Method for producing chalcogenide perovskite particles, and chalcogenide perovskite particles

Abstract

Provided is a method for producing chalcogenide perovskite particles containing chalcogenide perovskite, wherein a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid are reacted in a liquid phase in a solvent.

Description

Method for producing chalcogenide perovskite particles and chalcogenide perovskite particles

[0001] This invention relates to a method for producing chalcogenide perovskite particles and to chalcogenide perovskite particles.

[0002] In recent years, semiconductor light-emitting materials have been widely used as light-emitting materials in lighting and display devices, as well as as wavelength conversion (color conversion, downconversion) elements and as photoelectric conversion materials in photoelectric conversion elements. These fields require materials with high durability (e.g., stability against water, oxygen, heat, etc.) and high light absorption. For this reason, chalcogenide perovskites have attracted attention as this type of semiconductor light-emitting material because they have superior durability and a high light absorption coefficient compared to other materials, and do not contain harmful metals such as cadmium (see, for example, Non-Patent Documents 1 and 2 and Patent Documents 1 and 2).

[0003] For example, Non-Patent Documents 1 and 2 disclose chalcogenide perovskites synthesized by solid-phase synthesis. While the synthesis of fine particles by solid-phase synthesis is a widely known method, it has problems such as the ease with which impurities are introduced during the synthesis process and significant particle aggregation. For this reason, it is difficult to miniaturize the particle size of particles obtained by solid-phase synthesis, and it is difficult to control the particle size and shape, resulting in a wide particle size distribution. Furthermore, solid-phase synthesis generally yields particles of micron size, and when these are further pulverized to nanoparticles, numerous defects occur on the surface and inside the particles, resulting in a significant decrease in fluorescence intensity.

[0004] In contrast, liquid-phase synthesis is attracting attention as a method that can solve the problems of the solid-phase synthesis method described above in the synthesis of fine particles. As an example of using liquid-phase synthesis, for example, Patent Document 1 discloses a method for producing semiconductor nanocrystalline particles in which a first metal precursor, a second metal precursor, and a chalcogen precursor are heated at a temperature of about 100°C to 400°C in the presence of an organic solvent and a ligand compound.

[0005] Furthermore, for example, Patent Document 2 discloses a method for producing chalcogenide perovskite particles with a crystallite size of less than 40 nm by a liquid-phase synthesis method.

[0006] U.S. Patent Application Publication No. 2019 / 0225883, Specification International Publication No. 2023 / 100919

[0007] VKRavi et al., “Colloidal BaZrS3 chalcogenide perovskite nanocrystals for thin film device fabrication”, The Royal Society of Chemistry, Nanoscale, 2021, Vol.13, p.1616-1623S. Filippone et al., “High densification of BaZrS3 powder inspired by the cold-sintering process”, Journal of Materials Research, 2021, Vol. 36, p.4404-4412

[0008] When this type of chalcogenide perovskite particle is applied to light-emitting or power-generating materials, variations in the particle size of the chalcogenide perovskite particles make it difficult to obtain stable properties in terms of emission wavelength and emission full width at half maximum (color purity). From this perspective, there is a need to reduce the variation in the particle size of each chalcogenide perovskite particle.

[0009] One aspect of the present invention is a method for producing chalcogenide perovskite particles containing a chalcogenide perovskite, comprising reacting a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid in a solvent in the liquid phase.

[0010] According to one aspect of the present invention, a manufacturing method is provided that can reduce the variation in the particle size of chalcogenide perovskite particles compared to conventional methods.

[0011] This is a graph showing an example of the relationship between the excitation energy and particle size of semiconductor particles. This is a table showing a list of synthesis conditions in the examples and comparative examples. (a) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 1, and (b) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 2. (a) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 3, and (b) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 4. (a) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 5, and (b) is a figure showing the TEM observation image of the first semiconductor nanoparticles of Example 6. This is a figure showing the TEM observation image of the first semiconductor nanoparticles of the comparative example. This is a figure showing the XRD measurement results of the thin film of the first semiconductor nanoparticles of the comparative example. This is a figure showing the XRD measurement results of the thin film of the second semiconductor nanoparticles of Example 7. This is a figure showing the XRD measurement results of the first semiconductor nanoparticles in solution of Example 5. This is a figure showing the XRD measurement results of the second semiconductor nanoparticles in solution of Example 8.

[0012] <Structure of Chalcogenide Perovskite Particles> The chalcogenide perovskite particles of this embodiment consist of chalcogenide perovskite and have an overall shape in the nanometer scale. The chalcogenide perovskite particles are applied, for example, as a light-emitting material or a power-generating material, absorbing incident excitation light and re-emitting (luminescing) light of different energies (wavelengths).

[0013] Here, chalcogenide perovskite is a compound having a perovskite-type crystal structure and containing chalcogen (a Group 16 element other than oxygen (S, Se, or Te)). In addition to chalcogen, chalcogenide perovskite contains two or more metal elements, such as transition metal elements and alkaline earth metal elements, as components of the perovskite-type crystal structure.

[0014] The perovskites described above represent a group of materials having a cubic crystal structure based on a Bch6 octahedron, represented by the chemical formula ABCh3, and can take on tetragonal or orthorhombic crystal structures with lattice distortion. Furthermore, several stable crystal structures have been computationally demonstrated for the same ABCh3 composition. These crystal structures range from those similar to perovskites to those quite different. In addition, there are derived structures such as the Ruddlesden-Popper type and Dion-Jacobson type layered perovskites based on the perovskite structure, and double perovskite crystal structures in which different elements are alternately arranged at the B site. In this specification, the above crystal structures are collectively referred to as the "perovskite crystal structure group."

[0015] The perovskite crystal structure group specifically includes materials with the following crystal structures: cubic perovskite, tetragonal perovskite, GdFeO3-type orthorhombic, YScS3-type orthorhombic, NH4CdCl3-type orthorhombic, BaNiO3-type hexagonal, FePS3-type monoclinic, PbPS3-type monoclinic, CeTmS3-type monoclinic, Ruddlesden-Popper-type layered perovskite, Dion-Jacobson-type layered perovskite, and double perovskite. Note that the crystal structure and electronic structure of perovskite crystal structures change depending on the composition and synthesis conditions, resulting in changes to photoelectronic properties and chemical properties. Therefore, the composition and conditions are selected to obtain a crystal structure suitable for the purpose.

[0016] For example, materials having cubic perovskites, tetragonal perovskites, GdFeO3-type orthorhombic perovskites, Ruddlesden-Popper-type layered perovskites, and double perovskite structures exhibit excellent photoelectronic and chemical properties. Furthermore, chemical stability can be further improved by adopting a Dion-Jacobson-type layered perovskite structure. In particular, materials having a GdFeO3-type orthorhombic perovskite crystal structure represented by ABCh3 (A = Group 2, B = Group 4) are known to possess excellent photoelectronic properties, including a high light absorption coefficient.

[0017] In this embodiment, the chalcogenide perovskite has a composition represented by, for example, the following formula (101) or (102). ABCh ３ ... (101) A’ ２ A ｎ－１ B ｎ Ch ３ｎ＋１ ... (102)

[0018] In formulas (101) and (102), A and A’ are each Mg, Ca, Sr, Ba, or a combination thereof in any ratio, B is Ti, Zr, Hf, or a combination thereof in any ratio, and Ch is S, Se, Te, or a combination thereof in any ratio. In formula (102), n is an integer of 1 or more and 10 or less. In formula (102), A and A’ may be the same as or different from each other.

[0019] In this embodiment, the chalcogenide perovskite may be a solid solution in which part or all of A, A’, B, and Ch are substituted with other elements in the composition represented by formula (101) or (102).

[0020] The chalcogenide perovskite (ABCh ３ ) represented by formula (101) exhibits, for example, a crystal structure of cubic perovskite, tetragonal perovskite, orthorhombic perovskite, or double perovskite. As an example, the chalcogenide perovskite represented by the chemical formula ABCh3 includes the following substances. In the following examples, Ch is selected from the dominant materials among the chalcogen elements (S, Se), A is selected from the dominant materials among the Group 2 elements (Sr, Ba), and B is selected from the dominant materials among the Group 4 elements (Zr, Hf). SrZrS3, SrZrSe3, SrHfS3, SrHfSe3, BaZrS3, BaZrSe3, BaHfS3, BaHfSe3

[0021] The chalcogenide perovskite (A’ ２ A ｎ－１ B ｎ Ch ３ｎ＋１) shows, for example, the crystal structure of a Ruddlesden-Popper type layered perovskite. As an example, the chemical formula (A' ２ A ｎ－１ B ｎ Ch ３ｎ＋１ The chalcogenide perovskites represented by ) include the following substances: Ch is selected from the dominant chalcogen elements (S, Se), A and A' are selected from the dominant elements of Group 2 (Sr, Ba), and B is selected from the dominant elements of Group 4 (Zr, Hf). Sr2Ba n-1 Zr n S 3n+1 , Sr2Ba n-1 Zr n See 3n+1 , Sr n+1 Zr n S 3n+1 , Sr n+1 Zr n See 3n+1 Ba2Sr n-1 Zr n S 3n+1 Ba2Sr n-1 Zr n See 3n+1 Ba n+1 Zr n S 3n+1 Ba n+1 Zr n See 3n+1 , Sr2Ba n-1 HF n S 3n+1 , Sr2Ba n-1 HF n See 3n+1 , Sr n+1 HF n S 3n+1 , Sr n+1 HF n See 3n+1 Ba2Sr n-1 HF n S 3n+1 Ba2Sr n-1 HF n See 3n+1 Ba n+1 HF n S 3n+1 Ba n+1 HF n See3n+1

[0022] Furthermore, the chemical formulas for chalcogenide perovskite are A''A'''B''2X7 and A''A2B''3X 10 It can also be expressed as A2BB'X6. In the above chemical formula, X represents a chalcogen element (S, Se, Te). A and A' represent elements of Group 2 (Ca, Sr, Ba), A'' represents elements of Group 1 (Li, Na, K, Rb, Cs), and A''' represents elements of Group 3 (rare earth elements) and Bi. B and B' represent elements of Group 4 (Ti, Zr, Hf), and B'' represents elements of Group 5 (V, Nb, Ta). Also, n is a positive integer. Note that A and A', and B and B' may be the same element. Furthermore, A, A', A'', A''', B, B', B'', and X include mixtures of elements from each group in any ratio.

