KR20210004025A - Apparatus for Surface Deposition of Graphene Oxide and Method for Surface Deposition using of it - Google Patents

Abstract

An embodiment of the present invention provides a graphene oxide lamination apparatus including a substrate portion, a nozzle portion, a gas supply portion, a gas pipe, and a resonator, and a lamination method using the same. According to an embodiment of the present invention, graphene oxide may be laminated on the surface of various materials using atmospheric-pressure plasma to impart excellent physicochemical properties such as high strength, electrical and thermal conductivity, and the like.

Description

Graphene oxide lamination apparatus and lamination method using the same {Apparatus for Surface Deposition of Graphene Oxide and Method for Surface Deposition using of it}

The present invention relates to a graphene oxide lamination apparatus and a lamination method using the same, and in more detail, a catalyst is not required and a graphene oxide lamination apparatus using atmospheric pressure plasma capable of laminating graphene oxide on the surface of various materials, and It relates to a lamination method using this.

Graphene oxide (Graphene Oxide) has high electrical and thermal conductivity and excellent mechanical properties, so its potential is recognized in various fields and is in the spotlight.

Accordingly, efforts have been made to improve the surface properties of materials by coating graphene oxide on the surfaces of various materials.

In particular, in the bio field, when the high blood compatibility of carbon and the reactivity of graphene oxide are used, various properties can be imparted to the surface of a biomaterial, so that there is a greater interest in surface coating using graphene oxide.

As a method of directly laminating graphene oxide, chemical vapor deposition is the most widely known method, and catalytic treatment and high-temperature heat treatment must be accompanied on the surface when performing this.

There is a simple process technology in which graphene oxide is directly deposited on the surface after activating carbon using high energy to reduce the hassle of such a process.

In the case of the conventional method of directly laminating graphene oxide on the surface, it was carried out under a specific gas atmosphere or in a vacuum chamber. In addition, there is a disadvantage that the process operation is not simple because the process of coating and removing the catalyst metal is absolutely necessary. In addition, there was a problem with variables and limitations in the process, such as a heat treatment process must be accompanied.

Therefore, in the present invention, a method for laminating graphene oxide and an apparatus therefor was devised, which does not require a catalyst using a high-density atmospheric pressure plasma that overcomes this disadvantage.

The technical problem to be achieved by the present invention is to provide a method for laminating graphene oxide using atmospheric pressure plasma and a laminating apparatus for the same, in which a catalytic metal is not used and thus a complicated process in the process is reduced.

The technical problem to be achieved by the present invention is not limited to the technical problems mentioned above, and other technical problems that are not mentioned can be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. There will be.

In order to solve the above problems, one aspect of the present invention is a substrate portion capable of rotational drive; A nozzle unit spaced apart from the substrate unit and capable of reciprocating front and rear, left and right, and up and down; A gas supply unit for supplying an inert gas and a carbon source gas to the nozzle unit to discharge a plasma for laminating graphene oxide; A single or a plurality of gas pipes through which the inert gas and the carbon source gas are introduced and passed from the gas supply unit to the nozzle unit; And a resonator electrically connected to the nozzle part outside the nozzle part and forming and activating atmospheric pressure plasma at a natural resonance frequency. It provides a graphene oxide lamination apparatus comprising a.

In an embodiment of the present invention, an effective movement distance measuring unit and a control unit may further include a rotation drive of the substrate unit and a moving direction of the nozzle unit according to the intensity of plasma discharged from the nozzle unit.

In an embodiment of the present invention, the frequency of the resonator may be applied to 500 MHz to 1000 MHz.

An aspect of the present invention includes preparing a substrate on the substrate portion; Forming and activating atmospheric pressure plasma by using the inert gas from the resonator by supplying an inert gas from a gas supply unit to a resonator through a gas pipe; And depositing the graphene oxide on the substrate by supplying a carbon source gas through a gas pipe from the gas supply unit and releasing the plasma and the carbon source gas from the nozzle unit when the plasma is stabilized. It provides a graphene oxide lamination method comprising a.

