A graphitized carbon material and a method for producing the same

Abstract

This invention provides a graphitized carbon material and its preparation method. The preparation method includes the following steps: (1) adding a carbon-based polymer to the surface of a graphene material to obtain a composite film containing a graphene layer and a polymer layer; (2) graphitizing the composite film obtained in step (1) to obtain the graphitized carbon material; the graphene material includes at least one of untreated graphene, graphene treated with defects and / or heteroatoms. The preparation method provided by this invention, by introducing at least one of untreated graphene, graphene treated with defects and / or heteroatoms, can promote the graphitization of the carbon-based polymer, catalyzing the graphitization of the polymer layer from the inside out and / or from the outside in, so that the graphitized layer is uniformly distributed throughout the carbon material, giving the carbon material excellent thermal, mechanical and electrical properties, while reducing the graphitization temperature.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of material preparation, and particularly relates to a graphitized carbon material and a preparation method thereof. BACKGROUND

[0002] With the development of microelectronic devices towards miniaturization and high-density integration, signal transmission towards high frequency and high speed, the heat dissipation problem of electronic devices is becoming more and more important. It is reported that the heat dissipation of electronic devices in 5G is 3 times higher than that in 4G. Therefore, it is essential to develop efficient heat-conducting materials for high-power electronic devices and portable devices. Thin film carbon materials are widely used in various electronic devices due to their high thermal conductivity, electrical conductivity, mechanical strength and modulus. Compared with metal materials such as copper or aluminum, thin film carbon materials have lighter weight and are considered to be very promising heat-conducting materials. The increase of graphitization degree is beneficial to improve the thermal conductivity, electrical conductivity and anti-vibration performance of thin film carbon materials, therefore, the preparation of high-orientation thin film carbon materials is an important research direction.

[0003] Template method (including epitaxial growth on crystal substrate or seed crystal) is often used to prepare ordered materials, but there are few studies on the preparation of high-quality thin film carbon materials. The synthesis of thin film carbon materials usually requires the combination of high temperature and high pressure (highly oriented pyrolytic graphite, HOPG), for example, CN112813496A discloses a preparation method of highly oriented pyrolytic graphite, which comprises: first immersing a graphite substrate in a pretreatment liquid, taking it out and drying, then using chemical deposition method, passing in methane and nitrogen, obtaining pyrolytic graphite plate; when the pyrolytic graphite plate is cooled to 700-750℃, it is put into a magnetic field, and when the temperature is reduced to 100℃, it is taken out; the pyrolytic graphite plate treated by magnetic field is taken out and placed in a high-pressure high-temperature furnace, inert gas is passed in, and heat treatment is carried out. The invention improves the orientation degree of pyrolytic graphite by pretreating the graphite substrate and using chemical vapor deposition method to prepare pyrolytic graphite, but the pyrolysis temperature is high and the energy consumption is large.

[0004] Using chemical conversion method to promote the evolution of microstructure of carbon material is an important strategy for preparing high-quality thin film carbon material, and the key is to find a suitable catalyst and thin film material forming method.

[0005] For example, CN107601491A discloses a preparation method of three-dimensional graphitized carbon, comprising the following steps: mixing a water-soluble porous polymer and a catalyst in water, drying after reaction to obtain a first product; mixing the first product with KOH in an organic solvent, drying after reaction to obtain a second product; sequentially performing heating treatment and acid pickling on the second product to obtain three-dimensional graphitized carbon. The graphitized carbon material prepared by the above method is used for preparing positive active material and negative active material, improving the energy density and power density of lithium ion capacitor, having good cycle performance and high working voltage. However, the orientation degree of the graphitized carbon material is poor.

[0006] Therefore, it is an urgent problem to be solved in the field to find a suitable graphitization catalyst for the forming of thin film carbon material and to develop a suitable catalytic graphitization method to realize the preparation of high-quality graphitized thin film on a macro scale and to obtain thin film carbon material with greatly improved thermal and mechanical properties at a lower energy consumption. SUMMARY

[0007] In view of the deficiencies in the prior art, the purpose of the present application is to provide a graphitized carbon material and a preparation method thereof. The preparation method can catalytically graphitize the carbon-based polymer from the inside out and / or from the outside in by introducing at least one of untreated graphene, graphene subjected to defect treatment and / or graphene subjected to heteroatom treatment, so that the graphitized layer is uniformly distributed in the entire carbon material, and the mechanical, thermal and electrical properties of the thin film carbon material are improved at a lower energy consumption.

