JP2010502540A - How to make nanoparticles - Google Patents

Abstract

The present invention provides a method for producing Group IV element nanoparticles, preferably Si, Ge and Sn, and binary and ternary alloy nanoparticles of these elements. In the method of the present invention, one or more Group IV metal precursors are decomposed in the solution phase using a decomposition accelerator at an elevated temperature, in an inert atmosphere, and at atmospheric pressure. For example. A surface binder is added to the reaction mixture to form an organic layer that covers the nanoparticles and prevents aggregation.
[Selection] Figure 1

Description

  The present invention relates to a method for producing Group IV element nanoparticles. In particular, it relates to the production of nanoparticles of Si, Ge and Sn, and binary and ternary alloys of these elements.

  The present invention relates to quantum dots, and quantum dots are known as nanoparticles or nanocrystals.

  The term “nanoparticle” is generally referred to to refer to particles having an average diameter of about 1 nm to about 100 nm. Nanoparticles have intermediate sizes between individual atoms and macroscopic bulk solids. Nanoparticles having a diameter smaller than or equivalent to the exciton Bohr radius of the material can exhibit quantum confinement effects. Depending on the effect, the optical properties, electrical properties, catalytic properties, optoelectronic properties, thermal properties and magnetic properties of the material may change.

  Many nanoparticles exhibit a very large photoluminescence effect compared to that observed in macroscopic crystals having the same composition. Furthermore, these quantum confinement effects can be altered by changing the size of the nanoparticles and the surface chemistry. For example, there are size-dependent discrete optical and electronic transitions for nanoparticles of Group II-VI semiconductors (eg, CdSe) and Group III-V semiconductors (eg, InP).

  Vapor phase synthesis of Group IV nanoparticles by processes such as metal organic chemical vapor deposition (MOCVD) is well known. However, such methods have low yields and require large capital. The liquid phase synthesis techniques used in the synthesis of Group II-VI and Group III-V semiconductors have not been successfully applied to Group IV materials, which are mainly based on highly crystalline nanostructures. This is due to the high temperature required to produce the particles in high yield. The strong covalent bonding of amorphous Si and Ge means that the synthesis is significantly higher than the synthesis temperature used in Group II-IV materials to increase core crystallinity at a commercially viable production rate. Means temperature is needed. Moreover, the temperature required to thermally decompose many of the liquid phase Group IV precursors exceeds the boiling point of many typical solvents at atmospheric pressure.

  There have been few reports of solution phase reduction of group IV salts and aerosol methods. However, many of the nanoparticles produced by these methods have a very wide size distribution and very low visible luminescence efficiency.

  Where this specification refers to external sources of information, including patent specifications and other documents, this is generally intended to provide a context for discussing features of the present invention. To do. Unless otherwise stated, citations of such sources are interpreted as approving that in any trial, such sources are prior art or form part of the common general knowledge in the art. Should not be done.

  Provides a method for producing nanoparticles that replaces currently available methods for producing nanoparticles and / or provides a method for producing nanoparticles that produce good monodisperse and / or highly luminescent nanoparticles. can do.

  In a first aspect, the present invention comprises heating at atmospheric pressure under an inert atmosphere to bring one or more Group IV metal precursors into a liquid reaction medium comprising a high temperature surfactant. A method for producing nanoparticles of one or more Group IV metals or alloys thereof comprising the steps of reacting with a decomposition accelerator, adding a surface binder, and recovering the nanoparticles I will provide a.

  In one aspect, the liquid reaction medium may include a hot solvent and a hot surfactant.

In a preferred embodiment, the Group IV metal precursor has the general formula G (Ar) _x Y _4-x , where G is a Group IV metal, Ar is aryl, Y is halo, and x is at least 0 and takes a value of 4 or less).

In another embodiment, the Group IV metal precursor has the general formula G (Ar) _y Y _2-y , wherein G is a Group IV metal, Ar is aryl, and Y is halo; And y is at least 0 and takes a value of 2 or less).

Preferably, the decomposition accelerator is
a) Strong reducing agent or b) S, Se, Te, P or As, or a compound composed of one or more of these zero-valent elements.

  In one aspect, the method of the present invention includes the additional step of adding a quenching agent prior to adding the surface binder. Preferably, the step of adding a quenching agent is before adding the surface binder but after adding the degradation accelerator.

  In a preferred embodiment, the decomposition accelerator is selected from the group consisting of S, Se, Te, P and As, and compounds containing one or more of these zero-valent (see below) elements. And the method includes adding a quenching agent.

  In one aspect, the surface binder can also act as a quenching agent.

  Preferably, the step of adding a surface binder is effective to prevent nanoparticle aggregation. Preferably, the surface binding agent interacts with the nanoparticles and produces an organic layer surrounding the nanoparticles.

  In preferred embodiments, the surface binding agent is a carboxylic acid, aldehyde, amide, or alcohol. More preferably, the surface binder is a carboxylic acid, so that the resulting nanoparticles are “acid terminated”.

  In other preferred embodiments, the surface binder comprises an alkenyl moiety or an alkynyl moiety.

  Accordingly, one preferred embodiment of the present invention involves the production of acid-terminated nanoparticles of one or more Group IV metals, or alloys thereof. Preferably, it includes the production of nanoparticles terminated with acid in Ge, Si or Sn, or binary or ternary alloys of these elements.

  Preferably, the step of reacting is heated to a temperature of about 100 ° C to about 400 ° C, more preferably heated to a temperature of about 200 ° C to about 400 ° C, more preferably a temperature of about 300 ° C. Including that.

  Preferably, the method of the present invention is completed in less than 30 minutes. More preferably, the method is completed in less than about 20 minutes.

  Preferably, the method includes an additional step of purifying the nanoparticles.

  Preferably, the method produces nanoparticles in the range of about 1 nm to about 20 nm, more preferably in the range of about 1 nm to about 10 nm.

  Preferably, the method provides a monodisperse nanoparticle size distribution such that the standard deviation of the nanoparticle diameter is less than 20% of the average diameter. More preferably, the method provides a monodisperse nanoparticle size distribution such that the standard deviation of the nanoparticle diameter is less than 5% of the average diameter.

Preferably, the present method, a larger concentration than 1GL ^-1, more preferably made nanoparticles solution of greater concentration than 10GL ^-1.

  Preferably, the method produces nanoparticles with a chemical reaction yield greater than 50%, more preferably greater than 60%.

  Preferably, the method produces nanoparticles that produce luminescence in response to photoexcitation having a quantum efficiency of greater than 1%. More preferably, nanoparticles are produced that produce luminescence in response to photoexcitation with quantum efficiencies greater than 20%.

  Preferably, the method produces nanoparticles with high crystallinity. In a preferred embodiment, G is germanium and the crystal structure is substantially a diamond structure.

