WO2018139446A1 - Apparatus for producing semiconductor nanoparticles and method for producing semiconductor nanoparticles - Google Patents

Abstract

An apparatus for producing semiconductor nanoparticles, which is provided with: a spray part which sprays at least one of a liquid (1) that contains at least one of a group 12 element and a group 13 element and a liquid (2) that contains at least one of a group 15 element and a group 16 element; and a reactor to which the other one of the liquid (1) and the liquid (2), which has not been sprayed, is supplied so that droplets of the liquid sprayed by the spray part come into contact with the droplets of the other liquid, thereby mixing the liquid (1) and the liquid (2) with each other so that at least one of the group 12 element and the group 13 element contained in the liquid (1) and at least one of the group 15 element and the group 16 element contained in the liquid (2) are reacted with each other.

Description

Semiconductor nanoparticle manufacturing apparatus and semiconductor nanoparticle manufacturing method

The present invention relates to a semiconductor nanoparticle manufacturing apparatus and a semiconductor nanoparticle manufacturing method.

Semiconductor nanoparticles such as semiconductor quantum dots have excellent fluorescence characteristics and are being applied to displays, lighting, biosensing, and the like. Research on semiconductor quantum dots is also underway as a material that improves the efficiency of solar cells. In particular, a semiconductor quantum dot containing a group 12 element or group 13 element and a group 15 element or group 16 element may be an excellent fluorescent material. Examples of such a semiconductor quantum dot include cadmium selenide. (CdSe) and indium phosphide (InP). Since the fluorescence wavelength of the semiconductor quantum dots changes depending on the particle diameter, the fluorescence wavelength can be controlled by controlling the particle diameter. Therefore, a semiconductor quantum dot manufacturing apparatus and manufacturing method that can be controlled to an arbitrary particle size are required.

Here, for example, a solvothermal method has been proposed as a method for manufacturing semiconductor quantum dots. In this method, a semiconductor quantum dot is synthesized by mixing a metal ion precursor and an anion precursor in a coordinating organic solvent and heating.

In the solvothermal method, for example, indium chloride, trisdimethylaminophosphine, dodecylamine, and toluene are put in a sealed container, sealed with argon, and heated at 180 ° C. for 24 hours while being protected with a stainless steel jacket. Is a method for producing indium phosphide (see, for example, Patent Document 1). In this method, indium phosphide having a wide particle size distribution is obtained, and the fluorescence spectrum also shows a wide shape.

JP 2010-138367 A

For semiconductor nanoparticles produced by the solvothermal method, particle sorting is required to obtain semiconductor nanoparticles having only a specific fluorescence wavelength. Furthermore, the fluorescence peak wavelength of indium phosphide obtained by the solvothermal method is, for example, about 620 nm to 640 nm, and the production efficiency of indium phosphide having a short fluorescence wavelength (eg, 570 nm or less, preferably 550 nm or less) is very high. There is a problem that it is low. This is because when semiconductor nanoparticles are produced by the solvothermal method, it is difficult to control the particle diameter of the semiconductor nanoparticles so that the fluorescence wavelength becomes a short wavelength. Therefore, as an example, in order to efficiently manufacture semiconductor nanoparticles having a short fluorescent wavelength, semiconductor nanoparticle manufacturing apparatuses and semiconductor nanoparticles that can efficiently manufacture semiconductor nanoparticles with a controlled particle diameter are provided. A manufacturing method is desired.

An object of one embodiment of the present invention is to provide a semiconductor nanoparticle manufacturing apparatus and a semiconductor nanoparticle manufacturing method capable of efficiently manufacturing semiconductor nanoparticles with a controlled particle size.

The means for solving the above problems include the following embodiments.

<1> A spray section for spraying one of a liquid (1) containing at least one of a group 12 element and a group 13 element or a liquid (2) containing at least one of a group 15 element and a group 16 element; and the liquid (1) And the other liquid (not sprayed) of the liquid (2) is supplied, and the droplet sprayed by the spraying unit comes into contact with the other liquid, and the liquid (1) and the liquid (2) And a reactor that reacts at least one of group 12 elements and group 13 elements contained in liquid (1) with at least one of group 15 elements and group 16 elements contained in liquid (2). Nanoparticle production equipment.
<2> A spray unit that sprays a liquid (3) containing at least one of group 12 element and group 13 element and at least one of group 15 element and group 16 element, and liquid (4) are supplied, and sprayed by the spray unit The liquid droplet contacts the liquid (4), and the liquid (3) and the liquid (4) are mixed to at least one of the group 12 element and the group 13 element contained in the liquid (3) and the group 15 And a reactor for reacting at least one of an element and a group 16 element.
<3> The semiconductor nanoparticle production apparatus according to <1> or <2>, wherein the spraying is performed by electrospray.
<4> At least a part of the spray unit, or at a position where the first electrode attached to at least a part of the spray unit is in contact with the liquid when the liquid is supplied to the reactor. The semiconductor nanoparticle manufacturing apparatus according to <3>, further comprising: a second electrode that is arranged; and a potential difference forming unit that forms a potential difference between the first electrode and the second electrode.
<5> The semiconductor nanoparticle manufacturing apparatus according to <4>, wherein the second electrode is a ring-shaped, cylindrical, mesh-shaped, rod-shaped, spherical, hemispherical, or plate-shaped conductor.
<6> The semiconductor nanoparticle manufacturing apparatus according to <4> or <5>, wherein the potential difference forming unit forms a potential difference of 0.3 kV to 30 kV in absolute value.
<7> The semiconductor nanoparticle manufacturing apparatus according to any one of <1> to <6>, wherein a diameter of a droplet sprayed from the spraying unit is 0.1 μm to 100 μm.
<8> The semiconductor nanoparticle manufacturing apparatus according to any one of <1> to <7>, wherein an inner diameter of the spraying part is 0.01 mm to 1 mm.
<9> The semiconductor according to any one of <1> to <8>, wherein a liquid feeding speed of the sprayed liquid from the spraying unit is 0.001 mL / min to 1 mL / min per one spraying unit. Nanoparticle production equipment.
<10> The semiconductor nanoparticle production apparatus according to any one of <1> to <9>, further comprising a heating unit that heats the reactor.
<11> The semiconductor nanoparticle manufacturing apparatus according to <10>, wherein the heating unit is a thermal fluid, a solid heat medium, or a heating wire.
<12> The semiconductor nanoparticle production apparatus according to any one of <1> to <11>, further comprising an inert gas supply unit that supplies an inert gas into the reactor.
<13> A material supply unit that supplies the reactor with a material that forms a layer that covers at least a part of the core particles and the surface of the core particles produced in the reactor, and the reactor supplies the material. The semiconductor nanoparticle manufacturing apparatus according to any one of <1> to <12>, wherein a layer covering at least a part of the surface of the core particle is formed.
<14> A forming device for supplying a core particle produced in the reactor and a material for forming a layer covering at least a part of the surface of the core particle to form a layer covering at least a part of the surface of the core particle. The semiconductor nanoparticle production apparatus according to any one of <1> to <12>, further comprising:
<15> A method for producing semiconductor nanoparticles, comprising producing semiconductor nanoparticles using the semiconductor nanoparticle production apparatus according to any one of <1> to <14>.

According to one embodiment of the present invention, it is possible to provide a semiconductor nanoparticle manufacturing apparatus and a semiconductor nanoparticle manufacturing method capable of efficiently manufacturing semiconductor nanoparticles having a controlled particle diameter.