[0008] To achieve this purpose, the present application adopts the following technical solutions:

[0009] In a first aspect, the present application provides a preparation method of a graphitized carbon material, comprising the following steps:

[0010] (1) adding a carbon-based polymer to the surface of a graphene material to obtain a composite film comprising a graphene layer and a polymer layer;

[0011] (2) performing graphitization treatment on the composite film obtained in step (1) to obtain the graphitized carbon material; the graphene material comprises at least one of untreated graphene, graphene subjected to defect treatment and / or graphene subjected to heteroatom treatment.

[0012] In the present application, the preparation method can promote the graphitization of the carbon-based polymer by introducing at least one of untreated graphene, graphene subjected to defect treatment and / or graphene subjected to heteroatom treatment, and catalytically graphitize the polymer layer from the inside out and / or from the outside in, so that the graphitized layer is uniformly distributed in the entire carbon material, so that the carbon material has excellent thermal, mechanical and electrical properties, and the graphitization treatment temperature can be reduced.

[0013] Preferably, the graphene material comprises any one or a combination of at least two of CVD graphene, graphene oxide or exfoliated graphene, preferably CVD graphene and / or graphene oxide.

[0014] In the present application, the CVD graphene refers to graphene material grown on the surface of a substrate by chemical vapor deposition; the graphene oxide and exfoliated graphene are formed into films on the surface of a substrate in the form of a solution.

[0015] Preferably, the substrate comprises a metallic substrate or a non-metallic substrate.

[0016] Preferably, the material of the metallic substrate comprises any one or a combination of at least two of copper, iron, cobalt, nickel or platinum, preferably copper.

[0017] Preferably, the material of the non-metallic substrate comprises silicon oxide and mica sheet.

[0018] More preferably, the CVD graphene in the present application can increase the orientation degree of graphitized carbon in the carbon material, so that the carbon-based polymer is orderly oriented from inside to outside and / or from outside to inside, and the disordered arrangement thereof is reduced; the CVD graphene treated by defects and heteroatoms can further increase the ordered orientation degree of the graphitized carbon, and improve the mechanical, thermal and electrical properties of the carbon material; the small flake graphene, such as graphene oxide and exfoliated graphene, can also promote the graphitization of the carbon-based polymer, but the lattice arrangement of the graphitized carbon obtained is relatively disordered, resulting in slightly worse mechanical, thermal and electrical properties of the carbon material than the graphitized carbon material catalyzed by the CVD graphene. However, the graphene oxide and exfoliated graphene have the advantages of low cost and convenient processing, and also have practical application value.

[0019] Preferably, the defect treatment and / or heteroatom treatment comprises any one or a combination of at least two of chemical treatment, plasma treatment or ozone treatment, preferably ozone treatment.

[0020] In the present application, the chemical treatment can increase the degree of heteroatom functional groups and defects on the surface of graphene; the plasma treatment forms defects in the structure of graphene; and the ozone treatment can form defects in the structure of graphene and achieve oxygen doping and chemical modification.

[0021] Preferably, the method of the chemical treatment comprises any one or a combination of at least two of hydrothermal method, pyrolysis method or solution method.

[0022] Preferably, the reagent of the chemical treatment comprises any one or a combination of at least two of poly(oxypropylene)diamine, H2O2, NH3, urea or xenon difluoride.

[0023] Preferably, the plasma gas of the plasma treatment comprises any one or a combination of at least two of hydrogen, nitrogen, oxygen or argon.

[0024] Preferably, the plasma treatment is performed for a time period of 1-300 s, such as 1 s, 2 s, 4 s, 6 s, 8 s, 10 s, 15 s, 20 s, 25 s, 30 s, 35 s, 40 s, 45 s, 50 s, 55 s, 60 s, 70 s, 80 s, 90 s, 100 s, 120 s, 140 s, 160 s, 180 s, 200 s, 220 s, 240 s, 260 s, 280 s, 300 s, or the like, further preferably 10-50 s.