In an embodiment of the present invention, the inert gas may be any one of helium (He), nitrogen (N), or argon (Ar).

In an embodiment of the present invention, the amount of the carbon source gas may be provided at a rate of 10 sccm to 50 sccm.

In an embodiment of the present invention, in the step of laminating the graphene oxide, a separation distance between the substrate portion and the nozzle portion may be set to 5 mm to 10 mm.

In an embodiment of the present invention, in the stacking of the graphene oxide, the intensity of the plasma discharged from the nozzle may be controlled to control the rotational drive of the substrate and the moving direction of the nozzle.

According to an embodiment of the present invention, graphene oxide may be laminated on the surface of various materials to provide excellent physicochemical properties such as high strength, electrical and thermal conductivity.

In addition, since there is no need to perform it in a vacuum chamber under an inert gas atmosphere, the device and process method are simple, and time and cost can be saved.

In addition, since there is no need to form a catalytic metal layer, there is no need to involve the process of forming and removing a catalytic metal layer, and since graphene oxide with fewer defects and suppresses the generation of various carbon by-products can be stacked, there are few variables and restrictions in the process.

The effects of the present invention are not limited to the above effects, and should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a schematic diagram of a graphene oxide lamination apparatus according to an embodiment of the present invention.
2 is a flowchart illustrating a method of laminating graphene oxide according to an embodiment of the present invention.
3 is a graph measured by a Raman spectroscopy method of a graphene oxide layer stacked according to an embodiment of the present invention.
4 is a graph measured by Raman spectroscopy of the reduced graphene oxide layer stacked according to an embodiment of the present invention.

Hereinafter, the present invention will be described with reference to the accompanying drawings. However, the present invention may be implemented in various different forms, and therefore is not limited to the embodiments described herein. In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention, and similar reference numerals are assigned to similar parts throughout the specification.

Throughout the specification, when a part is said to be "connected (connected, contacted, bonded)" with another part, it is not only "directly connected", but also "indirectly connected" with another member in the middle. "Including the case. In addition, when a part "includes" a certain component, it means that other components may be further provided, rather than excluding other components unless specifically stated to the contrary.

The terms used in the present specification are only used to describe specific embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprise" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or a combination thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance.

In the present specification, "graphene" is a stack of one or more polycyclic aromatic carbon compounds arranged in one plane by connecting a plurality of carbon atoms by covalent bonds (sp ² bonds), and the covalent bond Carbon atoms connected by a bond form a 6-membered ring as a basic repeating unit, but it is also possible to further include a 3-membered ring, a 4-membered ring, a 5-membered ring, and/or a 6-membered ring or more. In addition, the graphene includes all of single crystal, polycrystalline or amorphous graphene, and refers to "pristine graphene" in which a functional group is not attached to the surface.

In the present specification, "graphene oxide" refers to a state in which carbon particles of graphene are oxidized by an acid, and an oxygen functional group is attached to the surface of the graphene.

Atmospheric pressure plasma according to the present invention is by atmospheric pressure chemical vapor deposition (APCVD), and the atmospheric pressure chemical vapor deposition is a type of chemical vapor deposition.

Plasma is the fourth state of a substance following solid, liquid, and gas. It is a state in which gas is weakly ionized by receiving energy, and exhibits completely different properties from the gas state.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

A graphene oxide lamination apparatus according to an embodiment of the present invention will be described.

1 is a schematic diagram of a graphene oxide lamination apparatus according to the present invention.

Referring to FIG. 1, the stacking apparatus according to the present invention includes a substrate portion 10, a nozzle portion 20, a gas supply portion 30, a gas pipe 33, and a resonator 40.

More specifically, the graphene oxide lamination apparatus includes a substrate unit 10 capable of rotational drive, a nozzle unit 20 disposed spaced apart from the substrate unit 10 and capable of reciprocating front and rear, left and right, and up and down, and the nozzle unit ( 20) a gas supply unit 30 supplying an inert gas and a carbon source gas so that the plasma 21 for stacking graphene oxide can be discharged, and the inert gas and the inert gas from the gas supply unit 30 to the nozzle unit 20 A single or a plurality of gas pipes 33 through which the carbon source gas is introduced and passed, and the nozzle part 20 are electrically connected to the nozzle part 20 outside the nozzle part 20, and the atmospheric pressure plasma 21 is formed at a natural resonance frequency. And a resonator 40 to activate.

