Semiconductor nanoparticle, method of preparing the same, and electronic device including the same

Abstract

To provide a semiconductor nanoparticle exhibiting improved optical properties.SOLUTION: Provided are a semiconductor nanoparticle, a method of preparing the same, and an electronic device including the same. In the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) is 20 or more and 40 or less, and the semiconductor nanoparticles have a quantum yield of 70% or more and 100% or less.SELECTED DRAWING: Figure 8a

Description

[Technical Field]

[0001] The present invention relates to semiconductor nanoparticles, a method for producing the same, and an electronic device including the same. [Background technology]

[0002] Semiconductor nanoparticles can exhibit characteristics that differ from bulk materials in terms of their inherent properties and known physical properties (e.g., energy band gap, melting point, etc.) For example, semiconductor nanoparticles can be configured to emit light upon energy excitation (e.g., irradiation with light or application of a voltage). Summary of the Invention [Problem to be solved by the invention]

[0003] Such luminescent nanoparticles have potential applications in a variety of devices (e.g., electronic devices). From an environmental perspective, it is desirable to develop luminescent nanoparticles that can achieve improved luminescent properties and do not contain harmful heavy metals such as cadmium. [Means for solving the problem]

[0004] One embodiment relates to semiconductor nanoparticles that exhibit enhanced optical properties.

[0005] One embodiment relates to a semiconductor nanoparticle or population thereof produced from the method.

[0006] One embodiment relates to a composition (eg, an ink composition) or a composite comprising the semiconductor nanoparticles.

[0007] One embodiment relates to a color conversion panel including the semiconductor nanoparticles.

[0008] One embodiment relates to an electronic device (for example, a display device) including the semiconductor nanoparticles or the color conversion panel.

[0009] In one embodiment, the semiconductor nanoparticles comprise silver, indium, gallium, and sulfur, wherein the molar ratio of gallium to indium (Ga / In) in the semiconductor nanoparticles is greater than or equal to 20 and less than or equal to 40, and the semiconductor nanoparticles have a quantum yield greater than or equal to 70% and less than or equal to 100%.

[0010] The semiconductor nanoparticles can include a Group 11-13-16 compound containing silver, indium, gallium, and sulfur. The semiconductor nanoparticles can include first semiconductor nanocrystals containing silver, indium, gallium, and sulfur, and second semiconductor nanocrystals containing silver, gallium, and sulfur.

[0011] In the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) may be 20.1 or more, 20.5 or more, 21 or more, or 22.5 or more. In the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) may be 23 or more. In the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) may be 40 or less, 37 or less, 35 or less, or 28 or less.

[0012] In the semiconductor nanoparticles, the molar ratio of silver to indium (Ag / In) may be 5 or more, 7 or more, 9 or more, 10 or more, 11 or more, or 13 or more and 30 or less, 25 or less, 20 or less, 18 or less, 16 or less, or 15.7 or less.

[0013] The molar ratio of sulfur to indium (S / In) in the semiconductor nanoparticles may be 31 or more, 33 or more, 37 or more and 45 or less, 42 or less, 41 or less, 38 or less, or 32 or less.

[0014] The semiconductor nanoparticles may have a molar ratio of indium to sulfur (In / S) ranging from 0.045 or less, or 0.04 or less; 0.01 or more, 0.02 or more, 0.025 or more, or 0.03 or more; or any combination thereof.

[0015] In the semiconductor nanoparticles, the molar ratio of gallium to sulfur (Ga / S) may be 0.4 or more, 0.5 or more, or 0.7 or more and 0.8 or less, 0.77 or less, or 0.75 or less.

[0016] In the semiconductor nanoparticles, the molar ratio of gallium to silver (Ga / Ag) may be 1.2 or more, 1.4 or more, 1.6 or more, or 2 or more and 2.3 or less, 2.2 or less, or 1.7 or less.

[0017] In the semiconductor nanoparticles, the molar ratio of gallium to the sum of indium and gallium (Ga / (In+Ga)) may be greater than 0.95, 0.952 or greater, 0.957 or greater, or 0.958 or greater and 0.99 or less, 0.98 or less, or 0.965 or less.

[0018] In the semiconductor nanoparticles, the molar ratio of indium to the sum of indium and gallium (In / (In+Ga)) may be less than 0.05, 0.049 or less, 0.048 or less, or 0.043 or less, and 0.011 or more, or 0.02 or more, 0.024 or more, or 0.028 or more.

[0019] In the semiconductor nanoparticles, the molar ratio of the sum of indium and gallium to silver [(In+Ga) / Ag)] may be 1.3 or more, 1.4 or more, 1.5 or more, and 2.5 or less, 2.3 or less, 1.7 or less, 1.65 or less, or 1.6 or less.

[0020] In the semiconductor nanoparticles, the molar ratio of the sum of indium and gallium to sulfur [(In+Ga) / S] may be 0.4 or more, 0.55 or more, 0.58 or more, or 0.75 or more and 0.9 or less, 0.84 or less, 0.8 or less, 0.65 or less, or 0.6 or less.

[0021] In the semiconductor nanoparticles, the molar ratio of silver to the sum of silver, indium, and gallium [Ag / (Ag+In+Ga)] may be 0.31 or more, 0.32 or more, 0.38 or more, or 0.39 or more and 0.45 or less, or 0.42 or less.

[0022] In the semiconductor nanoparticles, the molar ratio of sulfur to the sum of silver, indium, and gallium [S / (Ag+In+Ga)] may be 0.8 or more, 0.85 or more, 0.95 or more, or 1 or more and 1.12 or less, or 1.1 or less, 1.09 or less, or 1.08 or less.

[0023] The semiconductor nanoparticles may have a charge balance value, given by the formula: 0.95 or more, or 1.3 or more and 1.44 or less, or 1.35 or less, 1.1 or less, or 1.08 or less: Charge balance value = {[Ag] + 3 × ([In] + [Ga])} / 2 × [S]) where [Ag], [In], [Ga], and [S] are the molar contents of silver, indium, gallium, and sulfur, respectively, in the semiconductor nanoparticles.

[0024] The semiconductor nanoparticles can include a Group 11-13-16 compound containing silver, indium, gallium, and sulfur. The semiconductor nanoparticles can include first semiconductor nanocrystals containing silver, indium, gallium, and sulfur, and second semiconductor nanocrystals containing silver, gallium, and sulfur.

[0025] The semiconductor nanoparticles can further include zinc. The semiconductor nanoparticles can include semiconductor nanocrystals containing zinc, sulfur, and optionally gallium (e.g., third semiconductor nanocrystals or fourth semiconductor nanocrystals).

[0026] The semiconductor nanoparticles may or may not further contain sodium, and the semiconductor nanoparticles may or may not further contain lithium.

[0027] The quantum yield (e.g., absolute quantum yield) of the semiconductor nanoparticles may be 71% or more, or 75% or more and 99% or less. The absolute quantum yield of the semiconductor nanoparticles may be 71% or more, 73% or more, 75% or more, or 80% or more. The absolute quantum yield of the semiconductor nanoparticles may be in the range of 71% to 99%, 72% to 98%, or 73% to 97%.

[0028] The semiconductor nanoparticles may be configured to emit a first light. The first light may be green light. The first light may be red light.

[0029] The peak emission wavelength of the first light or the semiconductor nanoparticles may be 480 nm or more and 660 nm or less.

[0030] The emission peak wavelength of the first light or the semiconductor nanoparticles may be 500 nm or more, or 515 nm or more, and 580 nm or less, 560 nm or less, or 550 nm or less.

[0031] The emission peak wavelength of the first light or the semiconductor nanoparticles may be 600 nm or more, or 605 nm or more and 660 nm or less, or 650 nm or less.

[0032] The first light or the semiconductor nanoparticles may have a half-width of 5 nm or more, or 10 nm or more and 50 nm or less, or 45 nm or less.

[0033] The semiconductor nanoparticles may have a trap emission percentage of 20% or less, 19% or less, 18% or less, or 17% or less, as determined by the formula: Trap emission percentage (%) = [trap emission area of ​​emission spectrum / total area of ​​emission spectrum] × 100 In the above formula, the trap emission area refers to the area of ​​the region at the emission peak wavelength + 50 nm or more at a given emission peak (ie, the trap emission region).

[0034] The semiconductor nanoparticles may have a size of 7 nm or more, 7.5 nm or more, 8 nm or more and 30 nm or less, 17 nm or less, 15 nm or less, or 12 nm or less.

[0035] In one embodiment, a method for producing semiconductor nanoparticles comprises:

[0036] The method may include the steps of combining or contacting first semiconductor nanocrystals comprising silver, a Group 13 element, and a chalcogen element, a first sulfur precursor, a first gallium precursor, and optionally a silver compound in a first medium comprising an organic solvent; heating the first medium at a first reaction temperature to form intermediate particles; separating the formed intermediate particles (e.g., from the first medium); combining or contacting the separated intermediate particles, a second sulfur precursor, a second gallium precursor, and optionally a silver compound in a second medium comprising an organic solvent; and heating the second medium at a second reaction temperature to form semiconductor nanoparticles. The semiconductor nanoparticles may contain silver, indium, gallium, and sulfur, and the molar ratio of gallium to indium (Ga / In) in the semiconductor nanoparticles may be 20 or more and 40 or less. The semiconductor nanoparticles may have a quantum yield of 70% or more, 75% or more and 100% or less, or 99% or less. Details regarding the semiconductor nanoparticles are the same as those described herein.

[0037] The separated intermediate particles may be washed with a washing solvent before being added to the second medium.

[0038] The washing solvent may comprise a polar organic solvent, or a mixture thereof. The washing solvent or the polar organic solvent can include a C1 to C10 alcohol solvent, a C3 to C30 ketone solvent, a nitrile solvent, or a combination thereof. The washing solvent or the polar organic solvent may include a C1 to C10 alcohol solvent.

[0039] The first gallium precursor may include gallium bromide and optionally gallium chloride (or gallium iodide).

[0040] The second gallium precursor may include gallium bromide and optionally gallium chloride (or gallium iodide).

[0041] When the first gallium precursor or the second gallium precursor contains gallium bromide and gallium chloride (or gallium iodide), the content of gallium chloride (or gallium iodide) per mole of gallium bromide may be 0.001 moles or more, 0.01 moles or more, 0.1 moles or more, 0.3 moles or more, 0.5 moles or more, or 0.7 moles or more and 5 moles or less, 3 moles or less, 2 moles or less, 1.5 moles or less, 1 mole or less, 0.8 moles or less, 0.4 moles or less, or 0.2 moles or less.

[0042] When a silver compound (e.g., a first silver compound or a second silver compound) is present in the first medium or the second medium, the content of the silver compound (e.g., the first silver compound or the second silver compound) relative to the gallium precursor (e.g., the first gallium precursor or the second gallium precursor) may be 0.01 mol% or more, 0.1 mol% or more, 0.5 mol% or more, 1 mol% or more, or 3 mol% or more and 50 mol% or less, for example, 25 mol% or less, 10 mol% or less, or 6 mol% or less.

[0043] The silver compound (eg, the first silver compound or the second silver compound) can include a silver carboxylate, a silver acetylacetonate, a silver halide, or a combination thereof.

[0044] The first reaction temperature may be 200°C or higher, or 260°C or higher and 380°C or lower.

[0045] The second reaction temperature may be 200°C or higher, or 260°C or higher and 380°C or lower.

[0046] The first reaction temperature may be the same as or different from the second reaction temperature.

[0047] The first reaction temperature may be higher than the second reaction temperature. The first reaction temperature may be lower than the second reaction temperature. The difference between the first reaction temperature and the second reaction temperature may be 10°C or more and 50°C or less.

[0048] In one embodiment, the ink composition comprises the semiconductor nanoparticles and a liquid vehicle. The semiconductor nanoparticles may be dispersed within the liquid vehicle. The liquid vehicle may comprise a polymerizable (or liquid) monomer, an organic solvent, or a combination thereof. The ink composition may be substantially free of volatile organic solvents. The ink composition may further comprise metal oxide nanoparticles.

[0049] In one embodiment, the semiconductor nanoparticle composite includes a matrix and the semiconductor nanoparticles dispersed within the matrix. The semiconductor nanoparticle composite may be a patterned film. The semiconductor nanoparticle composite may be a sheet including first semiconductor nanoparticles that emit a first light and second semiconductor nanoparticles that emit a second light, and the first light and the second light may be different.

[0050] The semiconductor nanoparticle composite can be configured to exhibit an internal quantum efficiency or an external quantum efficiency, as defined by the following formula, of 35% or more, 38% or more, 40% or more, 42% or more, 45% or more, or 50% or more, respectively: Internal quantum efficiency (IQE, %) = [A / (B-B')] × 100 External quantum efficiency (EQE, %) = [A / B] × 100 A: Amount of first light emitted from semiconductor nanoparticles or composites B: Amount of incident light provided to the complex B': the amount of incident light that passed through the complex.

[0051] The internal quantum efficiency (or external quantum efficiency) of the semiconductor nanoparticle composite may be in the range of 36% to 100%, 37% to 98%, 39% to 96%, 41% to 92%, 43% to 90%, or a combination thereof.

[0052] The semiconductor nanoparticle composite may have a process retention rate of 75% or more, or 80% or more, defined by the following formula, when heat-treated at 180° C. for 30 minutes in a nitrogen atmosphere: Process maintenance rate (%) = [EQE (or IQE) of composite after heat treatment / EQE (or IQE) of composite before heat treatment] × 100 The process retention rate may be in the range of 77% to 130%, or 81% to 100%, or a combination thereof.

[0053] One embodiment provides a color conversion layer or color conversion structure (hereinafter simply referred to as a color conversion layer) including the semiconductor nanoparticles or a color conversion region containing the semiconductor nanoparticles. In one embodiment, the color conversion panel includes a color conversion layer including color conversion regions and, optionally, partitions (e.g., black matrix, bank, pixel defining layer, etc.) that define each region of the color conversion layer. The color conversion region includes a first region corresponding to a first pixel, and the first region includes a first composite configured to emit a first light, and the first composite includes a matrix and semiconductor nanoparticles dispersed within the matrix.

[0054] Another embodiment relates to a display device (or display panel) including a light source and the semiconductor nanoparticles (or a composite including the same, a color conversion layer, a color conversion panel, etc.). In one embodiment, the display panel may include a light-emitting panel (or light source), the color conversion panel, and optionally a light-transmitting layer located between the light-emitting panel and the color conversion panel.

[0055] The light emitting panel (or light source) can be configured to provide incident light to the color conversion layer (or color conversion panel). The incident light can include blue light and optionally green light. The blue light can have a peak wavelength in the range of 440 nm to 460 nm or 450 nm to 455 nm.

[0056] The light source may include an organic light emitting diode, a micro LED, a mini LED, an LED including nanorods, or a combination thereof.

[0057] In one embodiment, an electronic device (or a display device) includes the color conversion panel or the display panel.

[0058] In one embodiment, the display device may include a display device for an augmented reality / virtual reality device, a mobile terminal device, a monitor, a laptop computer, a television, an electronic sign, a camera, or an electrical component for a vehicle.

[0059] In one embodiment, the semiconductor nanoparticles can exhibit improved optical properties (e.g., high quantum yield and narrow half-width). In one embodiment, the semiconductor nanoparticles or polymer composites containing the same can exhibit suppressed levels of trap luminescence.

[0060] In one embodiment, the semiconductor nanoparticles or polymer composites including the same may exhibit improved process stability (eg, thermal stability and / or chemical stability). [Brief explanation of the drawings]

[0061] [Figure 1] FIG. 1 is a model view illustrating the concept of trap emission percentage. [Figure 2a] 1 is a schematic diagram illustrating a pattern formation process (photolithography method) using an ink composition according to one embodiment. [Figure 2b] 1 is a schematic diagram illustrating a pattern formation process (by an inkjet method) using an ink composition according to one embodiment. [Figure 3a] 1 is a schematic cross-sectional view of a color conversion panel according to a non-limiting embodiment. [Figure 3b] 1 is a cross-sectional view of an electronic device (display device) including a color conversion panel according to a non-limiting embodiment, where the first NPs are first semiconductor nanoparticles (e.g., green light-emitting semiconductor nanoparticles) and the second NPs are second semiconductor nanoparticles (e.g., red light-emitting semiconductor nanoparticles). [Figure 4a] 1 is a perspective view illustrating an example of a display panel including a color conversion panel according to an embodiment. [Figure 4b] FIG. 10 is an exploded view of a display element according to another embodiment. [Figure 4c] FIG. 4b is a cross-sectional view of the display panel of FIG. 4a. [Figure 4d] 10 is an exploded view of a display panel according to another embodiment. [Figure 5a] 4b is a plan view showing an example of a pixel arrangement of the display panel of FIG. 4a. FIG. [Figure 5b] FIG. 1 is a cross-sectional view showing an example of a light-emitting element. [Figure 5c] FIG. 1 is a cross-sectional view showing an example of a light-emitting element. [Figure 5d] FIG. 1 is a cross-sectional view showing an example of a light-emitting element. [Figure 5e] FIG. 1 is a cross-sectional view showing an example of a light-emitting element. [Figure 6] 5b is a cross-sectional view of the display panel of FIG. 5a taken along line IV-IV. [Figure 7a] 1 is a schematic cross-sectional view of a display element (for example, a liquid crystal display element) according to an embodiment. [Figure 7b] 1 is a schematic cross-sectional view of an electronic device (for example, an electroluminescent device) according to an embodiment. [Figure 8a] 1 shows the photoluminescence spectra of semiconductor nanoparticles produced in a comparative example and an example. [Figure 8b] 8b is an enlarged view of the trap emission portion of the photoemission spectrum of FIG. 8a. DETAILED DESCRIPTION OF THE INVENTION

[0062] The advantages and features of the technology described below, and methods for achieving them, will become more apparent with reference to the following embodiments in detail, along with the accompanying drawings. However, the embodiments are not limited to the embodiments disclosed below. Unless otherwise defined, all terms (including technical and scientific terms) used in this specification will be used in a manner commonly understood by those skilled in the art. Furthermore, terms defined in commonly used dictionaries will not be interpreted ideally or excessively unless clearly defined otherwise. Throughout the specification, when a part is said to "comprise" a certain element, this means that it can further include other elements, rather than excluding other elements, unless otherwise specified.

[0063] The thickness of the various layers and regions has been exaggerated to clearly show them in the drawings, and like parts are designated by the same reference numerals throughout the specification.

[0064] When we say that a layer, film, region, plate, or other part is "on" another part, this includes not only when it is "directly on" the other part, but also when there is another part in between. Conversely, when we say that a part is "directly on" another part, it means that there is no other part in between.

[0065] Furthermore, the singular includes the plural unless the context specifically states otherwise.

[0066] Here, the phrase "free of cadmium (or other toxic heavy metals)" can mean that the concentration of cadmium (or the heavy metal) is 100 ppm (by weight) or less, 50 ppm or less, 10 ppm or less, 1 ppm or less, 0.1 ppm or less, 0.01 ppm or less, or almost 0. In one embodiment, there is substantially no cadmium (or the heavy metal), or even if present, the amount is below the detection limit of a given detection means or at an impurity level.

[0067] Unless otherwise defined below, "substituted" means that hydrogen in the compound is replaced with a C1-C30 alkyl group, a C2-C30 alkenyl group, a C2-C30 alkynyl group, a C6-C30 aryl group, a C7-C30 alkylaryl group, a C1-C30 alkoxy group, a C1-C30 heteroalkyl group, a C3-C30 heteroalkylaryl group, a C3-C30 cycloalkyl group, a C3-C15 cycloalkenyl group, a C6-C30 cycloalkynyl group, a C2-C30 heterocycloalkyl groups, halogens (-F, -Cl, -Br or -I), hydroxyl groups (-OH), nitro groups (-NO2), cyano groups (-CN), amino groups (-NRR', where R and R' are independently hydrogen or a C1-C6 alkyl group), azido groups (-N3), amidino groups (-C(=NH)NH2), hydrazino groups (-NHNH2), hydrazono groups (=N(NH2)), aldehyde groups (-C(=O)H), carbamoyl groups group, -C(=O)NH2), a thiol group (-SH), an ester group (-C(=O)OR, where R is a C1-C6 alkyl group or a C6-C12 aryl group), a carboxyl group (-COOH) or a salt thereof (-C(=O)OM, where M is an organic or inorganic cation), a sulfonic acid group (-SOH) or a salt thereof (-SOM, where M is an organic or inorganic cation), a phosphate group (-PO3H2) or a salt thereof (-PO3MH or -PO3M2, where M is an organic or inorganic cation), and combinations thereof.

[0068] Furthermore, unless otherwise defined below, the term "hetero" means containing 1 to 3 heteroatoms selected from N, O, S, Si and P.

[0069] Additionally, "aliphatic hydrocarbon group" refers to a C1-C30 linear or branched alkyl group, a C2-C30 linear or branched alkenyl group, or a C2-C30 linear or branched alkynyl group, and "aromatic group" refers to a C6-C30 aryl group or a C2-C30 heteroaryl group.

[0070] As used herein, the term "(meth)acrylate" refers to both acrylate and / or methacrylate.

[0071] As used herein, "Group" refers to a group in the Periodic Table of the Elements.

[0072] Here, a nanostructure refers to a structure having at least one region or characteristic size on the nanoscale. In one embodiment, the size of a nanostructure may be less than about 300 nm, less than about 250 nm, less than about 150 nm, less than about 100 nm, less than about 50 nm, or less than about 30 nm. Such structures may have any shape. The nanostructures may have any shape, including but not limited to nanowires, nanorods, nanotubes, multipod-type shapes having two or more pods, nanodots (or quantum dots), etc. The nanostructures may be, for example, substantially crystalline, substantially monocrystalline, polycrystalline, amorphous, or a combination thereof.

[0073] As used herein, quantum dots refer to (e.g., semiconductor-based) nanocrystals that exhibit quantum confinement or exciton confinement and are a type of nanostructure that is luminescent (e.g., capable of emitting light upon energy excitation).

