JP2017110039A - Illuminant and production method of the same, fluorescent probe using illuminant, fluorescent probe dispersion liquid, led device, color wheel for projection display device, wavelength conversion film, display device and photo-electric conversion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an illuminant comprising semiconductor nanoparticles having a high fluorescent quantum yield and little variation in the particle size and emitting fluorescent light with high color purity, a production method of the illuminant, and others.SOLUTION: The illuminant comprises semiconductor nanoparticles made of a compound represented by general formula (1) M1M2X(in general formula (1), M1 represents at least one element selected from the group consisting of Li, Na, K, Rb and Cs; M2 represents one of or both of Ge and Sn elements; X represents at least one element selected from the group consisting of F, Cl, Br and I; m1 represents a value ranging from 0.7 to 1.3; m2 represents a value ranging from 0.7 to 1.3; and x represents a value ranging from 2.0 to 4.0). The number-basis percentage of semiconductor nanoparticles having an aspect ratio of 1.0 to 1.8 with respect to the whole semiconductor nanoparticles included in the illuminant is specified to 50% or more; and a coefficient of variance of a major diameter α of the semiconductor nanoparticles is specified to 40% or less.SELECTED DRAWING: None

Description

  The present invention relates to a luminescent material, a method for manufacturing the same, a fluorescent probe using the luminescent material, a fluorescent probe dispersion, an LED device, a color wheel for a projection display device, a wavelength conversion film, a display device, and a photoelectric conversion device.

  Conventionally, it is known that a fluorescent material excited by light of a specific wavelength is used for a wavelength conversion layer of various illumination devices, a labeled probe for fluorescently labeling a specific biological substance, and the like. One such fluorescent material is semiconductor nanoparticles.

  In general, semiconductor nanoparticles have an advantage that they are excellent in light resistance and that the fluorescence intensity is hardly lowered even when irradiated with excitation light for a long time. Among such semiconductor particles, cadmium selenide is known as a material having a particularly high fluorescence quantum yield. However, cadmium is preferably used in a small amount from the viewpoint of influence on the living body and consideration of the environment. Therefore, it has been desired to provide semiconductor nanoparticles that use a small amount of cadmium and exhibit a high quantum yield.

  In response to such demands, ternary semiconductor nanoparticles have been proposed that have an emission peak wavelength in a wavelength range of 700 nm or more and that do not contain cadmium (Patent Document 1). The semiconductor nanoparticles of Patent Document 1 can be obtained by obtaining a bulk light-emitting material and then converting it into nanoparticles using a ball mill or the like.

Special table 2009-530488

  The semiconductor nanoparticles described in Patent Document 1 have a perovskite crystal structure, and the closer the aspect ratio is to 1.4, that is, the cubic crystal structure, the smaller the band gap, the desired It is assumed that light of a wavelength (for example, visible light) is easily obtained. At the same time, it is expected that the fluorescence quantum yield is increased. However, the semiconductor nanoparticles obtained by the method described in Patent Document 1 have many lattice defects generated during pulverization, and the fluorescence quantum yield tends to be low. Furthermore, the semiconductor nanoparticles obtained by the method described in Patent Document 1 have a problem in that since the variation in particle size is large, the half-value width of the emission peak tends to be widened and the color purity of the fluorescence is low. Accordingly, there has been a demand for ternary semiconductor nanoparticles having high fluorescence quantum yield and sharp half-value width of emission peak.

  The present invention has been made in view of the above problems. That is, the present invention uses a phosphor including semiconductor nanoparticles having a high fluorescence quantum yield, a small variation in particle size, and a high color purity of emitted fluorescence, a method for producing the phosphor, and various phosphors using the phosphor. An object of the present invention is to provide a fluorescent probe, an LED device, a wavelength conversion film, and a photoelectric conversion device.

That is, the first of the present invention is the following light emitter.
[1] General formula (1) M1 _m1 M2 _m2 X _x (In general formula (1), M1 represents one or more elements selected from the group consisting of Li, Na, K, Rb, and Cs; , Ge and Sn, or both elements, X represents one or more elements selected from the group consisting of F, Cl, Br, and I, and m1 is 0.7 to 1 .3, m2 represents a value in the range of 0.7 to 1.3, and x represents a value in the range of 2.0 to 4.0. An illuminant comprising a plurality of nanoparticles, wherein the aspect ratio (α / β) relative to the total number of the semiconductor nanoparticles contained in the illuminant is 1 when the major axis of the semiconductor nanoparticles is α and the minor axis is β. The ratio of the number of the semiconductor nanoparticles being 0 to 1.8 is 50% or more, and the semiconductor nanoparticles The variation coefficient of the major axis α of the child is 40% or less, the light emitter.

[2] The ratio of the number of the semiconductor nanoparticles having the aspect ratio of 1.0 to 1.8 to the total number of the semiconductor nanoparticles included in the luminous body is 70% or more. Luminous body.
[3] The ratio of the number of the semiconductor nanoparticles having the aspect ratio of 1.0 to 1.5 to the total number of the semiconductor nanoparticles included in the light emitter is 70% or more. [1] or [2 ] The light-emitting body of description.

[4] The luminous body according to any one of [1] to [3], wherein a variation coefficient of the major axis α of the semiconductor nanoparticles is 20% or less.
[5] The luminous body according to any one of [1] to [4], wherein the semiconductor nanoparticles have an emission peak wavelength in a wavelength range of 400 to 800 nm.
[6] The light emitting body according to any one of [1] to [5], wherein the semiconductor nanoparticles have an emission peak wavelength in a wavelength range of 400 to 700 nm.

[7] The light emitter according to any one of [1] to [6], wherein a half-value width of a light emission peak of the semiconductor nanoparticles is 60 nm or less.
[8] The light emitter according to any one of [1] to [7], wherein the semiconductor nanoparticles are covered with a shell layer.
[9] The light emitter according to any one of [1] to [8], wherein a ratio of a lattice constant of the shell layer to a lattice constant of the semiconductor nanoparticles is 70% to 130%.

The second of the present invention lies in the following method for producing a light emitter.
[10] The method for manufacturing a light emitter according to any one of [1] to [9], wherein a heating step of heating a solution containing a plurality of metal compounds and a solvent, and a cooling step of cooling the solution, The manufacturing method of the light-emitting body containing these.
[11] The heating step is a step of heating the solution to 120 ° C. or higher, and the cooling step is a step of cooling the solution with a temperature gradient of 1 ° C./second or higher. A method for manufacturing a luminous body.
[12] The method for producing a light emitter according to any one of [1] to [9], wherein a solution containing a plurality of metal compounds and a solvent is filled in pores of a porous template, A method for manufacturing a luminous body, comprising: a step of heating; and a cooling step of cooling the solution.

The third aspect of the present invention resides in various uses and manufacturing methods using the above-described light emitter.
[13] A fluorescent probe comprising the illuminant according to any one of [1] to [9] and a target-directing ligand bound to the illuminant.
[14] The targeting ligand is an antibody or an affinity substance thereof, a cell membrane affinity substance, a viral cell recognition site, a lipophilic tracer, a virus particle having no replication function, an organelle affinity substance, folic acid, transferrin, transferrin The fluorescent probe according to [13], which is one or more molecules selected from the group consisting of a binding peptide and a protein having a binding property to a sugar chain.
[15] The fluorescent probe according to [13] or [14], wherein a functional group on the surface of the light emitter and a functional group of the target-directing ligand are covalently bonded.
[16] A fluorescent probe dispersion liquid in which the fluorescent probe according to any one of [13] to [15] is dispersed in water or a buffer solution.

[17] The light emitting device according to any one of [1] to [9], including an LED element and a wavelength conversion layer disposed on a light emission surface of the LED element. Including LED device.
[18] The LED device according to [17], wherein the wavelength conversion layer includes a wavelength conversion film including the light emitter and a binder.
[19] A color wheel for a projection display device provided with a light adjustment layer disposed around a rotation center, wherein the light adjustment layer comprises the light emitter according to any one of [1] to [9]. Including a color wheel for a projection display device.

[20] A wavelength conversion film comprising the light emitter according to any one of [1] to [9] and a binder.
[21] A display device comprising the wavelength conversion film according to [20].
[22] A photoelectric conversion device comprising the wavelength conversion film according to [20].

  The phosphor of the present invention has a high fluorescence quantum yield and a high color purity of emitted fluorescence. Therefore, the light emitter of the present invention can be applied to various uses such as a fluorescent probe and a material for a wavelength conversion layer of an illumination device.

FIG. 1 is a schematic diagram for explaining a crystal structure of a perovskite crystal structure. FIG. 2 is an image diagram of a fluorescent probe to which a light emitter according to an embodiment of the present invention is applied. FIG. 3A and FIG. 3B are schematic cross-sectional views of an embodiment of an LED device in which a light emitter is applied to a wavelength conversion layer. FIG. 4A is a schematic diagram for explaining a configuration of a projection display device, and FIG. 4B is an embodiment of a color wheel for a projection display device in which a light emitter is applied to a light adjustment layer. It is a front view of a form. 5A to 5D are schematic cross-sectional views of an embodiment of a backlight device in which a light emitter is applied to a wavelength conversion layer. FIG. 6 is a schematic cross-sectional view of one embodiment of a photoelectric conversion device in which a light emitter is applied to a wavelength conversion layer.