In this case, the substrate portion 10 is a portion on which the substrate 11 is mounted, and the substrate portion 10 may include a rotation driving portion (not shown) so that the substrate 11 fixed to the substrate portion 10 is rotated. have.

Accordingly, the graphene oxide laminating apparatus according to the present invention can deposit graphene oxide on the entire surface of the material or on a desired portion.

Here, in the case of the nozzle unit 20 disposed to be spaced apart from the substrate unit 10, it is possible to reciprocate back and forth, left and right, and up and down.

The uniformity and thickness of the deposited portion may vary depending on the intensity of the plasma 21, so that the intensity of the plasma 21 is controlled to control the rotational drive of the substrate 10 and the reciprocating movement of the nozzle 20. Can be controlled.

At this time, an effective movement distance measuring unit (not shown) and a control unit (not shown) for switching the movement directions of the substrate unit 10 and the nozzle unit 20 according to the intensity of the plasma 21 discharged from the nozzle unit 20 (Not shown) may be further included.

Through this configuration, the user of the apparatus according to the present invention can control and control the driving of the substrate unit 10 and the nozzle unit 20. Therefore, graphene oxide can be evenly deposited on the surface of various materials, and the deposition thickness and direction can be arbitrarily set.

The gas supply unit 30 is divided into an inert gas supply unit 31 that allows the inert gas to be stored and discharged when necessary, and a carbon source gas supply unit 32 that allows the carbon source gas to be stored and released when necessary, and the gas supply unit ( The inert gas and carbon source gas discharged from 30) may be supplied individually or simultaneously.

The inert gas or carbon source gas discharged from the gas supply unit 30 can be introduced and moved to the nozzle unit 20 through a single or a plurality of gas pipes 33, and the inert gas introduced through the gas pipe 33 is The plasma 21 is formed and activated through the resonator 40 and is discharged to the nozzle unit 20.

The graphene oxide lamination apparatus according to the present invention can generate the plasma 21 at atmospheric pressure by designing the resonator 40. Using a microwave having a frequency higher than DC or AC power, for example, 500 MHz to 1000 MHz, for example, 900 MHz microwave, it is possible to generate the plasma 21 at a low voltage. The plasma 21 can be generated and maintained at atmospheric pressure with a low power of W.

If the plasma 21 is floated using an inert gas and a small amount of carbon source gas required for generating graphene oxide is precisely flowed, unnecessary hydrogen ions are removed from the plasma 21 and the carbon sp ² bonding required for graphene generation will be promoted. I can. Then, the plasma 21 may be directly applied to the surface of the substrate 11 to deposit graphene oxide. In the present invention, it is said that graphene oxide is deposited directly on the surface of the substrate 11, but the type of the substrate 11 is not limited, and it is not on the surface of materials having various types and various shapes other than the substrate 11 It has a characteristic capable of depositing graphene oxide.

Here, the inert gas may be characterized in that any one of helium (He), nitrogen (N) or argon (Ar).

In addition, the carbon source gas may promote the generation of graphene as a carbon source. This can be used without particular limitation as long as it can exist in a gas phase at a temperature of 300°C or higher. The gaseous carbon source gas is not limited as long as it is a compound containing carbon, and for example, a compound having 6 or less carbon atoms, a compound having 4 or less carbon atoms, or a compound having 2 or less carbon atoms may be used.

The carbon source gas is, for example, from the group consisting of carbon monoxide, methane, ethane, ethylene, methanol, ethanol, acetylene, propane, propylene, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene and toluene. You can use one or more of your choices. In addition, a solid carbon source such as polymethyl methacrylate may be used without limitation.

