CN113321208B - Preparation method of high-compactness graphene film - Google Patents
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 221
- 229910021389 graphene Inorganic materials 0.000 title claims abstract description 191
- 238000002360 preparation method Methods 0.000 title claims abstract description 10
- 239000002002 slurry Substances 0.000 claims abstract description 38
- 238000000034 method Methods 0.000 claims abstract description 32
- 238000011282 treatment Methods 0.000 claims abstract description 26
- 238000005087 graphitization Methods 0.000 claims abstract description 18
- 239000002243 precursor Substances 0.000 claims abstract description 12
- 238000010438 heat treatment Methods 0.000 claims description 19
- 230000008569 process Effects 0.000 claims description 18
- 238000000967 suction filtration Methods 0.000 claims description 10
- 125000004432 carbon atom Chemical group C* 0.000 claims description 8
- 230000001681 protective effect Effects 0.000 claims description 5
- 238000007581 slurry coating method Methods 0.000 claims description 3
- 230000009467 reduction Effects 0.000 abstract description 23
- 239000011148 porous material Substances 0.000 abstract description 8
- 239000000126 substance Substances 0.000 abstract description 4
- 238000011049 filling Methods 0.000 abstract description 3
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract 2
- 229910002804 graphite Inorganic materials 0.000 description 29
- 239000010439 graphite Substances 0.000 description 29
- 238000011068 loading method Methods 0.000 description 12
- 238000005303 weighing Methods 0.000 description 12
- 239000002245 particle Substances 0.000 description 8
- 230000009471 action Effects 0.000 description 7
- 238000011946 reduction process Methods 0.000 description 7
- 239000012528 membrane Substances 0.000 description 6
- BFKJFAAPBSQJPD-UHFFFAOYSA-N tetrafluoroethene Chemical group FC(F)=C(F)F BFKJFAAPBSQJPD-UHFFFAOYSA-N 0.000 description 6
- 239000002131 composite material Substances 0.000 description 5
- 238000007598 dipping method Methods 0.000 description 5
- 238000005470 impregnation Methods 0.000 description 5
- 238000000280 densification Methods 0.000 description 4
- 238000007731 hot pressing Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 239000007789 gas Substances 0.000 description 3
- 230000017525 heat dissipation Effects 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 229910021383 artificial graphite Inorganic materials 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 125000004430 oxygen atom Chemical group O* 0.000 description 2
- 239000011343 solid material Substances 0.000 description 2
- 238000002441 X-ray diffraction Methods 0.000 description 1
- 238000009825 accumulation Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 150000001721 carbon Chemical group 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 239000004020 conductor Substances 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000007888 film coating Substances 0.000 description 1
- 238000009501 film coating Methods 0.000 description 1
- 230000008595 infiltration Effects 0.000 description 1
- 238000001764 infiltration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000000465 moulding Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 230000000704 physical effect Effects 0.000 description 1
- 230000008092 positive effect Effects 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/15—Nano-sized carbon materials
- C01B32/182—Graphene
- C01B32/184—Preparation
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B2204/00—Structure or properties of graphene
- C01B2204/20—Graphene characterized by its properties
- C01B2204/24—Thermal properties
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Abstract
The invention discloses a preparation method of a high-compactness graphene film, which uses graphene oxide water slurry A as a film forming precursor and uses graphene oxide water slurry B as an impregnant. Assembling a graphene film by a wet chemical method, performing thermal reduction, filling an impregnant into the pores of the reduced graphene oxide, repeating for a plurality of times until a compact product is obtained, and finally completing graphitization treatment on the compact thermal reduction product. The graphene film obtained by the method has fewer pores and high compactness, so that the graphene film has higher thermal conductivity. Can be used in the fields of transverse temperature equalization and the like of electronic equipment.
Description
Technical Field
The invention belongs to the technical field of graphene film preparation, and particularly relates to a preparation method of a high-compactness graphene film.