It is the schematic which shows the semiconductor nanoparticle manufacturing apparatus of 1st Embodiment. It is the schematic which shows the semiconductor nanoparticle manufacturing apparatus of the modification 1 of 1st Embodiment. It is the schematic which shows the semiconductor nanoparticle manufacturing apparatus of 2nd Embodiment. It is a graph which shows the result of the fluorescence spectrum measurement in Example 6. 10 is a graph showing the results of fluorescence spectrum measurement in Examples 7 to 9. It is a graph which shows the result of the fluorescence spectrum measurement in Comparative Examples 2 and 3. It is a graph which shows the result of the fluorescence spectrum measurement in Example 4 and 5.

Hereinafter, embodiments for carrying out the present invention will be described in detail. However, the present invention is not limited to the following embodiments. In the following embodiments, the components (including element steps and the like) are not essential unless otherwise specified. The same applies to numerical values and ranges thereof, and the present invention is not limited thereto.

In the present disclosure, numerical ranges indicated using “to” include numerical values described before and after “to” as the minimum value and the maximum value, respectively.
In the numerical ranges described stepwise in the present disclosure, the upper limit value or the lower limit value described in one numerical range may be replaced with the upper limit value or the lower limit value of another numerical description. . Further, in the numerical ranges described in the present disclosure, the upper limit value or the lower limit value of the numerical range may be replaced with the values shown in the examples.
In the present disclosure, when an embodiment is described with reference to the drawings, the configuration of the embodiment is not limited to the configuration shown in the drawings. Moreover, the magnitude | size of the member in each figure is notional, The relative relationship of the magnitude | size between members is not limited to this.

<First Embodiment>
[Semiconductor nanoparticle production equipment]
Hereinafter, the semiconductor nanoparticle manufacturing apparatus 100 according to the first embodiment of the present invention will be described with reference to FIG. The semiconductor nanoparticle manufacturing apparatus 100 includes a liquid (1) including at least one of a group 12 element and a group 13 element (hereinafter also referred to as “liquid (1)”) or at least one of a group 15 element and a group 16 element. A nozzle 1 (spraying part) for spraying one of the liquids (2) (hereinafter also referred to as “liquid (2)”) and the other liquid not sprayed of the liquids (1) and (2). The liquid droplets supplied and sprayed by the nozzle 1 come into contact with the other liquid, and the liquid (1) and the liquid (2) are mixed to at least one of the group 12 element and the group 13 element contained in the liquid (1). And a reactor 6 for reacting at least one of the group 15 element and the group 16 element contained in the liquid (2).

Moreover, the semiconductor nanoparticle manufacturing apparatus 100 includes an inert gas supply pipe 21 (inert gas supply unit) that supplies an inert gas into the reactor 6.
Moreover, the semiconductor nanoparticle manufacturing apparatus 100 is provided with a counter electrode 4 that functions as a second electrode and a counter electrode 4 that functions as a second electrode in a reactor 6 together with a nozzle 1 that is metal-plated on the outer peripheral portion. And a power source 5 (potential difference forming unit) for forming a potential difference between the two. The nozzle 1 may be a metal-plated glass thin tube, a stainless steel hollow needle, a stainless steel tube, or the like. Further, the nozzle 1 may be a nozzle provided with an internal electrode functioning as a first electrode in a flow path made of a non-conductive material.
Furthermore, the semiconductor nanoparticle manufacturing apparatus 100 includes a thermal fluid 8 (heating unit) that heats the reactor 6.
Furthermore, the semiconductor nanoparticle manufacturing apparatus 100 includes a cooling pipe 7 that cools the volatilized components in the reactor 6 and returns them to the reaction field.

In the semiconductor nanoparticle manufacturing apparatus 100 of the present disclosure, one of the liquid (1) containing at least one of the group 12 element and the group 13 element or the liquid (2) containing at least one of the group 15 element and the group 16 element is used as the reactor 6. And the sprayed droplets are brought into contact with the other liquid (1) and the liquid (2) which are not sprayed. When both liquids are brought into contact and mixed, at least one of the Group 12 element and Group 13 element contained in the liquid (1) reacts with at least one of the Group 15 element and Group 16 element contained in the liquid (2). Thus, semiconductor nanoparticles are manufactured. Since the semiconductor nanoparticles are produced by bringing the sprayed droplets, which are one of the liquid (1) and the liquid (2), into contact with the other liquid, the produced semiconductor nanoparticles are compared with the solvothermal method. Control of the particle diameter of the particles is easy, and semiconductor nanoparticles with controlled particle diameter can be efficiently produced.

Since the control of the particle diameter of the manufactured semiconductor nanoparticles is easy, the control of the fluorescence wavelength of the manufactured semiconductor nanoparticles (particularly, the control of the fluorescence wavelength on the short wavelength side) tends to be easy. Therefore, for example, semiconductor nanoparticles having a long fluorescence peak wavelength to a short wavelength can be efficiently produced, and semiconductor nanoparticles having a desired fluorescence peak wavelength tend to be efficiently produced.
In addition, for example, semiconductor nanoparticles having a short fluorescent wavelength (for example, 570 nm or less, preferably 550 nm or less) tend to be efficiently produced.

In the present disclosure, “semiconductor nanoparticles” mean particles having an average particle diameter of 1 nm to 100 nm. The average particle diameter of the semiconductor nanoparticles is the particle diameter (D50) when the accumulation from the small diameter side becomes 50% in the volume-based particle size distribution measured by the laser diffraction method.

In the present disclosure, the shape of the “semiconductor nanoparticle” is not particularly limited, and may be spherical, oval, flake, rectangular parallelepiped, columnar, irregular, etc., spherical, oval, flake, rectangular A part of the shape, columnar shape or the like may be an irregular shape.

In the present disclosure, the “semiconductor nanoparticles” may include at least one of a group 12 element and a group 13 element and at least one of a group 15 element and a group 16 element. In addition, for example, in the manufacturing process of semiconductor nanoparticles, included in a dispersant, other organic solvent, a compound containing at least one of group 12 element and group 13 element, a compound containing at least one of group 15 element and group 16 element, etc. May be mixed with atoms and molecules.

The liquid (1) containing at least one of the group 12 element and the group 13 element used in the semiconductor nanoparticle manufacturing apparatus 100 may be a liquid containing a component containing at least one of the group 12 element and the group 13 element. Examples of the component containing at least one of the group 12 element and the group 13 element include a group 12 metal, a group 13 metal, a group 12 metal compound, a group 13 metal compound, a compound containing a group 12 metal and a group 13 metal, and the like.

Examples of the group 12 element include group 12 metals such as zinc (Zn), cadmium (Cd), mercury (Hg), etc. Among them, zinc (Zn) and cadmium (Cd) are preferable.

Examples of the group 13 element include group 13 metals such as aluminum (Al), gallium (Ga), indium (In), and thallium (Tl), among which indium (In) is preferable.

The group 12 metal compound is not particularly limited as long as it contains a group 12 metal. Halides such as chloride, bromide, iodide, etc., oxides, nitrides, sulfides, hydroxides, including group 12 metals. Products, organic salts such as acetates, and organic complexes. Among these, a halide containing a group 12 metal is preferable, and indium chloride is more preferable because it is highly reactive with a phosphorus compound (for example, trisdimethylaminophosphine).

More specifically, examples of the cadmium compound that is a Group 12 metal compound include cadmium halides such as cadmium chloride, cadmium bromide, and cadmium iodide, cadmium oxide, cadmium hydroxide, cadmium acetate, and cadmium acetylacetonate. Among these, cadmium oxide is preferable because it is relatively stable, has a low hygroscopicity as compared with cadmium halide, and is easy to handle.