Meanwhile, the inert gas discharged from the gas supply unit 30 is introduced and moved into the gas pipe 33 to form and activate the plasma 21 through the resonator 40, and the resonator through the gas pipe 33 The inert gas moved to (40) has a very fast flow rate. The frequency of the resonator 40 is applied to maintain the fast flow rate of the inert gas, and at this time, the frequency is 500 MHz to 1000 MHz, for example, 900 MHz.

The plasma 21 formed in this way is discharged to the outside through the nozzle unit 20, and if the carbon source gas is precisely flowed with it, graphene oxide with less defects can be generated and laminated on the surfaces of various materials.

The graphene oxide lamination apparatus according to the present invention does not require a vacuum chamber. In addition, it is easy to manufacture with an equipment having a simple structure, and graphene oxide can be laminated on various materials using the atmospheric pressure plasma 21.

A method of laminating graphene oxide according to an embodiment of the present invention will be described.

2 is a flowchart illustrating a method of laminating graphene oxide according to the present invention.

Referring to FIG. 2, the graphene oxide lamination method according to the present invention includes a substrate 11 preparation step (S1), an atmospheric pressure plasma 21 formation step (S2), a carbon source supply and a graphene oxide lamination step (S3). Can contain

In a more detailed method of laminating graphene oxide according to the present invention, the step of preparing the substrate 11 on the substrate 10 (S1), the inert gas from the gas supply unit 30 to the resonator 40 through the gas pipe 33 The step of forming and activating the atmospheric pressure plasma 21 using the inert gas in the resonator 40 by supplying (S2) and when the plasma 21 is stabilized, the gas supply unit 30 through the gas pipe 33 It may include a step (S3) of stacking the graphene oxide on the substrate 11 by supplying a carbon source gas and releasing the plasma 21 and the carbon source gas from the nozzle unit 10 to the outside. have.

First, a step (S1) of preparing the substrate 11 on the substrate portion 10 is performed.

At this time, the substrate portion 10 serves to fix and control the movement of the substrate 11, so that the substrate 11 is properly maintained so that a distance between the substrate portion 10 and the nozzle portion 20 spaced apart from the substrate portion 10 Support. In addition, the substrate portion 10 includes a rotation driving portion capable of rotating the substrate 11 by 360° so that graphene oxide can be evenly deposited on the entire surface or a portion of the surface of the substrate 11.

Next, forming and activating atmospheric pressure plasma 21 using the inert gas from the resonator 40 by supplying an inert gas from the gas supply unit 30 to the resonator 40 through the gas pipe 33 (S2) Perform.

Here, the inert gas may be one of helium (He), nitrogen (N), or argon (Ar), and may be characterized by activating the plasma 21.

At this time, the resonator is an electron cyclotron resonance device that forms electron cyclotron resonance by applying microwave power, and is used to adsorb and diffuse carbon hydrogen radicals. diffuse) and nucleation occurs in the Van der Waals type of growth type, and graphene oxide is grown on the substrate layer without the catalyst layer. Therefore, the graphene oxide lamination apparatus according to the present invention has a characteristic that graphene oxide lamination is possible without a catalyst.

Next, when the plasma is stabilized, a step (S3) of supplying the carbon source gas from the gas supply unit to the nozzle unit through the gas pipe 33 is performed.

When the plasma 21 is stabilized, a small amount of carbon source gas is precisely flowed, and the carbon source gas may be characterized by promoting hydrogen ion removal and carbon sp ² bonding of graphene oxide. In addition, it may be characterized in that it is used for the purpose of removing defects of graphene oxide.

The gaseous carbon source gas can be any compound containing carbon, and for example, a compound having 6 or less carbon atoms, a compound having 4 or less carbon atoms, or a compound having 2 or less carbon atoms may be used.

The carbon source gas is, for example, from the group consisting of carbon monoxide, methane, ethane, ethylene, methanol, ethanol, acetylene, propane, propylene, butane, butadiene, pentane, pentene, cyclopentadiene, hexane, cyclohexane, benzene and toluene. You can use one or more of your choices.

