WO2004076104A1

WO2004076104A1 - Single-element or multielement metal colloid and method for producing single-element or multielement metal colloid

Info

Publication number: WO2004076104A1
Application number: PCT/JP2004/002354
Authority: WO
Inventors: Naoki Toshima; Yukihide Shiraishi; Hisayoshi Mukai; Toru Matsushita; Mamoru Mizogami
Original assignee: Tanaka Kikinzoku Kogyo K.K.
Priority date: 2003-02-28
Filing date: 2004-02-27
Publication date: 2004-09-10
Also published as: TW200427505A; JP4145166B2; JP2004263222A; TWI314475B

Abstract

A single-element or multielement metal colloid comprising nanoparticles composed of one or more of metal species and one or more kinds of protective agent for protecting the nanoparticles is characterized in that the protective agent is composed of a low molecular weight material which has one or more electrostatic groups and a molecular weight of 30-5,000. The electrostatic groups contained in the protective agent may preferably be carboxyl groups, amino groups, sulfo groups, phosphoric acid groups, silicic acid groups, or boric acid groups.

Description

Specification

Field of the Invention Uni- or multi-component metal colloids and methods for producing mono- or multi-component metal colloids

The present invention relates to a mono- or multi-component metal colloid solution and a method for producing the same. Background art

Metal colloid refers to a state in which fine particles (nanoparticles) of 1 to 100 nm insoluble in a solvent or a ceramic or the like are dispersed or suspended in a solvent. A colloid using a liquid as a solvent is referred to as a metal colloid. Solutions are generally known. Here, the term “nanoparticles” refers to not a single atom but a nano-order group consisting of two, three, or more atoms. In recent years, application of metal colloids to the production of materials in various fields such as catalysts, optical, electric, and magnetic materials has been studied.

Colloids are considered to be useful in the production of various materials, but one of the areas where they are expected to be used is as catalysts for fuel cell catalysts, automotive exhaust gas treatment catalysts, and other catalysts. Applications are listed. This is because the nanoparticles constituting the colloid can be supported on the carrier as catalyst particles. It is thought that the catalyst supporting the nanoparticles exhibits a different reaction behavior from the conventional catalyst supporting the atomic or molecular metal. It is expected that catalysts using colloid will find better properties in future studies.

Another reason that colloids are effective for the production of catalysts is that multiple types of metal atoms are aggregated as nanoparticles in colloids, which makes multi-component metal catalysts, especially multi-component metal Can easily produce an alloyed catalyst. For example, used in automobiles In recent years, binary platinum-Z rhodium catalysts have been used in exhaust gas treatment catalysts. This is because by arranging rhodium particles near platinum particles having a catalytic action, it is possible to suppress the movement and the growth of platinum particles that may occur during the use of the exhaust gas treatment catalyst. For fuel cell catalysts, the use of platinum-Z-ruthenium binary catalysts is promising. This is achieved by arranging hydrophilic ruthenium in the vicinity of the platinum particles and alloying them, thereby oxidizing and removing carbon monoxide, which is the OH_ bonded to ruthenium, adsorbed on the platinum. This is because catalyst poisoning by carbon monoxide can be prevented.

Incidentally, metal colloids generally contain a compound called a protective agent. A protective agent is a compound that chemically or physically binds and adsorbs around nanoparticles in metal colloid.It suppresses aggregation of nanoparticles and controls the particle size distribution to an appropriate range to stabilize it. It means something that causes it. In other words, by adding a protective agent, nanoparticles with a fine particle size are kept suspended, and in the production of catalysts, the particle size of the catalyst particles is reduced to increase the effective surface area of the catalyst as much as possible. Will be able to The present inventors studied the stability of platinum / rhodium colloid to which polyvinylpyrrolidone (hereinafter referred to as PVP) was added as a protective agent, and confirmed that this colloid solution was stable for a long time. . Furthermore, when this colloid solution was adsorbed using alumina powder as a carrier to produce an exhaust gas purifying catalyst, this exhaust gas purifying catalyst was stable without any grain growth even in a high-temperature oxidizing atmosphere. (Refer to Japanese Patent Application Laid-Open No. 2000-27978 and Japanese Patent Application Laid-Open No. 2000-279798). However, it has become clear that conventional colloids have good adsorbability to powder carriers, but have a problem that they are not easily adsorbed to ceramic-coated (posh-coated) honeycomb carriers. When a catalyst is produced using a colloid solution with a low adsorption rate, not only a catalyst with insufficient activity is produced but also the production efficiency of the catalyst is reduced. It will be.