  In an additional aspect, the present invention provides Group IV metal or Group IV metal alloy nanoparticles substantially made by the methods of the present invention.

In addition, in an additional aspect, the present invention provides nanoparticles terminated with hydrogen in one or more Group IV metals or alloys thereof having the general formula L-R-N, where R is Alkyl, alkenyl, or aryl, L is a group having the desired functionality, and N is a functional group that can bind to the surface of the hydrogen-terminated nanoparticle). And a method of producing chemically functionalized nanoparticles in one or more Group IV metals or alloys thereof comprising the steps of: and recovering chemically functionalized nanoparticles provide. Suitable N _{groups, -NH 2, -COOH, -CONH 2} , -CONH 2, -OH, -CHO, -SO 3 H, -PO 3 H 2, -PH 2, -SH, -CH = CH ₂ , —C≡CH, —Cl, —F, —Br, and —I.

Preferably, the chemically functionalized nanoparticles are made by reacting hydrogen-terminated nanoparticles with a compound of the formula LRN (where L is a polar functional group). Water-soluble nanoparticles. According to another embodiment, the hydrogen-terminated nanoparticles are of the LRN formula, where L is a functional group capable of binding to biochemical antibodies and / or biochemically active molecules. Biochemically functionalized nanoparticles that are reacted with a compound of Suitable L _{groups, -NH 2, -COOH, -CONH 2} , -CONH 2, -OH, -CHO, -SO 3 H, -PO 3 H 2, -PH 2, -SH, -CH = CH ₂ , —C≡CH, —Cl, —F, —Br, and —I.

  In another aspect, the present invention provides chemically functionalized nanoparticles composed of one or more Group IV metals or their alloys made by the methods of the present invention.

  In another aspect, the present invention provides hydrogen terminated nanoparticles of one or more Group IV metals, or alloys thereof, preferably Ge, Si, or Sn, or two components thereof An alloy, or a ternary alloy thereof, is a method for producing hydrogen-terminated nanoparticles, wherein the nanoparticles of the present invention terminated with acid, aldehyde, alcohol or amide are hydrogenated in the absence of moisture and oxygen. A method is provided that includes reacting with a fluoride reducing agent and recovering hydrogen-terminated nanoparticles.

  In a preferred embodiment, hydrogen terminated nanoparticles are made from the nanoparticles of the present invention terminated with acid.

  In another aspect, the present invention provides nanoparticles terminated with hydrogen of one or more Group IV metals or their alloys made substantially by the method of the present invention.

  The nanoparticles of the present invention are suitable for mixing into a matrix of secondary materials such as polymeric materials, ceramic materials, metallic materials or other materials. Furthermore, the present invention is suitable for manufacturing elements such as photovoltaic elements and photoelectric elements including biochemical imaging elements.

  Other aspects of the invention will become apparent from the following description, given by way of example only and with reference to the accompanying drawings.

  As used herein, the term “aryl” is intended to include optionally substituted aromatic groups and optionally substituted heterocyclic aromatic groups. This aromatic group includes, but is not limited to, phenyl, naphthyl, indanyl, biphenyl, and the like. Optionally substituted heterocyclic aromatic groups include, but are not limited to, pyrimidinyl, pyridyl, pyrrolyl, furyl, oxazolyl, thiophenyl, and the like.

  As used herein, the term “alkyl” is intended to include optionally substituted straight chain hydrocarbon groups, branched chain hydrocarbon groups, and saturated cyclic hydrocarbon groups.

  As used herein, the term “alkenyl” is intended to include optionally substituted straight chain hydrocarbon groups, branched chain hydrocarbon groups, and monounsaturated cyclic hydrocarbon groups.

  As used herein, the term “alkynyl” is intended to include optionally substituted straight and branched chain hydrocarbon groups containing a —C≡C— moiety. .

  As used herein, the term “halo” refers to an iodo, chloro, bromo or fluoro group.

  Where a particular compound is a compound comprising one or more alkyl, alkenyl, alkynyl, aryl or halo, each such group can be independently selected.

  As used herein, the term “optionally substituted” refers to one or more in a group provided that the valence of each atom to which the optional substituent is attached does not exceed the normal valence. It is intended to mean that two or more hydrogen atoms are replaced with one or more suitable substituents selected independently.

  As used herein, the terms “nanoparticle”, “nanocrystal”, and “quantum dot” refer to any particle that is less than 100 nanometers in size.

  Although “nanocrystals” can have a higher degree of crystallinity than nanoparticles, references herein to nanoparticles are understood by those skilled in the art to include nanocrystals and quantum dots. Should be.

  As used herein, the “size” of a nanoparticle refers to the diameter of the core of the nanoparticle. The nanoparticles generally comprise one or more cores of a first material and can optionally be covered by a shell of a second material.

  The nanoparticles of the present invention generally comprise a “core” of a Group IV metal (silicon, germanium, tin, etc.), or alloys of these metals, optionally coated on a “shell” of a second material. Can be done. The term “core” refers to the central region of the nanoparticle. The core can comprise a substantially single homogeneous material. The core may be crystalline, polyatomic, or amorphous. Although the core can be crystalline, it is understood that the surface of the core may be amorphous or polycrystalline, and this amorphous surface layer may extend toward the interior of the core at a finite depth. It is understood. A “shell” of nanoparticles may include one layer of organic or inorganic, two layers including both an inner inorganic layer and an outer organic layer, and vice versa. May be included. The shell material can be selected to minimize the number of “dangling bonds” at the surface of the nanoparticle core. The nanoparticle shell material of the present invention is generally determined by the surface binder used in the method of the present invention.

  As used herein, the term “photoluminescence” in a nanoparticle refers to the emission of a first wavelength (wavelength range) by the nanoparticle after emission of a second wavelength (wavelength range). The first wavelength (wavelength range) is longer than the second wavelength (wavelength range).

  As used herein, the term “quantum efficiency” refers to the ratio of the number of photons emitted by a nanoparticle to the number of photons absorbed by the nanoparticle.

  As used herein, the term “monodisperse” with respect to nanoparticles means that at least 75%, preferably 100% (or an integer or non-integer therebetween) of the population of nanoparticles falls within a particular particle size range. Refers to a population of nanoparticles. The population of “monodisperse” particles has a standard deviation of less than 20% of the mean diameter, and the “highly monodisperse” population has a standard deviation of less than 5% of the mean diameter.

  As used herein, the term “surfactant molecule” refers to a molecule comprising a nonpolar end and a polar end. This nonpolar end includes an alkyl group, an alkynyl group or an aryl group, or a combination thereof. The polar ends include various acids such as carboxylic acids, sulfinic acids, sulfonic acids, phosphinic acids and phosphonic acids and their salts, as well as primary, secondary, tertiary or quaternary amines, halogens One or more groups selected from chlorides, oxides, sulfides, thiols, phosphines, phosphorus compounds, phosphates and glycols.