  Hereinafter, although embodiment of this invention is described in detail, this invention is not limited to the following embodiment, In the range of the summary, it can implement in various changes. In addition, in this application, "-" showing a numerical range is used by the meaning containing the numerical value described before and behind that as a lower limit and an upper limit.

1. Light Emitter The light emitter according to one embodiment of the present invention is represented by the general formula (1) M1 _m1 M2 _m2 X _x (wherein M1 is selected from the group consisting of Li, Na, K, Rb, and Cs. M2 represents one or both of Ge and Sn, and X represents one or more elements selected from the group consisting of F, Cl, Br, and I. M1 represents a value in the range of 0.7 to 1.3, m2 represents a value in the range of 0.7 to 1.3, and x represents a value in the range of 2.0 to 4.0. A plurality of semiconductor nanoparticles composed of a ternary compound having a perovskite crystal structure. When M1, M2, and X are each composed of a plurality of elements, m1, m2, and x represent total values of equivalents of these elements.

  The semiconductor nanoparticles having a perovskite crystal structure can have a cubic, tetragonal or orthorhombic crystal structure as shown in the schematic diagram of FIG. And when the crystal structure of the semiconductor nanoparticles has these crystal structures, the yield of the fluorescent particles of the semiconductor nanoparticles tends to increase, and particularly when the crystal structure is cubic, the yield of the fluorescent particles of the semiconductor nanoparticles is very high. Become. The crystal structure of the semiconductor nanoparticles can be determined by the aspect ratio (α / β) when the major axis of the semiconductor nanoparticles is α and the minor axis is β, and α / β is 1.0 to 1.8. If it is within the range, it can be said to have these crystal structures.

  In contrast, the ternary semiconductor nanoparticles having a perovskite structure obtained by the method described in Patent Document 1 have a large aspect ratio, and it is difficult to sufficiently increase the fluorescence quantum yield. These semiconductor nanoparticles are produced by pulverizing a bulk light emitting material with a ball mill or the like. Even if a bulk light-emitting material having a cubic or tetragonal crystal structure can be produced, it is difficult to grind to obtain a desired aspect ratio, and the resulting semiconductor nanoparticles have an aspect ratio of It was easy to grow. Furthermore, lattice defects are likely to occur in the crystal during pulverization, and from this point, the fluorescence quantum yield tends to be low. In addition, conventionally known semiconductor nanoparticles often have non-uniform particle sizes, and the emission peak wavelength of the fluorescence emitted by each semiconductor nanoparticle is likely to vary.

  On the other hand, in the luminous body of this embodiment, the number ratio of the semiconductor nanoparticles having an aspect ratio of 1.0 to 1.8 is 50% or more. In other words, since the phosphor includes many semiconductor nanoparticles having a crystal structure of any one of cubic, tetragonal, and orthorhombic, the fluorescence quantum yield of the phosphor is very high. In addition, since the variation coefficient (CV value) of the major axis of the particles is sufficiently small, variations in the color (wavelength) of the fluorescence emitted by each phosphor nanoparticle hardly occur, and the color purity of the fluorescence emitted by the phosphor is high.

  Here, the luminous body of the present embodiment may be an aggregate of semiconductor nanoparticles, but may be an aggregate of core-shell type particles in which the semiconductor nanoparticles are covered with a shell layer. When the semiconductor nanoparticles are covered with the shell layer, the quantum confinement effect of the semiconductor nanoparticles is increased, and the fluorescence quantum yield is easily increased. Hereinafter, each of the semiconductor nanoparticles and the shell layer will be described.

(1) Semiconductor nanoparticle The semiconductor nanoparticle contained in the light emitter of the present embodiment is composed of a compound represented by the general formula (1) M1 _m1 M2 _m2 X _x . In the general formula (1), M1 represents one or more elements selected from the group consisting of Li, Na, K, Rb, and Cs. Among these, Rb or Cs is preferable from the viewpoint that fluorescence in the visible light range can be obtained. The compound constituting the semiconductor nanoparticles may contain only one of the above elements as M1, or two or more of them.

  M2 represents Ge or Sn, and the compound constituting the semiconductor nanoparticles may include only one of them or both of them. X represents one or more elements selected from the group consisting of F, Cl, Br, and I. Among these, Cl, Br, and I are preferable from the viewpoint of obtaining fluorescence in the visible light region. In the compound constituting the semiconductor nanoparticles, only one of the above elements may be contained as X, or two or more of them may be contained.

  Moreover, m1 shows the content rate of the element represented by M1, and is a value of the range of 0.7-1.3, Preferably it is 0.9-1.1, More preferably, it is 0.95- 1.05. M2 represents the content ratio of the element represented by M2, and is a value in the range of 0.7 to 1.3, preferably 0.9 to 1.1, more preferably 0.95. 1.05. Moreover, x shows the content rate of the element represented by X, and is the value of the range of 2.0-4.0, Preferably it is 2.7-3.3, More preferably, it is 2.9-3 .1.

  In the present embodiment, the ratio of “the number of semiconductor nanoparticles having an aspect ratio (α / β) of 1.0 to 1.8” to “the total number of semiconductor nanoparticles included in the light emitter” is 50% or more. . The ratio of “the number of semiconductor nanoparticles having an aspect ratio (α / β) of 1.0 to 1.8” to “the total number of semiconductor nanoparticles included in the light emitter” is preferably 70% or more. The ratio of the “number of semiconductor nanoparticles having an aspect ratio (α / β) of 1.0 to 1.5” to the “total number of semiconductor nanoparticles included in the light emitter” is particularly 70% or more. preferable. A large ratio of “number of semiconductor nanoparticles having an aspect ratio (α / β) of 1.0 to 1.5” means that a large percentage of semiconductor nanoparticles have a cubic crystal structure. When the proportion of semiconductor nanoparticles having a cubic crystal structure is increased in the illuminant, the fluorescence quantum yield of the illuminant becomes very high.

  The aspect ratio (α / β) can be measured as follows, but the measurement method is not limited to this method. First, a dispersion liquid in which semiconductor nanoparticles are dispersed in a dispersion medium is prepared, and the dispersion liquid is dropped on a slide glass and dried. Thereby, a semiconductor nanoparticle can be fixed so that a Z-axis direction may become a short axis. Subsequently, image observation is performed from the X-axis / Y-axis plane of the semiconductor nanoparticles by TEM to determine the major axis α of the semiconductor nanoparticles. Then, the minor axis β is obtained by observing the sample using an AFM (atomic force microscope). Then, from these values, the major axis / minor axis (α / β) is calculated and used as the aspect ratio. In addition, the aspect ratio was calculated for 100 or more semiconductor nanoparticles included in the luminescent material, and from these data, the “ratio of semiconductor nanoparticles having an aspect ratio of 1.0 to 1.8” and “aspect ratio of 1. The ratio of semiconductor nanoparticles that is 0 to 1.5 is calculated.

  Further, when a shell layer is formed on the surface of the semiconductor nanoparticles, the aspect ratio (α / β) of the semiconductor nanoparticles can be measured as follows. First, core-shell type particles are immersed in an acid such as hydrochloric acid to gradually dissolve the shell layer. The dissolution is performed while analyzing the solution by ICP-MS (inductively coupled plasma mass spectrometry) or the like. Then, when the core (semiconductor nanoparticle) component is detected from the solution, dissolution is stopped and the aspect ratio is calculated in the same manner as described above.

In the present embodiment, the semiconductor nanoparticles have a coefficient of variation of the major axis α (hereinafter also referred to as “CV value”) of 40% or less, and more preferably 20% or less. The CV value is a numerical value representing variation in semi-statistics, and is represented by the following formula.
CV value [%] = (σ / D) × 100
In the above formula, σ represents a standard deviation, and D represents an average value of the major axis α of the semiconductor nanoparticles. The major axis α of the semiconductor nanoparticles is a value obtained by observing 100 or more particles of the semiconductor nanoparticles with a transmission electron microscope (TEM), and the standard deviation and the average particle diameter are obtained from the measured values. In addition, when the shell layer is formed on the surface of the semiconductor nanoparticle, the shell layer is dissolved by the same method as described above, and the measurement is performed after only the semiconductor particle is formed. Here, the smaller the CV value, the higher the uniformity of the major axis α of the semiconductor nanoparticles. Therefore, when the CV value is 40% or less, the uniformity of the major axis α of the semiconductor nanoparticles is increased, and variations in the intensity and chromaticity of the fluorescence emitted from each semiconductor nanoparticle are reduced.

  In addition, since the average particle diameter of the semiconductor nanoparticles correlates with the fluorescence color (emission color) emitted from the semiconductor nanoparticles, it is appropriately selected according to the desired emission color. 20 nm is preferable, and 1 to 15 nm is more preferable. When the average value of the major axis α of the semiconductor nanoparticles is within the above range, a sufficient quantum confinement effect is obtained, and the fluorescence quantum yield of each semiconductor nanoparticle is increased. In addition, when the average value of the major axis α of the semiconductor nanoparticles is increased, fluorescence having a long wavelength is easily obtained, and when the average value of the major axis α of the semiconductor nanoparticles is decreased, fluorescence having a short wavelength is easily obtained.

