KR102548412B1 - Manufacturing method of graphene nano composite powder - Google Patents

Abstract

The present invention relates to a method for preparing a graphene nanocomposite powder. The manufacturing method of the graphene nanocomposite powder includes charging a metal wire into a mixed solution in which graphene oxide is dispersed; and forming nanopowder containing metal or metal oxide by reacting the metal powder formed by electrically detonating the metal wire by applying energy to the metal wire loaded in the mixed solution and the graphene oxide. The step of forming the nanopowder may include: forming reduced graphene oxide in which reduction and defect healing of the graphene oxide is performed due to the exploding metal wire; and combining the metal or metal oxide-containing nanopowder and the reduced graphene oxide to form a composite structure.

Description

Manufacturing method of graphene nano composite powder {Manufacturing method of graphene nano composite powder}

The present invention relates to a method for producing a graphene nanocomposite powder, and more particularly, to a nanocomposite powder composed of graphene-metal or graphene-metal oxide using electrical explosion and a method for preparing the same.

Recently, new mechanical/physical properties expressed by the volume effect due to the increase in the surface area of metal and the interaction between metal particles are attracting attention by grafting nanotechnology that refines metal (about 100 nm or less). In addition, interest in composite powder materials that can add new functions or improve electrical properties while maintaining properties through the dispersion of inorganic materials in conventional metal powders is growing.

On the other hand, graphene is a layered material composed of a single layer of carbon atoms. Graphene has excellent thermal conductivity, electrical conductivity, large surface area, high chemical stability, and light weight, so it is attracting attention as a reinforcing agent for metal powder as an inorganic material. For this reason, the development of a composite material of graphene and metal powder or graphene and metal oxide is being studied. The prior art provides a metal salt in a solvent in which graphene oxide is dispersed, and reduces it through heat treatment with a reducing agent to prepare a composite powder in which graphene is dispersed between base metal powders. there is. However, when using the conventional method, the process step is also complicated, and there is a problem in that the process cost and time are high.

Publication No. 10-2018-0079496 (2018.07.11)

An object of the present invention is to solve various problems including the above problems, and to provide a method for preparing a graphene nanocomposite powder having excellent mechanical/physical properties. However, these tasks are illustrative, and the scope of the present invention is not limited thereby.

According to one aspect of the present invention for solving the above problems, a method for producing a graphene nanocomposite powder is provided. The manufacturing method of the graphene nanocomposite powder includes charging a metal wire into a mixed solution in which graphene oxide is dispersed; and forming a composite structure by reacting nanopowder containing a metal or metal oxide formed by electrically detonating the metal wire by applying energy to the metal wire loaded in the mixed solution and the graphene oxide. In the step of forming the composite structure, the reduced graphene oxide is formed by reducing the graphene oxide and repairing defects due to the exploding metal wire, so that the nanopowder and the reduced graphene oxide are combined Forming the composite structure; may include.

In the manufacturing method of the graphene nanocomposite powder, the composite structure may have a structure in which the reduced graphene oxide in the form of a thin film is bonded between the nanopowder and the nanopowder surrounds the reduced graphene.

In the method for preparing the graphene nanocomposite powder, the nanopowder may have a size of 100 nm or less (greater than 0).

In the method of manufacturing the graphene nanocomposite powder, the step of forming the nanopowder includes applying a voltage pulse equal to or greater than the energy required for sublimation of the metal wire in consideration of the size of the metal wire loaded in the mixed solution. can include

In the manufacturing method of the graphene nanocomposite powder, the voltage pulse may be a voltage (V) calculated in consideration of the sublimation energy of the metal wire and the capacitor capacity (C) of the device.

In the method for preparing the graphene nanocomposite powder, the mixed solution is mixed using a stirrer after dispersing the graphene oxide in an organic solvent, and may optionally further contain distilled water.

In the method for preparing the graphene nanocomposite powder, the organic solvent is acetone, pyridine, methyl ethyl ketone, methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, ethylene glycol, polyethylene glycol, tetrahydrofuran, Dimethylformamide, dimethylacetamide, N-methyl-2-pyrrolidone, hexane, cyclohexanone, toluene, chloroform, dichlorobenzene, dimethylbenzene, trimethylbenzene, methylnaphthalene, nitromethane, acrylonitrile, octadecylamine , Any one selected from aniline and dimethyl sulfoxide, or a mixture of two or more may be included.

