Apparatus for manufacturing nanoparticles of metal oxide and control method therefor

Abstract

According to the present application, an apparatus for manufacturing metal oxide nanoparticles is disclosed, the apparatus comprising: a metal receiving unit; a metal vapor transfer unit which is connected to the metal receiving unit, has a first end and a second end, and extends between the first end and the second end; a first inlet located in the metal vapor transfer unit; a second inlet; and a heater which generates heat, wherein in the metal vapor transfer unit, a ratio of an area of a second vertical cross-section at the second end perpendicular to the longitudinal direction ranging from the first end to the second end to an area of a first vertical cross-section at the first end perpendicular to the longitudinal direction is 0.7 to 1.3, and the area of the first vertical cross-section of the metal vapor transfer unit is equal to or larger than a vertical cross-section of the metal receiving unit with respect to the longitudinal direction.

Description

Device for manufacturing nanoparticles of metal oxide and method for controlling the same

[0001] The present application relates to a device for manufacturing nanoparticles of metal oxide and a method for controlling the same.

[0002] More specifically, the present application relates to a device for producing nanoparticles of metal oxide having a uniform particle size distribution and a method for controlling the same.

[0003] Metal oxide nanoparticles have different physical properties, including optical properties, mechanical properties, and electrical properties, compared to metal oxides with a size of several micrometers or more.

[0004] These properties of nanoparticles are a major driving force behind the diverse research on nanoparticles of materials, and the unpredictable physical properties that can be derived from nanoparticles raise expectations that they will be able to satisfy numerous industrial needs that have yet to be met. To meet these industrial demands, research on various nanoparticles is ongoing. This research not only examines the physical properties of nanoparticles, but also explores methods for more efficient manufacturing of nanoparticles, enabling their already well-discovered physical properties to be widely applied across diverse industrial fields.

[0005] In particular, research on methods for manufacturing nanoparticles is being conducted not only to manufacture nanoparticles more efficiently, but also to manufacture the particle size distribution of nanoparticles more uniformly, which has a significant impact on the physical properties of nanoparticles.

[0006] Among the various nanoparticles, various methods are being studied for manufacturing metal oxide nanoparticles, including the liquid-phase method using liquid precursors and the vapor-phase method using pure metals or precursors. However, the liquid-phase method has the disadvantage of generating waste, while the vapor-phase method has the disadvantage of difficulty in precisely controlling particle size and size distribution.

[0007] The present application relates to a device for manufacturing nanoparticles of metal oxide and a method for controlling the same.

[0008] More specifically, the present application relates to a device for producing nanoparticles of metal oxide having a uniform particle size distribution and a method for controlling the same.

[0009] According to one aspect of the present application, a device for producing nanoparticles of a metal oxide is disclosed. The device for producing nanoparticles of a metal oxide comprises: a metal receiving portion; a metal vapor transfer portion connected to the metal receiving portion, the metal vapor transfer portion having a first end and a second end, and extending between the first end and the second end, wherein the metal receiving portion is connected closer to the first end than to the second end; a first inlet located within the metal vapor transfer portion, wherein the first inlet is located closer to the first end than to the second end; a second inlet, wherein the second inlet is located near the second end; and a heater for generating thermal energy. , wherein the metal vapor transporting section has a ratio of an area of ​​a second vertical cross-section at the second end perpendicular to the longitudinal direction to an area of ​​a first vertical cross-section at the first end perpendicular to the longitudinal direction from the first end to the second end of 0.7 or more and 1.3 or less, and the area of ​​the first vertical cross-section of the metal vapor transporting section is equal to or greater than a vertical cross-section of the metal receiving section with respect to the longitudinal direction.

[0010] According to another aspect of the present application, a method for producing metal oxide nanoparticles is disclosed. The method for producing metal oxide nanoparticles comprises a device comprising: a metal vapor conveying unit having a first end and a second end, the metal vapor conveying unit extending between the first end and the second end; a metal receiving unit located on the first end side of the metal vapor conveying unit and connected to the metal vapor conveying unit; a first inlet provided near the first end within the metal vapor conveying unit; a second inlet provided near the second end; and a heater for generating thermal energy, the device comprising: a first step of providing metal to the metal receiving unit; a second step of providing thermal energy to the metal receiving unit so that the metal can be melted; a third step of providing thermal energy to the metal receiving unit so that the molten metal received in the metal receiving unit can be vaporized; A fourth process of providing an inert gas at a predetermined flow rate toward the metal receiving portion through the first inlet, wherein a first mixed gas of metal vapor of the metal and the inert gas can be generated, and the first mixed gas can be transported toward the second stage, and the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap; and a fifth process of providing a second mixed gas containing oxygen at a predetermined flow rate through the second inlet, wherein the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap, and the metal vapor in the first mixed gas and the oxygen in the second mixed gas react in an oxidation reaction region formed near the second stage to generate a metal oxide.

[0011] According to the device disclosed by the present application, it is possible to manufacture nanoparticles of metal oxide.

[0012] According to the device disclosed by the present application, it is possible to manufacture nanoparticles of metal oxide having a uniform particle size distribution.

[0013] FIG. 1 is a schematic drawing of an apparatus for manufacturing nanoparticles of metal oxide disclosed by the present application.

[0014] Figure 2 is a flow chart illustrating a method for manufacturing nanoparticles of metal oxide disclosed by the present application.

[0015] FIG. 3 is a schematic diagram illustrating an apparatus for manufacturing nanoparticles of metal oxide according to one embodiment of the present application.

[0016] FIGS. 4 to 9 are drawings for explaining the production of metal oxide nanoparticles using a metal oxide nanoparticle production device according to the first embodiment disclosed by the present application.

[0017] FIG. 10 is a schematic diagram illustrating an apparatus for manufacturing nanoparticles of metal oxide according to another embodiment of the present application.

[0018] Figure 11 shows the analysis results of zinc oxide nanoparticles manufactured by the device disclosed by the present application.

[0019] Figure 12 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #1.

[0020] Figure 13 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #2.

[0021] Figure 14 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #3.

[0022] Figure 15 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #4.

[0023] Figure 16 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #5.

[0024] Figure 17 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #6.

[0025] Figure 18 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #7.

[0026] Figure 19 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #8.

[0027] Figure 20 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #9.

[0028] The embodiments described in this application are intended to clearly explain the idea of ​​this application to a person having ordinary skill in the technical field to which this application belongs, and therefore are not limited to the embodiments described in this application, and the scope of this application should be interpreted to include modified or altered examples that do not depart from the idea of ​​this application.

[0029] The terms used in this application have been selected from widely used, common terms, taking into account the functions of this application into account. However, these terms may vary depending on the intentions of those skilled in the art, customs, or the emergence of new technologies in the technical field to which this application pertains. However, if a specific term is defined arbitrarily and used, the meaning of that term will be described separately. Therefore, the terms used in this application should be interpreted based on their substantive meaning and the overall content of this application, rather than simply their names.

[0030] The drawings of this application are intended to facilitate explanation of this application, and the shapes depicted in the drawings may be exaggerated as necessary to help understand this application, so this application is not limited by the drawings.

[0031] If a detailed description of the structure or function of a public notice related to this application is deemed to obscure the gist of this application, a detailed description thereof will be omitted as necessary. Furthermore, the numbers (e.g., "First," "Second," etc.) used throughout the description of this application are merely identifiers used to distinguish one component from another.

[0032]

[0033] In order to solve the above-mentioned conventional problems, according to the present application, a device and a method for producing nanoparticles of metal oxide are disclosed.

