JP2020200210A - Method for manufacturing graphene bonded body consisting of aggregate of graphene formed by bonding overlapped flat surface of graphene and method for covering surface of graphene bonded body with metal or aggregate of insulating metal oxide fine particle - Google Patents

Abstract

To provide a method for manufacturing a graphene bonded body consisting of an aggregate of graphene formed by bonding the overlapped flat surfaces of graphene, and a method for covering the surface of the graphene bonded body with metal or an aggregate of insulating metal fine particles.SOLUTION: The method for manufacturing a graphene bonded body consisting of an aggregate of graphene formed by bonding the overlapped flat surfaces of graphene comprises: the first step of manufacturing the aggregate of graphene from an aggregate of graphite particles in methanol; the second step of separating the aggregate of graphene into graphene one by one in the methanol; the third step of repeatedly adding vibrations in the front and back, right and left, and top and bottom directions to a vessel; and the fourth step of equally compressing the upper surface of the aggregate of graphene to generate frictional heat in a portion having the overlapped flat surfaces to form a graphene bonded body obtained by bonding the flat surfaces of graphene by the frictional heat on the bottom surface of the vessel as the shape of the bottom surface.SELECTED DRAWING: Figure 1

Description

The present invention breaks the interlayer bond of the basal plane of graphite crystals forming graphite particles in a container filled with methanol to produce a group of graphene composed of the basal plane. Next, the flat surfaces on which the flat surfaces of graphene are overlapped are joined to each other, and a graphene junction composed of a collection of graphene is produced on the bottom surface of the container as the shape of the bottom surface. In addition, the surface of the graphene conjugate is covered with a collection of fine particles of metal or insulating metal oxide. Graphene is a single crystal material composed of a collection of carbon atoms that two-dimensionally forms a network structure in which carbon atoms are hexagonal, and has a thickness of 0.332 nm, and is an extremely lightweight material. Further, in the present invention, a group of thin film-like graphene in which the flat surfaces of graphene are directly overlapped and bonded is called a graphene junction. The graphite particles are the cheapest carbon materials composed of only single crystals of graphite and 100% of graphite is crystallized. When the interlayer bond between the basal planes of the graphite crystals forming the graphite particles is broken, the basal plane A collection of graphene consisting of is obtained.

In 2004, a physicist at the University of Manchester in the United Kingdom used cellophane tape to tear off a single crystallite from graphite, the basal plane, which two-dimensionally forms a network of hexagonal carbon atoms. For the first time, we succeeded in extracting a planar substance having a thickness of carbon atoms. This new substance was called graphene. The 2010 Nobel Prize in Physics has been awarded for this research result.

Graphene is an extremely thin substance whose thickness corresponds to the size of a carbon atom, and is a completely new carbon material having almost no mass. For this reason, it has physical properties that are far from those of conventional substances, and is attracting attention as a material that can be applied to a wide range of applications.
For example, it is the thinnest material with a thickness of 0.332 nm. It also has the largest surface area of 3000 m ² / g per unit mass. Further, it has a Young's modulus as large as 1020 GPa, and is the most stretchable and bendable material. Moreover, it is the toughest substance having a large shear modulus of 440 GPa. Further, the thermal conductivity is 19.5 W / Cm, which is 4.5 times the thermal conductivity of silver, which has the highest thermal conductivity among metals. Moreover, the current density exceeds 1000 times that of copper. Furthermore, it has electrical conductivity that is only 23 times the specific resistance of copper. Further, the electron mobility is 15000 cm ² / volt / sec, which is an order of magnitude higher than the mobility of silicone of 1400 cm ² / volt / sec. Further, it is a single crystal material having a melting point of more than 3000 ° C. and has extremely high heat resistance.

Graphene, on the other hand, is produced in a variety of ways. For example, the professor at Manchenster University mentioned above physically peeled graphene from graphite by hand. In this method, it is difficult to peel off a large amount of graphene in a short time, and the peeled material is not always a single layer of graphite crystals, that is, graphene.
Further, Patent Document 1 describes a method for producing graphene by thermally decomposing a single crystal of silicon carbide. That is, the silicon carbide is heated in an inert atmosphere to thermally decompose the surface. At this time, silicon having a relatively low sublimation temperature is preferentially sublimated, and graphene is produced by the remaining carbon. However, a single crystal of silicon carbide is an expensive material. Furthermore, in order to produce graphene having a large area, a single crystal of silicon carbide must be grown, which makes the single crystal of silicon carbide even more expensive. Further, silicon is sublimated at a high temperature exceeding 1600 ° C. and in an atmosphere having a high degree of vacuum, but if even a small amount of silicon remains, graphene is not produced as a residue after thermal decomposition. Therefore, the cost of producing a single crystal of carbonized silica and the thermal decomposition treatment of the single crystal becomes very expensive. In addition, producing a large amount of graphene is more expensive.
Further, Patent Document 2 describes a method for producing graphene by bringing a carbon-based substance into contact with a sheet-shaped single crystal graphitized metal catalyst and heat-treating it in a reducing atmosphere. However, this manufacturing method is also not an inexpensive manufacturing method and is not a manufacturing method having excellent mass productivity. First, the production cost of producing a single crystal graphitized metal catalyst is even higher than that of a single crystal of silicon carbide. Second, the method of contacting a single crystal graphitized metal catalyst with a carbon-based substance is inferior in mass productivity. Thirdly, the method of reducing the graphitized metal catalyst in an atmosphere rich in nitrogen gas including hydrogen gas at a high temperature exceeding 1000 ° C. becomes expensive. Therefore, producing a large amount of graphene is more expensive.

None of the graphene production methods to date have been, first of all, a method of simultaneously producing a large amount of graphene by an inexpensive production method. Second, the graphene produced is not necessarily graphene. In other words, graphene is a single crystal material consisting of a collection of carbon atoms that two-dimensionally forms a network structure in which carbon atoms are hexagonal, and if carbon atoms cannot grow in crystals in an atmosphere free of impurities, Graphene is not produced. Furthermore, since the graphene produced is extremely thin and extremely lightweight, it is difficult to confirm that it is graphene.
Therefore, the present inventor has found a method in which all the graphene produced is a complete graphene and a large amount of graphene is instantly produced by an extremely simple method (Patent Document 3). That is, it consists of only a single crystal of graphite, the crystallization of graphite progresses 100%, and a mass of natural graphite crystal, which is the cheapest carbon material, is crushed, and scaly graphite particles or scaly graphite particles or scaly graphite crystals are crushed from the crushed graphite crystal. A collection of aggregated graphite particles is selected. The collection of graphite particles is narrowed into the gap between the two parallel plate electrodes, an electric field is applied to the two parallel plate electrodes, and the application of the electric field forms graphite particles. This is a method for producing a large amount of graphene composed of the basal plane by simultaneously breaking the interlayer bond of the basal plane of the graphite crystal. According to this production method, a collection of 1.62 × 10 ¹³ graphenes can be instantly obtained from only 1 g of scaly graphite particles or lump graphite particles.

