KR20130112987A - Gamma-ray-induced reduction method of graphene oxide and the fabrication of the manufactured graphene using the thereof - Google Patents

Abstract

PURPOSE: A method of manufacturing graphene is provided to be environmentally friendly, to reduce energy consumption and to mass produce by not requiring heating process and harmful reducing agent. CONSTITUTION: A method of manufacturing graphene manufactures graphene reduced by irradiating graphene oxide solution with gamma-ray. The graphene oxide solution includes graphene oxide dispersed in the solvent. The solvent is one two or greater kinds selected from organic solvent, protonic solvent or a mixture thereof. [Reference numerals] (AA) Graphite; (BB) Oxidation reaction; (CC) Graphene oxide solution; (DD) Irradiating gamma-ray; (EE) Reduced graphene solution

Description

Gamma-ray-induced reduction method of graphene oxide and the fabrication of the manufactured graphene using the IEC}

The present invention relates to a method for reducing graphene oxide using gamma rays and to graphene prepared therefrom. More specifically, graphene oxide is prepared through gamma irradiation after preparing a graphene oxide solution by peeling graphite through an oxidation reaction. It relates to a method for producing graphene by reducing the.

Graphene is a new material of dreams, a material that has attracted a lot of attention lately. It is a material that separates a layer of graphite having an atomic structure in which carbons are arranged in planes arranged like honeycomb hexagonal nets. Such graphene has very excellent thermal, mechanical and electrical properties, and thus has great potential for applications in various electric, bio, and energy fields such as ultrafast transistors, flexible memory devices, biomimetic devices, and solar cells.

In order to realize this application possibility, a technology that can manufacture high-quality graphene quickly and in large quantities in large quantities and economically, while using low energy consumption is required, and many studies have been conducted worldwide to develop such a technology. .

The graphene manufacturing techniques developed so far are mechanical exfoliation, which is a method of overcoming and removing the weak interaction between graphene layers by mechanical force in the graphite crystal, and then exfoliated through chemical oxidation from the graphite crystal. Chemical exfoliation method to reduce to fin, chemical vapor deposition method to synthesize graphene by forming carbon and carbide alloys at high temperature or a transition metal that adsorbs carbon well as catalyst, and at high temperature The carbon adsorbed or contained in the crystals can be classified into four types by the epitaxy method of growing graphene to grow graphene.

Among these methods, chemical exfoliation, which is easy to mass-produce and has various applications, is getting the most attention, and recently, graphene oxide is prepared by exfoliation from such graphite crystals through chemical oxidation. A lot of researches on the essential and important reduction method in the chemical exfoliation method to reduce to pin.

Until now, reducing by heating in the presence of a reducing agent such as hydrazine hydrate (hydrazine hydrate), hydroquinone, sodium borohydride (sodium borohydride), reducing by heating over 200 ℃ in an inert gas or reducing gas environment Various methods have been developed, such as a method, basic aqueous solution, distilled water or dimethylformamide (DMF), dimethylacetamide (DMAc), N-methylpyrrolidinone (NMP), and the like in general in organic solvents. . However, the method using a reducing agent such as hydrazine hydrate, hydroquinone, sodium borohydride, etc. is not suitable for mass production because the reducing agent used is not harmful and environmentally friendly and is not suitable for mass production. Since it is made through abnormal heating, it is difficult to control the degree of reduction, and thus there is a problem that conductivity and solubility control are not easy.

In addition, the method of reducing graphene by heating to 200 ° C. or higher in an inert or reducing gas environment is required to be heated to a high temperature of 200 ° C. or higher, so that energy consumption is large, and mass production is difficult, and conductivity and solubility control are not easy, and thus reproducibility is achieved. There is an inconsistent problem.

Reduction by heating to 100 ° C or above in organic solvents such as basic aqueous solution, distilled water, dimethylformamide (DMF), dimethylacetamide (DMAc), and N-methyl pyrrolidone (NMP) Although the method is more advanced than the above methods, it is not suitable for continuous process and mass production because it is manufactured by heating in the same way, and it is difficult to mass production and control of conductivity and solubility like the above methods because it is reduced by heating. .