[0034] According to one aspect of the present application, a device for producing nanoparticles of a metal oxide is disclosed. The device for producing nanoparticles of a metal oxide comprises: a metal receiving portion; a metal vapor transfer portion connected to the metal receiving portion, the metal vapor transfer portion having a first end and a second end, and extending between the first end and the second end, wherein the metal receiving portion is connected closer to the first end than to the second end; a first inlet located within the metal vapor transfer portion, wherein the first inlet is located closer to the first end than to the second end; a second inlet, wherein the second inlet is located near the second end; and a heater for generating thermal energy. , wherein the metal vapor transporting section has a ratio of an area of ​​a second vertical cross-section at the second end perpendicular to the longitudinal direction to an area of ​​a first vertical cross-section at the first end perpendicular to the longitudinal direction from the first end to the second end of 0.7 or more and 1.3 or less, and the area of ​​the first vertical cross-section of the metal vapor transporting section is equal to or greater than a vertical cross-section of the metal receiving section with respect to the longitudinal direction.

[0035] In some embodiments, the heater may be thermally connected to at least one of the metal receiving portion and the metal vapor transport portion.

[0036] In some embodiments, the first inlet may be fluidly connected to an external inert gas storage tank.

[0037] In some embodiments, the second inlet may be fluidly connected to an external oxygen storage tank.

[0038] In some embodiments, the device for manufacturing metal oxide nanoparticles may further include a first flow controller for controlling the flow rate of inert gas flowing from the inert gas storage tank to the first inlet; and a second flow controller for controlling the flow rate of oxygen flowing from the oxygen storage tank to the second inlet. Furthermore, the device for manufacturing metal oxide nanoparticles may further include a control device for controlling the heater, the first flow controller, and the second flow controller.

[0039] According to another aspect of the present application, a method for producing metal oxide nanoparticles is disclosed. The method for producing metal oxide nanoparticles comprises a device comprising: a metal vapor conveying unit having a first end and a second end, the metal vapor conveying unit extending between the first end and the second end; a metal receiving unit located on the first end side of the metal vapor conveying unit and connected to the metal vapor conveying unit; a first inlet provided near the first end within the metal vapor conveying unit; a second inlet provided near the second end; and a heater for generating thermal energy, the device comprising: a first step of providing metal to the metal receiving unit; a second step of providing thermal energy to the metal receiving unit so that the metal can be melted; a third step of providing thermal energy to the metal receiving unit so that the molten metal received in the metal receiving unit can be vaporized; A fourth process of providing an inert gas at a predetermined flow rate toward the metal receiving portion through the first inlet, wherein a first mixed gas of metal vapor of the metal and the inert gas can be generated, and the first mixed gas can be transported toward the second stage, and the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap; and a fifth process of providing a second mixed gas containing oxygen at a predetermined flow rate through the second inlet, wherein the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap, and the metal vapor in the first mixed gas and the oxygen in the second mixed gas react in an oxidation reaction region formed near the second stage to generate a metal oxide.

[0040] In some embodiments, the second process of providing thermal energy to the metal receiving portion to enable the metal to melt may be such that the temperature of the metal receiving portion is maintained at a temperature equal to or higher than the melting point of the metal received in the metal receiving portion.

[0041] At this time, the third process of providing thermal energy to the metal receiving portion so that the molten metal can be vaporized can be maintained so that the temperature of the metal receiving portion is higher than the melting point of the metal received in the metal receiving portion and lower than the boiling point of the metal.

[0042]

[0043] Configuration of a device for manufacturing nanoparticles of metal oxide

[0044] A device for manufacturing nanoparticles of metal oxide disclosed by the present application is described.

[0045] FIG. 1 is a schematic drawing of an apparatus for manufacturing nanoparticles of a metal oxide disclosed in the present application. Hereinafter, the apparatus for manufacturing nanoparticles of a metal oxide will be described with reference to FIG. 1.

[0046] Components of a device for manufacturing nanoparticles of metal oxides

[0047] The device (1) for producing nanoparticles of metal oxide disclosed by the present application includes a metal receiver (10), a heater (20), a metal vapor guide (30), a first inlet (40), a second inlet (50), and a particle collector (60).

[0048] Function of the metal container (10)

[0049] The metal container (10) provides a space for storing metal raw materials and molten metal.

[0050] The metal receiving portion (10) provides heat generated from the heater (20) to the metal raw material. The metal raw material can be melted by the heat provided through the metal receiving portion (10). The molten metal can be vaporized by the heat provided through the metal receiving portion (10). That is, the metal stored in the metal receiving portion (10) can be vaporized by the heat provided through the metal receiving portion (10). Metal vapor can be emitted from the metal receiving portion (10).

[0051] Shape of metal receiving part (10)

[0052] The metal receiving portion (10) has a shape capable of receiving metal and molten metal. For example, the metal receiving portion (10) may have a bottom surface and a side wall surrounding the bottom surface. At this time, the bottom surface may have a shape such as a circle, an ellipse, a polygon, etc. The side wall may have a shape such as a side wall of a cylinder, a side wall of an elliptical cylinder, a side wall of a polyprism, a side wall of a truncated cone, a side wall of a truncated elliptic cone, a side wall of a prism, etc.

[0053] The metal receiving portion (10) may not have a top surface.

[0054] Temperature and material of the metal receiving portion (10)

[0055] The metal receiving portion (10) is thermally connected to the heater (20). Alternatively, the metal receiving portion (10) may be supplied with thermal energy generated by the heater (20). Alternatively, thermal energy induced by the heater (20) may be provided to the metal receiving portion (10).

[0056] The metal receiving portion (10) can be formed of a material having high thermal conductivity to effectively transfer the thermal energy provided from the heater (20) to the metal.

[0057] The metal receiving portion (10) can maintain a temperature corresponding to the melting point of the metal by the heat provided from the heater (20). Accordingly, the metal receiving portion (10) can be formed of a material that is not destroyed at the temperature at which the metal contained therein melts. In other words, the metal receiving portion (10) can be manufactured of a material having a melting point higher than the melting point of the metal.

[0058] The metal receiving portion (10) can maintain a temperature corresponding to the vaporization point of the metal by the heat provided from the heater (20). Accordingly, the metal receiving portion (10) can be formed of a material that is not destroyed at the temperature at which the metal contained therein vaporizes.

[0059] Function of heater (20)

[0060] The heater (20) generates thermal energy.

[0061] Connection relationship between heater (20) and other components

[0062] The heater (20) can be thermally connected to the aforementioned metal receiving portion (10), metal vapor transfer portion (30), first inlet (40), etc. That is, the heater (20) can provide appropriate thermal energy to the metal receiving portion (10), metal vapor transfer portion (30), and first inlet (40) or the first conduit connected to the first inlet (40), as needed. Thermal energy generated by the heater (20) can be supplied to the metal receiving portion (10), metal vapor transfer portion (30), and first inlet (40) or the first conduit connected to the first inlet (40), as needed. Alternatively, thermal energy induced by the heater (20) can be provided to the metal receiving portion (10), metal vapor transfer portion (30), and first inlet (40) or the first conduit connected to the first inlet (40).

[0063] Use of thermal energy generated by heater (20)

[0064] The heater (20) can provide the generated thermal energy to the metal receiving portion (10). According to some embodiments, the heater (20) can generate thermal energy capable of melting the metal provided to the metal receiving portion (10). That is, the heater (20) can generate thermal energy capable of maintaining the temperature of the metal receiving portion (10) at a temperature corresponding to the melting point of the metal provided to the metal receiving portion (10). According to some embodiments, the heater (20) can generate thermal energy capable of vaporizing the molten metal provided to the metal receiving portion (10). That is, the heater (20) can generate thermal energy capable of maintaining the temperature of the metal receiving portion (10) at a temperature corresponding to the boiling point of the melted metal provided to the metal receiving portion (10).