JP-A-2015-110485 JP-A-2009-143799 Patent No. 6166860

As explained in paragraph 3, graphene has amazing physical properties that are completely different from conventional materials, so research and development of various parts and devices using graphene are being carried out. Therefore, if a method for producing a graphene conjugate composed of a collection of graphene obtained by joining the flat surfaces in which the flat surfaces of graphene overlap each other can be found from a collection of graphene produced by an inexpensive production method, the properties of graphene can be found. Inexpensive parts and devices using graphene joints close to the above will be put into practical use. Furthermore, if the surface of the graphene joint can be covered with a collection of fine particles of metal or insulating metal oxide, the graphene joint having a conductive or insulating surface can be pressure-bonded to the base material or parts. The properties of a graphene joint can be imparted to the base material and parts.
On the other hand, a large amount of graphene can be instantly produced by the production method according to Patent Document 3, but a method for producing a graphene conjugate has not been found from this collection of graphene. Graphene is an extremely thin substance, extremely lightweight, and has almost no mass. Furthermore, the area of graphene produced from graphite particles is small and difficult to handle. Further, graphene produced by simultaneously breaking the interlayer bond of graphite crystals in graphite particles by applying an electric field in Patent Document 3 is easily scattered during and after production. Further, since graphene is extremely thin, it has a flat surface having an extremely large aspect ratio, which is the ratio of the size of the crystal plane to the thickness. Further, since the graphite particles have a constant shape and the shapes of the graphite particles are not the same, the aspect ratio of the graphene produced by breaking the interlayer bond of the graphite crystals in the graphite particles is different for each graphene. Therefore, in the production method in Patent Document 3, graphene flat surfaces easily overlap each other when graphene is produced. Moreover, the number of overlapping graphenes is not constant. In addition, it is difficult to distinguish whether or not the flat surfaces overlap each other, and there is a method of distinguishing by observing with an electron microscope. Further, since the graphenes overlapping on the flat surfaces have a weak bonding force on the flat surfaces, the graphene joints are easily separated at the sites where the flat surfaces overlap. For this reason, a graphene junction cannot be formed unless the flat surfaces on which the flat surfaces of graphene overlap each other are firmly bonded to each other.
Therefore, there are the following five problems to be solved in manufacturing a graphene junction composed of a collection of graphene obtained by joining the flat surfaces in which the flat surfaces of graphene are overlapped with each other.
First, a collection of graphene is produced in a container filled with a liquid with low viscosity and low boiling point. As a result, the graphene precipitated in the liquid does not scatter during and after the production of graphene.
Second, a flat surface of graphene is superposed on the bottom surface of the container via a liquid. Further, the temperature of the container is raised to the boiling point of the liquid, the liquid is vaporized, and a collection of graphene on which flat surfaces are overlapped is formed on the bottom surface of the container. That is, the thickness of graphene is extremely thin, and the aspect ratio, which is the ratio of the surface area to the thickness, is extremely large. In addition, graphene is extremely thin and has almost no mass. Therefore, a group of graphene with overlapping flat surfaces can be formed on the bottom surface of the container by a method utilizing these two characteristics.
Third, the plane above the graphene cluster is evenly compressed, frictional heat is generated at the site where the graphene flat planes overlap, and the overlapping flat planes are joined by the frictional heat, and the graphene junction is formed into a container. It is formed as the shape of the bottom surface on the bottom surface of That is, graphene is a tough material having a breaking strength of 42 N / m, which is more than 100 times stronger than steel. Therefore, by a method utilizing this feature, the portions where the flat surfaces overlap can be firmly joined.
Fourth, the treatments in the above three steps are all extremely simple treatments, and the materials used are general-purpose and inexpensive materials. Thereby, the graphene aggregate is produced by an inexpensive method and the graphene conjugate is produced by an inexpensive method using an inexpensive graphite particle aggregate. As a result, a graphene conjugate having properties similar to those of graphene can be produced at low cost.
In manufacturing a graphene conjugate, the problems to be solved are the above four problems.
Further, there are the following three problems to be solved when covering the surface of the graphene bonded body with a collection of fine particles of a metal or an insulating metal oxide.
First, the surface of the graphene junction formed on the bottom surface of the container in the shape of the bottom surface is covered with a collection of fine particles made of a metal or an insulating metal oxide. Therefore, it is necessary that the raw material of the metal or the insulating metal oxide is liquid-phased.
Second, a graphene conjugate whose surface is covered with a collection of fine particles of metal or insulating metal oxide can be removed from the container. As a result, the graphene joint having a conductive or insulating surface can be pressure-bonded to the base material or the component, and the properties of the graphene joint can be imparted to the base material or the component.
Thirdly, it is extremely easy to cover the surface of the graphene joint with a collection of fine particles made of metal or an insulating metal oxide, and the material used is a general-purpose and inexpensive material. As a result, an inexpensive graphene joint can be pressure-bonded to a base material or a component.
In covering the surface of the graphene joint with a collection of fine particles made of a metal or an insulating metal oxide, the problems to be solved are the above three problems.
Therefore, there are a total of seven problems to be solved by the present invention.

A method for producing a graphene junction composed of a collection of graphene obtained by joining the flat planes in which the flat planes of graphene overlap each other is
A collection of scaly graphite particles or a collection of massive graphite particles is flatly packed on the surface of one of the two parallel plate electrodes, and the parallel plate electrode is immersed in methanol filled in a container. Further, the other parallel plate electrode is superposed on the one parallel plate electrode, and the two parallel plate electrodes are separated from each other through a collection of the scaly graphite particles or a collection of the massive graphite particles. At the same time, the two separated parallel plate electrodes are immersed in the graphite, and then a DC potential difference is applied to the gap between the two parallel plate electrodes, whereby the magnitude of the potential difference is increased. An electric field corresponding to the value divided by the size of the gap between the two parallel plate electrodes is applied to the aggregate of the scaly graphite particles or the aggregate of the lump graphite particles, and the application of the electric field causes the scaly graphite particles. Or, all of the interlayer bonds of the basal plane forming the massive graphite particles are simultaneously destroyed, and a group of graphene corresponding to the basal plane is produced in the gap between the two parallel plate electrodes. The gap between the two parallel plate electrodes is expanded, the two parallel plate electrodes are tilted in the methanol, and vibrations in three directions of left and right, front and back, and up and down are repeatedly applied to the container to form a collection of graphene. , The two parallel plate electrodes are moved into the methanol through the gap between the two parallel plate electrodes, and then the two parallel plate electrodes are taken out from the container, and the container is vibrated in three directions of front-back, left-right, and up-down. Repeatedly added, a collection of graphene in which the flat planes of the graphene are overlapped with each other via methanol is formed on the bottom surface of the container in the shape of the bottom surface, after which the container is heated to the boiling point of the graphite. Methanol is vaporized to form an aggregate of the graphene on which the flat planes of the graphene are overlapped on the bottom surface of the container as the shape of the bottom surface, and then the plane above the aggregate of graphene is evenly compressed. Friction heat is generated at the site where the graphite flat surfaces overlap, and the frictional heat joins the graphite flat surfaces that overlap each other, and joins the graphite flat surfaces that overlap each other. A graphene junction composed of a collection of graphite formed is formed on the bottom surface of the container as the shape of the bottom surface. The graphene junction composed of a collection of graphite obtained by joining the graphite flat surfaces on which the graphite flat surfaces overlap each other. Is a method of manufacturing.

