JP6077946B2 - ITO nanoparticles and manufacturing method thereof - Google Patents

Description

  The present invention relates to an ITO nanoparticle having a macrocyclic π-conjugated compound as a ligand, and more specifically, characterized in that the macrocyclic π-conjugated compound is coordinated with the nanoparticle in a planar direction. The present invention relates to ITO nanoparticles and a method for producing the same.

  In general, as a method for producing nanoparticles of tin-doped indium oxide (hereinafter abbreviated as ITO), a gas phase method such as a CVD method or a spray pyrolysis method, and a wet method using a chemical reduction reaction are known. Since ITO nanoparticles produced by a conventional wet method have high agglomeration properties and it is difficult to obtain monodisperse particles, most of the high-purity nanoparticles with little aggregation have been produced by a gas phase method. On the other hand, ITO nanoparticles obtained by a vapor phase method are excellent in monodispersity, but have a problem that production costs are high and particle size control is difficult. Then, the wet manufacturing method of the ITO nanoparticle excellent in the dispersibility is tried.

  Several methods have been proposed for wet manufacturing methods of ITO nanoparticles. For example, an aqueous solution containing indium and a small amount of tin salt is reacted with alkali to co-precipitate indium and tin hydroxides, remove unnecessary salts, and then heat-fired in the atmosphere to form oxides. And a method using a mixture of these instead of coprecipitation (for example, see Patent Documents 1 and 2). Usually, in order to impart high dispersion stability to nanoparticles, for example, a method using a dispersant and a method of adding a binder and a pH adjuster (for example, see Patent Document 3) have been proposed. There is concern that the ratio will increase and the purity of the ITO nanoparticle dispersion will decrease.

  Therefore, in order to impart high dispersibility without requiring a dispersant or a special dispersion treatment, a method for producing organic-coordinated ITO nanoparticles in which a small amount of an organic layer is coordinated on the surface of ITO nanoparticles (for example, (See Patent Document 4 and Non-Patent Document 1).

Japanese Patent Laid-Open No. 62-7627 (for example, refer to the claims) Japanese Patent Laid-Open No. 07-070481 (for example, refer to the claims) Japanese Laid-Open Patent Publication No. 09-156025 (see, for example, the claims) Japanese Patent Laying-Open No. 2011-12233 (see, for example, the claims) Japanese Patent Laying-Open No. 2006-80346 (for example, refer to the claims)

J. et al. Am. Chem. Soc. 2009, 131, 17736-17737

  The methods described in Patent Document 4 and Non-Patent Document 1 produce monodisperse nanoparticles by coordinating a small amount of organic substances on the surface of the particles. In Patent Document 4, alcohols such as ethylene glycol are used. In Non-Patent Document 1, since oleylamine, which is a long-chain amine, is used as a ligand, the volume ratio of the ligand to the entire volume of the nanoparticle increases, and the interparticle distance between the nanoparticles is increased. There was a problem of getting away. In contrast, by coordinating a planar ligand such as a macrocyclic π-conjugated compound in the planar direction with respect to the particle, the volume ratio of the ligand is expected to decrease, and the interparticle distance becomes closer. However, there have been no reports on nanoparticles that planarly coordinate such planar molecules.

  In Patent Document 5, it is reported that a porphyrin derivative, which is a macrocyclic π-conjugated compound, is used as a ligand for metal nanoparticles. It has a structure that binds to the particles, and does not coordinate to the nanoparticles in the planar direction.

  As a result of intensive studies to solve the above problems, the inventors of the present invention have a specific compound as a ligand, and ITO nanoparticles in which the compound is coordinated in a specific direction have excellent dispersibility and are more easily produced. The inventors have found that this is possible and have completed the present invention.

  That is, the present invention relates to ITO nanoparticles in which a macrocyclic π-conjugated compound is liganded as a ligand on the surface of ITO particles, and the compound is coordinated in a plane direction with respect to the particles, and the production thereof It is about the method.

  Hereinafter, the present invention will be described in detail.

  The ITO nanoparticles of the present invention are characterized by having a macrocyclic π-conjugated compound as a ligand, and the macrocyclic π-conjugated compound is solvated with the dispersion solvent, so that a special dispersant or special operation is performed. In this case, a dispersion having excellent monodispersibility can be obtained simply by adding the ITO nanoparticles to a dispersion solvent. In general, organic substances used as ligands for nanoparticles are known to improve dispersibility by using polymers or small molecules having a long chain length. In order to produce nanoparticles that exhibit excellent dispersibility without giving a long chain length or polymerizing, the macrocyclic π-conjugated compound is multidentately coordinated with the ITO nanoparticles. Is possible.

  The ITO nanoparticles of the present invention are characterized in that the macrocyclic π-conjugated compound is coordinated to the nanoparticles in the planar direction. The macrocyclic π-conjugated compound here refers to a compound containing four or more cyclic structures in the same plane, such as porphyrin and phthalocyanine, and derivatives thereof, and includes not only one kind of compound but also 2 Two or more kinds of macrocyclic π-conjugated compounds can be used in combination.

  These macrocyclic π-conjugated compounds become compounds having a large plane when π electrons are conjugated. By this π conjugation, not only the planes can be easily stacked by π-π interaction, but also by coordinating with ITO nanoparticles in a plane, the π conjugate orbitals hybridize with the metal orbits of the ITO nanoparticles, creating new orbitals. Can be formed. In other words, by planar coordination on the surface of ITO nanoparticles, orbital interactions occur between the π orbitals of the macrocyclic π conjugated compounds and the metal orbitals of the nanoparticles, and the electrical properties specific to the nanoparticles are exhibited. It becomes possible to grant.

  Examples of macrocyclic π-conjugated compounds include the following general formulas (1) to (4).

Wherein R _{1 to} R ₄₈ are each independently a hydrogen atom, a halogen atom, an amino group, a carboxyl group, a thiol group, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms; A linear, branched or cyclic alkyl group having 1 to 10 carbon atoms having any functional group selected from a group, a carboxyl group, a thiol group and a hydroxyl group; an oxygen atom, a sulfur atom, a carbonyl group in the carbon chain; A C1-C10 linear, branched or cyclic alkyl group containing an ester group, an amide group or an imino group is represented.)
Specific examples of the compounds represented by the general formulas (1) to (4) are not particularly limited, and examples thereof include the following compounds:

Among them, since it can be stably coordinated to ITO nanoparticles, exemplary compound 1-4, exemplary compound 1-7, exemplary compound 1-11, exemplary compound 1-14, exemplary compound 2-3, exemplary compound 2 -5, exemplary compound 2-9, exemplary compound 2-12, exemplary compound 3-3, exemplary compound 3-4, exemplary compound 3-5, exemplary compound 3-9, exemplary compound 3-11, exemplary compound 3-12 It is particularly preferable to use Exemplified Compound 4-4, Exemplified Compound 4-5, Exemplified Compound 4-8, and Exemplified Compound 4-10.

  The ITO nanoparticles of the present invention preferably have an average particle diameter of 3 to 60 nm, more preferably 4 to 50 nm, particularly 4 to 50 nm, as measured by a transmission electron microscope from the viewpoint of the ratio of the macrocyclic π-conjugated compound and the transparency of the dispersion. Preferably it is 5-40 nm.

Regarding the average particle diameter of the ITO nanoparticles of the present invention, a carbon coating in which a low-concentration dispersion having a concentration of 0.01% by weight or less in which the ITO nanoparticles are dispersed in an appropriate solvent is prepared, and this is coated with a collodion film. Measurement is performed by dropping the solution onto a copper mesh to volatilize the solvent and observing with a transmission microscope. And for the measurement of the average particle diameter of ITO nanoparticles, a photograph of an image observed at a magnification of 100,000 times is taken, the particle diameters of 300 or more particles are measured, and averaged to obtain an average particle diameter. Ask for.
In the ITO nanoparticles of the present invention, the content of the macrocyclic π conjugated compound as a ligand is preferably 1 to 20% by weight of the total weight of the particles from the viewpoint of dispersibility of the nanoparticles and ITO purity, more preferably It is 2 to 18% by weight, more preferably 3 to 15% by weight.

