Mining of graphene
Publish: 2021-05-12 05:02:33
1.
Graphene, graphene, is the underlying technology architecture of blockchain created by EOS founder Daniel Larimer and cryptonomex team. Based on this architecture, Daniel has developed bitshares, stem, EOS and other far-reaching projects. The famous blockchain projects developed based on this architecture include Zoomlion auto chain, gongxinbao, karma, payger, echo, seer and so on
Zac chain is an electric vehicle intelligent ecosystem based on blockchain technology. Supported by the core technology of blockchain, supplemented by AI, big data, Internet of things and other technologies, and based on the vehicle traveling data recorder tntelligent tree as the carrier, it customizes an intelligent experience service system for electric vehicle users, covering both the front market and the back market. In the Zac chain network, users can fully control their own driving data, and enter the mining mode from the blockchain technology. Driving is mining, and driving is value. The Zac token generated by mining can be exchanged in the Zac chain ecosystem to solve the pain point of depreciation of users' car use
2. There is no graphene mining right, but there is graphite mining right; Graphene is a kind of proct. At present, there are also listed companies procing graphene! The first listed company mainly engaged in graphene in China is Changzhou sixth element material technology Co., Ltd.
Stock Code: 831190
Stock Code: 831190
3. Graphene appeared in the laboratory in 2004, when two British scientists, Andre Jem and Kostya Novoselov, discovered that they could get thinner and thinner sheets of graphite in a very simple way. They peel the graphite sheet from the graphite, then stick both sides of the sheet to a special tape, tear the tape, and the graphite sheet can be divided into two. And they kept doing this, and the sheets got thinner and thinner, and finally they got a sheet of carbon atoms, which is graphene. After five years of development, people found that it is not far to bring graphene into the field of instrial proction< There are two main synthesis methods of graphene: mechanical method and chemical method. Mechanical methods include micromechanical separation, oriented epitaxy and SIC heating; Chemical methods are chemical rection and chemical cleavage
micromechanical separation
the most common method is micromechanical separation, which directly cuts the graphene sheet from the larger crystal. In 2004, novoselovt et al. Prepared graphene monolayers by this method, which can exist stably in the external environment. The typical preparation method is to use another material to expand or introce defects of pyrolytic graphite for friction, the surface of bulk graphite will proce flocculent crystals, in which there is a single layer of graphene. But the disadvantage of this method is that it is difficult to control the size of the single-layer graphene sheet by using the sheet obtained by rubbing the graphite surface, and it is unable to reliably manufacture the graphite sheet with enough length for application< In this method, carbon atoms are first infiltrated into ruthenium at 1150 ℃, and then cooled. After cooling to 850 ℃, a large number of previously absorbed carbon atoms will float to the surface of ruthenium, and monolayer "islands" of carbon atoms in the shape of lens cover the whole surface of the substrate, Eventually they grow into a complete layer of graphene. After the first layer was covered by 80%, the second layer began to grow. The graphene in the bottom layer has strong interaction with ruthenium, while the graphene in the second layer is almost completely separated from ruthenium, leaving only weak electric coupling. The graphene sheet obtained is satisfactory. However, the thickness of graphene sheet proced by this method is often uneven, and the adhesion between graphene and matrix will affect the characteristics of carbon layer. In addition, the matrix used by Peter W. Sutter is rare metal ruthenium
heating SiC method
in this method, Si is removed by heating single crystal 6h SiC, and graphene layers are decomposed on (0001) surface of single crystal. The specific process is as follows: the oxygen or hydrogen etched sample is heated by electron bombardment in high vacuum to remove oxide. After the oxide on the surface is completely removed by AES, the sample is heated to 1250 ~ 1450 ℃ and then kept at constant temperature for 1 min ~ 20 min to form a very thin graphite layer. Berger et al. Have been able to prepare monolayer or multilayer graphene under control after several years of exploration. The thickness of graphene is determined by heating temperature, so it is difficult to prepare large area graphene with single thickness. It is a new way to prepare high-quality free standing graphene materials by pyrolysis of commercial SiC particles. The structure and size of graphene can be controlled by controlling raw SiC particles, pyrolysis temperature, pyrolysis rate and atmosphere. This is a very novel preparation method, which is very important for the practical application of graphene
chemical rection method
the chemical rection method is to mix graphite oxide and water in the ratio of 1 mg / ml, shake the solution with ultrasonic wave until the solution is clear and free of granular substances, add appropriate amount of hydrazine, reflux at 100 ℃ for 24 h to proce black granular precipitation, filter and dry to obtain graphene. Sasha stankovich et al. Prepared graphene with a thickness of about 1 nm by chemical dispersion method[ 3]
chemical cleavage method
chemical cleavage method is a method of preparing graphene from graphite oxide by thermal rection. The oxygen-containing functional groups between the layers of graphite oxide react at a certain temperature to rapidly release gas, so that the graphene layer can be reced and cleaved at the same time to obtain graphene. This is an important method to prepare graphene. Yang Quanhong of Tianjin University prepared high quality graphene by low temperature chemical cleavage of graphite oxide.