A method for producing a graphene junction composed of a collection of graphene obtained by joining the flat surfaces on which the flat surfaces of graphene overlap each other comprises the following four steps.
First, graphene aggregates are produced from graphite particle aggregates in methanol. That is, a collection of scaly graphite particles or a collection of massive graphite particles narrowed in the gap between the two parallel plate electrodes is immersed in methanol, which is an insulator, and a DC potential difference between the two parallel plate electrodes. Is applied. As a result, an electric field corresponding to the value obtained by dividing the potential difference by the size of the gap between the two parallel plate electrodes is generated in the electrode gap where a collection of scaly graphite particles or a collection of massive graphite particles exists. This electric field simultaneously applies a Coulomb force sufficient for breaking the interlayer bond of the basal plane made of graphite crystals to all the above-mentioned graphite particles to all the π electrons that are responsible for the interlayer bond of the basal plane. As a result, the π electron is released from the constraint on the π orbital, and all the π electrons are separated from the π orbital and become free electrons. That is, when the Coulomb force acting on the π electron is given to the π electron as a force larger than the interaction of the π orbitals, the π electron is released from the constraint of the π orbital and becomes a free electron. As a result, all the π electrons that are responsible for the interlayer bonding of the basal plane do not exist in the π orbital, and for all the graphite particles, all of the interlayer bonding of the basal plane made of graphite crystals forming the graphite particles are simultaneously performed. It will be destroyed. As a result, a collection of basal planes, that is, a collection of graphene, is instantly produced in the gap between the two parallel plate electrodes. The graphene produced is an intrinsic substance consisting only of graphite crystals without impurities. Since the two parallel plate electrodes are immersed in methanol, the graphene deposited in the gap between the two parallel plate electrodes does not scatter. As a result, the first problem out of the four problems in producing the graphene conjugate described in paragraph 7 was solved.
When a potential difference is applied between two parallel plate electrodes immersed in methanol, which is an insulator, an electric field is generated in the gap between the two parallel plate electrodes. That is, methanol is an insulator having a specific resistance of 3 megaΩ · cm or more and a dielectric constant of 33. Ethanol is also an insulator having a dielectric constant of 24. The electric conductivity of ethanol is 7.5 × ^10-6 S / m, and the electric conductivity of the scaly graphite particles is 43.9 S / m. Thus, ethanol, compared to the scaly graphite particles is a conductor, the electric conductivity is 1.7 × 10 ⁷ times lower insulator.
Second, a collection of graphene is moved into methanol through the gap between the two parallel plate electrodes. Therefore, the gap between the two parallel plate electrodes is expanded in methanol, further inclined in methanol, and then vibrations in three directions are applied to the container filled with methanol. As a result, the graphene aggregate moves into the methanol through the gap between the two parallel plate electrodes. After that, the two parallel plate electrodes are taken out from the container.
Thirdly, vibrations in three directions of front-back, left-right, and up-down are repeatedly applied to the container to form a group of graphene in which the flat surfaces of graphene are overlapped with each other via methanol as the shape of the bottom surface of the container. In other words, the aspect ratio of graphene is extremely large and it is extremely lightweight, so when the container is vibrated in three directions, graphene moves in methanol with the flat surface facing up, and graphene diffuses over the entire bottom surface of the container. At the same time, the flat planes overlap each other via methanol. On the other hand, when a collection of graphene is deposited in the gap between the two parallel plate electrodes, a part of graphene overlaps with each other on the flat surfaces. Vibration of methanol is applied to the graphene joint surfaces on which these flat surfaces overlap to separate the graphene joint surfaces. Therefore, as for the vibration acceleration applied to the container, in order to separate the graphene on which the flat surfaces overlap, the vibration acceleration of about 0.5 G is first applied, and then the vibration acceleration of about 0.2 G is applied to put the graphene in methanol. Move with. After that, when the vibration to the container is stopped, a collection of graphene in which the flat surfaces are overlapped with each other via methanol is formed on the bottom surface of the container as the shape of the bottom surface. Further, when the temperature of the container is raised to the boiling point of methanol and the methanol is vaporized, a collection of graphene in which flat surfaces are overlapped is formed on the bottom surface of the container as the shape of the bottom surface. As a result, the second problem out of the four problems in producing the graphene conjugate described in paragraph 7 was solved.
In the next fourth step, since the graphene joints are formed by joining the flat planes on which the flat planes overlap each other, it is not necessary to separate all the graphene into individual graphenes. , A collection of graphene with a large number of overlapping graphenes is separated by vibration of methanol. In addition, the vaporized methanol is recovered by a recovery machine and reused.
Fourth, the plane above the group of graphene formed on the bottom surface of the container is evenly compressed, frictional heat is generated at the portion where the flat planes of graphene overlap each other, and the flat planes of graphene are separated by the frictional heat. A graphene junction composed of a collection of graphene obtained by joining the graphene flat surfaces on which the flat planes of the graphene are overlapped is formed on the bottom surface of the container as the shape of the bottom surface. That is, graphene has a breaking strength of 42 N / m, which is more than 100 times that of steel. Therefore, even if an excessive compressive stress is applied to the plane above the group of graphene formed on the bottom surface of the container, the flat plane of graphene is neither deformed nor broken. Therefore, evenly compressing the plane above the graphene cluster formed on the bottom of the container does not reduce the applied compressive stress, but applies compressive stress to the overlapping flat planes of the graphene. , Friction heat is generated at the part where the flat surfaces overlap each other, and the graphene flat surfaces are joined to each other by the frictional heat, and the graphene composed of a group of graphenes formed by joining the flat surfaces where the flat surfaces of graphene overlap each other. A joint is formed on the bottom surface of the container in the shape of the bottom surface. Since graphene was precipitated in methanol and the treatment in methanol was continued, graphene is a genuine substance consisting only of graphite crystals without impurities. Since the flat surfaces of graphene are joined by frictional heat, the flat surfaces of graphene are firmly joined. As a result, the third problem out of the four problems in producing the graphene conjugate described in paragraph 7 was solved.
In the graphene junction, since the flat surfaces of graphene are bonded by frictional heat, the graphene is bonded with a constant bonding force. Therefore, when vibrations in three directions of left-right, front-back, and up-down are applied to the container in which the graphene joint is formed on the bottom surface of the container for a short time, the graphene joint dissociates from the container and the graphene joint is released from the container. Can be taken out. In addition, the graphene joint taken out can be handled. The vibration acceleration applied to the container is about 0.2 G because the graphene joint is extremely lightweight.
By the way, methanol used in producing a graphene conjugate is an inexpensive industrial chemical. Graphite particles are also an inexpensive industrial material. In addition, the above-mentioned four steps consist of extremely simple processes. Therefore, according to this method, when four extremely simple steps are carried out in succession using inexpensive graphite particles and methanol, the graphene obtained by joining the graphenes in which the graphenes are overlapped with each other. A graphene junction composed of aggregates is formed on the bottom surface of the container in the shape of the bottom surface. As a result, the fourth problem out of the four problems in producing the graphene conjugate described in paragraph 7 was solved, and all the problems were solved.
The graphene conjugate produced by the production method described above brings about the following effects.
First, graphene has a thickness of 0.332 nm, which corresponds to the size of a carbon atom, is extremely lightweight, and has almost no mass. Moreover, since the thickness is extremely thin, the presence of graphene cannot be visually confirmed. Moreover, the area of graphene produced from graphite particles is small. Therefore, it is difficult to handle graphene one by one. On the other hand, the graphene joints in which graphenes are joined to each other via a flat surface are thin, but have a certain area, so that each graphene joint can be handled. Since this graphene conjugate is composed only of graphene, it is close to the properties of graphene. Further, the graphene conjugate is an inexpensive industrial material that can be manufactured by an inexpensive method using an inexpensive material. For this reason, application to various industrial products using graphene conjugates will be pioneered.
Secondly, a graphene joint having the shape of the bottom surface is manufactured on the bottom surface of the container. Therefore, a graphene joint having a thickness of submicron can be produced, and the shape and area of the graphene joint can be freely changed according to the shape of the bottom surface of the container. For this reason, graphene conjugates with excellent both thermal and electrical conductivity can be of any size, shape, and thickness, including electrodes and contacts with small areas, elongated wiring patterns, and heat conductive sheets with large areas. It can be freely manufactured as a graphene conjugate having the properties of graphene.
Third, the graphene conjugate is excellent in both thermal conductivity and electrical conductivity. That is, as described above, graphene has both thermal conductivity equivalent to 4.5 times the thermal conductivity of silver and electrical conductivity corresponding to only 23 times the specific resistance of copper. Therefore, the graphene junction in which the flat surfaces of graphene are joined has properties similar to those of graphene, and has both thermal conductivity and electrical conductivity, as well as an antistatic function, an electromagnetic wave shielding function, and a heat dissipation function.
Fourth, in the graphene junction, graphenes, which are genuine substances consisting only of graphite crystals without impurities, are bonded to each other by frictional heat via a flat surface, so that the graphenes are firmly bonded to each other. Further, the gap at which graphenes are joined is narrower than 0.332 nm, which corresponds to the thickness of graphene. Therefore, the substance cannot enter the gap between graphenes. Further, the graphene conjugate is composed only of graphene having a melting point of more than 3000 ° C., and has heat resistance close to that of graphene. Graphene is an extremely stable substance that is not eroded by acids or alkalis. Therefore, the graphene conjugate does not change over time no matter what environment it is used in. Therefore, graphene conjugates having graphene properties are used as industrial materials in various fields.
Fifth, the surface irregularities of the graphene joint are only 0.332 nm of the graphene thickness, which is close to a perfect flat surface. Therefore, the surface of the graphene bonded body exhibits super water repellency with a contact angle close to 180 degrees, and the surface is provided with water repellency, oil repellency, and antifouling property.
Here, in the first treatment, the interlayer bond of the basal plane made of graphite crystals forming graphite particles narrowed in the gaps between the two parallel plate electrodes by the electric field applied to the gaps between the two parallel plate electrodes. However, the phenomenon of being destroyed at the same time will be explained.
The carbon atom forming the graphite crystal in the graphite particles has four valence electrons. Three of these valence electrons are the basal plane, that is, the σ electrons that form graphene. These σ electrons covalently bond with the σ electrons of three adjacent carbon atoms on the basal plane at an angle of 120 degrees to form a strong hexagonal network structure two-dimensionally. The remaining one valence electron is a π electron, which exists in a π orbit extending in a direction perpendicular to the basal plane. The π-electrons are bonded to the π-electrons of adjacent carbon atoms in the vertical direction perpendicular to the basal plane with a weak bonding force, and the basal plane is laminated in layers based on this weak bonding force. That is, the basal plane, that is, graphene, is layered to each other by the interaction of π orbitals, which is a weak bonding force. Therefore, the graphite particles have a property of being easily peeled off at the basal plane made of graphite crystals, that is, having mechanical anisotropy. This mechanical anisotropy is well known as the lubricity of graphite particles.
When an electric field is applied to these graphite particles, a Coulomb force due to the electric field acts on all π electrons. When the Coulomb force acting on the π electron acts on the π electron as a force larger than the interaction of the π orbital acting on the π electron, the π electron is released from the constraint on the π orbit. As a result, all π electrons move away from the π orbital and become free electrons. As a result, all the π electrons that are responsible for the interlayer bonding of the basal plane disappear from the π orbital, so that all the interlayer bonding of the basal plane is destroyed at the same time. That is, when the π electron moves a distance of the interlayer distance b of the basal plane by the Coulomb force F, the π electron performs work W (W = b · F). This work W is 35 millielectronvolts, which is the magnitude of the interaction of π orbitals per atom acting on π electrons (electron volt is a unit that expresses the magnitude of energy possessed by an electron, and 1 electron volt is 1. ^Beyond (corresponding to 62 × ^10-19 joules), the π electron is released from the constraint of the interaction of the π orbit and becomes a free electron. For example, if the gap between the two parallel plate electrodes is separated by 100 μm and a DC potential difference of 10.6 kilovolt or more is applied to the gap between the electrodes, the interlayer bond on the basal plane is instantly broken. As described above, a large amount of graphene can be inexpensively produced by an extremely simple means of applying an electric field to a collection of inexpensive graphite particles. Further, since all the interlayer bonds of the basal plane are broken at the same time, the obtained fine substance is graphene, which is the basal plane made of graphite crystals.
The group of graphite particles referred to here means a group of relatively small amounts of graphite particles of about 1 g to 100 g. That is, the scaly graphite particles or the massive graphite particles are fine particles having a bulk density of 0.2-0.5 g / cm ³ and a particle size of 1-300 microns. Therefore, it is easy to pull the aggregate of graphite particles into the gap between the two parallel plate electrodes, and it is also easy to apply a potential difference to the two parallel plate electrodes. When a potential difference is applied to the gap between the two parallel plate electrodes, an electric field is generated in all the regions where the graphite particles are attracted. This electric field acts on the π electron as a Coulomb force larger than the interaction of the π orbit, and the π electron is released from the constraint on the π orbit and becomes a free electron. As a result, all the interlayer bonds of the basal plane in the graphite particles are simultaneously broken, and a graphene aggregate is produced in the gap between the two parallel plate electrodes.
Here, the number of graphene dispersed in the suspension is calculated by arithmetic. Here, it is assumed that all graphite particles are composed of spheres having a diameter of 25 microns, and since the true density of graphite is 2.25 × 10 ³ kg / m ³ , the weight of one graphite particle is high. Is only 1.84 x ^10-8 g. Assuming that the average thickness of the graphite particles is 10 microns, the interlayer distance is 3.354 angstroms. Therefore, 297,265 graphenes are laminated on the scaly graphite particles having a thickness of 10 microns. .. Therefore, by breaking all the interlayer bonds on the basal plane, a collection of 297,265 graphenes can be obtained from only one spherical graphite particle. Therefore, for an aggregate of only 1 g of spherical graphite particles, an aggregate of 1.62 × 10 ¹³ graphenes can be obtained when all the interlayer bonds on the basal plane are broken. Therefore, according to this production method, an enormous number of graphene aggregates can be obtained from a small amount of graphite particles.

