KR101792315B1 - Manufacturing Method of CI(G)S Nano Particle for Preparation of Light Absorbing Layer of Solar Cell and CI(G)S Nano Particle Manufactured thereof - Google Patents

Abstract

The present invention provides a method for producing CI (G) S nanoparticles forming a light absorbing layer of a solar cell,
(i) at least one group VI source selected from the group consisting of sulfur (S), selenium (Se), or a compound comprising sulfur (S) and selenium (Se) Preparing a second solution by dispersing a copper (Cu) salt in a first solvent;
(ii) mixing and reacting the first solution and the second solution to synthesize seed particles and then separating them from the first solvent;
(iii) preparing a third solution by dispersing the separated seed particles in a second solvent together with an indium (In) salt, a Group VI source, and an additive; And
(iv) reacting a third solution to synthesize CI (G) S nanoparticles and purifying them;
(G) S nanoparticles prepared by the method and a CI (G) S nanoparticle prepared by the method.

Description

(G) S nanoparticles prepared by the method and a method of preparing the CI (G) S nanoparticles for preparing the solar cell light absorbing layer CI (G) S Nano Particle Manufactured thereof}

The present invention relates to a method for producing CI (G) S nanoparticles for manufacturing a solar cell light absorbing layer and CI (G) S nanoparticles prepared by the method.

Recently, as concerns about environmental problems and depletion of natural resources have increased, there is no problem about environmental pollution, and there is a growing interest in solar cells as energy-efficient alternative energy sources. Solar cells are classified into silicon solar cells, thin film compound solar cells, and stacked solar cells depending on their constituents, among which silicon semiconductor solar cells have been extensively studied.

However, silicon solar cells are indirect transitional semiconductor, and their optical absorption coefficient can not absorb photons more effectively than direct-type semiconductors. In addition, high purity Si is indispensably required in order to prevent recombination of electrons and holes generated in the space charge region by prolonging the life time of the carrier, and it is required to carry out a high-purity, high- Is required. Solar cells using high-purity monocrystalline Si have the disadvantage of high efficiency and high production cost, and polycrystalline Si or amorphous-Si (Si) having low efficiency is used in order to lower the production cost. However, this has a problem that the photoelectric conversion efficiency is not high and a deterioration phenomenon occurs when used for a long time.

Therefore, in recent years, a thin film type compound solar cell has been studied and developed in order to overcome the shortcomings of the silicon solar cell.

Cu (In _1-x Ga _x ) (Se _y S _1-y ) (CI (G) S) which is an I-III-VI group belonging to a ternary compound semiconductor in the thin film type compound semiconductor has a direct transitional energy band Gap, a high optical absorption coefficient, and a very electro-optically stable material, making it a very ideal material for a light absorbing layer of a solar cell.

The CI (G) S solar cell forms a photovoltaic layer with a thickness of a few microns to form a solar cell. Vacuum evaporation, which does not require a precursor, and thin film formation using a precursor, An ink coating method has been introduced in which sputtering, electrodeposition for forming a G) S thin film, and recent application of a precursor material under a non-vacuum and heat treatment thereof. Among them, the ink coating method can lower the process cost and can produce a large area uniformly, and recent studies have been actively conducted. As the precursors used in the ink coating method, metal chalcogenide compounds, bimetallic metals Various types of compounds or metals such as particles, metal salts, or metal oxides are used.

Specifically, the bimetallic metal particles are synthesized with a Cu-In alloy to solve the problem of partial unevenness, and the particle growth is fast and the reaction time is short. However, the bimetallic metal particles are partially (partially) coated with selenium (Se) There is a problem that a film lacking Se or S is formed. When a metal salt is coated, a coating film having a high film density can be obtained. However, a problem that a film is damaged or an organic residue is formed due to an anion contained in a salt have.

On the other hand, when a metal chalcogenide compound is used as a precursor, Cu-Se and In-Se compounds, and optionally, Ga-Se compounds are mixed or CuIn (Ga) Se ₂ particles are synthesized, In the case of mixed particles, a partially uneven coating film tends to be formed. In the case of CuIn (Ga) Se ₂ , since the synthesis temperature must be extremely increased by using an organic solvent having a high boiling point for controlling the uniform shape and composition, Or a long reaction time is required for grain growth.

Accordingly, there is a high need for a technique for precursor nanoparticles for the production of a solar cell light absorbing layer having uniform composition, in which all the elements necessary for thin film formation are uniformly distributed in one particle while solving the above problems, .