Next, when the plasma 21 is stabilized, a carbon source gas is supplied from the gas supply unit 30 through the gas pipe 33 and the plasma 21 and the carbon source gas are externally supplied from the nozzle unit 10. A step (S3) of depositing the graphene oxide on the substrate 11 is performed by releasing it.

Here, the amount of carbon source gas may be supplied at a rate of 10 sccm to 50 sccm, and the inert gas and carbon source gas are mixed with the amount according to the surface energy, surface shape and bending conditions of the substrate 11 It may be characterized in that the ratio is adjusted.

The desired result can be obtained by flowing only a small amount of carbon source gas, but it is easy to uniformly form graphene oxide when the amount of carbon source gas is supplied at least 25 sccm. Therefore, the amount of the carbon source gas is not limited thereto as a portion that can be changed in consideration of the size, volume, and shape of the material.

One of the features of the present invention is that graphene oxide can be deposited on any material substrate 11 that does not require a catalyst.

It is also a feature of the present invention that the amount and mixing ratio of the gas can be adjusted according to the material of the substrate 11, and the separation distance between the nozzle from which the plasma 21 is discharged and the substrate portion 10 can be adjusted.

In this case, the separation distance between the substrate portion 10 and the nozzle portion 20 is preferably set to be, for example, 5 mm to 10 mm, for example, 7 mm.

If the distance between the substrate part 10 and the nozzle part 20 is closer than 5 mm, the intensity of the plasma 21 increases in the substrate part, so that the carbon source may not be deposited due to strong energy. In this case, the deposited thickness may be very thin, or the deposition may not be smoothly performed on the surface of the target.

In an embodiment of the present invention, after the carbon source supply and the graphene oxide lamination step (S3), plasma treatment may be performed on the stacked graphene oxide layer using an inert gas.

The inert gas may be any one of helium (He), nitrogen (N), or argon (Ar).

Through the step of plasma treatment using the inert gas, the graphene oxide may be reduced.

For example, a process of plasma treatment using an argon gas may be additionally performed on the stacked graphene oxide layer, and a reduced graphene oxide layer may be obtained through the plasma treatment.

The graphene oxide layered structure prepared as described above can be used for various purposes. Excellent conductivity and high uniformity of the film can be usefully used as a transparent electrode. When the layered structure on which graphene is formed is used as a transparent electrode, it exhibits excellent conductivity, and when used as a panel conductive thin film for various display devices, it is possible to improve conductivity and light transmission.

In addition, it can be used for channels for memory devices, sensors, and electronic paper. That is, since the graphene oxide layered structure has graphene on the insulating layer, it can be utilized as a gate electrode in various transistors such as FET transistors.

Example 1. Lamination of graphene oxide

A silicon wafer specimen having a size of 4 X 4 mm was prepared, and the surface of the silicon substrate was ultrasonically cleaned with ethanol for 10 minutes to remove contaminants.

A high-density atmospheric plasma generator PGS-300 (Expantech co., Suwon, Korea) operated by a 900 MHz dielectric resonator was used, and the plasma power of 240 W (900 MHz) using 4 L/m of argon as a plasma carrier. Occurred.

A mixed gas of methane (10%) and argon was used as a carbon source and introduced into the plasma at a rate of 60 sccm.

At this time, graphene oxide was stacked for 6 minutes with a separation distance of 7 mm between the substrate portion and the nozzle portion.

In this state, in order to evenly deposit graphene on the surface of the substrate, the rotation of the substrate fixed to the substrate and the reciprocating movement of the nozzle unit back and forth, left and right were simultaneously performed.

Through the above method, a silicon substrate on which the surface of the substrate was evenly deposited with graphene oxide was obtained.

Example 2. Lamination of reduced graphene oxide

The same process as in Example 1 was performed, and after the process of Example 1, plasma was formed and activated using only argon gas, and the graphene oxide layer deposited for 1 minute was plasma-treated.

Through the above method, a silicon substrate on which reduced graphene oxide was deposited was obtained.

Experimental example

Experiments were conducted to confirm physical properties of graphene oxide and reduced graphene oxide deposited on the silicon substrates of Examples 1 and 2 according to the present invention.