The method of covering the surface of the graphene joint produced by the method described in paragraph 8 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum is a method.
A metal compound in which any of silver, copper, gold, or aluminum is thermally decomposed is dispersed in methanol to prepare a methanol dispersion, and the methanol dispersion is prepared by the method described in paragraph 8. The container in which the bonded body is formed on the bottom surface of the container is filled, and further, vibrations in three directions of left and right, front and back, and up and down are repeatedly applied to the container to bring the surface of the graphene bonded body into contact with the methanol dispersion. After that, the temperature of the container is raised to a temperature at which the metal compound is thermally decomposed, whereby the methanol is first vaporized, and a collection of fine crystals of the metal compound is simultaneously gathered on the surface of the graphene bond. After precipitation, fine crystals of the metal compound are thermally decomposed, and a collection of granular metal fine particles made of any metal of silver, copper, gold, or aluminum is simultaneously gathered on the surface of the graphene bond. Precipitated and metal-bonded at the site where the metal fine particles come into contact with each other, and the surface of the graphene joint is covered with a collection of metal fine particles made of any of the metal-bonded silver, copper, gold, or aluminum. This is a method of covering the surface of a graphene bond produced by the method described in paragraph 8 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum.

That is, when the temperature of the container filled with the graphene conjugate and the methanol dispersion of the metal compound is raised to a temperature at which the metal compound is thermally decomposed, methanol is first vaporized, and the surface of the graphene conjugate has fine metal compounds. A collection of fine crystals precipitates all at once, and a collection of fine crystals covers the graphene conjugate. That is, in the methanol dispersion of a metal compound, the metal compound is dispersed in methanol in a molecular state. Therefore, when methanol is vaporized from the methanol dispersion, a collection of fine crystals of the metal compound is formed on the surface of the graphene conjugate. It precipitates all at once and covers the surface of the graphene conjugate. The size of the fine crystals is close to the size of the precipitated fine particles. Next, when the temperature at which the metal compound begins to thermally decompose is reached, the metal compound decomposes into an inorganic substance or an organic substance and a metal. Since the density of the inorganic or organic matter is lower than the density of the metal, the inorganic or organic matter is deposited in the upper layer and the metal is deposited in the lower layer, and the inorganic or organic matter in the upper layer takes away the heat of vaporization and vaporizes, and immediately after the vaporization is completed, 40- A collection of granular metal fine particles made of any metal of silver, copper, gold, or aluminum having a size of 60 nm is deposited all at once on the surface of the graphene joint, covering the surface of the graphene joint. Since these metal fine particles have no impurities and are in an active state, they form metal bonds at sites where they come into contact with each other. Therefore, a collection of metal fine particles deposited on the surface of the graphene junction is metal-bonded at a site where they come into contact with each other, and the aggregate of the metal-bonded metal fine particles covers the surface of the graphene junction. As the amount of the metal compound dispersed in methanol increases, the amount of metal fine particles precipitated increases, and as a result, the amount of metal fine particles precipitated on the surface of the graphene conjugate increases, and a collection of metal-bonded metal fine particles is laminated and laminated. A collection of fine metal particles covers the surface of the graphene junction. As a result, the first of the three problems in covering the surface of the graphene joint described in paragraph 7 with a collection of metal fine particles was solved. The thermal conductivity and electrical conductivity of metal are superior in the order of silver, copper, gold, and aluminum. Further, all of these metals are soft metals having low hardness.
On the other hand, since the entire surface of the graphene junction is covered with a collection of metal-bonded metal fine particles, the collection of metal-bonded metal fine particles covers the graphene junction with a constant bonding force. Further, since the graphenes are bonded to each other by frictional heat via the flat surface of the graphene, the graphene joint also has a constant bonding force. Therefore, when the graphene joint is taken out from the container, if vibrations in three directions of front-back, left-right, and up-down are applied to the container for a short time, the graphene joint is dissociated from the container and the graphene joint can be taken out from the container. In addition, the graphene joint taken out can be handled. The vibration acceleration applied to the container is about 0.2 G because the graphene joint is extremely lightweight.
As a result, the second problem out of the three problems when covering the surface of the graphene joint described in paragraph 7 with a collection of metal fine particles was solved.
The graphene conjugate produced by the production method described above brings about the following effects.
First, a graphene joint having the shape of the bottom surface is manufactured on the bottom surface of the container. Therefore, a graphene joint having a thickness of submicron can be manufactured, and the shape and area of the graphene joint can be freely changed according to the shape of the bottom surface of the container. For this reason, graphene conjugates with excellent both thermal and electrical conductivity can be of any size, shape, and thickness, including electrodes and contacts with small areas, elongated wiring patterns, and heat conductive sheets with large areas. It can be freely manufactured as a graphene joint to have.
Second, graphene conjugates are excellent in both thermal and electrical conductivity. That is, as described above, graphene has both thermal conductivity equivalent to 4.5 times the thermal conductivity of silver and electrical conductivity corresponding to only 23 times the specific resistance of copper. Therefore, a graphene junction covered with a collection of fine metal particles made of any of silver, copper, gold, or aluminum has a relatively high thermal conductivity, that is, a flat surface of graphene that easily conducts heat. Heat is transferred preferentially, and the electric conductivity is relatively high, that is, the current flows preferentially to the collection of metal fine particles through which the current easily flows. As a result, the graphene conjugate has better thermal conductivity than silver and has conductivity close to that of metal. The specific resistance of aluminum is 1.6 times that of copper, and aluminum has a higher conductivity than graphene.
Third, the entire surface of the graphene joint is covered with a collection of metal fine particles made of soft metal of 40-60 nm, the surface has a surface roughness that is an order of magnitude smaller than that of mirror polishing, and the surface is water repellent and stain resistant. , Has lubricity properties.
Fourth, since the two planes of the graphene joint are covered with a collection of metal fine particles, the graphene joint can be crimped to the component or the base material. In other words, the metal composed of silver, copper, gold, and aluminum, which has excellent both thermal conductivity and electrical conductivity, is a soft metal with low hardness, and when compressive stress is applied to one plane of the graphene joint, this is applied. A collection of metal fine particles formed on a flat surface is plastically or elastically deformed to the surface of a part or a base material to bite or press contact, and the graphene joint presses against the part or the base material. Therefore, the graphene joint can be integrated with the component or the base material by crimping, and both the properties of thermal conductivity and electric conductivity can be imparted to the component and the base material.
Fifth, metal compounds that thermally decompose any of the metals silver, copper, gold, or aluminum are general-purpose industrial chemicals, and with extremely simple treatment, the surface of the graphene conjugate is silver. Covered with a collection of fine metal particles consisting of any metal, copper, gold, or aluminum. Therefore, using inexpensive materials and at low cost, the flat surfaces of graphene of arbitrary size, shape and thickness are covered with a collection of metal fine particles made of any metal such as silver, copper, gold or aluminum. The broken graphene conjugate can be optionally manufactured on the bottom surface of the container.
As a result, of the three problems in covering the surface of the graphene joint described in paragraph 7 with a collection of metal fine particles, the third problem was solved, and all the problems were solved.

The method of covering the surface of the graphene joint described in paragraph 10 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum is
A metal complex composed of an inorganic metal compound having a metal complex ion in which a ligand composed of an inorganic ion or a molecule is coordinated to a metal ion composed of a metal of silver, copper, gold, or aluminum. Used as a metal compound in which any of silver, copper, gold, or aluminum is precipitated by the thermal decomposition described in Paragraph 10, and the surface of the graphene conjugate is coated with silver, copper, gold, or aluminum according to the method described in paragraph 10. It is a method of covering with a collection of metal fine particles made of any of the above metals.