In the manufacturing method of the graphene nanocomposite powder, the oxygen content of the reduced graphene oxide may be 5% or less (more than 0).

In the manufacturing method of the graphene nanocomposite powder, the reduced graphene oxide can cure 95% or more of the pore defects by growing graphene in the region where the pore defects of the graphene oxide exist.

In the manufacturing method of the graphene nanocomposite powder, the diameter of the metal wire may have a diameter of 1 mm or less (greater than 0), and the length of the metal wire may have a length of 10 cm or less (greater than 0).

In the manufacturing method of the graphene nanocomposite powder, the metal wire is manganese (Mn), copper (Cu), chromium (Cr), iron (Fe), nickel (Ni), cobalt (Co), gold (Au) , silver (Ag) and platinum (Pt) may include any one or a mixture of two or more of transition metal elements such as (Ag) and platinum (Pt).

According to one embodiment of the present invention made as described above, it is possible to provide a method for manufacturing a graphene nanocomposite powder capable of reducing process cost and process time compared to a conventional graphene composite powder manufacturing process. Since the graphene nanocomposite powder prepared by the above preparation method contains less than 5% oxygen, an additional reduction process can be omitted. In addition, an improvement in electrical conductivity and an antioxidant effect of the metal nanopowder can be expected by graphene. The scope of the present invention is not limited by these effects.

1 is a process flow chart schematically illustrating a method for manufacturing a graphene nanocomposite powder according to an embodiment of the present invention.
2 is a diagram schematically illustrating the structure of an electric explosion device according to an embodiment of the present invention.
Figure 3 is an experimental example of the present invention, (a) Comparative Example 1 and (b) graphene oxygen content of Example 1 is the result of analyzing the energy dispersive spectroscopy (EDS) of the transmission electron microscope (TEM) .
Figure 4 is an experimental example of the present invention, (a) Comparative Example 1 and (b) Example 1 graphene defect distribution is analyzed by transmission electron microscope (TEM) image.
5 is an experimental example of the present invention, (a) Example 1 and (b) an image of the nanocomposite powder form of Example 4 analyzed with a scanning electron microscope.
6 is an experimental example of the present invention, which is a result of analyzing the nanocomposite powders of Examples 1 to 6 and Comparative Example 1 by Raman spectroscopy.
7 is an experimental example of the present invention, and is a result of analyzing the nanocomposite powders of Example 1, Example 3, Example 4 and Example 6 by X-ray diffraction (XRD) method.
8 is an experimental example of the present invention, and is a result of measuring the conductivity of Examples 1 and 2 by the powder resistance measurement method.
9 is an experimental example of the present invention, and is a result of analyzing electromagnetic wave shielding characteristics of Examples 1 and 4.

Hereinafter, the present invention will be described in more detail with reference to examples and accompanying drawings. These examples are only for explaining the present invention in more detail, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples.

Hereinafter, a method for manufacturing a graphene nanocomposite powder using a single electrical explosion method will be described in detail with reference to the drawings.

1 is a process flow chart schematically illustrating a method for manufacturing a graphene nanocomposite powder according to an embodiment of the present invention.

Referring to FIG. 1, the method of manufacturing a graphene nanocomposite powder (S100) according to an embodiment of the present invention includes the step of charging a metal wire into a mixed solution in which graphene oxide is dispersed (S110), The metal powder formed by applying energy to the metal wire to electrically explode the metal wire and graphene oxide react with each other to form nanopowder containing metal or metal oxide (S120), collecting the nanopowder ( S130) may be included.

Specifically, the step of forming the nanopowder (S120) is the step of forming the reduced graphene oxide in which the graphene oxide is reduced and the defect is healed due to the exploding metal wire, and the nanoparticles including the metal or metal oxide A step of combining the powder and the reduced graphene oxide to form a composite structure may be included.

