TW201825395A - Large-area graphene and manufacturing method thereof capable of obtaining graphene having a diameter value between 1 <mu>m and 50 <mu>m obtained by a Raman spectroscopy - Google Patents

Abstract

A manufacturing method of graphene comprises the following steps: providing a substrate and disposing a carbon source on the substrate, wherein the substrate is made of cobalt or nickel; placing the substrate in a heating furnace, wherein the heating furnace provides a heating temperature between 1000 DEG C and 1300 DEG C and an atmosphere environment for a predetermined period of time so as to allow the carbon source to permeate the substrate; and continuously cooling the heating furnace at a cooling rate between 0.1 DEG C/min and 5 DEG C/min so as to enable the carbon source permeating the substrate to be recrystallized for precipitating the graphene attached onto the substrate. The growth rate of the graphene is increased at a low cooling rate between 0.1 DEG C/min and 5 DEG C/min, and the graphene obtained after the process is finished has a diameter value (La) between 1 <mu>m and 50 <mu>m obtained by a Raman spectroscopy.

Description

Large-area graphene and manufacturing method thereof

The invention relates to a graphene and a manufacturing method thereof, and in particular to a large-area graphene and a manufacturing method thereof.

Currently, graphene is one of the thinnest and most robust nanomaterials in the world, and at the same time has excellent electrical conductivity, heat dissipation, light transmission and mechanical properties. Therefore, graphene has become The material of choice in the technical field, and in order to obtain graphene, various manufacturers use different separation techniques to delaminate the carbon layer of graphite.

For example, Chinese Patent Publication No. 102296361 proposes a method for preparing single crystal graphene. First, a solid hydrocarbon is set in a metal foil, and it is performed in a vacuum environment or a mixed atmosphere of hydrogen and an inert gas. A thermal decomposition treatment, and then lowering the temperature to room temperature in a vacuum environment or a mixed atmosphere of hydrogen and an inert gas to obtain a single crystal graphene on the outer surface of the metal foil; wherein the temperature of the thermal decomposition treatment is higher than that of the solid The decomposition temperature of the hydrocarbon is lower than and close to the melting temperature of the metal foil.

In the above prior art, the conventional method for making graphene by epitaxial growth is to cool down rapidly at a temperature lower than 50 ° C for one minute, and the faster the temperature decreases, the faster the graphene growth rate becomes. Slow, the area of the graphene obtained after the process temperature drops to room temperature is also relatively small. Therefore, the graphene produced by the traditional technology is not conducive to industrial application.

The main purpose of the present invention is to solve the problem that the area of the graphene produced by the conventional method is small.

To achieve the above object, the present invention provides a method for manufacturing graphene, including the following steps:

Providing a substrate and setting a carbon source on the substrate, and the material of the substrate includes cobalt or nickel;

Placing the substrate in a heating furnace that provides a heating temperature between 1000 ° C and 1300 ° C and an atmospheric environment and maintains the predetermined time for the carbon source to infiltrate the substrate; and

Continuously reducing the temperature of the heating furnace at a cooling rate between 0.1 ° C / minute and 5 ° C / minute, so that the carbon source infiltrated into the substrate is recrystallized to precipitate a graphene attached to the substrate;

The graphene has a diameter of La between 1 μm and 50 μm, and the La is a value obtained by Raman spectroscopy.

It can be known from the above that the effect that the present invention can achieve compared with the conventional technique is that the slow cooling rate between 0.1 ° C / min and 5 ° C / min is used to increase the growth rate of the graphene, and after the end of the manufacturing process The graphene was obtained, which has a diameter La between 1 μm and 50 μm obtained from a Raman spectrum.

The detailed description and technical contents of the present invention are described below with reference to the drawings:

Please refer to "Figure 1" for a flowchart of the steps for manufacturing graphene according to an embodiment of the present invention. The present invention is a method for manufacturing graphene, which includes the following steps:

Step S1: A substrate is provided and a carbon source with a weight percentage between 0.1 wt% and 10 wt% is provided on the substrate. The material of the substrate includes cobalt or nickel. In this embodiment, the carbon source may be Polyimide (PI), Graphite, Carbon Black, or a combination thereof.

Step S2: The substrate carrying the carbon source is placed in a heating furnace. The heating furnace provides a heating temperature between 1000 ° C and 1300 ° C and an atmospheric environment and maintains the carbon source for a predetermined time, so that the carbon source Infiltrated into the substrate, in this embodiment, the atmosphere environment may be a vacuum environment, a nitrogen environment, or an argon environment; the predetermined time is between 1.5 hours and 2.5 hours. In a preferred embodiment, the predetermined time is 2 hours, and the heating temperature is between 1220 ° C and 1290 ° C.