That is, when a metal complex composed of an inorganic metal compound having a metal complex ion in which a ligand composed of an inorganic ion or a molecule is coordinated to a metal ion is heat-treated in a reducing atmosphere, a metal is precipitated at 180-220 ° C. .. That is, when the metal complex composed of the inorganic metal compound is heat-treated in a reducing atmosphere, it is decomposed into an inorganic substance and a metal, the inorganic substance takes away heat of vaporization and vaporizes, and the vaporization of the inorganic substance is completed at 180-220 ° C., and the metal precipitates. And finish the thermal decomposition reaction.
That is, among the ions constituting the metal complex, the metal ion located in the center of the molecule is the largest, and the distance between the metal ion and the ligand is the longest. When this metal complex is heat-treated in a reducing atmosphere, the coordination bond portion where the metal ion binds to the ligand is first separated and decomposed into a metal and an inorganic substance. When the temperature rises further, the inorganic substance takes away the heat of vaporization and vaporizes, and when the vaporization of the inorganic substance is completed, the metal precipitates. Since the metal complex composed of such an inorganic metal compound has a small molecular weight, the vaporization of the inorganic substance is completed at 180-220 ° C., and the temperature at which the metal is precipitated is the lowest among the temperatures at which the metal is precipitated by the thermal decomposition of the metal compound. ..
Further, a metal complex ion in which a molecule or an ion composed of an inorganic substance serves as a ligand and is coordinate-bonded to the metal ion is easier to synthesize than other metal complex ions. As such metal complex ions, ammonia NH ₃ serves as a ligand to coordinate bond to metal ions, and water H ₂ O serves as a ligand to coordinate bond to metal ions. Hydroxometal complex ion, chlorine ion Cl ^{−, which} is coordinated to metal ion with complex ion, hydroxyl group OH ^― as a ligand, or chlorine ion Cl ⁻ and ammonia NH ₃ serve as ligand for metal ion. There are chlorometal complex ions that are coordinated to. All of these ligands have a small molecular weight. Further, a metal complex composed of an inorganic salt such as a chloride, a sulfate or a nitrate having such a metal complex ion has a small molecular weight of the inorganic salt. Therefore, the vaporization of the inorganic substance is completed in the temperature range of 180-220 ° C., and the metal is precipitated. The temperature at which this metal precipitates is the lowest among the temperatures at which the metal is precipitated by the thermal decomposition of the metal compound.
Therefore, the method of covering the surface of the graphene junction described in paragraph 10 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum is thermally decomposed into silver, copper, gold, or aluminum. As a metal compound that precipitates any metal, a ligand composed of an inorganic ion or molecule is composed of an inorganic metal compound coordinated to a metal ion composed of any metal of silver, copper, gold, or aluminum. Using a metal complex, the surface of the graphene conjugate is coated with silver, according to the method described in paragraph 10 in which the surface of the graphene conjugate is covered with a collection of metal fine particles made of any of silver, copper, gold, or aluminum. It is a method of covering with a collection of metal fine particles made of any metal such as copper, gold, or aluminum.

The method of covering the surface of the graphene joint described in paragraph 10 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum is
The first feature that the oxygen ion constituting the carboxyl group of the carboxylic acid is covalently bonded to the metal ion made of any metal of silver, copper, gold or aluminum, and the second feature that the carboxylic acid is made of a saturated fatty acid. A metal carboxylate compound having both characteristics is used as a metal compound in which any metal of silver, copper, gold, or aluminum is precipitated by the thermal decomposition described in paragraph 10, and graphene bonding is performed according to the method described in paragraph 10. It is a method of covering the surface of a body with a collection of metal fine particles made of any metal such as silver, copper, gold, or aluminum.

That is, the metal ion is the most common carboxylic acid metal compound having both the first characteristic that the oxygen ion constituting the carboxyl group of the carboxylic acid is covalently bonded to the metal ion and the second characteristic that the carboxylic acid is composed of a saturated fatty acid. It is a large ion, and the distance between the oxygen ion constituting the carboxyl group and the metal ion is longer than the distance between other ions. When a metal carboxylic acid compound having such molecular structural characteristics is heat-treated in an air atmosphere, when the boiling point of the carboxylic acid is exceeded, the bond portion between the oxygen ion and the metal ion constituting the carboxyl group is first separated, and the carboxylic acid. And metal. When a carboxylic acid is composed of a saturated fatty acid, it does not have an unsaturated structure in which carbon atoms are excessive with respect to hydrogen atoms. Therefore, the structure of the hydrocarbon constituting the carboxylic acid and the molecular weight and number of the carboxylic acid Correspondingly, the carboxylic acid takes away the heat of vaporization and vaporizes, and when the vaporization is completed, the metal precipitates.
Examples of such metal carboxylate compounds include metal octylate compounds, metal laurate compounds, and metal stearate compounds. Since the hydrocarbon has a branched structure, the octyl acid has a short chain length and a low boiling point of 228 ° C. Further, the boiling point of carboxylic acid having a linear structure of hydrocarbon is lower as the molecular weight of carboxylic acid is smaller, that is, the shorter the linear chain is, the boiling point of lauric acid is 296 ° C, and the boiling point of stearic acid is. It is 361 ° C. Therefore, these metal carboxylate compounds are thermally decomposed at a temperature of 290-430 ° C. in the atmospheric atmosphere according to the boiling point described above.
The metal carboxylate compound composed of unsaturated fatty acids has an excess of carbon atoms with respect to hydrogen atoms as compared with the metal carboxylate compound composed of saturated fatty acids. Therefore, metal oxides such as copper oleate are thermally decomposed. In the case of, the cuprous oxide Cu ₂ O and the cupric oxide Cu O are precipitated at the same time, and a treatment for reducing the cuprous oxide Cu ₂ O and the cupric oxide CuO to copper is required. In particular, cuprous oxide Cu ₂ O is once oxidized to cupric oxide Cu O in an atmosphere richer in oxygen than in the air atmosphere, and further reduced to copper in a reducing atmosphere, which increases the processing cost.
Further, the metal carboxylate compound is an inexpensive industrial chemical that can be easily synthesized. That is, when a carboxylic acid, which is the most general-purpose organic acid, is reacted with a strong alkali, a carboxylic acid alkali metal compound is produced, and when a carboxylic acid alkali metal compound is reacted with an inorganic metal compound, a carboxylic acid composed of various metals is produced. Metal compounds are synthesized. Therefore, it is the cheapest organometallic compound among the organometallic compounds. Therefore, the heat treatment temperature is higher than that of the metal complex composed of the inorganic metal compound described in paragraph 15, but the metal compound is cheaper than the metal complex.
Therefore, the method of covering the surface of the graphene junction described in paragraph 10 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum is thermally decomposed into silver, copper, gold, or aluminum. As a metal compound that precipitates any metal, the first feature is that the oxygen ion constituting the carboxyl group of the carboxylic acid is covalently bonded to the metal ion composed of any metal of silver, copper, gold, or aluminum. Using a metal carboxylate compound in which the carboxylic acid has the second characteristic of being a saturated fatty acid, the surface of the graphene conjugate described in paragraph 10 is made of any metal of silver, copper, gold, or aluminum. According to the method of covering with a collection of metal fine particles, the surface of the graphene junction is covered with a collection of metal fine particles made of any of silver, copper, gold, or aluminum.

The method of covering the surface of the graphene joint produced by the method described in paragraph 8 with a collection of fine particles made of an insulating metal oxide is described.
A metal compound in which an insulating metal oxide is precipitated by thermal decomposition is dispersed in methanol to prepare a methanol dispersion, and a graphene conjugate produced by the method described in paragraph 8 is placed on the bottom surface of the container. The formed container is filled, and vibrations in three directions of left and right, front and back, and up and down are repeatedly applied to the container to bring the surface of the graphene conjugate into contact with the methanol dispersion, and then the container is brought into contact with the metal. The temperature is raised to a temperature at which the compound is thermally decomposed, whereby the methanol is first vaporized, and a collection of fine crystals of the metal compound is simultaneously precipitated on the surface of the graphene conjugate, and then the metal compound is generated. The fine crystals of the oxide are thermally decomposed, and a collection of fine particles of the insulating metal oxide is deposited all at once on the surface of the graphene conjugate, and the surface is covered with the collection of fine particles of the insulating metal oxide. The surface of the graphene junction produced by the method described in paragraph 8 in which the graphene conjugate is formed on the bottom surface of the container as the shape of the bottom surface is covered with a collection of fine particles made of an insulating metal oxide. The method.