  As used herein, the term “degradation promoter” is a compound that promotes a chemical reaction that includes a precursor compound of a Group IV metal at a given temperature such that one or more Group IV metals are formed. Or refers to the material.

  As used herein, the term “and / or” means “and”, “or”, and both “and” and “or”.

  As used herein, “(s)” after a noun means the plural and / or singular of the noun.

  As used herein, the term “comprising” means “consisting of at least a portion of”. When interpreting the description in this specification and the claims that include that term, all requirements that precede that term in each statement or claim must exist, but other requirements also exist be able to. Related terms such as “include” and “include” should be interpreted similarly.

  References to numerical ranges disclosed herein (for example, 1 nm to 10 nm with respect to nanoparticle size) refer to all integer and non-integer references within the range (eg, 1, 1.1, 2 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9, and 10) and any range of integers and non-integers within that range (eg, 2-8, 1.. 5 to 5.5, 3.1 to 4.7).

  The present invention also includes parts, elements and requirements, as well as combinations of any of the parts, elements or requirements mentioned or shown individually or collectively in the specification of the present application. In the specification of the present application, it is to be noted that each specific finished product is recognized as equivalent in the technology related to the present invention. Are considered to be included in the specification of the present application.

The invention will now be described by way of example with reference to the following drawings in which:
FIG. 1 is a general flow diagram of the method of the present invention. FIG. 2 is a flow diagram of one aspect of the method of the present invention. FIG. 3 is a flow diagram of another aspect of the method of the present invention. FIG. 4a is a transmission electron micrograph of germanium nanoparticles prepared according to the present invention. FIG. 4b is another transmission electron micrograph of germanium nanoparticles made according to the present invention. FIG. 5 is X-ray diffraction data of germanium nanoparticles prepared according to the present invention. FIG. 6 shows electron diffraction of germanium nanoparticles prepared according to the present invention. FIG. 7 shows the luminescence spectrum of germanium nanoparticles made according to the present invention. FIG. 8 is a diagram of a typical glass device useful in the method of the present invention. FIG. 9a shows a chemically functionalized nanoparticle with an organic surface layer made according to the present invention. FIG. 9b shows a hydrogen-terminated nanoparticle made according to the present invention. FIG. 9c shows a carboxylic acid group attached to the surface of an acid terminated nanoparticle made according to the present invention.

  The present invention relates to a method for producing nanoparticles containing one or more Group IV elements. In a preferred embodiment, the method includes forming nanoparticles comprising a semiconductor material composed of one or more elements of Si, Ge, and Sn.

  The method includes reacting one or more Group IV metal precursors in a liquid reaction medium using a decomposition accelerator under an inert atmosphere at atmospheric pressure. The reaction is carried out by heating the reaction mixture. In a preferred embodiment, the Group IV metal precursor is a raw material for a semiconductor material composed of one or more of Si, Ge and Sn.

  Generally speaking, the degradation accelerator may be a reducing agent, a polymerizing agent, or other suitable substance. Further, the method includes the use of a high temperature surfactant in the reaction mixture. The method includes the addition of a strong interaction surface binder to the reaction mixture. This surface binder forms an organic coating on the nanoparticles and prevents aggregation of the nanoparticles during subsequent crystal growth.

  A general method for producing nanoparticles will be described with reference to FIG.

As shown in FIG. 1, the inventive method includes the four steps listed below.
(A) heating a solution comprising a liquid reaction medium and one or more Group IV metal precursors at atmospheric pressure under an inert atmosphere;
(B) introducing a decomposition accelerator to promote the decomposition of the precursor of the Group IV metal.
(C) optionally introducing a quenching agent to remove excess degradation promoter. This optional step is not necessary, for example, if there is no excess degradation accelerator, and may not be required if the degradation accelerator is a reducing agent (as discussed below).
(D) introducing a surface binder to prevent aggregation of the resulting nanoparticles.

  Each of these steps will be discussed in detail below.

-Group IV metal precursors-
Many Group IV metal precursors are suitable for use in the method of the present invention. These include organometallic compounds containing silicon atoms, germanium atoms, or tin atoms. Preferably, these organometallic compounds containing silicon, germanium or tin atoms have the following molecular formula G (Ar) _x Y _4-x , wherein G is a Group IV metal, Ar is aryl, Y Is a halo, and x is at least 0 and takes a value of 4 or less).

  Such compounds include tetraphenyl germanium, triphenylchlorogermanium, diphenyldichlorogermanium, phenyltrichlorogermanium, tetraphenylsilane, triphenylchlorosilane, diphenyldichlorosilane, phenyltrichlorosilane, tetraphenyltin, triphenylchlorotin, diphenyl Included are dichlorotin, phenyltrichlorotin or their analogous compounds in bromine, iodine or fluorine. However, it is not limited to these.

Alternatively, the precursor species of the Group IV metal include molecular formula G (Ar) _y Y _{2-y where} G is a Group IV metal, Ar is aryl, Y is halo, and y is at least 0. Group IV atoms that are divalently bonded to the aryl group and halide compound.

  In a preferred embodiment, Ar is optionally substituted phenyl, more preferably phenyl.

In a preferred embodiment, the Group IV precursor is a phenyl-substituted precursor, G (Ph) _x Y _4-x . When the decomposition accelerator is selected from the group consisting of S, Se, Te, P and As and a compound composed of one or more elements of these zero-valent states (see below), This precursor is particularly preferred.

  The Group IV precursor may be a mixture of different Group IV precursors including precursors having different Group IV metals. This can result in the formation of an interface in the alloy or final nanoparticles.

-Liquid reaction medium-
The primary role of the liquid reaction medium is to solvate the Group IV metal precursor and various reagents to ensure a homogeneous liquid phase reaction. The liquid reaction medium also provides a barrier to the aggregation of the nanoparticles due to the interaction between the surface of the high temperature surfactant nanoparticles. These treatments are effective for making the size of the nanoparticles highly monodisperse.

  One skilled in the art will appreciate that the liquid reaction medium must be thermally stable at the reaction temperature.

  In one aspect, the liquid reaction medium includes a hot surfactant and a hot solvent. Alternatively, the high temperature surfactant also acts as a high temperature solvent.

  As used herein, the term “high temperature” means that the surfactant or solvent should be thermally stable at the reaction temperature under an inert atmosphere and have a boiling point above the reaction temperature. means.

  The reaction temperature is preferably about 100 ° C to about 400 ° C, more preferably about 200 ° C to about 400 ° C, and more preferably about 300 ° C.

