KR20150066762A - apparatus for manufacturing nanocrystals having Hybrid Flow Reactor and manufacturing method of CuInS2/ZnS nanocrystals - Google Patents

Abstract

The present invention relates to an apparatus for manufacturing nanocrystals having a hybrid flow reactor and a manufacturing method of CuInS2/ZnS nanocrystals using the same, and, more specifically, relates to an apparatus for manufacturing nanocrystals having a hybrid flow reactor and a manufacturing method of CuInS2/ZnS nanocrystals having excellent light stability using the same so that the nanocrystals can be synthesized in volume. To the end, in the present invention, the apparatus for manufacturing the nanocrystals is capable of producing uniform nanocrystals in a rapid time in volume to generate a continuous reaction, by connecting a mixer in a row. In addition, eco-friendly CuInS2 nanocrystals of which light stability and chemical stability are excellent are manufactured using the manufacturing apparatus, and, accordingly, the nanocrystals can be easily manufactured in volume with a high yield while the sizes of the nanocrystals are uniformly maintained.

Description

[0001] The present invention relates to an apparatus for manufacturing nanocrystals including a continuous flow reactor and a method for manufacturing CuInS2 / ZnS nanocrystals using the same,

The present invention relates to an apparatus for producing nanocrystals including a continuous flow reactor and a method for producing CuInS ₂ / ZnS nanocrystals using the same, and more particularly, to a nanocrystal- And a method for producing CuInS ₂ / ZnS nanocrystals having excellent optical stability using the same.

Nanocrystals with specific optical / electrical properties that are not possessed by semiconducting materials in the bulk state are attracting attention as nano-materials such as next-generation high-brightness LEDs, biosensors, lasers and solar cells.

Of the nanocrystals developed so far, colloidal II-VI compound nanocrystals have attracted much attention due to their high quantum efficiency and optical and chemical stability of over 60%. Representative II-VI compound nanocrystals include CdSe, have. Such a quantum dot has a problem that it contains a heavy metal having high toxicity such as Cd ^{2 +} and Se ^{2 -} .

In order to solve this problem, nanocrystals such as InP including Group III-V compounds have been studied as substitutes for Group II-VI compounds. These III-V compounds have the advantage of less toxic damage by heavy metals. However, it has a problem that it is not suitable for commercialization because it requires toxic expensive compounds having spontaneous ignitability in the synthesis process (Non-Patent Document 1)

A semiconductor nanocrystal capable of overcoming these problems Ⅰ-Ⅲ Ⅵ nano-crystal and the spotlight _second series compound, a representative Ⅰ-Ⅲ _Ⅵ-2 family compound nanocrystals may include CuInS _2.

On the other hand, as a method of producing the nanocrystals, a dry chemical method of forming quantum dots by lattice mismatching with a substrate prepared in vacuum using an MOCVD method has been used. In this method, And it is possible to arrange and observe them at the same time, but there is a disadvantage that expensive synthesis equipment is required and it is difficult to mass-synthesize quantum dots of uniform size.

In order to solve the above disadvantages, a wet chemical method for synthesizing nanocrystals using a surfactant has been developed. However, since a manufacturing process is complicated and only a very small amount can be produced due to loss of a post- The problem still exists.

In order to solve this problem, the use of a large-capacity reactor causes another problem that the uniformity and the quality are deteriorated as a whole, which directly affects the optical / electrical characteristics of the particle size of the produced nanocrystals, .

To this end, a continuous process using microchannels has been developed. Since the microchannel can be heated to the reaction temperature instantaneously by using a continuous fluid flowing in the micro space and the microchannel can maintain the reaction conditions uniformly, the diameter of the microchannel is as small as 1 to 1 mm, There is a problem that the flow path is clogged due to deposition of nanoparticles, so that there is a problem in mass production despite the continuous process (Patent Document 1)

Patent Document 1: JP-A-2003-225900

Non-Patent Document 1. J. Phys. Chem. B., 1997,101, 2904.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art, and it is an object of the present invention to provide a nanocrystal manufacturing apparatus capable of continuously manufacturing high-efficiency nanocrystals.

