrimidinyl, pyrazinyl, pyridazinyl, triazinyl, quinolinyl, benzo[a]quinolinyl, isoquinolinyl, benzo[a]isoquinolinyl, quinoxalinyl, benzo[a]quinoxalinyl, quinazolinyl, benzo[a]quinazolinyl, cyclolinyl, phenanthrolinel, phthalazinyl, and naphthidyl. When C1-C 60 heteroaryl and C1-C 60 When a heteroaryl group comprises two or more rings, those two or more rings can fused together.

[0174] Throughout this specification, a monovalent nonaromatic fused polycyclic group refers to a monovalent group in which two or more rings are fused together, only carbon atoms are used to form the rings, and the entire molecule is nonaromatic (e.g., comprising 8 to 60 carbon atoms). Examples of monovalent nonaromatic fused polycyclic groups may include indenyl, fluorenyl, spirobisfluorenyl, benzo[a]fluorenyl, indeno[a]phenanthryl, and indeno[a]anthrayl. Throughout this specification, a divalent nonaromatic fused polycyclic group refers to a divalent group having the same structure as a monovalent nonaromatic fused polycyclic group.

[0175] Throughout the specification, a monovalent nonaromatic fused heterocyclic group refers to a monovalent group in which two or more rings are fused together, at least one heteroatom other than a carbon atom is used as a cyclic atom, and the entire molecule is nonaromatic (e.g., comprising 1 to 60 carbon atoms). Examples of monovalent non-aromatic fused heteropolycyclic groups may include: pyrrole, thiophene, furanyl, indole, benzoindole, naphthoindole, isoindole, benzoisoindole, naphthoisoindole, benzosiloxanediyl, benzothiophene, benzofuranyl, carbazole, dibenzosiloxanediyl, dibenzothiophene, dibenzofuranyl, azacarbazole, azafluorenyl, azabenzosiloxanediyl, azadibenzothiophene, azadibenzofuranyl, pyrazolyl, imidazolyl, triazolyl, tetrazolyl, oxazolyl, isoxazolyl, thiazolyl, isothiazolyl, oxadiazolyl, thiazolyl ... Diazole, benzopyrazolyl, benzoimidazolyl, benzooxazolyl, benzothiazolyl, benzooxadiazolyl, benzothiadiazolyl, imidazopyridyl, imidazopyrimidinyl, imidazotriazinyl, imidazopyrazinyl, imidazopyridazinyl, indolecarbazole, indolocarbazole, benzofuranocarbazole, benzothiophenocarbazole, benzosilicyclopentadienocarbazole, benzoindolocarbazole, benzocarbazole, benzonaphthofuranyl, benzonaphthothiophenyl, benzonaphthosilicyclopentadienyl, benzofuranodibenzofuranyl, benzofuranodibenzothiophenyl, and benzothiophenobenzothiophenyl. Throughout this specification, a divalent non-aromatic fused heteropolycyclic group refers to a divalent group having the same structure as a monovalent non-aromatic fused heteropolycyclic group.

[0176] Throughout the instruction manual, C6-C 60 Aryloxy group represents -OA 102 (where A) 102 It is C6-C 60 Aryl), and C6-C 60 Arylthioyl group represents -SA 103 (where A) 103 It is C6-C 60 Aryl).

[0177] Throughout the instruction manual, "R" 10a "can be"

[0178] Deuterium (-D), -F, -Cl, -Br, -I, hydroxyl, cyano, or nitro;

[0179] C1-C 60 Alkyl, C2-C 60 Alkenyl, C2-C 60 alkynyl or C1-C 60 Alkyl groups, which are either unsubstituted or substituted with the following groups: deuterium, -F, -Cl, -Br, -I, hydroxyl, cyano, nitro, C3-C60 Carbocyclic groups, C1-C 60 Heterocyclic groups, C6-C 60 Aryloxy group, C6-C 60 Arylthioyl, -Si(Q) 11 (Q) 12 (Q) 13 -N(Q) 11 (Q) 12 -B(Q) 11 (Q) 12 -C(=O)(Q) 11 -S(=O)2(Q) 11 -P(=O)(Q) 11 (Q) 12 (or any combination thereof);

[0180] C3-C 60 Carbocyclic groups, C1-C 60 Heterocyclic groups, C6-C 60 Aryloxy or C6-C 60 Aryl thiols, which are either unsubstituted or substituted with the following groups: deuterium, -F, -Cl, -Br, -I, hydroxyl, cyano, nitro, C1-C 60 Alkyl, C2-C 60 Alkenyl, C2-C 60 alkynyl group, C1-C 60 Alkoxy, C3-C 60 Carbocyclic groups, C1-C 60 Heterocyclic groups, C6-C 60 Aryloxy group, C6-C 60 Arylthio, -Si(Q) 21 (Q) 22 (Q) 23 -N(Q) 21 (Q) 22 -B(Q) 21 (Q) 22 -C(=O)(Q) 21 -S(=O)2(Q) 21 -P(=O)(Q) 21 (Q) 22 ), or any combination thereof; or

[0181] -Si(Q 31 (Q) 32 (Q) 33 -N(Q) 31 (Q) 32 -B(Q) 31 (Q) 32 -C(=O)(Q)31 -S(=O)2(Q) 31 ) or -P(=O)(Q 31 (Q) 32 ).