[0025] Preferably, the plasma treatment is performed at a power of 10-50 W, such as 10 W, 12 W, 14 W, 16 W, 18 W, 20 W, 22 W, 24 W, 26 W, 28 W, 30 W, 34 W, 38 W, 40 W, 42 W, 44 W, 46 W, 48 W, 50 W, or the like.

[0026] Preferably, the ozone treatment is performed using an ultraviolet ozone cleaner.

[0027] Preferably, the ozone treatment is performed for a time period of 1-15 min, such as 1 min, 2 min, 3 min, 4 min, 5 min, 6 min, 7 min, 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min, or the like, preferably 5-10 min.

[0028] Preferably, the graphene layer of step (1) has a thickness of 0.1-10 nm, such as 0.1 nm, 0.2 nm, 0.25 nm, 0.3 nm, 0.32 nm, 0.34 nm, 0.36 nm, 0.38 nm, 0.4 nm, 0.8 nm, 1 nm, 2 nm, 3 nm, 4 nm, 5 nm, 6 nm, 7 nm, 8 nm, 9 nm, 9.5 nm, 10 nm, or the like, preferably 0.3-1.0 nm.

[0029] Preferably, the carbon-based polymer comprises any one or a combination of at least two of polyacrylonitrile, polymethyl methacrylate, polyimide, polycarbonate, polyarylacetylene, polydivinylbenzene or polyvinyltriphenyl ethynyl silane, preferably polyacrylonitrile.

[0030] Preferably, the method of step (1) comprises at least one of coating, solid state lamination or liquid phase mixing, further preferably coating.

[0031] Preferably, the carbon-based polymer is coated in the form of a carbon-based polymer dispersion.

[0032] Preferably, the solvent of the carbon-based polymer dispersion includes N,N-dimethylformamide.

[0033] Preferably, the solid content of the carbon-based polymer dispersion is 1.0 to 10%, for example, it can be 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, etc.

[0034] Preferably, the coating method includes spin coating.

[0035] Preferably, the spin coating equipment is a centrifugal spin coater.

[0036] Preferably, the coating rotation speed is 1000-8000 r / min, for example, it can be 1000 r / min, 1500 r / min, 2000 r / min, 3000 r / min, 4000 r / min, 5000 r / min, 6000 r / min, 7000 r / min, 8000 r / min, etc.

[0037] Preferably, the coating time is 10 to 60 seconds, for example, 10 seconds, 20 seconds, 30 seconds, 40 seconds, 50 seconds, 55 seconds, 60 seconds, etc.

[0038] Preferably, the thickness of the polymer layer is 300-400 nm, for example, it can be 300 nm, 310 nm, 320 nm, 330 nm, 340 nm, 350 nm, 360 nm, 370 nm, 380 nm, 390 nm, 400 nm, etc.

[0039] Preferably, step (1) after obtaining the composite film further includes a step of removing the graphene material substrate.

[0040] Preferably, the method for removing the graphene material substrate includes removal by solution etching.

[0041] Preferably, the solute in the etching solution includes any one or a combination of at least two of ammonium persulfate, sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, ferric chloride, or ferric nitrate.

[0042] Preferably, the concentration of the etching solution is 0.1 to 1 mol / L, for example, it can be 0.1 mol / L, 0.2 mol / L, 0.4 mol / L, 0.6 mol / L, 0.8 mol / L, 1 mol / L, etc.

[0043] Preferably, the equipment for the graphitization process in step (2) includes a heating furnace.

[0044] Preferably, step (2) further includes a step of preheating the composite film before the graphitization treatment.

[0045] Preferably, the preheating temperature is 200-300℃, for example, it can be 200℃, 220℃, 240℃, 260℃, 280℃, 300℃, etc.

[0046] Preferably, the preheating time is 1-4h, for example, it can be 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, etc.

[0047] Preferably, the preheating is carried out in air atmosphere.