[0023] These chalcogenide perovskites are (Sr x Ba 1-x ) (Zr y HF 1-y ) (S z See 1-z ) 3 or (Sr x’ Ba 1-x’ ) 2 (Sr x Ba 1-x ) n-1 (Zr y HF 1-y ) n (S z See 1-z ) 3n+1 It can also be expressed as (where x, x', y, and z are values ​​between 0 and 1, and n is a positive integer).

[0024] In chalcogenide perovskites, carrier concentration or crystal structure, as well as other physical and chemical properties, can be controlled by partial substitution of constituent elements with elements from the same or different groups. For example, elements in Group 1 can be substituted with elements from Groups 1 and 2, elements in Group 2 with elements from Groups 1, 2, and 3, elements in Group 3 with elements from Groups 2, 3, and 4, elements in Group 4 with elements from Groups 3, 4, and 5, and elements in Group 16 with elements from Groups 15, 16, and 17.

[0025] The following are some of the characteristics of chalcogenide perovskites as semiconductor materials: Chalcogenide perovskites have a large light absorption coefficient and excellent luminescence performance (luminescence efficiency, full width at half maximum). In addition, the light absorption coefficient profile of chalcogenide perovskites rises sharply at the band edge. Therefore, chalcogenide perovskites have the characteristic of high absorbance near the band gap edge.

[0026] Furthermore, chalcogenide perovskites have high chemical stability and excellent resistance to external environmental factors and stimuli such as air, moisture, heat, and light. In addition, chalcogenide perovskites are highly safe because they do not contain toxic elements, and they have low raw material costs because they do not contain rare metals.

[0027] Furthermore, although not particularly limited, chalcogenide perovskite particles may have their outer periphery covered with a shell. By providing a shell on the outer periphery of chalcogenide perovskite particles, for example, the durability of the particles can be further improved. In the following description, chalcogenide perovskite particles with their outer periphery covered with a shell will also be referred to as chalcogenite perovskite composites.

[0028] The shell material can be any material generally used for nanoparticle shells. For example, the shell material can be a group II-VI semiconductor, a group III-V semiconductor, a group III-VI semiconductor, a group I-III-VI semiconductor, a group I-II-IV-VI semiconductor, a group IV-VI semiconductor, a semiconductor containing group VI other than those listed above, a halide perovskite semiconductor, an oxide perovskite, an organic-inorganic perovskite, Si, a carbon material, silicon dioxide, a metal oxide, or a mixed crystal compound thereof. Examples of the metal oxides mentioned above include aluminum oxide, zirconium oxide, and zinc oxide. Alternatively, the shell may be formed with a chalcogenide perovskite different from the chalcogenide perovskite contained in the chalcogenide perovskite particles.

[0029] Furthermore, although not particularly limited, the chalcogenide perovskite may be surface-modified with ligands. Chalcogenide perovskite particles containing surface-modified chalcogenide perovskite can be easily dispersed in a dispersion medium. There are no restrictions on the type of ligand used to surface-modify the chalcogenide perovskite; any ligand commonly used for dispersing nanoparticles is acceptable. The dispersion medium for dispersing the chalcogenide perovskite particles may be a liquid or a solid such as a polymer compound.

[0030] Furthermore, examples of ligands used to surface-modify chalcogenide perovskites include one or more selected from the group consisting of amines, carboxylic acids, thiols, and phosphines.

[0031] The chalcogenide perovskite contained in the chalcogenide perovskite particles may have a portion of its surface replaced with other metals or elements such as oxygen or halogens, and a portion of its surface may be passivated. Furthermore, the substitution of elements on the chalcogenide perovskite surface may be suppressed by coating the outer periphery of the chalcogenide perovskite particles with a shell.

[0032] <Dimensions of chalcogenide perovskite particles> In this embodiment, the chalcogenide perovskite particles have a number-average particle size of, for example, 15 nm or less, as determined by transmission electron microscopy (TEM) observation.

[0033] While not particularly limited, the number-average particle size of the chalcogenide perovskite particles is preferably 13 nm or less, and more preferably 10 nm or less from the viewpoint of enabling control of the band gap by the manifestation of the quantum size effect described later. The number-average particle size of the chalcogenide perovskite particles is even more preferably 8.0 nm or less, and even more preferably 6.5 nm or less. Furthermore, from the viewpoint of further improving the luminescence efficiency due to the confinement effect described later, the number-average particle size of the chalcogenide perovskite particles is particularly preferably 6.0 nm or less, and even more preferably 5.0 nm or less.

[0034] Furthermore, the chalcogenide perovskite particles preferably have a number-average particle size of at least 1 nm, more preferably 2 nm or more, even more preferably 3 nm or more, even more preferably 3.5 nm or more, and particularly preferably 4 nm or more. The number-average particle size of the chalcogenide perovskite particles can be controlled, for example, by adjusting the concentration of each complex in the liquid phase and the reaction time when using a liquid-phase synthesis method.

[0035] While not particularly limited, the number-average particle size of the chalcogenide perovskite particles may be 1 nm to 15 nm, 2 nm to 13 nm, 3 nm to 10 nm, 3.5 nm to 8.0 nm, 4 nm to 6.5 nm, 4 nm to 6.0 nm, or 4 nm to 5.0 nm.

[0036] The number-average particle size of the chalcogenide perovskite particles described above is measured by directly measuring the particle size on the TEM image obtained by microscopy. Although not particularly limited, when measuring particle size, it is preferable to consider the particle image obtained by TEM observation as a projection of a spherical or polygonal object and perform elliptical fitting. When measuring particle size, for example, three or more TEM images may be selected, and the particle size of all measurable nanoparticles contained in them (i.e., all particles except those whose image is cut off at the edge of the image) may be measured. Then, it is preferable to derive the number-average particle size by calculating the geometric mean of the major and minor axes of the elliptical fitting for each particle and then calculating their arithmetic mean.

[0037] In this embodiment, the number-average particle size is calculated by the method described below. The particle image obtained by TEM observation is considered as a projection of a spherical or polygonal object, and an elliptical fitting is performed. The number-average particle size is calculated by selecting three or more TEM images and measuring the particle size of all measurable nanoparticles contained in them (i.e., all particles except those whose images are cut off at the edges of the image). Here, the observation range is 180 nm vertically and horizontally, and observation is performed in multiple fields of view until the particle size of 100 or more particles is measured. The number-average particle size value is derived by calculating the geometric mean of the major and minor axes when the elliptical fitting is performed on each particle, and then calculating their arithmetic mean. At the same time, the variance value is calculated and used as the particle size distribution (an indicator of the magnitude of particle size variation). More details are explained in the Examples section.

[0038] When the number-average particle size of chalcogenide perovskite particles is approximately 15 nm or less, the chalcogenide perovskite particles are more likely to exhibit the following effects (a) and (b).

[0039] (a) Firstly, the chalcogenide perovskite particles of this embodiment can have their band gap controlled by the quantum size effect.

[0040] Figure 1 is a graph showing an example of the relationship between the excitation energy and particle size of semiconductor particles. The vertical axis of Figure 1 represents the band gap (eV), and the horizontal axis represents the particle diameter (nm). Generally, when the particle size of semiconductor particles decreases to about 15 nm, the band structure (energy levels) of the particle becomes discrete, and the value of the optical band gap changes depending on the particle size (quantum size effect). In this case, the value of the band gap increases gradually as the particle size decreases, and then increases sharply when the particle size becomes smaller than a certain particle size. In Figure 1, the particle size at the boundary where the quantum size effect occurs is shown by a dashed line. From Figure 1, it can be seen that when the number-average particle size of chalcogenide perovskite particles is 10 nm or less, the value of the band gap increases sharply.

[0041] The chalcogenide perovskite particles of this embodiment have a number-average particle size of approximately 15 nm or less, and exhibit a high band gap due to the quantum size effect compared to particles with a larger particle size. Furthermore, by controlling the particle size of the chalcogenide perovskite particles within an appropriate range, it is possible to change the band gap obtained by the quantum size effect to a desired value. For example, when applying chalcogenide perovskite particles to light-emitting materials or power-generating materials, chalcogenide perovskite particles exhibiting a desired band gap can be obtained by controlling the particle size, and it is possible to control them to exhibit light absorption characteristics and emission characteristics (emission wavelength) suitable for each application.

[0042] (b) Secondly, the chalcogenide perovskite particles of this embodiment can improve luminescence efficiency through a carrier confinement effect.

[0043] When the particle size of semiconductor particles becomes small enough to be on the order of nanometers, excited carriers (electrons and holes) become spatially confined, making it difficult for them to dissipate (carrier confinement effect).