micromechanical separation
the most common method is micromechanical separation, which directly cuts the graphene sheet from the larger crystal. In 2004, novoselovt et al. Prepared graphene monolayers by this method, which can exist stably in the external environment. The typical preparation method is to use another material to expand or introce defects of pyrolytic graphite for friction, the surface of bulk graphite will proce flocculent crystals, in which there is a single layer of graphene. But the disadvantage of this method is that it is difficult to control the size of the single-layer graphene sheet by using the sheet obtained by rubbing the graphite surface, and it is unable to reliably manufacture the graphite sheet with enough length for application< In this method, carbon atoms are first infiltrated into ruthenium at 1150 ℃, and then cooled. After cooling to 850 ℃, a large number of previously absorbed carbon atoms will float to the surface of ruthenium, and monolayer "islands" of carbon atoms in the shape of lens cover the whole surface of the substrate, Eventually they grow into a complete layer of graphene. After the first layer was covered by 80%, the second layer began to grow. The graphene in the bottom layer has strong interaction with ruthenium, while the graphene in the second layer is almost completely separated from ruthenium, leaving only weak electric coupling. The graphene sheet obtained is satisfactory. However, the thickness of graphene sheet proced by this method is often uneven, and the adhesion between graphene and matrix will affect the characteristics of carbon layer. In addition, the matrix used by Peter W. Sutter is rare metal ruthenium
heating SiC method
in this method, Si is removed by heating single crystal 6h SiC, and graphene layers are decomposed on (0001) surface of single crystal. The specific process is as follows: the oxygen or hydrogen etched sample is heated by electron bombardment in high vacuum to remove oxide. After the oxide on the surface is completely removed by AES, the sample is heated to 1250 ~ 1450 ℃ and then kept at constant temperature for 1 min ~ 20 min to form a very thin graphite layer. Berger et al. Have been able to prepare monolayer or multilayer graphene under control after several years of exploration. The thickness of graphene is determined by heating temperature, so it is difficult to prepare large area graphene with single thickness. It is a new way to prepare high-quality free standing graphene materials by pyrolysis of commercial SiC particles. The structure and size of graphene can be controlled by controlling raw SiC particles, pyrolysis temperature, pyrolysis rate and atmosphere. This is a very novel preparation method, which is very important for the practical application of graphene
chemical rection method
the chemical rection method is to mix graphite oxide and water in the ratio of 1 mg / ml, shake the solution with ultrasonic wave until the solution is clear and free of granular substances, add appropriate amount of hydrazine, reflux at 100 ℃ for 24 h to proce black granular precipitation, filter and dry to obtain graphene. Sasha stankovich et al. Prepared graphene with a thickness of about 1 nm by chemical dispersion method[ 3]
chemical cleavage method
chemical cleavage method is a method of preparing graphene from graphite oxide by thermal rection. The oxygen-containing functional groups between the layers of graphite oxide react at a certain temperature to rapidly release gas, so that the graphene layer can be reced and cleaved at the same time to obtain graphene. This is an important method to prepare graphene. Yang Quanhong of Tianjin University prepared high quality graphene by low temperature chemical cleavage of graphite oxide.