Another object of the present invention is to provide a method for mass-producing CuInS ₂ / ZnS nanocrystals having uniform and high efficiency of light emission using the above apparatus.

In order to achieve the above-mentioned object, the present invention provides a microwave oven comprising a first mixer, a second mixer connected in series with the first mixer, a baking furnace connected to the second mixer, The present invention provides an apparatus for producing nanocrystals including a regulating pump.

The first mixer and the second mixer may be connected to the first flow channel, and the second mixer, the baking furnace, and the flow rate adjusting pump may be connected to the second flow channel.

The first mixer and the second mixer may further include a mixer heating unit for adjusting the temperature of each mixer.

The first mixer may include a first inlet through which the core precursor solution is supplied, a second inlet through which a vacuum state or nitrogen gas is supplied, And a first outlet communicating with the second mixer through the first flow channel.

The second mixer includes a third inlet through which the core solution is supplied through the first flow channel connected to the first mixer, and a fourth inlet through which the shell precursor solution is supplied; And a second outlet connected to the baking furnace and the second flow channel.

The diameter of the first flow channel and the second flow channel may be 2.5 to 3.5 mm and the length of the first flow channel may be 1 to 10 m and the length of the second flow channel may be 2 to 20 m have.

The present invention also provides a process for the preparation of CuInS ₂ / ZnS nanocrystal comprising the, following steps as a method of manufacturing a CuInS ₂ / ZnS nanocrystals using the nano-crystal manufacturing apparatus.

(I) mixing and heating the core precursor solution supplied to the first mixer to form a core,

II) mixing and heating the shell precursor solution supplied to the second mixer,

III) feeding the core solution formed in step I) to a second mixer heated in step II) and mixing with the shell precursor solution, and

IV) The mixed solution is supplied to the calcining furnace at a constant rate through a flow rate control pump to obtain nanocrystals.

And then purifying the obtained nanocrystals.

The core precursor solution may include a copper precursor, an indium precursor, and a sulfur precursor, and the shell precursor solution may include a zinc precursor and a sulfur precursor.

The copper precursor may be copper iodide (CuI), the indium precursor may be indium acetate (In (OAc) ₃ ), and the sulfur precursor may be dodecanethiol (DDT).

The zinc precursor may be zinc stearate or zinc acetate and the sulfur precursor may be dodecanethiol.

Wherein the step (I) comprises the steps of: (i) heating the first mixer at 120 to 170 DEG C for 10 to 60 minutes; (I-ii) heating the heated first mixer at 190 to 230 DEG C for 1 to 60 minutes; And (I-iii) cooling the heated first mixer to 60 to 100 ° C.

The step II) comprises the steps of: II-i) heating the second mixer at 100 to 150 DEG C for 1 to 60 minutes; And II-ii) cooling the heated second mixer to 60 to 100 占 폚.

The flow rate controlled by the flow rate adjusting pump may be 1 to 3 mL / min.

And the baking furnace is maintained at 300 to 350 ° C.

The features and advantages of the present invention will become more apparent from the following detailed description based on the accompanying drawings.

Prior to this, terms and words used in the present specification and claims should not be construed in a conventional, dictionary sense, and should not be construed as defining the concept of a term appropriately in order to describe the inventor in his or her best way. It should be construed in accordance with the meaning and concept consistent with the technical idea of the present invention.

According to the present invention, the apparatus for producing nanocrystals according to the present invention can produce a uniform mass of nanocrystals in a short time by continuously reacting by connecting a mixer in a row.

In addition, it has excellent light stability and chemical stability, and is environmentally friendly CuInS ₂ By manufacturing the nanocrystals using the manufacturing apparatus, it is possible to mass-produce the nanocrystals easily at a high yield while maintaining the size of the nanocrystals uniformly.