The present invention has been made under the above background, and an object of the present invention is to provide a colloid containing a protective agent, which has good adsorbability regardless of the type of carrier. Disclosure of the invention

The present inventors examined the cause of the difference in the adsorptivity depending on the type of the carrier in the conventional colloid, and found that it was due to the relationship between the pore size of the carrier and the entire size of the nanoparticle including the protective agent. Reached the conclusion. That is, since the nanoparticles are suspended in the metal colloid while being surrounded by the protective agent (hereinafter, a combination of the nanoparticles and the surrounding protective agent is referred to as a colloid particle). The pores into which colloid particles can enter are pores having a diameter larger than the size of the protective agent. On the other hand, the diameter of the pores differs depending on the type of the carrier, the pores of the powder carrier are relatively large, and the ceramic-coated carrier is dense and has a small pore diameter. Therefore, in the case of the conventional colloid, the colloid particles can penetrate into the pores in the powder carrier, but cannot penetrate into the pores in the ceramic coat carrier, so that the adsorptivity is poor. It is.

The present inventors believe that it is necessary to obtain a colloid composed of colloid particles having a size that can penetrate into micropores as a colloid having an adsorptivity to a ceramic-coated carrier. Was. Here, the protective agent applied to the conventional colloid is mainly a polymer material such as PVP, and it can be said that the size of the colloid particles also increases. Therefore, the present inventors set the molecular weight of the protective agent to an appropriate range in order to control the size of the colloid particles, and thereby obtain a colloid composed of colloid particles that can penetrate into micropores. I decided.

That is, the present invention provides a mono- or multi-component metal colloid comprising nanoparticles composed of one or more metal species, and one or more protective agents that protect the nanoparticles, Has one or more electrostatic groups A mono- or multi-component metal colloid characterized by being a low molecular weight material having a molecular weight of 30 to 500.

The present invention reduces the size of the colloid particles by using a low-molecular material as the protective agent, allows the colloid particles to penetrate into fine pores, and enables adsorption to a carrier having such pores. Here, the molecular weight of the protective agent must be in the range of 30 to 500,000 in order to obtain a colloid having the properties intended by the present invention. If it is more than 500, the size of the whole colloid particles becomes large, and it is difficult to penetrate into the fine pores.

In addition, the colloid protective agent according to the present invention needs to have at least one or more electrostatic groups. An electrostatic group is a functional group that behaves as an anion or a cation in a solvent. As described above, the protective agent also has the purpose of preventing the nanoparticles from agglomerating and coarsening, but in the present invention, the requirement for the electrostatic group is to achieve this purpose more effectively. It is. In other words, when the protective agent has an electrostatic group, a repulsive force is generated between the protective agents, and the aggregation of the nanoparticles can be suppressed.

As the electrostatic group of this protective agent, any of a carboxyl group, an amino group, a sulfo group, a phosphoric acid group, a kaic acid group and a boric acid group is preferable. Further, it is preferable that the number of electrostatic groups contained in the protective agent is large, from the viewpoint of repulsion, and it is preferable that the protective agent has two or more electrostatic groups.

Specific examples of the protective agent suitable for the present invention that satisfies the above-mentioned conditions of low molecular weight and the presence of an electrostatic group include citric acid, phosphoric acid, tartaric acid, succinic acid, polyphosphoric acid, heteropolyacid, and caicic acid , Boric acid, N- (2-acetamide) iminoniacetic acid, acetylenedicarboxylic acid, amino acid, N-acetylglycine, N-acetyl-L-lysine, adipic acid, oxalic acid, maleic acid, ethylenediaminetetraacetic acid, 2-amino-2-methylbutadionic acid, 2-amino-4-methylpentanedioic acid, 8-T minnow 1-naphthol-1,3,6-disulfonic acid, aspartic acid, azelaic acid,