  The surfactant has a molecular structure containing functional groups that can interact with the surface of the nanoparticles. This acts to form a thin layer of solvent material that binds weakly to the surface of the nanoparticles. In this way, aggregation of the nanoparticles can be prevented. Preferred surfactants do not participate in parasitic side reactions with reactants and precursors.

Suitable surfactants that meet the above criteria include R—NH ₂ , R—PH ₂ , R ₃ N, R ₃ P, R ₂ NH, R ₂ PH, R ₄ N ⁺ , and RE _y (wherein , R is alkyl, alkenyl or aryl, E is an ethylene glycol group, and N, P and H have their usual meanings in the International Union of Pure and Applied Chemistry) It is not limited to the compound of.

  Preferred high temperature surfactants include oleylamine, hexadecylamine, trioctylamine and trioctylphosphine. These surfactants act as coordinating solvents so that no additional solvent is required.

  In those embodiments where the liquid reaction medium includes a high temperature surfactant and a high temperature solvent, suitable high boiling organic solvents include alkanes, alkenes, aromatic hydrocarbons and other paraffins, mono- or poly-ethylene glycol ethers. , Crown ethers, and phenyl ethers, but are not limited to these.

  The Group IV metal precursor can be introduced into the liquid reaction medium before or after the liquid reaction medium is heated to the reaction temperature. In a preferred embodiment, the liquid reaction medium is flowed with a suitable inert gas to purge gaseous contaminants from the reaction vessel prior to introducing the Group IV metal precursor and other reactants. Heat to desired reaction temperature.

  Suitable inert gases are known to those skilled in the art. Such gases include, but are not limited to nitrogen, argon, and helium. Preferably, the inert gas is nitrogen.

  If the precursor is relatively chemically stable, there is no need to carry out the reaction in a controlled atmosphere glove box and a simple Schlenk line or similar gas purge glass apparatus can be used. FIG. 8 shows a typical bench top glass apparatus suitable for this synthesis. A liquid reaction medium 1 is placed in a three-necked round bottom flask 2. The temperature is monitored using a thermometer probe 3 covered with a protective glass enclosure 4. The solution is stirred with a magnetic stir bar 5 and heated 6 with a heating mantle, hot bath, or similar device. An inert gas is introduced into the flask 2 through the gas inlet 7 and discharged through the exhaust port 10. The reagent can be added to the flask 2 using an injector temporarily inserted into the gas inlet 7. Furthermore, the condenser 8 is used to cool and condense the vapor on the medium surface of the liquid reaction medium 1. The condenser can be water-cooled with water passing through the outer glass sheath through the water inlet 9 and the drain outlet 9.

  While it is possible to heat the reaction mixture to reaction temperature during step b), usually the reaction mixture is heated to reaction temperature during step a).

-Decomposition accelerator-
After degassing, a decomposition promoter is added to the solution of the Group IV metal precursor in the liquid reaction medium, generally under heated and inert atmosphere conditions.

  The decomposition accelerator may be injected into the reaction vessel in solution or in suspension. In a preferred embodiment, the decomposition accelerator may be added as a liquid carrier solution which is the same as the solution constituting the liquid reaction medium.

  Decomposition promoters promote the decomposition of the group IV metal precursors, generally Ge, Si or Sn (or alloys thereof) into elemental forms as nanoparticles at the reaction temperature at the reaction temperature. The general reaction scheme is as follows.

ここで、ｎｐはナノ粒子形成物を示す。

Here, np represents a nanoparticle formed product.

  In one embodiment of the present invention, as shown in FIG. 2, the decomposition accelerator is a strong reducing agent. The decomposition accelerator must be capable of cleaving a substituent-Ge bond, a substituent-Si bond, or a substituent-Sn bond.

  In embodiments where the Group IV metal precursor is a phenyl metal compound, the degradation promoter must be capable of cleaving one or more Si-Ph bonds, Sn-Ph bonds, or Ge-Ph bonds. It has long been assumed that this strong covalent bond is stable to reductive action. However, the liquid phase method disclosed herein uses a combination of a high reaction temperature and a strong reducing agent, so that from a precursor having a Si-Ph bond, a Sn-Ph bond, or a Ge-Ph bond. Obtain elemental Group IV metal.

  Examples of strong reducing agents include sodium borohydride, lithium borohydride, potassium borohydride, sodium naphthalenide, sodium anthraside, lithium naphthalenide, lithium anthraside, potassium naphthalenide, potassium anthraside, hydrogen Lithium aluminum hydride, sodium aluminum hydride, potassium aluminum hydride, sodium hydride, lithium hydride, potassium hydride, sodium, lithium, potassium, sodium sulfide, lithium sulfide, potassium sulfide, tin dichloride, tin dioleate, two One or more of tin bromide, tin diiodide, sodium amide, sodium azide and triphenylphosphine are included. However, it is not limited to these.

  In another aspect of the invention, as shown in FIG. 3, the degradation promoter is one or more elements in group V or group VI, or one or more of these zero-valent states. Includes compounds with elements. Here, the one or more group IV elements or group VI elements are selected from the group comprising sulfur, selenium, tellurium, phosphorus and arsenic.

In a preferred embodiment, the degradation accelerator comprises S or Se (or a compound having one of these elements in the zero valence state). For this example embodiment where the Group IV metal precursor is (Ph) ₃ GeCl, the general reaction scheme is shown below.

ここで、ｎｐはナノ粒子形成物を示す。

Here, np represents a nanoparticle formed product.

In an embodiment in which the degradation accelerator includes S (or a compound having S in the zero valence state), by-products include Ph—S—Ph, Ph—Cl, Ph, Ph—Ph, Cl ₂ , S, and GeS _2. May be included.

-Quenching agent-
In the embodiment of the invention shown in FIG. 3, a quenching agent is generally used. However, a quenching agent may be used in an embodiment in which the decomposition accelerator is a strong reducing agent.

  The quenching agent acts to remove excess decomposition accelerator from the reaction mixture. Therefore, the effect of suppressing the growth of nanoparticles possessed by the decomposition accelerator is removed. Furthermore, the use of a quenching agent prevents excessive reaction of the surface accelerating agent added to the reaction mixture after the quenching agent in some embodiments and the decomposition accelerator.

  When the decomposition accelerator is selected from the group consisting of S, Se, Te, P, As and a compound containing one or more of these elements in the zero-valent state, a quenching agent is added after decomposition of the precursor. It is preferable to add.

In a preferred embodiment,
a) a strong reducing agent or
b) S, Se, Te, P or As, or a decomposition accelerator is selected from one of these elements having one or more of these elements in the zero-valent state, and the quenching agent is a non-aqueous high boiling point It is an acid. Suitable non-aqueous high boiling acids include, but are not limited to, carboxylic acids and compounds having one or more carboxylic acid groups.

