JP4765074B2 - Nanoparticles and method for producing nanoparticles - Google Patents

Description

  The present invention relates to inorganic oxide nanoparticles and a method for producing the same.

  Oxide fine particles and metal oxide particles with nano-order sizes exhibit characteristics different from bulk solids, such as the quantum size effect, so they can be used in a wide range of fields such as energy conversion materials, batteries, catalysts, magnetic materials, and plastic ceramic materials Application in is expected. However, in order to effectively develop the physical properties depending on the size and form of the nano-region, strict form control is required, and various studies have been conducted for the purpose of creating metal oxides having a desired shape and size. Yes.

  For example, Patent Document 1 discloses a method for producing a nano-order sized ceramic three-dimensional structure by a liquid phase deposition method (LPD method), and Patent Document 2 discloses a liquid phase deposition method. A method of forming a ceramic thin film patterned into an arbitrary shape on a substrate is disclosed.

In addition, a method for obtaining metal oxide particles having a nano-order average particle diameter has also been proposed. For example, in Non-Patent Documents 1 to 3, nano-order by a sol-gel method using hydrolysis of metal alkoxide or halide. It has been reported that metal oxide particles having an average particle size can be obtained.
JP 2004-131338 A JP 2004-323946 A Guangshe Li, et al., J. Am. Chem. Soc. 2005, 127, 8659-8666 Markus Niederberger et al., Chem. Commun., 2005, 397-399 Vicki L. Colvin et al., J. Am. Chem. Soc. 1999, 121, 1613-1614

  However, the sol-gel technique as described in Non-Patent Documents 1 to 3 requires a large amount of organic solvent, and is a firing step for obtaining a metal oxide that can satisfy electrical characteristics and the like. Is indispensable and has problems in process and environment. Furthermore, although the metal oxide particles obtained include those having a nano-order particle size, those far exceeding 10 nm are also included, and the particle size distribution is expected to be wide. Is done. In addition, in the synthesis of metal oxides by the sol-gel method, it is difficult to strictly control the particle size.

  The present invention has been made paying attention to the situation as described above, and an object of the present invention is to provide nanoparticles having an average particle diameter of nano-order and a method for producing the same.

With the nanoparticle of the present invention,
(1) Whether the average particle size is 10 nm or less, the coefficient of variation of the particle size is 20% or less, and is made of a metal oxide single crystal,
(2) The average particle size is 10 nm or less, the variation coefficient of the particle size is 20% or less, and is made of silicon dioxide.
However, it has a gist.

  The production method of the present invention is a method for producing the above-mentioned nanoparticles, in which nanoparticles are deposited from a metal fluoride complex aqueous solution or a silicon fluoride complex aqueous solution by a liquid phase deposition method in the presence of a water-soluble compound. It has a gist in place.

  As the water-soluble compound, it is preferable to use a compound having an oxyalkylene group in the main chain and one or two hydroxyl groups (—OH) at the end of the molecular chain. The average molecular weight of the water-soluble compound is It is desirable that it is 100-700. Furthermore, those using polyethylene glycol as the water-soluble compound are recommended embodiments of the present invention.

  Since the nanoparticles of the present invention have a narrow particle size distribution and an average particle size on the order of nanometers, they are expected to be applied to various functional materials such as pigments, catalysts, electronic materials, optical materials, and magnetic materials. The Moreover, it is thought that what consists of a single crystal of a metal oxide among the nanoparticles of this invention can contribute also to the analysis of the characteristic which a nanosized metal oxide particle has. In addition, according to the method of the present invention, particles having a narrow particle size distribution and a nano-order average particle size can be obtained under mild reaction conditions without employing special equipment or complicated reaction steps. it can.

  The present inventors have previously proposed a method of forming various metal oxide thin films on a substrate by a liquid phase deposition (LPD) method. And while tackling such research, the particles obtained by the liquid phase precipitation method in the presence of specific water-soluble compounds have a nano-order average particle size and a very narrow particle size distribution. The present invention has been completed.

[Nanoparticles]
The nanoparticle of the present invention has an average particle diameter of 10 nm or less, a coefficient of variation in particle diameter of 20% or less, and is composed of a metal oxide single crystal or silicon dioxide. It has the characteristics.