[0182] Throughout the instruction manual, Q 11 To Q 13 Q 21 To Q 23 And Q 31 To Q 33 Each of these can be independently: hydrogen; deuterium; -F; -Cl; -Br; -I; hydroxyl; cyano; nitro; C1-C 60 Alkyl; C2-C 60 Alkenyl; C2-C 60 Alkyne group; C1-C 60 Alkyl group; C3-C 60 Carbocyclic groups or C1-C 60 Heterocyclic groups, which are either unsubstituted or substituted with the following groups: deuterium, -F, cyano, C1-C 60 Alkyl, C1-C 60 Alkoxy, phenyl, nonphenyl group, or any combination thereof.

[0183] Throughout this specification, a heteroatom refers to any atom other than a carbon atom. Examples of heteroatoms may include O, S, N, P, Si, B, Ge, Se, or any combination thereof.

[0184] Throughout the specification, "Ph" stands for phenyl group, "Me" for methyl group, "Et" for ethyl group, and "ter-Bu" or "Bu" for ethyl group. t "It is tert-butyl, and "OMe" is methoxy.

[0185] Throughout the specification, "biphenyl group" refers to "a phenyl group substituted with a phenyl group." The "biphenyl group" belongs to the group with a C6-C6 configuration. 60 "Aryl" is a "substituted phenyl group" as a substituent.

[0186] Throughout the specification, "terphenyl group" refers to "a phenyl group substituted with a biphenyl group." "Terphenyl group" belongs to the group that has a C6-C... 60 Aryl-substituted C6-C 60 "Aryl" is a "substituted phenyl group" as a substituent.

[0187] Throughout this specification, unless otherwise defined, * and *' in the formula refer to the binding sites with adjacent atoms.

[0188] In the following description, compounds and light-emitting devices according to one or more embodiments of the present invention will be described in more detail with reference to the following examples.

[0189] Example

[0190] Evaluation of the quantum efficiency of InGaP-ZnSe-ZnS quantum dots before / after ligand exchange reaction

[0191] The photoluminescence quantum efficiency (PLQY) of a quantum dot dispersion containing InGaP-ZnSe-ZnS quantum dots (“Reference Example 1”) was measured using an Otsuka Electronics QE-2100 device. Subsequently, after removing impurities from the dispersion by purification (“Reference Example 2”), the photoluminescence quantum efficiency was measured in the same manner.

[0192] Subsequently, polyethylene glycol (PEG) ligands were added to a quantum dot dispersion in which InGaP-ZnSe-ZnS quantum dots were dispersed to obtain PEG-modified quantum dots (“Control 1”), wherein the surface of the InGaP-ZnSe-ZnS quantum dots was partially replaced by PEG ligands. Zn-PEG was added to a quantum dot dispersion in which the same quantum dots were dispersed to obtain Zn-PEG-modified quantum dots (“Control 2”), wherein the surface of the InGaP-ZnSe-ZnS quantum dots was partially replaced by Zn-PEG ligands.

[0193] The photoluminescence quantum efficiency of Control 1 and Control 2 was measured using a QE-2100 device.

[0194] The measured photoluminescence quantum efficiency is shown in Figure 4 middle.

[0195] refer to Figure 4 This confirmed that the quantum efficiency of Reference Example 2, which was purified once, was lower than that of Reference Example 1. In Control 1, where the surface of the quantum dots was replaced by PEG ligands, a significant decrease in quantum efficiency was confirmed. In Control 2, where the surface of the quantum dots was replaced by Zn-PEG ligands, a significant increase in quantum efficiency was confirmed compared to Control 1. In Control 2, the quantum efficiency was confirmed to be equivalent to that of the quantum dots before ligand substitution.

[0196] In the case of Reference Example 2, the decrease in quantum efficiency was thought to be due to the shedding of some metal from the quantum dots during the purification process. In the case of Control 1, the significant decrease in quantum efficiency was thought to be due to the removal of the transition metal (e.g., Zn) linked to the ligand via a ligand exchange reaction. Conversely, in the case of Control 2, the significant increase in quantum efficiency was thought to be due to the compensation of the removed transition metal (e.g., Zn) via the ligand exchange reaction by the Zn metal of the Zn-PEG ligand, thus confirming that the ligand exchange reaction is possible without a significant decrease in quantum efficiency.