The group 13 metal compound is not particularly limited as long as it contains a group 13 metal, and includes halides such as chloride, bromide, iodide, etc., oxides, nitrides, sulfides, hydroxides, including group 13 metals. Products, alkoxides and the like.

More specifically, examples of indium compounds that are Group 13 metal compounds include indium halides such as indium chloride, indium bromide, and indium iodide, indium oxide, indium nitride, indium sulfide, indium hydroxide, indium acetate, and indium. Examples thereof include isopropoxide, and among them, indium chloride is preferable because it is highly reactive with a phosphorus compound (for example, trisdimethylaminophosphine) and has a relatively low market price.

The liquid (1) preferably contains a dispersant from the viewpoint of suppressing aggregation of a component containing at least one of the group 12 element and the group 13 element in the liquid. As the dispersant, a coordinating organic solvent is preferable. Specifically, organic amines such as dodecylamine, tetradecylamine, hexadecylamine, oleylamine, trioctylamine, eicosylamine, lauric acid, capron Acids, myristic acid, palmitic acid, fatty acids such as oleic acid, and organic phosphine oxides such as trioctyl phosphine oxide, among others, have excellent reactivity with phosphorus compounds and promote the generation of indium phosphide. Also, oleylamine is preferred because it has a high boiling point and is difficult to volatilize during high-temperature synthesis. Moreover, oleic acid is preferable from the viewpoint of high solubility of cadmium oxide.

When the liquid (1) contains a dispersant, the total content of components containing at least one of group 12 elements and group 13 elements with respect to 1 mL of the dispersant is preferably 0.01 g to 0.2 g. The amount is more preferably 03 g to 0.15 g, and further preferably 0.04 g to 0.10 g.

Liquid (1) may contain other organic solvents. Other organic solvents include aliphatic saturated hydrocarbons such as n-hexane, n-heptane, n-octane, n-nonane, n-decane, n-dodecane, n-hexadecane, n-octadecane, 1-undecene, Examples thereof include aliphatic unsaturated hydrocarbons such as 1-dodecene, 1-hexadecene and 1-octadecene, and trioctylphosphine.

The liquid (2) containing at least one of the group 15 element and the group 16 element used in the semiconductor nanoparticle manufacturing apparatus 100 may be a liquid containing a component containing at least one of the group 15 element and the group 16 element. Examples of the component containing at least one of group 15 element and group 16 element include group 15 element simple substance, group 15 element compound, group 16 element simple substance, group 16 element compound, compound containing group 15 element and group 16 element, and the like. .

Examples of the group 15 element include nitrogen (N), phosphorus (P), arsenic (As), antimony (Sb), bismuth (Bi), etc. Among them, phosphorus (P) is preferable.

Examples of the group 16 element include oxygen (O), sulfur (S), selenium (Se), tellurium (Te), polonium (Po), etc. Among them, sulfur (S) and selenium (Se) are preferable.

Examples of the group 15 element compound include compounds containing phosphorus, specifically, trisdimethylaminophosphine, trisdiethylaminophosphine, tristrimethylsilylphosphine, phosphine (PH ₃ ) and the like. Trisdimethylaminophosphine is preferred because it is highly reactive, has a high boiling point and is suitable for high-temperature synthesis, and has low toxicity compared to silyl-based phosphorus compounds.

Examples of group 16 element compounds include compounds containing sulfur or selenium, and specific examples include dodecanethiol, selenurea, diethyl selenide, diphenyl selenide, dimethyl selenide, selenium chloride, and benzene selenol.

The liquid (2) used in the semiconductor nanoparticle manufacturing apparatus 100 is obtained by dissolving a solid component in a dispersant, other organic solvent or the like when the component containing at least one of the group 15 element and the group 16 element is a solid. It may be. The liquid (2) may be a liquid component alone or a mixture of a liquid component with a dispersant, other organic solvent, etc., when the component containing at least one of the group 15 element and the group 16 element is a liquid. Good.

Examples of the dispersant include those used in the liquid (1) described above. Moreover, the liquid (2) may contain the above-mentioned other organic solvent like the above-mentioned liquid (1).

In the semiconductor nanoparticle manufacturing apparatus 100, at least one of the group 12 element and the group 13 element contained in the liquid (1) reacts with at least one of the group 15 element and the group 16 element contained in the liquid (2), and the semiconductor nanoparticle is reacted. Particles are produced. Therefore, the semiconductor nanoparticles manufactured using the semiconductor nanoparticle manufacturing apparatus 100 are particles that include at least one of a group 12 element and a group 13 element and at least one of a group 15 element and a group 16 element. It is not limited.

As semiconductor nanoparticles manufactured using the semiconductor nanoparticle manufacturing apparatus 100, CdS, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, HgSe, HgTe, InN, InP, InSb, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb and the like can be mentioned, among which CdSe and InP are preferable.

Hereinafter, each structure of the semiconductor nanoparticle manufacturing apparatus 100 and the process of manufacturing semiconductor nanoparticles using the semiconductor nanoparticle manufacturing apparatus 100 will be described.

The nozzle 1 is a spraying part that is disposed inside the reactor 6 and sprays one of the liquid (1) and the liquid (2). The nozzle 1 is connected to a sprayed liquid supply source 2 via a supply pipe 3. Therefore, the liquid to be sprayed is supplied from the supply source 2 to the nozzle 1 through the supply pipe 3, and the liquid is sprayed from the spray port 1 a of the nozzle 1.

Further, the nozzle 1 is metal-plated at the outer peripheral portion and functions as a first electrode. In addition, the 1st electrode may comprise at least one part of the nozzle 1 which is a spraying part, or may be attached to at least one part of the nozzle 1. FIG.
The nozzle 1 may be a metal-plated glass thin tube, a stainless steel hollow needle, a stainless steel tube, or the like. Further, the nozzle 1 may be a nozzle provided with an internal electrode functioning as a first electrode in a flow path made of a non-conductive material.

Inside the reactor 6, a counter electrode 4 as a second electrode is disposed at a distance from the nozzle 1. The spray port 1a of the nozzle 1 is preferably disposed so as to face a part of the counter electrode 4, and the spray port 1a of the nozzle 1 sprays liquid in a direction intersecting the plane of the counter electrode 4. It is more preferable that they are arranged as described above.
The counter electrode 4 may be disposed in contact with the bottom portion in the reactor 6 or may be disposed away from the bottom portion in the reactor 6.

Examples of the shape of the counter electrode 4 include a ring shape, a cylindrical shape, a mesh shape, a rod shape, a spherical shape, a hemispherical shape, and a plate shape. When the shape of the counter electrode 4 is a ring shape or a cylindrical shape, the counter electrode 4 may be disposed along the circumferential direction of the reactor 6.

Moreover, the semiconductor nanoparticle manufacturing apparatus 100 includes a power source 5 that forms a potential difference between the nozzle 1 and the counter electrode 4. The power source 5 is preferably a high voltage power source. The power source 5 may be configured such that the nozzle 1 has a positive potential and the counter electrode 4 has a lower potential than the nozzle 1, the nozzle 1 has a negative potential, and the counter electrode 4 has a higher potential than the nozzle 1. You may be comprised so that it may become an electric potential.