[0074] Here, the term "dispersion" can include a dispersion in which the dispersed phase is a solid and the continuous medium is a liquid or a solid different from the dispersed phase. In one embodiment, the ink composition can be in the form of a dispersion. In one embodiment, the "dispersion" can be a colloidal dispersion in which the dispersed phase has dimensions of 1 nm or more, e.g., 2 nm or more, 3 nm or more, or 4 nm or more, 10 nm or more, 50 nm or more, or 100 nm or more, and a few micrometers (μm) or less (e.g., 5 μm or less, 4 μm or less, 3 μm or less, 2 μm or less, or 1 μm or less, 900 nm or less, 800 nm or less, 700 nm or less, 600 nm or less, or 500 nm or less).

[0075] Here, the dimensions (size, thickness, etc.) may be values ​​for a single entity or averages for multiple particles. Here, the average may be the median or mean. In one embodiment, the average may be the mean.

[0076] Here, the emission peak wavelength refers to the wavelength at which the emission spectrum of given light reaches its maximum value.

[0077] As used herein, quantum efficiency and quantum yield are interchangeable terms. Here, quantum efficiency or quantum yield can be easily and reproducibly determined using commercially available devices (e.g., from Hitachi or Hamamatsu) by referring to the manual provided by the respective device manufacturer. Quantum efficiency (or quantum yield) can be measured in solution or in the solid state (in a complex).

[0078] In one embodiment, quantum efficiency (or quantum yield) is the ratio of photons emitted to photons absorbed by a nanostructure or a collection of nanostructures. In one embodiment, quantum efficiency can be measured by any method. For example, there are two methods for measuring fluorescence quantum yield or efficiency: absolute and relative. In this specification, quantum efficiency (or quantum yield) measured by the absolute method is referred to as absolute quantum efficiency (or absolute quantum yield).

[0079] In the absolute method, the fluorescence of all samples is detected through an integrating sphere to obtain the quantum efficiency. In the relative method, the fluorescence intensity of a standard dye (standard sample) is compared with that of the unknown sample to calculate the quantum efficiency of the unknown sample. Standard dyes that can be used depending on their PL wavelength include, but are not limited to, Coumarin 153, Coumarin 545, Rhodamine 101 inner salt, Anthracene, and Rhodamine 6G.

[0080] The half-width and emission peak wavelength, for example, the maximum PL (photoluminescent) peak wavelength, can be measured by a light emission spectrum obtained by a spectrophotometer such as a fluorescence spectrophotometer.

[0081] Here, the "first absorption peak wavelength" refers to the wavelength of the first main peak that appears in the lowest energy region of the UV-Vis absorption spectrum.

[0082] Semiconductor nanoparticles can also be used in various electronic devices, such as color conversion panels (or emissive color filters). Liquid crystal display devices can include a white-light-emitting backlight unit and an (absorptive) color filter, and the backlight unit can include a quantum dot sheet. In display devices including quantum dot-based color conversion panels or emissive color filters, a quantum dot layer of emissive material is disposed in front of the device, and blue light (excitation light) provided by a light source is converted into green or red light by the quantum dot layer. In color conversion panels, color conversion of incident light occurs relatively near the front of the device, achieving a wide viewing angle through omnidirectional scattering of light. Emissive color filters can reduce light loss. Color conversion panels can be electronic devices including color conversion layers or color conversion structures.

[0083] In display devices that include such color conversion panels, the physical properties (e.g., optical properties and stability) of the luminescent material can directly affect the display quality of the device. For example, the luminescent material included in the color conversion panel disposed in front of the device is required to have not only high luminous efficiency but also an improved level of absorption of excitation light. When applied to patterned single-layer films such as color filters, reduced absorption of excitation light directly causes blue leakage in the display device, adversely affecting color reproduction (e.g., DCI matching rate). The use of an absorptive color filter to prevent blue leakage can further reduce luminous efficiency. The reduced absorption of nanoparticles leads to reduced brightness of devices containing them.

[0084] Among semiconductor nanoparticles that can exhibit physical properties (optical properties and / or stability) suitable for device applications, several contain cadmium-based compounds (e.g., cadmium chalcogenides). Cadmium poses serious environmental and health problems and is a regulated element. Therefore, extensive research has been conducted on nanocrystals based on III-V compounds to develop cadmium-free, environmentally friendly nanoparticles. However, there remains a technical need for environmentally friendly nanoparticles that can exhibit increased absorption, narrower half-widths, and higher levels of luminescence efficiency than non-cadmium semiconductor nanoparticles based on III-V compounds (e.g., indium phosphide).

[0085] A display device containing a color conversion layer that uses semiconductor nanoparticles as a color conversion material may or may not include a light source (e.g., a blue light-emitting diode (LED) such as a blue LED or blue OLED) that provides relatively short-wavelength incident light. Incident light (e.g., blue light) can have higher energy (e.g., approximately 2.75 eV or less) than converted light (e.g., red, green, etc.). It may be desirable to provide a color conversion layer that can maintain its light conversion efficiency and color purity even when repeatedly irradiated with incident light. Preparation of the color conversion layer can include the formation of a composite, such as a polymer composite, or a pattern thereof containing semiconductor nanoparticles, which may involve a high-temperature process. The inventors have confirmed that when AIGS-based semiconductor nanoparticles are exposed to such high-temperature processes, they exhibit a substantial decrease in light conversion efficiency and a significant increase in trap emission (i.e., long-wavelength emission) compared to before exposure. For the use of AIGS-based semiconductor nanoparticles as a color conversion layer, it is necessary to ensure the stability of the AIGS semiconductor nanoparticles (e.g., process stability of the luminescence properties and trap emission surface).

[0086] In one embodiment, the semiconductor nanoparticles can achieve desirable luminescence properties (e.g., increased quantum yield with reduced half-width) without including cadmium and can exhibit enhanced stability.

[0087] In one embodiment, the semiconductor nanoparticles may be cadmium-free. The semiconductor nanoparticles may be mercury-free, lead-free, or a combination thereof. In one embodiment, the semiconductor nanoparticles comprise silver, indium, gallium, and sulfur (including an 11-13-16 group compound). The semiconductor nanoparticles may have a size of 2 nm or more, 5 nm or more, or 8 nm or more, and 50 nm or less, 30 nm or less, 12 nm or less, or 10 nm or less. The composition (e.g., the molar ratio or charge balance value between elements as described herein) of the 11-13-16 group compound-based semiconductor nanoparticles according to one embodiment can be adjusted as described herein to achieve improved optical properties and stability.

[0088] In one embodiment, the semiconductor nanoparticles include Ag, In, Ga, and S, or 11-13-16 group compounds containing these, and can exhibit an increased level of absorption compared to, for example, indium phosphide-based semiconductor nanoparticles. In one embodiment, the semiconductor nanoparticles exhibit increased stability, thereby maintaining or achieving desired levels of optical properties (e.g., photoconversion rate) even after relatively high-temperature processes (e.g., post-baking processes) that must be performed to form the composite. In one embodiment, the semiconductor nanoparticles are produced by the methods described herein (e.g., involving the formation and separation of intermediate particles), thereby enabling the emission of light of a desired wavelength with relatively improved efficiency even when the gallium to indium content ratio is relatively high. In one embodiment, the semiconductor nanoparticles are produced by the methods described herein and can have the composition described herein. In one embodiment, the semiconductor nanoparticles exhibit improved optical properties (e.g., high quantum yield and narrow half-width), while maintaining a desired level of luminescence efficiency and suppressing trap luminescence to a desired level even after forming a single film through a relatively high-temperature baking process.

[0089] Without intending to be bound by any particular theory, in one embodiment of the method, when a semiconductor nanocrystal layer having a high gallium content is formed, the generation of by-products (e.g., gallium oxide) that can adversely affect the physical properties of the semiconductor nanoparticles is suppressed, which is thought to contribute to ensuring improved optical properties and stability of the semiconductor nanoparticles.

[0090] Thus, in one embodiment of the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) may be 20 or greater, greater than 20, or greater than 23. In one embodiment of the semiconductor nanoparticles, the molar ratio of gallium to indium (Ga / In) may be 20.1 or greater, 20.2 or greater, 20.3 or greater, 20.4 or greater, 20.5 or greater, 20.6 or greater, 20.7 or greater, 20.8 or greater, 20.9 or greater, 21 or greater, 21.1 or greater, 21.3 or greater, 21.5 or greater, 21.7 or greater, 21.9 or greater, 22 or greater, 22.1 or greater, 22.3 or greater, 22.5 or greater, 22.7 or greater, 22.9 or greater, 23 or greater, or 23.1 or greater, 23.3 or greater, 23.5 or greater, 23.6 or greater, 23.7 or greater, 23.8 or greater, 23.9 or greater, 23.10 or greater, 23.11 or greater, 23.12 or greater, 23.13 or greater, 23.14 or greater, 23.15 or greater, 23.16 or greater, 23.17 or greater, 23.18 or greater, 23.19 or greater, 23.20 or greater, 23.21 or greater, 23.22 or greater, 23.23 or greater, 23.24 or greater, 23.25 or greater, 23.26 or greater, 23.27 or greater, 23.28 or greater, 23.29 or greater, 23.29 or greater, 23.29 or greater, 23.2 3.7 or more, or 23.9 or more; 40 or less, 38 or less, 36 or less, 35 or less, 34 or less, 33 or less, 32 or less, 31 or less, 30 or less, 29 or less, 28 or less, 27 or less, 26 or less, 25 or less, 24 or less, 23.8 or less, 23.6 or less, 23.4 or less, 23 or less, 22.8 or less, 22.6 or less, 22.4 or less, 22.2 or less, 21.8 or less, 21.6 or less, 21.4 or less, 21.2 or less, 21 or less, 20.8 or less, or 20.6 or less; or any combination thereof.

[0091] In one embodiment of the semiconductor nanoparticles, the molar ratio of silver to indium (Ag / In) is 4.9 or more, 5 or more, 5.1 or more, 5.2 or more, 5.5 or more, 5.7 or more, 5.9 or more, 6 or more, 6.5 or more, 7 or more, 7.5 or more, 8 or more, 8.5 or more, 9 or more, 9.5 or more, 10 or more, 10.4 or more, 11 or more, 11.5 or more, 11.8 or more, 12 or more, 12.5 or more, 13 or more, 13.2 or more, 13.5 or more, 13.7 or more, 13.9 or more, 14 or more, 14.5 or more, 15 or more, 15.1 or more, 15.2 or more, 15.3 or more, 16 or more, 16.5 or more, 17 or more , 17.5 or more, 18 or more, 18.5 or more, 19 or more, 19.5 or more, or 20 or more; 30 or less, 29.5 or less, 29 or less, 28 or less, 27 or less, 26 or less, 25 or less, 24 or less, 23 or less, 22 or less, 21 or less, 20 or less, 19.4 or less, 18.2 or less, 17.3 or less, 16.2 or less, 15.6 or less, 15.4 or less, 14.8 or less, 14.4 or less, 13.8 or less, 13.2 or less, 13 or less, 12.4 or less, 12.2 or less, 11.9 or less, 11.6 or less, 11.4 or less, 10.5 or less, or 10.3 or less; or any combination thereof.

[0092] The molar ratio of sulfur to indium (S / In) in the semiconductor nanoparticles can be in the range of 20 or more, 25 or more, 27 or more, 29 or more, 30 or more, 30.5 or more, 31 or more, 33 or more, 35 or more, 36 or more, 36.5 or more, 37 or more, 37.3 or more, 37.5 or more, 38 or more, or 39 or more; 48 or less, 45 or less, 42 or less, 41 or less, 40 or less, 39 or less, 38.5 or less, 37.7 or less, 36.3 or less, 35.2 or less, 34 or less, 32 or less, or 31.5 or less; or any combination thereof.

[0093] In the semiconductor nanoparticles, the molar ratio of indium to sulfur (In / S) may be in the range of 0.01 or more, 0.015 or more, 0.02 or more, 0.025 or more, or 0.03 or more; 0.1 or less, 0.07 or less, 0.05 or less, or 0.04 or less; or any combination thereof.

[0094] In the semiconductor nanoparticles, the molar ratio of gallium to sulfur (Ga / S) is 0.45 or more, 0.48 or more, 0.49 or more, 0.51 or more, 0.52 or more, 0.53 or more, 0.54 or more, 0.55 or more, 0.56 or more, 0.57 or more, 0.58 or more, 0.59 or more, 0.6 or more, 0.63 or more, 0.65 or more, 0.67 or more, 0.69 or more, 0.7 or more, 0.72 or more, 0.74 or more, 0.76 or more, or is 0.78 or greater; 1 or less, 0.95 or less, 0.9 or less, 0.85 or less, 0.8 or less, 0.79 or less, 0.78 or less, 0.77 or less, 0.75 or less, 0.73 or less, 0.71 or less, 0.7 or less, 0.69 or less, 0.68 or less, 0.65 or less, 0.64 or less, 0.61 or less, 0.6 or less, 0.56 or less, or 0.54 or less, 0.52 or less, or 0.5 or less; or any combination thereof.

[0095] The molar ratio of silver to sulfur (Ag / S) in the semiconductor nanoparticles can be in the range of 0.33 or more, 0.35 or more, 0.355 or more, 0.37 or more, 0.375 or more, 0.39 or more, 0.4 or more, or 0.41 or more; 0.5 or less, 0.45 or less, 0.44 or less, 0.43 or less, 0.42 or less, 0.41 or less, 0.4 or less, 0.39 or less, 0.38 or less, 0.36 or less, or 0.34 or less; or any combination thereof.

[0096] In the semiconductor nanoparticles, the molar ratio of gallium to silver (Ga / Ag) is 1 or more, 1.1 or more, 1.15 or more, 1.2 or more, 1.25 or more, 1.3 or more, 1.35 or more, 1.38 or more, 1.4 or more, 1.45 or more, 1.5 or more, 1.55 or more, 1.6 or more, 1.65 or more, 1.7 or more, 1.75 or more, 1.8 or more, 1.85 or more, 1.9 or more, 1.95 or more, 2 or more, or 2.05 or more. 3 or less, 2.9 or less, 2.8 or less, 2.7 or less, 2.6 or less, 2.5 or less, 2.4 or less, 2.3 or less, 2.2 or less, 2.1 or less, 2 or less, 1.9 or less, 1.8 or less, 1.75 or less, 1.7 or less, 1.65 or less, 1.6 or less, 1.58 or less, 1.56 or less, 1.52 or less, 1.48 or less, 1.46 or less, 1.44 or less, or 1.42 or less; or any combination thereof.

[0097] The semiconductor nanoparticles may have a molar ratio of gallium to the sum of indium and gallium (Ga / (In+Ga)) greater than 0.95, 0.951 or greater, 0.952 or greater, 0.953 or greater, 0.954 or greater, 0.955 or greater, 0.956 or greater, 0.957 or greater, 0.958 or greater, 0.959 or greater, or 0.96 or greater; 0.99 or less, 0.985 or less, 0.98 or less, 0.975 or less, 0.97 or less, 0.965 or less, or 0.962 or less; or any combination thereof.

[0098] In the semiconductor nanoparticles, the molar ratio of indium to the sum of indium and gallium (In / (In+Ga)) can be less than 0.05, 0.049 or less, 0.048 or less, 0.047 or less, 0.046 or less, 0.045 or less, 0.04 or less, 0.035 or less, or 0.03 or less; 0.01 or more, 0.011 or more, 0.015 or more, 0.02 or more, 0.023 or more, 0.024 or more, 0.025 or more, 0.027 or more, 0.028 or more, 0.029 or more, 0.03 or more, 0.035 or more, 0.04 or more, or 0.041 or more; or any combination thereof.

[0099] In the semiconductor nanoparticles, the total molar ratio of indium and gallium to silver ((In+Ga) / Ag) is 1.2 or more, 1.3 or more, 1.4 or more, 1.41 or more, 1.43 or more, 1.45 or more, 1.46 or more, 1.47 or more, 1.48 or more, 1.5 or more, 1.53 or more, 1.54 or more, 1.57 or more, 1.58 or more, 1.59 or more, 1.63 or more, 1.65 or more or above, 1.68 or more, 1.7 or more, 1.83 or more, 1.9 or more, 1.94 or more, 2 or more, 2.1 or more, 2.15 or more, or 2.19 or more; or 3.5 or less, 3 or less, 2.4 or less, 2.37 or less, 2.3 or less, 2.25 or less, 2.2 or less, 2 or less, 1.96 or less, 1.95 or less, 1.9 or less, 1.7 or less, or 1.62 or less; or any combination thereof.

[0100] In the semiconductor nanoparticles, the combined molar ratio of indium and gallium to sulfur [(In+Ga) / S] can be in the ranges of 0.3 or more, 0.4 or more, 0.45 or more, 0.5 or more, 0.52 or more, 0.53 or more, 0.54 or more, 0.55 or more, 0.56 or more, 0.57 or more, 0.58 or more, 0.59 or more, 0.6 or more, 0.62 or more, 0.64 or more, 0.68 or more, 0.7 or more, 0.72 or more, 0.75 or more, 0.77 or more, 0.78 or more, 0.79 or more, or 0.81 or more; 0.9 or less, 0.88 or less, 0.86 or less, 0.84 or less, 0.82 or less, 0.78 or less, 0.73 or less, 0.71 or less, 0.69 or less, 0.67 or less, 0.66 or less, or 0.65 or less; or any combination thereof.

[0101] In the semiconductor nanoparticles, the molar ratio of silver to the sum of silver, indium, and gallium [Ag / (Ag+In+Ga)] may be in the range of 0.31 or more, 0.33 or more, 0.34 or more, 0.35 or more, 0.37 or more, 0.38 or more, 0.39 or more, 0.4 or more, 0.41 or more, 0.43 or more, or 0.44 or more; 0.55 or less, 0.5 or less, 0.45 or less, 0.42 or less, 0.4 or less, 0.36 or less, 0.33 or less, 0.32 or less, or 0.28 or less; or any combination thereof.

[0102] In the semiconductor nanoparticles, the molar ratio of gallium to the total of gallium, indium, and silver (Ga / (Ga+In+Ag)) is 0.45 or more, 0.46 or more, 0.47 or more, 0.48 or more, 0.49 or more, 0.5 or more, 0.51 or more, 0.52 or more, 0.53 or more, 0.55 or more, 0.56 or more, 0.57 or more, 0.58 or more, 0.59 or more, 0.595 or more, 0.6 or more, 0.61 or more, 0. 63 or more, 0.64 or more, or 0.65 or more; 0.85 or less, 0.8 or less, 0.77 or less, 0.74 or less, 0.73 or less, 0.72 or less, 0.71 or less, 0.69 or less, 0.67 or less, 0.658 or less, 0.64 or less, 0.62 or less, 0.61 or less, 0.59 or less, 0.56 or less, 0.54 or less, 0.53 or less, 0.49 or less, or 0.485 or less; or any combination thereof.

[0103] In the semiconductor nanoparticles, the molar ratio of sulfur to the sum of silver, indium, and gallium [S / (Ag+In+Ga)] may be in the range of 0.85 or more, 0.87 or more, 0.88 or more, 0.89 or more, 0.9 or more, 0.92 or more, 0.95 or more, 1 or more, 1.02 or more, 1.03 or more, 1.04 or more, 1.05 or more, 1.06 or more, 1.07 or more, 1.08 or more, 1.09 or more, 1.1 or more, or 1.2 or more; 1.5 or less, 1.45 or less, 1.35 or less, 1.15 or less, 1.13 or less, 1.12 or less, 1.11 or less, 1.1 or less, 1.09 or less, 1.08 or less, 0.9 or less, or 0.89 or less; or any combination thereof.

[0104] The semiconductor nanoparticles may have a charge balance value of 0.95 or more, 0.98 or more, 1 or more, or 1.01 or more and 1.45 or less, 1.4 or less, 1.35 or less, 1.3 or less, 1.25 or less, 1.2 or less, 1.15 or less, 1.1 or less, 1.09 or less, 1.08 or less, 1.07 or less, 1.06 or less, or 1.05 or less, according to the formula: charge balance value={[Ag]+3×([In]+[Ga])} / 2×[S]) where [Ag], [In], [Ga], and [S] are the molar contents of silver, indium, gallium, and sulfur, respectively, in the semiconductor nanoparticles.

[0105] The semiconductor nanoparticles can further include a halogen (eg, chlorine, bromine, or a combination thereof).

[0106] In the semiconductor nanoparticles, the content of halogen (e.g., chlorine, bromine, or a combination thereof) may be 0.4 mol % to 3200 mol % or less based on indium, in other words, the content of halogen (chlorine, bromine, or a sum of these) per mole of indium may be 0.004 mol to 32 mol or less.

[0107] In the semiconductor nanoparticles, the content of halogen (e.g., chlorine, bromine, or a combination thereof) based on indium (or relative to indium, or per mole of indium) is 0.01 mol % or more (e.g., 0.0001 mol or more), 0.03 mol % or more, 0.05 mol % or more, 0.08 mol % or more, 0.1 mol % or more, 0.15 mol % or more, 0.25 mol % or more, 0.3 mol % or more, 0.35 mol % or more, 0.4 mol % or more, 0.45 mol % or more, 0.5 mol % or more, 0.6 mol % or more, 0.7 mol % or more, 0.8 mol % or more, 0.9 mol % or more, 1 mol % or more, 1.5 mol % or more, 2 mol % or more, 2.5 mol % or more, 3 mol % or more, 3. It may be 5 mol% or more, 4 mol% or more, 4.5 mol% or more, 5 mol% or more, 5.5 mol% or more, 6 mol% or more, 6.5 mol% or more, 7 mol% or more, 7.5 mol% or more, 8 mol% or more, 8.5 mol% or more, 9 mol% or more, 10 mol% or more, 13 mol% or more, 15 mol% or more, 17 mol% or more, 20 mol% or more, 25 mol% or more, 30 mol% or more, 35 mol% or more, 40 mol% or more, 45 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, 90 mol% or more, 100 mol% or more, 150 mol% or more, 200 mol% or more, 250 mol% or more, 300 mol% or more, 350 mol% or more, 400 mol% or more, or 450 mol% or more. The content of the halogen (e.g., chlorine, bromine, or a combination thereof) relative to indium (e.g., per mole of indium) is 3200 mol% or less (e.g., 32 mols or less) (Br:In 32 times), 3000 mol% or less, 2500 mol% or less, 2000 mol% or less, 1500 mol% or less, 1000 mol% or less, 900 mol% or less, 800 mol% or less, 700 mol% or less, 600 mol% or less, 500 mol% or less, % or less, 380 mol % or less, 230 mol % or less, 120 mol % or less, 110 mol % or less, 100 mol % or less, 85 mol % or less, 75 mol % or less, 65 mol % or less, 55 mol % or less, 44 mol % or less, 42 mol % or less, 37 mol % or less, 23 mol % or less, 19 mol % or less, 14 mol % or less, 7.2 mol % or less, 6.8 mol % or less, 4.3 mol % or less, 3.9 mol % or less, or 2.3 mol % or less.