  In another aspect, the decomposition accelerator is selected from the group consisting of S, Se, Te, P, As, and compounds containing one or more of these elements in the zero-valent state, and the quenching agent Hydride reduction such as sodium borohydride, lithium borohydride, potassium borohydride, lithium aluminum hydride, sodium aluminum hydride, potassium aluminum hydride, sodium hydride, lithium hydride, or potassium hydride Can be an agent.

-Surface binder-
A surface binder is added to the reaction mixture to prevent nanoparticle aggregation. The surface binder can provide a stronger interaction for the nanoparticles than that obtained from the high temperature surfactant in the liquid reaction medium. Generally, the surface binder is added in excess.

  Advantageously, by adding a surface binder after the initial degradation of the precursor, parasitic side reactions of the surface binder with the degradation promoter can be prevented. The second motivation to add a strong binding surface binder after the initial degradation of the precursor is that the binding between the nanoparticles and the surface binder is so strong that it can inhibit the growth of the nanoparticles. It is. Nevertheless, it is possible to add a surface binder to the reaction mixture prior to or simultaneously with the addition of the degradation accelerator.

  In embodiments where the degradation accelerator is a strong reducing agent, suitable surface binders that are susceptible to reduction as a parasitic side reaction include trioctyl phosphine oxide, carboxylic acid, sulfonic acid, phosphonic acid, alcohol, thiol, and others But not limited to these proton donor compounds.

  Generation of a parasitic side reaction in the case where a decomposition accelerator is selected from the group consisting of S, Se, Te, P, As, and compounds containing one or more of these elements in the zero-valent state. Suitable surface binders that may be susceptible to reduction include, but are not limited to, primary phosphines, secondary phosphines, and tertiary phosphines.

  Advantageously, in embodiments where the surface binder comprises an alkenyl moiety or an alkynyl moiety, the surface binder forms a stable bond between the Group IV metal and carbon at the surface of the nanoparticle. Can do.

  In other embodiments, the surface binder is of the general formula RN, wherein R is alkyl, alkenyl or aryl, and N is a functional group capable of binding to the surface of the Group IV metal nanoparticles. A).

  In addition, the surface binder is represented by the general formula L—R—N, wherein R is alkyl, alkenyl or aryl, L is a functional group having a desired function, and N is a group IV metal nano A functional group capable of binding to the particle surface).

In a preferred embodiment, L and _{N, -NH 2, -COOH, -CONH 2} , -OH, -CHO, -SO 3 H, -PO 3 H 2, -PH 2, -SH, -CH = CH 2, Each is independently selected from the group comprising —C≡CH, —Cl, —F, —Br, and —I.

  In a preferred embodiment, the surface binder is the same as the quenching agent. In this embodiment, if the surface binder is in excess, excess degradation promoter is removed from the reaction mixture.

  After the addition of the surface binder, the nanoparticles remain in the suspension. The nanoparticles generally enter the purification / recovery step.

-Recovery and purification of nanoparticles-
After producing the nanoparticles by the method disclosed above, the nanoparticles are collected and optionally purified. Recovery and purification can be accomplished by a number of techniques known to those skilled in the art. Such techniques include, but are not limited to, nanoparticle flocculation and centrifugation, or two-phase separation methods that appropriately select an immiscible solvent.

An example of a purification procedure, which is only an example, is as follows.
(A) Add a flocculant to the reaction mixture.
(B) Centrifugation of the mixture aggregated at a rotational acceleration exceeding 1000 G.
(C) The supernatant is removed and processed.
(D) Resuspension is performed in an organic solvent having a boiling point lower than about 120 ° C. (low boiling point solvent). And optionally,
(E) Repeat steps (a) to (d) until the required purity is obtained.

  Suitable flocculants include, but are not limited to, distilled water or appropriately purified water, and alcohols including methanol, ethanol, propanol and butanol, methylformamide and acetone.

  Suitable low boiling point media include, but are not limited to, toluene, tetrahydrofuran (THF), chloroform, dichloromethane and liquid alkanes having less than 10 carbon atoms.

-Characterization of nanoparticles-
By the method of the present invention, nanoparticles and / or nanocrystals of Group IV metals or their alloys are formed. The nanoparticles are firm, chemically stable, can be crystalline, and can be coated with an organic passivation layer or an inorganic passivation layer.

  In the present specification, the product according to the method of the present invention has been described for nanoparticles or nanocrystals. However, those skilled in the art will recognize that the Group IV metal nanoparticles have a coating layer, and the composition of the coating layer is a surface binder. You will see that it depends. For example, if the surface binder is oleic acid, the oleic acid binds to the surface as shown in FIGS. 9a and 9c.

  FIG. 9a shows a group IV metal nanoparticle core 70 having a surface binder 71, which can be a carboxylic acid, such as oleic acid, to form an organic surface layer. FIG. 9b is a diagram of hydrogen terminated Group IV metal nanoparticles prepared according to one embodiment of the present invention. FIG. 9c shows a carboxylic acid group as present in oleic acid, which is attached to the surface of the Group IV metal nanoparticles.

Other general examples of functional groups capable of binding to a Group IV metal surface of _{nanoparticles, -NH 2, -COOH, -CONH 2} , -OH, -CHO, -SO 3 H, -PO 3 H 2, _{-PH 2, -SH, -CH = CH} 2, -C≡CH, -Cl, -F, -Br, include -I, and -H.

-Additional steps-
-Nanoparticles with hydrogen termination-
In many potential applications in Group IV metal nanoparticles, it is advantageous to be able to chemically functionalize the nanoparticles by adding specific molecules to the surface of the nanoparticles. Therefore, it is important to obtain a clean crystal face that is not functionalized so that the functionalization reaction can proceed therefrom. Of particular interest is the crystal plane with hydrogen ends as shown in FIG. 9b.

  An additional aspect of the present invention is the use of Group IV metal nanoparticles terminated with acids, from Group IV metal nanoparticles terminated with acids, aldehydes, alcohols or amides, grown outside the glove box environment. It is production.

  In a preferred embodiment, nanoparticles terminated with hydrogen are made from nanoparticles terminated with acid.

This aspect is achieved by the following method shown as an example.
(A) A mixture of purified Group IV metal nanoparticles terminated with an acid, aldehyde, alcohol or amide in a solvent at or below the boiling point of the solvent at an atmospheric pressure and under an inert atmosphere. And a hydrogen reducing agent is added.
(B) The resulting mixture is reacted for up to 48 hours in the absence of moisture and oxygen.
(C) Quench the reaction.