Thereby, the semiconductor nanoparticle production apparatus 100 can perform spraying of at least one of the liquid (1) and the liquid (2) by electrospray, and can suitably control the particle diameter of the semiconductor nanoparticles, There is a tendency that semiconductor nanoparticles having a desired fluorescence peak wavelength can be produced more efficiently.

In the present disclosure, “electrospray” refers to a device that forms an electric field by applying a voltage between electrodes and sprays the liquid by Coulomb force, or a state in which the liquid is sprayed by the device.

As shown in FIG. 1, in the semiconductor nanoparticle manufacturing apparatus 100, the counter electrode 4 is disposed at a position away from the spray port 1 a of the nozzle 1 by W1 + W2. W1 is the distance between the liquid level of the stored liquid and the spray port 1a of the nozzle 1 when the other liquid of the liquid (1) and the liquid (2) that is not sprayed is stored in the reactor 6. To express. W2 represents the distance between the counter electrode 4 and the liquid level of the liquid stored when the other liquid (1) and liquid (2) that are not sprayed are stored in the reactor 6. .

The distance W1 + W2 between the spray port 1a of the nozzle 1 and the counter electrode 4 affects the electric field strength, the diameter and shape of the droplet generated by electrospray, and is preferably adjusted as appropriate.

The distance W1 + W2 between the spray port 1a of the nozzle 1 and the counter electrode 4 is preferably, for example, 3 mm to 300 mm, more preferably 10 mm to 250 mm, and further preferably 15 mm to 200 mm.

The distance W1 is preferably 2 mm to 100 mm, more preferably 5 mm to 70 mm, and still more preferably 10 mm to 50 mm, from the viewpoint of suppressing fluctuation of the shape of the sprayed droplets.

The inner diameter of the nozzle 1 is preferably 0.01 mm to 1 mm, more preferably 0.1 mm to 0.8 mm from the viewpoint of more efficiently producing semiconductor nanoparticles having a short fluorescent wavelength. More preferably, it is 0.3 to 0.7 mm.

The diameter of the droplet sprayed from the nozzle 1 is preferably 0.1 μm to 100 μm, more preferably 1 μm to 50 μm, from the viewpoint of more efficiently producing semiconductor nanoparticles having a short fluorescent wavelength. More preferably, it is 1 μm to 10 μm. By mixing the liquid (1) and the liquid (2) by bringing the droplet to be sprayed into contact with the other liquid not sprayed by setting the diameter of the sprayed droplet to be within the above-mentioned numerical range. The temperature change of the liquid can be suppressed, and the temperature of the droplet sprayed in a short time can be set to the same temperature as the other liquid not sprayed. Therefore, the temperature change of the reaction field is small, and the particle diameter of the semiconductor nanoparticles can be controlled more appropriately. For example, semiconductor nanoparticles having a short fluorescence wavelength tend to be produced more efficiently. It is in.
Further, by setting the diameter of the droplet to be sprayed within the above-mentioned numerical range, the droplet to be sprayed is rapidly mixed when it comes into contact with the other liquid not sprayed. Therefore, the reaction time between at least one of the group 12 element and group 13 element contained in the liquid (1) and at least one of the group 15 element and group 16 element contained in the liquid (2) is shortened, and the particle size can be reduced in a short time. Controlled semiconductor nanoparticles can be produced.
The diameter of the droplet to be sprayed is adjusted by, for example, adjusting the nozzle diameter, adjusting the liquid feeding speed, surface tension, viscosity, ionic strength and relative dielectric constant of the liquid to be sprayed, or spraying by electrospray. In this case, it is possible to adjust the voltage appropriately by adjusting the voltage or adjusting the kind of the inert gas.

The liquid feeding speed of the liquid sprayed from the nozzle 1 is preferably 0.001 mL / min to 1 mL / min, more preferably 0.01 mL / min to 0.1 mL / min, and 0.02 mL / min. More preferably, it is from min to 0.05 mL / min.
For example, when spraying a droplet from one nozzle, it is preferable that the liquid feeding speed in the nozzle satisfies the above numerical range. Further, when spraying droplets from a plurality of nozzles, it is preferable that the liquid feeding speeds of the plurality of nozzles all satisfy the above-described numerical range.

After spraying of the droplets from the nozzle 1 is completed, the group 12 elements and 13 in the liquid containing at least one of the group 12 elements and the group 13 elements and at least one of the group 15 elements and the group 16 elements in the reactor 6 From the source 2 to the nozzle 1 so that the molar ratio (A: B) of A which is at least one of group elements and B which is at least one of group 15 elements and group 16 elements becomes a predetermined numerical value. It is preferable to adjust the supply of liquid and the spraying of droplets from the nozzle 1. The above-mentioned A: B is preferably 1: 1 to 1:16 from the viewpoint of more efficiently producing semiconductor nanoparticles having a short fluorescent wavelength, and semiconductor nanoparticles having a narrow particle size distribution are preferably used. From the viewpoint of efficient production, it is more preferably more than 1: 2 and less than 1: 8, more preferably 1: 3 to 1: 7, and particularly preferably 1: 4 to 1: 6. .

The inert gas supply pipe 21 is an inert gas supply unit that supplies an inert gas into the reactor 6. In the semiconductor nanoparticle manufacturing apparatus 100, at least one of the liquid (1) and the liquid (2) is sprayed in an inert gas, and the sprayed liquid droplets are sprayed from the liquid (1) and the liquid (2). Contact the other liquid that is not. Thereby, mixing of oxygen, water vapor or the like into the manufactured semiconductor nanoparticles is suppressed, defects of the semiconductor nanoparticles tend to be suppressed, and a decrease in fluorescence efficiency of the semiconductor nanoparticles tends to be suppressed.
Examples of the inert gas include nitrogen, argon, carbon dioxide, sulfur hexafluoride (SF ₆ ), and a mixed gas thereof.
Moreover, you may distribute | circulate an inert gas in the reactor 6 by the gas flow rate of arbitrary values of 0 L / min more than 10 L / min per inert gas supply pipe | tube.
Further, when the other liquid not sprayed in the reactor 6 is supplied, the tip of the inert gas supply pipe 21 may be disposed in the other liquid. Thereby, when supplying an inert gas in the reactor 6, removal of the volatile impurity which may be contained in the other liquid tends to be promoted. Furthermore, when the droplet sprayed on the other liquid is brought into contact, it is preferable to stop the supply of the inert gas into the reactor 6 from the viewpoint of suppressing a decrease in the production efficiency of the semiconductor nanoparticles.
Moreover, the structure which installs a nozzle inside an inert gas supply pipe instead of the structure which arrange | positions the inert gas supply pipe | tube 21 and the nozzle 1 separately (double pipe structure) may be sufficient, for example.

The power source 5 preferably forms a potential difference of 0.3 kV to 30 kV in absolute value between the nozzle 1 and the counter electrode 4, and more preferably forms a potential difference of 1.0 kV to 10 kV.
The power source 5 has an absolute value of 2.0 kV from the viewpoint of more efficiently producing semiconductor nanoparticles having a short fluorescence wavelength, particularly more efficiently producing semiconductor nanoparticles having a fluorescence wavelength of 500 nm to 550 nm. It is preferable to form a potential difference of ˜8.0 kV.
From the viewpoint of efficiently producing semiconductor nanoparticles having a narrow particle size distribution, the power source 5 preferably forms a potential difference of more than 4.0 kV and less than 8.0 kV in absolute value, and 5.0 kV to 7.k in absolute value. It is more preferable to form a potential difference of 0 kV.