[0108] In the semiconductor nanoparticles, the indium concentration may vary along the radial direction. In the semiconductor nanoparticles, the indium content in the inner portion of the particle may be different from that in the outer portion of the particle. In one embodiment, the indium content in the portion adjacent to the surface (e.g., the outermost layer or shell) may be lower than the indium content in the inner portion of the particle (or core). In one embodiment, the zinc content (concentration) in the portion adjacent to the surface (e.g., the outermost layer) may be higher than the zinc content (concentration) in the inner portion of the particle (or core). In the semiconductor nanoparticles, the zinc concentration may be higher outside than inside. The core or the first semiconductor nanocrystals may be zinc-free. In the shell, gallium may exhibit a concentration gradient that varies (e.g., higher or lower) in the radial direction (e.g., toward the surface of the particle). In the shell, the gallium concentration in the portion adjacent to the particle surface may be higher than the gallium concentration in the portion adjacent to the core.

[0109] The semiconductor nanoparticles can have a core-shell structure having a core and a shell disposed on the core. The core can include a first semiconductor nanocrystal, and the shell can include a second semiconductor nanocrystal. The shell can be a multi-layer shell, and the multi-layer shell can include a first shell layer disposed on the core, a second shell layer disposed on the first shell layer, and a third shell layer disposed on the second shell layer. The first shell layer can include the second semiconductor nanocrystal. The second shell layer or the third shell layer can include additional semiconductor nanocrystals (e.g., third semiconductor nanocrystals and / or fourth semiconductor nanocrystals) containing zinc, sulfur, and optionally gallium (including zinc chalcogenide or zinc gallium chalcogenide).

[0110] The first semiconductor nanocrystals may include silver, a Group 13 element, and a chalcogen element (or an 11-13-16 group compound including silver, a Group 13 element, and a chalcogen element). The first semiconductor nanocrystals may or may not further include zinc. The Group 13 element may include indium, gallium, or a combination thereof. The chalcogen element may include sulfur, and optionally selenium. The first semiconductor nanocrystals may include a quaternary alloy semiconductor material based on an 11-13-16 group compound including silver (Ag), indium, gallium, and sulfur. The first semiconductor nanocrystals may include silver indium gallium sulfide, for example, Ag(In x Ga 1-x )S2 (x is a number representing the molar ratio between indium and gallium, and is greater than 0 and less than 1, or 0.5). In the first semiconductor nanocrystal, the molar ratio between each component can be adjusted so that the final semiconductor nanoparticles can exhibit the desired composition and optical properties (e.g., emission peak wavelength).

[0111] In the first semiconductor nanocrystal, the molar ratio of gallium to the sum of indium and gallium may be greater than 0, or 0.1 or greater, 0.2 or greater, 0.3 or greater, 0.4 or greater, or 0.45 or greater. In the first semiconductor nanocrystal, the molar ratio of gallium to the sum of indium and gallium may be 0.55 or less, 0.5 or less, 0.49 or less, 0.45 or less, 0.42 or less, 0.33 or less, or 0.25 or less. The semiconductor nanoparticles may further comprise second semiconductor nanocrystals comprising gallium, sulfur, and optionally silver, and having a different composition from the first semiconductor nanocrystals; additional semiconductor nanocrystals (e.g., third semiconductor nanocrystals and / or fourth semiconductor nanocrystals); or combinations thereof. The second semiconductor nanocrystals may comprise a Group 13-16 compound, a Group 11-13-16 compound, or a combination thereof. The Group 13-16 compound can include gallium sulfide, gallium selenide, indium sulfide, indium selenide, indium gallium sulfide, indium gallium selenide, indium gallium selenide sulfide, or a combination thereof. The second semiconductor nanocrystals can include gallium and a chalcogen element (sulfur, and optionally selenium). The second semiconductor nanocrystals can include a ternary alloy semiconductor material containing silver, gallium, and sulfur. The molar ratio of each component in the second semiconductor nanocrystals can be adjusted so that the final semiconductor nanoparticles exhibit the desired composition and optical properties.

[0112] The additional semiconductor nanocrystals can include zinc, sulfur, and optionally gallium. In one embodiment, the third semiconductor nanocrystals can include zinc, gallium, and sulfur. The fourth semiconductor nanocrystals can include zinc and sulfur. The third semiconductor nanocrystals can include zinc gallium sulfide. The fourth semiconductor nanocrystals can include zinc sulfide.

[0113] The second semiconductor nanocrystals may cover at least a portion of the first semiconductor nanocrystals. The bandgap energy of the second semiconductor nanocrystals may be different from that of the first semiconductor nanocrystals. The bandgap energy of the second semiconductor nanocrystals may be greater than that of the first semiconductor nanocrystals. The bandgap energy of the second semiconductor nanocrystals may be less than that of the first semiconductor nanocrystals. The bandgap energy of the additional semiconductor nanocrystals (e.g., third semiconductor nanocrystals or fourth semiconductor nanocrystals) may be greater than that of the second semiconductor nanocrystals. The bandgap energy of the additional semiconductor nanocrystals (e.g., third semiconductor nanocrystals or fourth semiconductor nanocrystals) may be greater than that of the first semiconductor nanocrystals. The layer including the third semiconductor nanocrystals or the fourth semiconductor nanocrystals may be the outermost layer of the semiconductor nanoparticles.

[0114] In one embodiment, the semiconductor nanoparticles can have a core-shell structure or a core-multi-shell structure such as AgInGaS / AgGaS, AgInGaS / AgGaS / ZnGaS, AgInGaS / AgGaS / ZnS, AgInGaS / AgGaS / ZnGaS / ZnS.

[0115] The size (or average size) of the first semiconductor nanocrystals may be 0.5 nm or more, 1 nm or more, 1.5 nm or more, 1.7 nm or more, 1.9 nm or more, 2 nm or more, 2.1 nm or more, 2.3 nm or more, 2.5 nm or more, 2.7 nm or more, 2.9 nm or more, 3 nm or more, 3.1 nm or more, 3.3 nm or more, 3.5 nm or more, 3.7 nm or more, 3.9 nm or more, 4 nm or more, or 4.2 nm or more.

[0116] The size (average size) of the first semiconductor nanocrystals may be 6 nm or less, 5.5 nm or less, 5 nm or less, 4.5 nm or less, 4 nm or less, 3.5 nm or less, 3 nm or less, 2.5 nm or less, 2 nm or less, or 1.5 nm or less.

[0117] The thickness of the second semiconductor nanocrystals or the layer containing the second semiconductor nanocrystals may be 0.1 nm or more, 0.2 nm or more, or 0.3 nm or more, and the thickness of the second semiconductor nanocrystals or the layer containing the second semiconductor nanocrystals or the layer containing the second semiconductor nanocrystals may be 4 nm or less, 3.5 nm or less, 3 nm or less, 2.5 nm or less, 2 nm or less, 1.5 nm or less, 1 nm or less, or 0.8 nm or less.

[0118] When present, the third semiconductor nanocrystals or layers comprising them may have a dimension (e.g., thickness) of 0.1 nm or more, 0.3 nm or more, 0.5 nm or more, 0.7 nm or more, or 1 nm or more. The dimension (e.g., thickness) of the third semiconductor nanocrystals may be 2 nm or less, 1.5 nm or less, 1 nm or less, or 0.8 nm or less. The thickness of the third semiconductor nanocrystal layer may be in the range of 0.1 nm to 5 nm, 0.2 nm to 4 nm, 0.3 nm to 3.5 nm, 0.4 nm to 3 nm, 0.5 nm to 2.5 nm, 0.6 nm to 2 nm, 0.7 nm to 1.5 nm, 0.8 nm to 1.2 nm, 0.9 nm to 1 nm, or any combination thereof.

[0119] In one embodiment, the size or average particle size of the semiconductor nanoparticles (hereinafter simply referred to as "size") may be 1 nm or more, 1.5 nm or more, 2 nm or more, 2.5 nm or more, 3 nm or more, 3.5 nm or more, 4 nm or more, 4.5 nm or more, 5 nm or more, 5.5 nm or more, 6 nm or more, 6.5 nm or more, 7 nm or more, 7.5 nm or more, 8 nm or more, 8.5 nm or more, 9 nm or more, 9.5 nm or more, 10 nm or more, or 10.5 nm or more. The size of the semiconductor nanoparticles may be 50 nm or less, 48 ​​nm or less, 46 nm or less, 44 nm or less, 42 nm or less, 40 nm or less, 35 nm or less, 30 nm or less, 25 nm or less, 20 nm or less, 18 nm or less, 16 nm or less, 14 nm or less, 12 nm or less, 11 nm or less, 10 nm or less, 8 nm or less, 7 nm or less, 6 nm or less, or 4 nm or less.

[0120] In this specification, the size of semiconductor nanoparticles may be a particle diameter. The size of the semiconductor nanoparticles can be obtained from an image confirmed by electron microscope (e.g., transmission electron microscope) analysis. The size (e.g., diameter) of the semiconductor nanoparticles may be an equivalent diameter obtained by calculating the two-dimensional area of ​​the particle obtained from the electron microscope image by converting it into a circle. Such particle size can be easily and reproducibly determined from the microscope image using various image processing programs (e.g., ImageJ or in-house programs that can be created using coding languages). The particle size may also be a value (e.g., nominal particle size) calculated from the composition and emission peak wavelength of the semiconductor nanoparticles.

[0121] The semiconductor nanoparticles may have an average size of 5 nm or more, or 5.1 nm or more, 5.2 nm or more, and 10 nm or less, 7 nm or less, 6.5 nm or less, 6 nm or less, or 5.4 nm or less. The semiconductor nanoparticles may have a size distribution, expressed as a standard deviation, of 20% or less, 19% or less, 18% or less, 17% or less, 16% or less, 15% or less, 14% or less, 13% or less, 12% or less, 11% or less, or 10% or less of the average size. The standard deviation may be 5% or more, 10% or more, or 12% or more.

[0122] In one embodiment, semiconductor nanoparticles can be produced by the method described herein. Research has been conducted on environmentally friendly InP-based quantum dots as a light-emitting material in color conversion layer-based displays. InP-based quantum dots can include an inorganic coating layer, e.g., a shell of ZnSe or ZnS, on an indium phosphide semiconductor nanocrystal, which serves as the luminescent center. However, the relatively large volume ratio of the inorganic coating layer (i.e., the shell) in the quantum dots limits the ability to achieve a desired level of absorbance of incident light (e.g., blue light).

[0123] Semiconductor nanocrystals based on Group 11-13-16 compounds (e.g., containing silver, indium, gallium, and sulfur) can provide increased absorbance of incident light, and much research is underway in this area. Semiconductor nanoparticles can undergo a monolayer formation process for use as a color conversion material in a color conversion layer. This monolayer formation process involves contact with a monomer and high-temperature processing, e.g., 180°C or higher. However, the inventors have confirmed that this monolayer formation process can result in a substantial decrease in the optical properties (e.g., luminous efficiency) of the semiconductor nanoparticles. To prevent this substantial decrease, semiconductor nanoparticles can be formed by reacting sulfur with gallium (and optionally a silver compound) in the presence of Group 11-13-16 compound-based semiconductor nanocrystals. The semiconductor nanoparticles formed by this reaction can exhibit a significantly increased molar ratio of gallium to indium compared to Group 11-13-16 compound-based semiconductor nanocrystals, and the increased molar ratio of gallium to indium can increase particle stability. However, the inventors have determined that increasing the molar ratio of gallium to indium, for example, increasing the molar ratio of gallium to indium by 20 or more, substantially, e.g., significantly, decreases the luminescence efficiency of the resulting semiconductor nanoparticles. Without intending to be bound by theory, it is believed that as the reaction proceeds, gallium-containing by-products may adversely affect the luminescence properties of the final semiconductor nanoparticles.

[0124] In one embodiment, a method for producing semiconductor nanoparticles includes contacting a sulfur precursor and a gallium precursor (and a silver precursor) in the presence of Group 11-13-16 compound-based semiconductor nanocrystals (hereinafter referred to as first contact or first reaction) to increase the size of the semiconductor nanoparticles and form intermediate particles, separating the formed intermediate particles and washing the separated intermediate particles by selection, and contacting a sulfur precursor and a gallium precursor (and a silver precursor) in the presence of the washed intermediate particles (i.e., second contact or second reaction). The produced semiconductor nanoparticles can exhibit the characteristics described herein, for example, in a crude solution, thereby simultaneously improving stability and efficiency.

[0125] Thus, in one embodiment, the method for producing the semiconductor nanoparticles comprises: combining (or contacting) first semiconductor nanocrystals comprising silver, a Group 13 element, and a chalcogen element, a first sulfur precursor, a first gallium precursor, and optionally a first silver compound in a first medium comprising a first organic solvent; heating the first medium at a first reaction temperature (e.g., for a first reaction time) to form intermediate particles; Separating the formed intermediate particles from the first medium; and The method can include combining (or contacting) the separated intermediate particles, a second sulfur precursor, a second gallium precursor, and optionally a second silver compound in a second medium containing a second organic solvent; and heating the second medium at a second reaction temperature (e.g., for a second reaction time) to form semiconductor nanoparticles. The separated intermediate particles can be washed with a solvent before being added to the second medium.

[0126] In one embodiment, the combining or contacting step can include adding an organic ligand, the first semiconductor nanocrystals (or intermediate particles), and a first (or second) gallium precursor to a first (or second) medium. In one embodiment, the combining or contacting step can include adding a first (or second) silver compound to the first (or second) medium. The first and second media can each independently further include an organic ligand. For example, the first (or second) medium can include a first (or second) organic solvent, a first (or second) sulfur precursor, and optionally a first (or second) organic ligand.

[0127] The manufacturing method of one embodiment will be described in more detail below.

[0128] 1. Preparation of Semiconductor Nanocrystals The first semiconductor nanocrystals are as described herein. The first semiconductor nanocrystals can contain silver (Ag), indium, gallium, and sulfur. The method for producing the first semiconductor nanocrystals is not particularly limited and can be selected appropriately. In one embodiment, the first semiconductor nanocrystals can be obtained by contacting and / or reacting precursors required depending on the composition, such as a silver precursor, an indium precursor, a gallium precursor, and a sulfur precursor, in a solution containing an organic ligand and an organic solvent at a predetermined core formation reaction temperature (e.g., 180°C to 300°C or 200°C to 280°C) for a predetermined time, and then separating the precursors.

[0129] In one embodiment, the first semiconductor nanocrystals produced can be separated and optionally washed. The separation and washing can be performed by methods described herein.

[0130] In one embodiment of the method, the core-forming reaction temperature may be 120°C or higher, 180°C or higher, 190°C or higher, 200°C or higher, 205°C or higher, 210°C or higher, 220°C, 230°C, 240°C or higher, 245°C or higher, 250°C or higher, 255°C or higher, 260°C or higher, 265°C or higher, 270°C or higher, 275°C or higher, 280°C or higher, 285°C or higher, 290°C or higher, 295°C or higher, 300°C or higher, 305°C or higher, 310°C or higher, 315°C or higher, 320°C or higher, 330°C or higher, 335°C or higher, 340°C or higher, or 345°C or higher. The core formation reaction temperature may be 380°C or less, 375°C or less, 370°C or less, 365°C or less, 360°C or less, 355°C or less, 350°C or less, 340°C or less, 330°C or less, 320°C or less, 310°C or less, 300°C or less, 290°C or less, 280°C or less, 270°C or less, 260°C or less, or 250°C or less.

[0131] The core-forming reaction time is not particularly limited and can be appropriately selected taking into consideration the desired size of the first semiconductor nanocrystal, the emission wavelength of the first semiconductor nanocrystal or the final semiconductor nanoparticle, the reactivity of the precursor, and the reaction temperature. The core-forming reaction time may be 1 minute or more, 3 minutes or more, 5 minutes or more, 10 minutes or more, 20 minutes or more, or 30 minutes or more. The core-forming reaction time may be 1 minute to 2 hours, 5 minutes to 90 minutes, 10 minutes to 70 minutes, or a combination thereof.

[0132] Formation of intermediate particles The first semiconductor nanocrystals are combined (or contacted) with a first sulfur precursor, a first gallium precursor, and optionally a first silver compound in a first medium comprising a first organic solvent, and the first medium (e.g., comprising a first sulfur precursor, a first gallium precursor, and optionally a first silver compound) is heated at a first reaction temperature (e.g., for a first reaction time) to form intermediate particles.

[0133] In the method, the first medium can be pretreated (e.g., in a vacuum atmosphere). The first medium (e.g., containing a first sulfur precursor) can be pretreated in a vacuum state before adding the first semiconductor nanocrystals or the first gallium precursor. The pretreatment temperature can be lower than the first reaction temperature. The pretreatment temperature can be, for example, 20°C or higher, 25°C or higher, 80°C or higher, 100°C or higher, or 120°C or higher, and 200°C or lower, or 180°C or lower.

[0134] In one embodiment, the method can include adding the first semiconductor nanocrystals and the first gallium precursor, the first sulfur precursor, or all of them to the first (reaction) medium containing a first organic solvent (and optionally the first sulfur precursor). The method can further include adding a first silver compound to the first medium. The manner in which the first semiconductor nanocrystals, the first gallium precursor, and the first sulfur precursor are added (e.g., the order or form of addition) is not particularly limited. The first semiconductor nanocrystals can be dispersed in a suitable organic solvent and added to the reaction medium, but is not limited thereto.

[0135] The first medium (e.g., obtained after the combining) is heated at a first reaction temperature for a first reaction time to form intermediate particles. Forming the intermediate particles may include carrying out a reaction (first reaction) between a sulfur precursor and a gallium precursor (and optionally a silver compound) in the presence of the first semiconductor nanocrystals containing a Group 13 element and a chalcogen element. Without being bound by theory, the reaction may form second semiconductor nanocrystals (including gallium sulfide or silver gallium sulfide) on the first semiconductor nanocrystals, increasing the molar ratio of gallium to indium in the particles. The first medium may be a reaction medium for the first reaction.

[0136] In one embodiment, the method can include heating the first medium (comprising a first organic solvent and optionally the first sulfur precursor) under vacuum or an inert atmosphere at a first injection temperature, and adding the first semiconductor nanocrystals, the first gallium precursor, the first sulfur precursor, or a combination thereof, to the heated medium at the first injection temperature. In one embodiment, the method can include heating a reaction mixture comprising the first semiconductor nanocrystals, the first gallium precursor, the first sulfur precursor, and the first silver compound at a first reaction temperature.

[0137] The first injection temperature may be 120° C. or more, 190° C. or more, 200° C. or more, 210° C. or more, 220° C. or more, 230° C. or more, 240° C. or more, or 250° C. or more. The first injection temperature may be 280° C. or less, 275° C. or less, 270° C. or less, 265° C. or less, 260° C. or less, 255° C. or less, 250° C. or less, 240° C. or less, 230° C. or less, 220° C. or less, 210° C. or less, 200° C. or less, 190° C. or less, 180° C. or less, 170° C. or less, 160° C. or less, or 150° C. or less.

[0138] The first reaction temperature may be higher than the first injection temperature. The difference between the first injection temperature and the first reaction temperature may be 5°C or more, 10°C or more, 15°C or more, 20°C or more, 30°C or more, 40°C or more, 50°C or more, 60°C or more, 70°C or more, 80°C or more, 90°C or more, or 100°C to 200°C or less, 190°C or less, 180°C or less, 170°C or less, 160°C or less, 150°C or less, 140°C or less, 130°C or less, 120°C or less, 110°C or less, 100°C or less, 90°C or less, 80°C or less, 70°C or less, 60°C or less, 50°C or less, 40°C or less, 30°C or less, or 20°C or less.

[0139] The first reaction temperature is 210°C or higher, 220°C or higher, 230°C or higher, 240°C or higher, 245°C or higher, 250°C or higher, 255°C or higher, 260°C or higher, 265°C or higher, 270°C or higher, 275°C or higher, 280°C or higher, 285°C or higher, 290°C or higher, 295°C or higher, 300°C or higher, 305°C or higher, 310°C or higher, 315°C or higher, 320°C or higher, 330°C or higher, 335°C or higher or higher, 340°C or higher, or 345°C or higher; or 380°C or lower, 375°C or lower, 370°C or lower, 365°C or lower, 360°C or lower, 355°C or lower, 350°C or lower, 340°C or lower, 330°C or lower, 320°C or lower, 310°C or lower, 300°C or lower, 290°C or lower, 280°C or lower, 270°C or lower, 260°C or lower, or 250°C or lower; or a combination thereof. The first reaction temperature can be adjusted within the above temperature range.

[0140] The first reaction time can be appropriately controlled taking into consideration the precursor and reaction temperature, as well as the emission peak wavelength of the intermediate particles or final semiconductor nanoparticles. In one embodiment, the first reaction time may be 30 minutes or more, 35 minutes or more, 40 minutes or more, 45 minutes or more, 50 minutes or more, 55 minutes or more, 60 minutes or more, 65 minutes or more, 70 minutes or more, 75 minutes or more, 80 minutes or more, 90 minutes or more, 2 hours or more, 150 minutes or more, 3 hours or more, 190 minutes or more, 200 minutes or more, 210 minutes or more, 220 minutes or more, 230 minutes or more, 4 hours or more, 250 minutes or more, 260 minutes or more, 270 minutes or more, or 280 minutes or more. The first reaction time may be 10 hours or less, 6 hours or less, 5 hours or less, 4 hours or less, or 3 hours or less. In one embodiment, the reaction time may be 1 hour or more and 5 hours or less, 2 hours or more and 4 hours or less, or 3 hours or more and 3 hours 30 minutes or less.