[0048] Preferably, the graphitization temperature in step (2) is 1000-3000℃, for example, it can be 1000℃, 1100℃, 1200℃, 1300℃, 1400℃, 1500℃, 1600℃, 1700℃, 1800℃, 2000℃, 2200℃, 2400℃, 2600℃, 2800℃, 3000℃, etc.

[0049] Preferably, the graphitization time in step (2) is 0.1-2h, for example, it can be 0.1h, 0.2h, 0.4h, 0.6h, 0.8h, 1h, 1.2h, 1.4h, 1.6h, 1.8h, 2h, etc.

[0050] Preferably, the atmosphere of the graphitization in step (2) is argon and / or hydrogen.

[0051] Preferably, the heating rate and the cooling rate of the graphitization in step (2) are each independently 4-10℃ / min, for example, it can be 4℃ / min, 4.2℃ / min, 4.4℃ / min, 4.8℃ / min, 5℃ / min, 5.2℃ / min, 5.4℃ / min, 5.8℃ / min, 6℃ / min, 6.5℃ / min, 7℃ / min, 7.5℃ / min, 8℃ / min, 8.5℃ / min, 9℃ / min, 9.5℃ / min, 10℃ / min, etc.

[0052] Preferably, the pressure of the graphitization in step (2) is 101.325kPa.

[0053] Preferably, the preparation method comprises the following steps:

[0054] (1) coating a carbon-based polymer on the surface of the graphene material to obtain a composite film comprising a graphene layer with a thickness of 0.1-10nm and a polymer layer with a thickness of 300-400nm;

[0055] (2) subjecting the composite film obtained in step (1) to graphitization treatment at a temperature of 1000-3000℃, and the graphitization treatment time is 0.1-2h, to obtain the graphitized carbon material.

[0056] The graphene material comprises at least one of untreated graphene, graphene treated by defect treatment and / or heteroatom treatment.

[0057] In a second aspect, the present application provides a graphitized carbon material prepared by the preparation method of the first aspect.

[0058] The numerical range of the present application includes not only the point values listed above, but also any point values between the above numerical ranges that are not listed, and the present application does not exhaustively list the specific point values included in the range for the sake of brevity and simplicity.

[0059] Compared with the prior art, the present application has the following beneficial effects:

[0060] The preparation method of the graphitized carbon material provided by the present application coats a carbon-based polymer on the surface of a graphene material, and then performs graphitization treatment. The graphene material acts as a catalyst for graphitization of the carbon-based polymer, and can perform graphitization on the carbon-based polymer layer from the inside to the outside and / or from the outside to the inside, so that the graphitized layer is uniformly distributed in the entire thin film carbon material. In addition, the orientation of the graphitized carbon layer is similar to that of the graphene layer, so that the mechanical, thermal and electrical properties of the obtained carbon material are greatly improved. BRIEF DESCRIPTION OF DRAWINGS

[0061] Figure 1 Raman spectrum of the graphitized carbon material obtained by the preparation method of the graphitized carbon material provided by the present application using Examples 1-6 and Comparative Example 1;

[0062] Figure 2 Transmission electron microscope image of the graphitized carbon material obtained by the preparation method of the graphitized carbon material provided by the present application using Example 7;

[0063] wherein, Figure 2 a is a transmission electron microscope image of a cross section of the graphitized carbon material; Figure 2 b is a transmission electron microscope image of a cross section of the graphitized carbon material under high resolution;

[0064] Figure 3 Transmission electron microscope image of the graphitized carbon material obtained by the preparation method of the graphitized carbon material provided by the present application using Comparative Example 2;

[0065] wherein, Figure 3 a is a transmission electron microscope image of a cross section of the graphitized carbon material; Figure 3 b is a transmission electron microscope image of a cross section of the graphitized carbon material under high resolution. DETAILED DESCRIPTION

[0066] The technical solutions of the present application are further illustrated below through specific embodiments. Those skilled in the art should understand that the embodiments are only used to help understand the present application and should not be regarded as specific limitations on the present application.

[0067] In the present application, the materials used in all examples and comparative examples are as follows:

[0068] Polyacrylonitrile: polyacrylonitrile was purchased from Shanghai Dibai Biotechnology Co., Ltd., AR grade;

[0069] CVD graphene: Meilunam Co., Ltd.