  Suitable hydrogen reducing agents include lithium aluminum hydride, sodium aluminum hydride, potassium aluminum hydride, lithium triethyl borohydride, sodium triethyl borohydride, sodium borohydride, lithium borohydride, potassium borohydride, Examples include, but are not limited to, hydrogen gas, sodium hydride, potassium hydride, lithium hydride, borane-tetrahydrofuran complex, lithium tri-tert-butoxyl aluminum hydride, sodium cyanoborohydride and diisobutylaluminum hydride.

  Suitable inert gases are those known to those skilled in the art. Such inert gases include, but are not limited to nitrogen, argon and helium. The inert gas is preferably nitrogen.

  In a preferred embodiment, the reaction is quenched with alcohol. Suitable alcohols include but are not limited to methanol, ethanol, butanol and propanol.

-Chemical functionalization-
In an additional aspect of the present invention, chemically functionalized Group IV metal nanoparticles are produced by reacting the surface of the hydrogen terminated nanoparticles of the present invention with certain chemically active species.

The chemically active species is of the general formula L—R—N, wherein R is alkyl, alkenyl or aryl, L is a functional group having the desired function, and N is a hydrogen-terminated group IV. A functional group capable of binding to the surface of the metal nanoparticles). Such functional _{groups, -NH 2, -COOH, -CONH 2} , -OH, -CHO, -Cl, -F, -Br, -I, -PO 2 H, -PH 2, -SH, - SO ₃ H, —CH═CH ₂ and —C≡CH are included, but are not limited to these.

In one specific embodiment of the present invention, a hydrogen-terminated nanoparticle is represented by the general formula L-RN (where L is a polar functional group) and is reacted with a compound to react with water. Nanoparticles can be produced. In another aspect, the hydrogen-terminated nanoparticles are of the general formula L-R-N, where L is a functional group capable of binding to biochemical antibodies and / or biochemically active molecules. Biochemically functionalized nanoparticles can be made by reacting with a compound represented by: Here, suitable L groups include —NH ₂ , —COOH, —CONH ₂ , —OH, —CHO, —SO ₃ H, —PO ₃ H ₂ , —PH ₂ , —SH, —CH═CH _2. , -C≡CH, -Cl, -F, -Br and -I.

-Preferred characteristics-
In preferred embodiments, the methods and resulting nanoparticles of the present invention incorporate a number of favorable properties.

-Relative ease of production-
Advantageously, the method of the present invention may be performed at a draft chamber or bench top location. On the other hand, many of the prior art methods require the use of a high pressure and / or controlled atmosphere glove box technique or other protective environment. This is because the method of the present invention is performed at atmospheric pressure and uses relatively mild or harmless reagents compared to many of the prior art methods.

  Accordingly, a preferred embodiment of the method of the present invention uses a common glass apparatus that is run at atmospheric pressure and purged with an inert gas. Such a device is illustrated in FIG.

-High yield-
By the methods described herein, high reaction yields of nanoparticles exceeding 60% can be achieved. Such yields can be achieved using non-hydride decomposers, thereby preventing the formation of volatile by-products, silanes, germanes, stannanes and their derivatives. In this method, the group IV element of the precursor species remains in the reaction vessel until the reaction is complete. The reaction is terminated at the solid-phase nanoparticles, and the elemental particles crystallize from the reaction solution, thereby ensuring a decomposition reaction that proceeds to completion.

  One skilled in the art understands that the presence of a chemical species that binds to the surface of the nanoparticle increases the yield of the nanoparticle, but it is difficult to confirm the yield with some accuracy. The yield figures obtained here are the yields from the synthesis in the absence of quenching agent, surfactant or surface active material.

-Relatively high throughput-
In a preferred embodiment of the invention, the reaction time is short, generally less than 1 hour, more preferably less than 30 minutes. In addition, nanoparticles can be synthesized at a solution concentration greater than 2 gl ^−1, and in a more preferred embodiment, nanoparticles can be synthesized at a concentration greater than 10 gl ⁻¹ . Such production rates are significantly improved compared to many of the prior art processes.

-Good monodispersion-
4a and 4b show transmission electron microscope (TEM) images of germanium nanoparticles produced by the method of the present invention. The scale bar for both photos is 20 nm. It can be seen that it is highly monodisperse. This is achieved by the homogeneous nature of the reaction solvent phase.

  FIG. 5 shows X-ray diffraction data of germanium nanoparticles produced by the method of the present invention, indicating high crystallinity of the nanoparticles. The copper peak observed in the X-ray diffraction data is due to the TEM grid bar. In a preferred embodiment of the invention, nanoparticles having a diameter standard deviation of less than 20% of the average diameter are made, and in a more preferred embodiment, nanoparticles having a diameter standard deviation of less than 5% of the average diameter are made.

  FIG. 6 shows an electron diffraction pattern of 8 nm germanium nanoparticles prepared by the method of the present invention.

-Spectral characteristics-
In one embodiment, the nanoparticles of the present invention emit colored light of a wavelength in the visible spectrum in the photoexcited state. In other embodiments, the nanoparticles emit light in the near-infrared and infrared wavelengths with short wavelengths relative to the band gap of the bulk crystalline material in the photoexcited state. The wavelength of the light emitted from the nanoparticles can be varied through manipulation of the size of the nanoparticles, the chemical structure of the passivation layer, and the chemical composition of the Group IV metal or alloy comprising the nanoparticles. In one aspect, the methods disclosed herein produce passivated germanium nanoparticles that exhibit discrete optical transitions and photoluminescence. FIG. 7 shows the typical (as a function of excitation wavelength) luminescence of a solution of germanium nanoparticles. Preferred embodiments in the method of the present invention produce nanoparticles with a luminescence with a quantum efficiency of more than 1%, more preferably up to 20% and more than 20%.

-Use-
The nanoparticles of the present invention have many possible uses, as will be appreciated by those skilled in the art.

  The nanoparticles of the present invention are observed to emit in the visible spectrum and can be used in the field of biochemical imaging or as starting materials for new optoelectronic devices. Group IV nanoparticles are of particular interest in the field of biochemical imaging because the long-lived, stable and low toxicity of germanium, silicon and tin is very attractive compared to today's alternatives .

  The nanoparticles of the present invention can be incorporated into biochemical imaging markers. For such applications, the average particle size of the nanoparticles can be from about 1 angstrom to about 200 angstroms, resulting in nearly monochromatic luminescence in the visible spectrum in response to photoexcitation. The biochemical imaging system can include a linker that attaches the biochemically active molecule to the nanoparticle, allowing for the tagging of specific compounds. The biochemical imaging system can have more than one type of linker, with each type of linker connecting to nanoparticles that emit at different wavelengths with a substantially monochromatic visible wavelength.