[0141] The first gallium precursor may include gallium bromide and optionally gallium chloride (or gallium iodide).

[0142] The first gallium precursor or the gallium halide may contain gallium bromide and gallium chloride. In the first gallium precursor, the amount of gallium chloride per mole of gallium bromide may be 0 moles or more, 0.005 moles or more, 0.01 moles or more, 0.05 moles or more, 0.1 moles or more, or 0.15 moles or more. In the gallium precursor, the amount of gallium chloride per mole of gallium bromide may be 0.2 moles or less.

[0143] Without wishing to be bound by any particular theory, it is believed that in one embodiment of the method, employing gallium bromide as the gallium precursor (and optionally adding a silver compound as described below) can contribute to controlling the composition of the final semiconductor nanoparticles as described herein (e.g., using GaBr can suppress the trap ratio by removing excess Ag from the surface), thereby allowing the resulting final nanoparticles to exhibit enhanced stability and suppressed trap ratio relative to semiconductor nanoparticles produced by prior art techniques.

[0144] The first gallium precursor may be dispersed in a suitable organic solvent (e.g., an aromatic solvent such as toluene, an aliphatic or aromatic phosphine compound such as octadecene or TOP, or an aliphatic or aromatic phosphine oxide compound such as TOPO) and added to the first reaction medium, but is not limited thereto.

[0145] The first silver compound is added to the reaction medium in a content of 0.01 mol % or more (i.e., 0.0001 mol or more), 0.1 mol % or more (i.e., 0.001 mol or more), 0.5 mol % or more, 0.7 mol % or more, 0.9 mol % or more, 1 mol % or more, or 3 mol % or more relative to the first gallium precursor (e.g., per mole of the first gallium precursor). The content of the first silver compound may be 0.015 mol% or more, 0.1 mol% or more, 0.3 mol% or more, 0.5 mol% or more, 0.6 mol% or more, 0.7 mol% or more, 0.8 mol% or more, 0.9 mol% or more, 1 mol% or more, 1.5 mol% or more, 2 mol% or more, 2.5 mol% or more, 3 mol% or more, 3.5 mol% or more, 4 mol% or more, 4.5 mol% or more, 5 mol% or more, 5.5 mol% or more, 6 mol% or more, 6.5 mol% or more, 7 mol% or more, 7.5 mol% or more, 8 mol% or more, 8.5 mol% or more, 9 mol% or more, 9.5 mol% or more, 10 mol% or more, 11 mol% or more, 12 mol% or more, 13 mol% or more, 14 mol% or more, or 15 mol% or more, relative to the first gallium precursor. The content of the first silver compound may be 50 mol% or less, 30 mol% or less, 25 mol% or less, 20 mol% or less, 18 mol% or less, 17 mol% or less, 16 mol% or less, 15 mol% or less, 14 mol% or less, 13 mol% or less, 12 mol% or less, 11 mol% or less, 10 mol% or less, 9 mol% or less, 8 mol% or less, 7 mol% or less, 6 mol% or less, 5 mol% or less, 4 mol% or less, or 3 mol% or less, relative to the first gallium precursor. The content of the first silver compound may be 1 mol% or more, or 4.2 mol% or more and 12 mol% or less, or 8 mol% or less, relative to the first gallium precursor.

[0146] The first silver compound can include silver powder, an alkylated silver compound, a silver alkoxide, a silver carboxylate, a silver acetylacetonate, a silver nitrate, a silver sulfate, a silver halide, a silver cyanide, a silver hydroxide, a silver oxide, a silver peroxide, a silver carbonate, or a combination thereof. The first silver compound can include silver nitrate, silver acetate, silver acetylacetonate, silver chloride, silver bromide, silver fluoride, or a combination thereof.

[0147] The method of adding the first silver compound to the first (reaction) medium (e.g., the order of addition or the form of addition) is not particularly limited. The first silver compound is added in a dissolved state in an appropriate organic solvent (e.g., an organic solvent described herein, e.g., an amine-based solvent such as oleylamine, or a phosphine-based solvent such as trioctylphosphine). The timing of adding the first silver compound is also not particularly limited and can be selected appropriately. The first silver compound is added to the first (reaction) medium before or after adding the first semiconductor nanocrystals, the first gallium precursor, the first sulfur precursor, or a combination thereof. In one embodiment, the first silver compound is added to the first (reaction) medium after the pretreatment.

[0148] In one embodiment, when reacting a first gallium precursor with a first sulfur precursor in the presence of first semiconductor nanocrystals, adding a first silver compound can prevent undesired changes to the first semiconductor nanocrystals (e.g., interparticle bonding or compositional changes).

[0149] In the intermediate particle synthesis process, the amount of the first gallium precursor used relative to the first sulfur precursor can be appropriately adjusted in consideration of the composition of the final semiconductor nanoparticles, the type of precursor, the reaction temperature, and the like.

[0150] According to one embodiment of the method, the amount of the first gallium precursor used relative to the first sulfur precursor is, per mole of the first sulfur precursor, 0.5 moles or more, 0.55 moles or more, 0.6 moles or more, 0.65 moles or more, 0.7 moles or more, 0.71 moles or more, 0.75 moles or more, 0.77 moles or more, 0.8 moles or more, 0.85 moles or more, 0.9 moles or more, 0.95 moles or more, 1 mole or more, 1.05 moles or more, 1.1 moles or more, 1.12 moles or more, 1.15 moles or more, 1.2 moles or more, It may be 1.25 mol or more, 1.3 mol or more, 1.35 mol or more, 1.4 mol or more, or 1.45 mol or more; or 10 mol or less, 9.5 mol or less, 9 mol or less, 8.5 mol or less, 8 mol or less, 7.5 mol or less, 7 mol or less, 6.5 mol or less, 6 mol or less, 5.5 mol or less, 5 mol or less, 4.5 mol or less, 4 mol or less, 3.5 mol or less, 3 mol or less, 2.5 mol or less, 2 mol or less, 1.5 mol or less, 1.3 mol or less, 1 mol or less, or 0.98 mol or less.

[0151] Separation of intermediate particles and selective washing and subsequent reaction The formed intermediate particles are separated from the first medium. (After the first reaction,) a non-solvent can be added to the first reaction medium to promote precipitation of the intermediate particles (e.g., with the organic ligands coordinated thereto). The separated intermediate particles can be washed with a washing solvent before being added to the second medium. Non-solvents, precipitation, and washing are described below. The inventors surprisingly found that when semiconductor nanoparticles are produced from intermediate particles that have undergone such separation and selective washing through subsequent reactions as described below, they can have the compositions described herein and exhibit desirable optical properties (e.g., emission wavelength, increased quantum efficiency, suppressed trap emission, e.g., significantly reduced half-width) as well as improved process stability during complex formation.

[0152] The separated intermediate particles can be combined (or contacted) with a second sulfur precursor, a second gallium precursor, and optionally a second silver compound in a second medium comprising a second organic solvent, and the second medium can be heated at a second reaction temperature (e.g., for a second reaction time) to form semiconductor nanoparticles.

[0153] In the method, the second medium can be pretreated. For example, the second medium (including a second sulfur precursor) can be pretreated in a vacuum state before adding the separated intermediate particles or the second gallium precursor. The pretreatment temperature can refer to the pretreatment temperature for the first medium.

[0154] The separated intermediate particles, the second gallium precursor, the second sulfur precursor, or all of these are added to the second (reaction) medium containing a second organic solvent (and optionally the second sulfur precursor). A second silver compound is added to the second medium. The addition method (e.g., addition order or addition form) of the separated intermediate particles, the second gallium precursor, and the second sulfur precursor is not particularly limited. The separated intermediate particles may be dispersed in an appropriate organic solvent and added to the second reaction medium, but is not limited thereto.

[0155] The resulting second medium is heated at a second reaction temperature for a second reaction time to form semiconductor nanoparticles. The heating induces a reaction (second reaction) between a second sulfur precursor and a second gallium precursor (and optionally a second silver compound) in the presence of the intermediate particles. Without being bound by theory, the resulting final semiconductor nanoparticles may have a composition (e.g., a molar ratio of gallium to indium) as described herein. The second medium may be a reaction medium for the second reaction.

[0156] In one embodiment, the method can include heating the second medium (optionally containing the second sulfur precursor) under vacuum or an inert atmosphere at a second injection temperature, and adding the intermediate particles, the second gallium precursor, the second sulfur precursor, or a combination thereof to the heated medium at the second injection temperature. In one embodiment, the method can include heating a reaction mixture containing the intermediate particles, the second gallium precursor, the second sulfur precursor, and optionally the second silver compound at a second reaction temperature.

[0157] For the second injection temperature and the second reaction temperature, reference can be made to the items described for the first injection temperature and the first reaction temperature.

[0158] The second gallium precursor may include gallium bromide, gallium chloride, gallium iodide, or a combination thereof. The second gallium precursor may include gallium bromide and optionally gallium chloride (or gallium iodide). The second gallium precursor may be the same as or different from the first gallium precursor. In one embodiment, the second gallium precursor may or may not include gallium bromide. In one embodiment, the second gallium precursor may or may not include gallium chloride. In one embodiment, the second gallium precursor may or may not include gallium iodide.

[0159] In the second gallium precursor, the content of gallium chloride per mole of gallium bromide can be determined by reference to that described for the first gallium precursor.

[0160] The second gallium precursor is dispersed in a suitable organic solvent (e.g., octadecene, an aliphatic or aromatic phosphine compound such as TOP, or an aliphatic or aromatic phosphine oxide compound such as TOPO) and added to the second reaction medium, but is not limited thereto. The second silver compound may be referred to in the description of the first silver compound. In one embodiment, when the second gallium precursor and the second sulfur precursor are reacted in the presence of intermediate particles, adding the second silver compound can prevent undesired changes in the intermediate particles (e.g., particle bonding or compositional changes). According to one embodiment, a larger number of semiconductor nanoparticles can be formed in the crude solution.

[0161] The amount of the second gallium precursor used relative to the second sulfur precursor can be appropriately adjusted in consideration of the composition of the final semiconductor nanoparticles, the type of precursor, the reaction temperature, etc. According to one embodiment, the amount of the second gallium precursor used relative to the second sulfur precursor is 0.5 mol or more, 0.55 mol or more, 0.6 mol or more, 0.65 mol or more, 0.7 mol or more, 0.75 mol or more, 0.8 mol or more, 0.85 mol or more, 0.9 mol or more, 0.95 mol or more, 1 mol or more, 1.05 mol or more, 1.1 mol or more, 1.12 mol or more, 1.15 mol or more, 1.2 mol or more, 1.25 mol or more, or the like, per 1 mol of the second sulfur precursor. or more, 1.3 moles or more, 1.3 moles or more, 1.35 moles or more, 1.4 moles or more, or 1.45 moles or more; or 10 moles or less, 9.5 moles or less, 9 moles or less, 8.5 moles or less, 8 moles or less, 7.5 moles or less, 7 moles or less, 6.5 moles or less, 6 moles or less, 5.5 moles or less, 5 moles or less, 4.5 moles or less, 4 moles or less, 3.5 moles or less, 3 moles or less, 2.5 moles or less, 2 moles or less, 1.5 moles or less, 1 mole or less, or 0.98 moles or less.

[0162] The content of the second gallium precursor relative to the first gallium precursor can be selected appropriately. In one embodiment, the molar ratio of the second gallium precursor to the first gallium precursor may be 0.1 or more, 0.15 or more, 0.3 or more, 0.35 or more, 0.5 or more, 0.55 or more, 0.6 or more, 0.65 or more, 0.7 or more, 0.75 or more, 0.8 or more, 0.85 or more, 0.9 or more, or 0.95 or more. The molar ratio of the second gallium precursor to the first gallium precursor may be in the range of 0.4 to 4, 0.58 to 3, 0.63 to 2, 0.79 to 1.8, 0.9 to 1.3, 1 to 1.2, or a combination thereof.

[0163] For each mole of indium precursor added in the synthesis of the first semiconductor nanocrystal (or core), the total content of the first gallium precursor and the second gallium precursor may be 100 moles or more, 150 moles or more, 200 moles or more, 250 moles or more, 300 moles or more, 310 moles or more, 350 moles or more, 400 moles or more, 450 moles or more, 500 moles or more, 550 moles or more, 600 moles or more, 650 moles or more, 700 moles or more, 750 moles or more, 800 moles or more, 850 moles or more, 900 moles or more, 950 moles or more, 1000 moles or more, 1050 moles or more, 1100 moles or more, 1150 moles or more, or 1200 moles or more.

[0164] For each mole of indium precursor added in the synthesis of the first semiconductor nanocrystal (or core), the total content of the first gallium precursor and the second gallium precursor may be 5000 moles or less, 3000 moles or less, 2000 moles or less, 1800 moles or less, 1500 moles or less, 1080 moles or less, or 1000 moles or less.

[0165] Formation of additional semiconductor nanocrystal layers (e.g., including third or fourth semiconductor nanocrystals) In one embodiment, the method may further include the steps of: preparing an additional reaction medium containing an organic solvent and an organic ligand; heating the additional reaction medium; and contacting (reacting) a zinc precursor, a gallium precursor, and a sulfur precursor in the additional reaction medium, for example, at a reaction temperature, in the presence of a first semiconductor nanocrystal containing indium, gallium, silver, and sulfur or a particle containing the first semiconductor nanocrystal (e.g., the semiconductor nanoparticle), to form a third semiconductor nanocrystal. The third semiconductor nanocrystal may include zinc gallium sulfide (ZnGaS). Details regarding the third semiconductor nanocrystal are the same as those described herein.

[0166] The method may further include the steps of providing an additional reaction medium comprising an organic ligand in an organic solvent; heating the additional reaction medium; and contacting (e.g., reacting) a zinc precursor and a chalcogen precursor (e.g., a sulfur precursor) in the presence of the formed semiconductor nanoparticles, e.g., at a reaction temperature, to provide fourth semiconductor nanocrystals comprising a zinc chalcogenide or an outer layer comprising the same on the surface of the semiconductor nanoparticles, as described herein.

[0167] In one embodiment, the reaction temperature for forming the third semiconductor nanocrystals or the fourth semiconductor nanocrystals may be 120° C. or more, 130° C. or more, 150° C. or more, 180° C. or more, 200° C. or more, 205° C. or more, 208° C. or more and 240° C. or less, 230° C. or less, 225° C. or less, or 215° C. or less. The reaction time for forming the third semiconductor nanocrystals or the fourth semiconductor nanocrystals may be 10 minutes or more, 30 minutes or more, 40 minutes or more, 1 hour or more, 80 minutes or more, or 90 minutes or more and 5 hours or less, 4 hours or less, 3 hours or less, 2 hours or less, 90 minutes or less, or 70 minutes or less.

[0168] In one embodiment of the method, the manner in which precursors are added to the (eg, heated) reaction medium can include shot addition (eg, syringe addition), dropwise addition, or a combination thereof.

[0169] The type of silver precursor (for example, for forming the core) is not particularly limited and can be selected appropriately. The silver precursor or silver compound can include silver powder, alkylated silver compounds, silver alkoxides, silver carboxylates, silver acetylacetonates, silver nitrates, silver sulfates, silver halides, silver cyanides, silver hydroxides, silver oxides, silver peroxides, silver carbonates, or combinations thereof. The silver precursor can include silver nitrates, silver acetates, silver acetylacetonates, or combinations thereof.

[0170] The type of indium precursor (e.g., for forming the core) is not particularly limited and can be selected appropriately. The indium precursor may be indium powder, an alkylated indium compound, an indium alkoxide, an indium carboxylate, an indium nitrate, an indium percolate, an indium sulfate, an indium acetylacetonate, an indium halide, an indium cyanide, an indium hydroxide, an indium oxide, an indium peroxide, an indium carbonate, or a combination thereof. The indium precursor may include an indium carboxylate such as indium oleate or indium myristate, an indium acetate, an indium hydroxide, an indium chloride, an indium bromide, an indium iodide, or a combination thereof.

[0171] The type of sulfur precursor (e.g., first sulfur precursor or second sulfur precursor, hereinafter abbreviated as sulfur precursor) is not particularly limited and can be appropriately selected. The sulfur precursor may be an organic solvent dispersion of sulfur or a reaction product thereof (e.g., octadecene sulfide (S-ODE), trioctylphosphine sulfide (S-TOP), tributylphosphine sulfide (S-TBP), triphenylphosphine sulfide (S-TPP), trioctylamine sulfide (S-TOA)), trimethylsilyl alkyl sulfide, trimethylsilyl sulfide, mercaptopropylsilane, ammonium sulfide, sodium sulfide, C1-30 thiol compounds (e.g., alpha-toluenethiol, octanethiol, todecanethiol, etc.). The sulfur precursor may include a thiol compound, an isothiocyanate compound (e.g., cyclohexylisothiocyanate), an alkylene trithiocarbonate (e.g., ethylenetrithiocarbonate), an allyl mercaptan, a thiourea compound (e.g., dialkylthiourea having a C1 to C40 alkyl group, such as dimethylthiourea, diethylthiourea, ethylmethylthiourea, dipropylthiourea, etc.), or a combination thereof. The sulfur precursor may include a thiol compound, an isothiocyanate compound, a thiourea compound, or a combination thereof.

[0172] When present, the selenium precursor can include selenium-trioctylphosphine (Se-TOP), selenium-tributylphosphine (Se-TBP), selenium-triphenylphosphine (Se-TPP), or combinations thereof.

[0173] The type of zinc precursor is not particularly limited and can be selected appropriately. For example, the zinc precursor can include Zn metal powder, alkylated Zn compounds, Zn alkoxides, Zn carboxylates, Zn nitrates, Zn percolate, Zn sulfates, Zn acetylacetonates, Zn halides, Zn cyanides, Zn hydroxides, Zn oxides, Zn peroxides, or combinations thereof. The zinc precursor can be dimethyl zinc, diethyl zinc, zinc acetate, zinc acetylacetonates, zinc iodide, zinc bromide, zinc chloride, zinc fluoride, zinc carbonate, zinc cyanide, zinc nitrates, zinc oxides, zinc peroxides, zinc perchlorates, zinc sulfates, or the like. In one embodiment, the zinc precursor used to form the second semiconductor nanocrystals can include a Zn halide.

[0174] The type of gallium precursor used in the production of the first or additional semiconductor nanocrystals is not particularly limited and can be selected appropriately. The gallium precursor may be gallium powder, an alkylated gallium compound, a gallium alkoxide, a gallium carboxylate, a gallium nitrate, a gallium percolate, a gallium sulfate, a gallium acetylacetonate, a gallium halide, a gallium cyanide, a gallium hydroxide, a gallium oxide, a gallium peroxide, a gallium carbonate, or a combination thereof. The gallium precursor may include gallium chloride, gallium iodide, gallium bromide, gallium acetate, gallium acetylacetonate, gallium oleate, gallium palmitate, gallium stearate, gallium myristate, gallium hydroxide, or a combination thereof.

[0175] The first or second organic ligand (hereinafter simply referred to as organic ligand) can be RCOOH, RNH, RNH, RN, RSH, RHPO, RHPO, RPO, RHP, RHP, RP, ROH, RCOOR', RPO(OH), RHPOOH, or RPOOH (wherein R and R' are each independently a substituted or unsubstituted C1-C40 (or C3-C24) aliphatic hydrocarbon (e.g., an alkyl group, an alkenyl group, or an alkynyl group), or a substituted or unsubstituted C6-C40 (or C6-C24) aromatic hydrocarbon (e.g., a C6-C20 aryl group)), or a combination thereof. The organic ligand can be attached to the surface of the nanoparticles.The organic ligands include methanethiol, ethanethiol, propanethiol, butanethiol, pentanethiol, hexanethiol, heptanethiol, octanethiol, nonanethiol, decanethiol, dodecanethiol, hexadecanethiol, octadecanethiol, benzylthiol; methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, octylamine, dodecylamine, hexadecylamine, octadecylamine, dimethylamine, diethylamine, dipropylamine; methanoic acid, ethanoic acid, propanoic acid, butanoic acid, pentanoic acid, hexanoic acid, heptanoic acid, octanoic acid, dodecanoic acid, hexadecanoic acid, octadecanoic acid, oleic acid, benzoic acid; substituted or unsubstituted methylphosphines (e.g., trimethylphosphine, methyldiphenylphosphine, etc.), substituted or unsubstituted ethylphosphines (e.g., triethylphosphine, , ethyldiphenylphosphine, etc.), substituted or unsubstituted propylphosphine, substituted or unsubstituted butylphosphine, substituted or unsubstituted pentylphosphine, substituted or unsubstituted octylphosphine (e.g., trioctylphosphine (TOP)); phosphine oxides such as substituted or unsubstituted methylphosphine oxide (e.g., trimethylphosphine oxide, methyldiphenylphosphine oxide, etc.), substituted or unsubstituted ethylphosphine oxide (e.g., triethylphosphine oxide, ethyldiphenylphosphine oxide, etc.), substituted or unsubstituted propylphosphine oxide, substituted or unsubstituted butylphosphine oxide, substituted or unsubstituted octylphosphine oxide (e.g., trioctylphosphine oxide (TOPO)); diphenylphosphine, triphenylphosphine compounds, or oxide compounds thereof; phosphonic acids (phosphonic Examples of the organic ligand include, but are not limited to, C5-C20 alkyl phosphinic acids such as hexyl phosphinic acid, octyl phosphinic acid, dodecane phosphinic acid, tetradecane phosphinic acid, hexadecane phosphinic acid, and octadecane phosphinic acid, and C5-C20 alkyl phosphonic acids. The organic ligands can be used alone or in combination of two or more.