  The semiconductor nanoparticles preferably have an emission peak wavelength in the wavelength range of 400 to 800 nm, and more preferably have an emission peak wavelength in the wavelength range of 400 to 700 nm. When the emission peak wavelength of the semiconductor nanoparticles is 400 to 800 nm, the fluorescence emitted from the semiconductor nanoparticles can be visually recognized, so that the applications of the light emitters are diversified.

  At this time, the half-value width of the emission peak of the semiconductor nanoparticles is preferably 60 nm or less, and more preferably 50 nm or less. When the half-value width of the emission peak is 60 nm or less, the color purity of the fluorescence obtained from the light emitter is likely to be sufficiently increased. In addition, when the illuminant is used for a fluorescent probe, for example, the signal / noise ratio can be increased, so that highly accurate measurement is possible. The emission peak wavelength and the half width are measured with a fluorometer.

(2) Shell layer As described above, a shell layer covering the semiconductor nanoparticles may be formed on the surface of the semiconductor nanoparticles. The shell layer is a layer made of a material having a higher band gap energy than the semiconductor nanoparticles. When the shell layer is formed on the surface of the semiconductor nanoparticles, non-luminous energy transfer is difficult to occur between the semiconductor nanoparticles. That is, the quantum confinement effect of the semiconductor nanoparticles is increased, and the fluorescence quantum yield is easily increased.

  Here, the metal or compound constituting the shell layer is not particularly limited as long as it is a metal or compound having higher band gap energy than the semiconductor nanoparticles. Examples of metals and compounds constituting the shell layer include ZnS, ZnSe, ZnTe, CdS, CdSe, Cd, Te, HgS, HgSe, HgTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, GaSe. InN, InP, InAs, InSb, TlN, TlP, TlAs, TlSb, PbS, PbSe, PbTe, Fe, Pt, Ni, Co, Al, Ag, Au, Cu, FePt, Pd, Si, Ge and alloys thereof Etc. are included. The shell layer may contain only one kind or two or more kinds. Among these, by using a shell layer constituting material that does not contain Cd, Hg, and Pb, it is possible to obtain a light-emitting body that is suitable for applications with high safety standards.

  Here, the ratio of the lattice constant b of the shell layer to the lattice constant a of the semiconductor nanoparticles ((b / a) × 100) is preferably 70 to 130%, and preferably 80 to 120%. . The closer these lattice constants are, the easier it is to increase the fluorescence quantum yield of the light emitter. In the present specification, the “lattice constant of the semiconductor nanoparticles” means the value of the a-axis lattice constant of the crystal structure of the compound constituting the semiconductor nanoparticles, and the “lattice constant of the shell layer” The value of the a-axis lattice constant of the crystal structure of the metal or compound constituting the layer. These can be determined by XRD (X-ray diffraction).

  Further, the thickness of the shell layer is not particularly limited, but it is preferably 1 to 20 ML (unit crystal lattice layer), more preferably 1 to 10 ML (unit crystal lattice layer). If the thickness of the shell layer is equal to or greater than 1 ML and not greater than 20 ML, misfit transition is unlikely to occur and defects are unlikely to occur, so that the quantum yield and half width are unlikely to decrease.

2. Manufacturing method of luminous body The luminous body of the said embodiment can be manufactured with the following method.

(Process for producing semiconductor nanoparticles)
The above-mentioned semiconductor nanoparticles can be obtained by performing a heating step for heating a solution containing a plurality of metal compounds and a solvent and a cooling step for cooling the solution. For example, it can be obtained by preparing particles having a desired composition by a hot soap method and rapidly cooling the particles. Hereinafter, although an example of the preparation method of such a semiconductor nanoparticle is shown, the manufacturing method of the above-mentioned semiconductor nanoparticle is not limited to the said method.

First, “a metal compound A or a complex thereof containing M1 in the above general formula (1)” and “a metal compound B or a complex thereof containing M2 and X in the above general formula (1)” in a high-temperature solvent. React (heating step). When the metal compound A, the metal compound B, or a complex thereof is added to a high-temperature solvent, M1, M2, and X are temporarily dissociated and are represented by the above general formula (1) M1 _m1 M2 _m2 X _x. Nuclei of the same composition are formed. When the reaction is continued at a high temperature, M1, M2, and X are deposited on the nucleus and a crystal grows. In addition, since the surfactant is adsorbed on the crystal surface, the crystals grow without agglomeration, and the resulting semiconductor nanoparticles tend to have a uniform particle size.

  The heating temperature and heating time in the heating step are appropriately selected according to the type of metal compound A and metal compound B, the desired particle size of the semiconductor nanoparticles, and the like. Usually, the heating temperature is preferably 120 to 320 ° C, and preferably 200 to 300 ° C. When the heating temperature is 200 ° C. or higher, the crystal structure of the obtained semiconductor nanoparticles tends to be cubic. In addition, when the heating temperature is excessively high, decomposition of the solvent and the complex-forming agent may occur. However, when the heating temperature is 300 ° C. or lower, the reaction can be stably performed. Moreover, heating time can be normally 10 second-1 hour, and it is more preferable that it is 1 to 30 minutes. When the reaction time is less than 10 seconds, the reaction between the metal compound complexes does not proceed, and when the reaction time is longer than 1 hour, the particle size becomes too large to obtain the quantum confinement effect.

  The metal compound A is not particularly limited as long as it includes M1 in the general formula (1) and M1 can be dissociated in the heating step. Examples of the metal compound A include carbonates and stearates of M1. Among these, a carbonate of M1 is preferable from the viewpoint that M1 is easily dissociated in a high-temperature solvent. On the other hand, the metal compound B includes M2 and X, and is not particularly limited as long as M2 and X are dissociable in the heating step. The metal compound B may be a compound composed only of M2 and X, that is, a halide of M2, or a compound further containing an organic group in addition to M2 and X. Among these, a halide of M2 is preferable from the viewpoint that M2 and X are easily dissociated in a high-temperature solvent.

Further, the complex-forming agent that forms a complex with the metal compound A or the metal compound B is a compound that can form a complex with the metal compound A or the metal compound B that is stable at low temperatures and thermally dissociable at high temperatures. There is no particular limitation. Examples of such complex forming agents include organic compounds having a highly polar functional group. Specifically, an alkane or alkene having 6 to 22 carbon atoms having a COOH group, PO ₃ H ₂ group, PO group, SOOH group, or NH ₂ group at the terminal is included. Specific examples thereof include oleic acid, stearic acid, palmitic acid, hexylphosphonic acid, n-octylphosphonic acid, tetradecylphosphonic acid, octadecylphosphonic acid, trioctylphosphine, trioctylphosphine oxide, n-octylamine, hexadecyl Examples include amines and oleylamines.

  In addition, the solvent used in the heating step is not particularly limited as long as it is an organic solvent having a boiling point higher than the heating temperature and having a high affinity with the complex forming agent and the like. For example, the complex forming agent may be used as an organic solvent. Also, ester solvents such as methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, pentyl acetate; γ-butyrolactone, N-methyl-2-pyrrolidone, acetone, dimethyl ketone, diisobutyl ketone Ketone solvents such as cyclopentanone, cyclohexanone, methylcyclohexanone; diethyl ether, methyl-tert-butyl ether, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane, Ether solvents such as tetrahydrofuran, methyltetrahydrofuran, anisole, phenetole; methanol, ethanol, 1-propanol, 2-propanol, 1-butanol 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol, diacetone alcohol, cyclohexanol, 2-fluoroethanol, 2,2,2-trifluoroethanol, 2,2, Alcohol solvents such as 3,3-tetrafluoro-1-propanol; glycol ethers (cellosolve) such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, triethylene glycol dimethyl ether Amide solvents such as N, N-dimethylformamide, acetamide, N, N-dimethylacetamide; acetonitrile, isobutyronitrile, propionitrile, Acetonitrile solvents such as methoxyacetonitrile; carbonate solvents such as ethylene carbonate and propylene carbonate; halogenated hydrocarbon solvents such as methylene chloride, dichloromethane and chloroform; n-pentane, cyclohexane, n-hexane, benzene, toluene, xylene, etc. Hydrocarbon solvents such as: alkene solvents such as nonene, decene, and octadecene; various organic solvents such as dimethyl sulfoxide may be used. Trioctylphosphine, trioctylphosphine oxide, and oleylamine can also be used.

  The surfactant used in the heating step is not particularly limited as long as it can be adsorbed on the crystal surface even at a high temperature and can suppress aggregation between crystals. For example, the complex forming agent described above can be used as a surfactant.