Here, the graphene oxide (GO) is based on a carbon structure in a sheet form like graphene. It is known that various oxygen functional groups such as hydroxyl groups, epoxy groups, carboxyl groups, and ketone groups are bonded to the upper surface or end of the sheet.

The metal wire is exploded by receiving a voltage pulse higher than the energy required for metal sublimation. At this time, the metal expands while dissipating heat due to high energy, and scatters in the mixed solution to form nanopowders of metal or metal oxide. In this process, in the process of combining the metal or metal oxide nanopowder with the graphene oxide contained in the mixed solution to form a complex, bonds between oxygen functional groups are broken to form reduced graphene oxide. At this time, the physical and electrical properties of graphene are also restored. The graphene nanocomposite powder prepared in this way can be applied to fields such as electromagnetic wave shielding or anode materials and heat dissipation films for supercapacitors.

The graphene nanocomposite powder realized by the manufacturing method of the graphene nanocomposite powder according to an embodiment of the present invention can be provided as an electromagnetic wave shielding sheet, a heat dissipation film, and an electrode or electrode contact of an energy storage device. Since the method applied to these is already known in the art, a detailed description thereof will be omitted.

Meanwhile, the reduced graphene oxide may have an oxygen content of 5% or less (more than 0). In the present invention, the reduced graphene oxide may be one in which 95% or more of the pore defects are healed by growing graphene in a region where the pore defects of the graphene oxide exist.

The composite structure including the nanopowder has a structure in which the reduced graphene oxide in the form of a thin film is bonded between the nanopowder and the nanopowder surrounds the reduced graphene. The nanopowder has a size of 100 nm or less (greater than 0). The nanopowder including the reduced graphene oxide has a relatively better electrical conductivity than the metal nanopowder having the same packing density.

Meanwhile, the graphene oxide may be reduced by supplying energy required for sublimation of the metal material constituting the metal wire to explode the metal wire in an organic solvent in which the graphene oxide is dispersed. Here, the voltage applied to the metal wire is 1 to 5 times larger than the energy for sublimating the metal wire. At this time, the applied pulse voltage is supplied as much as the value calculated by the following relational expression 1.

[Relationship 1]

Considering the size of the metal wire loaded into the mixed solution, the voltage (V) is calculated and applied in consideration of the sublimation energy of the metal wire and the capacitor capacity (C) of the device according to the relational expression 1 above.

The mixed solution is obtained by dispersing graphene oxide powder in an organic solvent. The organic solvent is acetone, pyridine, methyl ethyl ketone, methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, ethylene glycol, polyethylene glycol, tetrahydrofuran, dimethylformamide, dimethylacetamide, N-methyl- Any one selected from 2-pyrrolidone, hexane, cyclohexanone, toluene, chloroform, dichlorobenzene, dimethylbenzene, trimethylbenzene, methylnaphthalene, nitromethane, acrylonitrile, octadecylamine, aniline, dimethylsulfoxide and carbon or a mixture of two or more. In some cases, the degree of reduction of graphene oxide can be controlled by selectively diluting the organic solvent with distilled water.

The metal wire has a diameter of 1 mm or less (greater than 0). The metal wire rod includes, for example, manganese (Mn), copper (Cu), chromium (Cr), iron (Fe), nickel (Ni), cobalt (Co), gold (Au), silver (Ag), and platinum ( It may include any one or a mixture of two or more of transition metal elements such as Pt).

A method of dispersing graphene oxide in the mixed solution is to stir and disperse the graphene oxide powder in the mixed solution using a magnetic stirrer and ultrasonic grinding. Here, the magnetic stirrer and ultrasonic grinding are already known technologies, and detailed descriptions thereof are omitted. Thereafter, the mixed solution in which graphene oxide is dispersed is filled in the chamber 80 of the electric explosion device 100 shown in FIG. 2, and the metal wire 30 is charged.

Referring to FIG. 2, the electric explosion device 100 includes an excess gas outlet 10, a high voltage electrode 20, a metal wire 30, a wire guide 40, a ground electrode 50, and an ultrasonic powder dispersion device 70 ) and a chamber 80, and the mixed solution 60 in which the graphene oxide powder is dispersed in the chamber 80 is filled.