1 is a schematic view showing the structure of an apparatus for producing nanocrystals according to the present invention.
FIG. 2A is a photograph showing the measurement of the weight of the CuInS ₂ / ZnS nanocrystal prepared in accordance with the preparation example of the present invention, 1.58 g of the CuInS ₂ / ZnS nanocrystal after drying, and the photograph taken under a 365 nm ultraviolet lamp.
FIG. 2B shows absorption and emission spectra of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention.
3 is a graph showing XRD (X-ray diffraction) measurement of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention.
Figures 4a and 4b are transmission electron microscope (TEM) image of the CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the present invention, Figure 4c of the CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the invention It is a graph obtained using a scanning electron microscope as a result of EDX.
5A is an XPS analysis graph of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention, wherein FIG. 5A is an overview spectrum showing Cu, In, Zn and S elements, and FIGS. 5B to 5E are Cu 2P , In 3d, Zn 2p, and S 2p peak portions are scanned at high resolution.
6 is placed the ultraviolet lamp and the distance of 10 cm in a dark environment, prepared according to Preparation measurement CuInS ₂ / ZnS nm to determine the light stability of the CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the invention And the emission spectrum of the crystal.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, particular advantages and novel features of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, and from the preferred manufacture examples. It should be noted that, in the present specification, the reference numerals are added to the constituent elements of the drawings, and the same constituent elements are assigned the same number as much as possible even if they are displayed on different drawings. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail.

Hereinafter, a nanocrystal production apparatus and a CuInS ₂ / ZnS nanocrystal mass synthesis method will be described in detail with reference to the accompanying drawings.

1 is a schematic view showing the structure of a nanocrystal manufacturing apparatus according to the present invention.

The apparatus for producing nanocrystals according to the present invention comprises a first mixer 100 and a second mixer 200 connected in series with the first mixer 100, A furnace 400 connected to the mixer 200 and a flow control pump 300 provided between the firing furnace 400 and the second mixer 200.

The first mixer 100 and the second mixer 200 may be connected by a first flow channel 500 and the second mixer 200 and the firing furnace 400 may be connected by a second flow channel 600 ).

The first flow channel 500 and the second flow channel 600 may be any one selected from the group consisting of glass, plastic, and steel, and each flow channel 500, 600 may have a diameter of 2.5 to 3.5 mm Lt; / RTI >

If the diameters of the flow channels 500 and 600 are less than 2.5 mm, clogging of the flow channels occurs due to deposition of the generated nanoparticles. When the diameters of the flow channels 500 and 600 are more than 3.5 mm, It is preferable to maintain the above range.

The length of the first flow channel 500 provided in the apparatus for manufacturing nanocrystals of the present invention may be controlled within a range of 1 to 10 m and the length of the second flow channel 600 may be controlled within a range of 2 to 20 m , Which may affect the reaction time of the liquid flowing in the first and second flow channels 500 and 600, it is preferable to adjust the length of the flow channels 500 and 600 within the range, When the lengths of the channels 500 and 600 are shorter than the minimum length, the reaction time is shortened and the reaction can not be performed uniformly and unreacted materials are generated. Therefore, a large number of reactors are required and are inefficient. The configuration is inefficient, and the reaction time becomes long. Therefore, the manufacturing cost is increased without any further effect, which is not economical.

The flow control pump 300 may be included at any one position of the second flow channel 600 connecting the second mixer 200 and the calcining furnace 400 to pass through the second flow channel The flow rate and speed can be adjusted constantly.

Although the second flow channel 600 is shown as a straight line in the drawing, the firing furnace 400 may be spirally wound or have another curved shape to enhance the heating or cooling effect. More preferably, the second flow channel 600 is spirally wound on the firing furnace 400, so that the liquid flowing through the second flow channel 600 can be heated more efficiently through the second flow channel 600.

In addition, the temperature of the liquid flowing in the second flow channel 600 can be controlled by controlling the temperature of the firing furnace 400.

The first mixer 100 and the second mixer 200 may further include mixer heating units 104 and 204 to inject the first mixer 100 or the second mixer 200 Respectively, depending on the solution.

The first mixer 100 includes a first input port 101 and a second input port 102; And a first outlet 103. The first mixer 100 may supply the core precursor solution into the first mixer 100 through the first inlet 101 and the second inlet 102 through the first inlet 101, May be connected to a device (not shown) for filling the first mixer 100 with nitrogen gas or for maintaining the interior of the first mixer 100 in a vacuum state, 1 mixer 100 can be supplied to the second mixer 200.