Examples of the metal oxide constituting the nanoparticles of the present invention include TiO ₂ , Ta ₂ O ₅ , ZrO ₂ , FeOOH, Fe ₂ O ₃ , ZnO, SnO ₂ , Nb ₂ O ₅ , V ₂ O ₅ , VO ₂ and These oxides include the oxides containing La, Ce, Pr, Nd, Eu, Gd, Tb, and the like as rare earth elements as additive ions. Although not be a single crystal also include SiO ₂ as a material constituting the nanoparticles of the present invention.

The nanoparticles of the present invention have an average particle size of 10 nm or less. An average particle diameter can be changed according to a use, and what has the average particle diameter of the range of 2-10 nm can be obtained by employ | adopting the manufacturing method of this invention mentioned later. Here, the average particle diameter means a value obtained by observing the particle diameters of 2000 particles confirmed from an image taken with a transmission electron microscope (TEM) and calculating by the following calculation method. In addition, the particle | grains observed at this time made all the particle | grains contained in the image | photographed TEM image the measuring object, without performing special selection. The average particle size was the number average particle size. Specifically, as a TEM, a photographed image taken using a high-resolution transmission electron microscope by JEOL JEM-2010 was converted into a TIFF file by a film scanner, and this was further binarized to determine the particle shape. . Then, in the image, each particle diameter (D) was calculated from the following formula by circularly correcting the area S occupied by each particle, and the average particle diameter and the standard deviation were calculated using the values. .
D = 2 (S / π) ^1/2

The nanoparticles of the present invention are all composed of a single crystal (single crystal) except for silicon dioxide (SiO ₂ ). For example, in the case of titanium dioxide (TiO ₂ ), the metal oxide nanoparticles of the present invention are composed of a single crystal of anatase type titanium dioxide. In the case where the nanoparticles of the present invention is made of silicon dioxide (SiO ₂₎ is the nanoparticle becomes amorphous (amorphous) state.

  Furthermore, the nanoparticles of the present invention have a narrow particle size distribution, for example, a coefficient of variation of the particle size of 20% or less. More preferably, it is 12% or less, More preferably, it is 10% or less. The particle diameter variation coefficient is an index of the uniformity of the particle diameter, and it can be said that the smaller the value of the particle diameter variation coefficient, the more uniform the particle diameter. The variation coefficient of the particle diameter is a value measured and calculated by the method described in the examples.

[Production method]
Next, the manufacturing method of the nanoparticle of this invention mentioned above is demonstrated. In the following description, Si is included in the metal for convenience.

  The production method of the present invention is a method for producing the above-mentioned nanoparticle, in the presence of a water-soluble compound, by a liquid phase precipitation method from a metal fluoride complex aqueous solution (or silicon fluoride complex aqueous solution). It is characterized in that it precipitates.

Here, the liquid phase precipitation method uses a hydrolysis equilibrium reaction of a metal fluoride complex. For example, in the hydrolysis reaction system of a metal fluoride complex as shown in the following formula (1), Fluorine ion scavenger (H ₃ BO ₃ ) that takes in F ⁻ ions as a ligand and forms a fluoride complex or compound that is more stable than the starting metal fluoride complex (formula (2)) By adding, the equilibrium reaction of the following formula (1) is moved to the oxide production side to deposit the metal oxide.

  The inventors of the present invention have proposed to form thin films such as metal oxides on various substrates using the above-described reaction, but in the present research, in the presence of a specific water-soluble compound. By carrying out the above reaction, it was found that metal oxide nanoparticles having a nano-order average particle size and a narrow particle size distribution can be obtained at room temperature.

  Although the detailed reason for obtaining the metal oxide nanoparticles having the above-mentioned properties is not clear, due to the intermolecular force acting between the hydrophilic portion contained in the chain structure of the water-soluble compound and the metal fluoride complex, Since the diffusion of the fluoride complex as the reactive species is suppressed and the progress of the hydrolysis equilibrium reaction is limited to the local reaction region, it is considered that the particle growth is suppressed and the nano-size is limited. Further, in this reaction system, a homogeneous reaction field composed of a water-soluble compound solution is formed, so that it is considered that uniform particle diameter and metal oxide particles composed of a single crystal are generated.