Here, at least all of the high voltage electrode 20 and the ground electrode 50 are supported in the mixed solution 60 in which graphene oxide powder is dispersed, and the metal wire 30 is mixed at a constant speed through the wire guide 40. fed into the solution (60). Thereafter, in the chamber 60 filled with the mixed solution 60, a voltage in the form of a pulse is applied using the high voltage electrode 20 to electrically explode the metal wire 30. At the same time, a step of sublimating the metal wire 30 in liquid to form metal or metal oxide nanopowder and simultaneously reducing graphene oxide powder to form nanopowder (S120) is performed.

The metal wire 30 is automatically and constantly supplied in a length of about 2.4 cm by the electric explosion device 100 to connect the anode and the cathode. At this time, the magnitude of the pulse power applied to the metal wire 30 supplies energy 1 to 5 times larger than the sublimation energy of the loaded metal wire.

In addition, as the pore defects included in the graphene oxide are healed during the reduction process by electric explosion, the density of defects in the reduced graphene oxide is remarkably reduced. In the reduction step, the energy of the carbon source included in the organic solvent and the metal or metal oxide nanopowder exploding at the defect location of the graphene oxide powder reacts, thereby healing the defect inside the graphene oxide during reduction. It is judged to be because Reduced graphene oxide having defects healed exhibits excellent mechanical and chemical properties, including high electrical conductivity, compared to conventional reduced graphene oxide containing a large number of defects therein.

After the step of forming the nanopowder (S120), the step of collecting the nanocomposite powder in which the reduced graphene powder and the metal nanopowder are mixed with each other (S130) may be performed.

As shown in FIG. 5 , the graphene nanocomposite powder has a complex entangled shape, and the nanocomposite powder can be obtained by performing dehydration and drying. The nanocomposite powder can be used as an electrode material or heat dissipation material for energy storage devices such as batteries and supercapacitors, a conductive composite material for electromagnetic wave shielding, and a sensor.

Hereinafter, embodiments for better understanding of the present invention will be described. However, the following examples are only for helping understanding of the present invention, and the present invention is not limited only to the following examples.

<Example 1_Manufacture of graphene/copper nanocomposite powder>

20 ml of a commercially available graphene oxide (GO-V50) dispersion was mixed with 800 ml of ethanol, and stirred for 30 minutes with an ultrasonic cleaner and a magnetic stirrer to prepare a mixed solution. The prepared aqueous solution was filled in the chamber 80 of the electric explosion device 100 shown in FIG. 2, and a copper (Cu) wire having a diameter of 200 μm was connected to the device. The connected copper wire is automatically supplied constantly by a length of 2.4 cm. Then, by the two connected electrodes (anode and cathode), when the copper wire converts the voltage of 1456V into energy, an energy pulse of about 180J is supplied, and energy four times greater than the sublimation energy per unit volume is instantly supplied, causing an explosion.

The instantaneously heated and expanded copper wire is dispersed in the form of nanopowder in the liquid phase, and meets with graphene oxide to induce a reduction reaction and a defect healing reaction. At this time, the electrical explosion was repeated a thousand times to prepare a graphene/copper nanocomposite powder. Here, when preparing the nanocomposite powder, the amount of nanopowder produced by one electrical explosion is determined by the length of the loaded metal wire, and the electrical explosion is repeatedly performed to prepare the nanopowder.

The copper/reduced graphene composite nanopowder dispersed in the mixed solution was separated from the mixed solution using a centrifuge, washed with distilled water, washed with a centrifuge, and then dried through freeze-drying. powder was prepared.

<Example 2_Manufacture of carbon-coated copper nanopowder>

Ethanol was charged into the electric explosion device (see FIG. 2) without using graphene oxide in the mixed solution. Thereafter, the connected copper wire was continuously and automatically supplied by a length of 2.4 cm, and an electric explosion was performed thousands of times with energy of 1456V (180J) to prepare carbon-coated copper nanopowder.

<Example 3_Manufacture of copper and copper oxide nanopowder>

Distilled water was charged into the electric explosion device (see FIG. 2) without using graphene oxide and ethanol. Thereafter, the connected copper wire was continuously and automatically supplied by a length of 2.4 cm, and an electric explosion was performed thousands of times with energy of 1456V (180J) to prepare pure copper nanopowder.