Background
The rapid development of integrated circuits has made heat dissipation of electronic devices a common problem. Taking a smart phone as an example, the peak power consumption of the smart phone in the 5G era can reach more than 10W. Heat accumulation is extremely easy to form in high power parts such as a Central Processing Unit (CPU) and a baseband chip. If the heat at these locations cannot be removed by effective means, localized hot spots will be created, which in turn affect the performance and lifetime of the device. The graphite has extremely high planar heat conducting capacity, and the characteristic is very favorable for transverse uniform temperature of local heat, so that the artificial graphite film is widely used as a heat radiating material in electronic products such as smart phones and the like. The technical principle is that the graphite film diffuses local heat to the whole large plane in a heat conduction mode, so that the heat flow density is reduced, and local hot spots are eliminated. The heat expansion capability of the graphite film in the process is directly related to the thermal conductivity of the artificial graphite film.
Graphene is a graphite crystal with a hexagonal honeycomb structure, and the theoretical thermal conductivity of the graphene can reach more than 3000W/mK. Once the graphene is assembled into a graphene film with a certain thickness, the graphene film can be used as a new generation of heat dissipation material. The main preparation method of the graphene comprises the technical routes of vapor deposition, graphene oxide and the like. The graphene oxide technical raw materials are cheap and easy to obtain, the process is mature, the industrialization is the most easy technical route, graphene oxide slurry is used as a precursor, graphene oxide is assembled into a GO film, and then the heat-conducting graphene film is obtained through technologies such as high-temperature reduction.
The heat dissipation capacity of a graphene film is directly related to its thermal conductivity (λ). The development of graphene films of high thermal conductivity is therefore a consensus among many engineering technicians. Graphene films are prepared via graphene oxide technology routes, most of which are subjected to reduction techniques to remove non-carbon atoms in the graphene oxide. The high-temperature thermal reduction can remove oxygen atoms in graphene oxide and repair hexagonal carbon atom surface networks, and is an important technical route for preparing graphene films. The removal of these non-carbon atoms necessarily leaves defects in the graphene film, particularly high temperature thermal reduction techniques, where the evolved gases are very prone to forming pores within the film under the action of high temperature. The oxygen content in the oxidized graphene is generally about 40%, so that in the actual production process, the volume density of the graphene film formed by high-temperature thermal reduction is generally low (lower than 0.5 g/cm) 3 ). The thermal conductivity of a solid material is directly related to the bulk density. If the volume density is too low, this means that pores are contained inside the solid. These voids are poor conductors of heat. Therefore, improving the densification degree of the graphene film has a positive effect on obtaining the high-heat-conductivity graphene film.
Graphene oxide will undergo a series of chemical, physical changes during thermal reduction and high temperature heat treatment: in the thermal reduction process, oxygen atoms and other non-carbon elements are removed, the plane size is shrunk, and the thickness direction is also shrunk; during further high temperature heat treatment, the escaping gas causes expansion in the thickness direction under the effect of the high temperature. This complex physical change makes densification of the preparation of graphene films a difficulty in the industry. Chinese patent CN107010618A discloses a method for preparing a graphene film with high thermal conductivity, which is to treat a graphene oxide film by means of low-temperature hot pressing and high-temperature thermal reduction. Chinese patent CN107140619a further uses a high-temperature hot-pressing process to treat the graphene oxide film, and converts the graphene oxide film into a graphene film with high thermal conductivity under the combined action of high temperature and pressure. Most of the inventions relate to low temperature/medium temperature/high temperature hot pressure processes, and it must be pointed out that these methods have two disadvantages: as described above, graphene oxide undergoes shrinkage (in the planar direction) and expansion (in the thickness direction) during thermal reduction and thermal treatment. This complex dimensional change presents challenges to the manufacturing process. The principle of the hot press molding is to apply mechanical pressure to the sample by working up and down, so that the hot press process is effective for restraining expansion in the thickness direction. For such complicated dimensional changes of graphene oxide, it is not suitable to perform only the autoclave treatment. For example: the sample is subjected to compression treatment during the shrinkage stage, shrinkage of the sample is limited, and cracking is extremely easy to occur. Secondly, the cost of the hot pressing equipment is high, and the size of the product is limited by the working surface of the hot pressing machine.