  As a specific method for measuring the coordination amount of the macrocyclic π-conjugated compound, a method for measuring the coordination amount of the macrocyclic π-conjugated compound using a differential thermothermal gravimetric simultaneous measurement apparatus (TG / DTA) is shown.

  After filtering the ITO nanoparticle dispersion with a 0.5 μm filter, it is dried at 90 ° C. under reduced pressure to prepare an ITO nanoparticle powder, and a differential thermothermal gravimetric simultaneous measurement device (TG / DTA) (SII (Trade name: TG / DTA6200, manufactured by Nanotechnology Co., Ltd.), held at 100 ° C. for 60 minutes in a nitrogen atmosphere, then heated up to 500 ° C. at 10 ° C. per minute, then held at 500 ° C. for 180 minutes, The decrease in weight in the range of from 0C to 500C is taken as the coordination amount of the macrocyclic π-conjugated compound.

  Since the ITO nanoparticle of the present invention is coordinated so that the macrocyclic π-conjugated compound covers the surface of the ITO nanoparticle, the macrocyclic π-conjugated compound is solvated with the dispersion solvent, ITO nanoparticles exhibit high dispersibility in solvents.

  When the ITO nanoparticles are dispersed at a concentration of 0.01% by weight with respect to a suitable dispersion solvent, the solution haze of the dispersion is preferably 5% or less. The solution haze at this time is measured according to JIS K 7136 by using a liquid cell having a thickness of 10 mm using a Nippon Denshoku Industries Co., Ltd. haze meter (trade name NDH-5000). The dispersion solvent used is not particularly limited as long as the ITO nanoparticles can be dispersed. For example, water, methanol, ethanol, propanol, isopropyl alcohol, butanol, hexanol, heptanol, octanol, decanol, cyclohexanol Alcohols such as terpineol, glycols such as ethylene glycol and propylene glycol, ketones such as acetone, methyl ethyl ketone and diethyl ketone, esters such as ethyl acetate, butyl acetate and benzyl acetate, methoxyethanol and ethoxy Ether alcohols such as ethanol, ethers such as dioxane and tetrahydrofuran, amides such as N, N-dimethylformamide, ethanolamine, diethanolamine, trie Amines such as noramine, aromatic hydrocarbons such as benzene, toluene, xylene, trimethylbenzene, and dodecylbenzene, hexane, heptane, octane, nonane, decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, Solvents that are liquid at room temperature such as long-chain alkanes such as nonadecane, eicosane, and trimethylpentane, and cyclic alkanes such as cyclohexane, cycloheptane, and cyclooctane may be appropriately selected and used.

  In addition, as another evaluation of dispersibility, for example, the above dispersion can be centrifuged to confirm that the ITO nanoparticles do not settle. As evaluation conditions at this time, a centrifuge (manufactured by Kokusan Co., Ltd., (trade name) H-201F) equipped with an angle rotor with a rotation radius of 10.1 cm was used, and the dispersion was 3,000 rpm for 30 minutes. Whether or not to separate into a sedimented layer of ITO nanoparticles and a transparent supernatant is determined visually.

  The ITO nanoparticles of the present invention can be produced by performing two-step ligand exchange. More specifically, a carboxylic acid compound which is produced as an ITO nanoparticle precursor having a linear or branched alcohol or amine having 6 to 24 carbon atoms as a ligand and is exchanged by ligand exchange. ITO as a ligand (ITO nanoparticle intermediate) is produced. Next, by further ligand exchange of this carboxylic acid, ITO nanoparticles having a macrocyclic π-conjugated compound as a ligand (cyclic compound coordinated ITO nanoparticles) can be produced.

  Initially, the manufacturing method of an ITO nanoparticle precursor is demonstrated.

  As a method for producing an ITO nanoparticle precursor, for example, a known one-step synthesis method described in Non-Patent Document 1 using a linear or branched alcohol or amine having 6 to 24 carbon atoms is known. Can be mentioned.

  The straight-chain or branched alcohols or amines having 6 to 24 carbon atoms to be used may have either a monodentate coordination or multidentate coordination with respect to the ITO nanoparticles, such as hexanol, octanol, 2 -Ethylhexanol, decanol, lauryl alcohol, myristyl alcohol, hexadecanol, oleyl alcohol, tetracosanol, hexylamine, octylamine, decylamine, undecylamine, dodecylamine, tridecylamine, tetradecylamine, pentadecylamine, Examples include hexadecylamine, heptadecylamine, stearylamine, nonadecylamine, oleylamine, hexamethylenediamine and the like.

  The ITO nanoparticle intermediate can be produced by ligand exchange of the ITO nanoparticle precursor with a carboxylic acid compound. The term “carboxylic acid compound” as used herein refers to a low molecular weight compound having at least one carboxyl group and having a molecular weight of 350 or less. That is, it includes not only monocarboxylic acids but also dicarboxylic acids, tricarboxylic acids, tetracarboxylic acids, and other carboxylic acid derivatives. Further, not only one type but also two or more types of carboxylic acid compounds can be used in combination. Examples of carboxylic acid compounds include, for example, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearin Saturated monocarboxylic acids such as acids, unsaturated monocarboxylic acids such as oleic acid, linoleic acid, linolenic acid, arachidonic acid, eicosapentaenoic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid, salicylic acid, gallic acid, melittic acid , Aromatic carboxylic acids such as cinnamic acid, oxalic acid, malonic acid, tartaric acid, succinic acid, itaconic acid, glutaric acid, adipic acid, α-ketoglutaric acid, malic acid, oxaloacetic acid, fumaric acid, maleic acid, etc. Trica such as acid, citric acid, isocitric acid, oxalosuccinic acid, aconitic acid Bon acid, ethylene tetracarboxylic acid, tetracarboxylic acids such as Mesobutan-1,2,3,4-tetracarboxylic acid. Moreover, ITO nanoparticles having particularly high dispersibility can be obtained by using one or more carboxylic acid compounds selected from oxalic acid, malonic acid, and succinic acid as a ligand among the above carboxylic acid compounds. . This is because oxalic acid, malonic acid, and succinic acid all have a structure that can be easily coordinated to the ITO nanoparticles and are highly soluble in general solvents such as water.

  In the ligand exchange reaction for producing the ITO nanoparticle intermediate, it is preferable to use a solvent, and the solvent to be used is not particularly limited as long as it dissolves a carboxylic acid compound as a ligand. , Water, methanol, ethanol, propanol, isopropyl alcohol, butanol, hexanol, heptanol, octanol, decanol, cyclohexanol, terpineol, and other alcohols, ethylene glycol, propylene glycol, and other glycols, acetone, methyl ethyl ketone, and diethyl ketone Ketones such as ethyl acetate, butyl acetate and benzyl acetate, ether alcohols such as methoxyethanol and ethoxyethanol, ethers such as dioxane and tetrahydrofuran, , N-dimethylformamide, acid amides such as ethanolamine, diethanolamine, triethanolamine, amines, aromatic hydrocarbons such as benzene, toluene, xylene, trimethylbenzene, and dodecylbenzene, hexane, heptane, octane, nonane, Liquid at room temperature, such as long-chain alkanes such as decane, undecane, dodecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, nonadecane, eicosane, and trimethylpentane, and cyclic alkanes such as cyclohexane, cycloheptane, and cyclooctane These solvents may be appropriately selected and used.

  The amount of the carboxylic acid compound is preferably such that a large excess of the carboxylic acid compound is used with respect to the ITO nanoparticle precursor in order to rapidly advance the ligand exchange reaction. The term “large excess” as used herein refers to the use of a carboxylic acid compound having a mole number three times or more of the total mole number of indium and tin in the ITO nanoparticle precursor.