4. It is not difficult to judge whether the automatic coin digging of graphene GPC free ore feeder is a pyramid scheme fraud
to seek illegal benefits, disrupt economic order and affect social stability by calculating and paying remuneration to the developed personnel based on their number of directly or indirectly developed personnel or sales performance, or requiring the developed personnel to obtain the qualification to join in on the condition of paying certain fees.
to seek illegal benefits, disrupt economic order and affect social stability by calculating and paying remuneration to the developed personnel based on their number of directly or indirectly developed personnel or sales performance, or requiring the developed personnel to obtain the qualification to join in on the condition of paying certain fees.
5. Graphene is a two-dimensional crystal composed of carbon atoms with only one layer of atomic thickness. In 2004, physicists Andre Geim and Konstantin Novoselov of the University of Manchester, UK, successfully separated graphene from Shi Mozhong, confirmed that it can exist alone, and the two won the 2010 Nobel prize in physics.
before the discovery of graphene in 2015, graphene was not only the thinnest material, but also the strongest material, and its fracture strength was 200 times higher than that of the best steel. At the same time, it has good elasticity, and the stretching range can reach 20% of its own size. It is the thinnest and strongest material in nature at present. If you use a piece of graphene with an area of 1 square meter to make a hammock, and its weight is less than 1 mg, you can bear a one kilogram cat
the most potential application of graphene at present is to become a substitute for silicon, to manufacture ultramicro transistors, and to proce future supercomputers. With graphene instead of silicon, computer processors will run hundreds of times faster.
before the discovery of graphene in 2015, graphene was not only the thinnest material, but also the strongest material, and its fracture strength was 200 times higher than that of the best steel. At the same time, it has good elasticity, and the stretching range can reach 20% of its own size. It is the thinnest and strongest material in nature at present. If you use a piece of graphene with an area of 1 square meter to make a hammock, and its weight is less than 1 mg, you can bear a one kilogram cat
the most potential application of graphene at present is to become a substitute for silicon, to manufacture ultramicro transistors, and to proce future supercomputers. With graphene instead of silicon, computer processors will run hundreds of times faster.
6.
Methods of making graphene:
1. Mechanical stripping method
mechanical stripping method is a method to obtain graphene thin layer materials by using the friction and relative motion between objects and graphene. The operation of this method is simple, and the obtained graphene usually maintains a complete crystal structure. In 2004, two British scientists used transparent tape to peel natural graphite layer by layer to obtain graphene, which was also classified as mechanical stripping method
Second, the oxidation-rection method is to use sulfuric acid, nitric acid and other chemical reagents, potassium permanganate, hydrogen peroxide and other oxidants to oxidize natural graphite, increase the spacing between graphite layers, and insert oxide between graphite layers to prepare graphite oxide. Then, the reactant was washed with water, and the washed solid was dried at low temperature to prepare graphite oxide powder. Graphene oxide was prepared by physical exfoliation and high temperature expansion Third, oriented epitaxy methodoriented epitaxy method is to use the growth matrix atomic structure to "seed" graphene, first let the carbon atoms infiltrate into ruthenium at 1150 ℃, and then cool. After cooling to 850 ℃, a large number of previously absorbed carbon atoms will float to the ruthenium surface, and finally the single-layer carbon atoms with lens shape will grow into a complete layer of graphene
After the first layer was covered, the second layer began to grow. The graphene in the bottom layer will have strong interaction with ruthenium, while the graphene in the second layer will almost completely separate from ruthenium, leaving only weak electrical coupling. However, the thickness of graphene sheet proced by this method is often uneven, and the adhesion between graphene and matrix will affect the characteristics of carbon layer The silicon carbide epitaxy method is to sublimate the silicon atoms out of the material in the high temperature environment of ultra-high vacuum, and the remaining C atoms are reconstructed by self-assembly, so as to obtain graphene based on SiC substrate. This method can obtain high quality graphene, but this method requires high equipment Chemical vapor deposition (CVD) is a method of preparing graphene thin films by using carbon containing organic gas as raw material. This is the most effective way to proce graphene film. Graphene prepared by this method has the characteristics of large area and high quality, but the cost is high at present, and the process conditions need to be further improved reference sources: Network graphene