[0044] The chalcogenide perovskite particles of this embodiment have a number-average particle size of approximately 15 nm or less, which significantly narrows the range over which excited and confined carriers can move. Consequently, the probability of carrier recombination within the particles is improved. For example, when the chalcogenide perovskite particles of this embodiment are applied to a light-emitting material, excellent luminescence properties can be obtained by improving the luminescence efficiency due to the carrier confinement effect.

[0045] <Product Forms and Application Examples of Chalcogenide Perovskite Particles> Examples of product forms for the chalcogenide perovskite particles in this embodiment include powder, dispersion, thin film, sheet, etc.

[0046] (Powder) In this specification, a powder containing chalcogenide perovskite particles means a mixture or aggregation of chalcogenide perovskite particles (or chalcogenide perovskite composites) in a solvent-free state. A powder containing chalcogenide perovskite particles may contain other materials as additives for the purpose of improving various properties such as luminescence properties, dispersibility in other materials, and film-forming properties when used as a composition as described later. In other words, a powder containing chalcogenide perovskite particles means an aggregate of chalcogenide perovskite particles (or chalcogenide perovskite composites), or a mixture of these and additives.

[0047] The applications of the powder containing chalcogenide perovskite particles are not particularly limited. For example, the powder may be dispersed in a liquid dispersion medium and used as a liquid composition (dispersion), or it may be dispersed in a resin or a solid medium (solid dispersion medium) and used as a solid composition. Alternatively, the powder may be sintered and used as a sintered body. A sintered body of powder containing chalcogenide perovskite particles can be used, for example, as a sputtering target. The powder may also be used in its powder form. Powder containing chalcogenide perovskite particles can be used, for example, as a vapor deposition source when performing vapor deposition.

[0048] (Dispersion) In this specification, a dispersion containing chalcogenide perovskite particles means a dispersion in which chalcogenide perovskite particles (or chalcogenide perovskite composites) are dispersed in a liquid dispersion medium. Here, "dispersed chalcogenide perovskite particles" means a state in which the chalcogenide perovskite particles are suspended or floating in the liquid dispersion medium, and some of the chalcogenide perovskite particles may settle in the dispersion.

[0049] Dispersions containing chalcogenide perovskite particles may also contain additives such as acids, bases, and binder materials in addition to chalcogenide perovskite, for the purpose of improving various properties of chalcogenide perovskite, such as dispersibility, luminescence properties, and film-forming properties. The size of the chalcogenide perovskite particles (or chalcogenide perovskite composites) contained in the above dispersion is not particularly limited.

[0050] The type of liquid dispersion medium used in the above dispersion is not particularly limited, but examples include water, esters such as methyl formate, ethyl formate, propyl formate, pentyl formate, methyl acetate, ethyl acetate, and pentyl acetate; ketones such as γ-butyrolactone, acetone, dimethyl ketone, diisobutyl ketone, cyclopentanone, cyclohexanone, and methylcyclohexanone; ethers such as diethyl ether, methyl-tert-butyl ether, diisopropyl ether, dimethoxymethane, dimethoxyethane, 1,4-dioxane, 1,3-dioxolane, 4-methyldioxolane, tetrahydrofuran, methyltetrahydrofuran, anisole, and phenethole; methanol, ethanol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, tert-butanol, 1-pentanol, 2-methyl-2-butanol, methoxypropanol, diacetone alcohol, cyclohexanol, and 2-fluoroethanol. Examples include alcohols such as 2,2,2-trifluoroethanol and 2,2,3,3-tetrafluoro-1-propanol; glycol ethers such as ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, ethylene glycol monoethyl ether acetate, and triethylene glycol dimethyl ether; organic solvents having amide groups such as N-methyl-2-pyrrolidone, N,N-dimethylformamide, acetamide, and N,N-dimethylacetamide; organic solvents having nitrile groups such as acetonitrile, isobutyronitrile, propionitrile, and methoxyacetonitrile; organic solvents having carbonate groups such as ethylene carbonate and propylene carbonate; organic solvents having halogenated hydrocarbon groups such as methylene chloride and chloroform; organic solvents having hydrocarbon groups such as n-pentane, cyclohexane, n-hexane, benzene, toluene, and xylene; and dimethyl sulfoxide. Note that one type of liquid dispersion medium may be used alone in the above dispersion, or two or more types may be used in combination.

[0051] The uses of the dispersion described above are not particularly limited. For example, it may be used as a film-forming material when forming films using solution-based film-forming methods such as coating, spraying, or doctor blade methods, or it may be used as a composite composition by combining a dispersion containing chalcogenide perovskite particles with a solid dispersion medium.

[0052] (Thin film) In this specification, a thin film containing chalcogenide perovskite particles means a film in which chalcogenide perovskite particles (or chalcogenide perovskite composites) are aggregated in a planar manner.

[0053] Thin films containing chalcogenide perovskite particles may also contain other materials as additives to improve various properties such as the dispersibility and luminescence characteristics of the chalcogenide perovskite particles within the film. The size of the chalcogenide perovskite particles (or chalcogenide perovskite composite) contained in the thin film is not particularly limited.

[0054] The method for producing the thin film described above is not particularly limited. For example, a dispersion of chalcogenide perovskite particles in a liquid dispersion medium, or a precursor material of chalcogenide perovskite particles (for example, a dispersion of a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid dispersed in a dispersion medium) may be used to form a thin film by a solution deposition method such as coating, spraying, doctor blade, or inkjet, and then, if necessary, drying, calcination, or other treatments may be performed to form a thin film containing chalcogenide perovskite particles, thereby obtaining chalcogenide perovskite particles.

[0055] For example, when a precursor material (a dispersion in which a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid are dispersed in a dispersion medium) is used as the film-forming material and a film is formed by a solution film-forming method such as coating, the complex having the first metal atom and the complex having the second metal atom react in the film when the coating is heated at a predetermined temperature. This results in a thin film containing chalcogenide perovskite particles. The method for producing the thin film is not limited to the film-forming method described above. For example, a thin film containing chalcogenide perovskite particles (e.g., a powder containing chalcogenide perovskite particles or a chalcogenide perovskite composite, a molded body of the powder, or a sintered body of the powder, etc.) or a precursor material of chalcogenide perovskite particles may be formed using a vacuum process such as sputtering or vacuum deposition, and then, if necessary, fired or otherwise treated to form a thin film containing chalcogenide perovskite particles. Furthermore, when heat, calcination, or other treatments are performed during the formation of a thin film, the chalcogenide perovskite particles in the final thin film do not necessarily have to maintain the particle shape before the heat treatment or other treatments.

[0056] (Sheet) In this specification, a sheet containing chalcogenide perovskite particles refers to a composition formed in a planar shape from which chalcogenide perovskite particles (or chalcogenide perovskite composites) are dispersed in a solid dispersion medium. A sheet containing chalcogenide perovskite particles may also contain additives other than chalcogenide perovskite, such as silica nanoparticles, acids, bases, or binder materials, for the purpose of improving various properties such as the dispersibility and luminescence characteristics of the chalcogenide perovskite particles. The size of the chalcogenide perovskite particles (or chalcogenide perovskite composites) contained in the above sheet is not particularly limited.

[0057] Any known polymer material used for this type of purpose can be arbitrarily applied as the solid dispersion medium for the sheet described above. The polymer material used as the solid dispersion medium for the sheet is preferably one that exhibits a translucent or semi-transparent appearance when formed into a sheet.

[0058] Furthermore, the solid dispersion medium used in the above-mentioned sheet is not particularly limited, but examples include polyvinyl butyral, polyvinyl acetate, silicone and silicone derivatives, ionomers, polyethylene, polyvinyl chloride, polyvinylidene chloride, polyvinyl alcohol, polypropylene, polyester, polycarbonate, polystyrene, polyacrylonitrile, ethylene vinyl acetate copolymer, ethylene-vinyl alcohol copolymer, ethylene-methacrylic acid copolymer film, nylon, etc. Examples of silicone derivatives include polyphenylmethylsiloxane, polyphenylalkylsiloxane, polydiphenylsiloxane, polydialkylsiloxane, fluorinated silicones, and vinyl and hydride-substituted silicones.

[0059] Furthermore, the method for producing the above-mentioned sheet is not particularly limited. For example, a sheet containing chalcogenide perovskite particles may be produced by kneading a powder containing the above-mentioned chalcogenide perovskite particles with a solid dispersion medium and then stretching the mixture. Alternatively, the above-mentioned sheet may be produced by applying a dispersion, which is a mixture of a liquid composition containing chalcogenide perovskite particles and various additives, with a solid dispersion medium or a precursor of a solid dispersion medium, onto a sheet, and then drying it as necessary.

[0060] (Devices) The applications of the above chalcogenide perovskite particles, powders, dispersions, thin films, and sheets are not particularly limited. For example, the above chalcogenide perovskite particles, powders, dispersions, thin films, and sheets are envisioned for application in the down-conversion of ultraviolet light or blue light in various devices. Furthermore, the above chalcogenide perovskite particles, powders, dispersions, thin films, and sheets can be suitably used in the manufacture of various devices such as light-emitting devices like LEDs and organic ELs, display devices including such light-emitting devices, lighting devices including such light-emitting devices, image sensors, photoelectric conversion devices, and bioluminescent labels.