  The temperature at which the ITO nanoparticle intermediate is obtained can be set according to the characteristics of the solvent used, and is preferably 60 ° C. or higher, and more preferably 70 ° C. or higher in order to allow the ligand exchange reaction to proceed more rapidly. The reaction time can be appropriately set according to the reaction temperature, preferably 5 hours or longer, and can be determined while confirming the progress of the exchange reaction. As a method for confirming the progress of the reaction, for example, the reaction solution is centrifuged to isolate ITO nanoparticles, and from the 1H NMR spectrum or 13C NMR spectrum of the ITO nanoparticles, alcohols that are ligands before exchange or By calculating the ratio of the amines and the carboxylic acid compound that is the ligand after the exchange, it is possible to calculate the exchange ratio from the ITO nanoparticle precursor to the ITO nanoparticle intermediate. In this case, the ratio of the carboxylic acid compound that is the ligand after the exchange is 8 times or more that of the alcohol or amine that is the ligand before the exchange, and thus the ligand exchange reaction has proceeded. Judged to be.

  The ITO nanoparticle intermediate obtained by ligand exchange is obtained by replacing only the ligand portion from the ITO nanoparticle precursor, and the shape of the ITO nanoparticle itself hardly changes. The appearance of the ITO nanoparticles can be confirmed by observing a TEM image. The average particle diameter of the ITO nanoparticle intermediate after ligand exchange is the same as that of the ITO nanoparticle precursor before ligand exchange. In comparison, it is within ± 10%.

  In addition, it is preferable that the atmosphere at the time of reaction is oxygen-free conditions, and it is especially preferable that it is in nitrogen stream.

  And the ITO nanoparticle intermediate with a lower impurity concentration can be obtained by refining the obtained ITO nanoparticle intermediate, for example, centrifuge purification. In this case, centrifuge purification is performed by separating the obtained reaction solution or dispersion into ITO nanoparticles and supernatant using a centrifugal separator, and after removing the supernatant, it is dispersed in the precipitated ITO nanoparticles precipitate. This is a method of washing the ITO nanoparticle intermediate by adding a solvent and redispersing, and if necessary, adding a precipitation solvent in which the ITO nanoparticle intermediate settles, and repeating the centrifugation.

  The dispersion solvent to be used is not particularly limited as long as the ITO nanoparticle intermediate is sufficiently dispersed and settled, for example, water; methanol, ethanol, 1-propanol, 2-propyl alcohol, butanol, hexanol. , Heptanol, octanol, decanol, cyclohexanol, echinene, and terpineol; alcohols such as ethyl acetate, butyl acetate, and benzyl acetate; ether alcohols such as methoxyethanol and ethoxyethanol; N, N-dimethyl Examples include acid amides such as formamide, ethanolamine, diethanolamine, and triethanolamine, and amines. Among them, water, methanol, ethanol, 2-propanol, N, N-dimethylformua are highly dispersible and practical. It is preferable to use a de.

  The precipitation solvent is not particularly limited, and for example, aromatic hydrocarbons such as toluene, xylene, mesitylene, benzene, dichlorobenzene, nitrobenzene; n-heptane, n-hexane, n-octane, cyclohexane, decahydro Aliphatic hydrocarbons such as naphthalene; ketones such as acetone, methyl ethyl ketone, diethyl ketone, acetylacetone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, N-methylpyrrolidone; diethyl ether, tetrahydrofuran, dioxane, methoxyethanol, ethoxyethanol, etc. Ethers; chlorinated aliphatic hydrocarbons such as dichloromethane, chloroform, 1,2-dichloroethane; and acetates such as ethyl acetate, butyl acetate, and amyl acetate. From height and practicality of sedimentary also chloroform, dichloromethane acetone, it is preferable to use methyl ethyl ketone.

  In addition, there are no particular restrictions on the conditions of the centrifugal separator as long as the ITO nanoparticles and the supernatant can be separated at the time of centrifugal purification, for example, a centrifuge equipped with an angle rotor with a rotation radius of 10.1 cm, for example. Using (Kokusan Co., Ltd., (trade name) H-201F), the dispersion can be separated by centrifugation at 10,000 rpm for 30 minutes.

  The obtained ITO nanoparticle intermediate can be subjected to ligand exchange to produce a target macrocyclic π-conjugated compound coordinated ITO nanoparticle. More specifically, ITO nanoparticle intermediate and macrocyclic π-conjugated compound are heated and stirred in a solvent at a temperature of 60 ° C. or higher, and further at 70 ° C. or higher, for 10 hours or longer, thereby ligand exchange. It is preferable to perform the determination while confirming the progress of the exchange reaction.

  As a method for confirming the progress of the reaction, confirmation is made by laser Raman spectroscopy. By centrifuging the reaction liquid to isolate ITO nanoparticles, irradiating the dispersion liquid in which the nanoparticles are dispersed in a dispersion solvent with laser light having an excitation wavelength of 785 nm, and measuring light scattering in the near infrared to visible range A peak peculiar to a macrocyclic π-conjugated compound can be confirmed. In addition, since the carboxylic acid compound which is an intermediate ligand does not show a peculiar peak in the same region, the progress of the reaction can be confirmed by the presence or absence of the peak. When no change was observed in the peak shape, it was judged that the ligand exchange reaction was sufficiently advanced.

  The amount of the macrocyclic π-conjugated compound to be used is preferably a large excess of the macrocyclic π-conjugated compound with respect to the ITO nanoparticle intermediate in order to rapidly advance the ligand exchange reaction. The term “large excess” as used herein refers to the use of a macrocyclic π-conjugated compound having a mole number of 1/50 or more of the total mole number of indium and tin in the ITO nanoparticle intermediate.

  The solvent used in the ligand exchange reaction for producing the macrocyclic π-conjugated compound ligand ITO nanoparticles is not particularly limited as long as it dissolves the macrocyclic π-conjugated compound as a ligand. Water, methanol, ethanol, propanol, isopropyl alcohol, butanol, hexanol, heptanol, octanol, decanol, cyclohexanol, alcohols such as terpineol, glycols such as ethylene glycol and propylene glycol, acetone, methyl ethyl ketone, and diethyl ketone Ketones, esters such as ethyl acetate, butyl acetate and benzyl acetate, ether alcohols such as methoxyethanol and ethoxyethanol, ethers such as dioxane and tetrahydrofuran, N, N-dimethyl Acid amides such as formamide, ethanolamine, diethanolamine, triethanolamine, amines, aromatic hydrocarbons such as benzene, toluene, xylene, trimethylbenzene, and dodecylbenzene, hexane, heptane, octane, nonane, decane, undecane Select a suitable solvent at room temperature such as long-chain alkanes such as dodecane, tridecane, tetradecane, pentadecane, hexadecane, octadecane, nonadecane, eicosane, and trimethylpentane, and cyclic alkanes such as cyclohexane, cycloheptane, and cyclooctane. Can be used.

  The target macrocyclic π-conjugated compound coordinated ITO nanoparticles obtained by ligand exchange are those in which only the ligand portion is exchanged from the ITO nanoparticle intermediate, and the ITO nanoparticles themselves The shape hardly changes. The appearance of the ITO nanoparticles can be confirmed by observing a TEM image, and the average particle size of the macrocyclic π-conjugated compound coordinated ITO nanoparticles after ligand exchange is the ITO before ligand exchange. It is within ± 10% compared to the nanoparticle intermediate.

  In addition, it is preferable that the atmosphere at the time of reaction is oxygen-free conditions, and it is especially preferable in nitrogen stream.

  Then, by purifying the obtained macrocyclic π-conjugated compound coordinated ITO nanoparticles, for example, by centrifugation, ITO nanoparticles having a lower impurity concentration can be obtained. In this case, centrifuge purification is performed by separating the obtained reaction solution or dispersion into ITO nanoparticles and supernatant using a centrifugal separator, and after removing the supernatant, it is dispersed in the precipitated ITO nanoparticles precipitate. This is a method of washing the ITO nanoparticles by adding a solvent and redispersing, and if necessary, adding a precipitation solvent in which the ITO nanoparticles settle, and repeating the centrifugation.