[0070] Graphene oxide: Hangzhou Gaolun Technology Co., Ltd.

[0071] Example 1

[0072] The present embodiment provides a preparation method of graphitized carbon material, which comprises the following steps:

[0073] (1) After the monolayer CVD graphene film (copper substrate as the base) is treated with ozone in a UV ozone cleaning machine for 10 min, a polyacrylonitrile dispersion solution (solid content 2%, solvent N,N-dimethylformamide) is spin-coated on the surface of the monolayer CVD graphene film after ozone treatment using a centrifugal homogenizer, the rotation speed is 3000 r / min, and the homogenization time is 30 s. After drying, the copper substrate is removed by etching with an ammonium persulfate solution with a concentration of 0.5 mol / L, to obtain a composite film comprising a graphene layer and a polyacrylonitrile layer;

[0074] (2) The composite film obtained in step (1) is picked up using a SiO2 / Si substrate and placed in a tube furnace, heated to 250℃ in air, and kept for 2 h. Subsequently, it is heated to 1500℃ at a heating rate of 5℃ / min in 50 sccm argon, kept for 30 min, and finally the tube furnace is cooled to room temperature at a cooling rate of 5℃ / min under the same gas flow, to obtain the graphitized carbon material.

[0075] The structure of the graphitized carbon material obtained in Example 1 is characterized by Raman spectroscopy (Raman, instrument model: Renishaw inVia plus), and the results are shown in Figure 1 The value of I D / I G of the graphitized carbon material obtained by the preparation method provided in Example 1 is about 0.552.

[0076] Example 2

[0077] The present embodiment provides a preparation method of graphitized carbon material, which is only different from Example 1 in that the ozone treatment time in step (1) is 5 min, and the other steps and parameters are the same as those in Example 1.

[0078] The structure of the graphitized carbon material obtained in Example 2 was characterized by Raman spectroscopy (Raman, instrument model: Renishaw inVia plus), and the results are shown in Figure 1 The value of I D / I G of the graphitized carbon material obtained using the preparation method provided in Example 2 was about 0.697.

[0079] Example 3

[0080] This example provides a preparation method of a graphitized carbon material, which is only different from Example 1 in that the ozone treatment in step (1) is replaced by argon plasma treatment, the power of the argon plasma treatment is 50 W, and the time is 20 s, and the other steps and parameters are the same as those in Example 1.

[0081] The structure of the graphitized carbon material obtained in Example 3 was characterized by Raman spectroscopy (Raman, instrument model: Renishaw inVia plus), and the results are shown in Figure 1 The value of I D / I G of the graphitized carbon material obtained using the preparation method provided in Example 3 was about 0.754.

[0082] Example 4

[0083] This example provides a preparation method of a graphitized carbon material, which is only different from Example 3 in that the time of the argon plasma treatment in step (1) is 50 s, and the other steps and parameters are the same as those in Example 3.

[0084] The structure of the graphitized carbon material obtained in Example 4 was characterized by Raman spectroscopy (Raman, instrument model: Renishaw inVia plus), and the results are shown in Figure 1 The value of I D / I G of the graphitized carbon material obtained using the preparation method provided in Example 4 was about 0.750.

[0085] Example 5

[0086] This example provides a preparation method of a graphitized carbon material, which is only different from Example 1 in that the ozone treatment in step (1) is replaced by oxygen plasma treatment, the power of the oxygen plasma treatment is 10 W, and the time is 10 s, and the other steps and parameters are the same as those in Example 1.

[0087] The structure of the graphitized carbon material obtained in Example 5 was characterized by Raman spectroscopy (Renishaw inVia plus instrument), and the results are as follows: Figure 1 As shown, the graphitized carbon material I obtained using the preparation method provided in Example 5 D / I G The value is approximately 0.763.

[0088] Example 6

[0089] This embodiment provides a method for preparing graphitized carbon materials. The only difference between this method and Example 1 is that the graphene material in step (1) is not subjected to defect treatment and / or heteroatom treatment, i.e., it is not subjected to ozone treatment. All other steps and parameters are the same as in Example 1.