That is, first, a graphene joint is formed on the bottom surface of the container as the shape of the bottom surface by the manufacturing method described in paragraph 8. Next, a metal compound in which an insulating metal oxide is precipitated by thermal decomposition is dispersed in methanol, and the methanol dispersion is filled in the container in which a graphene conjugate is formed on the bottom surface of the container. The metal compound is dispersed in methanol to form a liquid phase. After that, when vibrations in three directions are repeatedly applied to the container, the surface of the graphene conjugate on the bottom surface of the container comes into contact with the methanol dispersion. As described in paragraph 11, since the graphene joint exists in the container, a vibration acceleration of about 0.2 G is applied. Further, the temperature of the container is raised to a temperature at which the metal compound is thermally decomposed. First, methanol is vaporized, and a collection of fine crystals of the metal compound is deposited all at once at the site of contact with the methanol dispersion of the graphene conjugate. That is, since the metal compound is dispersed in methanol in a molecular state in the methanol dispersion of the metal compound, when methanol is vaporized from the methanol dispersion, fine crystals of the metal compound are precipitated all at once. After that, fine crystals of the metal compound were thermally decomposed, and a collection of fine particles of insulating metal oxide was simultaneously deposited on the site of the graphene conjugate in contact with the methanol dispersion, that is, on the entire surface of the graphene conjugate. However, the entire surface of the graphene conjugate is covered with fine metal oxide particles. As a result, the surface of the graphene conjugate has the property of an insulating metal oxide. As the amount of the metal compound dispersed in methanol increases, the amount of metal oxide fine particles precipitated increases, and as a result, the amount of metal oxide fine particles precipitated on the surface of the graphene conjugate increases, and the metal oxide fine particles become compatible with each other. The entire surface of the graphene conjugate is covered with a collection of laminated and laminated metal oxide fine particles.
Among the metal oxides, magnetite Fe ₃ O ₄ (a type of iron oxide, also called triiron tetroxide) exists as a conductive metal oxide and has impurities, or from the chemical quantitative composition. As metal oxides whose insulating property is lowered by containing a component that shifts, there are metal oxides such as chromium CrO ₂ , nickel oxide NiO, zinc oxide ZnO, tin oxide SnO ₂ , and copper oxide CuO. Insulating metal oxides other than these metal oxides have high altitudes. For example, the Mohs hardness, aluminum oxide _Al 2 _{O 3} 9, chromium oxide _Cr 2 _{O 3} 8-8.5, is 7-7.5 titanium oxide TiO ₂ (rutile). On the other hand, the moth hardness of soft metals having excellent thermal conductivity and electrical conductivity is 2.5 for silver, 2.5-3 for copper, 2.5-3 for gold, and 2 for aluminum, as described above. Lower in altitude than insulating metal oxides. The volume resistivity of aluminum oxide Al ₂ O ₃ is 10 ^14-15 Ω · cm, titanium oxide TiO ₂ is 10 ⁷ Ω · cm, and chromium oxide Cr ₂ O ₃ is 10 ¹² Ω · cm, all of which are insulated. Highly sex. It should be noted that the metal oxide contains impurities or a component deviating from the stoichiometric composition, so that the insulating property is lowered. The above three types of highly insulating metal oxides are metal oxides having high insulating properties that do not contain substances deviating from the stoichiometric composition and do not contain impurities.

The method of covering the surface of the graphene conjugate described in paragraph 16 with a collection of fine particles made of an insulating metal oxide is described.
A metal compound in which an oxygen ion constituting a carboxyl group of a carboxylic acid serves as a ligand to coordinate-bond a metal carboxylic acid compound to a metal ion, and an insulating metal oxide is precipitated by thermal decomposition described in paragraph 16. It is a method of covering the surface of the graphene bond with a collection of fine particles made of an insulating metal oxide according to the method described in paragraph 16.

That is, the oxygen ion constituting the carboxyl group of the carboxylic acid serves as a ligand, and the metal carboxylic acid compound coordinated to the metal ion precipitates a metal oxide by thermal decomposition. Therefore, the method of covering the surface of the graphene conjugate described in paragraph 16 with a collection of fine particles of the insulating metal oxide is described as the above-mentioned carboxylic acid as a metal compound that precipitates the insulating metal oxide by thermal decomposition. When a metal compound is used and the surface of the graphene conjugate is covered with a collection of fine particles of insulating metal oxide according to the method described in paragraph 16, the surface of the graphene conjugate becomes electrically insulating. The thermal decomposition temperature of the metal carboxylate compound is the highest at which the metal naphthenate compound thermally decomposes at 330 ° C. Further, since the thermal decomposition of the carboxylic acid metal compound in the atmospheric atmosphere is 30 to 50 ° C. lower than the thermal decomposition in the nitrogen atmosphere, the thermal decomposition in the atmospheric atmosphere requires a low heat treatment cost. Further, the metal carboxylate compound is dispersed in methanol up to nearly 10% by weight.
That is, the carboxylic acid metal compound in which the oxygen ions constituting the carboxyl group act as a ligand and coordinate-bond close to the metal ion is because the oxygen ion approaches the metal ion, which is the largest ion, to coordinate-bond. , The distance between the two becomes shorter. Therefore, the oxygen ion coordinate-bonded to the metal ion has the longest distance from the ion covalently bonded on the opposite side of the metal ion. When the carboxylic acid metal compound having such molecular structural characteristics exceeds the boiling point of the carboxylic acid constituting the carboxylic acid metal compound, the oxygen ion constituting the carboxyl group is bonded to the ion covalently bonded on the opposite side of the metal ion. The part is first divided and decomposed into a metal oxide and a carboxylic acid, which are compounds of a metal ion and an oxygen ion. When the temperature is further raised, the carboxylic acid takes away the heat of vaporization and vaporizes, and the metal oxide precipitates immediately after the vaporization of the carboxylic acid is completed. Examples of such a metal carboxylate compound include a metal acetate compound, a metal caprylate oxide, a metal benzoate oxide, and a metal naphthenate oxide.
Since some of the metal acetate oxides precipitate metal oxides that have been amorphized by thermal decomposition and unstable metal oxides, the carboxylic acid metal oxide compound that precipitates metal oxides by thermal decomposition is capryl. A carboxylic acid metal oxide composed of an acid metal oxide, a benzoate metal oxide, and a naphthenate metal oxide is desirable.
In addition, the metal carboxylate compounds are inexpensive industrial chemicals that can be easily synthesized. That is, when a general-purpose carboxylic acid is reacted with a strong alkali, an alkali metal carboxylate compound is produced. After that, when the alkali metal carboxylate compound is reacted with the inorganic metal compound, the metal carboxylate compound is synthesized. The carboxylic acid used as a raw material is an organic acid having a relatively low boiling point among the boiling points of the organic acid, and a metal oxide is precipitated at a low heat treatment temperature of about 330 ° C. in an air atmosphere.
As described above, in the method of covering the surface of the graphene conjugate described in paragraph 16 with a collection of fine particles of insulating metal oxide, the insulating metal oxide described in paragraph 16 is precipitated by thermal decomposition. As the metal compound, a metal carboxylate compound in which an oxygen ion constituting the carboxyl group of the carboxylic acid serves as a ligand and is coordinated to the metal ion is used, and the surface of the graphene conjugate is prepared according to the method described in paragraph 16. This is a method of covering with a collection of fine particles made of an insulating metal oxide.

The method for removing the graphene conjugate produced by the method described in paragraph 16 from the container is as follows.
According to the method described in paragraph 16, a graphene junction whose surface is covered with a collection of fine particles of insulating metal oxide is formed on the bottom surface of the container as the shape of the bottom surface, and further above the graphene junction. By evenly compressing the planes of the graphene, frictional heat is generated at the sites where the metal oxide fine particles come into contact with each other in a collection of metal oxide fine particles formed on the surface layers of both planes of the graphene junction. Generated and the fine particles of the metal oxide are bonded to each other by the frictional heat. After that, the container is vibrated in three directions of front-back, left-right, and up-down, and the graphene junction is taken out from the container. It is a method of taking out a graphene conjugate produced by the described method from a container.

That is, when the surface of the graphene conjugate produced by the method described in paragraph 16 is covered with a collection of insulating metal oxide fine particles, the collection of metal oxide fine particles having no impurities and in an active state is formed. Precipitates on the surface of graphene conjugates. The fine particles of the metal oxide are precipitated by contacting the fine particles with each other, but since the fine particles of the metal oxide do not form a metal bond, the bonding force between the fine particles of the metal oxide is small. Therefore, when the graphene conjugate produced by the method described in paragraph 16 is taken out from the container, the fine particles of the metal oxide are easily dissociated from the graphene conjugate.
On the other hand, the insulating metal oxide has a high hardness as described in paragraph 17. In addition, the compression strength is also high. For example, the compressive strength of alumina is 3200 MPa, which is 16 times the tensile strength of copper. Therefore, when the upper flat surface of the graphene joint formed on the bottom surface of the container is uniformly compressed, the fine particles of the metal oxide formed on the surface layers of both planes of the graphene joint do not deform or break. Friction heat is generated at a portion where the fine particles come into contact with each other without reducing the applied compressive stress. The frictional heat causes the fine particles of metal oxide to join each other. As a result, both planes of the graphene junction are covered with a collection of fine particles of metal oxide bonded by frictional heat. After that, a vibration acceleration of about 0.2 G is applied to the container in three directions of front-back, left-right, and up-down, and the graphene joint is taken out from the container.
Since the metal oxide fine particles formed on the side surface of the graphene junction are in contact with the container, when the upper plane of the graphene junction is evenly compressed, the metal oxide fine particles are present on the side surface of the graphene junction. With respect to the metal fine particles formed on the side surface, frictional heat is generated at a portion where the metal oxide fine particles come into contact with each other, and the metal oxide fine particles are bonded to each other by the frictional heat. However, since the compressive stress acting on the metal oxide fine particles is not as large as the compressive stress acting on the metal oxide fine particles formed on both planes of the graphene joint, the bonding force between the metal oxide fine particles is large. , It is smaller than the bonding force between the fine particles of the metal oxide formed on both planes of the graphene bonded body.
In this graphene junction, the metal oxide fine particles on the surface layer are bonded to each other by frictional heat, and the collection of the metal oxide fine particles has a certain bonding force. This allows the graphene conjugate removed from the container to be handled.
Since a collection of fine metal oxide fine particles bonded by frictional heat is formed on both planes of the graphene bonded body, the graphene bonded body can be pressure-bonded to a base material or a component. That is, when the graphene joint is placed on the surface of the component or the base material and the plane of the graphene joint is evenly compressed, the fine particles of the metal oxide on one plane of the graphene joint bite into the surface of the part or the base material. .. As a result, the graphene joint is crimped to the component or the base material, and the other flat surface of the crimped graphene joint has an insulating property. As a result, a graphene joint having excellent thermal conductivity and electrical conductivity and an insulating surface is pressure-bonded to the component or the base material.