[0061] <Method for producing chalcogenide perovskite particles> Next, the method for producing the chalcogenide perovskite particles of this embodiment will be described. The chalcogenide perovskite particles of this embodiment can be produced by reacting a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid in a solvent in the liquid phase.

[0062] From the viewpoint of suppressing side reactions in the liquid phase and exhibiting a crystal structure similar to that of solid-phase synthesis, it is preferable that the complex having the first metal atom and the complex having the second metal atom each have ligands that do not contain oxygen atoms (O) and halogen atoms (X) as coordinating atoms. Here, examples of halogen atoms (X) include fluorine atoms (F), chlorine atoms (Cl), bromine atoms (Br), iodine atoms (I), and the like.

[0063] The ligands of the complex having the first metal atom and the complex having the second metal atom are not particularly limited. For example, ligands can be selected from the group consisting of nitrogen (N), sulfur (S), selenium (Se), tellurium (Te), carbon (C), and phosphorus (P). The ligands of the complex having the first metal atom and the ligands of the complex having the second metal atom may be of the same type or of different types.

[0064] Ligands that coordinate with a nitrogen atom include alkylamines (NR) such as amines, dimethylamine, diethylamine, and methylethylamine. ２ ); arylamines such as phenylamine (NHAr); trialkylsilylamines such as silylamine and trimethylsilylamine (N(SiR ３ ) ２ Examples include nitrogen-containing aromatic rings such as pyrazoles.

[0065] Ligands that coordinate with a sulfur atom include dithiocarbamates (S ２ CNR ２ ), xanthan (S ２ COR), trithiocarbamate (S ２ CSR), dithioester (S ２ Examples include CR, thiolate (SR), etc.

[0066] Examples of ligands coordinated by selenium atoms or tellurium atoms include compounds in which some or all of the sulfur atoms of the ligands coordinated by the above sulfur atoms are replaced by selenium atoms or tellurium atoms.

[0067] The complex having the first metal atom and the complex having the second metal atom may be a single compound (polynuclear complex). The single compound (polynuclear complex) refers to a compound having both the first metal atom and the second metal atom as the central metal ions in one complex. Preferably, the first metal atom and the second metal atom may be bonded via a ligand coordinated by a sulfur atom, a selenium atom, or a tellurium atom. Examples of the polynuclear complex in which the ligand is coordinated by a sulfur atom include heterobimetal thiolate, heterobimetal sulfide, etc. In these polynuclear complexes, the first metal atom and the second metal atom are bonded via thiolate or sulfide (ligand coordinated by a sulfur atom) as a ligand. Examples of the polynuclear complex in which the ligand is coordinated by a selenium atom or a tellurium atom include those in which some or all of the sulfur atoms in the polynuclear complex in which the ligand is coordinated by a sulfur atom are replaced by selenium atoms or tellurium atoms.

[0068] Examples of ligands coordinated by carbon atoms include alkanes such as methyl and ethyl; unsaturated hydrocarbon rings such as cyclopentadiene, cyclooctadiene, and indene, or groups derived from benzyl groups and other unsaturated hydrocarbon rings described above; cyanide (CN), etc.

[0069] Examples of ligands coordinated by phosphorus atoms include trialkylphosphines (PR ３ ), such as trioctylphosphine and tricyclohexylphosphine; triarylphosphines (PAr ３ ), such as triphenylphosphine and tri(o-tolyl)phosphine; diphosphines (R ２ P-(CH ２ )) ｍ -PR ２ ), etc.

[0070] In addition, the ligand may be a derivative of the above-described ligand.

[0071] In each of the above general formulas, R is a hydrogen atom, a saturated hydrocarbon group having 1 to 20 carbon atoms, or an unsaturated hydrocarbon. When one ligand contains two or more Rs, the Rs may be the same or different from each other. Ar is an aryl group having 6 to 20 carbon atoms which may have substituents, such as a phenyl group, a naphthyl group, an anthracenyl group, etc. Examples of the substituent include an alkyl group having 1 to 10 carbon atoms. When one ligand contains two or more Ars, the Ars may be the same or different from each other. m is an integer of 1 to 10.

[0072] Among the above-mentioned ligands, a ligand coordinated by a nitrogen atom or a ligand coordinated by a sulfur atom is preferable. Further, a ligand having a structure selected from the group consisting of the following formulas (1) to (7) is preferable. S ２ CNR ａ ２ (1) S ２ COR (2) S ２ CSR ａ (3) S ２ CR ａ (4) SR ａ (5) NR ａ ２ (6) N(SiR ａ ３ ) ２ (7) (In the formula, R ａ is a hydrogen atom, a saturated hydrocarbon group having 1 to 20 carbon atoms, or an unsaturated hydrocarbon group having 1 to 20 carbon atoms. When one ligand has a plurality of R ａ , the plurality of R ａ may be the same or different from each other.)

[0073] Examples of the saturated hydrocarbon group and unsaturated hydrocarbon mentioned above include C1-C20 alkyl groups, C3-C20 cycloalkyl groups, C2-C20 alkenyl groups, C2-C20 alkynyl groups, C3-C20 cycloalkenyl groups, C3-C20 cycloalkynyl groups, C3-C20 cycloalkadienyl groups, and C6-C20 aryl groups. The saturated hydrocarbon group and unsaturated hydrocarbon may have substituents. Examples of substituents include C1-C10 alkyl groups.

[0074] For example, the ligand is preferably a compound represented by formula (1) above. Also, R in formula (1) ａ It is preferably an alkyl group having 1 to 10 carbon atoms, and more preferably an alkyl group having 2 to 6 carbon atoms.

[0075] The ligands used in this embodiment can be synthesized according to conventional methods. Alternatively, commercially available compounds may be used.

[0076] The metal atom of the complex having the first metal atom is a metal atom selected from alkaline earth metal elements, and the metal atom of the complex having the second metal atom is a metal atom selected from transition metal elements. For example, the metal atom of the complex having the first metal atom includes at least one of Sr and Ba, and the metal atom of the complex having the second metal atom includes at least one of Zr and Hf. At least one of the metal atoms of the complex having the first metal atom and the metal atom of the complex having the second metal atom may further include at least one selected from Ti, Ca, and Mg. For example, the metal atom of the complex having the first metal atom may include at least one of Sr and Ba, as well as at least one of Ti, Ca, and Mg. Also, the metal atom of the complex having the second metal atom may include at least one of Zr and Hf, as well as Ti. By including Ti in the chalcogenide perovskite, it becomes possible to control the band gap of the chalcogenide perovskite. Furthermore, when Ti is included in the chalcogenide perovskite, the chalcogenide perovskite is (Sr x Ba 1-x ) (Zry Ti ｙ’ HF 1-y-y’ ) (S z See 1-z ) 3 or (Sr x’ Ba 1-x’ ) 2 (Sr x Ba 1-x ) n-1 (Zr y Ti ｙ’ HF 1-y-y’ ) n (S z See 1-z ) 3n+1 It can also be expressed as (where x, x', y, y', and z are values ​​between 0 and 1, and n is a positive integer).

[0077] The complexes having the first metal atom and the complex having the second metal atom can be synthesized by selecting the starting components according to the type of metal atom and ligand they each possess, using known methods. Alternatively, commercially available metal complexes may be used.

[0078] When a complex having a first metal atom and a complex having a second metal atom, each possessing the above-mentioned ligand, are reacted in the liquid phase, a Lewis acid may be added to improve the decomposition reaction rate. In one embodiment, a Lewis acid may be added to a dithiocarbamate complex to improve the decomposition reaction rate. As a result, the variation in particle size of each particle produced in liquid-phase synthesis can be reduced. Furthermore, by improving the decomposition reaction rate through the addition of a Lewis acid, the particle size of the chalcogenide perovskite particles produced in liquid-phase synthesis can also be reduced.

[0079] Generally, the formation of semiconductor nanoparticles in solution involves two stages: nucleation and nucleation growth. Nucleation is a reaction that occurs when clusters of atoms that make up the nanoparticles reach a concentration exceeding saturation (supersaturation) in the solution. Rapid decomposition of the raw materials rapidly generates the aforementioned atomic clusters, increasing the degree of supersaturation and allowing nucleation to occur in a relatively short time. It is hypothesized that a shorter nucleation time will result in less variation in the particle size of the resulting nanoparticles. Lewis acids are thought to reduce the variation in the particle size of the resulting nanoparticles by promoting the decomposition of the raw materials and increasing the degree of supersaturation of the atomic clusters. Furthermore, a shorter nucleation time may result in smaller particle sizes for the resulting nanoparticles. Lewis acids are thought to reduce the particle size of the resulting nanoparticles by promoting the decomposition of the raw materials and increasing the supersaturation of the atomic clusters. As an example, it is thought that the variation in particle size of chalcogenide perovskite particles in liquid-phase synthesis can be controlled to reduce variation by adding a Lewis acid to the complex. In the above, it is thought that the variation in particle size of chalcogenide perovskite particles tends to decrease as the amount of Lewis acid added increases.

[0080] Furthermore, the addition of Lewis acids improves the degree of supersaturation of atomic clusters compared to the case without Lewis acids. As a result, it may be possible to suppress variations in the particle size of the resulting nanoparticles to a similar degree even at lower reaction temperatures compared to the case without Lewis acids.