Disclosure of Invention
Aiming at the technical defects existing in the prior art, the invention provides a densification method of a high-densification graphene film according to chemical and physical changes of graphene oxide in a heat treatment process. Namely, a graphene slurry for film formation and a graphene slurry for impregnation are prepared by the dimensional relationship between graphene particles. The former is used for suction filtration and film coating, and after the graphene oxide film is thermally reduced, the impregnated graphene slurry is used for filling the pores of the former. The impregnated product is subjected to thermal reduction, and the thermal reduction, the impregnation and the thermal reduction are repeated for a plurality of times, so that the high compactness (volume density is higher than 1.6 g/cm) is finally obtained 3 ) Is a graphene film of (a).
In order to achieve the technical purpose, the invention adopts the following technical scheme:
the preparation method of the high-compactness graphene film comprises the following steps:
1) Preparing a graphene oxide film by taking graphene oxide slurry A as a precursor through a suction filtration or slurry coating mode;
2) Thermally reducing the graphene oxide film in vacuum or inert atmosphere to remove non-carbon atoms;
3) Immersing the reduced graphene oxide film into graphene oxide slurry B, and vacuumizing to 10Kpa to complete the immersing process;
4) Repeating steps 2) and 3) until the weight and bulk density of the reduced graphene oxide film are no longer increased;
5) And heating the immersed graphene film in a protective atmosphere to finish graphitization treatment, and finally forming a compact graphene film.
The mass concentration of the graphene oxide in the graphene oxide slurry A is 1-6wt%, and the sheet diameter is 2-100 micrometers.
The mass concentration of the graphene oxide in the graphene oxide slurry B is 0.2-6 wt%, and the sheet diameter is 20-500 nanometers.
The graphene oxide slurry A is assembled into a graphene oxide film with the thickness of 10-400 micrometers through the modes of suction filtration, coating and the like.
The graphene oxide film is thermally reduced to be heated to 200-900 ℃ at a speed of 1 ℃/min.
The graphitization is to heat the reduced graphene oxide film to 2200-3100 ℃ at a speed of 5 ℃/min under a protective atmosphere, so as to form a compact graphene film.
The beneficial effects of the invention are as follows:
according to the invention, the graphene oxide film subjected to thermal reduction is filled with the impregnated graphene slurry, non-carbon atoms of the large-size graphene oxide film are removed in the thermal reduction process to leave pores, and the density of the graphene film is gradually improved in the repeated infiltration-thermal reduction process by filling the graphene oxide film with small size, so that the pores in the graphene film are correspondingly reduced, and the thermal conductivity of the solid material is improved.
Drawings
FIG. 1 is a process flow of preparing a high-density graphene oxide film according to the invention;
FIG. 2 is a scanning electron microscope photograph of a dense graphene film after repeated infiltration and thermal reduction of the present invention;
fig. 3 is an X-ray diffraction pattern of a high density graphene film in example 5 of the present invention.
Detailed Description
The following description of the present invention will be made more complete and clear in view of the detailed description of the invention, which is to be taken in conjunction with the accompanying drawings that illustrate only some, but not all, of the embodiments of the invention. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
The graphene oxide film is assembled by a wet chemical method by taking graphene oxide as a precursor. And obtaining the graphene film through a high-temperature thermal reduction mode. This process is accompanied by the removal of large amounts of non-carbon atoms and the formation of evolved gases. Therefore, the prepared graphene film often has pores, is difficult to compact, and further affects the electric conductivity and the heat conductivity of the graphene film. According to the invention, proper graphene oxide slurry is selected as a film forming component (A) and an impregnating component (B), and graphene oxide is firstly assembled into a film, and then is subjected to thermal reduction to remove non-carbon atoms. The reduced product is then impregnated with graphene oxide slurry B, which in turn thermally reduces the product. This process is repeated multiple times until weight gain is no longer gained, and the product is subsequently graphitized. The graphene oxide film is converted into high density (volume density is more than or equal to 1.6 g/cm) by the technology 3 ) Is a graphene film of (a).