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art and the technical problems required from the past.

The inventors of the present application have conducted intensive research and various experiments. First, seed particles containing copper (Cu) and group VI elements are synthesized and then redispersed in another solvent to form indium (In) In the case of preparing CI (G) S nanoparticles by subsequent reaction with Group VI elements, it is possible to obtain nanoparticles having uniform distribution of copper (Cu), indium (In) and group VI elements in the particles by a simpler method As a result, it has been confirmed that a light absorption layer having a uniform composition ratio can be formed, and the present invention has been accomplished.

Accordingly, a method for producing CI (G) S nanoparticles forming a light absorbing layer of a solar cell according to the present invention,

(i) at least one group VI source selected from the group consisting of sulfur (S), selenium (Se), or a compound comprising sulfur (S) and selenium (Se) Preparing a second solution by dispersing a copper (Cu) salt in a first solvent;

(ii) mixing and reacting the first solution and the second solution to synthesize seed particles and then separating them from the first solvent;

(iii) preparing a third solution by dispersing the separated seed particles in a second solvent together with an indium (In) salt, a Group VI source, and an additive; And

(iv) reacting a third solution to synthesize CI (G) S nanoparticles and purifying them;

And a control unit.

The seed particles may be copper chalcogenide nanoparticles represented by the following formula (1).

Cu _2-x S _1-y Se _y (1)

In this formula,

0? X? 0.25, 0? Y?

In general, when a precursor for preparing a thin film of CI (G) S prepared by a solution process is prepared, a thin film having a uniform composition ratio can be easily obtained when various elements are contained in one element. Therefore, the inventors of the present application have conducted intensive research and have found that when the CI (G) S nanoparticles are prepared according to the present invention, the copper chalcogenide seed particles serve as a guide (G) S nanoparticles with uniform distribution of all the elements in the final particle are formed by reacting the indium (In) and the group VI elements under the subsequent reaction conditions to form the final particles uniformly. .

In one specific example, the third solution of step (iii) may further comprise a gallium (Ga) salt. Specifically, when the gallium (Ga) salt is not included, the resulting CIS nanoparticles are formed. When the gallium (Ga) salt is further included, the resultant CIGS Thereby forming nanoparticles.

Meanwhile, the first solution and / or the second solution of the step (i) may further include a capping agent.

The capping agent not only controls the size and particle size of the CI (G) S nanoparticles synthesized by being included in the solution process, but also contains atoms such as N, O, S and the like, so that the lone pair electron (G) S nanoparticles by binding easily to the surface of the CI (G) S nanoparticles by the action of the CI (G) S nanoparticles.

Examples of such a capping agent include, but are not limited to, polyvinylpyrrolidone (PVP), sodium dodecyl sulphate (SDS), polyvinyl alcohol, ethyl cellulose, Sodium laurate, sodium L-tartrate dibasic dehydrate, potassium sodium tartrate, sodium acrylate, poly (acrylic acid sodium salt), sodium citrate citrate, citric acid, trisodium citrate, disodium citrate, sodium gluconate, sodium ascorbate, sorbitol, triethyl phosphate, ethylene But are not limited to, ethylene diamine, propylene diamine, 1,2-ethanedithiol, ethanethiol, ascorbic acid, citric acid, Acid (tartaric acid), one is selected from captopril Murray ethanol (2-mercaptoethanol), and the group consisting of amino ethanethiol (2-aminoethanethiol) may be equal to or greater than.

At this time, the content of the capping agent may be less than 20 mol based on 1 mol of the copper (Cu) salt when the first solution and the second solution are mixed.

When the content of the capping agent is more than 20 times the mole of the copper (Cu) salt, the purification process of the CI (G) S nanoparticles is difficult and the purity of the particles may be lowered.

In one specific example, the first solvent may be an aqueous solvent and the second solvent may be an alcohol-based solvent. At this time, the alcohol-based solvent may be at least one selected from the group consisting of substituted or unsubstituted methanol, substituted or unsubstituted ethanol, substituted or unsubstituted propanol, and substituted or unsubstituted butanol.

In general, in order to use nanoparticles as precursors for preparing thin films, it is necessary to use easily removable additives and solvents. In the past, as a condition for forming a thin film having excellent performance, uniform shape and composition control of precursor nanoparticles An organic solvent having a high boiling point was used, and therefore, there was a problem that the synthesis was required to raise the synthesis temperature by more than 200 deg.