As the water-soluble compound, those having an oxyalkylene group in the main chain and having 1 to 2 hydroxyl groups (—OH) at the ends of the molecular chain are preferable. As said alkylene group, a C1-C3 thing is preferable. Specific examples of the oxyalkylene group include polyoxymethylene, polyoxyethylene, polyoxyproprene, polyoxybutylene and the like. Among them, those having an ethylene oxide unit _{([-CH 2 CH 2 O-]} ) are preferred. It is preferable that 3 to 500 ethylene oxide units are contained in the water-soluble compound. More preferably, it is 3-10. In this specification, “water-soluble” is a substance that is compatible with water at room temperature. When a water-soluble compound is dissolved in water (100 g) at 25 ° C. at room temperature, 25% or more is dissolved. It means to do.

  The water-soluble compound preferably has an average molecular weight of 100 to 4000, more preferably 200 to 1000, and still more preferably 200 to 600. If the molecular weight is too large, it becomes a solid at room temperature, and the compatibility with water is not sufficiently maintained. If it is too small, the metal oxide may be difficult to precipitate as particles. The average molecular weight of the water-soluble compound means a value measured by gel permeation chromatography (GPC) using polyacrylic acid as a standard sample, or a notarized value described in a manufacturer's pamphlet or the like. It is.

  Specific examples of the water-soluble compound having the above structure and average molecular weight include polyethylene glycol, polyethylene oxide, and polyethylene glycol mono-p-isooctylphenyl ether (for example, “Triton X—available from Nacalai Tesque, Inc.). 100 (trade name) ") and the like. Among these, polyethylene glycol is preferable, and polyethylene glycol having an average molecular weight of 200 to 600 is particularly preferable.

  The particle diameter of the nanoparticle according to the present invention depends on the amount of the water-soluble compound used. Therefore, the amount of the water-soluble compound used may be appropriately selected according to the desired particle size, particle size distribution, and the like. In addition, when the concentration of the water-soluble compound is too low, the particles may be difficult to precipitate. On the other hand, when the concentration is too high, only fine particles may be generated. Therefore, the concentration of the water-soluble compound is preferably 0.1 to 3M. More preferably, it is 1-2.5M, More preferably, it is 1-1.5M.

Metal fluoride complexes that can be used in the method of the present invention include (NH ₄ ) ₂ TiF ₆ , (NH ₄ ) ₂ TaF ₆ , (NH ₄ ) ₂ ZrF ₆ , (NH ₄ ) ₂ FeF ₆ , and H ₂ SiF _6. , (NH ₄ ) ₂ ZnF ₆ , (NH ₄ ) ₂ SnF ₆ , and the like.

  The concentration of the metal fluoride complex in the reaction solution is preferably 0.1 to 0.5M, more preferably 0.1 to 0.3M, and still more preferably 0.15 to 0.3M. 25M. If the concentration of the metal fluoride complex is too low, it takes a long time to precipitate the particles, whereas if the concentration is too high, the precipitated particles tend to be finer.

Furthermore, in the present invention, a fluorine ion scavenger is used in order to shift the equilibrium of the hydrolysis equilibrium reaction of the metal fluoride complex in the direction in which the oxide is generated. As the fluorine ion scavenger, any of those capable of forming a more stable complex with the fluorine ion as the ligand in the hydrolysis equilibrium reaction represented by the above formula (1) can be used. Boric acid (H ₃ BO ₃ ), aluminum and the like. The amount of these fluorine ion scavengers used is preferably 5 to 30 (molar ratio) (fluorine ion scavenger / metal fluoride complex), more preferably 5 to the metal fluoride complex used as the starting material. -20, more preferably 10-15.

  The solvent is not particularly limited as long as it can dissolve the metal fluoride complex, the water-soluble compound and the fluorine ion scavenger, and water, acetonitrile and the like can be used. Further, if necessary, in addition to the above starting materials and the like, additives for improving doping or precipitation state, precipitation rate, etc., for example, surfactants may be used.