After the heating step, a step (cooling step) for cooling the solution (reaction solution) is performed. At this time, the ratio of the semiconductor nanoparticles having an aspect ratio of 1.0 to 1.8 can be increased by rapidly cooling the solution as described above. As used herein, “rapid cooling” refers to cooling the solution from the temperature in the heating step to 50 ° C. or less with a temperature gradient of 1 ° C./second or more. As described above, the crystal structure of the semiconductor nanoparticles is preferably cubic. However, in general, the crystal structure of semiconductor nanoparticles is likely to undergo phase transition. For example, CsSnI ₃ undergoes phase transition to an orthorhombic crystal at 160 ° C. even if it is a cubic crystal at the time of synthesis. Moreover, even if CsSnBr ₃ is a cubic crystal at the time of synthesis, it undergoes a phase transition to an orthorhombic crystal at 20 ° C. On the other hand, when rapidly cooling from the heating temperature in the heating step to 50 ° C. or lower, the cubic structure is easily maintained even at room temperature or lower, and the semiconductor nanoparticles having an aspect ratio of 1.0 to 1.8 The ratio can be increased. The temperature gradient is more preferably 1 ° C./second or more, and further preferably 1.5 ° C./second or more.

  The quenching method in the cooling step is not particularly limited, and for example, a method of adding ice water to the reaction solution can be used. However, when the production amount of semiconductor nanoparticles is large, it is difficult to rapidly cool the reaction solution at the center of the reaction vessel. Therefore, in such a case, it is preferable to use a microreactor as the reaction vessel. According to the microreactor, semiconductor nanoparticles can be continuously synthesized, and rapid cooling can be easily performed.

  In addition, although the method for producing semiconductor nanoparticles by the hot soap method has been described above, the luminescent material of the present embodiment has a plurality of metal compounds (metal compound A and metal in the pores of a porous template). You may manufacture by filling the solution containing a compound B) and a solvent, heating the said casting_mold | template with the said casting_mold | template, and performing the process (cooling process) of cooling a solution (reaction liquid) after a heating process. In this case, in the heating step, the metal compounds react with each other in the template and semiconductor nanoparticles are formed. Therefore, the particle size of the semiconductor nanoparticles can be adjusted according to the diameter of the pores. That is, even in this method, semiconductor nanoparticles having a uniform particle size can be easily obtained. In addition, the solvent used at this time, the heating temperature in the heating step, the heating time, and the like can be the same as those in the above-described hot soap method. The template preferably has a uniform pore diameter, and can be, for example, mesoporous silica.

  A template made of mesoporous silica can be produced as follows. First, a surfactant, a silica source such as tetraethoxysilane (hereinafter also referred to as “TEOS”), and an acid or base catalyst are mixed. Then, the silica source is subjected to a sol-gel reaction in a state where the surfactant forms micelles, that is, in a state where the silica source is adsorbed around the surfactant. Next, by firing this, the surfactant is thermally decomposed to obtain mesoporous silica having uniform pores. The pore diameter of mesoporous silica can be easily controlled by changing the alkyl chain length of the surfactant.

  Mesoporous silica can also be prepared by a method described in, for example, International Publication No. 2011-108649. Further, commercially available mesoporous silica may be applied. Examples of commercially available mesoporous silica include meso pure series manufactured by Mitsubishi Chemical and reagent grade mesoporous silica manufactured by Sigma-Aldrich.

  In addition, after forming semiconductor nanoparticles in the pores of the template, by performing the cooling step, it is possible to suppress the semiconductor nanoparticles from undergoing phase transition, and a semiconductor having an aspect ratio of 1.0 to 1.8. It becomes possible to increase the proportion of nanoparticles.

  The semiconductor nanoparticles sintered in the mold may be taken out from the mold by applying vibration by ultrasonic treatment or the like. Moreover, you may classify the semiconductor nanoparticle taken out from the casting_mold | template as needed.

(Process for producing shell layer)
The process for forming the shell layer is not particularly limited. For example, a step of adding a shell layer precursor or a complex-forming agent to a solution containing semiconductor nanoparticles and heating the solution can be performed. The precursor of the shell layer and the complex forming agent may be added to the solution after the above-described semiconductor nanoparticle production step, that is, the solution after quenching. In addition, after the semiconductor nanoparticles are prepared, the semiconductor nanoparticles may be isolated from the reaction solution, and the precursor of the shell layer or the complex forming agent may be added to a solution in which the semiconductor nanoparticles are dispersed in a desired solvent.

  The heating temperature and heating time at this time are appropriately selected according to the type of the shell layer, the thickness of the shell layer, and the like. From the viewpoint of suppressing the transition of the crystal structure of the semiconductor nanoparticles, the heating temperature is preferably lower than the heating temperature during the production of the semiconductor nanoparticles, preferably 100 ° C. to 320 ° C., and 200 to 300 It is preferable to set it as ° C. When the heating temperature is 100 ° C. or higher, the shell layer can be efficiently produced. In addition, when the heating temperature is excessively high, the transition of the crystal structure of the semiconductor nanoparticles tends to occur. However, when the temperature is lower than the heating temperature at the time of manufacturing the semiconductor nanoparticles and the temperature is 320 ° C. or less, the reaction is stably performed. It can be carried out. Moreover, heating time can be normally 10 second-1 hour, and it is more preferable that it is 1 to 30 minutes. If it is 10 seconds or less, the reaction between the metal compounds may not proceed completely. In addition, the particle size may be too large after 1 hour.

  The precursor of the shell layer is appropriately selected according to the desired composition of the shell layer. For example, when the shell layer is made of ZnS, a compound containing Zn and S can be used as a precursor of the shell layer. Examples of such compounds include zinc diethyldithiocarbamate, bis [bis (2-hydroxyethyl) dithiocarbamato] zinc, 2-mercaptopyridine N-oxide zinc, (toluene-3,4-dithiolato) zinc, dibenzyldithiocarbamine. Examples include zinc acid, zinc dibutyldithiocarbamate, zinc dimethyldithiocarbamate, and bis (tetrabutylammonium) bis (1,3-dithiol-2-thione-4,5-dithiolato) zinc complex. Of Zn and S, a metal compound containing only Zn (for example, zinc stearate) and sulfur may be used as the precursor of the shell layer.

  On the other hand, when the desired shell layer is MgS or CdS, a compound in which Zn of the compound containing Zn and S is replaced with Mg or Cd can be used as these precursors. When the desired shell layer is ZnSe or ZnTe, a compound in which S of the compound containing Zn and S is replaced with Se or Te can be used as the precursor.

  Moreover, the solvent and complex formation agent used at the time of preparation of a shell layer can be made to be the same as the solvent and complex formation agent used at the preparation process of the above-mentioned semiconductor nanoparticles.

  After the heating step, a cooling step for cooling the solution (reaction solution) may be performed. The temperature gradient during cooling of the reaction solution is not particularly limited, but is preferably 1 ° C./second or more, and more preferably 1.5 ° C./second or more.

  In addition, when the semiconductor nanoparticles are prepared using a template, a method of forming a shell layer in the template, and a method of forming a shell layer by taking out the semiconductor nanoparticles from the template after the semiconductor nanoparticles are prepared. Either method can be adopted. Further, the particles may be used after being taken out from the mold, or the entire template can be used as a wavelength conversion material without taking out the particles.

3. Use of light emitter The semiconductor nanoparticles contained in the light emitter of the above embodiment have a very high fluorescence quantum yield. Moreover, the particle diameter of each semiconductor nanoparticle is uniform, and there is little dispersion | variation in the chromaticity of the fluorescence which each semiconductor nanoparticle emits. Therefore, the light emitter of the above embodiment can be applied to various uses.

  Hereinafter, the case where the light emitter of the above embodiment is used as a material for a fluorescent probe, an LED device, a projection display wheel, a display device, and a photoelectric conversion device will be described. It is not limited to.

(1) Fluorescent probe In this embodiment, the above-described luminescent material is applied to a fluorescent probe for fluorescently labeling a target biomolecule. As shown in the image diagram of FIG. 2, the fluorescent probe includes a target-directing ligand 4 that specifically binds to a target biomolecule (antigen) 5 and a light emitter 3 that is bound to the target-directing ligand 4. It can have. The fluorescent probe may be dispersed in water or a buffer and used as a fluorescent probe dispersion.

  When a fluorescent probe or a fluorescent probe dispersion is administered to a living cell or biological tissue having a target biomolecule, the fluorescent probe specifically binds to or specifically adsorbs to the target biomolecule. Then, when excitation light (radiation) having a predetermined wavelength is irradiated to the position where the fluorescent probe is administered, a light emitter (semiconductor nanoparticle) included in the fluorescent probe is excited and emits fluorescence having a predetermined wavelength. Therefore, by detecting the fluorescence, it is possible to detect the position of the target biomolecule and grasp the detection amount.

  Such a fluorescent probe can be obtained by covalently bonding (for example, an amide bond) the functional group on the surface of the light emitter (semiconductor nanoparticle or shell layer) and the functional group of the target-directing ligand. A targeting ligand is a molecule having a function of specifically binding to a specific tissue or cell. The type of target-directing ligand is not particularly limited and is appropriately selected according to the target substance. Examples of target-directing ligands include:

(I) When the target is various marker proteins or peptides that are specifically expressed in diseased tissues or cells such as cancer, the targeting ligand is an antibody against these (for example, HER2 antibody, cancer-specific antibody, blood vessel Endothelial cell-specific antibody, tissue-specific antibody, phosphorylated protein antibody, etc.) or an affinity substance thereof, folic acid, transferrin, transferrin-binding peptide and the like.
(Ii) When the target is a sugar chain, the target-directing ligand can be a protein (for example, lectin) having a binding property to the sugar chain.
(Iii) Other target-directing ligands include, for example, cell membrane affinity substances, viral cell recognition sites, lipophilic tracers, virus particles having no replication function, and organelle affinity substances (eg, DNA, mitochondria, cytoskeleton) Molecule, Golgi apparatus, lysosome, endosome, autophagosome, etc.).