In the prior art of the graphene manufacturing method US Patent Publication No. 201000237296 (2010.09.23) is a graphene oxide by controlling the temperature and reducing agent of the solution by dispersing the graphene oxide in a high boiling point solvent having a boiling point of 200 ℃ or more, A method of reducing to graphene is described. However, this method requires a large energy consumption in order to maintain the temperature above 200 ° C, and requires a reduced pressure when the temperature is below 200 ° C, and the reduced graphene conductivity is not constant. there was.

In addition, Korean Patent Publication No. 2011-0101668 (2011.09.16) proposes a method for preparing graphene having excellent dispersibility in an organic solvent by adding and reducing phenyl hydrazine to graphene oxide. However, since a reducing agent such as phenyl hydrazine is harmful and not environmentally friendly, it may be detrimental to mass production, and there is a problem in that an additional process of additionally removing the reducing agent remaining after graphene production by washing is performed.

Therefore, in order to solve the above problems, and to manufacture graphene applicable to various organic electronic devices such as solar cells, organic light emitting devices, and nonvolatile organic memory devices, manufacturing and handling are easy with low manufacturing costs and simple manufacturing processes. It is easy to study how to prepare graphene with improved thermal, mechanical and electrical properties.

United States Patent Application Publication No. 201000237296 (2010.09.23) Republic of Korea Patent Publication No. 2011-0101668 (2011.09.16)

The present invention is eco-friendly by producing a graphene by reducing gamma irradiation at room temperature without using a harmful reducing agent, easy to mass production of graphene, excellent process reproducibility, and easy to control the reduction and conductivity of the graphene It is an object to provide a manufacturing method.

In addition, an object of the present invention to provide a graphene prepared by the reduction method.

Another object of the present invention is to provide an electronic device including a conductive thin film, a transparent electrode, a memory device, a solar cell, and an organic light emitting device using the graphene, and a biodevice including a biosensor, a biochip, and a neuron chip. .

The present invention provides a graphene manufacturing method, characterized in that to produce a reduced graphene by irradiating gamma rays to the graphene oxide solution to achieve the above object.

In addition, it provides a graphene prepared by the above method.

According to the method of reducing the graphene oxide using the gamma ray of the present invention and the graphene prepared therefrom, the heating process and the harmful reducing agent are not required compared to the existing methods, so that mass production is possible, energy consumption is small, and environmentally friendly advantages. There is this. In addition, since the degree of reduction can be easily controlled according to the gamma-ray dose to be irradiated, there is an advantage that the conductivity and the degree of reduction can be easily controlled.

In addition, the reduced graphene solution is present in a very stable colloidal state without precipitation, there is an advantage that can be utilized for solution blending, coating and inkjet printing through a simple dilution without any post-treatment. Therefore, the present invention may be very useful in various electronic device fields such as organic light emitting devices, solar cells, memory devices, etc., as well as bio device fields such as neuron chips, biosensors, and biochips.

1 is a schematic diagram showing a method for reducing graphene using gamma rays according to the present invention.
2 is a photograph showing a solution state before (a) gamma-irradiation and (b) gamma-irradiation of Example 1 of the present invention.
Figure 3 is a photograph showing the state of the graphene solution reduced by (a) reduction by heating of Comparative Example 1, (b) reducing agent and heating of Comparative Example 2 and (c) gamma irradiation of Example 1 to be.
FIG. 4 is a graph showing XRD measurement results of graphene oxide before (a) graphite, (b) gamma irradiation of Example 1, and (c) gamma irradiation of Example 1. FIG.
5 is a graph showing conductivity according to gamma-irradiation doses of Examples 2 to 7 of the present invention.
FIG. 6 is a photograph of a conductive film prepared from the graphene solution of Example 8 of the present invention, and FIG. 7 is a photograph showing a result of a simple electric circuit implementation experiment using FIG. 6.
8 is a photograph showing a solution state before (a) gamma-irradiation and (b) gamma-irradiation of Example 22 of the present invention.
9 is a graph showing the results of UV-VIS spectroscopy before (a) gamma-irradiation and (b) gamma-irradiation of Example 22 of the present invention.