On the other hand, in the method for producing CI (G) S nanoparticles according to the present invention, when an aqueous solvent and an alcohol-based solvent are used as the solvent, the final particles can be synthesized at a lower temperature, It is effective.

This is because, in order to synthesize seed particles or CI (G) S nanoparticles, it is necessary to raise the reaction temperature to near the boiling point of the solvent, and the reaction temperature depends on the kind of the first solvent and the second solvent.

Thus, in one specific example, the reaction temperature in step (ii) may be from 70 degrees Celsius to 100 degrees Celsius, and the reaction temperature in step (iv) may be from 50 degrees Celsius to below the boiling point of the second solvent.

Outside of the above range, synthesis at a too low temperature does not work well, and conversely, a temperature higher than necessary beyond the boiling point is not preferable since the ease of production is inferior in terms of economy and efficiency.

In one specific example, the additive of the above process (iii) may be an amine compound or a reducing agent, which is included in order to increase the yield and control particle formation during the subsequent reaction of the indium (In) salt with the Group VI source .

The amine compound may be at least one member selected from the group consisting of ammonia (NH ₃ ), alkylamines, dialkylamines, aromatic amines, and more specifically, an aromatic amine. The aromatic amine may be any one selected from the group consisting of aniline, pyridine, and pyrrole, and more specifically, pyridine.

Such an amine compound may be added in an amount of 10 to 30% by weight, particularly 10 to 20% by weight based on the total weight of the third solution.

If it is contained in an amount of less than 10% by weight, it is not easy to control the shape of the synthesized nanoparticles. If it exceeds 30% by weight, residues or impurities of the added amine are produced Can be, is not desirable.

The reducing agent may be hydrazine, LiBH₄, NaBH₄, KBH₄, Ca (BH₄)₂, Mg (BH₄)₂, LiB (Et)₃H₂, NaBH₃(CN), NaBH (OAc)_3,Ascorbic acid and triethanolamine, and may be at least one selected from the group consisting of hydrazine.

The reducing agent may be added in an amount of 0.5 to 3% by weight, particularly 0.5 to 2% by weight based on the total weight of the third solution.

If the content of the seed particles is less than 0.5% by weight, the reaction time must be prolonged to increase the yield of the reaction. If the content of the seed particles exceeds 3% by weight, the seed particles of the step (ii) This is undesirable.

Specifically, the additive such as the amine compound or the reducing agent may be determined according to the kind of the second solvent which is the alcoholic solvent. In one specific example, when the second solvent is the unsubstituted ethanol, For example, pyridine, and the second solvent may be a substituted ethanol, for example, ethanol substituted with an alkoxy group of C1-C5, specifically, 2-methoxyethanol, 2-ethoxyethanol, 2- Propoxyethanol, and 2-butoxyethanol, the additive may be a reducing agent

This is because the reactivity and reaction path of the indium (In) salt and the group VI source are different depending on whether the second solvent is substituted ethanol or unsubstituted ethanol.

In one specific example, in step (iii), the indium (In) salt may include 1 mole to 2 moles of indium (In) relative to 1 mole of copper (Cu) of the seed particles.

If indium (In) is contained in an amount of less than 1 mole based on 1 mole of copper (Cu), there is a problem that Cu impurities may be formed. When the amount of indium (In) exceeds 2 moles, , It is difficult to form a p-type CIGS light absorption layer thin film, which is not preferable because of poor performance.

The metal salts and the Group VI sources which are specific materials used in the production method of the present invention are not limited as long as they include these elements. For example, copper (Cu), indium (In) The salt which is the source of the salt may be selected from the group consisting of chloride, bromide, iodide, nitrate, nitrite, sulfate, acetate, sulphite, acetylacetonate salt may be one or more types selected from the group consisting of (acetylacetoante) and hydroxide (hydroxide), the group VI sources _{Se, Na 2 Se, K 2} Se, CaSe, (CH 3) 2 Se, SeO ₂ , SeCl ₄ , H ₂ SeO ₃ , H ₂ SeO ₄ , Na ₂ S, K ₂ S, CaS, (CH ₃ ) ₂ S, H ₂ SO ₄ , S, Na ₂ S ₂ O ₃ , NH ₂ SO ₃ H and their hydrates, and thiourea, thioacetamide, and selenourea. In the present invention,

The CI (G) S nanoparticles synthesized as described above may have an average particle diameter of 30 nm to 100 nm, and more specifically, an average particle diameter of 50 nm to 100 nm.