  If the aqueous solution in which the metal fluoride complex, the water-soluble compound and the fluorine ion scavenger are mixed is reacted for a predetermined time with stirring, the nanoparticles of the present invention having monodisperse and nano-order particle diameters can be obtained. It is done. The conditions during the reaction are not particularly limited, and may be adjusted as appropriate while confirming the progress of the reaction. However, it is usually recommended to perform the reaction at 10 to 80 ° C. (more preferably 20 to 40 ° C.) under atmospheric pressure. The Although reaction time is not specifically limited, For example, it is preferable to set it as 5 minutes-20 hours (more preferably 12-20 hours).

  After the completion of the reaction, the produced nanoparticles are separated by centrifugation or the like, washed and dried to obtain monodispersed particles having a nano-order particle size. In addition, the reaction solution separated from the nanoparticles at this time contains unreacted starting materials and water-soluble compounds. Such starting materials are recovered and purified, and then reused as raw materials. can do.

  The obtained nanoparticles may be further subjected to a heat treatment step or the like. At this time, a nitride or a carbide can be obtained by appropriately selecting an atmospheric gas during the heat treatment.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited by the following examples, but may be appropriately modified within a range that can meet the purpose described above and below. It is also possible to implement, and they are all included in the technical scope of the present invention.

[Average particle size, standard deviation, and coefficient of variation of particle size]
The nanoparticle 0.1g obtained by the following experiment example was disperse | distributed by ultrasonic waves in distilled water, and it was dripped on the copper mesh which vapor-deposited carbon, and was dried naturally, and the measurement sample was created. 2000 particles included in a TEM image taken using a high-resolution transmission electron microscope (JEM 2010 manufactured by JEOL Ltd., acceleration voltage: 200 kV) were observed, and the particle size was measured. The particle size is obtained by converting a photographed TEM image into a TIFF file using a film scanner, binarizing the TEM image and determining the particle shape, and then correcting the area S of each particle in the image by circular approximation correction. The particle diameter (D) of each particle was calculated from the following formula, and the standard deviation of the average particle diameter was further measured. Note that the particles observed at this time were all the particles included in the photographed TEM image without special sorting.
D = 2 (S / π) ^1/2

  Further, based on the obtained results, the coefficient of variation (Cv value) of the particle diameter was determined by the following formula. In calculating the coefficient of variation of the particle diameter, all data obtained by measuring the particle diameter are targeted, the standard deviation is calculated from the particle size distribution curve obtained using the least square method, and the obtained value Based on the above, the coefficient of variation was calculated by the following formula.

[Crystal structure]
The crystal structure was confirmed using an X-ray diffractometer (RINT-TTR / S2, manufactured by Rigaku Corporation, Cu-Kα ray, acceleration voltage: 50 kV, current 300 mA). The measurement sample was prepared according to the following procedure.

  The reaction solution containing the generated oxide particles was precipitated at 15000 G using a centrifuge, and the reaction solution was separated and washed by decantation to isolate the oxide particles. This sample was vacuum-dried at room temperature for 72 hours, and the obtained sample was placed on a sample stage of an X-ray diffractometer and measured at 2θ = 10-80 with a θ-θ type goniometer.

Experimental example 1
At room temperature (25 ° C.), in a 50 mL polypropylene reaction vessel equipped with a stirrer, as a water-soluble compound, a 1M concentration polyethylene glycol # 200 (manufactured by Nacalai Tesque, molecular weight of about 200, hereinafter PEG-200) An aqueous solution was added, and (NH ₄ ) ₂ TiF ₆ (Morita Chemical Co., Ltd.) aqueous solution was added so that the concentration in the reaction solution was 20 mM. At this time, the mixed solution was transparent. Next, under stirring of the mixed solution, a 0.5 M boric acid (H ₃ BO ₃ ) aqueous solution 20 (addition amount) was added so that the concentration in the reaction solution was 200 mM. When 10 minutes had passed since the addition of the boric acid aqueous solution, white turbidity of the reaction solution was confirmed. Furthermore, it was made to react at 25 degreeC for 20 hours, stirring. After completion of the reaction, the product was separated from the reaction solution using a centrifuge (15000G), washed and dried to obtain colorless titanium dioxide nanoparticles (about 5 g, yield 50%).