It is explanatory drawing which enlarged and represented a part of the side surface of the graphene junction in which the flat planes of graphene overlapped.

Example 1
This embodiment is an example in which a graphene junction composed of a collection of graphene obtained by joining the flat planes in which the flat planes of graphene overlap each other is formed on the bottom surface of the container according to the manufacturing method described in paragraph 8. ..
First, 2 liters of methanol was filled into a container having a bottom surface of 1.2 m × 1.2 m and a shallow bottom.
Next, a parallel plate electrode having an effective area of 1 m × 1 m in which an electric field is generated in the gap between the two parallel plate electrodes is prepared, and the two parallel plate electrodes are superposed with a gap of 100 μm, and this gap is formed. The graphite particles are evenly packed. Assuming that the graphite particles are spheres having a particle size of 25 μm and the average thickness of the graphite particles is 10 μm, the graphite particles are evenly packed in the gap of 100 μm formed by the two parallel plate electrodes. In the case, there are 6.4 × 10 ⁷ graphite particles. When a DC voltage of 10.6 kilovolts or more is applied to this group of graphite particles, the interlayer bonds on the basal planes of all the graphite particles are simultaneously broken. At this time, an aggregate of 1.9 × 10 ¹³ graphenes was obtained, and the aggregate of graphite particles used was only 1.18 g.
Therefore, 10 g of scaly graphite particles (for example, XD100 manufactured by Ito Graphite Industry Co., Ltd.) were stacked and pulled on the surface of a parallel plate electrode having an effective area of an electrode in which an electric field is generated of 1 m × 1 m. This parallel plate electrode was immersed in a container filled with methanol, and the other parallel plate electrode was superposed on the parallel plate electrode, and the two parallel plate electrodes were separated by a gap of 100 μm. A DC voltage of 12 kilovolts was applied between the electrodes. Next, the gap between the two parallel plate electrodes is expanded, the two parallel plate electrodes are tilted in methanol, and vibration acceleration in three directions consisting of 0.2 G is repeatedly applied to the container, and then the container is used. Two parallel plate electrodes were taken out from. Further, ultrasonic vibration of 20 kHz was applied to methanol in the container for 2 minutes by an ultrasonic homogenizer device (product LUH300 of Yamato Scientific Co., Ltd.). After that, vibration acceleration in three directions consisting of 0.2 G was repeatedly applied to the container.
Next, the temperature of the container was raised to 65 ° C., and methanol was vaporized. Further, a 1.2 m × 1.2 m aluminum plate is placed on the upper flat surface of the sample formed on the bottom surface of the container, and a 50 kg weight is placed on the aluminum plate to evenly place the upper flat surface of the sample. Compressed. After removing the weight and the aluminum plate, a vibration acceleration of 0.2 G in three directions was applied to the container, and the sample was taken out from the container. An aluminum plate was placed again on the sample taken out, and a weight of 10 kg was further placed, but the state of the sample did not change.
Next, the two planes and sides of the sample were observed and analyzed using an electron microscope. As the electron microscope, an extremely low accelerating voltage SEM manufactured by JFE Techno Research Co., Ltd. was used. This device can observe the surface with an extremely low accelerating voltage from 100 volts, and has the feature that the surface of the sample can be directly observed without forming a conductive film on the sample. First, the secondary electron beam between 900 and 1000 volts of the backscattered electron beam from the plane of the sample was taken out and image processed. An extremely thin step was confirmed on the flat surface of the sample. Next, the secondary electron beam between 900 and 1000 volts of the backscattered electron beam from the side surface of the sample was taken out and image processing was performed. Ten layers of extremely thin substances were stacked. Furthermore, as a result of image processing of the energy of the characteristic X-ray and its intensity, it was confirmed that only carbon atoms were present and the sample was a graphene conjugate in which the flat planes of graphene overlapped with each other.
In FIG. 1, a part of the side surface of the graphene junction in which the flat surfaces of graphene overlap each other is enlarged and schematically shown. 1 is graphene.
Even if the graphene joint was taken out from the container and a weight of 10 kg was placed on the graphene joint, the graphene joint was not destroyed, so that the flat surfaces of the graphene were joined with a constant joining force.

Example 2
This example is an example in which the surface of the graphene junction formed on the bottom surface of the container in Example 1 is covered with a collection of silver fine particles.
First, a metal compound that precipitates silver by thermal decomposition is dispersed in methanol to prepare a methanol dispersion. As a silver compound, two ammines, which are one of the most easily synthesized silver complex ions, are chlorides of diammine silver ion [Ag (NH ₃ ) ₂ ] ^{+ 1} coordinated to silver ion Ag ^+. Using diammine silver chloride [Ag (NH ₃ ) ₂ ] Cl (for example, a product of Tanaka Kikinzoku Sales Co., Ltd.), 0.1 mol of diammine silver chloride was dispersed in 100 cc of methanol. In Example 1, this methanol dispersion was filled in a container in which a graphene conjugate was formed on the bottom surface of the container in the shape of the bottom surface. Next, vibration acceleration in three directions consisting of 0.2 G was repeatedly applied to the container. Further, the container was heated to 180 ° C. in an atmosphere of hydrogen gas and left at 180 ° C. for 5 minutes. After that, vibration acceleration in three directions consisting of 0.2 G was applied to the container again for a short time, and the sample was taken out from the bottom of the container.
Next, the two planes and sides of the sample were observed and analyzed with the electron microscope used in Example 1. First, the secondary electron beam between 900 and 1000 volts of the backscattered electron beam was taken out and image processed. Granular particles having a size of 40-60 nm were evenly formed on both the plane and the side surface. Next, the energy between 900 and 1000 volts of the reflected electron beam was extracted and image processing was performed, and the difference in material was observed depending on the shade of the image. Since no shade was observed, it was formed from the same substance. Furthermore, the energy of the characteristic X-ray and its intensity were image-processed, and the elements constituting the fine particles were analyzed. It was found that only silver atoms were present and the granular fine particles were silver fine particles.
Next, a collection of silver fine particles formed on the side surface of the sample was peeled off, and the secondary electron beam between 900 and 1000 volts of the backscattered electron beam from the side surface of the sample was taken out and image processing was performed. Similar to the side surface of Example 1, a graphene junction in which the flat surfaces of graphene overlapped with each other could be observed. From this result, it was found that the surface of the graphene conjugate was covered with a collection of silver fine particles.
As described above, in Example 1, a graphene junction in which the flat surfaces of graphene are joined is formed on the bottom surface of the container, and in Example 2, a collection of silver fine particles is deposited on the surface of the graphene junction. , The surface of the graphene conjugate was covered with silver fine particles. After that, a vibration acceleration of 0.2 G in three directions was applied to the container for a short time, and the sample was taken out from the bottom of the container. At this time, since the silver fine particles were not peeled off from the graphene joint, it was found that the collection of silver fine particles covered the graphene joint with a certain strength. Therefore, the graphene joint can be handled, and when the graphene joint is placed on the base material or parts and the graphene joint is compressed, the graphene joint is crimped to the base material or parts via silver fine particles and crimped. The graphene conjugate exhibits the thermal conductivity of graphene and the conductivity of silver.