[0081] The above list of Lewis acids is not limited to any specific type, but examples include metal chlorides, metal fluorides, metal bromides, and metal iodides. Examples of metal chlorides include aluminum chloride (AlCl). ３ ) and zirconium chloride (ZrCl ４Examples include the following. Furthermore, from the viewpoint of suppressing variations in the particle size of chalcogenide perovskite particles, the amount of Lewis acid added to the complex is preferably more than 0.5 mol% (for example, 0.01 mmol when the total amount of Ba and Zr is 2 mmol), more preferably more than 2.5 mol%, even more preferably 3.75 mol% or more, and particularly preferably 5 mol% or more, relative to the total amount of metal precursor complexes used as raw materials.

[0082] On the other hand, from the viewpoint of suppressing the generation of halogen-derived impurities in chalcogenide perovskite particles, it is preferable that the amount of Lewis acid added to the complex be 5 mol% or less relative to the total amount of metal precursor complexes used as raw materials. However, from the viewpoint of controlling the variation in particle size of chalcogenide perovskite particles while suppressing the influence of the above impurities to a practically acceptable range, it is preferable that the amount of Lewis acid added to the complex be 15 mol% or less, more preferably 10 mol% or less, and even more preferably 8 mol% or less, relative to the total amount of metal precursor complexes used as raw materials. Although not particularly limited, the amount of Lewis acid added to the complex may be 0.5 mol% to 15 mol%, 2.5 mol% to 10 mol%, 3.75 mol% to 8 mol%, or 3.75 mol% to 5 mol%, relative to the total amount of metal precursor complexes used as raw materials.

[0083] While not particularly limited, from the viewpoint of obtaining stable characteristics with respect to emission wavelength and emission width at half maximum (color purity), the particle size distribution of the chalcogenide perovskite particles is, for example, within ±8.0 nm, preferably within ±5.0 nm, more preferably within ±3.0 nm, even more preferably within ±2.5 nm, even more preferably within ±2.0 nm, particularly preferably within ±1.0 nm, and particularly more preferably within ±0.85 nm.

[0084] Furthermore, the solvent used in the liquid-phase synthesis of this embodiment is determined by the solubility of the complex having the first metal atom and the complex having the second metal atom, and H ２From the viewpoint of sulfur generation efficiency and other factors, appropriate solvents can be selected. Examples of solvents include saturated aliphatic hydrocarbons, unsaturated aliphatic hydrocarbons, aromatic hydrocarbons, nitrogen-containing heterocyclic compounds, alcohols, aldehydes, carboxylic acids, primary amines, secondary amines, tertiary amines, phosphine compounds, and thiols. As for the solvent, considering that the liquid phase may be heated to a high temperature of, for example, 300°C or higher in the liquid phase synthesis step described later, it is preferable to use a solvent with a higher boiling point. For example, octadecene (ODE) exhibits a high boiling point and can therefore be suitably used as a solvent.

[0085] In this embodiment, for example, in addition to the complex having the first metal atom and the complex having the second metal atom described above, an amine compound may be further added to the liquid phase. The amine compound functions as a reaction initiator. The amine compound may also be used as the solvent described above. Preferably, the amine compound does not contain oxygen atoms (O) or halogen atoms (X). Examples include alkylamines having one alkyl group, such as oleylamine, hexadecylamine, and octadecylamine; dialkylamines having two alkyl groups with 1 to 30 carbon atoms; and trialkylamines having three alkyl groups with 1 to 30 carbon atoms (e.g., trioctylamine). From the viewpoint of fully exhibiting its function as a reaction initiator between the ligand and the metal component, it is preferable to add an amount of the amine compound equal to or greater than the total amount of ligands contained in the complex having the first metal atom and the complex having the second metal atom added to the liquid phase. Furthermore, the amine compound may be added to the liquid phase in excess of the amount mentioned above (equal to the total amount of ligands) from the viewpoint of exhibiting its function as a surfactant that adheres to the particle surface of the chalcogenide perovskite ultimately obtained. Although not particularly limited, it is more preferable that the amine compound be added in an amount of substance that is preferably 4 to 48 times, more preferably 8 to 36 times, and even more preferably 12 to 24 times, the total amount (mol) of ligands contained in the compound having the first metal atom and the compound having the second metal atom added to the liquid phase. The more the amount of amine compound added, the better the dispersibility can be. On the other hand, by not adding too much amine compound, the generation of impurities can be suppressed.

[0086] Furthermore, in addition to the complex having the first metal atom and the complex having the second metal atom, a chalcogen compound can be added to the liquid phase. For example, if the ligands of the complex having the first metal atom and the complex having the second metal atom do not contain chalcogen elements such as sulfur (S), or if the chalcogen elements contained in the ligands are insufficient, the composition of the target chalcogenide perovskite can be adjusted by adding an appropriate amount of chalcogen compound to the liquid phase.

[0087] Preferably, the chalcogen compound used does not contain oxygen atoms (O) or halogen atoms (X). For example, sulfur or carbon disulfide (CS ２ ), hydrogen sulfide (H ２ Sulfides such as S, selenium or selenides, tellurium or tellurides, hexanethiol, octanthiol, decanethiol, dodecanethiol (n-dodecanethiol, t-dodecanethiol), hexadecanethiol, mercaptopropylsilane, dialkylthiourea (S=C(NR ２ ) ２ Examples include sulfur-trioctylphosphine (trioctylphosphine sulfide; S-TOP), sulfur-tributylphosphine (S-TBP), sulfur-triphenylphosphine (S-TPP), sulfur-trioctylamine (S-TOA), bis(trimethylsilyl) sulfide, ammonium sulfide, sodium sulfide, selenium-trioctylphosphine (Se-TOP), selenium-tributylphosphine (Se-TBP), and selenium-triphenylphosphine. Among these, dialkylthiourea (S=C(NR ２ Thioureas such as ) are, for example, carbon disulfide (CS ２ Because it has a higher boiling point than ), it can be suitably used as a chalcogen compound.

[0088] In the manufacturing method of this embodiment, the complex having the first metal atom and the complex having the second metal atom described above are reacted in the liquid phase with a Lewis acid and, if necessary, a chalcogen compound and an amine compound, and the procedure is not particularly limited. The manufacturing method of this embodiment can be carried out by known methods such as the hot injection method, the heat-up method and the flow synthesis method. The mixing ratio of the complex having the first metal atom and the complex having the second metal atom can be adjusted according to the composition of the target chalcogenide perovskite particles. Although not particularly limited, it is preferable that the mixing ratio of the compound having the first metal atom and the compound having the second metal atom be determined such that the ratio of the amount of substance of the first metal atom to the amount of substance of the second metal atom is 0.8 times or more and 1.2 times or less, preferably 0.9 times or more and 1.1 times or less, and more preferably 1.0 times, the atomic ratio in the composition of the chalcogenide perovskite-type compound to be manufactured.

[0089] In the manufacturing method of this embodiment, when the raw material components include a complex having at least a first metal atom, a complex having a second metal atom, a Lewis acid, and a solvent, a first raw material is prepared, which includes at least the solvent from the said raw material components, and a second raw material is prepared, which includes at least the remaining raw material components not included in the first raw material. Then, the reaction is brought about by adding the second raw material to the first raw material. In this embodiment, it is preferable to add the second raw material to the first raw material after preheating at least one of the first and second raw materials. Alternatively, the second raw material may be added to the first raw material and then heated to bring about the reaction.

[0090] The method for producing chalcogenide perovskite particles in this embodiment will be described below, using the hot injection method as an example. First, the first raw material is preheated. The heating rate is not particularly limited, but for example, it is heated at a heating rate of 1 to 30°C / min, typically 1 to 10°C / min. The temperature of the first raw material after heating is not particularly limited, but for example, it may be room temperature to 450°C, or 120 to 360°C. Next, the second raw material is added to the first raw material to cause a reaction between the first metal atom-containing complex, the second metal atom-containing complex, and the Lewis acid. The second raw material may also be preheated in the same way as the first raw material. The rate of addition of the second raw material is not particularly limited, but it is preferable to adjust it considering the decrease in liquid phase temperature due to the addition of the second raw material. The liquid phase temperature after mixing is preferably room temperature to 450°C, more preferably 120 to 360°C.

[0091] For example, either the complex having the first metal atom or the complex having the second metal atom may have a ligand represented by the above formula (1) (dithiocarbamate (S ２ CNR ２ If the ligand is present, and the liquid phase temperature is 120°C or higher, the metal complex having the ligand can be initiated by the amine compound, allowing the reaction between the complex having the first metal atom and the complex having the second metal atom to proceed smoothly. Although the reaction can be initiated without using an amine compound, in this case, it is preferable to raise the liquid phase temperature above 120°C. Furthermore, by keeping the liquid phase temperature below 360°C, the vaporization of commonly used solvents is suppressed, enabling stable liquid-phase synthesis.

[0092] In this embodiment, by preheating the first raw material and then adding the second raw material to it, all the components contributing to the synthesis of chalcogenide perovskite (solvent, complex having a first metal atom, complex having a second metal atom, and Lewis acid) are present in the liquid phase at the same time, causing them all to reach a high temperature simultaneously. This allows the reaction start times of the complex having the first metal atom and the complex having the second metal atom to be approximately simultaneous. As a result, the reactions of the complex having the first metal atom and the complex having the second metal atom proceed in a balanced manner, enabling the synthesis of chalcogenide perovskite with high purity.

[0093] In this embodiment, when the above-mentioned amine compound is added to the liquid phase as a reaction initiator, the raw material components include a solvent, a complex having a first metal atom, a complex having a second metal atom, a Lewis acid, and an amine compound. The combination of the first raw material component and the second raw material component is not particularly limited.