[0197] Compatibility evaluation of Zn-PEG ligand substitution

[0198] The dispersibility of Control 1 and Control 2, prepared as described above, in hexanediol diacrylate (HDDA) was tested. Hexanediol diacrylate is a reactive diluent used in the quantum dot compositions. The luminescent properties after film formation can be characterized based on tests to determine whether the dispersibility of the quantum dots in HDDA is maintained.

[0199] The test was conducted by adding 5 mL of HDDA to Control 1 and Control 2 and maintaining them for 24 hours. Dispersibility was visually assessed. Results are shown below. Figure 5 In control 1, dispersion was maintained, but not in control 2.

[0200] In control 2, it was assumed that the quantum dots were not dispersed in HDDA because Zn-PEG was dissolved in it.

[0201] Calculation of ligand solubility

[0202] M-PEG5-Zn, acryloyl-PEG5-Zn, cross-linked PEG2-Zn, and cross-linked PEG3-Zn are used as examples of oligomers or polymers containing metal and polar organic groups introduced onto the quantum dot surface via ligand exchange reactions. Their R-value relative to HDDA is calculated. a The values ​​and results are shown in Table 1 below. In this regard, R was calculated using the Hansen Solubility Parameter (HSP). a The value, defined by the following equation, is R above the HDDA value. a The value indicates low solubility and high dispersibility.

[0203] R a =4x(δD 配体 -δD HDDA ) 2 +(δP 配体 -δP HDDA ) 2 +(δH 配体 -δHHDDA ) 2 ) 1 / 2

[0204] δD 配体 The energy generated by the dispersive forces between ligand molecules (unit: MPa) 0.5 );

[0205] δD HDDA The energy generated by the intermolecular dispersion forces of HDDA molecules;

[0206] δP 配体 The energy generated by the dipole intermolecular forces between ligand molecules;

[0207] δP HDDA The energy generated by the dipole intermolecular forces between HDDA molecules;

[0208] δH 配体 The energy generated by the hydrogen bonds between ligand molecules; and

[0209] δD HDDA The energy generated by the hydrogen bonds between HDDA molecules.

[0210] Table 1

[0211]

[0212]

[0213]

[0214] As shown in Table 1 above, R of acryloyl-PEG5-Zn containing acrylic acid groups a The value is higher than that of m-PEG5-Zn without acrylic groups. a Furthermore, when cross-linking groups are included, the solubility in HDDA decreases further, due to the increased R... a The value is confirmed.

[0215] Therefore, when the surface of quantum dots is covered with cross-linked Zn-PEG, quantum dots with high compatibility are expected to be prepared due to the low solubility and high dispersibility obtained by cross-linked Zn-PEG.

[0216] According to the present invention, by introducing a coating containing polar ligands into quantum dots coordinated with the surface of nonpolar ligands, not only can the dispersibility of quantum dots in polar solvents be increased without causing nonpolar ligands to detach, but the efficiency of quantum dots can also be improved by introducing the coating to suppress the loss of semiconductor metal from nonpolar ligands and quantum dots.

[0217] It should be understood that the embodiments described herein should be considered descriptive only and not for limiting purposes. The description of features or aspects of each embodiment should generally be considered applicable to other similar features or aspects in other embodiments. Although one or more embodiments have been described with reference to the accompanying drawings, those skilled in the art will understand that various changes in form and detail may be made without departing from the spirit and scope defined by the appended claims.

Claims

1. A quantum dot comprising: The core, which contains a crystal of a first semiconductor; A shell, which is located on the core and contains a crystal of at least one second semiconductor; A first region, located on the shell and containing a first ligand; and The outer layer, located on the first region, comprises an oligomer or polymer containing metal and polar organic groups, wherein... The polar organic groups include acryloyl, ether, carboxyl, epoxy, or combinations thereof. The oligomer or the polymer comprises a polymer of a monomer represented by Formula 1: <Formula 1> In Equation 1, M includes Cd, Zn, Pb, Ag, Cu, or combinations thereof. Y is a carboxyl ion group. A1 and A2 are each independently selected from unsubstituted or R-substituted products. 10a Replacement C1-C 20 Alkylene a1 and a2 are each independent integers selected from 2 to 10. When a1 is an integer of 2 or greater, two or more A1s are the same or different; and when a2 is an integer of 2 or greater, two or more A2s are the same or different. P1 and P2 are each independently selected from *-O-*' and *-S-*'. b1 and b2 are each 1. c1 and c2 are integers selected from 2 to 10. When c1 is an integer of 2 or greater, two or more *–(A1) a1 -(P1) b1 –*'same or different, and when c2 is an integer of 2 or greater, 2 or more *–(A2) a2 -(P2) b2 –*'Same or different' R 10a Selected from C1-C 20 alkyl, n is an integer selected from 1 to 5. When n is an integer of 2 or greater, 2 or more Same or different, and Z is a crosslinkable group, which includes at least one of an olefinic unsaturated group, an epoxy group, an alkoxy group, and an isocyanate group.