  A TEM image of the produced titanium dioxide particles is shown in FIG. From FIG. 1, it can be seen that the produced titanium dioxide particles have a nano-order particle diameter visually and a substantially uniform particle diameter. In addition, the average particle diameter of the titanium dioxide nanoparticles obtained at this time is 3.8 nm, the variation coefficient of the particle diameter is 10.5% (standard deviation 0.39 nm), and the generated titanium dioxide nanoparticles have a particle size distribution. Was very narrow (FIG. 2).

  Moreover, the high-resolution TEM photograph of the titanium dioxide particle obtained at this time is shown to FIG. 3A and FIG. 3B. The interplanar space of the titanium dioxide particles confirmed from FIG. 3B is consistent with that of the anatase titanium dioxide (112) surface, and a diffraction ring of anatase titanium dioxide was also observed (FIG. 3A). (Upper right figure).

Experimental example 2
The reaction was performed in the same manner as in Experimental Example 1 except that the PEG-200 aqueous solution (water-soluble compound) was not used. Although the reaction was continued at 25 ° C. for 20 hours, the formation of particles was not confirmed, and a thin film-like precipitate was confirmed on the wall surface of the container (FIG. 4).

Experimental example 3
Concentrate 0.1M, 0.2M, 1.1M, 1.7M, 2.4M, 2.8M PEG-200 aqueous solution (water-soluble compound) in a 50 mL capacity polypropylene reaction vessel equipped with a stirrer. In addition, (NH ₄ ) ₂ TiF ₆ aqueous solution was added to each concentration of water-soluble compound solution so that the concentration in the reaction solution was 20 mM. At this time, the mixed solution was transparent.

  Next, 20 mL (addition amount) of an aqueous boric acid solution having a concentration of 0.5 M was added so that the concentration in the reaction solution was 200 mM with stirring of the mixed solution. When 10 minutes had passed since the addition of the boric acid aqueous solution, white turbidity of the reaction solution was confirmed. Furthermore, it was made to react at 25 degreeC for 20 hours, stirring. After completion of the reaction, the reaction solution was centrifuged to separate the product, washed and dried to obtain colorless titanium dioxide particles. FIG. 5 shows the relationship between the particle diameter of the titanium dioxide particles obtained at this time, the coefficient of variation of the particle diameter, and the concentration of the water-soluble compound. In FIG. 5, ◯ represents the average particle diameter, and ● represents the coefficient of variation of the particle diameter.

  As shown in FIG. 5, it can be seen that the average particle diameter of the generated particles increases as the concentration of the water-soluble compound increases. This result shows that the particle diameter of the metal oxide nanoparticles to be generated can be controlled by controlling the concentration of the water-soluble compound. Moreover, even if the average particle diameter of the produced | generated nanoparticle increases, it turns out that the variation coefficient of a particle diameter is about 10%, and a particle size distribution is narrow.

Experimental Example 4
Except that polyethylene glycol # 600 (manufactured by Nacalai Tesque, molecular weight of about 600, hereinafter PEG-600) having a concentration of 0.05M, 0.2M, 0.55M, 0.7M, 0.9M was used as the water-soluble compound. In the same manner as in Experimental Example 3, titanium dioxide particles were produced. FIG. 6 shows a TEM image of titanium dioxide particles obtained in the presence of PEG-600 having a concentration of 0.9 M. The particle diameter of the titanium dioxide particles obtained at this time, the coefficient of variation of the particle diameter, and the concentration of the water-soluble compound. FIG. 7 shows the relationship. In FIG. 7, ◯ represents the average particle diameter, and ● represents the coefficient of variation of the particle diameter.

  6 and 7, even when PEG-600 is used, titanium dioxide particles having a nano-order particle diameter and a narrow particle size distribution are obtained. It can be seen that is effective. Moreover, from FIG. 6, it can confirm that the particle diameter of the metal oxide to produce changes depending on the density | concentration of a water-soluble compound similarly to the case of Experimental example 3 using PEG-200.