<Example 4_Preparation of graphene/nickel nanocomposite powder>

After preparing the same mixed solution as in Experimental Example 1, it was charged in the chamber of an electric explosion device (see FIG. 2), and a nickel (Ni) wire having a diameter of 200 μm was connected to the device. An electric explosion was performed with an energy of 1415 V (170 J) to prepare a nickel/reduced graphene composite nanopowder. Except for the conditions mentioned above, the rest of the experimental variables were carried out in the same manner as in Experimental Example 1.

<Example 5_Manufacture of carbon-coated nickel nanopowder>

In the same manner as in Example 2, ethanol was charged into an electric explosion device (see FIG. 2). After changing to a nickel wire instead of a copper wire, an electric explosion was performed with an energy of 1415V (170J) to prepare carbon-coated nickel nanopowder. Except for the conditions mentioned above, the rest of the experimental parameters were carried out in the same manner as in Experimental Example 2.

<Example 6_Manufacture of nickel and nickel oxide nanopowder>

In the same manner as in Example 3, distilled water was charged into an electric explosion device (see FIG. 2). After changing to a nickel wire instead of a copper wire, an electric explosion was performed with an energy of 1415V (170J) to prepare pure nickel nanopowder. Except for the conditions mentioned above, the rest of the experimental parameters were carried out in the same manner as in Experimental Example 3.

<Comparative Example 1_Oxidized Graphene>

Commercially available graphene oxide (GO-V50) was dispersed in distilled water to prepare a graphene oxide dispersion solution having a concentration of 0.5 mg/ml. By performing energy dispersive spectrometry (EDS) of a transmission electron microscope (TEM), the oxygen content of graphene oxide is shown in FIG. 3 and the defect distribution of graphene oxide is shown in FIG. 4 through microstructure images.

<Evaluation of reduced graphene oxide>

Table 1 below summarizes the oxygen content at each position for each sample shown in FIG. 3 in a table. Hereinafter, GO is graphene oxide and rGO is reduced graphene oxide.

Comparative Example 1 GO (%) Experimental Example 1
rGO (%) O ₁ 11.15 0.62 O ₂ 11.25 0.28 O ₃ 10.09 0.32

Referring to FIG. 3 and Table 1, in the analysis results of the graphene oxide of the sample of Comparative Example 1, the oxygen ratio was measured to be 11.15% in the O ₁ region, 11.25% in the O ₂ region, and 10.09% in the O ₃ region. The reduced graphene of Experimental Example 1 showed an oxygen content of 0.62% in the O ₁ region, 0.28% in the O ₂ region, and 0.32% in the O ₃ region, confirming that the oxygen content dropped to 1% or less through electrical explosion. could

Through the above results, it was confirmed that the electric explosion process is effective in reducing graphene oxide. This is determined to be that when the copper wire is momentarily energized, sublimated, and exploded, being dispersed in the liquid phase in the form of a powder of several tens of nanometers, it reacts with graphene oxide in the liquid phase with high thermal energy and oxygen is separated.

Referring to FIG. 4, it was confirmed that the graphene oxide of the sample of Comparative Example 1 was in a state in which many void-type defects were formed. However, it can be seen that the reduced graphene of Example 1 forms a complete sheet without visible pore defects. Ethanol (C ₂ H ₅ OH) used as a dispersion is a precursor that supplies carbon, and graphene is formed at the defect position of graphene oxide at the moment copper nanopowder formed by electric explosion meets graphene oxide. Therefore, since the pore defect was healed by the graphene formed at the defect location, it is determined that no defect in the form of a pore was found in the sample of Example 1.

<Evaluation of physical properties of reduced graphene/metal nanocomposite powder>

5 is a scanning electron microscope (SEM) image of (a) Example 3 metal and metal oxide nanopowder and (b) Example 1 graphene-metal nanocomposite powder form.

Referring to FIG. 5 , it can be seen that both the metal and metal oxide powders of Example 3 and the nanocomposite powder of Example 1 have a size distribution of several tens of nanometers. In addition, in the SEM image of the graphene-metal nanocomposite powder of Example 1, graphene combined with the metal nanopowder can be confirmed.