  As described above, the phosphor used in this embodiment has a high fluorescence quantum yield of each semiconductor nanoparticle. Moreover, the particle size of each semiconductor nanoparticle is uniform, and the color purity of the fluorescence emitted from the semiconductor nanoparticle is high. Therefore, the signal / noise ratio when the fluorescence spectrum measurement is performed can be sufficiently increased, and the position and amount of the target biomolecule can be accurately identified.

(2) LED device The present embodiment is an LED device using the above-described light emitter as a material for forming a wavelength conversion layer of the LED device. An example of a schematic cross-sectional view of the LED device of the present embodiment is shown in FIGS. 3 (a) and 3 (b). The LED device 50 includes a substrate 10, a light emitting element 20 disposed on the substrate 10, and a wavelength conversion layer 30 disposed on the emission surface of the light emitting element 20. In the LED device 50, a part of light emitted from the LED element 20 is converted into light having a specific wavelength by the wavelength conversion layer 30, so that the color of light emitted from the LED device 50 is set to a desired color. For example, when the LED element 20 emits blue light (light of about 420 nm to 485 nm), after the wavelength conversion layer 30 includes a light emitting body that emits yellow fluorescence when excited by blue light, the light passes through the wavelength conversion layer 30. The light can be white.

  In addition, the wavelength of the light which LED element 20 radiate | emits will not be restrict | limited especially if it is a wavelength which can excite the above-mentioned light-emitting body (semiconductor nanoparticle), It can be set as blue light, near ultraviolet light, etc. Further, the color of the fluorescence emitted from the light emitter (semiconductor nanoparticles) is not particularly limited, and may be any color such as red, green, blue, yellow, and the like. The combination of the color of light emitted from the LED element 20 and the color of fluorescence emitted from the semiconductor nanoparticles is appropriately selected according to the application of the LED device 50 and the like. Further, the wavelength conversion layer 30 may include only one type of light emitter, or may include two or more types.

  Here, the wavelength conversion layer 30 may be a layer in which a light emitter is bound by a binder. Further, the wavelength conversion layer 30 may be a layer covering the LED element 20 as shown in FIG. 3A, and is mounted on the LED element 20 as shown in FIG. 3B. It may be a placed film. In any embodiment, the binder is not particularly limited as long as it has light transmittance and can sufficiently bind the light emitter, and may be made of an inorganic material or made of a resin. It may be. The binder can be a transparent resin such as an epoxy resin or a silicone resin, or a translucent ceramic such as polysiloxane.

  Such a wavelength conversion layer 30 is obtained by applying the above-described phosphor and a composition containing the binder or a precursor thereof by a known method and curing the composition. The composition for forming the wavelength conversion layer 30 may contain a solvent as necessary.

  As described above, the above-described light emitter has a high fluorescence quantum yield of each semiconductor nanoparticle. Further, since the semiconductor nanoparticles have a uniform particle size, the color and brightness of the fluorescence emitted by the semiconductor nanoparticles are uniform. Therefore, fluorescence with high color purity can be easily obtained, and the chromaticity of light emitted from the LED device can be easily adjusted to a desired range.

(3) Projection-type display device color wheel In this embodiment, the above-described light emitter is used as a material for a light adjustment layer of a projection-type display device color wheel (hereinafter also referred to as “color wheel”). . A schematic diagram of a projection display device incorporating a color wheel is shown in FIG. The projection display device 120 includes at least a light source 110, a color wheel 100, and a projection optical system 114. Light emitted from the light source 100 is collected by the lens 111 and the like, and is applied to the color wheel 100 described above. At this time, light from the light source is diffused or wavelength-converted by a light adjustment layer (not shown) of the color wheel 100. The light transmitted through the color wheel 100 is guided to the projection optical system 114 via the lens 112, the mirror 113, and the like, and is projected by the projection optical system 114 to display an image on the screen. The light emitter described above is included in the color wheel as a material for the color wheel of such a projection display device, more specifically, as a material for converting light from the light source 110 into light of other wavelengths. Can do.

  As shown in FIG. 4B, the color wheel 100 of the projection display device includes a light adjustment layer disposed around the rotation center. In the present embodiment, the color wheel 100 has a structure in which a substrate 101 and a light adjustment layer 102 including a light emitter are laminated. The color wheel 100 is installed between the light source 110 and the projection optical system 114 in the projection display device, and diffuses the light from the light source 110 or converts the light from the light source 110 into light of another specific wavelength. It performs the function to do.

  Although only one type of light adjustment layer may be formed on the color wheel 100, as shown in FIG. 4B, a plurality of types of light adjustment layers 102a to 102c are formed on one color wheel 100. May be. For example, when the light from the light source of the projection display device is ultraviolet light, the light adjustment layer 102a including a light emitting body that emits blue light by receiving ultraviolet light, and light emission that emits green light by receiving ultraviolet light Even if only one type of light source is used, the light adjustment layer 102b including the body and the light adjustment layer 102c including the light emitter that emits red light upon receiving ultraviolet light can be used. The three primary colors can be reproduced. Note that the type of the light adjustment layer 102 included in the color wheel 100, the region where the light adjustment layer 102 is formed, and the like, the type of the projection display device 120, the wavelength of light emitted from the light source 110, and the projection display device. It is appropriately selected according to the structure and the like.

  Here, the light adjusting layer 102 may be a layer in which a light emitter is bound by a binder. The light adjustment layer 102 may be a film-like member having self-supporting properties. The binder included in the light adjustment layer 102 can be the same as the binder included in the wavelength conversion layer of the LED device described above. Moreover, the formation method of the light adjustment layer 102 can be the same as the formation method of the wavelength conversion layer of the LED device.

  As described above, the phosphor used in this embodiment has a high fluorescence quantum yield of each semiconductor nanoparticle. Moreover, since the semiconductor nanoparticles have a uniform particle size, the color and brightness of the fluorescence emitted by the semiconductor nanoparticles tend to be uniform. Therefore, it is easy to obtain fluorescence of a desired color by the light adjustment layer, and the color reproducibility of the image projected from the projection display device is improved.

  In the above description, the case where the color wheel is a transmissive color wheel has been described as an example. However, the light emitter described above can also be applied to a reflective color wheel.

(4) Display device In the present embodiment, the above-described light emitter is used in a backlight device mounted on various display devices and the like. Specifically, as a material for a wavelength conversion layer of the backlight device. It is what was used. Examples of the backlight device of the present embodiment are shown in FIGS. The backlight device 200 is a planar light emitting device provided on the back surface of a liquid crystal panel (not shown), for example, and irradiates the liquid crystal panel with light. The semiconductor nanoparticles included in the above-described light emitter are materials for wavelength conversion layers of such a backlight device, more specifically, for converting a part of light from the light source 202 to light of other wavelengths. Can be applied to the material. In the backlight device 200, the light emitted from the light source 202 is converted by the wavelength conversion layer 201, so that light of a desired color can be irradiated onto the liquid crystal panel.

  The configuration of the backlight device 200 is appropriately selected according to the application. For example, as illustrated in FIG. 5A, a configuration including a light source 202 and a wavelength conversion layer 201 disposed on the side of the light source 202 can be employed. Further, for example, as shown in FIG. 5B and FIG. 5C, a light guide 203 for diffusing light emitted from the light source 202 or light converted in wavelength by the wavelength conversion layer 201 is provided. It can also be configured. In this case, light emitted from the light source 202 or the wavelength conversion layer 201 is diffused by the light guide 203. Further, as shown in FIG. 5D, the light source 202 and the wavelength conversion layer 201 may be arranged with a gap therebetween.

  Here, the wavelength conversion layer 201 can be a layer in which a light emitter is bound by a binder. The wavelength conversion layer 201 may be a film-like member having self-supporting properties. The binder is not particularly limited as long as it has optical transparency and can sufficiently bind the light emitter. Such a binder can be the same as the binder included in the wavelength conversion layer of the LED device described above. Further, the method for forming the wavelength conversion layer 201 of the backlight device 200 can be the same as the method for forming the wavelength conversion layer of the LED device.

  As described above, the above-described light emitter has a high fluorescence quantum yield of each semiconductor nanoparticle. Further, since the semiconductor nanoparticles are uniform, the color and brightness of the fluorescence emitted by the semiconductor nanoparticles tend to be uniform. Therefore, it is easy to obtain fluorescence of a desired color by the wavelength conversion layer, and the chromaticity of light emitted from the backlight device is likely to fall within a desired range.

(5) Photoelectric conversion device This embodiment is a photoelectric conversion device using the above-described light emitter in the wavelength conversion layer of the photoelectric conversion layer. FIG. 6 illustrates an example of a photoelectric conversion device. The photoelectric conversion device 300 has a structure in which an electrode layer 302, a P-type semiconductor layer 303, an N-type semiconductor layer 304, a transparent electrode layer 305, and a wavelength conversion layer 310 are stacked on a substrate 301. The above-described light emitter can be used as a material for forming the wavelength conversion layer 310. More specifically, a material for converting light entering the photoelectric conversion layer into light having a desired wavelength can be used.