Experimental Examples 5-12
A metal fluoride complex aqueous solution shown in Tables 1 and 2 and an aqueous solution containing a metal fluoride complex ion were prepared to produce nanoparticles. The concentrations of the starting material, water-soluble compound and fluorine ion scavenger, and the average particle size, standard deviation and coefficient of variation of the particle size of the obtained metal oxide nanoparticles are shown in Tables 1 and 2 together.

  In addition, the metal fluoride complex aqueous solution used by each experiment example was prepared as follows.

Experimental Example 5: 5 g of SnF ₂ was dissolved in ion-exchanged water, and HF was added until a precipitate oxidized during hydrolysis was dissolved to obtain a Sn / HF reaction solution.

Experimental Example 6: A 1M aqueous solution of (NH ₄ ) ₂ SiF ₆ (Morita Chemical Industries, Ltd.) diluted with ion-exchanged water was used as it was.

Experimental Example 7: 20 ml of 10% ammonia water was added to 5 g of Fe (NO ₃ ) ₂ , and FeOOHg obtained by hydrolysis was redissolved in 100 mL of NH ₄ F-HF aqueous solution to obtain a FeOOH / NH ₄ F-HF solution. . A solution obtained by diluting the obtained solution to 0.1 M was used as a reaction mother liquor.

Experimental Example 8: A reaction mother liquor was prepared by dissolving 7.4 g of powdered Nb ₂ O ₅ in a 1M NH ₄ F-HF solution.

Experimental Example 9: ₅ g of powdered Ta ₂ O ₅ was dissolved in 1 MHF solution, and 1 M was used as a reaction mother liquor.

Experimental Example 10: Zn (OH) ₂ was dissolved in 100 mL of 1M NH ₄ F—HF aqueous solution, and 1M aqueous solution was used as a reaction mother liquor.

Experimental Example 11: Vanadium oxide (V) was dissolved in hydrofluoric acid to prepare a 0.4 mol / l solution with a V ⁵⁺ ion concentration, and ion-exchanged water was added to dilute to 0.15M for reaction. The solution was adjusted.

Experimental Example 12: A reaction solution was prepared by diluting H ₂ ZrF ₆ (Morita Chemical Co., Ltd.) with ion-exchanged water. An aluminum plate (thickness 0.3 mm, 48 cm ² ) was added to the reaction solution as a fluorine scavenger for 50 mL of the reaction solution.

FIG. 8 shows the SnO ₂ nanoparticles obtained in Experimental Example 5, FIG. 9 shows the SiO ₂ nanoparticles obtained in Experimental Example 6, FIG. 10 shows the FeOOH nanoparticles obtained in Experimental Example 7, and FIG. FIG. 11 shows the Nb ₂ O ₅ nanoparticles obtained in Example 1, FIG. 12 shows the Ta ₂ O ₅ nanoparticles obtained in Example 9, and FIG. 13 shows the ZnO nanoparticles obtained in Example 10. FIG. 14 shows the V ₂ O ₅ nanoparticles obtained in No. 11, and FIG. 15 shows the ZrO ₂ nanoparticles obtained in Experimental Example 12. In FIGS. 13 and 15, several relatively large particles appear to exist, but by further increasing the magnification, they are simply present in the proximity of nanoparticles. It is confirmed that it is a thing.

  As is clear from Tables 1 and 2 and the TEM images of FIGS. 8 to 15, in the presence of a specific water-soluble compound, the metal oxide having a uniform nano-order particle size regardless of the type of metal fluoride complex. It can be seen that physical particles can be obtained. Further, in the X-ray diffraction images shown in FIG. 8A, FIG. 9A, and FIG. 10A, spots unique to single crystal diffraction of each generated metal oxide nanoparticle are confirmed, and FIG. FIG. 9C also shows that the metal oxide nanoparticles obtained by the method of the present invention are composed of a single crystal.

  In any of the experimental examples, the nanoparticles could be produced only by stirring the solution in the same manner as the reaction conditions described in Experimental Example 1 and the like without requiring any special attention in the synthesis of the oxide.