[0065] The heater (20) can provide the generated thermal energy to the metal vapor transport unit (30). At this time, the heater (20) can generate thermal energy required for a reaction in which the vaporized metal reacts with oxygen gas (hereinafter, metal oxidation reaction) to generate a metal oxide. That is, the heater (20) can generate thermal energy that can maintain the temperature of the metal vapor transport unit (30) at a reaction temperature required for the metal oxidation reaction.

[0066] The heater (20) can provide the generated thermal energy to an inert gas provided through the first inlet (40). The inert gas can be heated to have a temperature that can prevent the vapor of the metal from rapidly cooling. For example, the inert gas can be heated to have a temperature of the melting point of the metal or 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99% of the melting point of the metal.

[0067] Implementation example of heater (20)

[0068] The above heater (20) may be a resistance heater, a combustion heater, an induction heater, etc.

[0069] Function of metal vapor transfer unit (30)

[0070] The metal vapor transport unit (30) provides a pathway through which the metal vapor can move from the metal receiving unit (10) to the oxidation reaction region (70). The metal vapor transport unit (30) can receive the metal vapor and transport the metal vapor to the oxidation reaction region (70).

[0071] The metal vapor transport unit (30) provides a space in which the inert gas introduced through the first inlet (40) described below is mixed with the metal vapor. That is, the metal vapor can be mixed with the inert gas within the metal vapor transport unit (30).

[0072] The metal vapor transport unit (30) provides a path through which not only the metal vapor but also the inert gas introduced through the first inlet (40) described below can move to the oxidation reaction region (70). That is, the inert gas introduced through the first inlet (40) can be mixed with the metal vapor within the metal vapor transport unit (30) to generate a metal vapor - inert gas mixed gas (a mixed gas of metal vapor and non-reactive gas), and the metal vapor transport unit (30) can transport the metal vapor and inert gas mixed gas to the oxidation reaction region (70).

[0073] Shape of metal vapor transfer unit (30)

[0074] The metal vapor transport unit (30) has a shape that can provide a path through which the aforementioned metal vapor or a mixture of metal vapor and inert gas can move. For example, the metal vapor transport unit (30) may have a side surface that defines the path. The side surface may have a shape such as a side surface of a cylinder, a side surface of an elliptical cylinder, a side surface of a polyprism, a side surface of a truncated cone, a side surface of a truncated elliptic cone, a side surface of a prism, etc.

[0075] The metal vapor transfer unit (30) has a first end and a second end, and the side surface may extend between the first end and the second end. The first end may be closer to the metal receiving unit (10) and further away from the oxidation reaction region (70) than the second end. That is, the second end may be closer to the oxidation reaction region (70) and further away from the metal receiving unit (10) than the first end.

[0076] In some embodiments, the cross-sectional area of ​​the cross-section of the first end (hereinafter, the first cross-section) of the metal vapor transport unit (30) may be the same as the cross-sectional area of ​​the cross-section of the second end (hereinafter, the second cross-section) of the metal vapor transport unit (30).

[0077] For example, in some embodiments, it is preferable that the rate of change in the cross-sectional area size in the longitudinal direction of the metal vapor transport unit (30) is 0. That is, when assuming an imaginary axis that is parallel to the longitudinal direction of the metal vapor transport unit (30) and connects the first end and the second end, it is preferable that the size of the cross-sectional area perpendicular to the imaginary axis at any point on the imaginary axis is always the same.

[0078] In some other embodiments, the area of ​​the first cross-section of the metal vapor transporting portion (30) may be different from the area of ​​the second cross-section of the metal receiving portion (30). For example, the area of ​​the first cross-section may be larger or smaller than the area of ​​the second cross-section. However, when the areas of the first cross-section and the second cross-section are different from each other, it is preferable that the ratio of the smaller area to the larger area among the areas of the first cross-section and the second cross-section (= smaller area / larger area * 100%) is 70% or more. That is, the ratio of the smaller area to the larger area among the areas of the first cross-section and the second cross-section may be one selected from 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95,96, 97, 98, and 99. The ratio of the second cross-section to the first cross-section may be any one of real numbers greater than or equal to 0.7 and less than or equal to 1.3. For example, the ratio of the second cross-section to the first cross-section is 0.70, 0.71, 0.72, 0.73, 0.74, 0.75, 0.76, 0.77, 0.78, 0.79, 0.80, 0.81, 0.82, 0.83, 0.84, 0.85, 0.86, 0.87, 0.88, 0.89, 0.90, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 1.00, 1.01, 1.02, 1.03, 1.04, 1.05, 1.06, 1.07, It can be any one value selected from among 1.08, 1.09, 1.10, 1.11, 1.12, 1.13, 1.14, 1.15, 1.16, 1.17, 1.18, 1.19, 1.20, 1.21, 1.22, 1.23, 1.24, 1.25, 1.26, 1.27, 1.28, 1.29, and 1.30.

[0079] However, when the areas of the first cross section and the second cross section are different from each other, it is preferable that the change in the cross section of the metal vapor transport unit (30) along the longitudinal direction of the metal vapor transport unit (30) be continuous so that turbulence does not occur when the metal vapor moves from the first end of the metal vapor transport unit (30) to the second end of the metal vapor transport unit (30).

[0080] In some other embodiments, the rate of change (average rate of change, cm) of the cross-sectional area of ​​the metal vapor transport section (30) in the longitudinal direction 2 / cm) can be one of the real numbers greater than or equal to -7.50 and less than or equal to 7.50. For example, the rate of change of the cross-sectional area can be any one value selected from among -7.00, -6.50, -6.00, -5.50, -5.00, -4.50, -4.00, -3.50, -3.00, -2.50, -2.00, -1.50, -1.00, -0.50, 0.00, 0.50, 1.00, 1.50, 2.00, 2.50, 3.00, 3.50, 4.00, 4.50, 5.00, 5.50, 6.00, 6.50, 7.00, and 7.50.

[0081] In some embodiments, the shape of the first cross-section of the metal vapor transport section (30) may be the same as the shape of the second cross-section of the metal vapor transport section (30). The shapes of the first cross-section and the second cross-section may be a circle, an ellipse, or a polygon.

[0082] In some other embodiments, the shape of the first cross-section of the metal vapor transporting portion (30) may be different from the shape of the second cross-section of the metal vapor transporting portion (30). For example, the shape of the first cross-section may be one shape selected from the group consisting of a circle, an ellipse, and a polygon, and in this case, the shape of the second cross-section may be another shape selected from the group consisting of a circle, an ellipse, and a polygon.

[0083] Connection between the metal vapor transport unit (30) and the metal receiving unit (10)

[0084] The metal vapor transport unit (30) is connected to the metal receiving unit (10).

[0085] The metal vapor transfer unit (30) can be connected to the metal receiving unit (10) so that the metal vapor generated from the metal receiving unit (10) can be transferred to the oxidation reaction region (70) through the metal vapor transfer unit (30) without escaping to the outside.

[0086] The first stage of the metal vapor transport unit (30) can be connected to the metal receiving unit (10).

[0087] In some embodiments, the shape of the first cross-section of the metal vapor transport portion (30) may be the same as the shape of the cross-section of the side surface of the metal receiving portion (10).

[0088] In some embodiments, the cross-sectional area of ​​the first cross-section of the metal vapor transport portion (30) may be larger than the cross-sectional area of ​​the side cross-section of the metal receiving portion (10).