As shown in fig. 1, the invention provides a preparation method of a high-compactness graphene film, which comprises the following steps:
1) Preparing a graphene oxide film with the mass concentration of 0.2-6 wt.% by using graphene oxide slurry A as a precursor in a suction filtration or slurry coating mode, wherein the graphene oxide film has the particle diameter of 2-100 microns;
2) Heating to 200-900 ℃ at a speed of 1 ℃/min in vacuum or inert atmosphere to thermally reduce the graphene oxide film, and removing non-carbon atoms;
3) Immersing the reduced graphene oxide film into graphene oxide slurry B with the mass concentration of 0.2-6 wt.%, and vacuumizing to complete the immersing process, wherein the diameter of graphene oxide sheets in the graphene oxide slurry B is 20-500 nanometers;
4) Repeating steps 2) and 3) until the weight and bulk density of the reduced graphene oxide film are no longer increased (fig. 2);
5) And heating the immersed graphene film to 2200-3100 ℃ at a speed of 5 ℃/min under a protective atmosphere to finish graphitization treatment, and finally forming a compact graphene film.
Example 1
1) And (3) taking graphene oxide slurry A with the average sheet diameter of 2 microns and the mass concentration of 1.0wt.% as a precursor, and forming a graphene oxide film with the thickness of 10 microns on the tetrafluoroethylene filter membrane by a vacuum suction filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 1 graphene oxide film was charged into a graphite mold, and then heated to 200 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) And taking the reduced graphene oxide film subjected to the thermal reduction treatment out of the die, and immersing the reduced graphene oxide film into graphene oxide slurry B with the average particle size of 20nm and the mass concentration of 0.2 wt.%. And vacuumizing the two in a vacuum oven to 10Kpa, and completing the dipping process under the action of negative pressure.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 200 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
6) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 2200 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.6g/cm 3 The thermal conductivity was 733W/mK.
Example 2
1) And (3) taking graphene oxide slurry A with the average sheet diameter of 10 micrometers and the mass concentration of 2.0wt.% as a precursor, and forming a graphene oxide film with the thickness of 20 micrometers on the tetrafluoroethylene filter membrane by a vacuum suction filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 2 graphene oxide films were loaded into a graphite mold and then heated to 400 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) The reduced graphene oxide film after the thermal reduction treatment was taken out of the mold and immersed in graphene oxide slurry B having an average particle diameter of 50nm and a mass concentration of 0.5 wt.%. And vacuumizing the two in a vacuum oven to 10Kpa, and completing the dipping process under the action of negative pressure.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 400 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes. The thermally reduced composite was again impregnated with graphene oxide slurry B and reduced again at 400 ℃ for 30 minutes.
6) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating to 2300 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.65g/cm 3 The thermal conductivity was 751W/mK.
Example 3
1) And (3) taking graphene oxide slurry A with the average sheet diameter of 20 micrometers and the mass concentration of 2.0wt.% as a precursor, and forming a graphene oxide film with the thickness of 50 micrometers on the tetrafluoroethylene filter membrane by a vacuum suction filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 2 graphene oxide films were loaded into a graphite mold and then heated to 600 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) The reduced graphene oxide film after the thermal reduction treatment was taken out of the mold and immersed in graphene oxide slurry B having an average particle diameter of 100nm and a mass concentration of 1.0 wt.%. And vacuumizing the two in a vacuum oven to 10Kpa, and completing the dipping process under the action of negative pressure.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating to 600 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes. The thermally reduced composite was again impregnated with graphene oxide slurry B and reduced again at 600 ℃ for 30 minutes, i.e., the impregnation-thermal reduction process was repeated 2 times.