[0094] For example, the first raw material may be a solvent only, and the second raw material may be a mixture of a complex having a first metal atom, a complex having a second metal atom, a Lewis acid, and an amine compound. Alternatively, the first raw material may be a mixture of a solvent and an amine compound, and the second raw material may be a mixture of a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid. Alternatively, the first raw material may be a mixture of either the complex having a first metal atom or the complex having a second metal atom and a solvent, and the second raw material may be a mixture of the other of the complex having a first metal atom or the complex having a second metal atom, a Lewis acid, and an amine compound.

[0095] In this embodiment, when the chalcogen compound described above is added to the liquid phase, the raw material components include a solvent, a complex having a first metal atom, a complex having a second metal atom, a Lewis acid, and a chalcogen compound. The combination of the first raw material component and the second raw material component is not particularly limited.

[0096] For example, the first raw material may be a solvent only, and the second raw material may be a mixture of a complex having a first metal atom, a complex having a second metal atom, a Lewis acid, and a chalcogen compound. Alternatively, the first raw material may be a mixture of a solvent and a chalcogen compound, and the second raw material may be a mixture of a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid. Alternatively, the first raw material may be a mixture of either the complex having a first metal atom or the complex having a second metal atom and a solvent, and the second raw material may be a mixture of the other of the complex having a first metal atom or the complex having a second metal atom, a Lewis acid, and a chalcogen compound.

[0097] In this embodiment, the liquid phase obtained by adding the second raw material to the first raw material is heated and stirred for, for example, 0 to 24 hours while maintaining a temperature preferably between room temperature and 450°C, more preferably between 120 and 360°C. After stirring is complete, the precipitate formed in the liquid phase is isolated by a known method to obtain the target product, chalcogenide perovskite particles. The reasons why temperatures above 120°C and below 360°C are preferable are the same as those explained when using the hot injection method.

[0098] In the series of liquid-phase synthesis described above, it is preferable to carry out the synthesis in an environment where components such as water and oxygen are removed as much as possible. For example, the series of liquid-phase synthesis described above is preferably carried out in an inert atmosphere filled with nitrogen or argon.

[0099] The method for producing chalcogenide perovskite particles in this embodiment may be, for example, by the flow synthesis method described below. First, a complex having a first metal atom, a complex having a second metal atom, a Lewis acid, and at least one of a chalcogen compound and an amine compound are each dissolved in a solvent and then passed through separately as raw material flows.

[0100] Next, the reaction is initiated by combining all the raw material flows simultaneously or in stages. At this time, it is preferable to preheat at least one of the raw material flows before combining them. The raw material flow that is preheated is preferably the flow with the highest flow rate. Furthermore, since the reaction field is small in flow synthesis, the temperature can be raised instantaneously even if heating is done immediately after the combination of each raw material flow, and the reaction start time of the complex having the first metal atom and the reaction start time of the complex having the second metal atom can be made approximately simultaneous. The heating rate and the temperature of the components after heating are the same as in the hot injection method.

[0101] <Description of Examples> Examples and comparative examples of the present invention will be described below. In the description of the examples, chalcogenide perovskite particles may be referred to as first semiconductor nanoparticles, and chalcogenide perovskite composites as second semiconductor nanoparticles. First, the preparation steps for each example and comparative example will be described.

[0102] (Barium bis-diisobutyldithiocarbamate (Ba(DiBuDTC)) ２ (Synthesis) In a nitrogen glove box (moisture content 1 ppm or less), a stirring bar and barium hydroxide (Ba(OH)) are placed in a 500 mL three-necked flask. ２10.3 g of (anhydrous, Merck) was placed in the flask, which was then sealed with a rubber stopper and a glass stopper and removed from the glove box. A pressure-maintaining dropping funnel was attached to the flask, and the inside was purged with argon. Ultrapure water (18.2 MΩcm, Merck Millipore, Integral-3) immediately after collection was quickly added and stirred with a magnetic stirrer. 132 mmol of diisobutylamine (TCI), which had been stored in the glove box, was placed in the dropping funnel, and the lid was closed and the solution was slowly added dropwise over 10 minutes. The solution was heated to 40°C using a heat gun to obtain a gray suspension. Subsequently, 132 mmol of carbon disulfide (Fujifilm Wako) was added to the dropping funnel, and the lid was closed and the solution was added dropwise over 20 minutes. The clarity of the solution initially increased, but then it began to become cloudy. The solution was stirred at room temperature for 5 hours. 300 mL of ultrapure water was added to the obtained suspension, and the solution was heated to 50°C in a water bath, at which point the amount of precipitate decreased. A layer of Celite (manufactured by Fujifilm Wako) approximately 5 mm thick was spread on filter paper (ADVANTEC, #131), and the precipitate was removed by suction filtration to obtain a clear solution. Ultrapure water was then poured over the Celite to wash the precipitate. The filtrate was concentrated using a rotary evaporator (EYELA, N-1115) to obtain colorless crystals. After cooling in a flask with ice, the precipitate was filtered off by suction filtration. Vacuum drying was performed overnight at 40°C, and Ba (DiBuDTC) was added. ２ White crystals were obtained.

[0103] (Zirconium tetrakisdiisobutyldithiocarbamate (Zr(DiBuDTC)) ４ (Synthesis) In a nitrogen glove box (moisture content 1 ppm or less), a stirring bar and zirconium chloride (ZrCl) were added to a 300 mL three-necked flask. ４) was added, the flask was sealed with a rubber stopper and a glass stopper, and then removed from the glove box. A pressure-maintaining dropping funnel was attached to the flask, the inside was purged with argon, and then the flask was cooled with ice. 180 mL of tetrahydrofuran (THF) was added using the dropping funnel while stirring with a magnetic stirrer. Next, 500 mmol of diisobutylamine (TCI), which had been stored in the glove box, was placed in the dropping funnel, the lid was closed, and it was slowly added dropwise over 10 minutes, after which stirring was continued for another 10 minutes. Next, 250 mmol of carbon disulfide (Fujifilm Wako) was added to the dropping funnel and added dropwise to the reaction solution over 20 minutes. After stirring at room temperature for 5 hours, an orange suspension was obtained. A Celite bed was prepared by spreading Celite (Fujifilm Wako) to a thickness of approximately 5 mm on filter paper (ADVANTEC, #131), and the precipitate (isobutylammonium chloride) was removed. A yellow, transparent THF solution was concentrated using a rotary evaporator to a total volume of 30 mL. While stirring, hexane was gradually added to this solution, totaling 300 mL, to obtain a white precipitate. The solid was filtered off by suction filtration and washed with hexane. The obtained solid was white or pale pink. The solid was dispersed in 300 mL of ethanol, stirred for several minutes, then recovered again by suction filtration and washed with ethanol. The obtained white solid was vacuum-dried overnight at 40°C, and Zr(DiBuDTC) was extracted. ４ I obtained it.

[0104] (Setup of Nanoparticle Synthesis Reactor) A mantle heater was set at the bottom of a 50 mL two-neck flask and placed on top of a magnetic stirrer. A thyristor voltage regulator was connected to the output terminal of a PID-controlled temperature controller, and the voltage was adjusted to apply 40 V to the mantle heater with a maximum output of 50 W. A stainless steel K-type thermocouple was connected to this temperature controller and inserted into the two-neck flask to measure the liquid temperature. The PID parameters of the temperature controller were optimized so that the liquid temperature in the reaction vessel quickly reached the set temperature within the range of 100 to 350 °C.

[0105] (Example 1) In Example 1, a solution containing the first semiconductor nanoparticles and a dispersion of the first semiconductor nanoparticles were obtained by the following method. First, 1 mmol of barium bis-diisobutyldithiocarbamate (Ba(DiBuDTC)) ２ ), 1 mmol of zirconium tetrakisdiisobutyldithiocarbamate (Zr(DiBuDTC) ４ ), 6 mL of 1-octadecene (ODE) was placed in a 50 mL two-necked flask. This mixture is called mixture A.

[0106] Mixture A was heated to 80°C under vacuum for 5 minutes while being stirred with a magnetic stirrer. After degassing and dehydrating the reaction vessel, argon was introduced into the reaction vessel and heated to 300°C. In a separate container, 0.1 mmol of aluminum chloride and 4.8 mL of oleylamine (OLA) solution were added to prepare a solution. This is referred to as mixture B.

[0107] Mixture B was placed in a gastight syringe and injected all at once into mixture A, which was being heated and stirred. After injection, the mixture was heated at 300°C for 30 minutes to obtain the solution containing the first semiconductor nanoparticles of Example 1.

[0108] Subsequently, to isolate the first semiconductor nanoparticles, the solution containing the first semiconductor nanoparticles was transferred to a 50 mL glass centrifuge tube, and 10 mL of 1-propanol was added to precipitate the first semiconductor nanoparticles. After centrifugation (2500 rpm, 2 minutes), the supernatant solution was discarded, and the brown precipitate (first semiconductor nanoparticles) was collected. 2 mL of chloroform was added to the collected precipitate and dissolved to obtain the dispersion of the first semiconductor nanoparticles of Example 1.

[0109] (Example 2) In Example 2, the amount of aluminum chloride in mixture B was changed to 0.075 mmol, OLA to 4 mL, and ODE in mixture A to 5 mL. The procedure was carried out in the same manner as in Example 1, except for these changes, to obtain a solution containing the first semiconductor nanoparticles and a dispersion of the first semiconductor nanoparticles according to Example 2. Figure 2 shows a list of the synthesis conditions in Examples 1 to 6 and the comparative example.