Hereinafter, a preferred embodiment and a physical property measuring method of the graphene oxide reduction method using the gamma ray of the present invention and the graphene prepared therefrom will be described in detail. The present invention may be better understood by the following examples, which are for the purpose of illustrating the present invention and are not intended to limit the scope of protection defined by the appended claims.

It relates to a graphene manufacturing method characterized in that to produce a reduced graphene by irradiating gamma rays to the graphene oxide solution.

Specifically, the gamma ray is characterized by satisfying the conditions of the following [Formula 1] and [Formula 2].

[Formula 1]

1 ≤ Rγ ≤ 10 kGy / hr

[Formula 2]

10 ≤ Tγ≤ 1000 kGy

(In Formula 1, Rγ is a gamma-ray irradiation dose rate, and in Formula 2, Tγ is a gamma-ray total irradiation amount.)

In addition, the graphene oxide solution is characterized in that the graphene oxide is dispersed in a solvent, the solvent is one or two selected from an organic solvent containing nitrogen, a protonic solvent or a mixture thereof It is characterized by the above.

The nitrogen-containing organic solvent is dimethylformamide (dimethylformamide, DMF), dimethylacetamide (dimethylactamide, DMAc), N-methyl pyrrolidinone (NMP), pyridine, trimethylamine (trimethylamine ), The protonic solvent is characterized in that it comprises water, (C1-C7) lower alcohol.

In addition, the concentration of the graphene oxide solution is characterized in that 0.001 to 0.5 g / ml.

The graphene oxide solution further comprises a dispersant, wherein the dispersant is one or two or more selected from the group of anionic surfactants, cationic surfactants, nonionic surfactants or amphoteric surfactants.

In addition, the graphene oxide solution in the present invention may further include a metal nanoparticle precursor.

The metal nanoparticle precursor is scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu) , Zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), tungsten (W), ruthenium (Ru), palladium (Pd), indium (In), tin (Sn), platinum (Pt) , Silver (Ag), gold (Au) is characterized in that it is selected from a compound comprising a metal component or a mixture thereof.

In addition, the metal nanoparticle precursor is characterized in that it is added in a concentration of 1 x 10 ^-6 to 1 x 10 ^-2 mol / L.

Hereinafter, one aspect of the present invention will be described in detail.

1 is a schematic diagram showing a method for reducing graphene oxide using gamma rays according to the present invention. Referring to Figure 1, it is preferable to prepare a graphene oxide solution by oxidizing graphite (graphite), and to reduce the graphene oxide by irradiating gamma rays to it.

The solvent for preparing the graphene oxide solution is not particularly limited as long as it is an organic solvent capable of dispersing graphene, but is preferably selected from an organic solvent containing nitrogen, a protonic solvent, or a mixture thereof. One or two or more kinds can be exemplified. In particular, organic solvents containing nitrogen include dimethylformamide (DMF), dimethylacetamide (DMAc), N-methyl pyrrolidinone (NMP), pyridine, trimethylamine ( trimethylamine), and may include water or a lower alcohol having 1 to 7 carbon atoms as a protonic solvent. It is also effective to use the solvents alone or in combination.

 In addition, the concentration of the graphene oxide solution is preferably 0.001 to 0.5 g / ml, more preferably 0.01 to 0.1 g / ml is effective. When the concentration of the graphene oxide solution is less than 0.001 g / ml is included in the graphene oxide too small, may cause a problem that the graphene reduction efficiency is lowered, if the concentration of the graphene oxide solution is more than 0.5 g / ml There may be a problem that precipitation occurs due to the aggregation of graphene oxide.