[0089] In some embodiments, the cross-sectional area of ​​the second cross-section of the metal vapor transport portion (30) may be equal to the cross-sectional area of ​​the cross-section of the side surface of the metal receiving portion (10).

[0090] Temperature and material of the metal vapor transfer unit (30)

[0091] The metal vapor transport unit (30) is thermally connected to the heater (20). Thermal energy generated by the heater (20) can be supplied to the metal vapor transport unit (30). Alternatively, thermal energy induced by the heater (20) can be provided to the metal vapor transport unit (30).

[0092] The metal vapor transfer unit (30) can be formed of a material having high thermal conductivity to effectively transfer the thermal energy provided from the heater (20) to the metal vapor.

[0093] The metal vapor transfer unit (30) can maintain a temperature corresponding to the melting point of the metal by the heat provided from the heater (20). Accordingly, the metal vapor transfer unit (30) can be formed of a material that is not destroyed at the temperature at which the metal contained therein melts. That is, the metal vapor transfer unit (30) can be manufactured of a material having a melting point higher than the melting point of the metal.

[0094] The metal vapor transport unit (30) can maintain a temperature corresponding to the vaporization point of the metal by the heat provided from the heater (20). Accordingly, the metal vapor transport unit (30) can be formed of a material that is not destroyed at the temperature at which the metal contained therein vaporizes.

[0095] The metal vapor transport unit (30) can maintain a temperature corresponding to the oxidation reaction temperature described above by the heat provided from the heater (20). Accordingly, the metal vapor transport unit (30) can be formed of a material that is not destroyed at a temperature corresponding to the oxidation reaction temperature.

[0096] Function of the first inlet (40)

[0097] The first inlet (40) provides an inert gas to the surface of the molten metal.

[0098] Location of the first inlet (40)

[0099] The first inlet (40) is located between the metal receiving portion (10) and the metal vapor transport portion (30).

[0100] In some embodiments, the first inlet (40) may be formed on a side surface of the metal vapor transport unit (30). For example, at least one opening may be formed on a side surface of the metal vapor transport unit (30), and the at least one opening may function as the first inlet (40). At this time, the first inlet (40) may be arranged close to the first end of the metal vapor transport unit (30). For example, the first inlet (40) may be closer to the first end than to the second end of the metal vapor transport unit (30).

[0101] In some other embodiments, the first inlet (40) may be formed in an area where the metal receiving portion (10) and the metal vapor transfer portion (30) are connected. For example, at least one opening may be formed in an area where the metal receiving portion (10) and the metal vapor transfer portion (30) are connected, and the at least one opening may function as the first inlet (40).

[0102] In some other embodiments, the first inlet (40) may be formed on a side surface of the metal receiving portion (10). For example, at least one opening may be formed on the side surface of the metal receiving portion (10), and the at least one opening may function as the first inlet (40).

[0103] Type of inert gas provided through the first inlet (40)

[0104] The inert gas is preferably selected from among gases that do not react with the metal vapor and oxygen. For example, the inert gas provided through the first inlet (40) may be one or a combination thereof selected from the group consisting of argon, nitrogen, helium, neon, krypton, xenon, radon, and the like.

[0105] Function of inert gas provided through the first inlet (40)

[0106] The inert gas provided through the first inlet (40) can function as a transport gas to allow the metal vapor to move more smoothly to the oxidation reaction region (70) through the metal vapor transport section (30).

[0107] The inert gas provided through the first inlet (40) can perform a function of preventing the metal vapors from coming into contact with each other while being transported to the oxidation reaction region (70).

[0108] The inert gas provided through the first inlet (40) can further reduce the probability that the metal vapors will come into contact with each other while moving to the oxidation reaction region (70).

[0109] The inert gas provided through the first inlet (40) can prevent metal vapors from aggregating with each other while moving to the oxidation reaction region (70).

[0110] The inert gas provided through the first inlet (40) may function to provide an environment in which the metal vapor can remain in a gaseous state while moving to the oxidation reaction region (70). To this end, the inert gas provided through the first inlet (40) may be preheated to a predetermined temperature.

[0111] The inert gas provided through the first inlet (40) can prevent the metal vapors from growing into crystals larger than a predetermined size.

[0112] Flow rate of inert gas provided through the first inlet (40)

[0113] The flow rate of the inert gas provided through the first inlet (40) is controlled according to a predetermined method.

[0114] Although not shown in the drawing, the first inlet (40) may be connected to a storage for storing the inert gas through a first conduit. At this time, one or a combination of a valve, a flow rate controller, and a pump capable of controlling the flow of the inert gas may be provided between the first inlet (40) and the storage for storing the inert gas.

[0115] As will be described later, the flow rate of the inert gas provided through the first inlet (40) is a factor that affects the average size of the nanoparticles of the metal oxide produced.

[0116] Function of the second inlet (50)

[0117] The second inlet (50) provides a mixed gas containing oxygen that reacts with metal vapor.

[0118] Location of the second inlet (50)

[0119] The second inlet (50) is located between the metal vapor transport unit (30) and the particle collector (60).

[0120] In some embodiments, the second inlet (50) may be formed on a side surface of the metal vapor transport unit (30). For example, at least one opening may be formed on a side surface of the metal vapor transport unit (30), and the at least one opening may function as the second inlet (50). At this time, the second inlet (50) may be arranged close to the second end of the metal vapor transport unit (30). For example, the second inlet (50) may be closer to the second end than to the first end of the metal vapor transport unit (30).

[0121] In some other embodiments, the second inlet (50) may be provided separately from the metal vapor transport unit (30). For example, the second inlet (50) may be positioned close to the second end of the metal vapor transport unit (30). In this case, the second inlet (50) may include at least one nozzle.

[0122] Composition of mixed gas containing oxygen provided through the second inlet (50)

[0123] The gas provided through the second inlet (50) is a mixed gas containing oxygen.

[0124] The above oxygen-containing mixed gas may include oxygen and at least one type of gas other than oxygen.

[0125] It is preferable that at least one other gas other than oxygen is selected from among gases that are non-reactive with the metal vapor and the oxygen. For example, the at least one other gas may be one or a combination thereof selected from the group consisting of argon, nitrogen, helium, neon, krypton, xenon, radon, and the like.

[0126] Function of mixed gas containing oxygen provided through the second inlet (50)

[0127] The mixed gas provided through the second inlet (50) performs the function of providing oxygen that can react with metal vapor.

[0128] The metal vapor and inert gas mixture discharged through the second stage of the metal vapor transport unit (30) is mixed with the mixed gas provided through the second inlet (50).

[0129] At this time, a metal oxide is generated through an oxidation reaction between the metal vapor and the oxygen. In this specification, the region where the metal vapor provided by the metal vapor transfer unit (30) and the oxygen provided through the second inlet meet and undergo an oxidation reaction is referred to as an oxidation reaction region (70).

[0130] The mixed gas provided through the second inlet (50) functions to cool the temperature of the generated metal oxide to prevent the growth of the generated metal oxide crystals from continuing.

[0131] For this purpose, in some embodiments, the mixed gas may be provided at a temperature near room temperature. In some other embodiments, the mixed gas may be provided at a temperature sufficiently lower than the oxidation reaction temperature.

[0132] The flow rate of the mixed gas provided through the second inlet (50)

[0133] The flow rate of the mixed gas provided through the second inlet (50) is controlled according to a predetermined method.

[0134] Although not shown in the drawing, the second inlet (50) may be connected to a storage for storing the oxygen gas and a storage for at least one other type of gas other than the oxygen through at least one second conduit. At this time, one or a combination of a valve, a flow rate controller, and a pump capable of controlling the flow of the mixed gas may be installed in the at least one second conduit.