1, 2, 3-benzenebenzenecarboxylic acid, butylmalonic acid, pantothene Acid, phorphoric acid, N-lipobenzyloxy L-aspartic acid, S-carboxymethyl-L-cystine, citramalic acid, citrazic acid, 1,1-cyclohexanediacetic acid, 1,2-cyclohexanediamin-N , N, N ', N'-tetraacetic acid, 1,2-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, diethylenetriaminepentaacetic acid, benzoyltartaric acid, 2,2-dimethyldartaric acid, 2 , 4-Dimethyldaltaric acid, 3,3-dimethylglutaric acid, phthalic acid, terephthalic acid, glutaric acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,2,1-dithiodiacetic acid, 5, 5, 1-dithiobis' (2-dibenzobenzoic acid), benzoic acid, 2, 2'-dithiosalicylic acid, salicylic acid, ethylenedioxybis (ethylamine) _ N, N, Ν ,, Ν '— Tetraacetic acid, glutamic acid, hexafluoroglutaric acid, η —' (2-hydroxine tinole) ethylenedinitrile triacetate, 5-hydroxysisophthalic acid, isoftanoleic acid, maleic acid, malic acid , Malonic acid, mercaptosuccinic acid, Ν-methyliminodiacetic acid, mucinic acid, 3-nitrophthalic acid, oxal acetic acid, 2,2'-monoxydiacetic acid, pimelic acid, 2-ketoglutaric acid, tri-triacetic acid, 5- Sulfosalicylic acid, acid of taurine, or alkali metal salt or ammonium salt of these acids, or 1,1'-b2-naphthol, 4,4-biphe-nolesionore, ,, Ν'bis aminoethyl) one 1, ₃ one Puropanjiamin, New, Nyu- bis (3-Aminopuropiru) Mechiruamin, sebacic acid bis (2-Etokishechi Le), sebacic acid (2-ethylhexyl), 2,2-bis (hydroxymethyl) 1,2,2,2 ', 12 tri-mouth Triethanol, biurea, 1,3-butanediol, 1,2-butanediol , 1,4-butanediol. The protective agent in the metal colloid may be used alone or may contain a plurality of protective agents.

Further, the protective agent preferably has a reducing action. As described below, the metal colloid according to the present invention is produced by dissolving a metal salt in a solvent once and reducing metal ions in the solvent to nanoparticles, but the protective agent is In the case of having a reducing action, nanoparticles can be obtained by adding a protective agent to a solvent without using a reducing agent as a solvent, and the process of colloid production can be simplified. Suitable protective agents having a reducing action in the present invention include sodium kuninate, sodium borohydride, N-methylpyrrolidone, oxalate, EDTA and sodium salt, and the like.

The metal species constituting the nanoparticles is not particularly limited. However, considering the use of the metal colloid according to the present invention, platinum, palladium, silver, gold, noretenium, rhodium, iridium, osmium, iron, copanoleto , Nickel, copper, and indium are preferred. The metal species is manganese, aluminum, molybdenum, tungsten, barium, cerium, zirconium, titanium, vanadium, niobium, tantalum, rhenium, sub-, germanium, tin, antimony, bismuth, boron, and neodymium. You may comprise. The metal colloid nanoparticles according to the present invention may be composed of only one kind of metal as described above, or may be a plurality of metal species aggregated.

In the method for producing a colloid according to the present invention, the precious metal salt is reduced by mixing a noble metal salt and water or a mixed solvent of water and an organic solvent and a protective agent, and adding a reducing agent to the solution. It is preferable to use colloid particles. Regarding the reduction of noble metal salts in solution, a method of electrochemical reduction by inserting an electrode into the solution and conducting electricity is also applicable, but a method by adding a reducing agent enables uniform reduction treatment. . In addition, in the case of the electrochemical reduction, the power source, electrodes, and the control device for reducing the solution, and the equipment configuration for producing the colloid solution are complicated, and the current required for performing the appropriate reduction is reduced. Also, it is difficult to set voltage conditions and the like. In the case where the protective agent has a reducing action, colloid can be produced by mixing the metal salt and the protective agent with a solvent without adding a reducing agent.

The reducing agents added here are sodium borohydride, hydrazine, Dimethylaminoborane and trimethylamineborane are preferred. These reducing agents are preferred because they have strong reducing power and can be reduced in a short time.

When the above-described protective agent having a reducing action is used as the protective agent, the protective agent may be used as the reducing agent, and only the protective agent may be added, but both the reducing agent and the protective agent may be used. It may be added. When a reducing agent and a protective agent are added, a part of the protective agent also acts as a reducing agent, and the remaining protective agent functions as a protective agent for the reduced nanoparticles.

Further, a solvent having a reducing action may be used. Examples of the solvent in this case include dimethylformamide, ethanol, methanol, propanol, and tetrahydrofuran.