6) And taking out the reduced graphene oxide film after the impregnation treatment, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating to 2400 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.71g/cm 3 The thermal conductivity was 779W/mK.
Example 4
1) And (3) taking graphene oxide slurry A with the average sheet diameter of 50 micrometers and the mass concentration of 3.0wt.% as a precursor, and forming a graphene oxide film with the thickness of 100 micrometers on the tetrafluoroethylene filter membrane by a vacuum suction filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 3 graphene oxide films were loaded into a graphite mold and then heated to 800 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) And taking the reduced graphene oxide film subjected to the thermal reduction treatment out of the die, and immersing the reduced graphene oxide film into graphene oxide slurry B with the average particle size of 200nm and the mass concentration of 2.0 wt.%. And vacuumizing the two in a vacuum oven to 10Kpa, and completing the dipping process under the action of negative pressure.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating to 800 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes. The thermally reduced composite was again impregnated with graphene oxide slurry B and was again reduced at 800 ℃ for 30 minutes, i.e., the impregnation-thermal reduction process was repeated 2 times.
6) And taking out the reduced graphene oxide film after the impregnation treatment, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating to 2500 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.79g/cm 3 The thermal conductivity was 811W/mK.
Example 5
1) And forming a graphene oxide film with the thickness of 200 microns on the tetrafluoroethylene filter membrane by using the graphene oxide slurry A with the average sheet diameter of 100 microns and the mass concentration of 5.0wt.% as a precursor through a vacuum filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 3 graphene oxide films were loaded into a graphite mold and then heated to 900 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) The reduced graphene oxide film after the thermal reduction treatment was taken out of the mold and immersed in graphene oxide slurry B having an average particle diameter of 500nm and a mass concentration of 3.0 wt.%. And vacuumizing the two in a vacuum oven to 10Kpa, and completing the dipping process under the action of negative pressure.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 900 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes. Re-impregnating the thermally reduced composite with graphene oxide slurry B and re-reducing at 900 ℃ for 30 minutes, i.e. repeating the impregnation-thermal reduction process 2 times
6) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 2600 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.85g/cm 3 The thermal conductivity was 835W/mK.
As shown in fig. 3, the characteristic size l=150 nm of the internal graphite crystallites can be calculated by the scherrer equation.
Example 6
1) And (3) taking graphene oxide slurry A with the average sheet diameter of 100 micrometers and the mass concentration of 6.0wt.% as a precursor, and forming a graphene oxide film with the thickness of 400 micrometers on the tetrafluoroethylene filter membrane by a vacuum suction filtration method.
2) The graphene oxide film was turned out and cut into squares of 100×100 mm. 3 graphene oxide films were loaded into a graphite mold and then heated to 900 ℃ at a rate of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes.
4) The reduced graphene oxide film after the thermal reduction treatment was taken out of the mold and immersed in graphene oxide slurry B having an average particle diameter of 500nm and a mass concentration of 6.0 wt.%. And putting the two materials into an autoclave, and pressurizing to 3MPa to finish the impregnation process.
5) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the graphite mold to 900 ℃ at a speed of 1 ℃/min. After reaching the target temperature, the temperature was kept for 30 minutes. Re-impregnating the thermally reduced composite with graphene oxide slurry B and re-reducing at 900 ℃ for 30 minutes, i.e. repeating the impregnation-thermal reduction process 2 times
6) And taking out the impregnated reduced graphene oxide film, weighing, loading the weighed reduced graphene oxide film into a graphite mold, and then heating the weighed reduced graphene oxide film to 3100 ℃ at a speed of 5 ℃/min. After reaching the target temperature, the temperature is kept for 30 minutes, and the graphitization treatment is completed. The volume density of the graphene film after graphitization treatment can reach 1.84g/cm 3 The thermal conductivity was 896W/mK.