It is possible to confirm the qualitative and quantification of a substance through the Raman spectroscopy method. Accordingly, when the lamination apparatus according to the present invention and the method according to the present invention release plasma and carbon source gas on the substrate and laminated, the Raman spectroscopy measurement was performed to confirm that the material formed graphene or graphene oxide.

3 is a graph of graphene oxide prepared according to Example 1 measured by Raman spectroscopy.

3, the Yes and the position of the peak point to verify the pin D peak appearing on the first 1352 cm ^-1, G peak appearing on the second 1592 cm ^-1, 2685 cm ^-1 is a peak appearing 2D Yes It is somewhat irrelevant to the measurement of the pin.

It was confirmed that the material on the substrate of Example 1 was graphene oxide through the Raman measurement method.

4 is a graph of graphene oxide prepared according to Example 2 measured by Raman spectroscopy.

Referring to FIG. 4, the D peak appearing at 1352 cm ^-1 at the first of the peak point where graphene oxide can be identified, the G peak at 1610 cm ^-1 at the second, and the 2D peak at 2695 cm ^-1 are graphene oxide. It is somewhat irrelevant to the measurement of the pin.

It was confirmed that the material on the substrate of Example 2 was reduced graphene oxide through the Raman measurement method.

The above description of the present invention is for illustrative purposes only, and those of ordinary skill in the art to which the present invention pertains will be able to understand that it can be easily modified into other specific forms without changing the technical spirit or essential features of the present invention. will be. Therefore, it should be understood that the embodiments described above are illustrative in all respects and not limiting. For example, each component described as a single type may be implemented in a distributed manner, and similarly, components described as being distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims to be described later, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

10: substrate portion
11: substrate
20: nozzle part
21: plasma
30: gas supply unit
31: inert gas supply unit
32: carbon source gas supply unit
33: gas pipe
40: resonator

Claims (8)

A substrate portion capable of rotational drive;
A nozzle unit spaced apart from the substrate unit and capable of reciprocating front and rear, left and right, and up and down;
A gas supply unit for supplying an inert gas and a carbon source gas to the nozzle unit to discharge a plasma for laminating graphene oxide;
A single or a plurality of gas pipes through which the inert gas and the carbon source gas are introduced and passed from the gas supply unit to the nozzle unit; And
A resonator electrically connected to the nozzle part outside the nozzle part and forming and activating atmospheric pressure plasma at a natural resonance frequency;
Graphene oxide lamination apparatus comprising a. The method of claim 1,
The graphene oxide lamination apparatus further comprising: an effective movement distance measuring unit and a control unit for changing the rotational drive of the substrate unit and the moving direction of the nozzle unit according to the intensity of plasma discharged from the nozzle unit. The method of claim 1,
Graphene oxide lamination apparatus, characterized in that applying the frequency of the resonator 500 MHz to 1000 MHz. Preparing a substrate on the substrate portion;
Forming and activating atmospheric pressure plasma by using the inert gas from the resonator by supplying an inert gas from a gas supply unit to a resonator through a gas pipe; And
Depositing the graphene oxide on the substrate by supplying a carbon source gas from the gas supply unit through a gas pipe and releasing the plasma and the carbon source gas from the nozzle unit when the plasma is stabilized;
Graphene oxide lamination method comprising a. The method of claim 4,
The inert gas is any one of helium (He), nitrogen (N), or argon (Ar). The method of claim 4,
Graphene oxide lamination method, characterized in that the amount of the carbon source gas is provided at a rate of 10 sccm to 50 sccm. The method of claim 4,
In the step of laminating the graphene oxide,
Graphene oxide lamination method, characterized in that the separation distance between the substrate portion and the nozzle portion is set to 5 mm to 10 mm. The method of claim 4,
The step of laminating the graphene oxide,
The graphene oxide lamination method, characterized in that by controlling the intensity of the plasma discharged from the nozzle unit to control rotational drive of the substrate unit and a moving direction of the nozzle unit.

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