[0176] The first or second organic solvent (hereinafter referred to as organic solvent) can be selected from the group consisting of amine solvents (e.g., C1-50 aliphatic amines), nitrogen-containing heterocyclic compounds such as pyridine; C6 to C40 aliphatic hydrocarbons (e.g., alkanes, alkenes, alkynes, etc.) such as hexadecane, octadecane, octadecene, and squalene; C6 to C30 aromatic hydrocarbons such as phenyldodecane, phenyltetradecane, and phenylhexadecane; phosphines substituted with C6 to C22 alkyl groups such as trioctylphosphine; phosphine oxides substituted with C6 to C22 alkyl groups such as trioctylphosphine oxide; C12 to C22 aromatic ethers such as phenyl ether and benzyl ether, and combinations thereof. The amine solvent may be a compound having one or more (e.g., two or three) C1-50, C2-45, C3-40, C4-35, C5-30, C6-25, C7-20, C8-15, or C6-22 aliphatic hydrocarbon groups (alkyl, alkenyl, or alkynyl groups). In one embodiment, the amine solvent may include a C6-22 primary amine such as hexadecylamine or oleylamine; a C6-22 secondary amine such as dioctylamine; a C6-22 tertiary amine such as trioctylamine; or a combination thereof.

[0177] The content of the organic ligand and each precursor in the reaction medium can be appropriately selected taking into consideration the type of solvent, the type of organic ligand and each precursor, the desired particle size and composition, etc. The molar ratio between each precursor can be appropriately selected taking into consideration the desired molar ratio in the final nanoparticles and the reactivity between each precursor. The method of adding each precursor is not particularly limited. Each precursor can be injected in one or more separate injections, or in two to ten separate injections. The addition of each precursor can be carried out simultaneously or sequentially. The reaction can be carried out in an inert gas atmosphere, air, or vacuum, but is not limited thereto.

[0178] In one embodiment, the amounts of the first gallium precursor (for forming the intermediate particles) and the second gallium precursor (for the second reaction), the ratio between them, and the types of precursors and the composition of the final semiconductor nanoparticles can be appropriately selected. In one embodiment, the molar ratio of the first gallium precursor to the second gallium precursor can be, but is not limited to, 1:0.1 to 1:10, 1:0.3 to 1:3, 1:0.4 to 1:2.5, 1:0.5 to 1:2, 1:0.6 to 1:1.8, 1:0.65 to 1:1.3, 1:0.7 to 1:1.2, 1:0.8 to 1:1.1, or a combination thereof. In an embodiment method, the molar ratio of the second gallium precursor to the first gallium precursor (second gallium precursor / first gallium precursor) may be 0.1 or more, 0.15 or more, 0.2 or more, 0.25 or more, 0.3 or more, 0.35 or more, 0.4 or more, 0.45 or more, 0.5 or more, 0.55 or more, 0.6 or more, 0.64 or more, 0.7 or more, 0.76 or more, 0.8 or more, 0.81 or more, 0.9 or more, 0.91 or more, 0.94 or more, 1 or more, 1.07 or more, 1.1 or more, 1.15 or more, 1.2 or more, 1.25 or more, 1.3 or more, 1.35 or more, 1.4 or more, 1.46 or more, or 1.5 or more. In one embodiment of the method, the molar ratio of the second gallium precursor to the first gallium precursor (second gallium precursor / first gallium precursor) may be 10 or less, 3 or less, 2.5 or less, 2 or less, 1.8 or less, 1.5 or less, 1.3 or less, or 1.2 or less.

[0179] After the reaction is complete, adding a nonsolvent to the final reaction solution can separate (e.g., precipitate) the first semiconductor nanocrystals, intermediate particles, or semiconductor nanoparticles (e.g., with the organic ligand coordinated thereto). The nonsolvent can be a polar solvent that is miscible with the solvent used in the reaction but cannot disperse the nanocrystals. The nonsolvent can be determined depending on the solvent used in the reaction and can include, for example, acetone, ethanol, butanol, isopropanol, ethanediol, water, tetrahydrofuran (THF), dimethyl sulfoxide (DMSO), diethyl ether, formaldehyde, acetaldehyde, solvents with solubility parameters similar to those of the listed solvents, or combinations thereof. Separation can be performed by centrifugation, precipitation, chromatography, or distillation. The separated nanocrystals can be washed, if necessary, by adding a washing solvent. The washing solvent is not particularly limited, and a solvent with a solubility parameter similar to that of the organic solvent or the ligand can be used. Examples of non-solvents or washing solvents include, but are not limited to, C1-C10 alcohols such as ethanol, methanol, propanol, and isopropanol; C3-C30 ketone solvents such as acetone and methyl ethyl ketone; C1-C30 nitrile solvents such as acetonitrile; alkane solvents such as hexane, heptane, and octane; chloroform; aromatic solvents such as toluene and benzene; and combinations thereof. The washing solvent may be a polar solvent excluding water.

[0180] The produced semiconductor nanoparticles can be dispersed in a dispersion solvent. The produced semiconductor nanoparticles can form an organic solvent dispersion. The organic solvent dispersion may or may not contain water and / or a water-miscible organic solvent. The dispersion solvent can be selected appropriately. The dispersion solvent can include the organic solvents described above. The dispersion solvent can include a substituted or unsubstituted C1 to C40 aliphatic hydrocarbon, a substituted or unsubstituted C6 to C40 aromatic hydrocarbon, or a combination thereof.

[0181] In one embodiment, the semiconductor nanoparticles can be configured to emit green light. The emission peak wavelength of the green light can be in the range of 500 nm or more, or 505 nm or more and 580 nm or less, or 550 nm or less. The emission peak wavelength of the semiconductor nanoparticles or the green light can be 500 nm or more, 505 nm or more, 510 nm or more, 514 nm or more, 515 nm or more, 517 nm or more, 519 nm or more, 520 nm or more, 525 nm or more, 530 nm or more, 535 nm or more, 540 nm or more, or 545 nm or more; and 580 nm or less, 575 nm or less, 570 nm or less, 565 nm or less, 560 nm or less, 555 nm or less, 550 nm or less, 545 nm or less, 540 nm or less, 535 nm or less, 530 nm or less, 525 nm or less, 520 nm or less, or 515 nm or less.

[0182] In one embodiment, the semiconductor nanoparticles can be configured to emit red light, and the peak emission wavelength of the red light can be in the range of 600 nm or more, 605 nm or more, 610 nm or more, and 650 nm or less, or 640 nm or less, or 630 nm or less.

[0183] In one embodiment, the semiconductor nanoparticles may exhibit a quantum yield of 70% or greater. The quantum yield may be an absolute quantum yield. The (absolute) quantum yield may be 70% or greater, 71% or greater, 72% or greater, 73% or greater, 74% or greater, 75% or greater, 76% or greater, 77% or greater, 78% or greater, 79% or greater, 80% or greater, 81% or greater, 82% or greater, 83% or greater, 84% or greater, 85% or greater, 86% or greater, 87% or greater, 88% or greater, 89% or greater, 90% or greater, 91% or greater, 92% or greater, 93% or greater, 94% or greater, or 95% or greater. The quantum yield may be 100% or less, 99.5% or less, 99% or less, 98% or less, or 97% or less.

[0184] The semiconductor nanoparticles or the green light may have a half-width of 5 nm or more, 10 nm or more, 15 nm or more, 20 nm or more, 25 nm or more, or 30 nm or more. The half-width may be 70 nm or less, 65 nm or less, 60 nm or less, 55 nm or less, 50 nm or less, 45 nm or less, 40 nm or less, 38 nm or less, 36 nm or less, 35 nm or less, 34 nm or less, 33 nm or less, 32 nm or less, 31 nm or less, 30 nm or less, 29 nm or less, 28 nm or less, 27 nm or less, 26 nm or less, or 25 nm or less.

[0185] In one embodiment, the first light (e.g., green light or red light) may include band edge emission. In one embodiment, the light emitted by the semiconductor nanoparticles may further include defect site emission or trap emission. The band edge emission may have a smaller offset from its absorption onset energy than the trap emission and may be centered at a higher energy (lower wavelength). The band edge emission may have a narrower wavelength distribution than the trap emission. The band edge emission may have a normal (e.g., Gaussian) wavelength distribution.

[0186] In the photoemission spectrum of the semiconductor nanoparticles, the percentage of the area of ​​trap emission (T) (e.g., the portion of the emission peak that is greater than the emission peak wavelength + 50 nm) to the total area (A) of the emission peak may be 25% or less, 24% or less, 23% or less, 22% or less, 21% or less, 20% or less, 15% or less, 12% or less, 10% or less, 9% or less, 8% or less, 7% or less, 6% or less, 5% or less, 4% or less, 3% or less, or 2% or less: Trap emission percentage (%) = [T / A] × 100 In the above formula, T is the area of ​​the trap emission, A is the total area of ​​the emission peak (see Figure 1).

[0187] The present inventors have confirmed that semiconductor nanoparticles based on silver-containing Group 13-16 compounds have limitations in suppressing and eliminating trap luminescence. While providing a zinc chalcogenide layer can increase the stability of semiconductor nanoparticles, the present inventors have confirmed that the formation of the zinc chalcogenide layer can also increase the trap luminescence of the final particles. In one embodiment, the semiconductor nanoparticles, for example, by having the structure / composition described herein, can exhibit an emission spectrum in which trap luminescence is substantially suppressed or eliminated.

[0188] The shape of the produced semiconductor nanoparticles is not particularly limited, and may include, but is not limited to, for example, spherical, polyhedral, pyramidal, multipodal, or cubic shapes, nanotubes, nanowires, nanofibers, nanosheets, or combinations thereof.

[0189] The semiconductor nanoparticles thus prepared may include an organic ligand and / or an organic solvent on the surface thereof. The organic ligand and / or the organic solvent may be bound to the surface of the semiconductor nanoparticles in one embodiment. The organic ligand and the organic solvent may be the same as those described herein.

[0190] In one embodiment, the semiconductor nanoparticle composite includes a matrix and the semiconductor nanoparticles dispersed in the matrix. The semiconductor nanoparticle composite (hereinafter also referred to as the composite) may further include metal oxide fine particles. The composite may be configured to emit green light. The composite may be a patterned film. The composite may further include semiconductor nanoparticles configured to emit a second light different from the green light. The composite may be in the form of a sheet. The sheet may further include (additional) semiconductor nanoparticles configured to emit a second light different from the green light.

[0191] The semiconductor nanoparticles or the composites have improved optical properties (e.g., increased luminous efficiency and narrowed half-width) along with an increased level of blue light absorptivity (e.g., improved excitation light absorptivity), and can emit light of a desired wavelength (e.g., first light).

[0192] The composite may contain the semiconductor nanoparticles or a population thereof (e.g., at a predetermined content) and exhibit increased light absorptance. The composite may have an incident light absorptance of 70% or more, 73% or more, 75% or more, 77% or more, 80% or more, 83% or more, 85% or more, 87% or more, 90% or more, 93% or more, 94% or more, 95% or more, 96% or more, 97% or more, 98% or more, or 99% or more. The incident light absorptance of the composite may be 70% to 100%, 80% to 98%, 95% to 99%, 96% to 98%, or a combination thereof.

[0193] The absorbance of incident light can be defined as follows:

[0194] Incident light absorption rate (%) = [(B-B') / B] x 100 (%) B: The amount of incident light provided to the composite B': the amount of incident light that passed through the complex.

[0195] The composite may have a photoconversion efficiency (CE), or internal quantum efficiency, or external quantum efficiency, calculated by the following formula: 20% or more, 25% or more, 30% or more, 35% or more, 40% or more, or 45% or more: Photoconversion efficiency or internal quantum efficiency (IQE, %) = [A / (B-B')] x 100 (%) External quantum efficiency (EQE, %) = [A / B] × 100 (%) A: The amount of the first light emitted from the complex B: The amount of incident light provided to the composite B': the amount of incident light that passed through the complex.

[0196] The inventors have confirmed that, even if luminescent particles containing semiconductor nanocrystals based on Group 11-13-16 compounds achieve a desired level of optical properties, they may exhibit significantly reduced optical properties when incorporated into composites for practical device applications. The semiconductor nanoparticles of one embodiment, due to the compositional and / or structural characteristics described above, can provide composites exhibiting improved optical properties and can exhibit high optical property retention even in the form of a single film. The semiconductor nanoparticles of one embodiment can exhibit significantly improved stability (e.g., thermal stability and atmospheric stability).

[0197] Therefore, the composite including semiconductor nanoparticles of one embodiment may have a process retention rate according to the following formula of 70% or more, 75% or more, 80% or more, 85% or more, 90% or more, or 100% or more: Process maintenance rate (%)=[QE2 / QE1]×100 In the above formula, QE1 is the internal or external quantum efficiency of the semiconductor nanoparticle-polymer composite before heat treatment after polymerization, and QE2 is the internal or external quantum efficiency of the semiconductor nanoparticle-polymer composite after heat treatment.

[0198] The process retention rate may be in the range of 10 to 150%, 20 to 130%, 25 to 100%, 30 to 99%, 68 to 95%, 70 to 85%, or a combination thereof.

[0199] In one embodiment, the composite can be produced from an ink composition. The ink composition can include a liquid vehicle and (e.g., a plurality of) semiconductor nanoparticles of one embodiment. The semiconductor nanoparticles can be dispersed within the liquid vehicle.

[0200] The liquid vehicle may include a liquid monomer, an organic solvent, or a combination thereof. The ink composition may further include, or may be substantially free of, a volatile organic solvent. The ink composition may further include metal oxide nanoparticle(s) (e.g., dispersed in the liquid vehicle). The ink composition may further include a dispersant (for dispersing the semiconductor nanoparticles and / or the metal oxide nanoparticles). The dispersant may include a carboxy acid group-containing organic compound (monomer or polymer). The liquid vehicle may be free of a (e.g., volatile) organic solvent. The ink composition may be solventless.

[0201] The liquid monomer may include a (photo)polymerizable monomer containing a carbon-carbon double bond. The composition may optionally further include a (thermal or photo) initiator. The composition may be polymerized by light or heat.

[0202] The details of the nanoparticle(s) in the composition (or composite) are the same as those described herein. The content of nanoparticles in the composition (or composite) can be appropriately adjusted taking into account the desired end use (e.g., color filter, etc.). In one embodiment, the content of nanoparticles in the composition (or composite) may be 1 wt. % or more, e.g., 2 wt. % or more, 3 wt. % or more, 4 wt. % or more, 5 wt. % or more, 6 wt. % or more, 7 wt. % or more, 8 wt. % or more, 9 wt. % or more, 10 wt. % or more, 15 wt. % or more, 20 wt. % or more, 25 wt. % or more, 30 wt. % or more, 35 wt. % or more, or 40 wt. % or more, based on the solid content of the composition or composite (hereinafter, the solid content may refer to the solid content of the composition or the solid content of the composite). The content of the nanoparticles may be 70 wt. % or less, e.g., 65 wt. % or less, 60 wt. % or less, 55 wt. % or less, or 50 wt. % or less, based on the solid content. The weight percentage of a component relative to the total solid content in the composition can represent the content of the component in the composite described below.

[0203] The ink composition according to an embodiment may be a nanoparticle-containing photoresist composition that can be applied in a photolithography process. The ink composition according to an embodiment may be a composition that can provide a pattern by a printing method (e.g., a droplet ejection method such as inkjet printing). The composition according to an embodiment may not contain a conjugated (or conductive) polymer (except for the cull binder described below). The composition according to an embodiment may contain a conjugated polymer. Here, a conjugated polymer refers to a polymer having conjugated double bonds in the main chain (e.g., polyphenylene vinylene, etc.).

[0204] In one embodiment of the composition, the dispersant can ensure the dispersibility of the nanoparticles. In one embodiment, the dispersant may be a binder (or a binder polymer). The binder may include a carboxylic acid group (e.g., in a repeating unit). The binder may be an insulating polymer. The binder may be a carboxylic acid group-containing compound (monomer or polymer).

[0205] In the composition (or composite), the content of the dispersant may be, but is not limited to, 0.5% by weight or more, for example, 1% by weight or more, 5% by weight or more, 10% by weight or more, 15% by weight or more, or 20% by weight or more, based on the total solid content of the composition (or composite).The content of the dispersant may be 55% by weight or less, 35% by weight or less, 33% by weight or less, or 30% by weight or less, based on the total solid content.

[0206] In the composition (or liquid vehicle), the liquid monomer or the polymerizable (e.g., photopolymerizable) monomer containing a carbon-carbon double bond (hereinafter referred to as "monomer") may include a (e.g., photopolymerizable) (meth)acrylic monomer. The monomer may be a precursor for an insulating polymer.

[0207] The content of the monomer may be 0.5 wt % or more, for example, 1 wt % or more, 2 wt % or more, 3 wt % or more, 5 wt % or more, or 10 wt % or more, based on the total weight or total solids of the composition. The content of the photopolymerizable monomer may be 30 wt % or less, for example, 28 wt % or less, 25 wt % or less, 23 wt % or less, 20 wt % or less, 18 wt % or less, 17 wt % or less, 16 wt % or less, or 15 wt % or less, based on the total weight of the composition.

[0208] The (photo)initiator contained in the composition is for (photo)polymerization of the above-mentioned monomer. The initiator is a compound that can generate radical chemical species under mild conditions (e.g., by heat or light) to promote a radical reaction (e.g., radical polymerization of a monomer). The initiator may be a thermal initiator or a photoinitiator. The initiator is not particularly limited and can be selected appropriately.

[0209] The content of the initiator in the composition can be appropriately adjusted taking into consideration the type and content of the polymerizable monomer used. In one embodiment, the content of the initiator may be, but is not limited to, 0.01 wt % or more, for example, 1 wt % or more, and 10 wt % or less, for example, 9 wt % or less, 8 wt % or less, 7 wt % or less, 6 wt % or less, or 5 wt % or less, based on the total weight of the composition (or the total weight of the solid content).

[0210] The composition (or composite) can further comprise a (multi- or monofunctional) thiol compound having at least one terminal thiol group (or a residue derived therefrom, such as a residue formed by the reaction between a thiol and a carbon-carbon double bond, e.g., a sulfide group), a metal oxide particulate, or a combination thereof.

[0211] The metal oxide fine particles can include TiO2, SiO2, BaTiO3, Ba2TiO4, ZnO, or a combination thereof. The content of the metal oxide in the composition (or composite) can be 1 wt% or more, 2 wt% or more, 3 wt% or more, 5 wt% or more, or 10 wt% or more and 50 wt% or less, 40 wt% or less, 30 wt% or less, 25 wt% or less, 20 wt% or less, 15 wt% or less, 10 wt% or less, 7 wt% or less, 5 wt% or less, or 3 wt% or less, based on the total solid content.

[0212] The diameter of the metal oxide fine particles is not particularly limited and can be selected appropriately. The diameter of the metal oxide fine particles may be 100 nm or more, for example, 150 nm or more or 200 nm or more, and 1000 nm or less, or 800 nm or less.

[0213] The multiple thiol compound may be a dithiol compound, a trithiol compound, a tetrathiol compound, or a combination thereof. For example, the thiol compound may be glycol di-3-mercaptopropionate, glycol dimercaptoacetate, trimethylolpropane tris(3-mercaptopropionate), pentaerythritol tetrakis(3-mercaptopropionate), pentaerythritol tetrakis(2-mercaptoacetate), 1,6-hexanedithiol, 1,3-propanedithiol, 1,2-ethanedithiol, polyethylene glycol dithiol containing 1 to 10 ethylene glycol repeating units, or a combination thereof.

[0214] The content of the thiol compound (or a residue derived therefrom) may be 50% by weight or less, 40% by weight or less, 30% by weight or less, 20% by weight or less, 10% by weight or less, 9% by weight or less, 8% by weight or less, 7% by weight or less, 6% by weight or less, or 5% by weight or less, based on the total solid content. The content of the thiol compound may be 0.1% by weight or more, for example, 0.5% by weight or more, 1% by weight or more, 5% by weight or more, 10% by weight or more, 15% by weight or more, 18% by weight or more, or 20% by weight or more, based on the total solid content.

[0215] The composition or the liquid vehicle may contain an organic solvent. The composition or the liquid vehicle may not contain an organic solvent. If an organic solvent is present, the type of solvent that can be used is not particularly limited. The type and amount of the organic solvent are appropriately determined taking into account the types and amounts of the main components described above (i.e., nanoparticles, dispersant, polymerizable monomer, initiator, and thiol compound, if present) and other additives described below. The composition contains the solvent in an amount that is the remainder of the desired solid content (non-volatile content). In one embodiment, examples of the organic solvent include ethylene glycols; glycol ethers; glycol ether acetates; propylene glycols; propylene glycol ethers; propylene glycol ether acetates; amides such as N-methylpyrrolidone, dimethylformamide, and dimethylacetamide; ketones such as methyl ethyl ketone (MEK), methyl isobutyl ketone (MIBK), and cyclohexanone; petroleums such as toluene, xylene, and solvent naphtha; esters such as ethyl acetate, butyl acetate, and ethyl lactate; ethers such as diethyl ether, dipropyl ether, and dibutyl ether; chloroform, C1 to C40 aliphatic hydrocarbons (e.g., alkane, alkene, or alkyne), a halogen (e.g., chloro)-substituted C1 to C40 aliphatic hydrocarbons (e.g., dichloroethane, trichloromethane, or the like), C6 to C40 aromatic hydrocarbons (e.g., toluene, xylene, or the like), and halogen (e.g., chloro)-substituted C6 to C40 aromatic hydrocarbons.

[0216] In addition to the above-described components, the composition (or composite) may further contain various additives, such as a light diffusing agent, a leveling agent, a coupling agent, etc. The components (binder, monomer, solvent, additive, thiol compound, cull binder, etc.) contained in the composition of one embodiment may be selected as appropriate, and the specific contents thereof may be found in, for example, US-2017-0052444-A1.

[0217] The composition according to one embodiment is prepared by mixing the above-mentioned components sequentially or simultaneously, and the order of mixing is not particularly limited.