  The dispersion solvent to be used is not particularly limited as long as the macrocyclic π-conjugated compound coordinated ITO nanoparticles are sufficiently dispersed and settled, for example, water; methanol, ethanol, 1-propanol, 2-propyl alcohol. , Butanol, hexanol, heptanol, octanol, decanol, cyclohexanol, echene, and terpineol; alcohols such as ethyl acetate, butyl acetate, and benzyl acetate; ether alcohols such as methoxyethanol and ethoxyethanol; N , N-dimethylformamide, acid amides such as ethanolamine, diethanolamine and triethanolamine, amines, etc. Among them, water, methanol, ethanol, 2-propanol, N, N- The It is preferred to use a solution of triethylsilane.

  The precipitation solvent is not particularly limited, and for example, aromatic hydrocarbons such as toluene, xylene, mesitylene, benzene, dichlorobenzene, nitrobenzene; n-heptane, n-hexane, n-octane, cyclohexane, decahydro Aliphatic hydrocarbons such as naphthalene; ketones such as acetone, methyl ethyl ketone, diethyl ketone, acetylacetone, methyl isobutyl ketone, cyclopentanone, cyclohexanone, N-methylpyrrolidone; diethyl ether, tetrahydrofuran, dioxane, methoxyethanol, ethoxyethanol, etc. Ethers; chlorinated aliphatic hydrocarbons such as dichloromethane, chloroform, 1,2-dichloroethane; and acetates such as ethyl acetate, butyl acetate, and amyl acetate. From height and practicality of sedimentary also chloroform, dichloromethane acetone, it is preferable to use methyl ethyl ketone.

  In addition, there are no particular restrictions on the conditions of the centrifugal separator as long as the conditions allow separation of the ITO nanoparticles and the supernatant during centrifugal purification. For example, by using a centrifuge (manufactured by Kokusan Co., Ltd., (trade name) H-201F) equipped with an angle rotor with a rotation radius of 10.1 cm, the dispersion is centrifuged at 10,000 rpm for 30 minutes. It is possible to separate.

  The ITO nanoparticle having the macrocyclic π-conjugated compound of the present invention as a ligand is obtained by coordinating the macrocyclic π-conjugated compound, which is the ligand, with the ITO nanoparticle in the planar direction. These macrocyclic π-conjugated compounds are compounds having a large plane, and it is known that π electrons are conjugated on this plane. By this π conjugation, not only the planes can be easily stacked by π-π interaction, but also by planar coordination with ITO nanoparticles, the π conjugate orbitals hybridize with the metal orbitals of the nanoparticles to form new orbits. can do. In other words, by planar coordination on the surface of ITO nanoparticles, orbital interaction occurs between the π orbitals of the macrocyclic π-conjugated compound and the metal orbitals of the nanoparticles, and electrical characteristics specific to ITO nanoparticles Can be given. Whether or not the macrocyclic π-conjugated compound is planarly coordinated can be confirmed by a change in absorption spectrum at 300 to 800 nm of a dispersion in which ITO nanoparticles are dispersed in an appropriate dispersion solvent. In general, macrocyclic π-conjugated compounds have characteristic absorption peaks called a Soret band near 300 to 500 nm and a Q band near 500 to 800 nm. On the other hand, in the ITO nanoparticles in which the macrocyclic π-conjugated compound is coordinated in a plane, the Soret band becomes broad and the Q band disappears due to the interaction between the π orbit of the macrocyclic π-conjugated compound and the metal orbit, or A phenomenon that remarkably decreases is confirmed. From this, it can be confirmed that the macrocyclic π-conjugated compound as a ligand is coordinated on the surface of the ITO nanoparticle in the planar direction.

  The present invention relates to an ITO nanoparticle having a macrocyclic π-conjugated compound as a ligand, and more specifically, the macrocyclic π-conjugated compound is coordinated in a planar direction with respect to the ITO nanoparticle. The present invention relates to ITO nanoparticles and a method for producing the same. It is expected that the macrocyclic π-conjugated compound is coordinated in the planar direction to express specific electrical characteristics that could not be obtained with conventional ITO nanoparticles, and the ITO nanoparticles of the present invention are simple. Because it can be mass-produced by simple methods, it can greatly contribute to the industry.

  EXAMPLES The present invention will be described in detail below with reference to examples, but the present invention is not limited to these examples.

<Purification of ITO nanoparticles>
The obtained ITO nanoparticle dispersion was purified by repeating centrifugation using a centrifuge (manufactured by Kokusan Co., Ltd., (trade name) H-201F).

<Preparation of ITO nanoparticle powder>
The aqueous dispersion of ITO nanoparticles was filtered through a 0.5 μm filter and then dried at 90 ° C. under reduced pressure to obtain ITO nanoparticle powder.

<Calculation of average particle diameter of ITO nanoparticles>
Prepare a dispersion with a concentration of 0.01% or less in which ITO nanoparticles are dispersed in a solvent such as water or alcohol, drop it onto a carbon-coated copper mesh with a collodion film, and volatilize the solvent. Observed with a scanning microscope. Further, the particle diameter of the ITO nanoparticles was read from the obtained image, and the average value of 300 or more ITO nanoparticles was defined as the average particle diameter.

<Coordination amount analysis of ligands in ITO nanoparticles>
The ITO nanoparticle powder was analyzed by thermogravimetry measurement. For the measurement, a differential thermal thermogravimetric simultaneous measurement apparatus (manufactured by SII Nano Technology, (trade name) EXSTAR TG / DTA6200) was used. The ITO nanoparticle powder is held at 100 ° C. for 60 minutes in a nitrogen atmosphere, then heated to 500 ° C. at 10 ° C. per minute, then held at 500 ° C. for 180 minutes, and weight loss in the range of 100 ° C. to 500 ° C. The value was calculated as the coordination amount of the thermally decomposed ligand.

<Confirmation of ligand exchange reaction progress from ITO nanoparticle precursor to ITO nanoparticle intermediate>
3 mL of the reaction solution was extracted and centrifuged to isolate ITO nanoparticles. When the sedimentation was poor, an equal amount of a halogen-based solvent such as dichloromethane was added to the reaction solution, and centrifugation was performed. The obtained ITO nanoparticles were dispersed in heavy water, and 1H NMR or 13C NMR was measured using a nuclear magnetic resonance apparatus (manufactured by JEOL Ltd., (trade name) JMN-EC400). From the obtained spectrum, the ratio of the ligand before exchange and the ligand after exchange was calculated, and it was judged that the reaction proceeded with a ratio of 8 times or more.

<Progression of ligand exchange reaction from ITO nanoparticle intermediate to macrocyclic π-conjugated compound coordinated ITO nanoparticle>
1 mL of the reaction solution was extracted and centrifuged to isolate ITO nanoparticles. When the sedimentation was poor, an equal amount of a halogen-based solvent such as dichloromethane was added to the reaction solution, and centrifugation was performed. The obtained ITO nanoparticles were dispersed in a solvent such as water or alcohol, and the laser Raman spectrum of the obtained dispersion was measured. The progress of the ligand exchange reaction was confirmed by the appearance of a peak peculiar to the macrocyclic π-conjugated compound and the change in the peak shape.

<Confirmation of planar coordination of macrocyclic π-conjugated compound>
A dispersion obtained by dispersing 0.001% by weight of macrocyclic π-conjugated compound coordinated ITO nanoparticles in a solvent such as water or alcohol was placed in a solution cell having an optical path length of 10 mm, and a spectrophotometer (manufactured by Hitachi High-Technology Corporation, (Trade name) U-4100), an absorption spectrum in a wavelength region of 300 to 800 nm was measured. By broadening the Soret band of the obtained absorption spectrum and decreasing the Q band, the conjugated π orbit of the macrocyclic π conjugated compound and the metal orbit of the ITO nanoparticle are mixed, that is, the macrocyclic π conjugated compound is planar to the ITO nanoparticle. Confirmed coordination.

<Solution haze of ITO nanoparticle dispersion>
A dispersion in which macrocyclic π-conjugated compound coordinated ITO nanoparticles are dispersed at a solid content concentration of 0.01% by weight with respect to a solvent such as water or alcohol is placed in a 10-mm-thick solution cell and a haze meter ( Using Nippon Denshoku Industries Co., Ltd. (trade name: NDH-5000), solution haze was measured according to JIS K7136.