If the particle size of the nanoparticles exceeds 100 nm, it is difficult to form a light absorbing layer having increased film density due to a large porosity in the thin film. When the particle diameter is less than 30 nm, And it is difficult to produce a crack due to increase of the surface energy of the nanoparticles, which makes the coating process difficult.

The present invention also provides CI (G) S nanoparticles prepared by the above-mentioned production method, provides an ink composition for producing a light absorbing layer containing the CI (S) S nanoparticles, and provides a thin film produced using the ink composition.

The light-absorbing layer thin film is prepared by dispersing CI (G) S nanoparticles according to the present invention in a solvent to prepare an ink composition, coating it on a substrate on which electrodes are formed, and drying and heat-treating the same.

At this time, the coating layer forming the light absorbing layer may have a thickness of 0.5 micrometers to 3 micrometers, and more specifically, may have a thickness of 2 micrometers to 3 micrometers.

If the thickness of the thin film is less than 0.5 microns, the density and quantity of the light absorbing layer are not sufficient and the desired photoelectric efficiency can not be obtained. When the thin film is more than 3 microns, the distance through which the charge carrier moves increases The probability of recombination is increased, resulting in a reduction in efficiency.

The solvent for the preparation of the ink composition is not particularly limited as long as it is a general organic solvent and can be used in the form of alkanes, alkenes, alkynes, aromatics, ketons ), Nitriles, ethers, esters, organic halides, alcohols, amines, thiols, carboxylic acids (such as, for example, organic solvents selected from organic acids selected from organic acids, carboxylic acids, phosphines, phosphites, phosphates, sulfoxides and amides are used alone or in combination with one or more Organic solvents may be mixed.

Specifically, the alcohol-based solvent is selected from the group consisting of ethanol, 1-propanol, 2-propanol, 1-pentanol, 2- Hexanol, 2-hexanol, 3-hexanol, heptanol, octanol, EG (ethylene glycol), DEGMEE (diethylene glycol) monoethyl ether (EGMME), ethylene glycol monoethyl ether (EGMEE), ethylene glycol dimethyl ether (EGDEE), ethylene glycol monopropyl ether (EGMPE), ethylene glycol monobutyl ether 2-methyl-1-propanol, cyclopentanol, cyclohexanol, propylene glycol propyl ether (PGPE), DEGDME (diethylene glycol dimethyl ether), 1 (1,3-propanediol), 1,4-BD (1,4-butanediol), 1,3-BD (1,3-butanediol) Alpha-terpineol, DEG (diethylene glycol), glycerol, 2-ethylamino ethanol, (2-amino-2-methyl-1-propanol), 2- (methylamino) ethanol, 2- It can be used every day.

The amine-based solvent is selected from the group consisting of triethylamine, dibutylamine, dipropylamine, butylamine, ethanolamine, DETA (diethylenetriamine), TETA (triethylenetetraine) Triethanolamine, 2-aminoethyl piperazine, 2-hydroxyethyl piperazine, dibutylamine, and tris (2-aminoethyl) amine (tris (2-aminoethyl) amine).

The thiol-based solvent may be one or more kinds of mixed solvents selected from among 1,2-ethanedithiol, pentanethiol, hexanethiol, and mercaptoethanol.

The alkane solvent may be one or more kinds of mixed solvents selected from the group consisting of hexane, heptane and octane.

The aromatic solvent may be one or more kinds of mixed solvents selected from the group consisting of toluene, xylene, nitrobenzene, and pyridine.

The organic halide solvent may be at least one compound selected from the group consisting of chloroform, methylene chloride, tetrachloromethane, dichloroethane, and chlorobenzene. have.

The nitrile solvent may be acetonitrile.

The ketone solvent may be one or more kinds of mixed solvents selected from the group consisting of acetone, cyclohexanone, cyclopentanone, and acetyl acetone.

The ethers solvent may be one or more daily for mixing selected from ethyl ether, tetrahydrofurane, and 1,4-dioxane.

The sulfoxides solvent may be one or more daily for mixing selected from dimethyl sulfoxide (DMSO) and sulfolane.

The amide solvent may be one or more kinds of mixed solvents selected from DMF (dimethyl formamide), and NMP (n-methyl-2-pyrrolidone).

The ester solvent may be one or more daily for mixing selected from ethyl lactate, r-butyrolactone, and ethyl acetoacetate.