[0218] The composition can be polymerized (e.g., radically) to provide a color conversion layer (or a patterned film of the composite). The color conversion layer (or a patterned film of the composite) can be fabricated using a photoresist composition. This method includes the steps of (S1) forming a film of the composition on a substrate; (S2) selectively prebaking the film; (S3) exposing selected areas of the film to light (e.g., with a wavelength of 400 nm or less); and (S4) developing the exposed film with an alkaline developer to obtain a pattern of the quantum dot-polymer composite.

[0219] Referring to Figure 2a, the composition is applied to a substrate to a predetermined thickness using a suitable method such as spin coating or slit coating to form a film. The formed film may optionally be pre-baked (PRB). The pre-baking conditions, such as temperature, time, and atmosphere, are well known and can be selected appropriately.

[0220] The formed (or optionally pre-baked) film is exposed to light of a predetermined wavelength through a mask having a predetermined pattern. The wavelength and intensity of the light can be selected taking into account the type and content of the photoinitiator, the type and content of the quantum dots, etc.

[0221] When the exposed film is treated with an alkaline developer (e.g., immersion or spraying), the unexposed portions of the film dissolve, yielding the desired pattern. If necessary, the resulting pattern can be post-baked (POB) at a temperature of 150°C to 230°C for a predetermined time (e.g., 10 minutes or more, or 20 minutes or more) to improve the crack resistance and solvent resistance of the pattern.

[0222] When the color conversion layer or patterned film of the nanoparticle composite has multiple repeating sections (i.e., color conversion regions), multiple compositions containing quantum dots (e.g., red-emitting quantum dots, green quantum dots, or optionally blue quantum dots) with desired luminescent properties (e.g., light-emitting peak wavelength) are prepared for each repeating section, and the above-described patterning process is repeated for each composition as many times as necessary (e.g., two or more times, or three or more times) to obtain the desired pattern of nanoparticle-polymer composite. For example, the nanoparticle-polymer composite may have a pattern in which two or more different color sections (e.g., RGB color sections) are repeated. Such nanoparticle-polymer composite patterns can be advantageously used as light-emitting color filters in display devices.

[0223] A color conversion layer or a patterned film of nanoparticle composites can be fabricated using an ink composition configured to form a pattern using an inkjet method. Referring to FIG. 2b, such a method can include the steps of preparing an ink composition, providing a substrate (e.g., on which pixel regions are patterned, e.g., electrodes and, optionally, banks or trench-type partitions), and depositing the ink composition on the substrate (or the pixel regions) to form, for example, a first composite layer (or a first region). The method can also include the step of depositing an ink composition on the substrate (or the pixel regions) to form, for example, a second composite layer (or a second region). The formation of the first composite layer and the formation of the second composite layer can be performed simultaneously or sequentially.

[0224] The ink composition can be deposited using a suitable liquid crystal ejection device, such as an inkjet or nozzle printing system (e.g., having an ink reservoir and one or more print heads). The deposited ink composition can be heated to remove the solvent and polymerize to provide a (first or second) composite layer. This method allows for the formation of highly accurate nanoparticle-polymer composite films or patterned membranes in a simple manner and in a short time.

[0225] In one embodiment of the composite (e.g., the first composite), the (polymer) matrix can include the components described above in connection with the composition. The matrix content in the composite can be 10% by weight or more, 20% by weight or more, 30% by weight or more, 40% by weight or more, 50% by weight or more, or 60% by weight or more, based on the total weight of the composite. The matrix content can be 95% by weight or less, 90% by weight or less, 80% by weight or less, 70% by weight or less, 60% by weight or less, or 50% by weight or less, based on the total weight of the composite.

[0226] The (polymer) matrix may include at least one of a dispersant (e.g., a carboxy acid group-containing binder polymer), a polymerization product (e.g., an insulating polymer) of a polymerizable monomer containing one or more carbon-carbon double bonds (e.g., two or more, three or more, four or more, or five or more), and a polymerization product between the polymerizable monomer and a multi-thiol compound having at least two thiol groups at its terminals. The matrix may include a linear polymer, a cross-linked polymer, or a combination thereof. The (polymer) matrix may not include a conjugated polymer (except for cardo resins). The matrix may include a conjugated polymer.

[0227] The crosslinked polymer may comprise a thiol-ene resin, a crosslinked poly(meth)acrylate, a crosslinked polyurethane, a crosslinked epoxy resin, a crosslinked vinyl polymer, a crosslinked silicone resin, or a combination thereof. In one embodiment, the crosslinked polymer may be the polymerization product of the aforementioned polymerizable monomers and optionally a multi-thiol compound.

[0228] The linear polymer may include a repeating unit derived from a carbon-carbon unsaturated bond (e.g., a carbon-carbon double bond), the repeating unit may include a carboxylic acid group, or the linear polymer may include an ethylene repeating unit.

[0229] The carboxylic acid group-containing repeating unit may include a unit derived from a monomer containing a carboxylic acid group and a carbon-carbon double bond, a unit derived from a monomer having a dianhydride residue, or a combination thereof.

[0230] The (polymer) matrix can include a carboxylic acid group-containing compound (eg, a binder, binder polymer, or dispersant) (eg, for dispersing or binding nanoparticles).

[0231] The first composite (or film or pattern thereof) can, for example, have a thickness of 30 μm or less, e.g., 25 μm or less, 20 μm or less, 15 μm or less, 10 μm or less, 8 μm or less, or 7 μm or less, and a thickness of more than 2 μm, e.g., 3 μm or more, 3.5 μm or more, 4 μm or more, 5 μm or more, 6 μm or more, 7 μm or more, 8 μm or more, 9 μm or more, or 10 μm or more.

[0232] The nanoparticle(s), a composite (pattern) containing the nanoparticle(s), or a color conversion panel containing the composite may be included in an electronic device. Such electronic devices may include, but are not limited to, a display device, a light-emitting diode (LED), an organic light-emitting diode (OLED), a quantum dot LED, a sensor, a solar cell, an imaging sensor, a photodetector, or a liquid crystal display device. The quantum dots may be included in an electronic apparatus. Such electronic devices may include, but are not limited to, a mobile terminal device, a monitor, a laptop, a television, a display board, a camera, an automobile, etc. The electronic device may be a mobile terminal device, a monitor, a laptop, or a television including a display device (or light-emitting element) containing quantum dots. The electronic device may be a camera or a mobile terminal device including an image sensor containing quantum dots. The electronic device may be a camera or an automobile including a photodetector containing quantum dots.

[0233] One embodiment provides a color conversion layer (e.g., a color conversion structure or color conversion panel) including a color conversion region containing the semiconductor nanoparticles. The color conversion panel includes a color conversion layer including color conversion regions and, optionally, partition walls defining each region of the color conversion layer, the color conversion region including a first region corresponding to a first pixel, the first region containing the semiconductor nanoparticles or the composite. In one embodiment of the color conversion panel, the composite may be in the form of a patterned film. In another embodiment, the composite may be in the form of a sheet.

[0234] The first region includes a first composite, the first composite including a matrix and semiconductor nanoparticles dispersed within the matrix, configured to emit a first light. One embodiment provides the semiconductor nanoparticles or population thereof.

[0235] The color conversion layer (e.g., color conversion structure) may include the composite or a patterned film thereof according to one embodiment. FIG. 3a is a schematic cross-sectional view of a color conversion panel according to one embodiment. Referring to FIG. 3a, the color conversion panel may optionally further include partitions (e.g., black matrix (BM), banks, or a combination thereof) defining each region of the color conversion layer (e.g., color conversion structure). FIG. 3b shows an electronic device (display device) including a color conversion panel and a light source according to another embodiment. In the electronic device, a color conversion panel including a color conversion layer or color conversion structure is disposed on an LED-on-chip (e.g., a micro LED-on-chip). Referring to FIG. 3b, a circuit (Si Driver IC) for driving the light source is disposed below a light source (e.g., a blue LED) configured to emit incident light (e.g., blue light). The color conversion layer may include a first composite containing semiconductor nanoparticles that emit a first light (e.g., green light), a second composite containing semiconductor nanoparticles that emit a second light (e.g., red light), or a third composite that emits or transmits a third light (e.g., incident light or blue light). A partition (e.g., based on an inorganic material such as silicon or silicon oxide, or an organic material) is disposed between each composite. The partition may include a trench hole, a via hole, or a combination thereof. A first optical element (e.g., an absorptive color filter) may be disposed on the light extraction surface of the color conversion layer. An additional optical element, such as a microlens, may be disposed on the first optical element.

[0236] The color conversion region includes a first region configured to emit the first light (or green light) (e.g., upon irradiation with incident light). In one embodiment, the first region can correspond to a green pixel. The first region includes a first composite (e.g., a light-emitting composite). The first light can have an emission peak wavelength within a wavelength range described below. The first light will be described in detail in the description of the semiconductor nanoparticles. The emission peak wavelength of the green light may be 500 nm or more, 501 nm or more, 504 nm or more, 505 nm or more, or 520 nm or more. The maximum emission peak wavelength of the green light may be 580 nm or less, 560 nm or less, 550 nm or less, 530 nm or less, 525 nm or less, 520 nm or less, 515 nm or less, or 510 nm or less.

[0237] The color conversion zone can further include (e.g., one or more) second zones configured to emit a second light (e.g., red light) different from the first light (e.g., upon irradiation with excitation light). The second zones can include a second composite. The semiconductor nanoparticle composite in the second zone can include semiconductor nanoparticles (e.g., quantum dots) that emit light of a different wavelength (e.g., a different color) than the nanoparticle composite in the first zone.

[0238] The second light may be red light having an emission peak wavelength in the range of 600 nm to 650 nm (e.g., 620 nm to 650 nm). The color conversion panel may further include one or more third regions that emit or transmit a third light (e.g., blue light) different from the first light and the second light. The incident light may include the third light (e.g., blue light) and optionally green light. The third light may include blue light having an emission peak wavelength in the range of 380 nm or more (e.g., 440 nm or more, 445 nm or more, 450 nm or more, or 455 nm or more), and 480 nm or less, 475 nm or less, 470 nm or less, 465 nm or less, or 460 nm or less.

[0239] In one embodiment, the color conversion panel or the color conversion layer includes a plurality of first regions, and the composite can be configured in a predetermined pattern so as to be disposed in each of the first regions of the color conversion panel. The composite (or these patterns) can be manufactured from an (ink) composition by any method, for example, photolithography or inkjet printing. Accordingly, one embodiment relates to a composition containing semiconductor nanoparticles, which will be described in detail herein.

[0240] In one embodiment, an electronic device or display device (e.g., a display panel) can further include a color conversion layer (or color conversion panel) and, optionally, a light source. The light source can be configured to provide incident light to the color conversion layer or the color conversion panel. In one embodiment, the display panel includes a light-emitting panel (or light source), the color conversion panel, and a light-transmitting layer located between the light-emitting panel and the color conversion panel. The color conversion panel includes a substrate, and the color conversion layer is disposed on the substrate (see Figures 4a and 4c).

[0241] The light source or light emitting panel (if present) can be configured to provide incident light to the color conversion panel or color conversion layer, and the incident light can have an emission peak wavelength in the range of 440 nm or more, e.g., 450 nm or more, and 580 nm or less, e.g., 480 nm or less, 470 nm or less, or 460 nm or less.

[0242] In one embodiment, an electronic device (e.g., a light-emitting device) can include a sheet of the nanoparticle composite. Referring to FIG. 4b, the device includes a backlight unit 410 and a liquid crystal panel 420, where the backlight unit 410 can include a quantum dot-polymer composite sheet (QD sheet). Specifically, the backlight unit 410 can have a structure in which a reflector, a light guide plate (LGP), a light source (e.g., a blue LED), a quantum dot-polymer composite sheet (QD sheet), and an optical film (e.g., a prism, a double brightness enhance film (DBEF)) are stacked. The liquid crystal panel 420 can be disposed on the backlight unit 410 and can have a structure including liquid crystals and color filters between two polarizers (Pol). The quantum dot-polymer composite sheet (QD sheet) can include quantum dots that absorb light from a light source and emit red light and quantum dots that emit green light. Blue light provided from a light source passes through the quantum dot polymer composite sheet and is converted into white light by combining with red and green light emitted from the semiconductor nanoparticles. This white light is separated into blue, green, and red light by a color filter in the LCD panel and can be emitted to the outside for each pixel. Referring to Figure 4d, the backlight unit (BLU) may be a direct-type BLU without a light guide plate and may include multiple LEDs (e.g., mini LEDs).

[0243] The color conversion panel may include a substrate, and the color conversion layer may be disposed on the substrate. The color conversion layer or the color conversion panel may include a patterned film of nanoparticle composites. The patterned film may include repeating sections configured to emit desired light. The second section may be a red light-emitting section. The first section may be a green light-emitting section. The third section may be a section that emits or transmits blue light. Details of the first, second, and third sections are the same as those described above.

[0244] The light-emitting panel or the light source may be an element that emits incident light (e.g., excitation light). The excitation light may include blue light and, optionally, green light. The light source may include an LED. The light source may include an organic LED (OLED). The light source may include a micro LED. An optical element that blocks (e.g., reflects or absorbs) blue light (and, optionally, green light), such as a blue light (and, optionally, green light) blocking layer or a first optical filter described below, may be disposed on the front surface (light-emitting surface) of the first and second areas. When the light source includes a blue-emitting organic light-emitting diode and a green-emitting organic light-emitting diode, a green light-removing filter may further be disposed on a third section through which the blue light passes.

[0245] The light-emitting panel or the light source includes a plurality of light-emitting units corresponding to the first and second regions, respectively, and the light-emitting units may include a first electrode and a second electrode facing each other, and an (organic) electroluminescent layer disposed between the first and second electrodes. The electroluminescent layer may include an organic light-emitting material. For example, each light-emitting unit of the light source may include an electroluminescent element (e.g., an organic light-emitting diode) configured to emit light of a predetermined wavelength (e.g., blue light, green light, or a combination thereof). The structures and materials of the electroluminescent elements and organic light-emitting diodes are known and are not particularly limited.

[0246] The display panel and the color conversion panel will be described in more detail below with reference to the drawings.

[0247] 4a and 4c, a display panel or electronic device 1000 according to an embodiment includes a light-emitting panel 40 or a light source and a color conversion panel 50. The display panel or electronic device may further include, but is not limited to, a light-transmitting layer 60 disposed between the light-emitting panel 40 and the color conversion panel 50, a bonding material 70 bonding the light-emitting panel 40 and the color conversion panel 50, or a combination thereof. The light-transmitting layer may include a passivation layer, a filler material, an encapsulation layer, or a combination thereof. The light-transmitting layer material may be selected appropriately and is not particularly limited. The light-transmitting layer material may include an inorganic material, an organic material, an organic-inorganic hybrid material, or a combination thereof.

[0248] The light-emitting panel 40 and the color conversion panel 50 face each other with the light-transmitting layer 60 sandwiched therebetween, and the color conversion panel 50 is disposed in the direction in which light is emitted from the light-emitting panel 40. The bonding material 70 is disposed along the edges of the light-emitting panel 40 and the color conversion panel 50, and may be, for example, a sealing material.

[0249] Referring to FIG. 5a, a display panel 1000 according to an embodiment includes a display area 1000D for displaying an image and a non-display area 1000P located around the display area 1000D and having a bonding material 400 disposed therein.

[0250] The display region 1000D includes a plurality of pixels (PX) arranged along rows (e.g., in the x direction) and / or columns (e.g., in the y direction), and each pixel (PX) includes a plurality of sub-pixels (PX1, PX2, PX3) that display different colors. Here, a configuration in which three sub-pixels (PX1, PX2, PX3) form one pixel is shown as an example, but this is not limited thereto. An additional sub-pixel, such as a white sub-pixel, may be included, or one or more sub-pixels that display the same color may be included. The pixels (PX) may be arranged, for example, in a Bayer matrix, a PenTile matrix, and / or a diamond matrix, but are not limited thereto.

[0251] Each sub-pixel (PX1, PX2, PX3) can display three primary colors or a combination of three primary colors, for example, red, green, blue, or a combination thereof. For example, the first sub-pixel (PX1) can display red, the second sub-pixel (PX2) can display green, and the third sub-pixel (PX3) can display blue.

[0252] Although the drawings illustrate an example in which all sub-pixels have the same size, the present invention is not limited thereto, and at least one of the sub-pixels may be larger or smaller than the other sub-pixels.Although the drawings illustrate an example in which all sub-pixels have the same shape, the present invention is not limited thereto, and at least one of the sub-pixels may have a shape different from the other sub-pixels.

[0253] In one embodiment of a display panel or electronic device, the light-emitting panel may include a substrate and (e.g., oxide-based) TFTs disposed on the substrate, on which light-emitting elements (which may have, for example, a tandem structure) may be disposed.

[0254] The light-emitting element may include an emitting layer (e.g., a blue emitting layer, a green emitting layer, or a combination thereof) between facing first and second electrodes. A charge generating layer may be disposed between each emitting layer. The first and second electrodes may each be patterned with a plurality of electrode elements corresponding to pixels. The first electrode may be an anode or a cathode. The second electrode may be a cathode or an anode.

[0255] The light emitting device may include an organic LED, a nanorod LED, a mini LED, a micro LED, or a combination thereof.

[0256] 5b to 5e are cross-sectional views illustrating examples of light-emitting devices. In one embodiment, the mini LED may have a size of, but is not limited to, 100 micrometers (μm) or more, 150 μm or more, 200 μm or more to 1 mm or less, 0.5 mm or less, 0.15 mm or less, or 0.12 mm or less. In one embodiment, the micro LED may have a size of less than 100 μm, 50 μm or less, or 10 μm or less. The size of the micro LED may be, but is not limited to, 0.1 μm or more, 0.5 μm or more, 1 μm or more, or 5 μm or more.

[0257] Referring to FIG. 5b, in one embodiment, the light-emitting element 180 may include a first electrode 181 and a second electrode 182 facing each other; an emitting layer 183 located between the first electrode 181 and the second electrode 182; and, optionally, auxiliary layers 184 and 185 located between the first electrode 181 and the emitting layer 183 and between the second electrode 182 and the emitting layer 183.

[0258] The first electrode 181 and the second electrode 182 are disposed to face each other along the thickness direction (e.g., the z direction), and one of the first electrode 181 and the second electrode 182 may be an anode and the other may be a cathode. The first electrode 181 may be a translucent electrode (or transparent electrode), a semi-transparent electrode (or semi-transparent electrode), or a reflective electrode, and the second electrode 182 may be a translucent electrode or a semi-translucent electrode. The transparent or semi-transparent electrode can be made of a conductive oxide such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), tin oxide (SnO), aluminum tin oxide (AlTO), and fluorine-doped tin oxide (FTO), or a thin single-layer or multi-layer metal thin film including silver (Ag), copper (Cu), aluminum (Al), magnesium (Mg), magnesium-silver (Mg-Ag), magnesium-aluminum (Mg-Al), or a combination thereof. The reflective electrode can include a metal, a metal nitride, or a combination thereof, such as, but not limited to, silver (Ag), copper (Cu), aluminum (Al), gold (Au), titanium (Ti), chromium (Cr), nickel (Ni), alloys thereof, nitrides thereof (e.g., TiN), or a combination thereof.

[0259] The light-emitting layer(s) 183 may emit a first light emitter that emits light having a blue emission spectrum, a second light emitter that emits light having a green emission spectrum, or a combination thereof.

[0260] The maximum emission wavelength of the blue emission spectrum can be in a wavelength range of about 400 nm or more and less than 500 nm, and within this range, can be in a wavelength range of about 410 nm to 490 nm, about 420 nm to 480 nm, 430 nm to 470 nm, 440 nm to 465 nm, 445 nm to 460 nm, 450 nm to 458 nm, or a combination thereof.

[0261] The maximum emission wavelength of the green emission spectrum can be in a wavelength range of about 500 nm or more and less than 590 nm, and within this range, can be in a wavelength range of about 510 nm to 580 nm, about 515 nm to 570 nm, 520 nm to 560 nm, 525 nm to 555 nm, 530 nm to 550 nm, 535 nm to 545 nm, or a combination thereof.

[0262] For example, the light-emitting layer(s) 183 or the light-emitting material contained therein may include a phosphorescent material, a fluorescent material, or a combination thereof. For example, the light-emitting material may include an organic light-emitting material, which may be a low-molecular-weight compound, a high-molecular-weight compound, or a combination thereof. The specific types of the phosphorescent material and the fluorescent material are not particularly limited and may be appropriately selected from known materials. For example, the light-emitting material may include an inorganic light-emitting material, which may be an inorganic semiconductor, a quantum dot, a perovskite, or a combination thereof. The inorganic semiconductor may include a metal nitride, a metal oxide, or a combination thereof. The metal nitride, the metal oxide, or a combination thereof may include a Group III metal such as aluminum, gallium, indium, or thallium, a Group IV metal such as silicon, germanium, or tin, or a combination thereof. When the light-emitting material includes an inorganic light-emitting material, the light-emitting element 180 may be a quantum dot light-emitting diode, a perovskite light-emitting diode, or a micro light-emitting diode (μLED). Materials usable as the inorganic light-emitting material are well known.

[0263] In one embodiment, the light-emitting device 180 may further include auxiliary layers 184 and 185. The auxiliary layers 184 and 185 may be located between the first electrode 181 and the light-emitting layer 183, and between the second electrode 182 and the light-emitting layer 183, respectively. The auxiliary layers 184 and 185 may each be a charge auxiliary layer for controlling charge injection and / or mobility. The auxiliary layers 184 and 185 may each be one or more layers, such as a hole injection layer, a hole transport layer, an electron blocking layer, an electron injection layer, an electron transport layer, a hole blocking layer, or a combination thereof. At least one of the auxiliary layers 184 and 185 may be omitted. Materials for each auxiliary layer may be appropriately selected from known materials for organic electroluminescent devices, etc.