In order to more effectively disperse the graphene oxide in the solvent may further comprise a dispersant. The dispersant is not particularly limited as long as it is a commonly used surfactant, and one or two kinds selected from the group consisting of anionic surfactants, cationic surfactants, nonionic surfactants or amphoteric surfactants can be exemplified. For example, soap (sodium fatty acid), monoalkyl sulfate, alkylpolyoxyethylene sulfate, alkylbenzenesulfonate, monoalkylphosphate, monoalkyltrimethylammonium salt, dialkyldimethylammonium salt, alkylbenzylmethylammonium salt, alkylsulfobetaine, alkyl Carboxybetaine, polyoxyethylene alkyl ether, fatty acid sorbitan ester, fatty acid diethanolamine, alkyl monoglyceryl ether, alkyl ether phosphate, polyoxyethylene aryl ether phosphate, polyoxyethylene alkyl phosphate, polyoxyethylene alkyl amine, polyethylene glycol mono (tri-styryl-phenyl) ether, a non-ionic fluorocarbon surfactant ^{(nonionic fluoro surfactant;? DuPont TM} Capton FS-60, FS-61, FS-63), anionic fluorinated surfactant (anionic fluoro surfactant; DuPont ^TM Capton ^{? F-30, FS-31} , FS-3100, FS-35), Woellner 's Sapetin D27, rain St. amphoteric surfactant (amphiphilic surfactan t; one or two selected from BASF's Pluronic F127, F108, F88, F68, P123, P105, L44).

The graphene oxide solution may be dispersed by a conventionally used dispersing method, and more preferably, it is effective to disperse using ultrasonic waves. This is to prepare the graphene oxide solution into a uniform and stable colloidal phase without aggregation and precipitation of graphene oxide.

In addition, the present invention is preferably reduced by irradiating gamma rays to the graphene oxide solution. As shown in FIG. 1, by irradiating gamma rays to a solution in which graphene oxide is dispersed, graphene oxide may be easily reduced to graphene by a simple method without a separate reducing agent.

 Specifically, the gamma ray preferably satisfies the conditions of the following [Formula 1] and [Formula 2].

[Formula 1]

1 ≤ Rγ ≤ 10 kGy / hr

[Formula 2]

10 ≤ Tγ≤ 1000 kGy

(In Formula 1, Rγ is a gamma-ray irradiation dose rate, and in Formula 2, Tγ is a gamma-ray total irradiation amount.)

When the Rγ is less than 1 kGy / hr or the Tγ is less than 10 kGy, the reduction efficiency of graphene oxide may be reduced, and the Rγ is more than 10 kGy / hr, or the Tγ is more than 1000 kGy. In this case, it may occur that the reduction efficiency is no longer increased compared to the gamma radiation dose irradiated.

In addition, another embodiment of the present invention is characterized in that it further comprises a metal nanoparticle precursor in the graphene oxide solution. The metal nanoparticle precursor is added to form the doped metal nanoparticles simultaneously with the reduction of the graphene oxide.

Specifically, the process of preparing the graphene oxide solution is the same as described above in the first aspect, it is effective to further include a metal nanoparticle precursor in the prepared graphene oxide solution. The metal nanoparticle precursor is scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu) , Zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), tungsten (W), ruthenium (Ru), palladium (Pd), indium (In), tin (Sn), platinum (Pt) , A compound containing a metal component selected from silver (Ag), gold (Au) or a mixture thereof, and more preferably a compound containing a metal component of silver (Ag) or gold (Au). Is effective.

In addition, the concentration of the metal nanoparticle precursor is preferably 1 x 10 ^-6 to 1 x 10 ^-2 mol / L, more preferably 1 x 10 ^-4 to 1 x 10 ^-3 mol / L. to be. By irradiating gamma rays to the graphene oxide solution in which the metal nanoparticle precursors are dispersed together, the metal nanoparticles are preferably doped simultaneously with the reduction of the graphene oxide. The gamma-irradiation is effective under the same conditions as in the above-described aspect.

The present invention provides graphene prepared by the above method. In addition, the graphene may include doped with metal nanoparticles.

In addition, the graphene prepared according to the manufacturing method of the present invention may be used as a conductive thin film, a transparent electrode, a memory device, a solar cell and an organic light emitting device, but is not limited thereto.

Hereinafter, the present invention will be described in detail by way of examples. However, the following examples are illustrative of the present invention, and the present invention is not limited by the following examples.