<Production Example 1 of ITO Nanoparticle Precursor (Oleylamine Coordinated ITO Nanoparticle)>
A 100 ml flask was charged with 315 mg of indium (III) acetate, 39 μl of tin (II) 2-ethylhexanoate, 3.3 ml of oleylamine, 380 μl of 1-valeric acid, and 9 ml of n-dioctyl ether, and heated at 80 ° C. in a vacuum for 1 hour. Thereafter, the pressure was returned to normal pressure, and the mixture was heated at 150 ° C. for 1 hour in a nitrogen atmosphere, and then heated to reflux at 270 ° C. for 2 hours in a nitrogen atmosphere to obtain a crude dispersion of ITO nanoparticle precursor coordinated with oleylamine. The crude dispersion was repeatedly purified by centrifugal separation 5 times using ethanol as a precipitation solvent and hexane as a dispersion solvent to obtain an ITO nanoparticle precursor coordinated with oleylamine.

  When a diluted dispersion liquid in which a part of the obtained ITO nanoparticle precursor was dispersed in hexane was prepared and observed by TEM, the average particle diameter of the ITO nanoparticle precursor coordinated with oleylamine was 13.3 nm.

<Production Example 2 of ITO Nanoparticle Precursor (Hexadecylamine Coordinated ITO Nanoparticle)>
Into a 100 ml flask was charged 1176 mg of indium (III) 2-ethylhexanoate, 51 mg of tin (II) acetate, 4.5 ml of hexadecylamine, 700 μl of n-octanoic acid, and 25 ml of n-dioctyl ether, and 3 hours at 70 ° C. in vacuum. After heating, the pressure was returned to normal pressure, and the mixture was heated to reflux at 270 ° C. for 3 hours in a nitrogen atmosphere to obtain a coarse dispersion of ITO nanoparticle precursor coordinated with hexadecylamine. The crude dispersion was repeatedly purified by centrifugal separation 5 times using ethanol as a precipitation solvent and chloroform as a dispersion solvent, to obtain an ITO nanoparticle precursor coordinated with hexadecylamine.

  A diluted dispersion in which a part of the obtained ITO nanoparticle precursor was dispersed in chloroform was prepared and observed by TEM. The average particle diameter of the ITO nanoparticle precursor coordinated with hexadecylamine was 10.5 nm. there were.

<Production Example 3 of ITO Nanoparticle Precursor (1-Hexadecanol Coordinated ITO Nanoparticle)>
A 100 ml flask was charged with 1176 mg of indium (III) 2-ethylhexanoate, 139 μl of tin (II) 2-ethylhexanoate, 4.8 g of 1-hexadecanol, 800 μl of n-octanoic acid, and 20 ml of 1-octadecene. ITO nanoparticle heated at 80 ° C. for 1 hour, then returned to normal pressure, heated at 150 ° C. for 1 hour in a nitrogen atmosphere, then heated to reflux at 250 ° C. for 4 hours in a nitrogen atmosphere to coordinate 1-hexadecanol A crude precursor dispersion was obtained. The crude dispersion was repeatedly purified by centrifugal separation 5 times using echinene as a precipitation solvent and chloroform as a dispersion solvent, to obtain an ITO nanoparticle precursor coordinated with 1-hexadecanol.

  When a diluted dispersion liquid in which a part of the obtained ITO nanoparticle precursor was dispersed in chloroform was prepared and observed by TEM, the average particle diameter of the ITO nanoparticle precursor coordinated with 1-hexadecanol was 8. It was 9 nm.

<Production Example 4 of ITO Nanoparticle Precursor (Oleyl Alcohol Coordination ITO Nanoparticle)>
A 100 ml flask was charged with 315 mg of indium (III) acetate, 36 mg of tin (II) acetate, 2.5 ml of oleyl alcohol, 300 μl of 1-pentanoic acid and 10 ml of 1-octadecene, heated in vacuum at 70 ° C. for 1 hour, and then at atmospheric pressure. Then, the mixture was heated at 170 ° C. for 2 hours in a nitrogen atmosphere and then heated to reflux at 280 ° C. for 1.5 hours in a nitrogen atmosphere to obtain a crude dispersion of ITO nanoparticle precursor coordinated with oleyl alcohol. The crude dispersion was repeatedly centrifuged and purified 5 times using methanol as the precipitation solvent and hexane as the dispersion solvent, to obtain an ITO nanoparticle precursor coordinated with oleyl alcohol.

  When a diluted dispersion liquid in which a part of the obtained ITO nanoparticle precursor was dispersed in hexane was prepared and observed by TEM, the average particle diameter of the ITO nanoparticle precursor coordinated with oleyl alcohol was 7.1 nm. It was.

Example 1 (Exemplified Compound 1-14 Coordinated ITO Nanoparticle)
An oleylamine coordinated ITO nanoparticle precursor (prepared In + Sn = 1.2 mmol), 0.5 g of oxalic acid, and 30 ml of isopropanol obtained in Production Example 1 were placed in a 100 ml flask and heated at 80 ° C. for 7 hours in a nitrogen atmosphere. By stirring, a coarse dispersion of an ITO nanoparticle intermediate having oxalic acid as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having oxalic acid as a ligand. When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 13C NMR was measured, it contained 9.2 times oxalic acid as a ligand after exchange compared to oleylamine as a ligand before exchange. It was confirmed that the ligand exchange proceeded from oleylamine to oxalic acid.

  Next, the obtained ITO nanoparticle intermediate having oxalic acid as a ligand, 52 mg of the macrocyclic π-conjugated compound of Exemplified Compound 1-14, and 30 ml of isopropanol were charged into a 100 ml flask and heated at 80 ° C. for 50 hours in a nitrogen atmosphere. By stirring, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 1-14 as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 1-14.

  Next, when the obtained ITO nanoparticle precipitate was dispersed in isopropanol and observed with TEM, the average particle size of the ITO nanoparticles coordinated with the exemplified compound 1-14 was 13.2 nm, and the reaction precursor oleylamine From the 13.3 nm of the ITO nanoparticles coordinated with No, it is considered that only the ligand was exchanged.

  Further, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 1-14 was observed, and it was confirmed that the ITO nanoparticles had Exemplified Compound 1-14 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle is a compound in which Example Compound 1-14, which is a macrocyclic π-conjugated compound, is planarly coordinated on the surface of the ITO nanoparticle.

  Next, some of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 6.8% by weight of exemplified compound 1-14 as a ligand was coordinated. It was confirmed that.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles in which Exemplified Compound 1-14 was coordinated with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 2.2%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 1-14 exhibit sufficiently high dispersibility in water.

Example 2 (Exemplary Compound 2-3 coordinated ITO nanoparticles)
An oleylamine coordinated ITO nanoparticle intermediate (charged In + Sn = 1.2 mmol), 0.5 g of oxalic acid, and 30 ml of isopropanol obtained in Production Example 1 were placed in a 100 ml flask and heated in a nitrogen atmosphere at 80 ° C. for 7 hours. By stirring, a coarse dispersion of an ITO nanoparticle intermediate having oxalic acid as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having oxalic acid as a ligand. When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 13C NMR was measured, it contained 9.2 times oxalic acid as a ligand after exchange compared to oleylamine as a ligand before exchange. It was confirmed that the ligand exchange proceeded from oleylamine to oxalic acid.

  Next, the obtained ITO nanoparticles having oxalic acid as a ligand, 79 mg of the macrocyclic π-conjugated compound of Exemplified Compound 2-3, and 30 ml of isopropanol were charged into a 100 ml flask, and heated and stirred at 80 ° C. for 50 hours in a nitrogen atmosphere. Thus, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 2-3 as a ligand was obtained.

  The crude dispersion was repeatedly centrifuged and purified three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent, to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 2-3.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in isopropanol and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with Exemplified Compound 2-3 was 13.3 nm, and the reaction precursor oleylamine From the 13.3 nm of the co-ordinated ITO nanoparticles, it is considered that only the ligand was exchanged and coordinated.