The potential on the nozzle 1 side is preferably -30 kV to 30 kV, and the potential on the counter electrode 4 side is preferably -30 kV to 30 kV.

A voltage is applied to the nozzle 1 and the counter electrode 4 by the power source 5, and the micro droplet L 1 is sprayed from the spray port 1 a of the nozzle 1 in a state where an electrostatic field is formed between the nozzle 1 and the counter electrode 4. Thereby, the micro droplet L1 moves toward the liquid L2 along the electric field gradient in a charged state, and comes into contact with the liquid surface of the liquid L2. When both liquids are brought into contact and mixed, at least one of the Group 12 element and Group 13 element contained in the liquid (1) reacts with at least one of the Group 15 element and Group 16 element contained in the liquid (2). Thus, semiconductor nanoparticles are manufactured. The manufactured semiconductor nanoparticles are dispersed in the liquid L2 to obtain a semiconductor nanoparticle dispersion.
For example, after adding toluene to the dispersion liquid taken out from the reactor 6, methanol was gradually added, and the semiconductor nanoparticles produced were separated by centrifuging the precipitated suspended solids. Semiconductor nanoparticles may be collected.

The thermal fluid 8 is a heating unit that heats the reactor 6. By heating the reactor 6 when manufacturing semiconductor nanoparticles, semiconductor nanoparticles tend to be manufactured more efficiently.

The heating temperature of the reactor 6 is not particularly limited, and is preferably 80 ° C. to 350 ° C. From the viewpoint of more efficiently producing semiconductor nanoparticles having a short fluorescence wavelength, the heating temperature is 100 ° C. to 220 ° C. More preferably, it is 120 ° C. to 190 ° C.

The heating unit includes a thermal fluid, a solid heat medium, a heating wire, and the like, and more specifically, an oil bath, an aluminum bath, a mantle heater, an electric furnace, an infrared furnace, and the like.

<Modification 1>
The semiconductor nanoparticle production apparatus of the present disclosure may further include a stirring unit that stirs the liquid stored in the reactor 6. Moreover, the inert gas supply part in the semiconductor nanoparticle manufacturing apparatus of this indication may further be equipped with the decompression means which decompresses the inside of a reactor.

FIG. 2 shows a semiconductor nanoparticle manufacturing apparatus 200 that is Modification 1 of the semiconductor nanoparticle manufacturing apparatus 100 of the first embodiment. As shown in FIG. 2, the semiconductor nanoparticle manufacturing apparatus 200 includes a stirrer 11 and a magnetic stirrer 12 as a stirring unit for stirring the liquid stored in the reactor 6. Furthermore, the semiconductor nanoparticle manufacturing apparatus 200 includes a vacuum pump 13 as a decompression unit, and the valve 10 can switch between decompression in the reactor 6 and supply of inert gas into the reactor 6.

As shown in FIG. 2, when spraying is performed by electrospraying, the spraying is not limited to a configuration in which a potential difference is applied between the nozzle 1 and the counter electrode 4, and the intermediate electrode 9 having a ring shape or the like is connected to the nozzle 1. It may be configured so as to be installed between the counter electrode 4 and give a potential difference to the intermediate electrode 9 and the counter electrode 4 at the bottom of the container.

<Modification 2>
The semiconductor nanoparticle manufacturing apparatus of the present disclosure includes a liquid (3) including at least one of a group 12 element and a group 13 element and at least one of a group 15 element and a group 16 element (hereinafter, also referred to as “liquid (3)”). The liquid (4) is supplied, the droplet sprayed by the spraying unit comes into contact with the liquid (4), the liquid (3) and the liquid (4) are mixed, and the liquid (3) And a reactor that reacts at least one of the group 12 element and the group 13 element and at least one of the group 15 element and the group 16 element contained in the reactor. In the semiconductor nanoparticle production apparatus of Modification 2, the liquid sprayed from the spray section includes at least one of Group 12 element and Group 13 element and at least one of Group 15 element and Group 16 element. This is different from the semiconductor nanoparticle manufacturing apparatus 100 of the first embodiment. Also in this modification, semiconductor nanoparticles with a controlled particle diameter can be efficiently produced.
Below, it demonstrates centering on the matter which is different from the above-mentioned 1st Embodiment, and abbreviate | omits the description about the matter similar to 1st Embodiment.

The liquid (3) preferably contains the above-mentioned dispersant from the viewpoint of suppressing aggregation of a component containing at least one of the group 12 element and the group 13 element in the liquid.

When the liquid (3) contains a dispersant, the total content of the component containing at least one of the group 12 element and the group 13 element and the component containing at least one of the group 15 element and the group 16 element with respect to 1 mL of the dispersant is 0. It is preferably 0.01 to 0.2 g, more preferably 0.03 to 0.15 g, and still more preferably 0.04 to 0.10 g.

Liquid (4) is not particularly limited, and may include the above-described dispersant, other organic solvents, and the like.

<Modification 3>
The semiconductor nanoparticle manufacturing apparatus of the present disclosure includes a core particle including at least one of a group 12 element and a group 13 element and at least one of a group 15 element and a group 16 element, and a layer (shell) covering at least a part of the surface of the core particle. The apparatus which manufactures the semiconductor nanoparticle which has a layer) may be sufficient. Semiconductor nanoparticles having a core-shell structure tend to have higher quantum efficiency and a narrower particle size distribution. The core particles correspond to the semiconductor nanoparticles produced in the first embodiment described above.
The shell layer formed on at least a part of the surface of the core particle may have a single layer structure or a multilayer structure (core multishell structure).

The semiconductor nanoparticle production apparatus of the present disclosure further includes a material supply unit that supplies a material for forming a layer covering at least a part of the surface of the core particle to the reactor in terms of producing semiconductor nanoparticles having a core-shell structure, You may form the layer which covers at least one part of the core particle surface with a reactor.

As a material for forming a layer covering at least a part of the surface of the core particle, a material (1) containing at least one of a group 12 element and a group 13 element (hereinafter also referred to as “material (1)”), and a group 15 are used. The combination with the material (2) (henceforth "material (2)") containing at least one of an element and a group 16 element is mentioned. Specific examples of at least one of the group 12 element and the group 13 element contained in the material (1) and at least one of the group 15 element and the group 16 element contained in the material (2) are the same as those described above.

The material supply unit may be configured to supply the material (1) and the material (2) to the reactor, for example.

In addition, from the viewpoint of higher quantum efficiency, it is possible to select the material (1) and the material (2) so that the band gap of the compound constituting the shell layer is wider than the band gap of the compound constituting the core particle. preferable. As combinations of core particles and shell layers (core particles / shell layers), InP / CdS, InP / CdTe, InP / ZnS, InP / ZnSe, InP / ZnTe, CdSe / ZnS, CdSe / CdS, CdTe / CdS, CdTe / ZnS and the like.

The method for forming the shell layer on at least a part of the core particle surface is not particularly limited. For example, after the core particles are formed in the reactor as described above, the materials (1) and (2) are respectively supplied to the liquid containing the particles in the reactor, and the solvent is further added as necessary. Then, the liquid may be heated while stirring. Thereby, the semiconductor nanoparticle which has a shell layer in at least one part of the core particle surface can be manufactured.

In the case where the Group 12 element forming the shell layer is zinc, examples of the zinc source include zinc compounds, and more specifically zinc halides such as zinc stearate and zinc chloride. .
When the group 16 element forming the shell layer is sulfur, examples of the sulfur source include sulfur compounds, more specifically thiols such as dodecanethiol and tetradecanethiol, and dihexyl sulfide. And sulfides. In addition, what dissolved sulfur in trioctylphosphine is good also as a supply source of sulfur.
Examples of the solvent used as necessary include the above-mentioned other organic solvents. Among them, 1-octadecene is preferable.