The carboxylic acid solvent may be selected from the group consisting of propionic acid, hexanoic acid, meso-2,3-dimercaptosuccinic acid, thiolactic acid ), And thioglycolic acid.

However, the solvents may be but one example.

In some cases, it may be prepared by further adding an additive to the ink.

The additive may, for example, comprise a dispersant, a surfactant, a polymer, a binder, a crosslinking agent, an emulsifier, a defoamer, a desiccant, a filler, an extender, a thickener, a film conditioning agent, an antioxidant, a flow agent, Polyvinylpyrrolidone (PVP), polyvinyl alcohol, Anti-terra 204, Anti-terra 205, and the like can be used. Ethyl cellulose, and DISPERS BYK 110 (DispersBYK 110).

The coating may be applied, for example, by a wet coating, a spray coating, a spin coating, a doctor blade coating, a contact printing, an upper feed reverse printing, a lower feed reverse printing, nozzle feed reverse printing, gravure printing, micro gravure printing, reverse micro gravure printing, roller coating, slot die coating, capillary coating, inkjet printing, jet printing, ) Deposition, and spray deposition.

The heat treatment may be performed at a temperature in the range of 400 to 900 degrees Celsius.

On the other hand, in order to produce a light absorbing layer thin film having a higher density, a selenizing process may be selectively included, and the selenifying process may be performed by various methods.

In the first example, it can be achieved by dispersing S and / or Se together with the CI (G) S nanoparticles in a solvent in the form of particles to prepare an ink composition and coating it on a substrate on which electrodes are formed, have.

In the second example, this heat treatment can be accomplished by carrying out the conditions under which S or Se is present.

Specifically, the condition in which the S or Se element is present may be supplied in the form of a gas of H ₂ S or H ₂ Se, or by heating Se or S to supply the gas.

In the third example, it can be achieved by laminating S or Se after the coating of the ink composition and then heat-treating. Specifically, the lamination may be performed by a solution process or may be performed by a deposition method.

Furthermore, the present invention provides a thin film solar cell manufactured using the thin film.

A method of manufacturing a thin film solar cell is already known in the art and a description thereof will be omitted herein.

As described above, the CI (G) S nanoparticles according to the present invention are synthesized by first synthesizing seed particles containing copper (Cu) and group VI elements and then redispersing them in another solvent to form indium (In ) Salt and a VI group element, it is possible to obtain nanoparticles in which copper (Cu), indium (In) and group VI elements are evenly distributed in the final particles even in a more easy manufacturing process As a result, there is an effect that a light absorbing layer having a uniform composition ratio as a whole can be formed.

1 is a transmission electron microscope (TEM) photograph of Cu ₂ Se seed particles formed in Production Example 1;
2 is an electron microscope (SEM) photograph of the CISSe nanoparticles prepared in Example 1;
3 is a transmission electron microscope (TEM) photograph of the CISSe nanoparticles prepared in Example 1;
Figure 4 is an EDS mapping result showing the compositional uniformity of the CISSe nanoparticles prepared in Example 1;
5 is an electron microscope (SEM) photograph of the CISSe nanoparticles prepared in Example 2;
6 is an electron micrograph (SEM) photograph of the CISSe nanoparticles prepared in Example 3;
7 is SEM photographs of the thin films prepared in Example 4. Fig.

Hereinafter, the present invention will be described with reference to Examples. However, the following Examples are intended to illustrate the present invention, and the scope of the present invention is not limited thereto.

≪ Preparation Example 1 &

Synthesis of Cu ₂ Se particles

100 mL of an aqueous solution containing 10 mmol of CuSO ₄ was added dropwise to 150 mL of an aqueous solution containing 5 mmol of H ₂ SeO ₃ and 1 mmol of SDS, followed by stirring for 2 hours to effect reaction, and the formed particles were purified by centrifugation Cu ₂ Se nanoparticles were prepared. A transmission electron microscope (SEM) photograph of the formed particles was shown in Fig.

≪ Example 1 >

5 mmol of Cu ₂ Se synthesized in Preparation Example 1, 100 g of pyridine, 15 mmol of thioacetamide and 10 mmol of InCl ₃ were placed in 200 mL of an ethanol solvent and heated to 78 ° C., After stirring for 3 hours, it was purified by centrifugation to obtain Cu _0.98 In _1.00 Se _0.42 S _2.05 nanoparticles. An electron micrograph (SEM, TEM) of the formed particles is shown in Figs. 2 and 3, and an EDS-mapping photograph is shown in Fig.