[0264] The light-emitting elements 180 arranged in each sub-pixel (PX1, PX2, PX3) may be the same or different from each other. The light-emitting elements 180 arranged in each sub-pixel (PX1, PX2, PX3) may emit light of the same or different emission spectrums. For example, the light-emitting elements 180 arranged in each sub-pixel (PX1, PX2, PX3) may emit light of a blue emission spectrum, light of a green emission spectrum, or a combination thereof. The light-emitting elements 180 arranged in each sub-pixel (PX1, PX2, PX3) may be separated by a pixel defining film (not shown).

[0265] Referring to FIG. 5c, the light-emitting element 180 may be a tandem-structured light-emitting element, and may include a first electrode 181 and a second electrode 182 facing each other; a first light-emitting layer 183a and a second light-emitting layer 183b located between the first electrode 181 and the second electrode 182; a charge generation layer 186 located between the first light-emitting layer 183a and the second light-emitting layer 183bk; and, optionally, auxiliary layers 184 and 185 located between the first electrode 181 and the first light-emitting layer 183a and between the second electrode 182 and the second light-emitting layer 183b.

[0266] The first electrode 181, the second electrode 182, and the auxiliary layers 184 and 185 are the same as those described above.

[0267] The first light-emitting layer 183a and the second light-emitting layer 183b can emit light with the same or different emission spectrums. In one embodiment, the first light-emitting layer 183a or the second light-emitting layer 183b can emit light with a blue emission spectrum or a green emission spectrum. The charge generation layer 186 can inject charges into the first light-emitting layer 183a and / or the second light-emitting layer 183b and adjust the charge balance between the first light-emitting layer 183a and the second light-emitting layer 183b. The charge generation layer 186 can include, for example, an n-type layer and a p-type layer, and can include, for example, an electron transport material and / or a hole transport material containing an n-type dopant and / or a p-type dopant. The charge generation layer 186 can be one layer or two or more layers.

[0268] Referring to Figure 5d, the light-emitting element (e.g., having a tandem structure) may include a first electrode 181 and a second electrode 182 facing each other; a first light-emitting layer 183a, a second light-emitting layer 183b, and a third light-emitting layer 183c located between the first electrode 181 and the second electrode 182; a first charge generation layer 186a located between the first light-emitting layer 183a and the second light-emitting layer 183b; a second charge generation layer 186b located between the second light-emitting layer 183b and the third light-emitting layer 183c; and optionally auxiliary layers 184 and 185 located between the first electrode 181 and the first light-emitting layer 183a and between the second electrode 182 and the third light-emitting layer 183c.

[0269] The first electrode 181, the second electrode 182 and the auxiliary layers 184 and 185 are the same as those described above.

[0270] The first light-emitting layer 183a, the second light-emitting layer 183b, and the third light-emitting layer 183c can emit light of the same or different emission spectrums. The first light-emitting layer 183a, the second light-emitting layer 183b, and the third light-emitting layer 183c can emit blue light. In one embodiment, the first light-emitting layer 183a and the third light-emitting layer 183c can emit light of a blue emission spectrum, and the second light-emitting layer 183b can emit light of a green emission spectrum. In another embodiment, the first light-emitting layer 183a and the third light-emitting layer 183c can emit light of a green emission spectrum, and the second light-emitting layer 183b can emit light of a blue emission spectrum.

[0271] The first charge generation layer 186a can inject charges into the first light-emitting layer 183a and / or the second light-emitting layer 183b, and can adjust the charge balance between the first light-emitting layer 183a and the second light-emitting layer 183b. The second charge generation layer 186b can inject charges into the second light-emitting layer 183b and / or the third light-emitting layer 183c, and can adjust the charge balance between the second light-emitting layer 183b and the third light-emitting layer 183c. Each of the first and second charge generation layers 186a and 186b may be one layer or two or more layers.

[0272] Referring to FIG. 5 e , a light emitting device 180 includes a first electrode 181 , a second electrode 182 , and a light emitting layer 183 including a plurality of nanostructures 187 .

[0273] One of the first electrode 181 and the second electrode 182 may be an anode, and the other may be a cathode. The first electrode 181 and the second electrode 182 may be electrodes patterned according to the double-row direction of the plurality of nanostructures 187, and may include, but are not limited to, conductive oxides such as indium tin oxide (ITO), indium zinc oxide (IZO), zinc oxide (ZnO), tin oxide (SnO), aluminum tin oxide (AlTO), and fluorine-doped tin oxide (FTO); silver (Ag), copper (Cu), aluminum (Al), gold (Au), titanium (Ti), chromium (Cr), nickel (Ni), alloys thereof, nitrides thereof (e.g., TiN); or combinations thereof.

[0274] The light-emitting layer 183 may include a plurality of nanostructures 187, and each of the sub-pixels (PX1, PX2, PX3) may include a plurality of nanostructures 187. The plurality of nanostructures 187 may be arranged in one direction, but is not limited to this. The nanostructures 187 are compound semiconductors that emit light of a predetermined wavelength when a current is applied, and may be linear nanostructures such as nanorods or nanoneedles. The diameter or major axis of nanostructure 187 may be, for example, a few nanometers to a few hundred nanometers, and the aspect ratio of nanostructure 187 may be greater than about 1, greater than about 1.5, greater than about 2.0, greater than about 3.0, greater than about 4.0, greater than about 4.5, greater than about 5.0, greater than about 1 and less than or equal to 20, between about 1.5 and 20, between about 2.0 and 20, between about 3.0 and 20, between about 4.0 and 20, between about 4.5 and 20, or between about 5.0 and 20, or any combination thereof.

[0275] Each nanostructure 187 may include a p-type region 187p, an n-type region 187n, and a multiple quantum well region 187i, and may emit light from the multiple quantum well region 187i. The nanostructures 187 may include, for example, gallium nitride (GaN), indium gallium nitride (InGaN), aluminum gallium nitride (AlGaN), or a combination thereof, and may have, for example, a core-shell structure.

[0276] The nanostructures 187 may emit light having the same or different emission spectrums. In one embodiment, the first nanostructure 187a may emit light having a blue emission spectrum, for example, a maximum emission wavelength in a wavelength range of about 400 nm to less than 500 nm, about 410 nm to 490 nm, or about 420 nm to 480 nm.

[0277] FIG. 6 is a schematic cross-sectional view of an element (or display panel) according to one embodiment. Referring to FIG. 6, the light source (or light-emitting panel) may include an organic light-emitting diode (OLED) that emits blue light (and optionally green light). The OLED may include two or more pixel electrodes formed on a substrate, a pixel defining film formed between adjacent pixel electrodes, an organic light-emitting layer formed on each pixel electrode, and a common electrode layer formed on the organic light-emitting layer. A thin-film transistor and a substrate may be disposed below the OLED. The pixel regions of the OLED may be disposed corresponding to the first, second, and third regions described below. While FIG. 6 illustrates a configuration in which the color conversion panel and the OLED panel are separated, the color conversion panel may be stacked directly above the OLED panel.

[0278] A laminated structure including a pattern of semiconductor nanoparticle composites (e.g., a first region including red semiconductor nanoparticles (quantum dots) and a second region including green semiconductor nanoparticles (quantum dots)) and a substrate is disposed on the light source. Blue light emitted from the light source is incident on the first region and the second region, which emit red and green light, respectively. The blue light emitted from the light source can pass through the third region. Optionally, an element that blocks excitation light (a first optical filter or excitation light blocking layer) may be disposed between the semiconductor nanoparticle composite layer (R, G) and the substrate. When the excitation light includes blue light and green light, a green light blocking filter is added to the third region. The first optical filter or excitation light blocking layer will be described in more detail below.

[0279] Such devices can be fabricated by separately fabricating the color conversion panel and an LED or OLED (e.g., emitting blue light and optionally green light) and then combining them, or by directly forming a pattern of semiconductor nanoparticle composites on the LED or OLED.

[0280] In one embodiment of the color conversion panel or display device, the substrate may be a substrate containing an insulating material. The substrate may include, but is not limited to, glass; various polymers such as polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polycarbonate, polyacrylate, etc.; polysiloxane (e.g., PDMS); inorganic materials such as Al2O3 and ZnO; or combinations thereof. The thickness of the substrate may be appropriately selected taking into account the substrate material, etc., and is not particularly limited. The substrate may be flexible. The substrate may be configured to have a transmittance of 50% or more, 60% or more, 70% or more, 80% or more, or 90% or more for light emitted from the semiconductor nanoparticles.

[0281] A wiring layer including thin film transistors is formed on the substrate. The wiring layer may further include gate lines, storage voltage lines, gate insulating films, data lines, source electrodes, drain electrodes, semiconductor layers, and passivation films. The detailed structure of the wiring layer varies depending on the embodiment. The gate lines and storage voltage lines are electrically isolated from each other, and the data lines cross the gate lines and storage voltage lines in an insulated manner. The gate electrodes, source electrodes, and drain electrodes respectively constitute the control terminals, input terminals, and output terminals of the thin film transistors. The drain electrodes are electrically connected to pixel electrodes, which will be described later.

[0282] The pixel electrode can function as an electrode (e.g., an anode) of the display device. The pixel electrode can be formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The pixel electrode can also be formed of a light-shielding material such as gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), or titanium (Ti). The pixel electrode can also have a two-layer structure in which the transparent conductive material and the light-shielding material are sequentially stacked.

[0283] A pixel defining layer (PDL) may be formed between two adjacent pixel electrodes, overlapping the ends of the pixel electrodes and dividing the pixel electrodes into pixel units. The pixel defining layer is an insulating layer, and can electrically isolate the two or more pixel electrodes.

[0284] The pixel definition layer may cover only a portion of the upper surface of the pixel electrode, and the remaining portion of the pixel electrode not covered by the pixel definition layer may form an opening. An organic light-emitting layer (described later) may be formed on the limited area of ​​the opening.

[0285] The organic light-emitting layer is defined as each pixel region by the pixel electrode and the pixel defining layer. That is, a region in which one organic light-emitting unit layer is formed and in contact with one pixel electrode separated by the pixel defining layer can be defined as one pixel region. In the display device according to one embodiment, the organic light-emitting layer is defined as a first pixel region, a second pixel region, and a third pixel region, and each pixel region is spaced apart by the pixel defining layer at a predetermined interval.

[0286] The organic light-emitting layer may emit a third light in the visible light range or the UV range. Each of the first to third pixel regions of the organic light-emitting layer may emit the third light. In one embodiment, the third light may include light in the visible light range with high energy, such as blue light (and optionally green light). When all pixel regions of the organic light-emitting layer are designed to emit the same light, the pixel regions of the organic light-emitting layer may be formed of the same or similar materials or may exhibit the same or similar physical properties. This significantly reduces the difficulty of forming the organic light-emitting layer, and such a display device may be easily adapted to larger / larger display device processes. However, the organic light-emitting layer according to one embodiment is not necessarily limited thereto, and the organic light-emitting layer may be configured to emit two or more different types of light.

[0287] The organic light-emitting layer includes an organic light-emitting unit layer for each pixel region, and each organic light-emitting unit layer may further include additional layers (e.g., a hole injection layer, a hole transport layer, an electron transport layer, etc.) in addition to the light-emitting layer.

[0288] The common electrode can function as the cathode of the display device. The common electrode can be formed of a transparent conductive material such as indium tin oxide (ITO) or indium zinc oxide (IZO). The common electrode can be integrally formed on the organic light-emitting layer.

[0289] A planarization or passivation layer (not shown) may be formed on the common electrode, and the planarization layer may comprise an insulating material (e.g., transparent) to ensure electrical isolation from the common electrode.

[0290] In one embodiment, the display device may further include a lower substrate, a polarizer disposed below the lower substrate, and a liquid crystal layer interposed between the laminated structure and the lower substrate, and the laminated structure may be disposed such that the light-emitting layer faces the liquid crystal layer. The display device may further include a polarizer between the liquid crystal layer and the light-emitting layer. The light source may further include an LED and, optionally, a light guide plate.

[0291] A display device (e.g., a liquid crystal display device) according to a non-limiting embodiment will be described with reference to the drawings. Fig. 7a is a schematic cross-sectional view of a liquid crystal display device according to a non-limiting embodiment. Referring to Fig. 7a, the display device according to the embodiment includes a liquid crystal panel 200, a polarizer 300 disposed below the liquid crystal panel 200, and a backlight unit disposed below the polarizer 300.

[0292] The liquid crystal panel 200 includes a lower substrate 210, a laminated structure, and a liquid crystal layer 220 interposed between the laminated structure and the lower substrate. The laminated structure may include a transparent substrate 240, a first optical filter layer, a light-emitting layer 230 including a quantum dot-polymer composite pattern, and a second optical filter layer 311.

[0293] The lower substrate 210, also called an array substrate, may be a transparent insulating material substrate. The contents of the substrate are the same as those described above. A wiring board 211 is provided on the upper surface of the lower substrate 210. The wiring board 211 may include, but is not limited to, a plurality of gate lines (not shown) and data lines (not shown) that define pixel regions, thin film transistors provided adjacent to intersections of the gate lines and data lines, and pixel electrodes for each pixel region. The specific contents of such a wiring board are well known and are not particularly limited.

[0294] A liquid crystal layer 220 is provided on the wiring board 211. The liquid crystal layer 220 may include alignment films 221 above and below the liquid crystal layer 220 for initial alignment of the liquid crystal material contained therein. Specific details of the liquid crystal material and the alignment films (e.g., liquid crystal material, alignment film material, liquid crystal layer formation method, liquid crystal layer thickness, etc.) are well known and are not particularly limited.

[0295] A lower polarizer 300 is provided below the lower substrate. The material and structure of the polarizer 300 are well known and are not particularly limited. A backlight unit (e.g., emitting blue light) is provided below the polarizer 300. An upper optical element or polarizer 300 is provided between the liquid crystal layer 220 and the transparent substrate 240, but is not limited thereto. For example, the upper polarizer is disposed between the liquid crystal layer 220 and the light-emitting layer 230. The polarizer may be any polarizer that can be used in a liquid crystal display device. The polarizer may be, but is not limited to, triacetyl cellulose (TAC) having a thickness of 200 μm or less. In another embodiment, the upper optical element may be a refractive index-adjusting coating without a polarization function.

[0296] The backlight unit includes a light source 110. The light source can emit blue light or white light. The light source can include, but is not limited to, a blue LED, a white LED, a white OLED, or a combination thereof.

[0297] The backlight unit may further include a light guide plate 120. In one embodiment, the backlight unit may be an edge-type backlight unit. For example, the backlight unit may include, but is not limited to, a reflector (not shown), a light guide plate (not shown) disposed on the reflector to provide a surface light source to the liquid crystal panel 200, and / or one or more optical sheets (not shown) disposed on the light guide plate, such as a diffuser plate or a prism sheet. The backlight unit may not include a light guide plate. In one embodiment, the backlight unit may be a direct lighting type backlight unit. For example, the backlight unit may include a reflector (not shown) and a plurality of fluorescent lamps arranged at regular intervals above the reflector, or may include an LED driving board on which a plurality of light emitting diodes (LEDs) are arranged, and a diffuser plate and optionally one or more optical sheets thereon. Details of such backlight units (e.g., details of each component, such as the light emitting diodes, fluorescent lamps, light guide plate, various optical sheets, and reflector) are well known and are not particularly limited.

[0298] A black matrix 241 having openings is provided on the bottom surface of the transparent substrate 240, covering gate lines, data lines, thin film transistors, and the like of the wiring board provided on the lower substrate. For example, the black matrix 241 may have a lattice shape. A light-emitting layer 230 having a nanoparticle-polymer composite pattern including a first region (R) emitting a first light (e.g., red light), a second region (G) emitting a second light (e.g., green light), and a third region (B) emitting / transmitting, for example, blue light is provided in the openings of the black matrix 241. If necessary, the light-emitting layer may further include one or more fourth regions. The fourth region may include quantum dots emitting light of a color (e.g., cyan, magenta, or yellow) different from the light emitted from the first to third regions.

[0299] The patterned sections of the light-emitting layer 230 may be repeated corresponding to pixel regions formed on the lower substrate. A transparent common electrode 231 may be provided on the self-emissive color filter layer.

[0300] The third region (B) that transmits / emits blue light may be a transparent color filter that does not change the emission spectrum of the light source. In this case, blue light emitted from the backlight unit may be polarized and enter the polarizer and the liquid crystal layer, and then be emitted as is. Optionally, the third region may contain quantum dots that emit blue light.

[0301] As described above, the display device or light-emitting element of an embodiment may further include an excitation light-blocking layer or a first optical filter layer (hereinafter referred to as the first optical filter layer) if necessary. The first optical filter layer may be disposed between the bottom surfaces of the first region (R) and the second region (G) and a substrate (e.g., an upper substrate or transparent substrate 240) or on the upper surface of the substrate. The first optical filter layer may be a sheet having an opening in a portion corresponding to a pixel region (third region) that displays blue, or may be formed in portions corresponding to the first and second regions. That is, the first optical filter layer may be integrally formed in the remaining portions except for the portion overlapping the third region, as shown in FIGS. 3a, 3b, 6, and 7a, but is not limited thereto. Two or more first optical filter layers may be spaced apart from each other in the first and second regions and, optionally, in positions overlapping the third region. If the light source includes a green light-emitting element, a green light-blocking layer may be disposed on the third region.

[0302] The first optical filter layer can, for example, block light in a certain wavelength range within the visible light range and transmit light in the remaining wavelength range, for example, block blue light (or green light) and transmit light excluding blue light (or green light). The first optical filter layer can, for example, transmit green light, red light, and / or yellow light, which is a mixture of these colors. The first optical filter layer can transmit blue light and block green light, and may be disposed on blue light-emitting pixels.

[0303] The first optical filter layer can substantially block the excitation light and transmit light in a desired wavelength range, and the transmittance of the first optical filter layer for light in the desired wavelength range may be about 70% or more, 80% or more, 90% or more, or even 100%.

[0304] A first optical filter layer that selectively transmits red light can be disposed at a position overlapping the red light emitting section, and a first optical filter layer that selectively transmits green light can be disposed at a position overlapping the green light emitting section. The first optical filter layer can include at least one of a first filter region that blocks (e.g., absorbs) blue light and red light and selectively transmits light in a predetermined range (e.g., about 500 nm or more, about 510 nm or more, or about 515 nm or more, and about 550 nm or less, about 545 nm or less, about 540 nm or less, about 535 nm or less, about 530 nm or less, about 525 nm or less, or about 520 nm or less), and a second filter region that blocks (e.g., absorbs) blue light and green light and selectively transmits light in a predetermined range (e.g., about 600 nm or more, about 610 nm or more, or about 615 nm or more, and about 650 nm or less, about 645 nm or less, about 640 nm or less, about 635 nm or less, about 630 nm or less, about 625 nm or less, or about 620 nm or less). When the light source emits a mixture of blue and green light, the first optical filter layer can further include a third filter region that selectively transmits blue light and blocks green light.

[0305] The first filter region may be positioned to overlap the green light-emitting section, the second filter region may be positioned to overlap the red light-emitting section, and the third filter region may be positioned to overlap the blue light-emitting section.

[0306] The first filter region, the second filter region, and optionally the third filter region may be optically isolated. Such a first optical filter layer can contribute to improving the color purity of the display element.

[0307] The display element may further include a second optical filter layer (e.g., a red / green or yellow light recycling layer) disposed between the light-emitting layer and the liquid crystal layer (e.g., between the light-emitting layer and the upper polarizer) that transmits at least a portion of the third light (excitation light) and reflects at least a portion of the first light and / or the second light. The first light may be red light, the second light may be green light, and the third light may be blue light. The second optical filter layer may transmit only the third light (B) in the blue light wavelength range having a wavelength range of 500 nm or less, and may reflect light in the wavelength range above 500 nm, such as green light (G), yellow light, and red light (R), that cannot pass through the second optical filter layer. The reflected green light and red light may pass through the first and second regions and be emitted to the outside of the display device.

[0308] The second optical filter layer or the first optical filter layer can be formed as a unitary layer having a relatively flat surface.

[0309] The first optical filter layer can include a polymer thin film containing a dye and / or pigment that absorbs light of the wavelength to be blocked. The second optical filter layer and the first optical filter layer can include a single layer having a low refractive index, for example, a transparent thin film having a refractive index of 1.4 or less, 1.3 or less, or 1.2 or less. The second optical filter layer or the first optical filter layer having a low refractive index can be, for example, a porous silicon oxide, a porous organic material, a porous organic / inorganic composite, or a combination thereof.

[0310] The first or second optical filter layer may include multiple layers with different refractive indices. It may be formed by alternately stacking two layers with different refractive indices. For example, the first or second optical filter layer may be formed by alternately stacking a material with a high refractive index and a material with a low refractive index.

[0311] In one embodiment, the electronic device may include a light-emitting element (e.g., an electroluminescent element) including the nanoparticles. Figure 7b is a schematic cross-sectional view of one embodiment of the light-emitting element (electroluminescent element). Referring to Figure 7b, the light-emitting element may include an anode 1 and a cathode 5 facing each other; a quantum dot light-emitting layer 3 located between the anode and the cathode and including a plurality of quantum dots; and a hole auxiliary layer 2 disposed between the anode and the quantum dot light-emitting layer. The hole auxiliary layer may further include a hole injection layer (HIL), a hole transport layer (HTL), an electron blocking layer (EBL), or a combination thereof. The hole auxiliary layer may include any organic or inorganic material having hole properties. The quantum dot light-emitting element may further include an electron auxiliary layer 4 between the cathode and the quantum dot light-emitting layer. The electron auxiliary layer may further include an electron injecting layer (EIL), an electron transporting layer (ETL), a hole blocking layer (HBL), or a combination thereof. The electron auxiliary layer may include any organic or inorganic material having electronic properties.

[0312] Specific examples are presented below. However, the following examples are merely for the purpose of specifically illustrating and explaining the invention, and should not be construed as limiting the scope of the invention. [Example]

[0313] Analysis method

[0314] [1] Photoluminescence analysis Photoluminescence (PL) spectra of the prepared nanoparticles and the composites containing them were obtained using a Hitachi F-7000 spectrophotometer at an excitation wavelength of 450 nm.