[0090] The structure of the graphitized carbon material obtained in Example 6 was characterized by Raman spectroscopy (Renishaw inVia plus instrument), and the results are as follows: Figure 1 As shown, the graphitized carbon material I obtained using the preparation method provided in Example 6 D / I G The value is approximately 0.762.

[0091] Example 7

[0092] This embodiment provides a method for preparing graphitized carbon material. The only difference between this method and Example 6 is that the temperature is raised to 1000°C in argon gas in step (2). All other steps and parameters are the same as in Example 6.

[0093] The cross-sectional morphology of the graphitized carbon material obtained in Example 7 was characterized by transmission electron microscopy (TEM, instrument model: Tecnai G2 F20 U-TWIN), and the results are as follows: Figure 2 As shown, where, Figure 2 Image a is a transmission electron microscope (TEM) image of a cross-section of graphitized carbon material. Figure 2 b is a high-resolution transmission electron microscope image of the cross-section of graphitized carbon material; from Figure 2 a and Figure 2 As shown in b, lattice fringes appear in the carbon layer near graphene, and these lattice fringes are not entirely from the original graphene. This indicates that graphene materials can lower the graphitization temperature of materials, allowing graphitization to begin at low temperatures, i.e., 1000℃, thus changing the structure of the material and improving its performance.

[0094] Example 8

[0095] The embodiment provides a preparation method of graphitized carbon material, which is only different from the embodiment 1 in that the time of ozone treatment in step (1) is 15 min, and other steps and parameters are the same as those of the embodiment 1.

[0096] Embodiment 9

[0097] The embodiment provides a preparation method of graphitized carbon material, which is only different from the embodiment 3 in that the time of argon plasma treatment in step (1) is 80 s, and other steps and parameters are the same as those of the embodiment 3.

[0098] Embodiment 10

[0099] The embodiment provides a preparation method of graphitized carbon material, which is only different from the embodiment 3 in that the power of argon plasma treatment in step (1) is 80 W, and other steps and parameters are the same as those of the embodiment 3.

[0100] Embodiment 11

[0101] The embodiment provides a preparation method of graphitized carbon material, which is only different from the embodiment 6 in that the single-layer CVD graphene film is replaced by an oxidized graphene film with the same thickness in step (1), and other steps and parameters are the same as those of the embodiment 6; the oxidized graphene film is obtained by coating an oxidized graphene aqueous solution on a copper substrate and drying.

[0102] Comparative Example 1

[0103] The comparative example provides a preparation method of graphitized carbon material, which is only different from the embodiment 1 in that the polyacrylonitrile dispersion solution is directly spin-coated on the surface of the copper substrate in step (1), and other steps and parameters are the same as those of the embodiment 1.

[0104] The structure of the graphitized carbon material obtained in the comparative example 1 is characterized by a Raman spectrum (Raman, instrument model: Renishaw inVia plus), and the results are shown in Figure 1 The I D / I G of the graphitized carbon material obtained by the preparation method provided in the comparative example is about 0.942.

[0105] Comparative Example 2

[0106] The comparative example provides a preparation method of graphitized carbon material, which is only different from the comparative example 1 in that the temperature is increased to 1000 DEG C in argon in step (2), and other steps and parameters are the same as those of the comparative example 1.

[0107] The cross-sectional morphology of the graphitized carbon material obtained in the comparative example 2 is characterized by TEM, and the results are shown in Figure 3 Figure 3 ​a is a transmission electron microscope image of a cross-section of graphitized carbon material; Figure 3 b is a high-resolution transmission electron microscope image of the cross-section of graphitized carbon material, from... Figure 3 As shown in a and 3b, the contrast is uniform throughout the film, and there are no detectable lattice fringes. This indicates that when no graphene material is added, the temperature is too low at 1000℃, and the material cannot begin to graphitize, resulting in no significant changes in structure and properties.