  Since the nanoparticles of the present invention have a narrow particle size distribution and an average particle size on the order of nanometers, they are expected to be applied to various functional materials such as pigments, catalysts, electronic materials, optical materials, and magnetic materials. The Moreover, it is thought that what consists of a single crystal of a metal oxide among the nanoparticles of this invention can contribute also to the analysis of the characteristic which a nanosized metal oxide particle has. In addition, according to the method of the present invention, particles having a narrow particle size distribution and a nano-order average particle size can be obtained under mild reaction conditions without employing special equipment or complicated reaction steps. it can.

2 is a TEM image of titanium dioxide particles obtained in Experimental Example 1. FIG. It is a figure which shows the particle diameter and particle diameter distribution of the titanium dioxide particle obtained in Experimental example 1. It shows the results of Experimental Example 1 is a TEM image and X-ray diffraction pattern of the resulting TiO ₂ particles (upper right view of the interior). It is a figure which shows the result of Experimental example 1, and is the TEM image of the particle | grains image | photographed by high resolution TEM. 10 is a TEM image showing the results of Experimental Example 2. It is a graph which shows the result of Experimental example 3, and is a figure which shows the relationship between the average particle diameter of metal oxide particle, and the density | concentration of a water-soluble compound. It is a figure which shows the result of Experimental example 4, and is the TEM image of the obtained metal oxide particle (water-soluble compound density | concentration 0.9M). It is a graph which shows the result of Experimental example 4, and is a figure which shows the relationship between the average particle diameter of metal oxide particle, and the density | concentration of a water-soluble compound. It shows the results of Experimental Example 5 is a TEM image and X-ray diffraction pattern of the resultant SiO ₂ particles (upper right view of the interior). It is a figure which shows the result of Experimental example 5, and is the TEM image of the particle | grains image | photographed by high resolution TEM. It shows the results of Experimental Example 5 is a graph showing the X-ray diffraction results of the obtained SnO ₂ particles. It is a figure which shows the result of Experimental example 5, and is a graph which shows distribution of the particle diameter with respect to the number of particles. Experiment shows the results of example 6 shows a TEM image and X-ray diffraction pattern of the resultant SiO ₂ particles (upper right view of the interior). It is a figure which shows the result of Experimental example 6, and is the TEM image of the particle | grains image | photographed by high resolution TEM. It shows the results of Experimental Example 6 is a graph showing the X-ray diffraction pattern of the resulting SiO ₂ particles. It is a figure which shows the result of Experimental example 6, and is a graph which shows distribution of the particle diameter with respect to the number of particles. It is a figure which shows the result of Experimental example 7, and is the TEM image and X-ray diffraction image (inside upper right figure) of the obtained FeOOH particle. It is a figure which shows the result of Experimental example 7, and is the TEM image of the particle | grains image | photographed by high resolution TEM. It is a figure which shows the result of Experimental example 7, and is a graph which shows distribution of the particle diameter with respect to the number of particles. It shows the results of Experimental Example 8 is a TEM image and X-ray diffraction image of the obtained Nb ₂ O ₅ (upper right view of the interior). It is a figure which shows the result of Experimental example 8, and is the TEM image of the particle | grains image | photographed by high resolution TEM. It is a figure which shows the result of Experimental example 8, and is a graph which shows distribution of the particle diameter with respect to the number of particles. 10 is a TEM image of Ta ₂ O ₅ particles obtained in Experimental Example 9. 10 is a TEM image of ZnO particles obtained in Experimental Example 10. 4 is a TEM image of V ₂ O ₅ particles obtained in Experimental Example 11. 4 is a TEM image of ZrO ₂ particles obtained in Experimental Example 12.

Claims (3)

A method of manufacturing a nano-particles,
Metal fluoride complex aqueous solution or silicon fluoride complex aqueous solution in the presence of a water-soluble compound having an oxyalkylene group in the main chain and one or two hydroxyl groups (—OH) at the ends of the molecular chain From the above , a method for producing nanoparticles comprising depositing nanoparticles by a liquid phase precipitation method without forming reversed phase micelles . The method for producing nanoparticles according to claim 1, wherein the water-soluble compound has an average molecular weight of 100 to 700. The method for producing nanoparticles according to claim 1 or 2 , wherein the water-soluble compound is polyethylene glycol.