[0110] (Example 3) In Example 3, the amount of aluminum chloride in mixture B was changed to 0.05 mmol and the amount of OLA to 4 mL, and the procedure was carried out in the same manner as in Example 1, to obtain a solution containing the first semiconductor nanoparticles according to Example 3 and a dispersion of the first semiconductor nanoparticles, respectively.

[0111] (Example 4) In Example 4, the amount of OLA in mixture B was changed to 4 mL, and the reaction temperature was changed to 315°C, which is the boiling point of ODE. The rest of the procedure was carried out in the same manner as in Example 1 to obtain a solution containing the first semiconductor nanoparticles and a dispersion of the first semiconductor nanoparticles according to Example 4.

[0112] (Example 5) In Example 5, the reaction temperature was changed to 315°C, which is the boiling point of ODE, based on the synthesis conditions of Example 2. As a result, a solution containing the first semiconductor nanoparticles according to Example 5 and a dispersion of the first semiconductor nanoparticles were obtained, respectively.

[0113] (Example 6) In Example 6, based on the synthesis conditions of Example 4, the same amount of zirconium chloride was used instead of aluminum chloride. This yielded a solution containing the first semiconductor nanoparticles according to Example 6 and a dispersion of the first semiconductor nanoparticles, respectively.

[0114] (Example 7) In Example 7, the first semiconductor nanoparticles of Example 1 were coated with zinc sulfide (ZnS), and a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles were obtained by the following method.

[0115] To the solution containing the first semiconductor nanoparticles obtained in Example 1, zinc bis-diethyldithiocarbamate (Zn(DEDTC)) was used as the zinc source and sulfur source. ２ ) 1 mmol was added and the temperature was raised to 250°C to obtain a solution containing the second semiconductor nanoparticles of Example 7, in which the first semiconductor nanoparticles of Example 1 were covered with a ZnS shell.

[0116] Furthermore, to isolate the second semiconductor nanoparticles, the solution containing the second semiconductor nanoparticles was transferred to a 50 mL glass centrifuge tube, and 10 mL of 1-propanol was added to precipitate the second semiconductor nanoparticles. After centrifugation (2500 rpm, 2 minutes), the supernatant solution was discarded, and the brown precipitate (second semiconductor nanoparticles) was collected. 2 mL of chloroform was added to the collected precipitate and dissolved to obtain the dispersion of the second semiconductor nanoparticles of Example 7.

[0117] (Example 8) In Example 8, based on the conditions of Example 7, the solution containing the first semiconductor nanoparticles of Example 2 was used instead of the solution containing the first semiconductor nanoparticles of Example 1. This yielded a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles according to Example 8.

[0118] (Example 9) In Example 9, based on the conditions of Example 7, the solution containing the first semiconductor nanoparticles of Example 3 was used instead of the solution containing the first semiconductor nanoparticles of Example 1. This yielded a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles according to Example 9.

[0119] (Example 10) In Example 10, based on the conditions of Example 7, the solution containing the first semiconductor nanoparticles of Example 4 was used instead of the solution containing the first semiconductor nanoparticles of Example 1. This yielded a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles according to Example 10.

[0120] (Example 11) In Example 11, based on the conditions of Example 7, the solution containing the first semiconductor nanoparticles of Example 5 was used instead of the solution containing the first semiconductor nanoparticles of Example 1. This yielded a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles according to Example 11.

[0121] (Example 12) In Example 12, based on the conditions of Example 7, the solution containing the first semiconductor nanoparticles of Example 6 was used instead of the solution containing the first semiconductor nanoparticles of Example 1. This yielded a solution containing the second semiconductor nanoparticles and a dispersion of the second semiconductor nanoparticles according to Example 12.

[0122] (Comparative Example) In the comparative example, 1 mmol of barium bis-diisobutyldithiocarbamate (Ba(DiBuDTC)) ２ ), 1 mmol of zirconium tetrakisdiisobutyldithiocarbamate (Zr(DiBuDTC) ４ 5 mL of 1-octadecene was placed in a 50 mL two-necked flask and heated to 80°C under vacuum for 5 minutes while stirring with a magnetic stirrer to degas and dehydrate the reaction vessel. Argon was introduced into the reaction vessel and heated to 300°C, after which 4 mL of oleylamine solution was injected using a gas-tight syringe. After injection, heating was continued at 300°C for 30 minutes, and then allowed to cool to room temperature to obtain a solution containing the first semiconductor nanoparticles of the comparative example. Subsequently, the solution containing the first semiconductor nanoparticles was transferred to a 50 mL glass centrifuge tube, and 10 mL of 1-propanol was added to precipitate the nanoparticle components. After centrifugation (2500 rpm, 2 minutes), the supernatant solution was discarded and the brown precipitate (first semiconductor nanoparticles) was collected. 2 mL of chloroform was added to the collected precipitate and dissolved. This obtained a dispersion of the first semiconductor nanoparticles of the comparative example.

[0123] (Calculation of number-average particle size and particle size distribution of the first semiconductor nanoparticles in each example and comparative example) The shape of the first semiconductor nanoparticles in Examples 1 to 6 and the comparative example was observed using a transmission electron microscope (TEM), and their particle size was measured to calculate the number-average particle size. The particle size distribution was also calculated in the process.

[0124] Figure 3(a) shows a TEM image of the first semiconductor nanoparticle from Example 1, and Figure 3(b) shows a TEM image of the first semiconductor nanoparticle from Example 2. Figure 4(a) shows a TEM image of the first semiconductor nanoparticle from Example 3, and Figure 4(b) shows a TEM image of the first semiconductor nanoparticle from Example 4. Figure 5(a) shows a TEM image of the first semiconductor nanoparticle from Example 5, and Figure 5(b) shows a TEM image of the first semiconductor nanoparticle from Example 6. Figure 6 shows a TEM image of the first semiconductor nanoparticle of a comparative example.

[0125] 1-propanol was added to the dispersions of the first semiconductor nanoparticles obtained in Examples 1-6 and the Comparative Example, and a nanoparticle precipitate was obtained by centrifugation. The precipitate was then dispersed in toluene. Subsequently, a TEM grid, trade name Hi-ResoCarbon HRC-C10 STEM Cu100P grid (purchased from Oken Shoji), was used. Observation was then performed using a TEM (Hitachi High-Technologies Corporation, trade name H-7650).

[0126] The particle images obtained by TEM observation are shown in Figures 3 to 6, respectively. Considering the particle images as projections of spherical or polygonal objects, Image-J was used to perform elliptical fitting. Three or more TEM images were selected, and the particle size of all measurable nanoparticles (i.e., all particles except those whose images were cut off at the edges of the image) was measured. The observation range was 180 nm vertically and horizontally, and observations were performed in multiple fields of view until the particle sizes of 100 or more particles were measured. The number-average particle size was derived by calculating the geometric mean of the major and minor axes when the particle was fitted to an ellipse, and then calculating their arithmetic mean. At the same time, the variance was calculated and used as the particle size distribution (an indicator of the degree of particle size variation).

[0127] (Crystal Structure Analysis) - Crystal structure analysis of thin films of the first semiconductor nanoparticles and the second semiconductor nanoparticles. The dispersion of the first semiconductor nanoparticles in the comparative example and the dispersion of the second semiconductor nanoparticles in Example 7 were dropped onto a glass substrate, heated to 80°C and dried to obtain thin films. An X-ray diffractometer (Rigaku Corporation, "SmartLab type") was used to irradiate the obtained thin film with a parallel beam of CuKα rays (1.5418 Å), and the X-ray diffraction (XRD) pattern in the range of 2θ from 5 to 80° was measured by 2θ / θ measurement. The measurement conditions are shown below. Measurement device: SmartLab (manufactured by Rigaku Corporation) X-ray source: CuKα (1.5418 Å), output 45 kV, 200 mA Incident optical system: Parallel beam optical system Receiver side solar slit: 5.0° Slit: Incident side IS = 1.0 mm Receiver side RS1 = 1.0 mm, RS2 = 1.0 mm Scanning conditions: Scanning axis 2θ / θ Scanning speed: 2° / min Step width: 0.02°

[0128] Figure 7 shows the XRD measurement results of the first semiconductor nanoparticle thin film of the comparative example. As shown in Figure 7, the XRD measurement of the comparative thin film yielded BaZrS ３ A distinctive peak was identified. Figure 8 shows the XRD measurement results of the thin film of the second semiconductor nanoparticle in Example 7. As shown in Figure 8, in the XRD measurement of the thin film of the second semiconductor nanoparticle in Example 7, BaZrS ３ Furthermore, a peak characteristic of ZnS was confirmed. Note that both Example 7 and the Comparative Example contained BaZrS. ３ Its crystal structure is GdFeO3-type orthorhombic.