[0108] Performance testing

[0109] (1)I D / I G The structures of the graphitized carbon materials obtained in Examples 1-11 and Comparative Examples 1 and 2 were characterized by Raman spectroscopy (Renishaw inVia plus). The intensity of the D peak (1300 cm⁻¹) in the Raman spectrum was measured. -1 Nearby, I D ) and G peak intensity (1580cm) -1 Nearby, I G The ratio of I to ) D / I G The smaller the value, the higher the degree of graphitization, the better the orientation, and the better the mechanical, thermal, and electrical properties of the graphitized carbon material.

[0110] (2) Electrical properties: In this invention, the thickness of the graphitized carbon material is 350±10nm, and the resistivity of the graphitized carbon material is obtained by four-probe method.

[0111] The specific test results are shown in Table 1:

[0112] Table 1

[0113]

[0114]

[0115] As shown in the table above, the method for preparing graphitized carbon materials provided by this invention, by introducing at least one of untreated graphene, defect-treated graphene, and / or heteroatom-treated graphene, can catalytically graphitize carbon-based polymers from the inside out or from the outside in, resulting in a uniformly distributed graphitized layer throughout the carbon material. This improves the mechanical, thermal, and electrical properties of the thin-film carbon material with lower energy consumption; the graphitized carbon material I obtained by the preparation method... D / I G The resistivity is 0.5 to 0.941, more preferably 0.5 to 0.77; the resistivity of the graphitized carbon material is 2.2 to 5.7 Ω·cm, more preferably 2.2 to 3.8 Ω·cm.

[0116] From the comparison of Example 1 and Example 8, it can be seen that when the time of the ozone treatment is not within the specific range, the I D / I G of the carbon material increases, and the resistivity increases; from the comparison of Example 3 and Example 9-10, it can be seen that when the time or power of the plasma treatment is not within the specific range, the I D / I G of the carbon material increases, and the resistivity increases; from the comparison of Example 6 and Example 11, it can be seen that compared with graphene oxide, the carbon material prepared from CVD graphene has better performance.

[0117] From the comparison of Example 1 and Comparative Example 1, it can be seen that when no graphene material is added in the preparation method, the carbon material obtained has poor performance.

[0118] From the comparison of Example 7 and Comparative Example 2, it can be seen that when graphene material is added in the preparation method, the graphitization can start at a lower temperature, and the resistivity is lower; when no graphene material is added, the structure of the material has no obvious change at a lower temperature, and the resistivity is higher, which shows that the preparation method provided in the application can reduce the graphitization temperature.

[0119] In summary, in the preparation method of the graphitized carbon material provided in the application, the untreated graphene, the defect-treated graphene and / or the heteroatom-treated graphene has a good low-temperature catalysis effect on the formation of the graphite structure in the polymer; compared with perfect graphene, various defect-treated graphene and / or heteroatom-treated graphene can reduce the I D / I G of the composite film; the defect-treated graphene treated by ozone has the most obvious promoting effect on the carbonization process of the polymer, and this promoting effect is further deepened with the increase of the defects in the graphene.

[0120] The applicant declares that the above description is only a specific embodiment of the application, but the protection scope of the application is not limited thereto, and those skilled in the art should understand that any changes or replacements within the technical scope disclosed in the application can be easily thought of by those skilled in the art, and all fall within the protection scope and disclosure scope of the application.

Claims

1. A method for producing a graphitized carbon material, characterized by, The preparation method comprises the following steps: (1) adding a carbon-based polymer on the surface of a graphene material to obtain a composite film comprising a graphene layer and a polymer layer; (2) performing graphitization treatment on the composite film obtained in step (1) to obtain the graphitized carbon material; The temperature of the graphitization treatment in step (2) is 1000-1500 ℃; The graphene material is CVD graphene subjected to defect treatment and / or heteroatom treatment.

2. The production method according to claim 1, characterized by, The defect treatment and / or heteroatom treatment comprises any one or a combination of at least two of a chemical method, a plasma treatment or an ozone treatment.

3. The production method according to claim 2, characterized by, The defect treatment and / or heteroatom treatment comprises ozone treatment.

4. The preparation method according to claim 2, characterized in that, The chemical method comprises any one or a combination of at least two of a hydrothermal method, a pyrolysis method or a solution method.