When forming the shell layer on at least a part of the surface of the core particle, the reaction temperature is preferably 150 ° C. to 350 ° C., more preferably 150 ° C. to 300 ° C., and the reaction time is 1 hour to 200 hours. It is preferably 2 hours to 100 hours, more preferably 3 hours to 25 hours.

Second Embodiment
[Semiconductor nanoparticle production equipment]
Hereinafter, the semiconductor nanoparticle manufacturing apparatus 300 according to the second embodiment of the present invention will be described with reference to FIG. The semiconductor nanoparticle manufacturing apparatus 300 is an apparatus for continuously manufacturing semiconductor nanoparticles having a core-shell structure.

The semiconductor nanoparticle manufacturing apparatus 300 includes a plurality of nozzles 1 that spray one liquid into the reactor 36, a supply pipe 31 and a supply source 32 that supply the other liquid into the reactor 36, and a reactor 36. A shell formation reactor 34 (former) is provided which forms a shell layer on at least a part of the surface of the core particle to be produced.

The semiconductor nanoparticle production apparatus 300 includes a plurality of nozzles 1 for spraying a liquid into the reactor 36. Therefore, the production efficiency of the core particles produced in the reactor 36 tends to be excellent.

The semiconductor nanoparticle production apparatus 300 includes a supply pipe 31 and a supply source 32 that supply the other liquid not sprayed in the reactor 36. The other liquid supplied from the supply pipe 31 flows through the reactor 36 and then is supplied to the shell-forming reactor 34 through the distribution pipe 33.

The reactor 36 is connected to the supply pipe 31 and the distribution pipe 33. The other liquid supplied from the supply pipe 31 flows through the reactor 36 and is then discharged from the distribution pipe 33.

In the reactor 36, it is preferable to spray droplets from the plurality of nozzles 1 while circulating the other liquid from the supply source 32, and bring the sprayed liquid into contact with the other liquid. When both liquids are brought into contact with each other and mixed, at least one of the group 12 element and the group 13 element reacts with at least one of the group 15 element and the group 16 element to form core particles. The core particles produced in the reactor 36 circulate in the reactor 36 together with the other liquid, and then are supplied to the shell-forming reactor 34 through the circulation pipe 33. Can be manufactured continuously.

The semiconductor nanoparticle production apparatus 300 includes a shell formation reactor 34 that forms a shell layer on at least a part of the surface of the core particles produced in the reactor 36. The shell formation reactor 34 is an apparatus that is supplied with a material for forming a layer covering the core particles and at least a part of the surface of the core particles, and forms a shell layer on at least a part of the surface of the core particles.

As shown in FIG. 3, the semiconductor nanoparticle manufacturing apparatus 300 may include two shell formation reactors 34 in parallel. For example, one shell formation reactor 34 forms a core-shell structure. Sometimes, the core particles supplied from the reactor 36 through the flow pipe 33 are collected in the other shell-forming reactor 34, and the two shell-forming reactors 34 produce semiconductor nanoparticles having a core-shell structure alternately. It may be.

When the shell layer is formed on at least a part of the core particle surface in the shell forming reactor 34, the reaction temperature is preferably 150 ° C. to 350 ° C., more preferably 150 ° C. to 300 ° C., and the reaction time. Is preferably 1 hour to 200 hours, more preferably 2 hours to 100 hours, and even more preferably 3 hours to 25 hours.

Moreover, in the semiconductor nanoparticle manufacturing apparatus 300, a configuration in which a core-shell structure is manufactured in the reactor 36 instead of providing the shell-forming reactor 34 may be used.

The semiconductor nanoparticle production apparatus of the present disclosure can be applied to the production of fluorescent materials for various liquid crystal displays, and further can be applied to the production of various electronic devices equipped with a liquid crystal display. Moreover, the semiconductor nanoparticle manufactured using the semiconductor nanoparticle manufacturing apparatus of this indication can anticipate application to bioimaging, a solar cell, etc.

Further, a manufacturing method for manufacturing semiconductor nanoparticles using the semiconductor nanoparticle manufacturing apparatus of the present disclosure is also included in the scope of the present invention.

Hereinafter, the present invention will be specifically described with reference to examples, but the scope of the present invention is not limited to these examples.

[Examples 1 to 5]
After synthesizing indium phosphide by electrospray with the voltage shown in Table 1 using the manufacturing apparatus of the first embodiment described above, and forming an outer shell (shell layer) of zinc sulfide on the surface of the synthesized indium phosphide The fluorescence spectrum was measured. Indium chloride and trisdimethylaminophosphine were used as raw materials, and oleylamine was used as a dispersant.

This example was performed as follows. First, 0.3 g of indium chloride was weighed into a glass reaction vessel, and 5 mL of oleylamine was added and mixed. This operation was performed under a dry nitrogen atmosphere in order to prevent moisture absorption of indium chloride. Subsequently, while flowing nitrogen through the reaction vessel, the mixture was heated to 120 ° C. in an oil bath to dissolve indium chloride in oleylamine. Subsequently, the reaction vessel was heated to 180 ° C. with an oil bath, and 1.05 mL (0.050 mL / min) of trisdimethylaminophosphine was obtained from a stainless steel tube having an inner diameter of 0.5 mm with the tip at a distance of 3.5 cm from the liquid level. For 21 minutes) by electrospraying. The spray voltage was a value shown in Table 1. Thereafter, it was allowed to cool to room temperature to obtain a solution sample containing indium phosphide.

In order to facilitate comparison of fluorescence characteristics, 0.7 g of zinc stearate, 2.6 mL of dodecanethiol, and 2.4 mL of 1-octadecene as a solvent are added to 1 mL of each solution sample obtained as described above. Heating was performed at 180 ° C. for 20 hours in an autoclave to form an outer shell (shell layer) of zinc sulfide on the surface of indium phosphide. Thereafter, the sample was allowed to cool to room temperature to obtain a solution sample containing indium phosphide having a zinc sulfide outer shell formed on the surface.

(Measurement of fluorescence peak wavelength and half width)
3 mL of hexane was added to the solution sample containing indium phosphide in which the outer shell of zinc sulfide was formed to obtain a dispersion of semiconductor nanoparticles of indium phosphide.

Using a fluorescence spectrophotometer (RF-5300, manufactured by Shimadzu Corporation), the fluorescence spectrum of the resulting dispersion of indium phosphide semiconductor nanoparticles was measured by irradiating with 450 nm light, and the fluorescence peak wavelength and half The price range was determined.
The results are shown in Table 1.

[Comparative Example 1]
After indium phosphide was synthesized by the solvothermal method, an outer shell (shell layer) of zinc sulfide was formed on the surface of the synthesized indium phosphide, and then the fluorescence spectrum was measured.
First, indium chloride, trisdimethylaminophosphine, dodecylamine and toluene are placed in a polytetrafluoroethylene sealed container, blown with nitrogen, sealed, protected with a stainless steel jacket, and heated at 180 ° C. for 24 hours. Indium phosphide was manufactured. Thereafter, in the same manner as in Examples 1 to 5 described above, an outer shell (shell layer) of zinc sulfide was formed on the surface of indium phosphide, and the fluorescence peak wavelength and half width were measured.
The results are shown in Table 1.