The second mixer 200 includes a third input port 201 and a fourth input port 202; And the second mixer 200 may supply the core solution generated in the first mixer 100 into the second mixer 200 through the third inlet 201 And a shell precursor solution can be supplied into the second mixer 200 through the fourth inlet 202. The mixed solution in the second mixer 200 can be supplied through the second outlet 203 to the sintering furnace 2 flow channel (600).

The first mixer 100 and the second mixer 200 are connected to the first, second, third and fourth inlet ports 101, 102, 201 and 202 and the first and second outlet ports 103 and 203 The inlet may further include an opening / closing device (not shown in the figure) that can be easily separated and installed.

According to another aspect of the present invention, there is provided a method for fabricating CuInS ₂ / ZnS nanocrystals using the nanocrystal fabrication apparatus, comprising the following steps.

I) mixing and heating the core precursor solution supplied to the first mixer to form a core.

II) mixing and heating the shell precursor solution supplied to the second mixer.

III) feeding the core solution formed in the step I) to a second mixer heated in step II) and mixing with the shell precursor solution. And

IV) The mixed solution is supplied to the calcining furnace at a constant rate through a flow rate control pump to obtain nanocrystals.

The above manufacturing method will be described in more detail.

First, the core precursor solution is supplied into the first mixer 100 through the first inlet 101 of the first mixer 100. At this time, the core precursor solution contains a copper precursor, an indium precursor and a sulfur precursor. Copper iodide (CuI) is used as the copper precursor, indium (In (OAc) ₃ is used as the indium precursor, May be dodecanethiol (DDT).

Next, after the first mixer 100 is formed in a vacuum state, the core precursor solution is heated using the mixer heating unit 104 provided in the first mixer 100. First, the mixture is heated at 120 to 170 DEG C for 10 to 120 minutes, then nitrogen gas is injected through a second inlet 102 existing in the first mixer 100, and the heated core precursor solution is further supplied to 190 to 230 Lt; 0 > C for 1 to 60 minutes to form a core solution. This is cooled to 60 to 100 DEG C to prepare a core solution.

At this time, in the second mixer 200, the shell precursor solution is poured through the fourth inlet 201 of the second mixer 200, and then the mixture is heated in the mixer heating unit 204 provided in the second mixer 200 under vacuum, To heat the shell precursor solution. The shell precursor solution is heated at 100 to 150 ° C for 1 to 60 minutes and then cooled to 60 to 100 ° C.

The core solution produced in the first mixer 100 is supplied into the second mixer 200 through the third inlet 201 connected to the first flow channel 500 and then mixed. At this time, the mixing time is most preferably about 1 to 20 minutes. When the mixing time is more than 20 minutes, the productivity is lowered and large particles are obtained. When the mixing time is less than 1 minute, have.

Next, the mixed solution is supplied to the sintering furnace 400 through the second flow channel 600 connected to the second outlet 203, and the temperature of the mixed solution is heated to 300 to 350 ° C. while passing through the sintering furnace 400 do. Through this, a shell layer is formed and grown on the surface of the core formed in the first mixer 100 to finally obtain a nanocrystal having a core / shell structure.

In this case, the flow rate of the mixed solution is most preferably 1 to 3 mL / min. When the flow rate of the mixed solution is less than 1 mL / min, the synthesis rate is too slow. When the flow rate exceeds 3 mL / Is difficult to secure.

Hereinafter, embodiments of the present invention will be described.

Manufacturing example

0.0476 g of copper iodide (CuI), 0.1460 g of indium acetate, 5 mL of 1-dodecanethiol and 4 mL of 1-octadecene were added through a first inlet of the first mixer to mix do. The mixed core precursor solution in the first mixer is heated at 120 to 170 占 폚 under vacuum for 10 to 120 minutes, and then nitrogen gas is injected through the second inlet. When the heated core precursor solution is heated at 190 to 230 캜 under nitrogen for 1 to 60 minutes, a core solution containing CuInS ₂ is formed. At this time, the core solution is cooled to 60 to 100 캜 to prepare a core solution.