The properties of the graphene films prepared in examples 1 to 6 of the present invention are shown in table 1.
Table 1 shows the physical properties of the ultra-high thermal conductivity graphene film
Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined in the appended claims and their equivalents.
Claims (1)
1. The preparation method of the high-compactness graphene film is characterized by comprising the following steps of:
1) Preparing a graphene oxide film by taking graphene oxide slurry A as a precursor through a suction filtration or slurry coating mode; the mass concentration of graphene oxide in the graphene oxide slurry A is 1-6wt%, and the sheet diameter is 2-100 micrometers;
2) Thermally reducing the graphene oxide film in vacuum or inert atmosphere to remove non-carbon atoms; the graphene oxide film is thermally reduced to be heated to 200-900 ℃ at a speed of 1 ℃/min;
3) Immersing the reduced graphene oxide film into graphene oxide slurry B, and vacuumizing to 10kPa to finish the immersing process; the mass concentration of graphene oxide in the graphene oxide slurry B is 0.2-6 wt%, and the sheet diameter is 20-500 nanometers;
4) Repeating steps 2) and 3) until the weight and bulk density of the reduced graphene oxide film are no longer increased;
5) Heating the immersed graphene film in a protective atmosphere to finish graphitization treatment, and finally forming a compact graphene film; the graphitization is to heat the reduced graphene oxide film to 2200-3100 ℃ at a speed of 5 ℃/min under a protective atmosphere.
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| CN115010119B (en) * | 2022-06-10 | 2023-10-20 | 中国航发北京航空材料研究院 | Graphene thick film and preparation method thereof |
| CN115536018B (en) * | 2022-09-30 | 2024-05-07 | 深圳市贝特瑞新能源技术研究院有限公司 | Graphene oxide slurry, heat conducting film and preparation method |
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130133373A (en) * | 2012-05-29 | 2013-12-09 | 한국과학기술원 | Fabricating method of graphene film for enhancing transparency and electrical characteristics based on ionic bond of self-assembled monolayer and large flake graphene oxide |
| CN108910863A (en) * | 2018-06-26 | 2018-11-30 | 中科钢研节能科技有限公司 | A kind of intelligence graphene heat conducting film and preparation method thereof |
| CN110077048A (en) * | 2019-05-16 | 2019-08-02 | 重庆云天化瀚恩新材料开发有限公司 | A kind of graphene heat-conducting piece and preparation method thereof |
| CN111232962A (en) * | 2020-01-17 | 2020-06-05 | 深圳垒石热管理技术有限公司 | Method for preparing ultra-thick graphene heat dissipation film |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2011159922A2 (en) * | 2010-06-16 | 2011-12-22 | The Research Foundation Of State University Of New York | Graphene films and methods of making thereof |
| WO2015061327A1 (en) * | 2013-10-21 | 2015-04-30 | The Penn State Research Foundation | Method for preparing graphene oxide films and fibers |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20130133373A (en) * | 2012-05-29 | 2013-12-09 | 한국과학기술원 | Fabricating method of graphene film for enhancing transparency and electrical characteristics based on ionic bond of self-assembled monolayer and large flake graphene oxide |
| CN108910863A (en) * | 2018-06-26 | 2018-11-30 | 中科钢研节能科技有限公司 | A kind of intelligence graphene heat conducting film and preparation method thereof |
| CN110077048A (en) * | 2019-05-16 | 2019-08-02 | 重庆云天化瀚恩新材料开发有限公司 | A kind of graphene heat-conducting piece and preparation method thereof |
| CN111232962A (en) * | 2020-01-17 | 2020-06-05 | 深圳垒石热管理技术有限公司 | Method for preparing ultra-thick graphene heat dissipation film |
Non-Patent Citations (1)
| Title |
|---|
| C/C复合材料孔隙结构的研究进展;樊凯;《材料导报》;20190627;第33卷(第7期);全文 * |
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