  The nanoparticles of the present invention can be incorporated into optoelectronic materials by a variety of methods including thin film deposition of nanoparticles on a substrate. The nanoparticles can include, for example, silicon or germanium or a compound thereof. For such applications, the average particle size of the nanoparticles can be from about 1 angstrom to about 200 angstroms. The deposited nanoparticles can be fired at a temperature of about 300 ° C. to 900 ° C. to produce a thin film of material exhibiting optoelectronic properties. In some embodiments, the thin film can be composed of a plurality of nanoparticles, resulting in other crystalline materials. This material can be further used to manufacture various electronic devices including photovoltaic devices, infrared light emitting devices and light emitting devices.

  Another aspect of the optoelectronic material can include mixing one or more nanoparticles in a matrix of one or more macromolecular species so that the electrons are transmitted by external electronic contacts. It can move from nanoparticle to nanoparticle. The nanoparticles can include silicon or magnesium or alloys thereof. At least one of the nanoparticles can have an average particle size of about 1 nm to about 20 nm. The nanoparticle mixed matrix can be formed on a substrate or a flexible film. This material can be further used to make various electronic devices including photovoltaic devices, infrared light emitting devices and light emitting devices.

  The nanoparticles of the present invention can be incorporated into photovoltaic devices that generate power from light and near infrared radiation. The device can include a plurality of nanoparticles. The photovoltaic element can have electrical contacts at the anode and the cathode. The photovoltaic device can include nanoparticles of a size optimized for maximum absorption of the incident solar spectrum.

  Various aspects of the invention will now be described in a non-limiting manner with reference to the following examples.

Example 1
1) Put 4.5 g hexadecylamine (HAD) or 7.5 ml oleylamine into a three neck round bottom flask.
2) Add 0.05 g of triphenylchlorogermanium to the flask.
3) Place the flask in a stirred heating mantle under a cold water condenser and a nitrogen purge stream.
4) Heat to 285 ° C to 300 ° C with stirring.
5) Inject a solution of 0.005 g of sulfur in 1.5 ml of trioctylamine.
6) Wait about 5 minutes.
7) Observe immediately (less than 30 seconds) that the solution turns black.
8) Immediately add 0.2-5 ml of oleic acid. The solution quickly becomes clear.
9) Heat to a predetermined temperature of 285 ° C. to 360 ° C. for a maximum of 1 hour.
10) Cool to 150 ° C. and then quench with a 1: 1 mixture of ethanol and toluene added dropwise.
11) Remove the flask. Ethanol (in the case of hexadecylamine) or methanol (in the case of oleylamine) is added dropwise until aggregation is observed.
12) Centrifuge the aggregated precipitate and collect it, leaving the supernatant.
13) Further dilute the agglomerated and centrifuged precipitate. Repeat steps 9-11 until the desired purity is reached. Alternatively, steps 9-11 may be repeated on the supernatant to cause precipitation of nanoparticles of a selected size.
14) Resuspend the final precipitate in toluene, hexane or ethanol.

Example 2
In other processes, steps (2) and (3) are omitted from the process described in Example 1, and instead an oleylamine solution of sulfur and an oleylamine solution of triphenylchlorogermanium are used. These solutions are injected into a solvent heated at a temperature of 260 ° C to 360 ° C. The process continues after step (5) of the first embodiment.

Example 3
1) Put 4.5 g hexadecylamine or 7.5 ml oleylamine into a three neck round bottom flask.
2) Add 0.012 g of selenium to the flask.
3) Place the flask in a stirred heating mantle under a cold water condenser and a nitrogen purge stream.
4) Heat to 285 ° C to 300 ° C with stirring.
5) Inject a solution of 0.05 g triphenylchlorogermanium in 1.5 ml trioctylamine.
6) React for 30 minutes.
7) Cool to 150 ° C. and then quench with a 1: 1 mixture of ethanol and toluene added dropwise.
8) Remove the flask. Ethanol (in the case of hexadecylamine) or methanol (in the case of oleylamine) is added dropwise until aggregation is observed.
9) Collect the aggregated precipitate by centrifugation and leave the supernatant.
10) Further dilute the agglomerated and centrifuged precipitate. Repeat steps 9-11 until the desired purity is reached. Alternatively, steps 9-11 may be repeated on the supernatant to cause precipitation of nanoparticles of a selected size.
11) Resuspend the final precipitate in toluene, hexane or ethanol.

Example 4
1) Put 6 g hexadecylamine or 10 ml oleylamine into a three neck round bottom flask.
2) Add 0.05 g of triphenylchlorogermanium to the flask.
3) If tetraglyme is used in step 6, a predetermined amount of trioctylphosphine can be added at this stage.
4) Place the flask in a stirred heating mantle under a cold water condenser and a nitrogen purge stream.
5) Heat to 285 ° C. (boiling point of triphenylchlorogermanium) with stirring.
6) Inject 1 ml of 1M NABH ₄ soluble in either tetraglyme or trioctylphosphine. The solution quickly becomes clear.
7) Heat to a predetermined temperature of 285 ° C. to 360 ° C. for a maximum of 1 hour.
8) Cool to 150 ° C. and then quench with methanol added dropwise.
9) Remove the flask. Ethanol (in the case of hexadecylamine) or methanol (in the case of oleylamine) is added dropwise until aggregation is observed.
10) Collect the aggregated precipitate by centrifugation and leave the supernatant.
11) Further dilute the agglomerated and centrifuged precipitate. Repeat steps 9-11 until the desired purity is reached. Alternatively, steps 9-11 may be repeated on the supernatant to cause precipitation of nanoparticles of a selected size.
12) Resuspend the final precipitate in toluene, hexane or ethanol.

Example 5
In other processes, steps (2) and (3) are omitted from the process described in Example 4, and instead an oleylamine and trioctylphosphine solution of triphenylchlorogermanium is used. These solutions are poured into a solvent heated at a temperature of 260 ° C. to 360 ° C. simultaneously with step (6). The process continues after step (6) of the fourth embodiment.

  The wide variety of reducing agents can be used to promote the decomposition of aryl-containing Group IV metal precursors at temperatures above 240 ° C., even though many of the above reducing agents are Even if the temperature is unstable, it is obvious. For example, sodium naphthalide decomposes at a temperature close to the boiling point of naphthalene (˜220 ° C.), but when naphthalene is added to a mixture of triphenylchlorogermanium and sodium metal at 275 ° C., naphthalene dissolves and is in thermal equilibrium with its surroundings. The group IV metal precursor decomposes within the time it takes to reach and volatilize.