Example 3
This example is an example in which the surface of the graphene junction formed on the bottom surface of the container in Example 1 is covered with a collection of fine particles of aluminum oxide Al ₂ O ₃ . Aluminum oxide is an insulator having a volume resistivity of 10 ^14-15 Ω · cm and a dielectric strength of 10-15 kilovolts / mm.
First, 0.1 mol of aluminum benzoate Al (C ₆ H ₅ COO) ₃ (for example, a product of Mitsuwa Chemical Co., Ltd.) was dispersed in 100 cc of methanol to prepare a methanol dispersion. In Example 1, this methanol dispersion was filled in a container in which a graphene conjugate was formed on the bottom surface of the container in the shape of the bottom surface.
Next, vibration acceleration in three directions consisting of 0.2 G was repeatedly applied to the container. Further, the container was heated to 310 ° C. in an air atmosphere and left at 310 ° C. for 1 minute. After that, as in Example 1, an aluminum plate was placed on a flat surface above the sample in the container, a weight of 20 kg was further placed, and then the weight and the aluminum plate were taken out. Further, a vibration acceleration of 0.2 G in three directions was applied to the container for a short time, and the sample was taken out from the container. A weight of 5 kg was placed on the sample taken out again, but the fine particles were not peeled off from the surface of the sample.
After that, as in Example 2, the two planes and sides of the sample were observed and analyzed with an electron microscope. Granular fine particles having a size of 40-60 nm were evenly stacked and formed on both the flat surface and the side surface, and the granular fine particles were composed of aluminum oxide.
After that, all the aggregates of granular fine particles on the side surface were stripped off, and the side surface was observed again with an electron microscope. As a result, similarly to the side surface of Example 1, a graphene junction in which the flat surfaces of graphene overlapped with each other could be observed.
From this result, it was found that the surface of the graphene conjugate was covered with a collection of fine particles of aluminum oxide. Further, even if the graphene joint was taken out from the container and a weight of 5 kg was placed on the graphene joint, the fine particles of aluminum oxide were not dissociated from the graphene joint. Therefore, when the weight of 20 kg was placed on the graphene joint, it was oxidized. It was found that the aluminum fine particles were bonded to each other by frictional heat, and a collection of aluminum oxide fine particles covered the surface of the graphene bonded body with a constant strength.
From the above results, in Example 1, a graphene joint in which the flat surfaces of graphene were joined was formed on the bottom surface of the container, and in Example 3, a collection of fine particles of aluminum oxide was deposited on the surface of the graphene joint. , The surface of the graphene conjugate was covered with a collection of fine particles of aluminum oxide. After that, when compressive stress was evenly applied to the entire plane of the graphene bonded body, the fine particles of aluminum oxide were bonded by frictional heat at the sites where they were in contact with each other. Therefore, the graphene joint can be handled, and when the graphene joint is placed on the base material or parts and the graphene joint is compressed, the graphene joint is crimped to the base material or parts via fine particles of aluminum oxide. The crimped graphene joint has the thermal conductivity of graphene, and the surface exhibits insulating properties.

1 Graphene

Claims (7)

A method for producing a graphene junction composed of a collection of graphene obtained by joining the flat planes in which the flat planes of graphene overlap each other is
A collection of scaly graphite particles or a collection of massive graphite particles is flatly packed on the surface of one of the two parallel plate electrodes, and the parallel plate electrode is immersed in methanol filled in a container. Further, the other parallel plate electrode is superposed on the one parallel plate electrode, and the two parallel plate electrodes are separated from each other through a collection of the scaly graphite particles or a collection of the massive graphite particles. , The two separated parallel plate electrodes are immersed in the methanol, and then a DC potential difference is applied to the gap between the two parallel plate electrodes, whereby the magnitude of the potential difference is increased to the above 2. An electric field corresponding to the value divided by the size of the gap between the parallel plate electrodes is applied to the group of scaly graphite particles or the group of lump graphite particles, and the application of the electric field causes the scaly graphite particles or All of the interlayer bonds of the basal plane forming the massive graphite particles are simultaneously destroyed, and a collection of graphene corresponding to the basal plane is produced in the gap between the two parallel plate electrodes. The gap between the parallel plate electrodes is expanded, the two parallel plate electrodes are tilted in the methanol, and vibrations in three directions of left and right, front and back, and up and down are repeatedly applied to the container to collect the graphene. It is moved into the methanol through the gap between the two parallel graphite plates, and then the two parallel graphite electrodes are taken out from the container, and the container is repeatedly vibrated in three directions of front-back, left-right, and up-down. In addition, a collection of graphene in which the flat planes of the graphene are overlapped with each other via methanol is formed on the bottom surface of the container as the shape of the bottom surface, and then the temperature of the container is raised to the boiling point of the graphite. Methanol is vaporized to form a group of graphene on which the flat planes of the graphene overlap each other as the shape of the bottom surface of the container, and then the plane above the group of graphene is evenly compressed. A collection of graphene in which frictional heat is generated at a portion where the graphite flat surfaces overlap each other, the graphite flat surfaces are joined to each other by the frictional heat, and the graphite flat surfaces are joined to each other. A graphene junction made of graphite is formed on the bottom surface of the container as the shape of the bottom surface, and is a method for producing a graphene junction composed of a collection of graphite obtained by joining the graphite flat surfaces on which the graphite flat surfaces are overlapped. is there. A method of covering the surface of the graphene joint produced by the method according to claim 1 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum.
A metal compound in which any metal of silver, copper, gold, or aluminum is precipitated by thermal decomposition is dispersed in methanol to prepare a methanol dispersion, and the methanol dispersion is produced by the method according to claim 1. The graphene bond is filled in the container formed on the bottom surface of the container, and the container is repeatedly vibrated in three directions of left and right, front and back, and up and down to bring the surface of the graphene bond into contact with the methanol dispersion. After that, the temperature of the container is raised to a temperature at which the metal compound is thermally decomposed, whereby the methanol is first vaporized, and a collection of fine crystals of the metal compound is simultaneously gathered on the surface of the graphene bond. After that, the fine crystals of the metal compound are thermally decomposed, and a collection of granular metal fine particles made of any metal of silver, copper, gold, or aluminum is simultaneously gathered on the surface of the graphene bond. The surface of the graphene bonded body is a metal fine particle made of any of the metal-bonded silver, copper, gold, or aluminum, which is deposited on the metal and is metal-bonded at a site where the granular metal fine particles are in contact with each other. A method of covering the surface of a graphene bond produced by the method according to claim 1, which is covered with an aggregate, with an aggregate of metal fine particles made of any metal of silver, copper, gold, or aluminum. The method of covering the surface of the graphene joint according to claim 2 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum.
Claims a metal complex composed of an inorganic metal compound having a metal complex ion in which a ligand composed of an inorganic ion or a molecule is coordinated to a metal ion composed of a metal of silver, copper, gold, or aluminum. The silver, copper, gold, or aluminum metal described in 2 is used as a metal compound that is precipitated by thermal decomposition, and the surface of the graphene conjugate is coated with silver, copper, gold, according to the method described in claim 2. Or it is a method of covering with a collection of metal fine particles made of any metal of aluminum. The method of covering the surface of the graphene joint according to claim 2 with a collection of metal fine particles made of any of silver, copper, gold, or aluminum.
The first feature that the oxygen ion constituting the carboxyl group of the carboxylic acid is covalently bonded to the metal ion made of any metal of silver, copper, gold or aluminum, and the second feature that the carboxylic acid is made of a saturated fatty acid. A metal carboxylate compound having both characteristics is used as a metal compound in which any metal of silver, copper, gold, or aluminum according to claim 2 is precipitated by thermal decomposition, and according to the method according to claim 2. This is a method of covering the surface of a graphene joint with a collection of metal fine particles made of any of silver, copper, gold, or aluminum. A method of covering the surface of the graphene conjugate produced by the method according to claim 1 with a collection of fine particles made of an insulating metal oxide is described.
A graphene conjugate obtained by dispersing a metal compound in which an insulating metal oxide is thermally decomposed in methanol to prepare a methanol dispersion and producing the methanol dispersion by the method according to claim 1 is the bottom surface of the container. The container formed in the above is filled, and further, vibrations in three directions of left and right, front and back, and up and down are repeatedly applied to the container to bring the surface of the graphene conjugate into contact with the methanol dispersion, and then the container. The temperature is raised to a temperature at which the metal compound is thermally decomposed, whereby the methanol is first vaporized, and a collection of fine crystals of the metal compound is deposited all at once on the surface of the graphene conjugate, and then The fine crystals of the metal compound are thermally decomposed, and a collection of fine particles of the insulating metal oxide is deposited all at once on the surface of the graphene conjugate, and the surface is formed by the collection of fine particles of the insulating metal oxide. The surface of the graphene junction produced by the method according to claim 1, wherein the graphene conjugate covered with is formed on the bottom surface of the container as the shape of the bottom surface, is formed of fine particles made of an insulating metal oxide. It is a method of covering with a group of. The method of covering the surface of the graphene conjugate according to claim 5 with a collection of fine particles made of an insulating metal oxide is described.
A metal in which an insulating metal oxide is precipitated by thermal decomposition according to claim 5, wherein an oxygen ion constituting the carboxyl group of the carboxylic acid serves as a ligand to coordinate-bond the carboxylic acid metal compound to the metal ion. It is a method of using as a compound and covering the surface of a graphene conjugate with a collection of fine particles made of an insulating metal oxide according to the method according to claim 5. The method for taking out the graphene conjugate produced by the method according to claim 5 from the container is
According to the method according to claim 5, a graphene junction whose surface is covered with a collection of fine particles made of an insulating metal oxide is formed on the bottom surface of the container as the shape of the bottom surface, and further, above the graphene junction. By evenly compressing the planes of the graphene, frictional heat is generated at the sites where the metal oxide fine particles come into contact with each other in a collection of metal oxide fine particles formed on the surface layers of both planes of the graphene junction. 5. The graphene bonded body is taken out from the container by applying vibrations in three directions of front-back, left-right, and up-down to the container, which is generated and the fine particles of the metal oxide are bonded to each other by the frictional heat. This is a method of taking out the graphene conjugate produced by the method described in 1.