  Moreover, when the laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 2-3 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 2-3 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 450 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly coordinating Exemplified Compound 2-3, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Next, a portion of the obtained ITO nanoparticles were dried to form a nanoparticle powder, and the thermogravimetric decrease was measured. As a result, the exemplified compound 2-3 as a ligand was coordinated with 6.3% by weight. It was confirmed that there was.

  In addition, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO particles coordinated with Exemplified Compound 2-3 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 3.5%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with Exemplified Compound 2-3 exhibit sufficiently high dispersibility in water.

Example 3 (Exemplary Compound 2-5 Coordinate ITO Nanoparticle)
Into a 100 ml flask was charged the oleylamine coordinated ITO nanoparticle intermediate (prepared In + Sn = 1.2 mmol) obtained in Production Example 1, 0.4 g of oxalic acid, and 30 ml of N, N-dimethylformamide in a nitrogen atmosphere. The mixture was heated and stirred at 80 ° C. for 7 hours to obtain a coarse dispersion of an ITO nanoparticle intermediate having oxalic acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and N, N-dimethylformamide as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having oxalic acid as a ligand. . When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 13C NMR was measured, it contained 9.3 times oxalic acid as a ligand after exchange compared to oleylamine as a ligand before exchange. It was confirmed that the ligand exchange proceeded from oleylamine to oxalic acid.

  Next, ITO nanoparticles having the oxalic acid as a ligand, 52 mg of the macrocyclic π-conjugated compound of Exemplified Compound 2-5, and 30 ml of N, N-dimethylformamide were charged into a 100 ml flask, and 100 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 30 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 2-5 as a ligand.

  The crude dispersion was repeatedly purified by centrifugation using N, N-dimethylformamide three times to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 2-5.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed by TEM, the average particle size of the ITO nanoparticles coordinated with the exemplified compound 2-5 was 13.1 nm, and the reaction Almost no change from 13.3 nm of the ITO nanoparticles coordinated by the precursor oleylamine, it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 2-5 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 2-5 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly coordinating the exemplified compound 2-5, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Next, a portion of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 5.8% by weight of the exemplified compound 2-5 as a ligand was coordinated. It was confirmed that.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 2-5 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 1.4%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 2-5 exhibit sufficiently high dispersibility in water.

Example 4 (Exemplified Compound 2-5 Coordinate ITO Nanoparticle)
Into a 100 ml flask was charged the ITO nanoparticle intermediate coordinated with hexadecylamine obtained in Production Example 2 (prepared In + Sn = 2.4 mmol), 2.9 g of citric acid, and 80 ml of ethanol. The mixture was heated and stirred for a time to obtain a crude dispersion of an ITO nanoparticle intermediate having citric acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and ethanol as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, 9.6 citric acid as a ligand after exchange was 9.6 compared with hexadecylamine as a ligand before exchange. It was confirmed that ligand exchange was proceeding from hexadecylamine to citric acid.

  Subsequently, ITO nanoparticles having citric acid as a ligand, 129 mg of macrocyclic π-conjugated compound of Exemplified Compound 2-5, and 80 ml of ethanol were charged into a 100 ml flask, and heated and stirred in a nitrogen atmosphere at 70 ° C. for 120 hours. Thus, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 2-5 as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and ethanol as a dispersion solvent to obtain a precipitate of Exemplified Compound 2-5 ITO nanoparticles.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in ethanol and observed by TEM, the average particle diameter of the exemplary compound 2-5ITO nanoparticles was 10.5 nm, and the reaction precursor, hexadecylamine ITO nanoparticles It is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 2-5 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 2-5 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly coordinating the exemplified compound 2-5, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Next, a portion of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 6.5% by weight of exemplified compound 2-5 as a ligand was coordinated. It was confirmed that.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 2-5 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 1.9%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 2-5 exhibit sufficiently high dispersibility in water.

Example 5 (Exemplary Compound 2-9 Coordinate ITO Nanoparticle)
Into a 100 ml flask was charged the ITO nanoparticle intermediate coordinated with hexadecylamine obtained in Production Example 2 (charged In + Sn = 2.4 mmol), 2.9 g of citric acid, and 80 ml of N, N-dimethylformamide. The mixture was heated and stirred at 90 ° C. for 10 hours in an atmosphere to obtain a coarse dispersion of an ITO nanoparticle intermediate having citric acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and N, N-dimethylformamide as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. . The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, 9.8% of citric acid as a ligand after exchange was 9.8% compared with hexadecylamine as a ligand before exchange. It was confirmed that ligand exchange was proceeding from hexadecylamine to citric acid.

  Next, ITO nanoparticles having the citric acid as a ligand, 129 mg of the macrocyclic π-conjugated compound of Exemplified Compound 2-9, and 80 ml of N, N-dimethylformamide were charged into a 100 ml flask, and 90 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 100 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 2-9 as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and N, N-dimethylformamide as a dispersion solvent to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 2-9.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed with a TEM, the average particle size of the ITO nanoparticles coordinated with Exemplified Compound 2-9 was 10.5 nm. There is almost no change from 10.5 nm of the ITO nanoparticles coordinated with the precursor hexadecylamine, and it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 2-9 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 2-9 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly aligning Exemplified Compound 2-9, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Next, a portion of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 6.6% by weight of exemplified compound 2-9 as a ligand was coordinated. It was confirmed that.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 2-5 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 2.6%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplified compound 2-9 exhibit sufficiently high dispersibility in water.

Example 6 (Exemplary Compound 3-3 Coordinated ITO Nanoparticle)
Into a 100 ml flask was charged the ITO nanoparticle intermediate coordinated with hexadecylamine obtained in Production Example 2 (prepared In + Sn = 2.4 mmol), 2.9 g of citric acid, and 80 ml of methanol. The mixture was heated and stirred for a time to obtain a crude dispersion of an ITO nanoparticle intermediate having citric acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and methanol as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, 9.6 citric acid as a ligand after exchange was 9.6 compared with hexadecylamine as a ligand before exchange. It was confirmed that ligand exchange was proceeding from hexadecylamine to citric acid.

  Next, ITO nanoparticles having the citric acid as a ligand, 202 mg of the macrocyclic π-conjugated compound of Exemplified Compound 3-3, and 80 ml of methanol were charged into a 100 ml flask, and heated and stirred in a nitrogen atmosphere at 60 ° C. for 150 hours. Thus, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 3-3 as a ligand was obtained.

  The crude dispersion was repeatedly centrifuged and purified three times using dichloromethane as a precipitation solvent and methanol as a dispersion solvent, to obtain a precipitate of ITO nanoparticles coordinated with Exemplary Compound 3-3.

  Next, when the obtained ITO nanoparticle precipitate was dispersed in methanol and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with Exemplified Compound 3-3 was 10.4 nm, and the reaction precursor hexa Almost no change was observed from 10.5 nm of ITO nanoparticles coordinated with decylamine, and it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 3-3 was observed, and the present ITO nanoparticles had Exemplified Compound 3-3 as a coordination ligand. Was confirmed. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 450 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle is obtained by planarly coordinating the exemplified compound 3-3, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticle.

  Next, a portion of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 8.0% by weight of Exemplified Compound 3-3 as a ligand was coordinated. It was confirmed that.

  In addition, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 3-3 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 0.8%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. Was not. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplified compound 3-3 exhibit sufficiently high dispersibility in water.

Example 7 (Exemplified Compound 1-14 Coordinated ITO Nanoparticle)
1-Hexadecanol coordinated ITO nanoparticle intermediate (prepared In + Sn = 2.6 mmol), malonic acid 1.6 g and N, N-dimethylformamide 80 ml obtained in Production Example 3 were charged in a 100 ml flask. Then, the mixture was heated and stirred in a nitrogen atmosphere at 100 ° C. for 8 hours to obtain a coarse dispersion of an ITO nanoparticle intermediate having malonic acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and N, N-dimethylformamide as a dispersion solvent to obtain a precipitate of an ITO nanoparticle intermediate having malonic acid as a ligand. . When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured, it was found that, compared with 1-hexadecanol which was a ligand before exchange, malonic acid which was a ligand after exchange was 8%. It was confirmed that the ligand exchange was proceeding from 1-hexadecanol to malonic acid.