  In a general photoelectric conversion device, only light of a specific wavelength contained in sunlight can be used for photoelectric conversion. Therefore, by including a light emitter in the wavelength conversion layer 310 of the photoelectric conversion device 300, the power generation efficiency of the photoelectric conversion device 300 can be improved. For example, the semiconductor nanoparticles in the light emitter are excited by light having a wavelength not used for photoelectric conversion to obtain fluorescence. As a result, the amount of light having a wavelength that can be used for photoelectric conversion increases, and the power generation efficiency of the photoelectric conversion device 300 is likely to increase.

  Here, the wavelength conversion layer 310 included in the photoelectric conversion device 300 can be a layer in which a light emitter is bound by a binder. The wavelength conversion layer 310 may be a film-like member having self-supporting properties. The binder is not particularly limited as long as it has optical transparency and can sufficiently bind a semiconductor. Such a binder can be the same as the binder included in the wavelength conversion layer of the LED device described above. Moreover, the formation method of the wavelength conversion layer 310 of the photoelectric conversion apparatus 300 can also be made to be the same as the formation method of the wavelength conversion layer of the LED device.

  Hereinafter, specific embodiments of the present invention will be described in detail. However, the scope of the present invention is not limited by this. In addition, although the display of "part" is used in an Example, unless otherwise indicated, "part by mass" is represented.

Example 1
0.01 parts of octadecene: Preparation CsCO ₃ of-semiconductor nanoparticle 0.3 parts 0.02 parts of oleic acid were mixed under a nitrogen atmosphere was maintained at 130 ° C., to prepare a semiconductor nanoparticle precursor liquid 1. Further, SnBr ₂ : 0.03 part, octadecene: 3 part, oleic acid: 0.3 part, oleylamine: 0.3 part are mixed in a nitrogen atmosphere maintained at 130 ° C., and the semiconductor nanoparticle precursor liquid 2 is mixed. Prepared. Then, after adding the semiconductor nanoparticle precursor liquid 1 to the semiconductor nanoparticle precursor liquid 2 heated to 240 ° C. and mixing for 5 minutes, the mixture is cooled in ice water and made of a compound represented by CsSnBr _3. Nanoparticles were obtained. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second.

(Example 2)
The same procedure as in Example 1 was performed except that the temperature at the time of mixing the semiconductor nanoparticle precursor liquid 1 and the semiconductor nanoparticle precursor liquid 2 was changed to 130 ° C. during the production of the semiconductor nanoparticles in the examples. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

(Example 3)
In Example 1, SnBr used as the raw material in the semiconductor nanoparticle during the production _2: 0.03 parts SnCl _3: was changed to 0.02 parts, was performed in the same manner as in Example 1. As a result, semiconductor nanoparticles composed of a compound represented by CsSnCl ₃ were obtained.

Example 4
In Example 2, SnBr used as the raw material in the semiconductor nanoparticle during the production _2: 0.03 parts of _SnI 3: was changed to 0.04 parts, was carried out as in Example 2. This gave a semiconductor nanoparticle comprising a compound represented by CsSnI _3.

(Example 5)
In Example 1, SnBr used as the raw material in the semiconductor nanoparticle during the production _2: 0.03 parts SnBr _2: 0.015 parts and SnCl _3: was changed to 0.01 part, performed in the same manner as in Example 1 It was. This _gave a semiconductor nanoparticle comprising a compound represented by _{CsSnCl 1.5 Br} 1.5.

(Example 6)
The same operation as in Example 3 was performed except that the temperature at the time of mixing the semiconductor nanoparticle precursor liquid 1 and the semiconductor nanoparticle precursor liquid 2 during the production of the semiconductor nanoparticles in Example 3 was changed to 320 ° C. As a result, semiconductor nanoparticles composed of a compound represented by CsSnCl ₃ were obtained.

(Example 7)
-Production of template (C18 mesoporous silica) Tetraethoxysilane (TEOS), hydrochloric acid aqueous solution (pH 1.0) and n-octadecyltrimethylammonium chloride were mixed at a molar ratio of 1: 5: 1, and the mixture was stirred at 60 ° C for 24 hours. The gel was obtained by standing for a period of time. The obtained gel was isolated, dried at 60 ° C. for 24 hours, and then sintered at 600 ° C. for 3 hours to obtain mesoporous silica having a pore diameter of about 3.2 nm. The numerical value “18” in “C18 mesoporous silica” represents the chain length of the hydrocarbon group of the surfactant used when producing the template silica, and is a numerical value that is an index of the pore size of the template. is there.

0.01 parts of octadecene: Preparation CsCO ₃ of-semiconductor nanoparticle 0.3 parts 0.02 parts of oleic acid were mixed under a nitrogen atmosphere was maintained at 130 ° C., to prepare a semiconductor nanoparticle precursor liquid 1. Further, SnBr ₂ : 0.03 part, octadecene: 3 part, oleic acid: 0.3 part, oleylamine: 0.3 part are mixed in a nitrogen atmosphere maintained at 130 ° C., and the semiconductor nanoparticle precursor liquid 2 is mixed. Prepared. Then, after adding the semiconductor nanoparticle precursor liquid 2 to the container containing 10 parts of the mesoporous silica and heating to 240 ° C., the semiconductor nanoparticle precursor liquid 1 is added and mixed for 5 minutes, and then the mixture is put into ice water. And cooled to obtain semiconductor nanoparticles composed of a compound represented by CsSnBr ₃ in mesoporous silica. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second.
Subsequently, the mesoporous silica dispersion containing the semiconductor nanoparticles was subjected to ultrasonic treatment for 1 hour to take out the semiconductor nanoparticles from the mesoporous silica.

(Example 8)
In Example 1, SnBr used as the raw material in the semiconductor nanoparticle during the production _2: 0.03 parts SnBr _2: 0.025 parts of _SnF 3: was changed to 0.004 parts, performed in the same manner as in Example 1 It was. This _gave a semiconductor nanoparticle comprising a compound represented by _CsSnF 0.5 _{Br 2.5.}

Example 9
In Example 1, CsCO used as a starting material in the semiconductor nanoparticle during the production _3: 0.01 parts _Rb 2 _CO 3: was changed to 0.007 parts, was performed in the same manner as in Example 1. This gave a semiconductor nanoparticle comprising a compound represented by RbSnBr _3.

(Example 10)
In Example 2, SnBr used as the raw material in the semiconductor nanoparticle during the production _2: 0.03 parts of GeBr _4: was changed to 0.04 parts, was performed in the same manner as in Example 1. This gave a semiconductor nanoparticle comprising a compound represented by CsGeBr _3.

(Example 11)
Preparation of Semiconductor Nanoparticles CsCO ₃ : 0.01 part, Octadecene: 0.3 part, Trioctylphosphine: 0.04 part are mixed in a nitrogen atmosphere maintained at 130 ° C. to prepare a semiconductor nanoparticle precursor liquid 1 did. SnBr ₂ : 0.03 part, Octadecene: 3 part, Trioctylphosphine: 0.6 part, Oleylamine: 0.3 part are mixed in a nitrogen atmosphere maintained at 130 ° C. to prepare a semiconductor nanoparticle precursor liquid 2 did. And after adding the semiconductor nanoparticle precursor liquid 1 to the semiconductor nanoparticle precursor liquid 2 heated at 240 degreeC and mixing for 5 minutes, the said mixture was put into ice water and cooled, and the semiconductor nanoparticle was obtained. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

(Example 12)
CsBr: 0.025 parts, octadecene: 3 parts, oleic acid 0.03 parts, oleylamine: 0.3 parts were mixed in a nitrogen atmosphere maintained at 130 ° C. to prepare a semiconductor nanoparticle precursor liquid 1. SnBr ₂ : 0.03 part, octadecene: 3 part, oleic acid: 0.3 part, oleylamine: 0.3 part were mixed in a nitrogen atmosphere maintained at 130 ° C. to prepare a semiconductor nanoparticle precursor liquid 2. . And after adding the semiconductor nanoparticle precursor liquid 1 to the semiconductor nanoparticle precursor liquid 2 heated at 240 degreeC and mixing for 5 minutes, the said mixture was put into ice water and cooled, and the semiconductor nanoparticle was obtained. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

(Example 13)
CsCO ₃ : 0.005 part, octadecene: 0.15 part, and oleic acid 0.01 part were mixed in a nitrogen atmosphere maintained at 130 ° C. to prepare a semiconductor nanoparticle precursor liquid 1. SnBr ₂ : 0.015 part, octadecene: 1.5 part, oleic acid: 0.15 part, oleylamine: 0.15 part are mixed in a nitrogen atmosphere maintained at 130 ° C., and the semiconductor nanoparticle precursor liquid 2 is mixed. Prepared. And after adding the semiconductor nanoparticle precursor liquid 1 to the semiconductor nanoparticle precursor liquid 2 heated at 240 degreeC and mixing for 5 minutes, the said mixture was put into ice water and cooled, and the semiconductor nanoparticle was obtained. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 2.5 ° C./second. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

(Comparative Example 1)
A bulk body was produced by heating for 150 hours under a nitrogen atmosphere in which CsBr: 0.8 part and SnBr ₂ : 1 part were maintained at 300 ° C. The obtained bulk body was crushed with a ball mill to obtain a luminous body. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

(Comparative Example 2)
· Preparation CsCO ₃ of semiconductor nanoparticles: 0.01 parts of octadecene 0.3 parts to prepare a semiconductor nanoparticle precursor liquid 1 were mixed under a nitrogen atmosphere was maintained 0.02 parts of oleic acid 130 ° C.. Further, SnBr ₂ : 0.03 part, octadecene: 0.3 part, oleic acid: 0.3 part, oleylamine: 0.3 part were mixed in a nitrogen atmosphere maintained at 130 ° C., and the semiconductor nanoparticle precursor liquid 2 Was prepared. And after adding the semiconductor nanoparticle precursor liquid 1 to the semiconductor nanoparticle precursor liquid 2 heated at 240 degreeC and mixing for 5 minutes, it cooled in air and obtained the semiconductor nanoparticle. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 0.5 ° C./second. This gave a semiconductor nanoparticle comprising a compound represented by CsSnBr _3.