6 is a result of analyzing the nanocomposite powder of Examples 1 to 6 and graphene oxide of Comparative Example 1 by Raman spectroscopy.

Referring to FIG. 6, in the Raman spectra of Examples 1 and 4, three main D peaks (1354.9 cm ^-1 ), G peaks (1580.2 cm ^-1 ), and 2D peaks (2693.3 cm ^-1 ) of graphene are all observed Through this, it can be confirmed that the film covering the metal nanopowder in FIG. 5 is graphene.

In the case of the copper and copper oxide nanopowder of Example 3 and the nickel and nickel oxide nanopowder of Example 6, the carbon-related G peak was not detected, and the metal oxide-related peak was detected. In the case of the carbon-coated copper nanopowder of Example 2, metal oxide-related peaks appeared, and D peak (1354.9 cm ^-1 ) and G peak (1580.2 cm ^-1 ) appeared in the carbon material together with fluorescence peaks.

In addition, in the case of the carbon-coated nickel nanopowder of Example 5, a D peak (1354.9 cm ⁻¹ ) and a G peak (1580.2 cm ⁻¹ ) of graphene were detected without metal oxide and fluorescence peaks. Summarizing the above results, in the case of Examples 2 and 5, although a carbon layer was formed on the metal nanopowder through electrical explosion, the signal of the 2D peak represented by the double resonance phenomenon of graphene was weak, so the crystallinity falling can be seen.

In the case of the nanocomposite powders of Experimental Example 1 and Example 4, since it shows a strong 2D peak, it means that the crystallinity of graphene is good. This is consistent with the results of the transmission electron microscope image of FIG. 4 confirming that defect healing occurs during the manufacturing process of reduced graphene by electric explosion.

7 is an experimental example of the present invention, and is a result of analyzing the nanocomposite powders of Example 1, Example 3, Example 4 and Example 6 by X-ray diffraction (XRD) method.

Referring to FIG. 7, (a) In the case of Experimental Example 1 and Example 3, the metal nanopowder was composed of copper oxide (Cu ₂ O) and copper (Cu). (b) In the case of Experimental Example 4 and Example 6, it was confirmed that the metal nanopowder was composed of nickel oxide (NiO) and nickel (Ni) nanopowder.

In the case of Example 3 and Example 6 in which no organic solvent was used, the specific gravity of the metal oxide accounted for a relatively large specific gravity. In Examples 1 and 4 using an organic solvent, the specific gravity of the metal oxide decreased as the metal nanopowder was combined with the reduced graphene. That is, when the composite nanopowder is produced by the electric explosion method of the present invention, it can be seen that the specific gravity of the metal oxide can be controlled by controlling the mixed solution.

8 is an experimental example of the present invention, the results of measuring the conductivity of Example 1 and Example 2 by the powder resistance measurement method, and the powder resistance measurement result was linearized (plotted) as a conductivity change according to the density of the powder.

Referring to FIG. 8 , in the case of the carbon-coated copper nanopowder of Example 2, a conductivity value of 73.2 S/m was obtained at a density of 3.5 g/cc. On the other hand, in the case of the graphene-copper nanocomposite powder of Example 1, the conductivity value was 166.2 S/m at the same density of 3.5 g/cc.

This is an increase in conductivity of about 127%. As shown in the image shown in the structure of the nanocomposite powder in FIG. considered to be improved.

On the other hand, Example 3 is a copper and copper oxide nanopowder, and since it contains copper oxide, the resistance is high, so the conductivity was not measured by the powder resistance measurement method.

9 is an experimental example of the present invention, and is a result of analyzing electromagnetic wave shielding characteristics using the nanocomposite powders of Examples 1 and 4. In the electromagnetic wave shielding characteristic analysis method, the powder of each sample was pressed into a disk shape having a diameter of 3 cm and a thickness of 1000 mm, and then the electromagnetic wave shielding rate was measured in a high frequency region (X band) of 8 GHz to 12 GHz. As a result, the graphene-nickel nanocomposite powder of Example 4 showed shielding efficiency of 83.1 dB on average.