8 mL of trioctylamine, 4 mL of oleic acid and 4 mL of 1-dodecanthiol were added to 1.46 g of zinc acetate through a fourth inlet of the second mixer Mix. And the second mixer is maintained in a vacuum state through the fourth inlet. The second mixer is heated under vacuum to 100 to 150 for 1 to 60 minutes and then cooled to 60 to 100 DEG C to prepare a shell precursor solution.

Next, the core solution prepared in the first mixer is supplied to the second mixer through the first flow channel, and then mixed for 5 to 20 minutes. Thereafter, the mixed solution is supplied to the calcining furnace through the second flow channel. At this time, the flow rate of the mixed solution is 1 mL / min, and the temperature of the mixed solution passing through the firing furnace is 320 ° C. In the course of passing through the firing furnace, a shell of ZnS was formed on the surface of CuInS ₂ nanocrystals present in the core solution to prepare a core / shell structure of CuInS ₂ / ZnS nanocrystals.

FIG. 2A is a graph showing the results of measuring the weight of a CuInS ₂ / ZnS nanocrystal prepared in accordance with the preparation example of the present invention on a balance after drying and drying the CuInS ₂ / ZnS nanocrystal in chloroform. FIG. 2B shows absorption and emission spectra of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention. According to the absorption and emission spectra of CuInS ₂ / ZnS nanocrystals, the absorption peak of CuInS ₂ / ZnS nanocrystals is 455 nm, Can be confirmed to be 561 nm. At this time, the half width of the CuInS ₂ / ZnS nanocrystal was 92 nm and the maximum quantum efficiency was calculated as 61.4%, which indicates that the nanocrystals of the present invention have excellent numerical values.

Figure 3 is a crystal structure of in the XRD (X-ray diffraction) measurement graph of CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the present invention, CuInS ₂ / ZnS nanocrystal CuInS ₂ (JCPDS: 32-0339) and As a result of comparison with ZnS (JCPDS: 10-0434), it was confirmed that the structure of CuInS ₂ / ZnS nanocrystals has a Wurtzite crystal structure due to the influence of the ZnS shell layer, The CuInS ₂ / ZnS nanocrystals obtained by using the crystal manufacturing apparatus indicate that the shell layer is stably formed on the surface of the core.

Figures 4a and 4b are transmission electron microscope (TEM) image of the CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the present invention, Figure 4c of the CuInS ₂ / ZnS nanocrystals prepared according to the Preparation Example of the invention It is a graph obtained using a scanning electron microscope as a result of EDX.

4A-4B, the CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention appear to have monodispersity of uniform size, and the diffraction pattern inserted in the graph of FIG. 4A It can be confirmed that the crystallinity of the CuInS ₂ / ZnS nanocrystals prepared according to the production example is excellent. In addition, it can be confirmed that the CuInS ₂ / ZnS nanocrystals have a size of 4 to 5 nm and a lattice spacing of 0.357 nm to form a uniform structure.

According to FIG. 4C, the ratio of Cu: In is 0.45, and the ratio of CuInS ₂ It was confirmed that the ratio of Cu to In contained in the core was formed similar to the theoretical one. This indicates that the particle size and crystal structure of the CuInS ₂ / ZnS nanocrystals obtained using the manufacturing apparatus according to the present invention are uniform.

5A is an XPS analysis graph of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention, FIG. 5A is an overview spectrum showing Cu, In, S, Zn and S elements, and FIGS. Cu 2p, In 3d, Zn 2p, and S 2p peaks at high resolution.

According to Fig. 5, the oxidation state of each element was found to be +1 for Cu, +3 for +3, -2 for Zn, and -2 for S, and according to the result of analyzing the peak of S, One is S of CuInS ₂ and the other is S of ZnS. From the XPS analysis graph, the stoichiometry of CuInS ₂ / ZnS nanocrystals was calculated. As a result, it was confirmed that the ratio of Cu to In was 0.51, which is 0.5 according to the actually calculated value.

6 is an emission spectrum of CuInS ₂ / ZnS nanocrystals measured at a distance of 10 cm from a UV lamp in a dark environment in order to confirm the optical stability of CuInS ₂ / ZnS nanocrystals prepared according to the preparation example of the present invention. According to the results, there was almost no change in the luminescence intensity within 5% up to 156 hours, and after 25 days CuInS ₂ / ZnS nanocrystals dispersed in chloroform were compared with the photoluminescence spectrum before irradiation, Can be confirmed.