[0315] [2] Blue light absorption rate, quantum yield (QY) The amount of incident light (B) with a wavelength of 450 nm was measured using the integrating sphere or integrating hemisphere of an absolute quantum efficiency measurement device (QE-2100, Otsuka). The QD-polymer composite was then placed in the integrating sphere or integrating hemisphere, and the incident light was irradiated to measure the total amount of primary light (A) emitted from the composite and the amount of incident light (B') that passed through the composite. The incident light absorbance was calculated from the measured values ​​using the following formula: Incident light absorption rate (%) = [(B-B') / B] x 100 External quantum efficiency (EQE, %) = [A / B] × 100 Internal quantum efficiency (IQE, %) = [A / (B-B')] × 100

[0316] [3] Process maintenance rate analysis The semiconductor nanoparticle-polymer composite obtained by polymerization was heat-treated at 180° C. for 30 minutes, and the process retention rate was measured by the following formula. Process maintenance rate (%)=[IQE2 / IQE1]×100 In the above formula, IQE1 is the internal quantum efficiency of the semiconductor nanoparticle-polymer composite before heat treatment after polymerization, and IQE2 is the internal quantum efficiency of the semiconductor nanoparticle-polymer composite after heat treatment.

[0317] [4]ICP-AES analysis Inductively coupled plasma atomic emission spectroscopy (ICP-AES) was performed using a Shimadzu ICPS-8100.

[0318] Example 1: [1] Formation of the first semiconductor nanocrystal (or core) Sulfur was dispersed in oleylamine to prepare a 1M sulfur precursor-containing solution (hereinafter referred to as the sulfur precursor). Octadecene (ODE), oleylamine, silver acetate, indium acetate, and gallium acetylacetonate were placed in a 100 mL reaction flask and vacuum treated at room temperature for 10 minutes. The gas in the flask was then replaced with nitrogen, and the sulfur precursor and todecanethiol were added. The flask temperature was then raised to the reaction temperature (210 °C) and allowed to react for up to 60 minutes. The flask temperature was then lowered to 180 °C, trioctylphosphine (TOP) was added, and the mixture was cooled to room temperature. A non-solvent (ethanol) was added to the resulting mixture to promote precipitation. The resulting first semiconductor nanocrystals (hereinafter also referred to as cores) were collected by centrifugation and redispersed in toluene.

[0319] The molar ratio of silver precursor, indium precursor, gallium precursor, and sulfur precursor used was 0.8:about 1:1:4.

[0320] [2] Formation, separation and washing of intermediate particles Gallium bromide was dissolved in trioctylphosphine to prepare a 1 M gallium precursor solution (hereinafter referred to as the first gallium precursor). A silver compound (silver acetate 0.06 M) was dispersed in oleylamine to prepare a silver compound dispersion.

[0321] Dimethylthiourea (DMTU), oleylamine, and octadecene were placed in a flask as the first sulfur precursor and vacuum-treated at 120°C for 10 minutes. After replacing the atmosphere in the reaction flask with N2, the flask was heated to 240°C (first injection temperature), and the first gallium precursor, first semiconductor nanocrystal, and silver compound dispersion were added. The reactor was then heated to 260°C (first reaction temperature) and reacted for 180 minutes (first reaction time). The temperature of the reaction solution was lowered to 180°C, trioctylphosphine was added, and the mixture was cooled to room temperature. A non-solvent (ethanol) was added to the reaction solution at room temperature to promote precipitation of the resulting intermediate particles. The resulting intermediate particles were collected by centrifugation and dispersed in toluene. Precipitation and separation (centrifugation) were repeated using ethanol as a washing solvent.

[0322] The silver compound was used at approximately 4 mol % relative to the gallium precursor, and the molar ratio of the first gallium precursor to the first sulfur precursor used was 0.72:1 (gallium precursor:sulfur precursor).

[0323] [3] Preparation of semiconductor nanoparticles: Gallium bromide and gallium chloride were dissolved in trioctylphosphine solution to prepare a 1 M solution (hereinafter referred to as the second gallium precursor). A silver compound (silver acetate 0.06 M) was dispersed in oleylamine to prepare a silver compound dispersion.

[0324] Dimethylthiourea (DMTU), oleylamine, and octadecene were added to the flask as the second sulfur precursor and then vacuum treated at 120°C for 10 minutes. After replacing the atmosphere in the reaction flask with N2, the flask was heated to 240°C (second injection temperature), and the second gallium precursor, intermediate particles, and silver compound dispersion were added. The reactor was then heated to 260°C (second reaction temperature) and reacted for 200 minutes. The temperature of the reaction solution was lowered to 180°C, trioctylphosphine was added, and the mixture was then cooled to room temperature. A non-solvent (ethanol) was added to the reaction solution at room temperature to promote precipitation of the resulting semiconductor nanoparticles. The resulting semiconductor nanoparticles were collected by centrifugation and dispersed in toluene.

[0325] The silver compound was used in an amount of approximately 5 mol % relative to the second gallium precursor, in which the content of gallium chloride per mole of gallium bromide was approximately 0.3 moles.

[0326] The molar ratio of the second gallium precursor to the second sulfur precursor used was 0.75:1 (second gallium precursor:second sulfur precursor). The content of the second gallium precursor was approximately 0.81 moles per mole of the first gallium precursor. The content of the gallium precursor used in the subsequent process per mole of indium precursor added to the core synthesis was approximately 388 moles.

[0327] The produced semiconductor nanoparticles were subjected to ICP-AES analysis and photoluminescence analysis, and the results are summarized in Table 1 (element molar ratio and charge balance value) and Table 2 (photoluminescence properties), as well as Figures 8a and 8b, respectively.

[0328] Example 2: Semiconductor nanoparticles were prepared in the same manner as in Example 1, except that the molar ratio of the first gallium precursor to the first sulfur precursor was changed to 0.77:1, the content of the silver compound relative to the gallium precursor in the synthesis of intermediate particles was 2.8 mol%, the content of the second gallium precursor was approximately 0.94 mol per mol of the first gallium precursor, and the content of the gallium precursor used in the subsequent process per mol of indium precursor added to the core synthesis was approximately 317 mol. ICP-AES analysis and photoluminescence analysis were performed on the prepared semiconductor nanoparticles, and the results are summarized in Table 1 (element molar ratios and charge balance values) and Table 2 (photoluminescence properties) as well as Figures 8a and 8b.

[0329] Example 3: Semiconductor nanoparticles were prepared in the same manner as in Example 1, except that the molar ratio of the first gallium precursor to the first sulfur precursor used in the synthesis of intermediate particles was changed to 0.77:1, the molar ratio of the second gallium precursor to the second sulfur precursor was changed to 1.125:1, the content of the silver compound in the synthesis of intermediate particles was 5.5 mol% relative to the gallium precursor, the content of the second gallium precursor was 1.46 mol per mol of the first gallium precursor, and the content of the gallium precursor used in the subsequent process per mol of indium precursor added to the core synthesis was approximately 553 mol. ICP-AES analysis and photoluminescence analysis were performed on the prepared semiconductor nanoparticles, and the results are summarized in Table 1 (element molar ratios and charge balance values) and Table 2 (photoluminescence properties) as well as Figures 8a and 8b.

[0330] Example 4: Semiconductor nanoparticles were prepared in the same manner as in Example 1, except that the molar ratio of the first gallium precursor to the first sulfur precursor in the synthesis of intermediate particles was changed to 0.71:1, the content of the silver compound relative to the gallium precursor in the synthesis of intermediate particles was 5.7 mol%, the content of the second gallium precursor was about 0.76 mol per mol of the first gallium precursor, and the content of the gallium precursor used in the subsequent process per mol of indium precursor added to the synthesis of cores was about 589 mol. ICP-AES analysis and photoluminescence analysis were performed on the prepared semiconductor nanoparticles, and the results are summarized in Table 1 (element molar ratios and charge balance values) and Table 2 (photoluminescence properties) as well as Figures 8a and 8b.

[0331] Example 5: Semiconductor nanoparticles were prepared in the same manner as in Example 1, except that the molar ratio of the first gallium precursor to the first sulfur precursor in the synthesis of intermediate particles was changed to approximately 0.9:1, the content of the silver compound relative to the gallium precursor in the synthesis of intermediate particles was 3.5 mol%, the content of the second gallium precursor was approximately 0.91 mol per mol of the first gallium precursor, and the content of the gallium precursor used in the subsequent process per mol of indium precursor added to the synthesis of cores was approximately 415 mol. ICP-AES analysis and photoluminescence analysis were performed on the prepared semiconductor nanoparticles, and the results are summarized in Table 1 (element molar ratios and charge balance values) and Table 2 (photoluminescence properties) as well as Figures 8a and 8b.

[0332] Comparative Example 1: [1] A core was obtained in the same manner as in Example 1, except that the molar ratio of the silver precursor, indium precursor, gallium precursor, and sulfur precursor used was adjusted to 0.8:0.9:1.25:4.

[0333] [2] Gallium bromide was dissolved in trioctylphosphine solution to prepare a 1 M gallium precursor solution (hereafter referred to as gallium precursor). A silver compound (silver acetate 0.06 M) was dispersed in oleylamine to prepare a silver compound dispersion.

[0334] Dimethylthiourea (DMTU), oleylamine, and octadecene were placed in a flask as a sulfur precursor and vacuum treated at 120°C for 10 minutes. After replacing the atmosphere in the reaction flask with N2, the flask was heated to 240°C (first injection temperature), and the gallium precursor, first semiconductor nanocrystal, and silver compound dispersion were added. The reactor was then heated to 260°C (first reaction temperature) and reacted for 180 minutes (first reaction time). The temperature of the reaction solution was lowered to 180°C, trioctylphosphine was added, and the mixture was cooled to room temperature. A non-solvent (ethanol) was added to the reaction solution at room temperature to promote precipitation of the formed semiconductor nanoparticles. The semiconductor nanoparticles were collected by centrifugation and dispersed in toluene.

[0335] The molar ratio of the gallium precursor to the sulfur precursor used was 1.125:1 (gallium precursor:sulfur precursor). The silver compound was used at 9.2 mol% relative to the gallium precursor. The amount of gallium precursor used in subsequent processes was approximately 715 mol per mol of indium precursor added to the core synthesis. ICP-AES analysis and photoluminescence analysis were performed on the produced semiconductor nanoparticles, and the results are summarized in Table 1 (element molar ratio and charge balance value) and Table 2 (photoluminescence properties) as well as Figures 8a and 8b.

[0336] Comparative Example 2: Semiconductor nanoparticles were prepared in the same manner as in Comparative Example 1, except that the amount of gallium precursor used in the subsequent process per mole of indium precursor added to the core synthesis was increased to 931 moles.

[0337] The produced semiconductor nanoparticles were subjected to ICP-AES analysis and photoluminescence analysis, and the results are summarized in Table 1 (element molar ratio and charge balance value) and Table 2 (photoluminescence properties) and Figures 8a and 8b.

[0338] Comparative Example 3: Semiconductor nanoparticles were prepared in the same manner as in Comparative Example 1, except that the silver compound was used in an amount of about 14 mol % relative to the gallium precursor.

[0339] The produced semiconductor nanoparticles were subjected to ICP-AES analysis and photoluminescence analysis, and the results are summarized in Table 1 (element molar ratio and charge balance value) and Table 2 (photoluminescence properties) and Figures 8a and 8b.

[0340] Comparative Example 4: Semiconductor nanoparticles were prepared in the same manner as in Comparative Example 1, except that the molar ratio of the gallium precursor to the sulfur precursor used was 0.9:1 (gallium precursor:sulfur precursor), the silver compound was used at 4.6 mol% relative to the gallium precursor, and the content of the gallium precursor used in the subsequent process per mole of indium precursor added to the core synthesis was increased to 1,429 moles.

[0341] The produced semiconductor nanoparticles were subjected to ICP-AES analysis and photoluminescence analysis, and the results are summarized in Table 1 (element molar ratio and charge balance value) and Table 2 (photoluminescence properties), as well as Figures 8a and 8b.

[0342] [Table 1] [Table 2]

[0343] The results in Tables 1 and 2 confirm that the semiconductor nanoparticles of the examples exhibit improved luminescence properties (high quantum yield and narrow half-width) even though they have a Ga / In ratio of 20 or more. The results in Figures 8a and 8b confirm that the semiconductor nanoparticles of the examples exhibit significantly reduced traps compared to the semiconductor nanoparticles of the comparative examples.

[0344] Experimental Example 1 [1] Preparation of the composite The toluene solutions of the semiconductor nanoparticles obtained in Examples 1, 2, 4, and 5 and Comparative Examples 1 to 4 were mixed with a binder (a quaternary copolymer of methacrylic acid, benzyl methacrylate, hydroxyethyl methacrylate, and styrene, acid value: 130 mg KOH / g, molecular weight: 8000) solution (PGMEA concentration: 30 wt%) to prepare nanoparticle-binder dispersions.

[0345] The nanoparticle binder dispersion was mixed with hexaacrylate having the following structure as a photopolymerizable monomer, an oxime ester compound as an initiator, TiO nanoparticles as metal oxide fine particles, and PGMEA to prepare a composition: [ka] [ka] The composition produced contains 20 wt % semiconductor nanoparticles based on the total solids weight.

[0346] The composition was spin-coated onto a glass substrate at 600 rpm for 5 seconds to obtain a film. The resulting film was pre-baked (PRB) at 100°C for 2 minutes. The pre-baked film was then irradiated with light (wavelength: 395 nm, intensity: 4 J) and heat-treated (POB) at 180°C for 30 minutes to obtain a composite (thickness: approximately 7 μm).

[0347] It was confirmed that all of the composites containing semiconductor nanoparticles in the examples exhibited an incident light absorptance of 90% or more.

[0348] The photoconversion efficiency (internal quantum efficiency) of the composites containing semiconductor nanoparticles of the examples and comparative examples was measured, and the internal quantum efficiency after POB, the tail (trap emission) percentage after PRB, and the tail (trap emission) percentage after POB were calculated, respectively. Some of the results are shown in Table 3 below.

[0349] [Table 3]

[0350] Relative internal quantum efficiency after POB (%): [internal quantum efficiency of the complex / internal quantum efficiency of the complex of Comparative Example 1] × 100

[0351] The relative internal quantum efficiency after POB of the composite containing the semiconductor nanoparticles of Example 2 was 141.18%, and the trap emission percentage of the composite after POB was 17.3%.

[0352] From the results in Table 3 and others, it was confirmed that the semiconductor nanoparticles of the examples can exhibit improved luminescence efficiency in the composite and can maintain a relatively suppressed trap luminescence percentage even after heat treatment (in other words, can exhibit improved stability).

[0353] The process retention rates were measured for the composites containing the semiconductor nanoparticles of Examples 1, 4, and 5, respectively, and the results are summarized in Table 4.

[0354] [Table 4]

[0355] From the results in Table 4, it was confirmed that the composite containing semiconductor nanoparticles of the examples can exhibit an increased process maintenance rate.

[0356] Experimental Example 2 An ink composition was prepared by mixing the semiconductor nanoparticles obtained in Examples 1, 3, 4, and 5, hexanediol diacrylate (monomer, Cas No. 13048-33-4, purchased from Sigma-Aldrich), titanium oxide particles, and an initiator. The semiconductor nanoparticles, titanium oxide particles, and initiator contents in the composition were 20 wt%, 5 wt%, and 1 wt%, respectively, based on the total weight of the composition, with the remainder being monomer. The prepared composition was deposited on a substrate and exposed (exposure dose 4 Joules, wavelength 395 nm) to photopolymerize the composition and obtain a 7 μm-thick film. The prepared film was post-baked at 100°C for 30 minutes.

[0357] The internal quantum efficiency after POB, the tail (trap emission) percentage after PRB, and the tail (trap emission) percentage after POB of the prepared composite were calculated, and some of the results are shown in Table 5 below.

[0358] [Table 5]

[0359] From the results in Table 5, it can be seen that the semiconductor nanoparticles of the examples can exhibit relatively high levels of internal quantum efficiency and process maintenance rate, and can maintain a relatively low trap emission percentage of the composite after exposure or POB.

[0360] Although the embodiments have been described in detail above, the scope of the invention is not limited to these examples, and various modifications and improvements made by those skilled in the art using the basic concepts defined in the claims below also fall within the scope of the invention. [Explanation of symbols]

[0361] 1 anode 2. Hole auxiliary layer 3. Quantum dot light-emitting layer 4 Electronic auxiliary layer 5 cathode 40 Light-emitting panel 50 Color Conversion Panel 60 Translucent layer 70 Binding material 110 Light source 120 Light guide plate 180 Light-emitting element 181 1st electrode 182 2nd electrode 183 Light-emitting layer 184 Auxiliary layer 185 Auxiliary layer 186 Charge generation layer 187 Nanostructures 200 LCD panels 210 Lower board 211 Wiring board 220 Liquid Crystal Layer 221 Orientation Film 230 Light-emitting layer 231 Transparent common electrode 240 Transparent substrate 241 Black Matrix

Claims

1. Semiconductor nanoparticles, the semiconductor nanoparticles comprise silver, indium, gallium, and sulfur; the semiconductor nanoparticles have a molar ratio of gallium to indium (Ga / In) of 20 or more and 40 or less; The semiconductor nanoparticles have a quantum yield of 70% or more and 100% or less.

2. 2. The semiconductor nanoparticles according to claim 1, wherein the molar ratio of gallium to indium (Ga / In) in the semiconductor nanoparticles is 23 or more and 37 or less.

3. the molar ratio of silver to indium (Ag / In) in the semiconductor nanoparticles is 10 or more and 16 or less, or The sum of indium and gallium relative to sulfur ((In + Ga / S)) is 0.3 or more and 0.66 or less, or 2. The semiconductor nanoparticles according to claim 1, wherein the molar ratio of silver to indium (Aa / In) is 10 or more and 16 or less, and the sum of indium and gallium to sulfur ((In+Ga / S)) is 0.3 or more and 0.66 or less.

4. 2. The semiconductor nanoparticles according to claim 1, wherein the molar ratio of indium to the sum of indium and gallium (In / (In+Ga)) in the semiconductor nanoparticles is 0.024 or more and less than 0.

05.

5. In the semiconductor nanoparticles, the molar ratio of indium to sulfur (In / S) is greater than or equal to 0.01 and less than or equal to 0.045; or 2. The semiconductor nanoparticles according to claim 1, wherein the molar ratio of gallium to sulfur (Ga / S) is 0.45 or more and 0.78 or less.

6. In the semiconductor nanoparticles, 2. The semiconductor nanoparticles according to claim 1, wherein the molar ratio of the sum of indium and gallium to silver [(In+Ga) / Ag)] is 1.3 or more and 2.2 or less.

7. 10. The semiconductor nanoparticles of claim 1, wherein the semiconductor nanoparticles comprise first semiconductor nanocrystals comprising silver, indium, gallium, and sulfur, and second semiconductor nanocrystals comprising silver, gallium, and sulfur.

8. The semiconductor nanoparticles according to claim 1 , wherein the semiconductor nanoparticles have a quantum yield of 75% or more and 99% or less.

9. the semiconductor nanoparticles are configured to emit a first light; the first light has an emission peak wavelength of 500 nm or more and 560 nm or less; The semiconductor nanoparticles according to claim 1 , wherein the emission spectrum of the first light has a half-width of 5 nm or more and 50 nm or less.

10. The semiconductor nanoparticles according to claim 1, wherein the semiconductor nanoparticles have a trap emission percentage calculated by the following formula of 20% or less: Trap emission percentage = [trap emission area of ​​emission spectrum / total area of ​​emission spectrum] × 100 In the above formula, the trap emission area refers to the area of ​​the emission spectrum at a given emission peak wavelength + 50 nm or more.

11. A method for producing semiconductor nanoparticles, comprising: the semiconductor nanoparticles comprise silver, indium, gallium, and sulfur; the semiconductor nanoparticles have a molar ratio of gallium to indium (Ga / In) of 20 or more and 40 or less; The method includes combining, in a first medium comprising a first organic solvent, first semiconductor nanocrystals comprising silver, a Group 13 element, and a chalcogen element, a first sulfur precursor, a first gallium precursor, and optionally a first silver compound; heating the first medium at a first reaction temperature to form intermediate particles; separating the formed intermediate particles from the first medium; combining the separated intermediate particles, a second sulfur precursor, a second gallium precursor, and optionally a second silver compound in a second medium comprising a second organic solvent; and The method includes heating the second medium at a second reaction temperature to form semiconductor nanoparticles.

12. the first gallium precursor comprises gallium bromide and gallium chloride; 12. The method of claim 11, wherein the second gallium precursor comprises gallium bromide, gallium chloride, or a combination thereof.

13. further comprising washing the intermediate particles with a post-separation wash solvent; The method of claim 11, wherein the washing solvent comprises a C1 to C10 alcohol.

14. When a first silver compound is present in the first medium, the content of the first silver compound is 0.1 mol % or more and 50 mol % or less relative to the first gallium precursor; 12. The method of claim 11, wherein when a second silver compound is present in the second medium, the content of the second silver compound is 0.1 mol % or more and 50 mol % or less relative to the second gallium precursor.

15. A method for producing a semiconductor nanoparticle-based liquid dispersion comprising the semiconductor nanoparticles of claim 1 and a liquid vehicle, The ink composition, wherein the liquid vehicle comprises a polymerizable monomer, an organic solvent, or a combination thereof.

16. A semiconductor nanoparticle composite comprising a matrix and semiconductor nanoparticles dispersed within the matrix, The semiconductor nanoparticle composite, wherein the semiconductor nanoparticles comprise the semiconductor nanoparticles according to claim 1 .

17. The semiconductor nanoparticle composite according to claim 16, wherein the semiconductor nanoparticle composite has a trap emission percentage calculated by the following formula of 20% or less: Trap emission percentage = [trap emission area of ​​emission spectrum / total area of ​​emission spectrum] × 100 In the above formula, the trap emission area refers to the area of ​​the emission spectrum at a given emission peak wavelength + 50 nm or more.

18. A display device comprising the semiconductor nanoparticles according to claim 1.

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