2. The quantum dot according to claim 1, wherein, The metal includes the same metal contained in the crystal of the second semiconductor.

3. The quantum dot according to claim 1, wherein, The polymer comprises a crosslinked polymer prepared by crosslinking the crosslinkable groups through light, heat, or crosslinking groups.

4. The quantum dot according to claim 1, wherein, The first ligand comprises C1-C 20 Hydrocarbon group.

5. The quantum dot according to claim 4, wherein, The first ligand further comprises an ionic group.

6. The quantum dot according to claim 1, wherein, The first ligand is bound to the shell via a coordination covalent bond.

7. The quantum dot according to claim 1, wherein, The first semiconductor and the second semiconductor each independently comprise: a group II-VI semiconductor compound; a group III-V semiconductor compound; a group III-VI semiconductor compound; a group I-III-VI semiconductor compound; a group IV-VI semiconductor compound; a group IV element or compound; or a combination thereof.

8. The quantum dot according to claim 1, wherein, The first semiconductor and the second semiconductor each independently comprise: CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, MgSe, MgS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnT e, CdHgS, CdHgSe, CdHgTe, HgZnS, HgZnSe, HgZnTe, MgZnSe, MgZnS, CdZnSeS, CdZnSeTe, CdZnSTe, CdHgSeS, CdHgSeTe, CdHgSTe, HgZnSeS, HgZnSeTe or HgZnSTe; GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InNP, InAlP, InNAs, InNSb, InPAs , InPSb, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, InZnP, InGaZnP or InAlZnP; GaS, GaSe, Ga2Se3, GaTe, InS, InSe, In2Se3, InTe, InGaS3 or InGaSe3, AgInS, AgInS2, CuInS, CuInS2, CuGaO2, AgGaO2 or AgAlO2; SnS, SnSe, SnTe, PbS, PbSe, PbTe, SnSeS, SnSeTe, SnSTe, PbSeS, PbSeTe, PbSTe, SnPbS, SnPbSe, SnPbTe, SnPbSSe, SnPbSeTe, SnPbSTe, Si, Ge, SiC or SiGe; Or a combination thereof.

9. The quantum dot according to claim 1, wherein, The first semiconductor comprises GaN, GaP, GaAs, GaSb, AlN, AlP, AlAs, AlSb, InN, InP, InAs, InSb, GaNP, GaNAs, GaNSb, GaPAs, GaPSb, AlNP, AlNAs, AlNSb, AlPAs, AlPSb, InGaP, InAlP, InNP, InNAs, InNSb, InPAs, InPSb, InZnP, GaAlNP, GaAlNAs, GaAlNSb, GaAlPAs, GaAlPSb, GaInNP, GaInNAs, GaInNSb, GaInPAs, GaInPSb, InAlNP, InAlNAs, InAlNSb, InAlPAs, InAlPSb, or any combination thereof, and The second semiconductor comprises CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, CdZnS, CdZnSe, CdZnTe, CdZnSeS, CdZnSeTe, CdZnSTe, or combinations thereof.

10. The quantum dot according to claim 1, wherein, The shell is a double-layered shell comprising a first shell and a second shell. The first shell is inserted between the core and the second shell.

11. The quantum dot according to claim 10, wherein, The first shell and the second shell contain crystals of different second semiconductors.

12. An ink composition comprising quantum dots according to any one of claims 1-11.

13. An optical component comprising a quantum dot according to any one of claims 1-11.

14. The optical component according to claim 13, wherein, The optical component is a color conversion component.

15. An electronic device comprising: First electrode; The second electrode faces the first electrode; An intermediate layer, which is inserted between the first electrode and the second electrode, and The color conversion component is configured to face the exterior of one or more of the first and second electrodes of the intermediate layer. The color conversion component comprises a quantum dot according to any one of claims 1-11.

16. The electronic device of claim 15, further comprising a thin-film transistor, in, The thin-film transistor includes a source electrode and a drain electrode. The first electrode of the electronic device is electrically connected to at least one of the source electrode and the drain electrode of the thin-film transistor.

Images