[0129] - Crystal structure analysis of the first and second semiconductor nanoparticles in solution The solution containing the first semiconductor nanoparticles from Example 5 and the solution containing the second semiconductor nanoparticles from Example 8 were concentrated at 170°C under vacuum using a Kugelrolle distillation apparatus (BUCHI, product name B-585) until the volume was reduced to approximately one-third of the original volume. The concentrated sample solutions were injected into X-ray analysis capillaries (Hilgenberg, Mark Tube) and sealed at both ends with UV-curing resin. The capillaries were attached to a dedicated attachment of an X-ray diffractometer (Rigaku, SmartLab), and in a parallel beam measurement system, the incident angle and detection angle of the apparatus were set to 0°, and a Z-axis scan was performed to record the point where the transmittance was at its minimum value. The Z-axis was set to the above value, the incident angle was set to 0°, and a 2θ scan was performed to measure the X-ray spectrum. The measurement conditions are shown below. Measurement device: SmartLab (manufactured by Rigaku Corporation) X-ray source: CuKα (1.5418 Å), output 45 kV, 200 mA Incident optical system: Parallel beam optical system Receiver side solar slit: 5.0° Slit: Incident side IS = 1.0 mm Receiver side RS1 = 1.0 mm, RS2 = 1.0 mm Scanning conditions: Scanning axis 2θ / θ Scanning speed: 2° / min Step width: 0.02°

[0130] Figure 9 shows the XRD measurement results in the solution of the first semiconductor nanoparticles in Example 5. As shown in Figure 9, in the XRD measurement of the solution of the first semiconductor nanoparticles in Example 5, BaZrS ３A distinctive peak was identified. Figure 10 shows the XRD measurement results in the solution of the second semiconductor nanoparticles of Example 8. As shown in Figure 10, the XRD measurement in the solution of the second semiconductor nanoparticles of Example 8 showed that BaZrS ３ Furthermore, a peak characteristic of ZnS was confirmed. Note that both Examples 5 and 8 contained BaZrS. ３ Its crystal structure is GdFeO3-type orthorhombic.

[0131] (Consideration of particle size) The common difference between the comparative examples and Examples 1-6 is the presence or absence of Lewis acid addition in mixture B, as shown in Figure 2. The nanoparticle shape could not be confirmed for the comparative examples. On the other hand, 0.1 mmol of AlCl added to mixture B. ３ In Example 1, where the additive was added, we succeeded in obtaining nanoparticles with a spherical or polyhedral shape and a number-average particle size of 4.9 nm (Figure 3(a)).

[0132] Furthermore, in Examples 2, 4, 5, and 6, in which 0.075 mmol or more of Lewis acid was added, nanoparticles with a spherical or polyhedral shape and a number-average particle size of 5 to 6.1 nm were obtained. In Example 3, in which 0.050 mmol of Lewis acid was added, nanoparticles with a plate-like or rod-like shape and a number-average particle size of 12.7 nm were obtained.

[0133] In other words, when the reaction was carried out at 300°C without adding Lewis acid to mixture B, the nanoparticle shape could not be confirmed for at least 30 minutes of reaction time (comparative example). ３ or ZrCl ４ When this substance was added, the generation of particulate matter and a decrease in particle size were observed in all temperature ranges.

[0134] Furthermore, when the amount of Lewis acid added was 0.050 mmol, the particle size distribution of the nanoparticles was within ±2.7 nm (Example 3), and when the amount of Lewis acid added was 0.075 mmol or 0.10 mmol, the particle size distribution of the nanoparticles was within ±1.0 nm (Examples 1, 2, 4, 5, and 6).

[0135] Lewis acids are expected to play a role in promoting the formation of nanoparticles. AlCl ３ or ZrCl４ Metal chlorides such as are known to have strong Lewis acidity. In this example, Ba(DiBuDTC) ２ and Zr (DiBuDTC) ４ It decomposes at high temperatures and becomes BaZrS ３ The process of generating this compound requires several steps, starting with a nucleophilic attack on the dithiocarbamate carbon moiety of the amine. The non-metallic and non-sulfur parts are eliminated and released into the solution to form the desired metal sulfide, and it is suspected that the metal chloride catalyzes this process.

[0136] Based on the above results, the metal chloride (AlCl) which has strong Lewis acidity and is the Lewis acid applied in the examples has strong Lewis acidity. ３ , ZrCl ４ It is expected that this will promote the generation of nanoparticles and suppress variations in particle size.

[0137] As described above, embodiments of the present invention have been explained, but these embodiments are presented as examples and are not intended to limit the scope of the present invention. Embodiments can be implemented in various forms other than those described above, and various omissions, substitutions, modifications, etc., can be made without departing from the spirit of the present invention. Embodiments and their variations are included in the scope and spirit of the present invention, as are the inventions described in the claims and their equivalents.

[0138] This application claims priority based on Japanese Patent Application No. 2025-020076, filed on 10 February 2025, and the entire contents of Japanese Patent Application No. 2025-020076 are incorporated herein by reference.

Claims

1. A method for producing chalcogenide perovskite particles containing a chalcogenide perovskite, comprising reacting a complex having a first metal atom, a complex having a second metal atom, and a Lewis acid in a solvent in the liquid phase.

2. The manufacturing method according to claim 1, wherein the complex having the first metal atom and the complex having the second metal atom each have ligands that do not contain oxygen atoms (O) and halogen atoms (X) as coordinating atoms.

3. The manufacturing method according to claim 1 or claim 2, wherein the complex having the first metal atom and the complex having the second metal atom each have a ligand that coordinates with an atom selected from the group consisting of nitrogen (N), sulfur (S), selenium (Se), tellurium (Te), carbon (C), and phosphorus (P).

4. The manufacturing method according to claim 2 or 3, wherein the ligand is a dithiocarbamate, xanthate, trithiocarbamate, dithioester, thiolate, sulfide, or a compound in which some or all of the sulfur atoms contained therein are substituted with a selenium atom or a tellurium atom, alkylamine, arylamine, trialkylsilylamine, nitrogen-containing aromatic ring, alkane, unsaturated hydrocarbon ring, or a group derived from the unsaturated hydrocarbon ring, cyanide, trialkylphosphine, triarylphosphine, or diphosphine.

5. The manufacturing method according to any one of claims 1 to 4, wherein the metal atom of the complex having the first metal atom comprises at least one of Sr and Ba, and the metal atom of the complex having the second metal atom comprises at least one of Zr and Hf.

6. The manufacturing method according to claim 5, wherein at least one of the metal atoms of the complex having the first metal atom and the metal atoms of the complex having the second metal atom further comprises at least one selected from Ti, Ca, and Mg.

7. The manufacturing method according to any one of claims 1 to 6, wherein the complex having the first metal atom and the complex having the second metal atom are a single compound, forming a binuclear complex.

8. The manufacturing method according to claim 7, wherein the metal atom of the complex having the first metal atom and the metal atom of the complex having the second metal atom are bonded via a ligand coordinated by a sulfur atom, a selenium atom, or a tellurium atom.

9. The method for producing the chalcogenide perovskite according to any one of claims 1 to 8, wherein the chalcogenide perovskite has a composition represented by the following formula (101) or (102): ABCh ３ ...(101) A' ２ A ｎ－１ B ｎ Ch ３ｎ＋１ ... (102) (However, in formulas (101) and (102), A and A' are Mg, Ca, Sr, Ba, or any combination thereof in any ratio, B is Ti, Zr, Hf, or any combination thereof, and Ch is S, Se, Te, or any combination thereof in any ratio. In formula (102), n is an integer between 1 and 10, and A and A' may be the same or different from each other. The chalcogenide perovskite includes a solid solution in which some or all of A, A', B, and Ch are substituted with other elements in the composition represented by formula (101) or (102).) 10. The manufacturing method according to any one of claims 1 to 9, wherein a chalcogen compound is further added to the liquid phase.

11. The manufacturing method according to any one of claims 1 to 10, wherein an amine compound is further added to the liquid phase.

12. The manufacturing method according to any one of claims 1 to 11, wherein the reaction is produced by adding a second raw material, which contains at least the raw material components not included in the first raw material, to a first raw material component containing at least the solvent, from among the raw material components comprising the first metal atom-containing complex, the second metal atom-containing complex, the Lewis acid, and the solvent.

13. The manufacturing method according to claim 12, wherein at least one of the first raw material and the second raw material is preheated, and the second raw material is added to the first raw material to cause the reaction.

14. The manufacturing method according to claim 12, wherein the second raw material is added to the first raw material, and then the first and second raw materials are heated to produce the reaction.

15. A method for producing the product according to any one of claims 1 to 11, comprising simultaneously mixing the complex having the first metal atom, the complex having the second metal atom, the Lewis acid, and at least one of the chalcogen compound and the amine compound to produce the reaction.

16. The manufacturing method according to claim 15, wherein the reaction is produced by flowing the complex having the first metal atom, the complex having the second metal atom, the Lewis acid, and at least one of the chalcogen compound and the amine compound as separate flows and simultaneously combining the flows.

17. The manufacturing method according to claim 15 or claim 16, wherein the complex having the first metal atom, the complex having the second metal atom, the Lewis acid, the chalcogen compound, the complex having the first metal atom, the complex having the second metal atom, the Lewis acid, the amine compound, or the complex having the first metal atom, the complex having the second metal atom, the Lewis acid, the chalcogen compound, and the amine compound are preheated.

18. The manufacturing method according to claim 14, wherein a dispersion in which the complex having the first metal atom, the complex having the second metal atom, and the Lewis acid are dispersed in a dispersion medium is formed into a film by a coating method, a spray method, a doctor blade method, or an inkjet method, and the obtained coating film is heat-treated to obtain the chalcogenide perovskite particles.

19. Chalcogenide perovskite particles containing chalcogenide perovskite, wherein the particle size distribution obtained from TEM observation is within ±8.0 nm.

20. The chalcogenide perovskite particle according to claim 19, wherein the particle size distribution obtained from TEM observation is within ±2.0 nm.

21. The chalcogenide perovskite particle according to claim 19 or claim 20, wherein the number-average particle size obtained from TEM observation is 15 nm or less.

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