Example 1

DMF  Solvent Grapina  Oxide Solution Preparation

1.2 g of graphite (Graphite, Baycarbon, SP-1) was added to 1.2 g of potassium disulfide (K ₂ S ₂ O ₈ , Aldrich) and 1.2 g of phosphorus pentoxide (P ₂ O ₅ , Aldrich) was added to 5 ml of sulfuric acid solution, which was completely dissolved, and reacted at 80 ^° C. for 4:30 minutes, followed by pretreatment, followed by filtration and drying at room temperature. Then, 1.2 g of pretreated graphite was added to 500 ml of 46 ml of sulfuric acid (Aldrich) at 0 ^o C and mixed. Then, 6 g of potassium permanganate (KMnO ₄ , Aldrich) was added and stirred at room temperature for 2 hours. React. 200 ml of water was added to the terminated solution, and after stirring, 9 ml of 30% hydrogen peroxide was added to remove potassium permanganese. The solution was neutralized by washing with DI water eight times using a centrifuge, and the residues such as acids and salts were removed by dialysis using a semipermeable membrane (MWCO 6,000 ~ 8,000) and dried to remove powdered graphene oxide. Got it. 1 g of the graphene oxide was completely dispersed by sonication in 100 ml of dimethylformamide (DMF) solvent to prepare a graphene oxide solution having a concentration of 1 mg / ml.

Reduced by gamma irradiation Grapina  Produce

Cobalt-60 in the graphene oxide solution prepared in the step Using a gamma ray generator (MDS, Nordion), the reduced graphene solution was prepared through irradiation of gamma rays at a dose rate of 3 kGy / hr at 400 kGy.

EXAMPLES 2-7

Gamma rays were carried out in the same manner as in Example 1 except that the graphene oxide was reduced by irradiation of 50 kGy, 100 kGy, 200 kGy, 300 kGy, 400 kGy and 500 kGy at dose rates of 5 kGy / hr, respectively.

[Example 8]

Gamma rays were irradiated at a dose rate of 8 kGy / hr to carry out the same method as in Example 1 except that graphene oxide was reduced.

EXAMPLES 9-13

The preparation of the graphene oxide solution was carried out in the same manner as in Examples 3 to 7, except that the solvent was used dimethylacetamide.

[Examples 14-18]

Except for using N-methylpyrrolidone as a solvent in the preparation of the graphene oxide solution was carried out in the same manner as in Examples 3 to 7, respectively.

[Example 19]

Except for using water as a solvent in the preparation of the graphene oxide solution was carried out in the same manner as in Example 6.

[Example 20]

The preparation of the graphene oxide solution was carried out in the same manner as in Example 6, except that methanol was used as the solvent.

Example 21

Except for using ethanol as a solvent in the preparation of the graphene oxide solution was carried out in the same manner as in Example 6.

[Example 22]

Silver nanoparticles  With precursor Grapina  Preparation of oxide solution

A graphene oxide solution was prepared in the same manner as in Example 6, except that silver nitrate (AgNO ₃ , Showa chemicals), which is a silver nanoparticle precursor of 1 × 10 ⁻² mol / L, was additionally added.

[Example 23]

Gold nanoparticles  With precursor Grapina  Preparation of oxide solution

The graphene oxide solution was prepared in the same manner as in Example 6 except that 1 × 10 ⁻² mol / L of gold chloride nanoparticle precursor (HAuCl ₄ , Aldrich) was additionally added.

Comparative Example 1

It was carried out in the same manner as in Example 1 except that it was reduced by heating at 100 ° C. for 2 hours without gamma irradiation and addition of a reducing agent.

Comparative Example 2

Add 50% by weight of hydrazine monohydrate (65%, Sigma Aldrich) to the amount of graphene oxide without gamma irradiation. ^{o It} was carried out in the same manner as in Example 1 except that it was reduced by heating for 1 hour at C.

[Comparative Example 3]

Except for the addition of 50% by weight of hydrazine monohydrate (65%, Sigma Aldrich) to the amount of graphene oxide without gamma irradiation and reduced by heating at 95 ^o C for 1 hour. It was done in the same way.