It is important that the reducing agent is homogeneously dispersed in the solution. Preferably, the reducing agent should dissolve well in useful solvent systems where crystallization occurs from a completely homogeneous dispersion of decomposed precursor molecules. However, if the distribution of the reducing agent is uniform on the length scale equivalent to the diffusion distance in the solution of the reduced group IV atom that causes crystallization, the need should be moderate. Can do. For example, the thermal decomposition of lithium aluminum hydride to LiH and AlH _{3 at} temperatures above 200 ° C. does not hinder the use of the method of the present invention. This is because the resulting highly dispersed LiH emulsion reacts completely with the precursor prior to aggregation of the insoluble hydride salt to form a homogeneous distribution of precursor degradation products in solution. Because it does. Stirring vigorously can help produce a homogeneous distribution of reduced or partially reduced precursor molecules.

  Although the invention has been described by way of example and with reference to certain embodiments, modifications and / or improvements can be made without departing from the scope of the invention as set forth in the appended claims. Should be understood.

  Further, where features or aspects of the invention are described in units of Markush groups, one skilled in the art will therefore describe the invention in units of individual members or subgroups of members of Markush groups. Recognize that.

DESCRIPTION OF SYMBOLS 1 Liquid reaction medium 2 Three-necked round bottom flask 3 Thermometer probe 4 Protective glass closed container 5 Magnetic stirrer 6 Heating 7 Gas inlet 8 Condenser 9 Water inlet and outlet 10 Exhaust outlet 70 Core 71 Surface binder

Claims (35)

Reacting a precursor of one or more Group IV metals with a decomposition accelerator in a liquid reaction medium containing a high temperature surfactant while heating at atmospheric pressure under an inert atmosphere;
Adding a surface binder;
Recovering the nanoparticles, and a method for producing nanoparticles of one or more Group IV metals or alloys thereof.   The method for producing nanoparticles according to claim 1, wherein the Group IV metal is Si, Ge, or Sn.   The method for producing nanoparticles according to claim 2, wherein the Group IV metal is Ge. The Group IV metal precursor has the general formula G (Ar) _x Y _4-x , wherein G is a Group IV metal, Ar is aryl, Y is halo, and x is at least 0 And a compound having a value of 4 or less). The method for producing nanoparticles according to claim 1, wherein The Group IV metal precursor has the general formula G (Ar) _y Y _2-y , wherein G is a Group IV metal, Ar is aryl, Y is halo, and y is at least 0 And a compound having a value of 2 or less). 2. The method for producing nanoparticles according to claim 1, wherein   The method for producing nanoparticles according to claim 4 or 5, wherein Ar is an optionally substituted phenyl.   The method for producing nanoparticles according to claim 6, wherein Ar is phenyl.   The method for producing nanoparticles according to claim 1, wherein the liquid reaction medium further contains a high-temperature solvent. The decomposition accelerator is
2. A reducing agent selected from a) a strong reducing agent, or b) S, Se, Te, P or As, or one or more of these zero-valent elements. The manufacturing method of the nanoparticle of description.   The said decomposition accelerator is selected from the compound containing 1 type, or 2 or more types of these elements of S, Se, Te, P, or As or zero valence state, The method of Claim 9 characterized by the above-mentioned. A method for producing nanoparticles.   The method for producing nanoparticles according to claim 9 or 10, wherein the decomposition accelerator is selected from compounds containing one or two of these elements in S, Se, or zero-valent state. .   The method of claim 1, further comprising adding a quenching agent before adding the surface binder.   The method for producing nanoparticles according to claim 12, wherein the step of adding a quenching agent is before adding the surface binder but after adding the decomposition accelerator.   The method for producing nanoparticles according to claim 1, wherein the surface binder is also the quenching agent.   The method for producing nanoparticles according to claim 1, wherein the reacting step includes heating to a temperature of about 100C to about 400C.   The method for producing nanoparticles according to claim 15, wherein the reacting step includes heating to a temperature of about 200C to about 400C.   The method for producing nanoparticles according to claim 16, wherein the reacting step includes heating to about 300 ° C.   The method for producing nanoparticles according to claim 1, wherein the nanoparticles have a monodispersed nanoparticle size distribution such that the standard deviation of the diameter of the nanoparticles is less than 20% of the average diameter.   The method for producing nanoparticles according to claim 18, wherein the standard deviation of the diameter of the nanoparticles is less than 5% of the average diameter.   The method for producing nanoparticles according to claim 1, wherein the nanoparticles generate luminescence in response to photoexcitation having a quantum efficiency of more than 1%.   The method for producing nanoparticles according to claim 20, wherein the quantum efficiency exceeds 20%.   The method for producing nanoparticles according to claim 1, wherein the surface binder is a carboxylic acid, an aldehyde, an amide, or an alcohol.   The method for producing nanoparticles according to claim 22, wherein the surface binder is a carboxylic acid.   The method for producing nanoparticles according to claim 1, wherein the surface binder contains an alkenyl moiety or an alkynyl moiety.   The surface binder comprises a compound of the general formula RN (wherein R is alkyl, alkenyl or aryl, and N is a functional group capable of binding to the surface of the nanoparticle). The method for producing nanoparticles according to claim 1.   24. The production of nanoparticles according to claim 22 or 23, further comprising reacting the nanoparticles with a hydride reducing agent in the absence of moisture and oxygen to obtain nanoparticles terminated with hydrogen. Method.   The hydrogen-terminated nanoparticles are represented by the general formula L—R—N (wherein R is alkyl, alkenyl, or aryl, L is a functional group having a desired function, and N is the hydrogen atom) 27. The method for producing nanoparticles according to claim 26, further comprising reacting with a compound of which is a functional group capable of binding to the surface of the nanoparticles having a terminal thereof. N is —NH ₂ , —COOH, —CONH ₂ , —CONH ₂ , —OH, —CHO, —SO ₃ H, —PO ₃ H ₂ , —PH ₂ , —SH, —CH═CH ₂ , —C 28. The method for producing nanoparticles according to claim 25 or 27, wherein the method is selected from the group consisting of ≡CH, -Cl, -F, -Br, and -I.   The method for producing nanoparticles according to claim 27, wherein L is an organic functional group.   28. The method for producing nanoparticles according to claim 27, wherein L is a functional group capable of binding to a biochemical antibody and / or a biochemically active molecule. L is —NH ₂ , —COOH, —CONH ₂ , —OH, —CHO, —SO ₃ H, —PO ₃ H ₂ , —PH ₂ , —SH, —CH═CH ₂ , —C≡CH, — 28. The method for producing nanoparticles according to claim 27, wherein the method is selected from the group consisting of Cl, -F, -Br, and -I.   A group IV or group IV metal alloy nanoparticle produced by the method for producing a nanoparticle according to any one of claims 1 to 25.   A nanoparticle having a hydrogen terminal, which is produced by the method for producing a nanoparticle according to claim 26.   32. Chemically functionalized nanoparticles produced by the method for producing nanoparticles according to any one of claims 27 to 31.   35. A device comprising the nanoparticles according to any one of claims 32 to 34.

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