Thus, it can be seen that the light stability of the CuInS ₂ / ZnS nanocrystals produced in large quantities using the manufacturing apparatus of the present invention is excellent, which means that the nanocrystal luminescence property is maintained for a long period of time.

100: first mixer 101: first inlet
102: second inlet port 103: first outlet port
104, 204: mixer heating unit 200: second mixer
201: Third inlet 202: Fourth inlet
203: Second outlet 300: Flow regulating pump
400: firing furnace 500: first flow channel
600: second flow channel

Claims (14)

A first mixer;
A second mixer connected in series with the first mixer;
A sintering furnace connected to the second mixer;
And a flow control pump provided between the calcining furnace and the second mixer. The method according to claim 1,
Wherein the first mixer and the second mixer are connected by a first flow channel, and the second mixer, the baking furnace, and the flow rate control pump are connected by a second flow channel. The method according to claim 1,
And a mixer heating unit for adjusting the temperature of each mixer at a lower end of the first mixer and the second mixer. The method according to claim 1,
The first mixer may include a first inlet through which the core precursor solution is supplied, a second inlet through which a vacuum state or nitrogen gas is supplied, And a first outlet connected to the second mixer through a first flow channel. The method according to claim 1,
The second mixer includes a third inlet through which the core solution is supplied through the first flow channel connected to the first mixer, and a fourth inlet through which the shell precursor solution is supplied; And a second outlet connected to the baking furnace through a second flow channel. 3. The method of claim 2,
The diameter of the first flow channel and the second flow channel is 2.5 to 3.5 mm,
Wherein the length of the first flow channel is 1 to 10 m and the length of the second flow channel is 2 to 20 m. A method for producing CuInS ₂ / ZnS nanocrystals using the apparatus for producing nanocrystals according to claim ₁ ,
I) mixing and heating the core precursor solution supplied to the first mixer to form a core;
II) mixing and heating the shell precursor solution supplied to the second mixer;
III) feeding the core solution formed in step I) to a second mixer heated in step II) and mixing with the shell precursor solution;
Ⅳ) step of the above mixed solution is supplied to the sintering furnace at a constant rate through the flow control pump to give the nanocrystals; method for manufacturing a CuInS ₂ / ZnS nanocrystal comprising a. 8. The method of claim 7,
And then purifying the obtained nanocrystals. The present invention also provides a method for preparing CuInS ₂ / ZnS nanocrystals. 8. The method of claim 7,
Wherein the core precursor solution comprises a copper precursor, an indium precursor and a sulfur precursor,
The shell precursor solution process for producing a CuInS ₂ / ZnS nanocrystal comprising a zinc precursor and the sulfur precursor. 8. The method of claim 7,
Wherein the copper precursor is copper iodide (CuI), the indium precursor is indium acetate (In (OAc) ₃ ), and the sulfur precursor is dodecanethiol (DDT)
Wherein the zinc precursor is zinc stearate or zinc acetate and the sulfur precursor is dodecanethiol. ≪ _{RTI ID = 0.0} > 21. < / RTI > 8. The method of claim 7,
Wherein the step (I) comprises the steps of: (i) heating the first mixer at 120 to 170 DEG C for 10 to 60 minutes; (I-ii) heating the heated first mixer at 190 to 230 DEG C for 1 to 60 minutes; The method of comprising the CuInS ₂ / ZnS nanocrystal; and Ⅰ-ⅲ) step of cooling to 60 to 100 ℃ the heated first mixer. 8. The method of claim 7,
The step II) comprises the steps of: II-i) heating the second mixer to 100 to 150 for 1 to 60 minutes; And II-ii) cooling the heated second mixer to 60-100 ° C. The method for producing CuInS ₂ / ZnS nanocrystals according to claim _1, 8. The method of claim 7,
Wherein the flow rate of the CuInS ₂ / ZnS nanocrystals is adjusted to 1 to 3 mL / min. 8. The method of claim 7,
The calcination furnace is CuInS ₂ / ZnS method of manufacturing a nanocrystal characterized in that the holding at 300 to 350 ℃.

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