  Next, ITO nanoparticles having malonic acid as a ligand, 151 mg of macrocyclic π-conjugated compound of Exemplified Compound 1-14, and 80 ml of N, N-dimethylformamide were charged into a 100 ml flask, and 100 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 80 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 1-14 as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation using N, N-dimethylformamide three times to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 1-14.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed with a TEM, the average particle diameter of the ITO nanoparticles coordinated with Exemplified Compound 1-14 was 8.9 nm. The 1-hexadecanol-protected ITO nanoparticles, which are precursors, hardly changed from 8.9 nm, and it is considered that only the ligand was exchanged.

  Further, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 1-14 was observed, and it was confirmed that the ITO nanoparticles had Exemplified Compound 1-14 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle is a compound in which Example Compound 1-14, which is a macrocyclic π-conjugated compound, is planarly coordinated on the surface of the ITO nanoparticle.

  Next, a part of the obtained ITO nanoparticles was dried to form a nanoparticle powder, and the thermal weight loss was measured. As a result, 9.8% by weight of Exemplified Compound 1-14 as a ligand was coordinated. It was confirmed that there was.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles in which Exemplified Compound 1-14 was coordinated with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 2.1%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 1-14 exhibit sufficiently high dispersibility in water.

Example 8 (Exemplified Compound 2-12 Coordinated ITO Nanoparticle)
1-Hexadecanol coordinated ITO nanoparticle intermediate (prepared In + Sn = 2.6 mmol), malonic acid 1.2 g, and N, N-dimethylformamide 80 ml obtained in Production Example 3 were placed in a 100 ml flask. Then, the mixture was heated and stirred in a nitrogen atmosphere at 90 ° C. for 8 hours to obtain a coarse dispersion of an ITO nanoparticle intermediate having malonic acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation using N, N-dimethylformamide three times to obtain a precipitate of an ITO nanoparticle intermediate having malonic acid as a ligand. When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured, it was found that, compared with 1-hexadecanol which was a ligand before exchange, malonic acid which was a ligand after exchange was 8%. It was confirmed that the ligand exchange proceeded from 1-hexadecanol to malonic acid.

  Next, ITO nanoparticles having malonic acid as a ligand, 268 mg of macrocyclic π-conjugated compound of Exemplified Compound 2-12, and 80 ml of N, N-dimethylformamide were charged into a 100 ml flask, and 90 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 80 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplified Compound 2-12 as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation using N, N-dimethylformamide three times to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 2-12.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with the exemplary compound 2-12 was 8.7 nm, and the reaction Almost no change was observed from 8.9 nm of the ITO nanoparticles coordinated with 1-hexadecanol, which is a precursor, and it is considered that only the ligand was exchanged.

  Moreover, when the laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 2-12 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 2-12 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 500 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle was obtained by planarly coordinating the exemplified compound 2-12, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticle.

  Subsequently, when a part of the obtained ITO nanoparticles were dried to form a nanoparticle powder and the thermogravimetric decrease was measured, the exemplified compound 2-12 as a ligand was coordinated with 6.9% by weight. It was confirmed that there was.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01% by weight of ITO nanoparticles coordinated with Exemplified Compound 2-12 with respect to 100% by weight of water. The solution haze of this dispersion was measured and found to be 3.9%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 2-12 exhibit sufficiently high dispersibility in water.

Example 9 (Exemplary Compound 3-5 Coordinate ITO Nanoparticle)
1-hexadecanol coordinated ITO nanoparticle intermediate (prepared In + Sn = 2.6 mmol), malonic acid 1.5 g and isopropanol 80 ml obtained in Production Example 3 were placed in a 100 ml flask, and the atmosphere was 70 in a nitrogen atmosphere. The mixture was heated and stirred at 5 ° C. for 5 hours to obtain a coarse dispersion of an ITO nanoparticle intermediate having malonic acid as a ligand.

  The crude dispersion was repeatedly centrifuged and purified three times using isopropanol to obtain an ITO nanoparticle intermediate precipitate having malonic acid as a ligand. When the obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured, it was found that, compared with 1-hexadecanol which was a ligand before exchange, malonic acid which was a ligand after exchange was 8%. It was confirmed that the ligand exchange proceeded from 1-hexadecanol to malonic acid.

  Next, ITO nanoparticles having malonic acid as a ligand, 278 mg of macrocyclic π-conjugated compound of Exemplified Compound 3-5, and 80 ml of isopropanol were charged into a 100 ml flask, and heated and stirred in a nitrogen atmosphere at 70 ° C. for 150 hours. Thus, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 3-5 as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 3-5.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in isopropanol and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with the exemplary compound 3-5 was 8.9 nm, which is a reaction precursor 1 -Almost no change from 8.9 nm of ITO nanoparticles coordinated with hexadecanol, and it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 3-5 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 3-5 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 450 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle was obtained by planarly coordinating the exemplified compound 3-5, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticle.

  Subsequently, when a part of the obtained ITO nanoparticles were dried to form a nanoparticle powder and the thermogravimetric decrease was measured, the exemplified compound 3-5 as a ligand was coordinated with 7.0% by weight. It was confirmed that there was.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 3-5 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 1.5%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 3-5 exhibit sufficiently high dispersibility in water.

Example 10 (Exemplary Compound 3-3 Coordinated ITO Nanoparticle)
A 100 ml flask was charged with the ITO nanoparticle intermediate coordinated with oleyl alcohol (prepared In + Sn = 1.2 mmol), 1.0 g of citric acid, and 50 ml of N, N-dimethylformamide obtained in Production Example 4 in a nitrogen atmosphere. The mixture was heated and stirred at 80 ° C. for 15 hours to obtain a crude dispersion of ITO nanoparticle intermediate having citric acid as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation using N, N-dimethylformamide three times to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, citric acid as a ligand after exchange was 8.8 times as much as oleyl alcohol as a ligand before exchange. It was confirmed that the ligand exchange proceeded from oleyl alcohol to citric acid.

  Next, ITO nanoparticles having the citric acid as a ligand, 101 mg of the macrocyclic π-conjugated compound of Exemplified Compound 3-3, 50 ml of N, N-dimethylformamide were charged into a 100 ml flask, and 100 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 80 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 3-3 as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and N, N-dimethylformamide as a dispersion solvent to obtain a precipitate of ITO nanoparticles coordinated with Exemplary Compound 3-3.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed with a TEM, the average particle diameter of the ITO nanoparticles coordinated with Exemplified Compound 3-3 was 7.0 nm. Almost no change was observed from 7.1 nm of ITO nanoparticles coordinated with oleyl alcohol, which is a precursor, and it is considered that only the ligand was exchanged.

  Further, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 3-3 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 3-3 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 450 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticle is obtained by planarly coordinating the exemplified compound 3-3, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticle.

  Next, a portion of the obtained ITO nanoparticles were dried to form an ITO nanoparticle powder, and the thermal weight loss was measured. As a result, 8.5% by weight of Exemplified Compound 3-3 as a ligand was coordinated. It was confirmed that.

  In addition, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 3-3 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 0.9%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplified compound 3-3 exhibit sufficiently high dispersibility in water.

Example 11 (Exemplary Compound 4-4 Coordinated ITO Nanoparticle)
An oleyl alcohol coordinated ITO nanoparticle intermediate (charged In + Sn = 1.2 mmol), 1.0 g of citric acid, and 50 ml of isopropanol obtained in Production Example 4 were charged in a 100 ml flask, and 70 ° C. for 12 hours in a nitrogen atmosphere. The mixture was heated and stirred to obtain a coarse dispersion of an ITO nanoparticle intermediate having citric acid as a ligand.