[0135] As will be described later, the flow rate of the mixed gas provided through the second inlet (50) is a factor that affects the average size of the nanoparticles of the metal oxide produced.

[0136] Fraction of oxygen gas in the mixed gas provided through the second inlet (50)

[0137] The fraction of oxygen gas in the mixed gas provided through the second inlet (50) is controlled according to a predetermined method.

[0138] Although not shown in the drawing, the second inlet (50) may be connected to a second conduit, and the second conduit may be connected to a third conduit connecting the second conduit with an oxygen storage and a fourth conduit connecting the second conduit with a storage for storing at least one type of other gas.

[0139] At this time, one or a combination of a valve, a flow rate controller, and a pump capable of controlling the flow of the oxygen gas may be installed in the third conduit, and one or a combination of a valve, a flow rate controller, and a pump capable of controlling the flow of at least one type of other gas may be installed in the fourth conduit.

[0140] By controlling the flow rate of oxygen provided through the third conduit and the flow rate of other gases provided through the fourth conduit, the fraction of oxygen gas in the mixed gas provided through the second inlet (50) can be controlled.

[0141] As will be described later, the fraction of oxygen gas in the mixed gas provided through the second inlet (50) is a factor that affects the average size of nanoparticles of the metal oxide produced.

[0142] Function of particle collector (60)

[0143] The particle collector (60) performs the function of collecting nanoparticles of the generated metal oxide.

[0144] Implementation example of particle collector (60)

[0145] The above particle collector (60) can be implemented as a cyclone dust collector, an electric dust collector, a bag filter, a mesh filter, a sintered filter, etc.

[0146]

[0147] Hereinafter, a method for manufacturing nanoparticles of a metal oxide using the device for manufacturing nanoparticles of the metal oxide described above will be described.

[0148] Method for producing nanoparticles of metal oxide

[0149] Figure 2 is a flow chart illustrating a method for manufacturing nanoparticles of metal oxide disclosed by the present application.

[0150] Referring to FIG. 2, a method for manufacturing nanoparticles of a metal oxide disclosed by the present application may include a step (S100) of providing a metal raw material to a metal receiving portion, a step (S200) of providing thermal energy to the metal receiving portion so that the metal is melted, a step (S300) of providing thermal energy to the metal receiving portion so that the molten metal is vaporized, a step (S400) of providing an inert gas toward the metal receiving portion, a step (S500) of providing a mixed gas containing oxygen toward an oxidation reaction region, and a step (S600) of collecting metal oxide nanoparticles through a particle collector.

[0151] Process for providing metal to a metal receiving portion (S100)

[0152] According to some embodiments of the method for manufacturing nanoparticles of metal oxide disclosed by the present application, metal may be provided to a metal receiving portion (10).

[0153] The metal provided in the above metal receiving portion (10) may be in a solid phase.

[0154] A process (S200) of providing heat energy to a metal receiving portion so that the above metal is melted.

[0155] According to some embodiments of the method for manufacturing nanoparticles of metal oxide disclosed by the present application, thermal energy may be provided to the metal receiving portion (10).

[0156] The thermal energy provided to the metal receiving portion (10) is used to melt the metal provided to the metal receiving portion (10).

[0157] According to some embodiments, the process (S200) of providing thermal energy to the metal receiving portion (10) may include a process of generating thermal energy through the heater (20).

[0158] As described above, since the heater (20) is thermally coupled to the metal receiving portion (10) or the thermal energy induced by the heater (20) is provided to the metal receiving portion (10), the thermal energy generated by the heater (20) can be transferred to the metal receiving portion (10).

[0159] During process S200, the metal receiving portion (10) may be heated to a temperature that allows the metal to reach at least the melting point or a higher temperature.

[0160] Meanwhile, process S200 may be performed after process S100 is performed, but is not limited thereto, and process S100 may be performed after process S200 is performed or while process S200 is performed.

[0161] As a result of process S200, the metal contained in the metal receiving portion (10) is melted.

[0162] A process (S300) of providing thermal energy to a metal receiving portion so that the molten metal is vaporized.

[0163] According to some embodiments of the method for manufacturing nanoparticles of metal oxide disclosed by the present application, thermal energy may be provided to the metal receiving portion (10) so that molten metal contained in the metal receiving portion (10) can be vaporized.

[0164] The thermal energy provided to the metal receiving portion (10) is used for vaporizing the melted metal located in the metal receiving portion (10).

[0165] According to some embodiments, the process (S200) of providing thermal energy to the metal receiving portion (10) may include a process of generating thermal energy through the heater (20).

[0166] As described above, since the heater (20) is thermally coupled to the metal receiving portion (10) or the thermal energy induced by the heater (20) is provided to the metal receiving portion (10), the thermal energy generated by the heater (20) can be transferred to the metal receiving portion (10).

[0167] According to some embodiments, during process S300, the metal receiving portion (10) may be heated to at least a temperature at which the metal can vaporize. For example, the metal receiving portion (10) may be heated to the boiling point of the metal. In another example, the metal receiving portion (10) may be heated to a temperature lower than the boiling point of the metal. In yet another example, the metal receiving portion (10) may be heated to a temperature higher than the boiling point of the metal.

[0168] According to some embodiments, during process S300, the temperature of the metal receiving portion (10) can be maintained at a temperature higher than the melting point of the metal.

[0169] The temperature at which the metal receiving portion (10) is heated by process S300 may affect the vaporization speed of the molten metal. Therefore, the thermal energy generated by the heater (20) and / or the temperature of the metal receiving portion (10) in process S300 may be appropriately controlled to control the vaporization speed of the molten metal.

[0170] During the process SS00, the molten metal contained in the metal receiving portion (10) is vaporized. Accordingly, metal vapor is generated, and the generated metal vapor escapes from the surface of the molten metal.

[0171] Process for providing an inert gas toward the above metal receiving portion (S400)

[0172] According to some embodiments of the method for producing nanoparticles of metal oxide disclosed by the present application, an inert gas may be provided toward the metal receiving portion (10).

[0173] According to some embodiments, the inert gas may be provided through the first inlet (40).

[0174] According to some embodiments, the inert gas may be provided toward the surface of the molten metal located in the metal receiving portion (10). This may form an interface between the molten metal and the inert gas.

[0175] By continuously supplying the inert gas to the surface of the molten metal, the metal vapor that escapes from the molten metal enters between the inert gases, thereby generating a metal vapor-inert gas mixture.

[0176] The above metal vapor-inert gas mixture can be transferred along the metal vapor transfer unit (30) toward the second stage of the metal vapor transfer unit (30).

[0177] The above metal vapor-inert gas mixture can be transported toward the oxidation reaction region (70) along the metal vapor transport section (30).

[0178] According to some embodiments of the method for producing nanoparticles of metal oxide disclosed by the present application, it is preferable that the metal contained in the metal vapor-inert gas mixture gas remains in a gaseous phase.

[0179] The metal vapor-inert gas mixture may contain metal droplets. These metal droplets may be generated through a phase transition of the metal vapors.

[0180] The metal vapor-inert gas mixture may contain metal particles. These metal particles may be generated through a phase transition of the metal vapors. Accordingly, the term "metal vapor-inert gas mixture" may refer not only to a mixture containing metal vapor in which the metal maintains a gaseous phase, but also to a mixture containing liquid metal droplets or solid metal particles.

[0181] According to some embodiments, the process (S400) of providing an inert gas toward the metal receiving portion may include a process of providing thermal energy to the inert gas.

[0182] According to some embodiments, a process of providing thermal energy to the inert gas may be performed first before performing the process of providing the inert gas (S400).