7. Graphene is a two-dimensional crystal composed of carbon atoms, which is separated from graphite and has only one layer of atomic thickness< There are two main synthesis methods of graphene: mechanical method and chemical method. Mechanical methods include micromechanical separation, oriented epitaxy and SIC heating; Chemical methods are chemical rection and chemical dissociation
micromechanical separation
the most common method is micromechanical separation, which directly cuts the graphene sheet from the larger crystal. In 2004, novoselovt et al. Prepared graphene monolayers by this method, which can exist stably in the external environment. The typical preparation method is to use another material to expand or introce defects of pyrolytic graphite for friction, the surface of bulk graphite will proce flocculent crystals, in which there is a single layer of graphene. But the disadvantage of this method is that it is difficult to control the size of the single-layer graphene sheet by using the sheet obtained by rubbing the graphite surface, and it is unable to reliably manufacture the graphite sheet with enough length for application
oriented epitaxy - crystal film growth
oriented epitaxy is to "seed" graphene by using the atomic structure of the growth matrix. First, carbon atoms are infiltrated into ruthenium at 1150 ℃, and then cooled. After cooling to 850 ℃, a large number of previously absorbed carbon atoms will float to the surface of ruthenium, and the lens like monolayer of carbon atoms "islands" cover the whole surface of the matrix, Eventually they grow into a complete layer of graphene. After the first layer is covered by 80%, the second layer begins to grow. The graphene in the bottom layer has strong interaction with ruthenium, while the graphene in the second layer is almost completely separated from ruthenium, leaving only weak electric coupling. The graphene sheet obtained is satisfactory. However, the thickness of graphene sheet proced by this method is often uneven, and the adhesion between graphene and matrix will affect the characteristics of carbon layer. In addition, the matrix used by Peter W. Sutter is rare metal ruthenium
heating SiC method
in this method, Si is removed by heating single crystal 6h SiC, and graphene layers are decomposed on (0001) surface of single crystal. The specific process is as follows: the oxygen or hydrogen etched sample is heated by electron bombardment in high vacuum to remove oxide. After the oxide on the surface is completely removed by AES, the sample is heated to 1250 ~ 1450 ℃ and then kept at constant temperature for 1 min ~ 20 min to form a very thin graphite layer. Berger et al. Have been able to prepare monolayer or multilayer graphene under control after several years of exploration. The thickness of graphene is determined by heating temperature, so it is difficult to prepare large area graphene with single thickness
baoxinhe et al. Have developed a new way to prepare high-quality free standing graphene materials by pyrolysis of commercial SiC particles. The structure and size of graphene can be controlled by controlling raw SiC particles, pyrolysis temperature, pyrolysis rate and atmosphere. This is a very novel preparation method, which is very important for the practical application of graphene
chemical rection method
the chemical rection method is to mix the graphite oxide and water at the ratio of 1 mg / ml, shake the solution with ultrasonic wave until it is clear and has no granular substance, add an appropriate amount of hydrazine, reflux at 100 ℃ for 24 h to proce black granular precipitation, filter and dry to obtain graphene. Sasha stankovich et al. Prepared graphene with a thickness of about 1 nm by chemical dispersion method
chemical dissociation method
chemical dissociation method is a method of preparing graphene from graphite oxide by thermal rection, and the oxygen-containing functional groups in the graphite oxide layers react at a certain temperature
one or more gaseous substances are introced into a reaction chamber for chemical reaction to proce a new material deposited on the substrate surface. The specific method is to decompose gaseous organic compounds containing carbon atoms such as methane (CH4) and acetylene (C2H2) on metal substrates such as nickel or copper at high temperature, and the carbon atoms with hydrogen atoms will be deposited and adsorbed on the metal surface to form graphene continuously
the gas is released rapidly, which makes the graphite oxide layer be reced and cleaved at the same time to get graphene. This is an important method to prepare graphene. Yang Quanhong of Tianjin University prepared high quality graphene by chemical dissociation of graphite oxide at low temperature.