  The crude dispersion was repeatedly centrifuged and purified three times using isopropanol to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, citric acid as a ligand after exchange was 9.0 times as compared with oleyl alcohol as a ligand before exchange. It was confirmed that the ligand exchange proceeded from oleyl alcohol to citric acid.

  Next, ITO nanoparticles having the citric acid as a ligand, 86 mg of the macrocyclic π-conjugated compound of Exemplified Compound 4-4, and 50 ml of isopropanol were charged into a 100 ml flask and heated and stirred at 70 ° C. for 90 hours in a nitrogen atmosphere. Thus, a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 4-4 as a ligand was obtained.

  The crude dispersion was repeatedly purified by centrifugal separation three times using dichloromethane as a precipitation solvent and isopropanol as a dispersion solvent to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 4-4.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in isopropanol and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with the exemplified compound 4-4 was 7.0 nm, and oleyl, which is a reaction precursor, was obtained. Almost no change from 7.1 nm of the alcohol nanoparticles coordinated with ITO, it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 4-4 was observed, and it was confirmed that the present ITO nanoparticles had Exemplified Compound 4-4 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 300 to 400 nm was broadened, and the Q band observed at 600 to 700 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly coordinating Exemplified Compound 4-4, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Next, when a portion of the obtained ITO nanoparticles were dried to form a nanoparticle powder and the thermal weight loss was measured, Example Compound 4-4 as a ligand was coordinated with 8.9% by weight. It was confirmed that there was.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01% by weight of ITO nanoparticles coordinated with Exemplified Compound 4-4 with respect to 100% by weight of water. The solution haze of this dispersion was measured and found to be 3.8%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplary compound 4-4 exhibit sufficiently high dispersibility in water.

Example 12 (Exemplified Compound 3-9 Coordinated ITO Nanoparticle)
A 100 ml flask was charged with the ITO nanoparticle intermediate coordinated with oleyl alcohol (prepared In + Sn = 1.2 mmol), 1.0 g of citric acid, and 50 ml of N, N-dimethylformamide obtained in Production Example 4 in a nitrogen atmosphere. The mixture was heated and stirred at 80 ° C. for 12 hours to obtain a coarse dispersion of an ITO nanoparticle intermediate having citric acid as a coordination ligand.

  The crude dispersion was repeatedly purified by centrifugal separation using N, N-dimethylformamide three times to obtain a precipitate of an ITO nanoparticle intermediate having citric acid as a ligand. The obtained ITO nanoparticle intermediate was dispersed in heavy water and 1H NMR was measured. As a result, the citrate as the ligand after the exchange was 9.2 times the oleyl alcohol as the ligand before the exchange. It was confirmed that the ligand exchange proceeded from oleyl alcohol to citric acid.

  Next, the obtained ITO nanoparticles having citric acid as a ligand, 111 mg of the macrocyclic π-conjugated compound of Exemplified Compound 3-9, and 50 ml of N, N-dimethylformamide were charged into a 100 ml flask and 100 ° C. in a nitrogen atmosphere. The mixture was heated and stirred for 90 hours to obtain a coarse dispersion of ITO nanoparticles having the macrocyclic π-conjugated compound of Exemplary Compound 3-9 as a ligand.

  The crude dispersion was repeatedly purified by centrifugal separation three times using N, N-dimethylformamide to obtain a precipitate of ITO nanoparticles coordinated with Exemplified Compound 3-9.

  Subsequently, when the obtained ITO nanoparticle precipitate was dispersed in N, N-dimethylformamide and observed by TEM, the average particle diameter of the ITO nanoparticles coordinated with the exemplary compound 3-9 was 7.1 nm. Almost no change was observed from 7.1 nm of ITO nanoparticles coordinated with oleyl alcohol, which is a precursor, and it is considered that only the ligand was exchanged.

  Moreover, when a laser Raman spectrum was measured using the same dispersion, a peak equivalent to that of Exemplified Compound 3-9 was observed, and it was confirmed that the ITO nanoparticles had Exemplified Compound 3-9 as a ligand. It was done. Further, when the absorption spectrum of the dispersion at 300 to 800 nm was measured, the Soret band observed at 400 to 450 nm was broadened, and the Q band observed at 500 to 600 nm was hardly confirmed. It was confirmed that the nanoparticles were obtained by planarly aligning Exemplified Compound 3-9, which is a macrocyclic π-conjugated compound, on the surface of the ITO nanoparticles.

  Subsequently, when a part of the obtained ITO nanoparticles were dried to form a nanoparticle powder and the thermogravimetric decrease was measured, exemplary compound 3-9, which is a ligand, was coordinated by 7.7% by weight. It was confirmed that there was.

  Moreover, water was added to the obtained ITO nanoparticles to obtain a dispersion containing 0.01 wt% of ITO nanoparticles coordinated with Exemplified Compound 3-9 with respect to 100 wt% of water. The solution haze of this dispersion was measured and found to be 3.5%. Further, the dispersion was centrifuged at 3,000 rpm for 30 minutes at a rotation radius of 10.1 cm. It was not confirmed. That is, it was confirmed that the ITO nanoparticles coordinated with the exemplified compound 3-9 exhibit sufficiently high dispersibility in water.

Comparative Example 1
9.8 g of Exemplified Compound 2-3 was used in place of 4.5 ml of the hexadecylamine ligand, and Exemplified Compound 2 was prepared in the same manner as in Production Example 2 except that it was not a two-step ligand exchange. Synthesis of -3 coordinated ITO nanoparticles was attempted. Centrifugation was carried out by adding 100 ml of ethanol to the resulting reaction solution, but no precipitate was observed and ITO nanoparticles coordinated with a macrocyclic π-conjugated compound were not obtained.

Comparative Example 2
Into a 100 ml flask were charged ITO nanoparticles coordinated with oleylamine obtained in Production Example 1 (prepared In + Sn = 1.2 mmol), 52 mg of Exemplified Compound 2-5, and 30 ml of isopropanol, and heated and stirred in a nitrogen atmosphere at 80 ° C. for 7 hours. Then, synthesis of Exemplified Compound 2-5 coordinated ITO nanoparticles was attempted (from the oleylamine coordinated ITO nanoparticles as the precursor directly to the macrocycle without passing through the carboxylic acid coordinated ITO nanoparticles as the intermediate Method of ligand exchange to π-conjugated compound). Although 200 mL of dichloromethane was added to the obtained reaction solution and centrifuged, ITO nanoparticles were not precipitated, and ITO nanoparticles coordinated with a macrocyclic π-conjugated compound were not obtained.

  The present invention relates to an ITO nanoparticle having a macrocyclic π-conjugated compound as a ligand, and more specifically, the macrocyclic π-conjugated compound is coordinated in a planar direction with respect to the ITO nanoparticle. The present invention relates to a macrocyclic π-conjugated compound coordinated ITO nanoparticle and a production method thereof. The macrocyclic π-conjugated compound is coordinated in a planar direction with respect to the ITO nanoparticles, and it is expected that specific electrical characteristics that are not obtained with the conventional ITO nanoparticles can be expressed. Since ITO nanoparticles can be mass-produced by a simple technique, it can greatly contribute to the industry.

Claims (1)

It has a carboxylic acid compound as an intermediate by ligand exchange by using ITO nanoparticles having a C6-C24 linear or branched alcohol or amine as a ligand as a precursor. to produce ITO nanoparticles, followed by ligand exchange, a general formula (1) to (4), characterized in that to coordinate the macrocyclic π-conjugated compound, the manufacturing method of I tO nanoparticles.

Wherein R _{1 to} R ₄₈ are each independently a hydrogen atom, a halogen atom, an amino group, a carboxyl group, a thiol group, a hydroxyl group, a linear, branched or cyclic alkyl group having 1 to 10 carbon atoms; A linear, branched or cyclic alkyl group having 1 to 10 carbon atoms having any functional group selected from a group, a carboxyl group, a thiol group and a hydroxyl group; an oxygen atom, a sulfur atom, a carbonyl group in the carbon chain; A C1-C10 linear, branched or cyclic alkyl group containing an ester group, an amide group or an imino group is represented.)