As shown in Table 1, the semiconductor nanoparticles produced in Examples 1 to 5 had a shorter fluorescence peak wavelength than the semiconductor nanoparticles produced in Comparative Example 1.
Further, as shown in Table 1, the fluorescence peak wavelength and the half-value width of the fluorescence obtained from the semiconductor nanoparticles produced in Examples 1 to 5 vary depending on the spray voltage.
For example, when the fluorescence spectrum was measured for semiconductor nanoparticles produced with a spray voltage of 2.0 kV to 6.0 kV, fluorescence of 525 ± 20 nm was obtained.
On the other hand, the half-value width was expanded by making the spray voltage smaller.
From the above, the spray voltage is preferably set to 2.0 kV to less than 8.0 kV from the viewpoint of obtaining 525 ± 20 nm fluorescence, while the spray voltage is set to exceed 4.0 kV from the viewpoint of reducing the half width. Presumed to be preferable.

[Example 6]
Using the manufacturing apparatus of the first embodiment described above, cadmium selenide was synthesized and the fluorescence spectrum was measured.

This example was performed as follows. First, 120 mg of cadmium oxide was weighed into a glass eggplant-shaped flask, 2.5 mL of oleic acid was added, and the mixture was heated at 180 ° C. while circulating argon gas to dissolve cadmium oxide in oleic acid. After cooling the solution in which cadmium oxide was dissolved, 1 mL of trioctylphosphine was added to the solution and stirred for 1 hour, and then 1 mL of hexane was further added and stirred. The obtained cadmium solution was filled into a polypropylene syringe, and the syringe was connected to a spray tube of a glass capillary (inner diameter 0.1 mm) whose outer periphery was gold-plated. On the other hand, 120 mg of selenium powder and 15 mL of trioctylphosphine are placed in a glass three-necked flask and heated to 180 ° C. in an oil bath while nitrogen gas is circulated at 20 mL / min in the three-necked flask to dissolve selenium in trioctylphosphine. It was.

Next, using a high voltage generator, the spray tube was adjusted to +8 kV, and the counter electrode previously made of a stainless steel mesh having a diameter of 3 cm previously installed at the bottom of the three-neck flask was adjusted to 0 kV, thereby generating a potential difference of 8 kV. The cadmium solution in the syringe was extruded from the spray tube at a rate of 0.02 mL / min using a syringe pump, and sprayed toward the selenium solution as an electrospray. During this time, nitrogen gas was passed through the three-necked flask at 20 mL / min, and the selenium solution was stirred with a magnetic stirrer. After spraying 0.6 mL of cadmium solution as fine droplets in 30 minutes, the three-necked flask was allowed to cool to room temperature to obtain a colloidal solution containing cadmium selenide.

After adding 5 mL of toluene to 5 mL of the above colloidal solution, 5 mL of methanol was added and stirred well. Since impurities became a precipitate, this was removed with a centrifuge (3000 rpm), and 3 mL of methanol was further added to the remaining supernatant to precipitate cadmium selenide, and the precipitate was collected with a centrifuge. Hexane 3mL was added to this precipitation, and the dispersion liquid of the semiconductor nanoparticle of cadmium selenide was obtained.

A fluorescence spectrophotometer (RF-5300 manufactured by Shimadzu Corporation) was used to irradiate 350 nm light, and the fluorescence spectrum of the obtained dispersion of cadmium selenide semiconductor nanoparticles was measured. As a result, as shown in FIG. 4, light emission with a fluorescence peak wavelength of 425 nm and a half-value width of 80 nm was confirmed.

In Example 6, it was confirmed that fine droplets were sprayed with the cadmium solution when the potential difference between the spray tube and the counter electrode was adjusted between 4 kV and 10 kV.
In addition, when the potential difference between the spray tube and the counter electrode is 8 kV, when the speed at which the liquid is pushed out from the spray tube is changed in the range of 0.005 mL / min to 0.1 mL / mL, It was confirmed that the droplets were sprayed.
Furthermore, the diameter of the microdroplet varies depending on the potential difference and distance between the spray port and the counter electrode, the inner and outer diameters of the spray port, the dielectric constant of the liquid to be sprayed, the viscosity and the ionic strength, etc. It is estimated that the temperature can be adjusted by an inert gas or the like.

[Examples 7 to 9]
Using the manufacturing apparatus of the first embodiment described above, cadmium selenide was synthesized and the fluorescence spectrum was measured.

This example was performed as follows. First, 100 mg of selenium powder and 4 mL of trioctylphosphine were placed in a two-necked flask, and the selenium was dissolved in trioctylphosphine by heating to 120 ° C. in an oil bath while flowing nitrogen gas at 20 mL / min in the two-necked flask. . The obtained selenium solution was filled into a polypropylene syringe, and the syringe was connected to a spray tube of a stainless steel nozzle (inner diameter 0.6 mm). Next, 100 mg of cadmium oxide is weighed into a glass three-necked flask, 11 mL of liquid paraffin and 4 g of stearic acid are added, heated at 180 ° C. while circulating nitrogen gas, and cadmium oxide is dissolved in liquid paraffin to prepare a cadmium solution. Obtained. The cadmium solution was cooled to 160 ° C.

Next, using a high-voltage generator, the spray tube was adjusted to +7 kV, and the counter electrode prepared in advance with a stainless steel mesh having a diameter of 3 cm previously installed at the bottom of the three-neck flask was adjusted to 0 kV to generate a potential difference of 7 kV. The selenium solution in the syringe was extruded from the spray tube at a rate of 0.05 mL / min using a syringe pump, and sprayed toward the cadmium solution as an electrospray. During this time, nitrogen gas was passed through the three-necked flask at 20 mL / min, and the cadmium solution was stirred with a magnetic stirrer. In 40 minutes, 2.0 mL of selenium solution was sprayed as fine droplets. The temperature of the cadmium solution (mixed solution of cadmium and selenium) is maintained at 160 ° C. even after the spraying is finished. In Examples 7 and 8, a part of the solution is made of polypropylene at 10 minutes and 60 minutes after the spraying, respectively. Were collected using a syringe and allowed to cool to room temperature to obtain a colloidal solution containing cadmium selenide. In Example 9, 60 minutes after the end of spraying, the mixed solution of cadmium and selenium was heated from 160 ° C. to 180 ° C. and held at 180 ° C. for 60 minutes to obtain a colloidal solution in the same manner.

3 mL of hexane was added to 0.1 mL of the colloidal solutions of Examples 7 to 9 described above and stirred, and then the supernatant was collected to obtain cadmium selenide semiconductor nanoparticle dispersions.

Using a fluorescence spectrophotometer (RF-5300, manufactured by Shimadzu Corporation), 450 nm light was irradiated, and the fluorescence spectrum of the obtained dispersion of cadmium selenide semiconductor nanoparticles was measured. The results are shown in Table 2 and FIG. In FIG. 5, (1) represents Example 7, (2) represents Example 8, and (3) represents Example 9.

In Examples 7 to 9, it was confirmed that the fluorescence peak wavelength was changed to the longer wavelength side by increasing the temperature held after spraying the fine droplets of the selenium solution or increasing the holding time. .