[Table 1]

[Experimental Example 1]

Grapina  Before and after gamma irradiation of oxide solution Precipitation  Confirm

FIG. 2 shows the solution state before (a) and after gamma irradiation (b) of 400 kGy gamma irradiation in Example 1. As shown in FIG. 2, the graphene oxide solution prepared before gamma irradiation is A light brown stable state in which no pin oxide was precipitated was maintained, and the reduced graphene solution was changed to black after irradiating 400 kGy gamma rays, but remained stable without precipitation. In addition, as shown in FIG. 3, the solution reduced by heating by (a) Comparative Example 1 or by (b) heating by using a conventional hydrazine monohydrate reducing agent of Comparative Example 2 ( c) Unlike the graphene solution reduced in Example 1, it was confirmed that precipitation occurs. These results confirmed that the graphene oxide was well reduced without precipitation by gamma irradiation.

 [Experimental Example 2]

Graphite  And Example  Before and after gamma irradiation Grapina  X-ray diffraction  analysis

Graphite, graphene before gamma-irradiation of Example 1, and graphene after gamma-irradiation of Example 1 were analyzed as a comparative example to analyze the change of the crystal state of graphene oxide according to the reduction by gamma irradiation. It was analyzed using a line diffractometer (X-Ray diffractometer, HR-XRD, model: X'Pert PRO Multi Purpose X-Ray Diffractometer, manufacturer: PANalytical, Netherlands), the results are shown in FIG. As shown in Figure 4, (a) in the case of graphite (Graphite) there was a characteristic peak at 26.4 ^o showing the distance between the layers 3.37 ,, (b) in graphene oxide disappears the characteristic peak of graphite and the distance between layers There was a new peak at 11.10 ^o indicating 7.76 μs. This means that the structure of the graphite was modified by the oxidation reaction and completely peeled off to form graphene oxide. On the contrary, (c) in the case of graphene reduced by gamma irradiation of Example 1, it was confirmed that the characteristic peak was present at 22 ^o larger than the interlayer distance of graphite and smaller than the graphene oxide. This result is believed to be due to the reduction of the functional groups present in the graphene oxide to the crystalline structure during the reduction by gamma irradiation.

[Experimental Example 3]

Reduced by gamma irradiation Grapina  Conductivity measurement

In Examples 2 to 7, the conductivity of the graphene reduced at each gamma-irradiation was measured using a resistance meter (MCPP-T610, Mitsubishi Chemical Corporation, Japan) and the results are shown in FIG. 5. As shown in FIG. 5, as the absorbed dose increased, the conductivity of the reduced graphene increased to 21 S / cm. This means that the conductivity of graphene oxide can be easily controlled by the gamma radiation dose because the conductivity of graphene oxide depends on the gamma radiation dose.

[Experimental Example 4]

Reduced Grapina  Film manufacturing and electrical circuit implementation using the same

In Example 8, a graphene solution reduced at 400 kGy was prepared by filtration through an Anodisc filtration membrane (diameter: 47 mm, 0.2 μm pores, Sigma Aldrich), and a simple electric circuit implementation experiment was performed. The results are shown in FIGS. 6 and 7. Indicated. As shown in Figure 6 and 7, successfully prepared 13μm freestanding film organic light emitting bulb (LED, size: 5 mm (L) x 5 mm (W) x 2mm (H), white light, Korea Photonics Technology Institute ) Was connected to a 9 V battery (rocket) and the film produced therebetween, it was confirmed that the organic light emitting bulb is lit by the electricity flows through the produced film. Based on these results, it was confirmed that the reduced graphene shows an industrially applicable conductivity.

Therefore, according to the above results, by forming the graphene by the method of reducing the graphene oxide using the gamma ray of the present invention, it is possible to manufacture a large area of graphene in a low cost and simple process, and excellent graphene Could be manufactured.