When a protective agent or a solvent having a reducing action is used, reduction of the metal ion can be achieved even if the amount of the reducing agent added is small (equivalent to the metal salt or less). In the method according to the present invention, the amount of the reducing agent added is preferably in the range of 1/500 equivalent to 10 equivalent of the metal salt.

The metal salts used as raw materials include metal salts for the production of platinum colloids, such as hexacloplatinic acid, dinitrodiammineplatinum, dinitrodiammineplatinum nitrate, cis-diamminediaquaplatinum nitrate, Trans-diammine diaqua platinum nitrate, tetra nitroplatinate, tetra (oxalate) platinate, cis-dinitrodiaqua platinum, tetraamine platinum hydrate, hexammine platinum hydroxide, tetraamine platinum chloride, Hexammine platinum chloride, hexahydroxyplatinic acid, platinum oxide, platinum (l) chloride, platinum (l) chloride, potassium tetraplatate can be applied.

The metal salts used in the production of palladium colloids include palladium chloride, tetranitropalladium acid, palladium nitrate, dichlorodiammine palladium, tetraamminepalladium nitrate, tetraammine palladium chloride, tetraamminepalladium Hydrochloride, Trans-Aquaasianminbaladium nitrate, Dinitrodiammaminebaladium, Bis (ethylene diammine) ^ radium nitrate, diaqua (ethylene diammine) palladium nitrate are applicable.

The metal salts used in the production of gold colloids include chloroauric acid, potassium gold (II) cyanide, gold potassium cyanide, gold nitrate tetraammonium, gold ammonium nitrate tetra-trate, diaqua (1) , 10-phenanthone lin) Gold nitrate can be applied.

As a metal salt for producing silver colloid, silver chlorate, silver nitrate, silver acetate, and silver lactate can be used.

The metal salts used in the production of ruthenium colloid include ruthenium chloride, ruthenium nitrate, tetra-trosyldiaquaruthenium, ruthenium acetate, hexaammine ruthenium nitrate, pentaamminequaruthenium nitrate, and nitrosyl pentane Phanmine ruthenium nitrate and hydroxonitrosyltetraammine ruthenium nitrate are applicable. Metal salts used in the production of rhodium colloid include rhodium chloride, rhodium nitrate, rhodium acetate, pentaammine aqua rhodium nitrate, pentaammine aqua rhodium nitrate, pentaammine nitrolodium, triaqua rhodium nitrate, and hexammine aqua. Rhodium nitrate can be applied.

Metal salts used in the production of iridium colloid include hexaclo iridic acid, iridium trichloride, hexanitroiridic acid, tris (oxalato) iridium acid, pentaammine aqua iridium nitrate, Nitropentaammine iridium nitrite and hexaammine iridium nitrate can be applied.

Osmium oxide can be used as a metal salt for producing osmium colloid.

As a metal salt for producing iron colloid, iron chloride, iron nitrate, iron fumarate, iron dalconate, iron oxalate, iron sulfate, and iron carbonyl can be applied. '' Metal salts for the production of copartoid colloids include cobalt chloride, cobalt fumarate, cobalt hydroxide, cobalt nitrate, and cobalt sulfate. Baltic, cobalt power ponil can be applied. Nickel acetate, nickel acetyl acetate, dihydrate, nickel bromide, nickel chloride, nickel hydroxide, nickel nitrate, nickel sulfate can be used as metal salts for the production of nickel colloid. . As a metal salt for producing indium colloid, indium chloride, indium hydroxide, indium nitrate, indium phosphate, and indium sulfate can be applied. We also manufacture colloids of molybdenum, tungsten, barium, cerium, zirconium, titanium, vanadium, niobium, tantalum, rhenium, zinc, genolemanium, tin, antimony, bismuth, boron and nejidium. For these, chlorides, nitrates, and sulfates of these metal species can be applied as metal salts.

In the method according to the present invention, both one-dimensional colloids and multi-dimensional colloids can be produced. In the case of producing a multi-component colloid, a plurality of metal salts to be dissolved in a solvent are dissolved, and a plurality of metal ions in the solution are reduced simultaneously or sequentially to form a plurality of metal ions. Colloids containing nanoparticles composed of metal species can be produced.