2 to 4, it can be confirmed that CISSe nanoparticles having Cu, In, S, and Se uniformly distributed in one particle are synthesized even at a relatively low temperature by the above manufacturing method.

≪ Example 2 >

Preparation Example 1 The synthesis Cu ₂ Se 5 mmol from and put into the pyridine 100g, thioacetamide (thioacetamide) of 15 mmol, InCl ₃ 5 mmol, and GaI ₃ 5 mmol in ethanol solvent of 200 mL, heated to 78 degrees The mixture was stirred at the same temperature for 3 hours and purified by centrifugation to obtain Cu _1.31 In _0.49 Se _0.88 S _1.50 nanoparticles. An electron micrograph (SEM) obtained by analyzing the formed particles is shown in Fig.

≪ Example 3 >

A solution of 5 mmol of Cu ₂ Se synthesized in Preparation Example 1 in 2-isopropoxy ethanol was added to 10 mmol of thioacetamide, 2.5 mmol of sodium dodecyl sulfate (SDS) and 3 g of hydrazine Was added to 250 mL of the same solvent. Thereafter, a solution prepared by dissolving 5 mmol of InCl _{3 in} 50 mL of 2-isopropoxyethanol was added dropwise to the above solution, heated to 80 ° C, stirred for 3 hours while maintaining the temperature, and then purified by centrifugation to obtain Cu _1.01 In _1.00 Se _0.70 S _1.35 nanoparticles were obtained. An electron micrograph (SEM) obtained by analyzing the formed particles is shown in Fig.

<Example 4>

The CISSe nanoparticles formed in Example 1 were dispersed in a solvent composed of an alcohol-based mixed solvent at a concentration of 20% and mixed with beads for 3 days to prepare an ink composition. The ink composition was coated on a substrate obtained by vapor-depositing Mo on a glass substrate to prepare a coating film for CISSe thin film production. After drying to 200 ° C, CISSe thin film was obtained by heat treatment at 600 ° C for 5 minutes under Se atmosphere. The planar shape and the cross-sectional shape of the obtained thin film are shown in Fig.

Referring to FIG. 7, it can be confirmed that the film density is excellent.

<Experimental Example 1>

A CdS layer was formed on the CISSe thin film prepared in Example 2 by using a chemical bath deposition (CBD) method, and then a ZnO layer and an ITO layer were sequentially stacked by sputtering to form a thin film, To prepare a thin film solar cell. The photoelectric efficiency of the thin film solar cell was measured and the results are shown in Table 1 below.

J _sc (mA / cm ² ) V _oc (V) FF Photoelectric efficiency (%) Example 2 16.23 0.33 33.42 1.8

J _sc , a variable for determining the efficiency of the solar cell shown in Table 1, means the current density, V _oc means the open circuit voltage measured at the zero output current, and the photoelectric efficiency is the energy of the light incident on the solar panel (Fill factor) means a value obtained by dividing the product of the current density at the maximum power point and the voltage value by the product of Voc and J _sc .

As can be seen from Table 1, when the CISSe nanoparticles prepared according to the present invention are used for forming a light absorbing layer, excellent photoelectric efficiency is exhibited.

Those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims (26)