micromechanical separation
the most common method is micromechanical separation, which directly cuts the graphene sheet from the larger crystal. In 2004, novoselovt et al. Prepared graphene monolayers by this method, which can exist stably in the external environment. The typical preparation method is to use another material to expand or introce defects of pyrolytic graphite for friction, the surface of bulk graphite will proce flocculent crystals, in which there is a single layer of graphene. But the disadvantage of this method is that it is difficult to control the size of the single-layer graphene sheet by using the sheet obtained by rubbing the graphite surface, and it is unable to reliably manufacture the graphite sheet with enough length for application
oriented epitaxy - crystal film growth
oriented epitaxy is to "seed" graphene by using the atomic structure of the growth matrix. First, carbon atoms are infiltrated into ruthenium at 1150 ℃, and then cooled. After cooling to 850 ℃, a large number of previously absorbed carbon atoms will float to the surface of ruthenium, and the lens like monolayer of carbon atoms "islands" cover the whole surface of the matrix, Eventually they grow into a complete layer of graphene. After the first layer is covered by 80%, the second layer begins to grow. The graphene in the bottom layer has strong interaction with ruthenium, while the graphene in the second layer is almost completely separated from ruthenium, leaving only weak electric coupling. The graphene sheet obtained is satisfactory. However, the thickness of graphene sheet proced by this method is often uneven, and the adhesion between graphene and matrix will affect the characteristics of carbon layer. In addition, the matrix used by Peter W. Sutter is rare metal ruthenium
heating SiC method
in this method, Si is removed by heating single crystal 6h SiC, and graphene layers are decomposed on (0001) surface of single crystal. The specific process is as follows: the oxygen or hydrogen etched sample is heated by electron bombardment in high vacuum to remove oxide. After the oxide on the surface is completely removed by AES, the sample is heated to 1250 ~ 1450 ℃ and then kept at constant temperature for 1 min ~ 20 min to form a very thin graphite layer. Berger et al. Have been able to prepare monolayer or multilayer graphene under control after several years of exploration. The thickness of graphene is determined by heating temperature, so it is difficult to prepare large area graphene with single thickness
baoxinhe et al. Have developed a new way to prepare high-quality free standing graphene materials by pyrolysis of commercial SiC particles. The structure and size of graphene can be controlled by controlling raw SiC particles, pyrolysis temperature, pyrolysis rate and atmosphere. This is a very novel preparation method, which is very important for the practical application of graphene
chemical rection method
the chemical rection method is to mix the graphite oxide and water at the ratio of 1 mg / ml, shake the solution with ultrasonic wave until it is clear and has no granular substance, add an appropriate amount of hydrazine, reflux at 100 ℃ for 24 h to proce black granular precipitation, filter and dry to obtain graphene. Sasha stankovich et al. Prepared graphene with a thickness of about 1 nm by chemical dispersion method
chemical dissociation method
chemical dissociation method is a method of preparing graphene from graphite oxide by thermal rection, and the oxygen-containing functional groups in the graphite oxide layers react at a certain temperature
one or more gaseous substances are introced into a reaction chamber for chemical reaction to proce a new material deposited on the substrate surface. The specific method is to decompose gaseous organic compounds containing carbon atoms such as methane (CH4) and acetylene (C2H2) on metal substrates such as nickel or copper at high temperature, and the carbon atoms with hydrogen atoms will be deposited and adsorbed on the metal surface to form graphene continuously
the gas is released rapidly, which makes the graphite oxide layer be reced and cleaved at the same time to get graphene. This is an important method to prepare graphene. Yang Quanhong of Tianjin University prepared high quality graphene by chemical dissociation of graphite oxide at low temperature.
8. Graphene era is to do graphene heating application procts, graphene era is very good, graphene heating film can also be made into graphene physiotherapy protective procts.
9. You can find your own graphene company to consult. For example, the graphene health instry company, Xianwang, is very good,
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