In the case of producing a multi-element metal colloid, a plurality of single-element metal colloids may be separately produced and mixed. That is, a plurality of metal colloids containing nanoparticles composed of different metal species may be produced by the above method, and the produced metal colloids may be mixed to form a composite metal species. Here, the term “composite” refers to a structure in which a plurality of metal species are randomly mixed, a state in which a plurality of metal species are regularly arranged and mixed, or a case in which one metal forms a center and another metal forms a center. Also include a bandage that forms a multilayer structure covering it. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a diagram showing a change in silver concentration when a carrier was immersed in a metal colloid of the first embodiment and Comparative Example 1. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, preferred embodiments of the present invention will be described together with comparative examples.

First Embodiment: 1. a silver perchlorate solution 2 mL of 6 6 X 1 0- ² M in water, and Kuen acid sodium solution 0.2 of 3. 4 X 1 0 _ ² M as coercive Mamoruzai It is added and stirred, which was obtained in 5 0 mL of the silver colloids solution 1. 6 5 X 1 0- ² M borohydride sodium was added 0. 0 5 mL as the reducing agent. Second Embodiment 3. and 8 8 X 1 0- ² M rhodium solution 0. 8 7 mL chloride in water, and 3.4 Kuen acid X 1 0- ² M sodium © beam solution 2 mL as protectant is added and stirred, which was obtained in 1. 6 5 X 1 0- ² M borohydride sodium © arm was added 1 mL with 5 O mL of rhodium colloids solution as the reducing agent. Comparative Example 1: 0.14676 g of PVP was taken at R = 40, 3 mL of water was added under a nitrogen stream, and the mixture was stirred for 10 minutes. After stirring, and stirred further for 30 minutes in addition 2 mL 1. 6 6 X 1 0- 2 M perchloric silver solution. Then, 45 mL of ethanol was added as a reducing agent, and the ratio of water: ethanol was 1: 9. This was refluxed at 90 to 95 ° C for 2 hours to obtain a silver colloid solution. Comparative Example 2: 0.14776 g of PVP was taken at R = 40, and 4.13 mL of water was added under a nitrogen stream, followed by stirring for 10 minutes. After stirring, and stirred further for 30 minutes in addition 0. 8 7 mL rhodium chloride solution 3. 8 0 X 1 0 one ² M. Then, 45 mL of ethanol was added thereto as a reducing agent, and water: ethanol was adjusted to 1: 9. This was refluxed at 90 to 95 ° C. for 2 hours to obtain a rhodium colloid solution. With respect to the silver colloid produced in the first embodiment 'and the comparative example 1, the adsorption speed on the carrier (ceramic coating layer on the honeycomb) was measured. In the adsorption test, 150 mL of each colloid and aqueous solution diluted with water until the silver concentration reached 5 ppm was taken, and this was coated with alumina on a metal carrier (alumina amount: 2.85 g). Was immersed. Then, while stirring the solution, the solution was sampled at regular intervals, and the platinum concentration was measured by inductively coupled plasma emission spectroscopy (ICP).

FIG. 1 shows the change in silver concentration of each solution when the carrier was immersed. From this figure, it can be seen that the rate of decrease in silver concentration (ie, silver adsorption rate) when the silver colloid according to the first embodiment was adsorbed was higher than that of Comparative Example 1, and it took about 4 hours. It was confirmed that the adsorption was completed and the adsorption was performed in a shorter time than in the comparative example.

Claims

The scope of the claims

1. A mono- or multi-component metal colloid comprising one or two or more kinds of metal species and one or more kinds of protective agents for protecting the nanoparticles,

A mono- or multi-component metal colloid, wherein the protective agent is a low molecular weight material having a molecular weight of 30 to 500 and having one or more electrostatic groups.

2. The mono- or multi-component electrostatic group contained in the protective agent is any one of a carboxyl group, an amino group, a sulfo group, a phosphoric acid group, a keic acid group and a boric acid group. Metal colloid.