A method for producing CI (G) S nanoparticles forming a light absorbing layer of a solar cell,
(i) at least one group VI source selected from the group consisting of sulfur (S), selenium (Se), or a compound comprising sulfur (S) and selenium (Se) Preparing a second solution by dispersing a copper (Cu) salt in a first solvent;
(ii) mixing and reacting the first solution and the second solution to synthesize seed particles and then separating them from the first solvent;
(iii) preparing a third solution by dispersing the separated seed particles in a second solvent together with an indium (In) salt, a Group VI source, and an additive; And
(iv) reacting a third solution to synthesize CI (G) S nanoparticles and purifying them;
(G) &lt; / RTI &gt; S nanoparticles. The method of claim 1, wherein the third solution of step (iii) further comprises a gallium (Ga) salt. The method of claim 1, wherein the first solution and / or the second solution of step (i) further comprises a capping agent. 4. The method of claim 3, wherein the capping agent is selected from the group consisting of polyvinylpyrrolidone (PVP), sodium dodecyl sulphate (SDS), polyvinyl alcohol, ethyl cellulose, Sodium citrate, sodium citrate dibasic dehydrate, potassium sodium tartrate, sodium acrylate, poly (acrylic acid sodium salt), sodium citrate, citric acid, But are not limited to, trisodium citrate, disodium citrate, sodium gluconate, sodium ascorbate, sorbitol, triethyl phosphate, ethylene diamine Propylene diamine, 1,2-ethanedithiol, ethanethiol, ascorbic acid, citric acid, tartaric acid, mercaptosilicate, 2-mercaptoethanol, and 2-aminoethanethiol. 2. The method according to claim 1, wherein the CI (G) S nanoparticles are at least one selected from the group consisting of 2-mercaptoethanol and 2-aminoethanethiol. 4. The method of claim 3, wherein the content of the capping agent is 20 mol or less based on 1 mol of the copper (Cu) salt when the first solution and the second solution are mixed. Gt; The method according to claim 1, wherein the first solvent is an aqueous solvent and the second solvent is an alcohol-based solvent. 7. The process according to claim 6, wherein the alcoholic solvent is at least one selected from the group consisting of substituted or unsubstituted methanol, substituted or unsubstituted ethanol, substituted or unsubstituted propanol, and substituted or unsubstituted butanol. Method for manufacturing S nanoparticles. The method according to claim 1, wherein the additive is an amine compound or a reducing agent. 9. The method of claim 8, wherein the amine compound is one or more selected from the group consisting of ammonia (NH ₃ ), alkylamine, dialkylamine, and aromatic amine. A method for producing nanoparticles. The method according to claim 8, wherein the amine compound is an aromatic amine, and the aromatic amine is at least one selected from the group consisting of aniline, pyridine, and pyrrole. Method for manufacturing S nanoparticles. 9. The method of claim 8, wherein the reducing agent is hydrazine, LiBH₄, NaBH₄, KBH₄, Ca (BH₄)₂, Mg (BH₄)₂, LiB (Et)₃H₂, NaBH₃(CN), NaBH (OAc)_3,(G) S nanoparticles according to claim 1, wherein the at least one selected from the group consisting of ascorbic acid and triethanolamine is at least one selected from the group consisting of ascorbic acid and triethanolamine. 9. The method according to claim 8, wherein the amine compound is added in an amount of 10 to 30 wt% based on the total weight of the third solution. 9. The method of claim 8, wherein the reducing agent is added in an amount of 0.5 to 3% by weight based on the total weight of the third solution. The method according to claim 1, wherein the reaction temperature of step (iv) is in the range of 50 ° C to below the boiling point of the second solvent. The method for producing CI (G) S nanoparticles according to claim 1, wherein the second solvent is an unsubstituted ethanol and the additive is an amine compound. The method of claim 1, wherein the second solvent is ethanol substituted with a C1-C5 alkoxy group, and the additive is a reducing agent. The method according to claim 1, wherein the seed particles are copper chalcogenide nanoparticles represented by the following formula (1): &lt; EMI ID =
Cu _2-x S _1-y Se _y (1)
In this formula,
0? X? 0.25, 0? Y? The method of claim 1 or 2, wherein the salt is selected from the group consisting of chloride, bromide, iodide, nitrate, nitrite, sulfate, acetate, (G) S nanoparticles characterized in that they are at least one form selected from the group consisting of sulfite, acetylacetoate and hydroxide. The method of claim 1, wherein the Group VI sources _{Se, Na 2 Se, K 2} Se, CaSe, (CH 3) 2 Se, SeO 2, SeCl 4, H 2 SeO 3, H 2 SeO 4, Na 2 S, K ₂ S, CaS, (CH ₃ ) ₂ S, H ₂ SO ₄ , S, Na ₂ S ₂ O ₃ , NH ₂ SO ₃ H and their hydrates, thiourea, thioacetamide, , And selenourea. 2. The method according to claim 1, wherein the CI (G) S nanoparticle is at least one selected from the group consisting of selenourea, and selenourea. The method according to claim 1, wherein in step (iii), the indium (In) salt is added so that 1 mole to 2 moles of indium (In) is added to 1 mole of copper (Cu) Method for manufacturing S nanoparticles. The method according to claim 1, wherein the synthesized CI (G) S nanoparticles have an average particle diameter of 30 nm to 100 nm. The method according to claim 21, wherein the CI (G) S nanoparticles have an average particle diameter of 50 nm to 100 nm. delete delete delete delete

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