[0183] The process of providing thermal energy to the above inert gas may include a process of generating thermal energy through the heater (20).

[0184] As described above, the heater (20) is thermally coupled with the first inlet (40) or the first conduit connected to the first inlet (40), or the thermal energy induced by the heater (20) is provided to the first inlet (40) or the first conduit connected to the first inlet (40), so that the thermal energy generated by the heater (20) can be transferred to the inert gas through the first inlet (40) or the first conduit connected to the first inlet (40).

[0185] As described above, the inert gas can perform the function of providing an environment in which the metal vapor can maintain a gaseous phase while the metal vapor moves to the oxidation reaction region (70). To this end, the inert gas needs to be heated to a predetermined temperature before being injected toward the metal receiving portion (10) through the first inlet (40). The predetermined temperature is a temperature determined depending on the type of the metal, and is determined as a temperature that can satisfy at least one of the following conditions.

[0186] Condition 1: Temperature at which the metal vapor can maintain a gaseous phase.

[0187] Second condition: Temperature that can prevent the metal vapor from changing into a liquid phase.

[0188] Third condition: Temperature that can prevent the metal vapor from changing into a solid phase.

[0189] Condition 4: A temperature that can prevent the metal vapors from growing into crystals larger than a predetermined size.

[0190] Condition 5: Temperature at which the metal vapor can undergo an oxidation reaction.

[0191]

[0192] According to some embodiments, process S400 may be performed while process S300 is in progress.

[0193] For example, the first period of time during which the above process S300 continues may partially or fully overlap with the second period of time during which the above process S400 continues.

[0194] Specifically, the starting time point of the process S300 may be earlier than the starting time point of the process S400. In this case, the termination time point of the process S300 may be later than the starting time point of the process S400. Alternatively, the starting time point of the process S400 may be earlier than the starting time point of the process S400. In this case, the termination time point of the process S400 may be later than the starting time point of the process S300.

[0195] According to some embodiments, the second period during which process S400 lasts may partially or fully overlap with the third period during which process S200 lasts.

[0196] Specifically, the start time of the above process S300 may be earlier than the end time of the above process S200.

[0197] A process (S500) for providing a mixed gas containing oxygen toward the above oxidation reaction region

[0198] According to some embodiments of the method for manufacturing nanoparticles of metal oxide disclosed by the present application, a mixed gas containing oxygen may be provided toward the oxidation reaction region (70).

[0199] According to some embodiments, the mixed gas containing oxygen may be provided through the second inlet (50).

[0200] According to some embodiments, the provided mixed gas containing the oxygen meets the metal vapor-inert gas mixed gas transported along the metal vapor transport section (30) in the oxidation reaction region (70), whereby the oxygen can come into contact with the metal vapor, and the oxygen and the metal vapor can react to produce a metal oxide.

[0201] The oxidation reaction of the metal that occurs in the above oxidation reaction region (70) is as follows.

[0202] aM + bO2→ cM x O y

[0203] (Here, M represents a metal atom, O represents an oxygen atom, a is c * x, and b is (c * y) / 2)

[0204]

[0205] The mixed gas containing the above oxygen may be provided to the oxidation reaction region (70) at a predetermined temperature. At this time, the predetermined temperature may be a temperature selected within a temperature range of 10 degrees Celsius or more and 200 degrees Celsius or less.

[0206] The mixed gas containing the oxygen may perform a function of cooling the metal oxide generated in the oxidation reaction region (70) to prevent the size of the metal oxide particles from growing unnecessarily. That is, the metal vapor reaches the oxidation reaction region (70) and is converted into a metal oxide through the oxidation reaction described above, and the metal oxide may be cooled by the mixed gas containing the oxygen while passing through the oxidation reaction region (70).

[0207] According to some embodiments, process S500 may be performed while process S300 is in progress.

[0208] For example, the first duration during which the above process S300 continues may partially or fully overlap with the fourth duration during which the above process S500 continues.

[0209] Specifically, the starting time point of the process S300 may be earlier than the starting time point of the process S500. In this case, the termination time point of the process S300 may be later than the starting time point of the process S500. Alternatively, the starting time point of the process S500 may be earlier than the starting time point of the process S500. In this case, the termination time point of the process S500 may be later than the starting time point of the process S300.

[0210] According to some embodiments, the fourth period during which process S500 continues may partially or fully overlap with the second period during which process S400 continues.

[0211] As a result of process S500, metal oxide nanoparticles are produced.

[0212] The metal oxide nanoparticles may include partially oxidized metal particles. For example, the surface of the particles produced through process S500 may be oxidized, but the core of the particles may not be oxidized. Accordingly, the term "metal oxide nanoparticle" used in the present application may refer not only to particles in which both the surface and core are oxidized, but also to particles having an unoxidized core and an oxidized surface.

[0213] Process for collecting metal oxide nanoparticles through a particle collector (S600)

[0214] According to some embodiments of the method for producing nanoparticles of metal oxide disclosed by the present application, the metal oxide nanoparticles can be collected through the particle collector (60).

[0215] According to some embodiments, the process (S600) of collecting metal oxide nanoparticles through the particle collector (60) may include a process of providing thermal energy to the collected metal oxide nanoparticles.

[0216] First embodiment of a device for producing nanoparticles of metal oxide

[0217] Referring to FIG. 3, an embodiment of a device for manufacturing nanoparticles of metal oxide is described.

[0218] FIG. 3 is a schematic diagram illustrating an apparatus for manufacturing nanoparticles of metal oxide according to one embodiment of the present application.

[0219] Referring to FIG. 3, a device (100) according to one embodiment of the present application may include a metal receiving portion (110), a heater (120), a metal vapor transfer portion (130), a first inlet (140), a second inlet (150), a first conduit (160), a second conduit (170), an inert gas storage tank (180), and an oxygen storage tank (190).

[0220] The metal receiving portion (110), heater (120), metal vapor transfer portion (130), first inlet (140), second inlet (150), first conduit (160), second conduit (170), etc. may correspond to the metal receiving portion (10), heater (20), metal vapor transfer portion (30), first inlet (40), second inlet (50), first conduit, and second conduit described above, respectively. Accordingly, redundant descriptions are omitted.

[0221] The above device (100) may include a kind of furnace having an open cylindrical shape with a bottom plate and a side wall.

[0222] A metal receiving portion (10) arranged on the bottom side may be provided inside the crucible, and the inner surface of the side wall of the crucible may function as a metal vapor transport portion (130).

[0223] The heater (120) may be thermally connected to the bottom surface, or thermal energy induced by the heater (120) may be provided to the bottom surface, and thermal energy generated through the heater (120) may be transferred to the metal receiving portion (110) through the bottom surface.

[0224] The first inlet (140) and the second inlet (150) may be provided on the side wall of the crucible.

[0225] The first conduit (160) is fluidly connected to the first inlet (140), and the second conduit (170) is fluidly connected to the second inlet (150).

[0226] The above first inlet (140) may be fluidly connected to the inert gas storage tank (180).

[0227] The second inlet (150) may be fluidly connected to the oxygen storage tank (190). Meanwhile, the second inlet (150) may be connected to the inert gas storage tank (180) in addition to the oxygen storage tank (190).

[0228] Hereinafter, with reference to FIGS. 4 to 9, the manufacturing of metal oxide nanoparticles using a device (100) according to the first embodiment will be described.

[0229] FIGS. 4 to 9 are drawings for explaining the production of metal oxide nanoparticles using a metal oxide nanoparticle production device according to the first embodiment disclosed by the present application.

[0230] First, as shown in Fig. 4, a solid metal is provided to a metal receiving portion (110).