[Experimental Example 5]

Reduced Silver nanoparticles  Contained Grapina  Formation check and conductivity measurement

FIG. 8 shows the state of the solution after irradiation of (a) 400 kGy gamma ray (b) of gamma ray of Example 22, and similar to that shown in FIGS. 2 (a) and 2 (b), before irradiation of gamma ray The graphene oxide solution containing silver nitrate (AgNO ₃ ) remained a light brown stable state in which no graphene oxide was precipitated. The color of the reduced solution changed to black after irradiating 400 kGy gamma rays but stable without precipitation. Existed in the state. Through these results, gamma-ray irradiation confirmed that the formation of silver nanoparticles and graphene oxide were well reduced without precipitation. In addition, UV-VIS analysis (model name: S-3100, manufacturer: Scinco, Korea) before and after 300 kGy gamma-ray irradiation was performed to confirm whether silver nanoparticles were formed in the reduced graphene oxide solution in Example 22. It progressed and the result is shown in FIG. As shown in FIG. 9, before gamma irradiation, a typical band of graphene oxide was formed around 252 nm, and after gamma irradiation, graphene oxide was reduced, and a typical band moved to a long wavelength, and appeared at 267 nm. It was also confirmed that a band was formed newly around 410 nm which appeared when was formed. In addition, the conductivity of the graphene oxide containing silver nanoparticles reduced at 400 kGy was measured using a resistance measuring instrument (MCPP-T610, Mitsubishi Chemical Corporation, Japan), and the results were found to be 30 S / cm. Based on these results, gamma irradiation confirmed that the reduction of graphene oxide occurred well without precipitation with silver nanoparticle formation.

 Therefore, according to the above results, by forming the graphene by the method of reducing the graphene oxide using the gamma ray of the present invention, it is possible to manufacture a large area of graphene in a low cost and simple process, and excellent graphene Could be manufactured.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is clear that the present invention can be suitably modified and applied in the same manner.

Claims (13)

Graphene production method characterized in that to produce a reduced graphene by irradiating gamma rays to the graphene oxide solution. The method of claim 1,
The gamma ray is a graphene manufacturing method characterized in that it satisfies the conditions of the following [formula 1] and [formula 2].
1 ≤ Rγ ≤ 10 kGy / hr [Equation 1]
10 ≤ Tγ ≤ 1000 kGy [Equation 2]
(In Formula 1, Rγ is a gamma-ray irradiation dose rate, and in Formula 2, Tγ is a gamma-ray total irradiation amount.)
The method of claim 1,
The graphene oxide solution is characterized in that the graphene oxide is dispersed in a solvent,
The solvent is graphene manufacturing method characterized in that one or two or more selected from an organic solvent, a protonic solvent or a mixture containing nitrogen.
The method of claim 3, wherein
The nitrogen-containing organic solvent is dimethylformamide (dimethylformamide), dimethylacetamide (dimethylactamide), N-methylpyrrolidinone (N-methylpryrrolidone), characterized in that it comprises a pyridine (pyridine), trimethylamine (trimethylamine) Graphene manufacturing method.
The method of claim 3, wherein
The protonic solvent is a graphene manufacturing method, characterized in that containing water, (C1-C7) lower alcohol.
The method of claim 1,
The concentration of the graphene oxide solution is a graphene manufacturing method, characterized in that 0.001 to 0.5 g / ml.
The method of claim 1,
Graphene manufacturing method further comprises one or two or more dispersants selected from the group of anionic surfactants, cationic surfactants, nonionic surfactants or amphoteric surfactants.
Graphene prepared by the method of any one of claims 1 to 7 selected from.
The method of claim 8,
The graphene is for a conductive material of an electronic device or a bio device, and the electronic device includes a conductive thin film, a transparent electrode, a memory device, a solar cell, and an organic light emitting device. Graphene comprising a.
The method of claim 1,
The graphene oxide solution is a graphene manufacturing method characterized in that it further comprises a metal nanoparticle precursor.
The method of claim 10,
The metal nanoparticle precursor is scandium (Sc), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu) , Zinc (Zn), zirconium (Zr), niobium (Nb), molybdenum (Mo), tungsten (W), ruthenium (Ru), palladium (Pd), indium (In), tin (Sn), platinum (Pt) , Silver (Ag), gold (Au) is a graphene manufacturing method characterized in that it is selected from a compound containing a metal component or a mixture thereof.
The method of claim 10,
The metal nanoparticle precursor is a graphene manufacturing method, characterized in that added in a concentration of 1 x 10 ^-6 to 1 x 10 ^-2 mol / L.
Graphene doped with metal nanoparticles prepared by the method of any one of claims 10 to 12.

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