[Evaluation]
About the semiconductor nanoparticles produced in Examples 1 to 13 and Comparative Examples 1 and 2, the aspect ratio, the ratio of particles having an aspect ratio of 1.0 to 1.8 with respect to the total amount of semiconductor nanoparticles, and the variation in particle diameter Values were determined by the following methods. The results are shown in Table 1.

(Measuring method of aspect ratio of semiconductor nanoparticles and fluctuation value (CV value) of major axis α)
About 100 semiconductor nanoparticles produced in each Example and Comparative Example, 100 images were observed using a transmission electron microscope (TEM) (JEM-2500SE, manufactured by JEOL). And the average value of major axis alpha and minor axis beta of 100 semiconductor nanoparticles was computed, respectively. Based on the values of the major axis α and the minor axis β obtained, the aspect ratio (α / β) of the semiconductor nanoparticles was calculated. Further, when measuring the major axis α by TEM observation, the fluctuation value (CV value = standard deviation / average value of major axis α) of the major axis α of each particle was also calculated.

  As shown in Table 1, when rapidly cooling the semiconductor nanoparticles, the aspect ratio (α / β) tends to be sufficiently small, and the proportion of particles having an aspect ratio of 1.8 or less is 50% by mass or more. (Examples 1 to 13). On the other hand, when it was gradually cooled, it was difficult to sufficiently reduce the aspect ratio (Comparative Example 2). Moreover, also when it crushed with the ball mill (comparative example 1), the CV value became large and it was difficult to make the particle diameter uniform.

  In particular, when the synthesis temperature is high and the cooling rate is fast (Examples 1, 3, 5-9, 11-13), the aspect ratio is about 1.4, that is, the crystal structure is cubic. It was easy to obtain semiconductor nanoparticles.

(Example 14)
Oleylamine: 0.8 part and zinc diethyldithiocarbamate: 0.02 part were mixed with the semiconductor nanoparticle dispersion prepared in Example 1 and mixed for 1 hour in a nitrogen atmosphere maintained at 240 ° C. Thereafter, the aqueous solution is mixed at 240 ° C. for 1 hour, rapidly cooled with ice water, and a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ is obtained. It was. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second.

(Example 15)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 2 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

(Example 16)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 3 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. As a result, a phosphor dispersion having a shell layer made of ZnS around the semiconductor nanoparticles made of the compound represented by CsSnCl ₃ was obtained.

(Example 17)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 4 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnI ₃ was obtained.

(Example 18)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 5 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. As a result, a phosphor dispersion having a shell layer made of ZnS around the semiconductor nanoparticles made of a compound represented by CsSnCl _1.5 Br _1.5 was obtained.

(Example 19)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 6 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. As a result, a phosphor dispersion having a shell layer made of ZnS around the semiconductor nanoparticles made of the compound represented by CsSnCl ₃ was obtained.

(Example 20)
Semiconductor nanoparticles were prepared in a mesoporous silica template by the same procedure as in Example 7. Next, oleylamine: 0.8 part and diethyldithiocarbamate: 0.02 part were mixed with the prepared dispersion of the template containing semiconductor nanoparticles, and mixed for 1 hour in a nitrogen atmosphere maintained at 240 ° C. Thereafter, the aqueous solution is mixed at 240 ° C. for 1 hour, rapidly cooled with ice water, and a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ is obtained. It was. The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second. Subsequently, the mesoporous silica dispersion containing the semiconductor nanoparticles was subjected to ultrasonic treatment for 1 hour to take out the semiconductor nanoparticles from the mesoporous silica.

(Example 21)
A solution in which cadmium stearate and sulfur were dissolved in 1 part of octadecene was added to the dispersion of semiconductor nanoparticles prepared in Example 4. At this time, the mass ratio of Cs, Cd, and S in the semiconductor nanoparticles was adjusted to 1: 1: 1. Then, the mixture was stirred at 240 ° C. for 30 minutes and quenched with ice water to obtain a phosphor dispersion having a shell layer made of CdS around the semiconductor nanoparticles made of the compound represented by CsSnI ₃ . The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second.

(Example 22)
A solution in which stearic zinc and sulfur were dissolved in 1 part of octadecene was added to the dispersion of semiconductor nanoparticles prepared in Example 1. At this time, the mass ratio of Cs, Zn, and S in the semiconductor nanoparticles was adjusted to 1: 1: 1. Then, the mixture was stirred at 240 ° C. for 30 minutes and quenched with ice water to obtain a phosphor dispersion having a shell layer made of CdS around the semiconductor nanoparticles made of the compound represented by CsSnBr ₃ . The temperature gradient when cooling from 240 ° C. to 50 ° C. was 1.5 ° C./second.

(Example 23)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 8 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. _Thus, the periphery of the semiconductor nanoparticles comprising a compound represented by _CsSnF 0.5 _{Br 2.5,} having a shell layer made of ZnS, to obtain a dispersion of the light emitter.

(Example 24)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 9 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around the semiconductor nanoparticles made of the compound represented by RbSnBr ₃ was obtained.

(Example 25)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 10 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around the semiconductor nanoparticles made of a compound represented by CsGeBr ₃ was obtained.

(Example 26)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 11 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

(Example 27)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 12 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

(Example 28)
A shell layer was prepared in the same manner as in Example 14 except that the semiconductor nanoparticle dispersion prepared in Example 13 was used instead of the semiconductor nanoparticle dispersion prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

(Comparative Example 3)
A shell layer was prepared in the same manner as in Example 14 except that the dispersion of crushed particles prepared in Comparative Example 1 was used instead of the dispersion of semiconductor nanoparticles prepared in Example 1. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

(Comparative Example 4)
The semiconductor nanoparticle dispersion prepared in Comparative Example 2 was used in place of the semiconductor nanoparticle dispersion prepared in Example 1, and the temperature gradient when cooling from 240 ° C. to 50 ° C. was 0. A shell layer was produced in the same manner as in Example 14 except that the temperature was set to 5 ° C./second. Thus, a phosphor dispersion having a shell layer made of ZnS around a semiconductor nanoparticle made of a compound represented by CsSnBr ₃ was obtained.

[Evaluation]
For the phosphors produced in Examples 14 to 28 and Comparative Examples 3 and 4, the fluorescence quantum yield, the emission peak wavelength, the half-value width of the emission peak wavelength, the signal noise ratio, and the fluorescence intensity at the time of low concentration staining are as follows. Each was measured by the method. The evaluation results are shown in Table 2.

(Evaluation of fluorescence quantum yield)
The fluorescence quantum yield of the semiconductor nanoparticles was measured using an absolute PL quantum yield measuring apparatus (Quantaurus-QY C11347-01, manufactured by Hamamatsu Photonics). And the fluorescence quantum yield was evaluated on the following reference | standard. In addition, it means that the sensitivity of the semiconductor nanoparticle which a light-emitting body contains is so high that the value of a fluorescence quantum yield is large.
A: Quantum yield of 50% or more O: Quantum yield of 40% or more and less than 50% Δ: Quantum yield of 30% or more and less than 40% ×: Quantum yield of less than 30%

(Evaluation of emission peak wavelength of light emitter and half-value width of emission peak wavelength)
About each light-emitting body, the fluorescence spectrum measurement was performed using the fluorometer (F-7000; Hitachi Ltd. make), and the half value width of the light emission peak wavelength was evaluated on the following reference | standard. The full width at half maximum (FWHM) is the width of the wavelength at which the relative intensity is 50% when the intensity at the peak of the emission peak wavelength of the relative intensity is 100% in the fluorescence spectrum distribution. is there. In addition, it means that a peak is sharp, so that the value of a half value width is small.
○: Half width is 50 nm or less Δ: Half width is more than 50 nm and 60 nm or less ×: Half width is more than 60 nm

(Evaluation of signal / noise ratio (S / N) when a phosphor is used as a fluorescent probe)
10 mg of the phosphor prepared in Examples 14 to 28 and Comparative Examples 3 and 4 were dispersed in tetrahydrofuran (THF), and 0.2 g of 3-mercaptopropionic acid was added. Thereby, carboxylic acid was introduced into the surface of the luminescent material, and the surface was changed from hydrophobic to hydrophilic. Then, 50 μL of N, N′-dicyclohexylcarbodiimide 0.002 g and HER2 recognition antibody 4B5 (manufactured by Roche) were added to 4.5 g of the dispersion, and the mixture was vortexed for 1 minute and left for 1 hour. did. As a result, the carboxylic acid on the surface of the illuminant and the amino group end of the antibody (target-directed ligand) were dehydrated and condensed to obtain a fluorescent probe (luminant-antibody complex) in which the illuminant was bound to the antibody. . Finally, an appropriate amount of 0.1 mol / L phosphate buffer (pH 7.4, manufactured by Nacalai Tesque) was added to prepare a 0.1 mass% phosphate buffer dispersion (1) of the fluorescent probe.