[0231] Next, as illustrated in FIG. 5, the heater (120) is operated to generate thermal energy, and the thermal energy generated by the heater (120) is transferred to the metal receiving portion (110). Accordingly, the metal provided to the metal receiving portion (110) can be gradually melted.

[0232] When the metal contained in the metal receiving portion (110) begins to melt, an inert gas is injected toward the metal receiving portion (100) through the first inlet (140).

[0233] As described above, as thermal energy continues to be supplied to the molten metal, metal vapor begins to vaporize from the molten metal, thereby generating a metal vapor-inert gas mixture. Furthermore, the metal vapor-inert gas mixture is transported along the metal vapor transport section (130).

[0234] At least when the metal vapor-inert gas mixture starts to be generated, as shown in Fig. 7, the mixture gas containing oxygen is injected through the second inlet (150).

[0235] Over time, as illustrated in FIG. 8, when the mixed gas containing oxygen supplied through the second inlet (150) and the metal vapor-inert gas mixed gas transported through the metal vapor transport section (130) meet, the oxygen and the metal meet each other and an oxidation reaction occurs. As a result, an oxidation reaction region (170) is formed near the second inlet (150).

[0236] Accordingly, as shown in Fig. 9, metal oxide particles are generated.

[0237] At this time, since the metal vapor transport unit (130) is not equipped with a separate nozzle, and the cross-sectional area of ​​the metal vapor transport unit (130) in the gas transport direction does not change rapidly or remains constant, the density of the metal vapor transported through the metal vapor transport unit (130) can be maintained uniformly. In addition, accordingly, the oxidation reaction region (170) where the metal vapor and oxygen meet and an oxidation reaction occurs is formed to have a very large volume, so that the size of the particles of the metal oxide formed can be very uniform.

[0238] Meanwhile, as described above, since the temperature of the mixed gas supplied through the second inlet (150) is maintained relatively very low compared to the temperature of the metal vapor or inert gas, the generated metal oxide particles can be rapidly cooled, thereby allowing metal oxide nanoparticles to be generated.

[0239] Next, although not shown separately in the drawing, the generated metal oxide nanoparticles can be collected through a separate particle collector.

[0240] Second embodiment of a device for producing nanoparticles of metal oxide

[0241] Referring to FIG. 10, another embodiment of a device for manufacturing nanoparticles of metal oxide is described.

[0242] FIG. 10 is a schematic diagram illustrating an apparatus for manufacturing nanoparticles of metal oxide according to another embodiment of the present application.

[0243] Referring to FIG. 10, a device (1000) according to one embodiment of the present application may include a metal receiving portion (1110), a heater (1120), a metal vapor transfer portion (1130), a first inlet (1140), a second inlet (1150), a first conduit (1160), a second conduit (1170), an inert gas storage tank (1180), an oxygen storage tank (1190), a first flow controller (1185a), a second flow controller (1195), a third flow controller (1185b), and a control device (1200).

[0244] The metal receiving portion (1110), heater (1120), metal vapor transfer portion (1130), first inlet (1140), second inlet (1150), first conduit (1160), second conduit (1170), etc. may correspond to the metal receiving portion (110), heater (120), metal vapor transfer portion (130), first inlet (140), second inlet (150), first conduit (160), and second conduit (170) described above, respectively. Accordingly, redundant descriptions are omitted.

[0245] The first flow control unit (1185a) may be placed between the inert gas storage tank (1180) and the first inlet (1140).

[0246] The second flow control unit (1195) may be placed between the oxygen storage tank (1190) and the second inlet (1150).

[0247] The third flow control unit (1185b) may be placed between the inert gas storage tank (1180) and the second inlet (1150).

[0248] The above control device (1200) can generate a control signal for controlling the first flow control unit (1185a), the second flow control unit (1195), the third flow control unit (1185b), and the heater (1120), and the operations of the first flow control unit (1185a), the second flow control unit (1195), the third flow control unit (1185b), and the heater (1120) can be controlled according to the control signal.

[0249] For example, according to the control signal of the control device (1200), the amount, speed, on / off timing, etc. of the inert gas provided from the inert gas storage tank (1180) to the first inlet (1140) can be controlled.

[0250] Alternatively, for example, according to a control signal of the control device (1200), the amount, speed, on / off timing, etc. of oxygen provided from the oxygen storage tank (1190) to the second inlet (1150) may be controlled, and further, the amount, speed, on / off timing, etc. of inert gas provided from the inert gas storage tank (1180) to the second inlet (1150) may be controlled. Accordingly, the amount, flow rate, and on / off timing of the mixed gas including oxygen provided through the second inlet (1150) may be controlled, and further, the fraction of oxygen in the mixed gas including oxygen may be controlled.

[0251] Or, for example, the amount of thermal energy generated by the heater (1120) can be controlled on / off according to the control signal of the control device (1200).

[0252]

[0253] Experimental Example (Manufacture of Zinc Oxide)

[0254] (1) Device configuration

[0255] The device used in the experiment was configured as follows.

[0256] A crucible that functions as a metal receiving portion and a metal vapor transport portion was prepared. The crucible was manufactured in a cylindrical shape with an open top, and the inner diameter of the crucible was 65 mm, the outer diameter of the crucible was 75 mm, and its depth was 80 mm.

[0257] An electric heater having a contact surface that can come into contact with the outer surface of the bottom surface and the outer surface of the side wall of the crucible was manufactured.

[0258] A passage for transporting an inert gas was formed on the side wall of the crucible, an opening facing the interior of the crucible was formed on the lower part of the side wall of the crucible, and the passage and the opening were connected to each other. That is, the opening was made to function as the first inlet described above, and the passage was made to function as at least a part of the first conduit.

[0259] A second inlet for oxygen supply was provided on the upper side of the side wall of the crucible.

[0260] An electrostatic precipitator was placed on the upper side of the crucible to collect metal oxides.

[0261] The electrostatic precipitator used was the OCEP-20 product from JK Systems Co., Ltd.

[0262] The first inlet is connected to a storage tank storing an inert gas, and the second inlet is connected to a storage tank storing an inert gas and a storage tank storing a mixed gas containing oxygen.

[0263] (2) Preparation of raw materials

[0264] Zinc metal was used as the metal, and the zinc used had a purity of 99.995%.

[0265] Argon gas was used as an inert gas, and the argon gas used was purchased from World Energy Systems of Korea, and the purity of the argon used was 99.999%.

[0266] The mixed gas containing oxygen was used as a mixed gas containing 21% oxygen, approximately 78% nitrogen, and other remaining gases.

[0267] (3) Experimental Example #1

[0268] First, 10 g of zinc metal was placed inside the crucible, and the crucible was heated to approximately 880 degrees.

[0269] When the zinc was melted (approximately 3 minutes after the crucible began to melt), argon gas (an inert gas) was supplied to the crucible through the first inlet at a flow rate of 10 L / min. The argon gas was preheated to a temperature of approximately 220 degrees and then supplied into the crucible.

[0270] When the zinc was vaporized (or about 5 minutes after the crucible was started to be heated), a mixed gas containing oxygen and argon in a ratio of 0.2:0.98 (oxygen fraction of about 0.4%) was supplied to the crucible at a flow rate of about 10 L / min through the second inlet. That is, the oxygen fraction of the gas supplied through the second inlet was controlled to about 0.4%. At this time, the temperature of the supplied oxygen-argon mixed gas was room temperature.

[0271] (4) Experimental examples #2-#4 (for analysis of results according to zinc heating temperature)

[0272] In Experimental Examples #2 to #4, compared to Experimental Example #1, only the heating temperature of the crucible was changed as shown in [Table 1] below, and the remaining experimental conditions were maintained as is.