3. Protecting agents include cunic acid, phosphoric acid, tartaric acid, succinic acid, polyphosphoric acid, heteropolyacid, caicic acid, boric acid, N- (2-acetamide) iminoniacetic acid, acetylenedicarboxylic acid, and amino acid , N-acetylglycine, N-acetyl-L-lysine, adipic acid, oxalic acid, maleic acid, ethylenediaminetetraacetic acid, 2-amino-2-methylbutadionic acid, 2-amino-4-methylpentanedionic acid , 8-amino-1-naphthol-1,3,6-disulfonic acid, aspartic acid, azelineic acid, 1,2,3-benzenetricarboxylic acid, petit / remalonic acid, pantothenic acid, camphoric acid, N-carbo Benzoxy L-aspartic acid, S-carboxymethyl-l-cysteine, citramalic acid, citrazinic acid, 1,1-cyclohexanediacetic acid, 1,2- Chlohexanediamine mono N, N, N ,, N'-tetraacetic acid, 1,2-cyclohexanedicanoleponic acid, 1,4-cyclohexanedicarboxylic acid, diethylenetriaminepentaacetic acid, benzoyltartaric acid, 2,2 —Dimethyldaltaric acid, 2,4-dimethyldaltaric acid, 3,3-dimethyldaltaric acid, phthalic acid, terephthalic acid, glutaric acid, 2,2-dimethylsuccinic acid, 2,3-dimethylsuccinic acid, 2,2'-dithionic acetic acid, 5,5'-dithiobis (2-nitrobenzoic acid), benzoic acid, 2,2'-dithiosalicylic acid, salicylic acid, ethylenedioxybis (ethylamine) N, N, N ,, N '—Tetraacetic acid, glutamic acid, hexafluorologuric acid, n— (2-hydroxyshethyl) ethylenedinitrotriacetic acid, 5-hydroxyisophthalic acid, isophthalanolic acid, maleic acid, lingic acid , Malonic acid, mercaptosuccinic acid, N-methyliminodiacetic acid, mucinic acid, 3-ditrophthalic acid, oxalacetic acid, 2,2'-monoxydiacetic acid, pimelic acid, 2-ketoglutaric acid, Acetic acid, 5-sulfosalicylic acid, acids of taurine, or alkali metal salts or ammonium salts of these acids, or 1,1'-B2-naphthol, 4,4-biphenyldiol N, N'-bis (2-aminoethyl) 1-1,3_propanediamine, N, N-bis (3-aminopropyl) methinoleamine, bis (2-ethoxyxetil) sebacate, bis (2 sebacate) —Ethylhexyl), 2,2-bis (hydroxymethyl) 1,2,2,2 ′, 12 Triethanol, Piurea, 1,3 Butanediol / re, 1,2 Butane diol, 1, 4 one Butanjio single-component according to claim 1 or claim 2 wherein the le or multi-component metal colloid _t

4. The mono- or multi-component metal colloid according to claim 1, wherein at least one of the protective agents has a reducing ability.

5. The single system according to claim 4, wherein at least one of the protective agents is sodium citrate, sodium borohydride, N-methylpyrrolidone, oxalate, EDTA / ninatodium salt. Multi-component metal colloid.

6. The single or multiple element according to claim 1, wherein the metal species is one of platinum, palladium, silver, gold, ruthenium, rhodium, iridium, osmium, iron, cobalt, nickel, copper, and indium. Metal colloid.

7. Metal species are any of manganese, aluminum, molybdenum, tandatin, barium, cerium, zirconium, titanium, vanadium, niop, tantazole, rhenium, zinc oxide, genolemanium, tin, antimony, bismuth, boron, and neodymium. The mono- or multi-component metal colloid according to claim 1, wherein

8. A method for producing a mono- or multi-component metal colloid according to claims 1 to 7, wherein

Dissolving one or more metal salts and one or more protective agents in a solvent to produce a solution in which the metal ion is dispersed in the solvent,

A method for producing a mono- or multi-component metal colloid, in which a reducing agent is added to the solution to reduce the metal ions into nanoparticles.

9. The mono-or multi-component system according to claim 8, wherein at least one of the protective agents is sodium tenoate, sodium borohydride, N-methylpyrrolidone, oxalate, or EDTA / nina-triformate. Manufacturing method of metal colloid.

10. The method for producing a mono- or multi-component metal colloid according to claim 8 or 9, wherein the reducing agent is sodium borohydride, hydrazine, dimethylaminoborane, or trimethylamineborane.

11. The method according to claim 8, wherein the solvent is dimethylformamide, ethanol, methanol, propanol, or tetrahydrofuran.

12. The mono- or multi-component metal colloid according to any one of claims 8 to 11, wherein the metal ion is reduced by adding a reducing agent in an amount of 1/500 to 10 times equivalent to the metal salt. Manufacturing method.

13. A plurality of metal colloids containing nanoparticles composed of different metal species are produced by the method according to claims 8 to 12, and the produced metal colloids are mixed to mix the metal species. Method for producing multi-component metal colloids into converted nanoparticles.