As described above, in the method for manufacturing a graphene nanocomposite powder according to an embodiment of the present invention, a graphene nanocomposite powder cured by 95% or more can be easily prepared in a single process using an electric explosion device in a liquid. It is possible to save process cost and time by reducing the process steps of the graphene nanocomposite powder compared to the prior art. In addition, by realizing reduced graphene with almost all defects compared to the prior art, conductivity is significantly improved compared to metal nanopowder, and thus it can be applied as a conductive filler material.

Although the present invention has been described with reference to the embodiments shown in the drawings, this is only exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical scope of protection of the present invention will be determined by the technical spirit of the appended claims.

10: Excess gas outlet
20: high voltage electrode
30: conductive wire (explosive part)
40: wire guide
50: ground electrode
60: mixed solution in which graphene oxide powder is dispersed
70: ultrasonic powder dispersion device
80: chamber
100: electric explosion device

Claims (11)

charging a metal wire into a mixed solution in which graphene oxide is dispersed; and
Forming a composite structure by reacting a nanopowder containing a metal or metal oxide formed by electrically detonating the metal wire by applying energy to the metal wire loaded in the mixed solution and the graphene oxide. do,
Forming the composite structure,
Forming the composite structure by combining the nanopowder and the reduced graphene oxide by forming reduced graphene oxide in which the graphene oxide is reduced and the defect is healed due to the exploding metal wire; Including,
Manufacturing method of graphene nanocomposite powder. According to claim 1,
The composite structure,
The reduced graphene oxide in the form of a thin film is bonded between the nanopowder to have a structure in which the nanopowder surrounds the reduced graphene oxide.
Manufacturing method of graphene nanocomposite powder. According to claim 1,
The nanopowder has a size of 100 nm or less (greater than 0),
Manufacturing method of graphene nanocomposite powder. According to claim 1,
Forming the nanopowder,
Applying a pulse voltage equal to or greater than the energy required for sublimation of the metal wire in consideration of the size of the metal wire loaded in the mixed solution,
Manufacturing method of graphene nanocomposite powder. According to claim 4,
In the step of applying the pulse voltage, applying a pulse voltage (V) value calculated by the following relational expression 1 expressed in consideration of the sublimation energy (E) of the metal wire and the capacitor capacity (C) of the device,
Manufacturing method of graphene nanocomposite powder.
[Relationship 1]
E=1/2CV ²
(E is the sublimation energy, C is the capacitance, and V is the pulse voltage) According to claim 1,
The mixed solution is mixed using a stirrer after dispersing the graphene oxide on an organic solvent, optionally further containing distilled water,
Manufacturing method of graphene nanocomposite powder. According to claim 6,
The organic solvent is acetone, pyridine, methyl ethyl ketone, methyl alcohol, ethyl alcohol, isopropyl alcohol, butyl alcohol, ethylene glycol, polyethylene glycol, tetrahydrofuran, dimethylformamide, dimethylacetamide, N-methyl- Any one or two selected from 2-pyrrolidone, hexane, cyclohexanone, toluene, chloroform, dichlorobenzene, dimethylbenzene, trimethylbenzene, methylnaphthalene, nitromethane, acrylonitrile, octadecylamine, aniline and dimethylsulfoxide Including a mixture of more than one,
Manufacturing method of graphene nanocomposite powder. According to claim 1,
The reduced graphene oxide has an oxygen content of 5% or less (greater than 0),
Manufacturing method of graphene nanocomposite powder. According to claim 1,
In the reduced graphene oxide, more than 95% of the pore defects are healed by graphene growth in the region where the pore defects of the graphene oxide exist.
Manufacturing method of graphene nanocomposite powder. According to claim 1,
The diameter of the metal wire has a diameter of 1 mm or less (greater than 0), and the length of the metal wire has a length of 10 cm or less (greater than 0).
Manufacturing method of graphene nanocomposite powder. According to claim 1,
The metal wires include manganese (Mn), copper (Cu), chromium (Cr), iron (Fe), nickel (Ni), cobalt (Co), gold (Au), silver (Ag), and platinum (Pt). Including any one or a mixture of two or more of the transition metal elements,
Manufacturing method of graphene nanocomposite powder.

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