[0273] Heating temperature of the crucible (℃)Experimental example #2910Experimental example #3950Experimental example #4990

[0274] (5) Experimental examples #5 - #7 (for analysis of results according to oxygen fraction)

[0275] In Experimental Examples #5 to #7, compared to Experimental Example #1, only the oxygen fraction in the mixed gas supplied through the second inlet was changed as shown in [Table 2] below, and the remaining experimental conditions were maintained as is.

[0276] Experimental Example Mixed Gas / Argon Gas Oxygen Fraction (%) Experimental Example #50.5 / 9.51 Experimental Example #61 / 92 Experimental Example #72 / 84

[0277] (6) Experimental examples #8 and #9 (for analysis of results according to argon flow rate)

[0278] In Experimental Examples #8 and #9, compared to Experimental Example #1, only the flow rate of argon gas supplied through the first inlet was changed as shown in [Table 3] below, and the remaining experimental conditions were maintained as is.

[0279] Experimental Example Argon Flow Rate (L / min) Experimental Example #86 Experimental Example #92

[0280] (8) Analysis results

[0281] Analysis was conducted on zinc oxide manufactured according to Experimental Examples #1 to #9.

[0282] First, we analyzed whether the manufactured particles were indeed zinc oxide. X-ray photoelectron spectroscopy (XPS) was used as the analysis method.

[0283] As a result of the analysis, it was confirmed that the particles manufactured according to Experimental Examples #1 to #9 contained zinc atoms and oxygen atoms, as shown in Fig. 11, and that no other atoms were included. In conclusion, it was confirmed that all nanoparticles manufactured according to the methods of Experimental Examples #1 to #9 were zinc oxide. However, when visually inspected, it was confirmed that some unreacted zinc that did not participate in the oxidation reaction was also included.

[0284]

[0285] (9) Results of comparative experiments

[0286] The size of the zinc oxide nanoparticles manufactured through Experimental Examples #1 to #9 was analyzed. The size analysis of the manufactured zinc oxide nanoparticles was conducted based on photographs taken of the manufactured zinc oxide particles using an SEM.

[0287] Figure 12 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #1.

[0288] Figure 13 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #2.

[0289] Figure 14 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #3.

[0290] Figure 15 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #4.

[0291] Figure 16 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #5.

[0292] Figure 17 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #6.

[0293] Figure 18 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #7.

[0294] Figure 19 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #8.

[0295] Figure 20 is an SEM photograph of zinc oxide particles manufactured by Experimental Example #9.

[0296] Through FIGS. 12 to 20, it was found that by melting the target metal to be manufactured by the method and device disclosed by the present application, and then heating the target metal at a temperature slightly higher than the vaporization point or the vaporization point according to the embodiments disclosed by the present application, while supplying an inert gas to the surface of the molten metal so that the vaporized metal atoms are detached from the surface of the molten metal, and when the detached metal atoms meet a mixed gas containing oxygen in a well-dispersed state in the air, nano-sized metal oxide particles with well-controlled particle sizes can be obtained.

[0297] In particular, through FIGS. 12 to 15, it can be seen that the size of the manufactured zinc oxide particles gradually increases as the heating temperature of the crucible increases.

[0298] Furthermore, through FIG. 12 and FIG. 16 to FIG. 18, it was found that as the oxygen fraction of the mixed gas (i.e., the flow rate of the mixed gas) increases, the size of the manufactured zinc oxide particles gradually increases.

[0299] In addition, through Fig. 12, Fig. 19 and Fig. 20, it was found that as the flow rate of the inert gas supplied to the surface of the molten zinc decreased, the size of the manufactured zinc oxide particles gradually increased.

[0300] In conclusion, it was found that metal oxide nanoparticles can be manufactured using the device disclosed by the present application, and further, the size of the metal oxide nanoparticles can be controlled to various sizes by controlling the temperature for heating the metal (particularly, the temperature of the crucible for vaporizing the metal), the flow rate of an inert gas provided to the surface of the molten metal, and the fraction of oxygen or the flow rate of oxygen provided for oxidizing the vaporized metal in the air.

Claims

1. Metal receiving part; A metal vapor transfer unit connected to the metal receiving portion, having a first end and a second end, and extending between the first end and the second end, wherein the metal receiving portion is connected closer to the first end than to the second end; A first inlet located within the metal vapor transport section, wherein the first inlet is located closer to the first end than to the second end; a second inlet - wherein said second inlet is located near said second stage -; and A heater that generates thermal energy; Includes, The above metal vapor transport unit, The ratio of the area of ​​the second vertical cross-section in the second end perpendicular to the longitudinal direction to the area of ​​the first vertical cross-section in the first end perpendicular to the longitudinal direction from the first end to the second end is 0.7 or more and 1.3 or less, The area of ​​the first vertical cross-section of the metal vapor transporting portion is equal to or greater than the vertical cross-section of the metal receiving portion in the longitudinal direction. A device for manufacturing metal oxide nanoparticles.

2. In paragraph 1, The heater is thermally connected to at least one of the metal receiving portion and the metal vapor transport portion. A device for manufacturing metal oxide nanoparticles.

3. In paragraph 1, The above first inlet is fluidly connected to an external inert gas storage tank. A device for manufacturing metal oxide nanoparticles.

4. In paragraph 1, The above second inlet is fluidly connected to an external oxygen storage tank. A device for manufacturing metal oxide nanoparticles.

5. In paragraph 1, A first flow controller that controls the flow rate of the inert gas flowing from the inert gas storage tank to the first inlet; and Further comprising a second flow controller for controlling the flow rate of oxygen flowing into the second inlet from the oxygen storage tank; A device for manufacturing metal oxide nanoparticles.

6. In paragraph 5, Further comprising a control device for controlling the heater, the first flow controller and the second flow controller; A device for manufacturing metal oxide nanoparticles.

7. A method for manufacturing metal oxide nanoparticles using a device comprising a first stage and a second stage, a metal vapor transporting section extending between the first stage and the second stage; a metal receiving section located on the first stage side of the metal vapor transporting section and connected to the metal vapor transporting section; a first inlet provided near the first stage within the metal vapor transporting section; a second inlet provided near the second stage; and a heater for generating thermal energy. A first process of providing metal to the metal receiving portion; A second process of providing thermal energy to the metal receiving portion so that the metal can be melted; A third process of providing thermal energy to the metal receiving portion so that the molten metal received in the metal receiving portion can be vaporized; A fourth process of providing an inert gas at a predetermined flow rate toward the metal receiving portion through the first inlet, wherein a first mixed gas of the metal vapor of the metal and the inert gas can be generated, and the first mixed gas can be transported toward the second stage, and the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap; and A fifth process of providing a second mixed gas containing oxygen at a predetermined flow rate through the second inlet, wherein the time during which the third process is maintained and the time during which the fourth process is maintained at least partially overlap, and the metal vapor in the first mixed gas and the oxygen in the second mixed gas react in an oxidation reaction region formed near the second stage to generate a metal oxide; Including A method for producing metal oxide nanoparticles.

8. In paragraph 7, The second process of providing thermal energy to the metal receiving portion so that the metal can be melted is to maintain the temperature of the metal receiving portion at a temperature equal to or higher than the melting point of the metal received in the metal receiving portion. A method for producing metal oxide nanoparticles.

9. In paragraph 7, The third process of providing thermal energy to the metal receiving portion so that the molten metal can be vaporized is to maintain the temperature of the metal receiving portion at a temperature higher than the melting point of the metal received in the metal receiving portion and lower than the boiling point of the metal. A method for producing metal oxide nanoparticles.

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