To the breast cancer cell slice (HER2 IHC, manufactured by Pathology Laboratories) in which the HER2 protein was expressed on the cell membrane, the phosphoric acid buffer dispersion of the fluorescent probe prepared above was dropped and left at 4 ° C. for 40 minutes. Then, it was immersed in the phosphate buffer tank and the excess fluorescent probe was removed. Subsequently, the cells were immersed in an ethanol bath and a xylene bath in this order, and the cell slices were made into a low polarity solvent environment. Subsequently, cell samples were encapsulated with an encapsulant (Enterlan New, manufactured by Merck) to prepare an observation sample. The observation sample was observed using a fluorescence microscope (manufactured by Olympus) at an excitation wavelength of 365 nm. At this time, whether or not the fluorescent probe correctly recognizes HER2 specifically expressed in the cell membrane part, the “fluorescence intensity in the cell membrane part / fluorescence intensity in the whole cell” is expressed as a signal / noise ratio (S / N). And evaluated according to the following criteria.
◎: S / N is 0.98 or more ○: S / N is 0.95 or more and less than 0.98 Δ: S / N is 0.92 or more and less than 0.95 ×: S / N is less than 0.92

(Evaluation of fluorescence intensity at low concentration staining)
A 0.1 mass% phosphoric acid buffer dispersion (1) of a phosphor probe was prepared by the same method as the signal / noise ratio evaluation described above. In the same manner as described above, cell section staining and fluorescence microscope observation were performed. And the fluorescence intensity of the cell membrane part of Example 14 was set to 100, and the fluorescence intensity of each Example and a comparative example was evaluated on the following references | standards as a relative value with respect to the said value.
A: The relative value of the fluorescence intensity of the cell membrane part is 0.95 or more. O: The relative value of the fluorescence intensity of the cell membrane part is 0.90 or more and less than 0.95. Δ: The relative value of the fluorescence intensity of the cell membrane part is 0.85 or more and less than 0.90. X: The relative value of the fluorescence intensity of the cell membrane is less than 0.85

(Measurement of ratio of lattice constant)
For the phosphors produced in Example 17 and Comparative Example 21, the lattice constant of the semiconductor nanoparticles and the lattice constant of the shell layer were measured by XRD (X-ray diffraction), and the ratio of these (the lattice constant of the shell layer / semiconductor). The lattice constant of the nanoparticles was calculated.

  As shown in Table 2, when the aspect ratio of the semiconductor nanoparticles was 1.8 or less, the yield of fluorescent particles was high (Examples 14 to 28). Moreover, in these examples, the variation coefficient of the major axis α of the semiconductor nanoparticles was 40% or less, all had a narrow half width, and the signal / noise ratio and the fluorescence intensity were sufficiently high (Examples 14 to 28). In particular, in the case of a light emitting body (Examples 14, 16, 18-20, 22-24, 26-28) having semiconductor nanoparticles whose semiconductor nanoparticles have an aspect ratio of about 1.4, that is, a crystal structure. The fluorescence quantum yield was high.

  On the other hand, a phosphor including semiconductor nanoparticles having an aspect ratio exceeding 1.8 had a low quantum yield, a wide half-value width of an emission peak, and a low signal / noise ratio (Comparative Examples 3 and 4).

  The semiconductor nanoparticles contained in the phosphor of the present invention have a very high fluorescence quantum yield and a high color purity of emitted light. Therefore, the light emitter of the present invention can be applied to various uses such as a fluorescent probe and an illumination device.

DESCRIPTION OF SYMBOLS 3 Semiconductor nanoparticle 4 Target-directed ligand 5 Target biomolecule 10 Substrate 20 LED element 30 Wavelength conversion layer 50 LED device 100 Color wheel 101 Substrate 102 Light adjustment layer 110 Light source 111, 112 Lens 113 Mirror 114 Projection optical system 120 Projection display Device 200 Backlight device 201 Wavelength conversion layer 202 Light source 203 Light guide 300 Photoelectric conversion device 301 Substrate 302 Electrode layer 303 P-type semiconductor layer 304 N-type semiconductor layer 305 Transparent electrode layer 310 Wavelength conversion layer

Claims (22)

General formula (1) M1 _m1 M2 _m2 X _x
(In general formula (1),
M1 represents one or more elements selected from the group consisting of Li, Na, K, Rb, and Cs;
M2 represents one or both of Ge and Sn,
X represents one or more elements selected from the group consisting of F, Cl, Br, and I;
m1 represents a value in the range of 0.7 to 1.3;
m2 represents a value in the range of 0.7 to 1.3;
x represents a value in the range of 2.0 to 4.0)
Is a light emitter including a plurality of semiconductor nanoparticles made of a compound represented by:
The semiconductor nanoparticle having an aspect ratio (α / β) of 1.0 to 1.8 with respect to the total number of the semiconductor nanoparticles included in the light emitter, where α is the major axis of the semiconductor nanoparticles and β is the minor axis. The ratio of the number of particles is 50% or more,
The luminous body whose variation coefficient of major axis alpha of said semiconductor nanoparticle is 40% or less. The ratio of the number of the semiconductor nanoparticles having the aspect ratio of 1.0 to 1.8 to the total number of the semiconductor nanoparticles included in the light emitter is 70% or more.
The light emitter according to claim 1. The ratio of the number of the semiconductor nanoparticles having the aspect ratio of 1.0 to 1.5 with respect to the total number of the semiconductor nanoparticles included in the light emitter is 70% or more.
The light emitter according to claim 1 or 2. The variation coefficient of the major axis α of the semiconductor nanoparticles is 20% or less.
The light emitter according to any one of claims 1 to 3. The semiconductor nanoparticles have an emission peak wavelength in a wavelength range of 400 to 800 nm.
The light emitter according to any one of claims 1 to 4. The semiconductor nanoparticles have an emission peak wavelength in a wavelength range of 400 to 700 nm.
The light emitter according to any one of claims 1 to 5. The half-value width of the emission peak of the semiconductor nanoparticles is 60 nm or less.
The light emitter according to any one of claims 1 to 6. The semiconductor nanoparticles are coated with a shell layer;
The light emitter according to any one of claims 1 to 7. The ratio of the lattice constant of the shell layer to the lattice constant of the semiconductor nanoparticles is 70% or more and 130% or less.
The light emitter according to any one of claims 1 to 8. A method for producing a light emitter according to any one of claims 1 to 9,
A heating step of heating a solution containing a plurality of metal compounds and a solvent;
A cooling step for cooling the solution;
The manufacturing method of a light-emitting body containing this. The heating step is a step of heating the solution to 120 ° C. or higher,
The said cooling process is a manufacturing method of the light-emitting body of Claim 10 which is a process of cooling the said solution with the temperature gradient of 1 degree-C / sec or more. A method for producing a light emitter according to any one of claims 1 to 9,
Filling a solution containing a plurality of metal compounds and a solvent into the pores of a porous mold and heating;
A cooling step for cooling the solution;
The manufacturing method of a light-emitting body containing this. The light emitter according to any one of claims 1 to 9,
A targeting ligand bound to the illuminant;
A fluorescent probe.   The targeting ligand is an antibody or an affinity substance thereof, a cell membrane affinity substance, a viral cell recognition site, a lipophilic tracer, a virus particle having no replication function, an organelle affinity substance, folic acid, transferrin, transferrin-binding peptide The fluorescent probe according to claim 13, which is one or more molecules selected from the group consisting of a protein having a binding property to a sugar chain. The functional group on the surface of the phosphor and the functional group of the target-directing ligand are covalently bonded.
The fluorescent probe according to claim 13 or 14. The fluorescent probe according to any one of claims 13 to 15 is dispersed in water or a buffer solution.
Fluorescent probe dispersion. An LED element, and a wavelength conversion layer disposed on the light emission surface of the LED element,
The wavelength conversion layer includes the light emitter according to any one of claims 1 to 9,
LED device. The wavelength conversion layer is made of a wavelength conversion film containing the light emitter and a binder,
The LED device according to claim 17. A color wheel for a projection display device including a light adjustment layer arranged around a rotation center, wherein the light adjustment layer includes the light emitter according to any one of claims 1 to 9.
Color wheel for projection display devices. Including the light emitting body according to any one of claims 1 to 9 and a binder,
Wavelength conversion film. The wavelength conversion film according to claim 20 is included,
Display device. It has a wavelength conversion film according to claim 20.
Photoelectric conversion device.

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