[Comparative Examples 2 and 3]
Cadmium selenide was synthesized by a hot injection method using the same combination of solutions as in Examples 7 to 9, and the fluorescence spectrum was measured.
First, 100 mg of selenium powder and 4 mL of trioctylphosphine were placed in a two-necked flask, and the selenium was dissolved in trioctylphosphine by heating to 120 ° C. in an oil bath while flowing nitrogen gas at 20 mL / min in the two-necked flask. . The obtained selenium solution was filled into a polypropylene syringe, and the syringe was connected to a stainless steel nozzle (inner diameter 0.6 mm). Next, 100 mg of cadmium oxide is weighed into a glass three-necked flask, 11 mL of liquid paraffin and 4 g of stearic acid are added, heated at 180 ° C. while circulating nitrogen gas, and cadmium oxide is dissolved in liquid paraffin to prepare a cadmium solution. Obtained. The cadmium solution was cooled to 160 ° C.

Next, 2 mL of the selenium solution in the syringe was injected into the cadmium solution from a stainless steel nozzle in 1 second. During this time, nitrogen gas was passed through the three-necked flask at 20 mL / min, and the cadmium solution was stirred with a magnetic stirrer. After the injection, the temperature of the cadmium solution (mixed solution of cadmium and selenium) is maintained at 160 ° C., and after 10 minutes (Comparative Example 2) and 60 minutes (Comparative Example 3), a part of the solution is made of polypropylene. Were collected using a syringe and allowed to cool to room temperature to obtain a colloidal solution containing cadmium selenide.

[Comparative Examples 4 and 5]
A selenium solution and a cadmium solution were prepared in the same manner as in Comparative Examples 2 and 3, and 1 mL of the selenium solution was injected into the cadmium solution maintained at 180 ° C. 10 minutes after the injection (Comparative Example 4), 60 minutes later (Comparative Example 5) A portion of the solution was collected using a polypropylene syringe and allowed to cool to room temperature to obtain a colloidal solution containing cadmium selenide.

The obtained cadmium selenide of Comparative Examples 2 to 5 was measured for fluorescence peak wavelength and half width in the same manner as in Examples 7 to 9 described above. The results are shown in FIGS. 6 and 7 and Table 2. In FIG. 6, (1) represents Comparative Example 2, and (2) represents Comparative Example 3. In FIG. 7, (1) represents Comparative Example 4, and (2) represents Comparative Example 5.
In Example 9, the cadmium and selenium mixed solution was held at 160 ° C. for 60 minutes, then heated to 180 ° C. and further held for 60 minutes.

In particular, the half width of the fluorescence peak of cadmium selenide obtained in Examples 7 to 9 showed a small value compared to the half width of Comparative Examples 2 to 5 obtained at similar holding temperatures and holding times. . In this example, it was confirmed that cadmium selenide capable of obtaining higher-definition light emission can be synthesized as compared with the conventional hot injection method. In Comparative Examples 2 and 3, cadmium selenide obtained by the hot injection method at a holding temperature of 160 ° C. did not show a fluorescent peak with good symmetry, but in Examples 7 and 8, it was obtained at a holding temperature of 160 ° C. The obtained cadmium selenide showed a fluorescent peak with good symmetry. This result shows that cadmium selenide nanoparticles having a uniform particle size can be obtained even at 160 ° C., which is a low temperature in the synthesis of semiconductor nanoparticles.

The disclosure of Japanese Patent Application No. 2017-11118 filed on Jan. 25, 2017 is incorporated herein by reference in its entirety.
All documents, patent applications, and technical standards mentioned in this specification are to the same extent as if each individual document, patent application, and technical standard were specifically and individually stated to be incorporated by reference, Incorporated herein by reference.

DESCRIPTION OF SYMBOLS 1 Nozzle 1a Spray port 2 Supply source 3 Supply pipe 4 Counter electrode 5 Power supply 6, 36 Reactor 7 Cooling pipe 8 Thermal fluid 9 Intermediate electrode 10 Valve 11 Stirrer 12 Magnetic stirrer 13 Vacuum pump L1 Micro droplet L2 Liquid 21 Inactive Gas supply pipe 31 Supply pipe 32 Supply source 33 Distribution pipe 34 Shell formation reactor 100, 200, 300 Semiconductor nanoparticle production apparatus

Claims (15)

A spray unit that sprays one of the liquid (1) containing at least one of the group 12 element and the group 13 element or the liquid (2) containing at least one of the group 15 element and the group 16 element;
Of the liquid (1) and the liquid (2), the other liquid not sprayed is supplied, and the droplet sprayed by the spraying unit comes into contact with the other liquid, and the liquid (1) and the liquid A reactor in which liquid (2) is mixed to react at least one of group 12 elements and group 13 elements contained in liquid (1) with at least one of group 15 elements and group 16 elements contained in liquid (2) When,
A semiconductor nanoparticle manufacturing apparatus comprising: A spray section for spraying a liquid (3) containing at least one of group 12 element and group 13 element and at least one of group 15 element and group 16 element;
The liquid (4) is supplied, and the droplet sprayed by the spray unit comes into contact with the liquid (4), and the liquid (3) and the liquid (4) are mixed and included in the liquid (3). A reactor for reacting at least one of group 12 element and group 13 element and at least one of group 15 element and group 16 element;
A semiconductor nanoparticle manufacturing apparatus comprising: The semiconductor nanoparticle manufacturing apparatus according to claim 1 or 2, wherein the spraying is performed by electrospray. Constituting at least a part of the spray part, or a first electrode attached to at least a part of the spray part;
A second electrode disposed at a position in contact with the liquid when the liquid is supplied to the reactor;
A potential difference forming part that forms a potential difference between the first electrode and the second electrode;
The semiconductor nanoparticle manufacturing apparatus according to claim 3, further comprising: The semiconductor nanoparticle manufacturing apparatus according to claim 4, wherein the second electrode is a ring-shaped, cylindrical, mesh-shaped, rod-shaped, spherical, hemispherical, or plate-shaped conductor. 6. The semiconductor nanoparticle manufacturing apparatus according to claim 4, wherein the potential difference forming unit forms a potential difference of 0.3 kV to 30 kV in absolute value. The semiconductor nanoparticle manufacturing apparatus according to any one of claims 1 to 6, wherein a diameter of a droplet sprayed from the spraying unit is 0.1 袖 m to 100 袖 m. The semiconductor nanoparticle manufacturing apparatus according to any one of claims 1 to 7, wherein an inner diameter of the spray portion is 0.01 mm to 1 mm. The semiconductor nanoparticle production according to any one of claims 1 to 8, wherein a liquid feeding speed of the liquid sprayed from the spraying part is 0.001 mL / min to 1 mL / min per spraying part. apparatus. The semiconductor nanoparticle production apparatus according to any one of claims 1 to 9, further comprising a heating unit that heats the reactor. The semiconductor nanoparticle manufacturing apparatus according to claim 10, wherein the heating unit is a thermal fluid, a solid heat medium, or a heating wire. The semiconductor nanoparticle production apparatus according to any one of claims 1 to 11, further comprising an inert gas supply unit configured to supply an inert gas into the reactor. A material supply unit that supplies the reactor with the core particles produced in the reactor and a material that forms a layer covering at least a part of the surface of the core particles;
The semiconductor nanoparticle production apparatus according to any one of claims 1 to 12, wherein a layer covering at least a part of the surface of the core particle is formed in the reactor. A core particle produced in the reactor and a material that forms a layer covering at least a part of the surface of the core particle are supplied, and further includes a former that forms a layer covering at least a part of the surface of the core particle. The semiconductor nanoparticle production apparatus according to any one of claims 1 to 12. A semiconductor nanoparticle production method for producing semiconductor nanoparticles using the semiconductor nanoparticle production apparatus according to any one of claims 1 to 14.

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