5. The preparation method according to claim 2, characterized in that, The reagent of the chemical treatment comprises any one or a combination of at least two of poly(oxypropylene)diamine, H2O2, NH3, urea or xenon difluoride.

6. The preparation method according to claim 2, characterized in that, The plasma gas of the plasma treatment comprises any one or a combination of at least two of hydrogen, nitrogen, oxygen or argon.

7. The preparation method according to claim 2, characterized in that, The time of the plasma treatment is 1-300 s.

8. The preparation method according to claim 7, characterized in that, The time of the plasma treatment is 10-50 s.

9. The preparation method according to claim 2, characterized in that, The power of the plasma treatment is 10-50 W.

10. The method of claim 2, wherein, The ozone treatment device is an ultraviolet ozone cleaning machine.

11. The method of claim 2, wherein, The time of the ozone treatment is 1-15 min.

12. The method of claim 11, wherein, The time of the ozone treatment is 5-10 min.

13. The method of claim 1, wherein, The thickness of the graphene layer in step (1) is 0.1-10 nm.

14. The method of claim 13, wherein, The thickness of the graphene layer in step (1) is 0.3-1.0 nm.

15. The method of claim 1, wherein, The carbon-based polymer comprises any one or a combination of at least two of polyacrylonitrile, polymethyl methacrylate, polyimide, polycarbonate, polyarylacetylene, polydivinylbenzene or polyvinyltriphenyl ethynyl silane.

16. The method of claim 15, wherein, The carbon-based polymer comprises polyacrylonitrile.

17. The method of claim 1, wherein, The method of the addition in step (1) comprises at least one of coating, solid-state bonding or liquid-phase mixing.

18. The method of claim 17, wherein, The method of the addition in step (1) comprises coating.

19. The method of claim 17, wherein, The carbon-based polymer is coated in the form of a carbon-based polymer dispersion liquid.

20. The method of claim 19, wherein, The solvent of the carbon-based polymer dispersion liquid comprises N,N-dimethylformamide.

21. The method of claim 19, wherein, The solid content of the carbon-based polymer dispersion liquid is 1.0-10%.

22. The method of claim 17, wherein, The method of the coating comprises spin coating.

23. The preparation method according to claim 17, characterized in that, The rotation speed of the coating is 1000-8000 r / min.

24. The method of claim 17, wherein, The time of the coating is 10-60 s.

25. The method of claim 1, wherein, The thickness of the polymer layer is 300-400 nm.

26. The method of claim 1, wherein, After obtaining the composite film in step (1), a step of removing a graphene material substrate is further included.

27. The method of claim 26, wherein, The method of removing the graphene material substrate comprises removal by a solution etching method.

28. The method of claim 27, wherein, The solute of the etching solution comprises any one or a combination of at least two of ammonium persulfate, sulfuric acid, hydrochloric acid, nitric acid, hydrofluoric acid, ferric chloride or ferric nitrate.

29. The preparation method according to claim 27, characterized in that, The concentration of the etching solution is 0.1-1 mol / L.

30. The method of claim 1, wherein, The time of the graphitization treatment in step (2) is 0.1-2 h.

31. The method of claim 1, wherein, The atmosphere of the graphitization treatment in step (2) is argon and / or hydrogen.

32. The method of claim 1, wherein, The heating rate and the cooling rate of the graphitization treatment in step (2) are each independently 4-10 ℃ / min.

33. The method of claim 1, wherein, The pressure of the graphitization treatment in step (2) is 101.325 kPa.

34. The method of claim 1, wherein, The preparation method comprises the following steps: (1) adding a carbon-based polymer on the surface of a graphene material to obtain a composite film comprising a graphene layer with a thickness of 0.1-10 nm and a polymer layer with a thickness of 300-400 nm; (2) performing graphitization treatment on the composite film obtained in step (1) at a temperature of 1000-1500 ℃, and the graphitization treatment time is 0.1-2 h to obtain the graphitized carbon material; The graphene material is a CVD graphene subjected to a defect treatment and / or a heteroatom treatment.

35. A graphitized carbon material characterized in that, The graphitized carbon material is prepared by the preparation method according to any one of claims 1-34.

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