Step S3: The heating furnace is continuously cooled at a cooling rate between 0.1 ° C / minute and 5 ° C / minute, so that the carbon source infiltrated into the substrate is recrystallized to precipitate a graphene attached to the substrate. In this embodiment, the graphene has a diameter of La between 1 μm and 50 μm, and the La is a value obtained by Raman spectroscopy.

In an embodiment, the material of the substrate may be a mixture of copper with cobalt and nickel to form a cobalt-copper alloy and a nickel-copper alloy, or copper may be formed on the surface of the substrate, such as electroplating technology. Because copper cannot be dissolved with carbon, combining copper with the substrate in the above-mentioned manufacturing process of the graphene can reduce the rate of penetration of the carbon source into the substrate and the rate of recrystallization of the carbon source to precipitate the graphene. This arrangement can increase the area of the obtained graphene.

In the present invention, after the completion of step S3, the method further includes the following steps: step S4: after the temperature in the heating furnace is reduced to room temperature, the substrate is taken out of the heating furnace, and is attached to the substrate by a peeling process. The graphene on the substrate is separated from each other. The peeling process may be a mechanical peeling, an electrolytic peeling, or an acid etching peeling. The mechanical peeling is, for example, attached to the graphene surface layer with a low-viscosity adhesive tape and then tearing off. In order to separate the graphene from the substrate, the electrolytic stripping, for example, puts the substrate in an electrolytic solution and connects an anode and the electrolytic solution connects to a cathode to separate the graphene from the substrate, and the acid solution For example, the substrate is placed in a container containing an acidic solution, and a portion of the substrate in contact with the graphene is eroded by the acidic solution to separate the graphene from the substrate.

To sum up, since the present invention uses a slow cooling rate between 0.1 ° C / min to 5 ° C / min to increase the growth rate of the graphene, it is not customary to cool down rapidly at a cooling rate above 50 ° C per minute. Therefore, the graphene obtained after the end of the manufacturing process has a diameter La between 1 μm and 50 μm obtained from a Raman spectrum.

The present invention has been described in detail above, but the above is only a preferred embodiment of the present invention, and the scope of implementation of the present invention cannot be limited. That is, all equivalent changes and modifications made in accordance with the scope of the application of the present invention should still fall within the scope of the patent of the present invention.

Steps S1 ~ S4‧‧‧‧

[Fig. 1] is a flowchart of steps for manufacturing graphene in an embodiment of the present invention.

Claims (9)

A method for manufacturing large-area graphene includes the following steps: a substrate is provided and a carbon source is disposed on the substrate, and the material of the substrate includes cobalt or nickel; the substrate is placed in a heating furnace, and the heating furnace provides A heating temperature between 1000 ° C. and 1300 ° C. and an atmosphere environment for a predetermined time to allow the carbon source to penetrate the substrate; and the heating furnace at a temperature between 0.1 ° C./minute and 5 ° C./minute The cooling rate is continued to reduce the temperature, so that the carbon source infiltrated into the substrate is recrystallized to precipitate a graphene attached to the substrate; wherein the graphene has a diameter between La and 1 μm to 50 μm, and the La system is a Value obtained from Raman spectroscopy. The manufacturing method according to item 1 of the scope of patent application, wherein the carbon source is selected from the group consisting of a polyimide, a graphite, and a carbon black. The manufacturing method according to item 1 of the scope of the patent application, wherein the atmosphere environment is selected from the group consisting of a vacuum environment, a nitrogen environment, and an argon environment. The manufacturing method according to item 1 of the scope of patent application, wherein the predetermined time is between 1.5 hours and 2.5 hours. The manufacturing method according to item 1 of the scope of patent application, wherein the predetermined time is 2 hours. The manufacturing method according to item 1 of the scope of patent application, wherein a copper layer is formed on the surface of the substrate. The manufacturing method according to item 1 of the scope of patent application, wherein the material of the substrate is a cobalt copper alloy or a nickel copper alloy. The manufacturing method according to item 1 of the scope of patent application, wherein the graphene attached to the substrate is separated from each other by a peeling process, and the peeling process is selected from a mechanical peeling, an electrolytic peeling, and an acid etching A group of divestments. A large-area graphene is manufactured by a method according to any one of claims 1 to 8.