An integrated integrated carbonaceous honeycomb architecture material and a preparation method thereof

Abstract

An integrated carbon honeycomb structure material and its preparation method are disclosed, belonging to the field of carbon materials technology. Based on a co-sacrificial template low-temperature pyrolysis strategy, the target material can be obtained through three main steps: preparation of a metal salt-colloidal microsphere template precursor, precursor pressing and molding, and subsequent calcination and carbonization. This technology has the characteristics and advantages of simple preparation process, regular and controllable macroscopic structure of the sample (such as shape, area, and thickness), rich and tunable chemical composition, and three-dimensional interconnection of graphene carbon matrix. It has great application potential in many fields such as electrochemical energy storage, catalysis, gas separation, adsorption, and electromagnetic shielding.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of carbon materials, in particular to an integrated carbon honeycomb architecture material and a preparation method thereof. BACKGROUND

[0002] Among various carbon materials, high-crystallinity nanoporous (graphene-like) carbon materials have high specific surface area, developed pore structure, high electrical conductivity, and easily controllable physical and chemical properties, and are widely used in electrochemical energy storage, catalysis, gas separation, adsorption, electromagnetic shielding, and many other fields. Among them, nanoporous carbon materials with honeycomb structure formed based on the template method can realize more efficient mass transfer due to their highly regular and three-dimensionally ordered nanopore channel structure, thus exhibiting more excellent physical and chemical properties and further realizing more specific functional applications. In particular, regarding the application of porous carbon materials in the fields of electrochemical energy storage and catalysis: (1) Chen Zhongwei's group used a hard template method to prepare three-dimensionally interconnected ordered mesoporous materials, which as a framework showed excellent electrocatalytic performance in oxygen reduction reaction [Nano Energy 115 (2023) 108672]; (2) the inventor's team developed a graphene-like carbon material with three-dimensionally ordered macroporous structure (patent number: CN201610565108.4) in previous studies, which showed good performance whether used as a lithium ion battery anode or as a hydrogen evolution reaction electrocatalyst; (3) the inventor's team further developed an aluminum-based lithium metal anode material with carbon honeycomb architecture (patent number: CN202310665489.3) based on this technology, and the prepared carbon support material can achieve excellent lithium loading effect due to its excellent composition and structure; and the like. However, the ordered porous carbon materials prepared by existing researches are basically in the form of irregularly structured powders or small particles on a macroscopic scale [Cell Reports Physical Science 4 (2023) 101283], and further bonding and processing technology is needed to realize their application. The non-continuity on a large scale also greatly limits the above-mentioned structure-activity advantages of the ordered pore channel structure. Therefore, the present application proposes an integrated carbon honeycomb architecture material and a preparation method thereof, which can easily realize the preparation of three-dimensionally ordered macroporous carbon materials with regular macroscopic structure and centimeter-scale (and above) size, and is expected to play an important role in multiple fields (such as promoting the technical development of the next generation of high-specific-capacity high-safety secondary batteries as a high-quality host material for lithium, sodium, sulfur, silicon, and other high-specific-capacity electrode materials). So far, there is no literature report on integrated carbon honeycomb architecture materials and related preparation technologies. SUMMARY

[0003] The purpose of this invention is to provide an integrated carbon honeycomb structure material and its preparation method. Based on a co-sacrificial template low-temperature pyrolysis strategy, the integrated carbon honeycomb structure material can be obtained through three main steps: preparation of a metal salt-colloidal microsphere template precursor, precursor pressing and molding, and subsequent calcination and carbonization. This method has the advantages of simple preparation process, regular and controllable macroscopic structure of the sample (such as shape and thickness), rich and tunable chemical composition, and three-dimensional interconnection of graphene carbon matrix. Furthermore, the pore walls used to construct the honeycomb microstructure are made of graphene carbon matrix inlaid with metals or metal compounds.

[0004] Therefore, this invention provides an integrated carbon honeycomb structure material. This integrated material is assembled from a three-dimensional ordered macroporous carbon material as a matrix framework. The chemical composition of the target material can be controlled by adjusting the calcination temperature, time, atmosphere, and heating program. The macropore size of the target material can be controlled by adjusting the size of the microspheres in the colloidal microsphere template used (such as a polymethyl methacrylate (PMMA) template; for the synthesis method, see Inorg. Chem. 48 (2009) 4421-4434). Furthermore, given a mold (i.e., the shape and area of ​​the mold are fixed), the thickness of the target material can be controlled by adjusting the amount of precursor and the applied pressure. The resulting integrated carbon honeycomb structure material has structural characteristics such as large geometric dimensions, regular shape, highly ordered interconnection of a three-dimensional conductive network, high porosity, and large specific surface area.

[0005] This invention provides a method for preparing an integrated carbon honeycomb structure material, comprising the following steps:

[0006] (1) Prepare a solution by mixing a complexing agent (such as citric acid) and a metal salt (such as zinc nitrate, nickel nitrate, aluminum nitrate, iron nitrate and other nitrates) in a certain proportion as a precursor impregnation solution;

[0007] (2) The organic colloidal microsphere template (such as PMMA microsphere template, which has a mature synthesis method and is a non-patented technology) with irregular block or small particle shape is fully impregnated in the above precursor solution, filtered and dried to obtain the primary precursor.

[0008] (3) Weigh the primary precursor from step (2), place it in a mold for tableting, and hold it under a certain pressure for a period of time to obtain a block-shaped precursor with the shape of the mold. In particular, this invention uses a commercial infrared tablet press as an example to carry out this operation, and the diameter of the cylindrical mold used is 15.4 mm.

[0009] (4) The precursor pressed in step (3) is placed in a tube furnace and calcined at a set temperature under a specific atmosphere for a period of time. After calcination, it is cooled to room temperature to obtain an integrated carbon honeycomb structure material with a macroscopic mold shape. The honeycomb structure pore walls are graphene carbon matrix that can be inlaid with metals and / or metal compounds.

[0010] Furthermore, the concentration of citric acid complexing agent in the precursor solution prepared in step (1) of the present invention is 0.5–2 mol / L, preferably 1 mol / L.

[0011] Furthermore, the concentration of the metal salt in the precursor solution prepared in step (1) of the present invention is 1–3 mol / L, preferably 2 mol / L.

[0012] Furthermore, the immersion conditions described in step (2) of the present invention are immersion at room temperature for 3–16 hours, preferably immersion at room temperature for 12 hours.

[0013] Furthermore, in step (3) of the present invention, the mass of the precursor is 60–200 mg, preferably 120 mg; the applied pressure is 4–10 MPa, preferably 6 MPa; and the pressure holding time is 10–60 s, preferably 30 s.

[0014] Furthermore, in step (4) of the present invention, the target calcination temperature is 350–1200℃; the heating rate is 1–30℃ / min, preferably 4℃ / min; the reaction atmosphere is nitrogen, argon or a hydrogen-argon mixture; the gas flow rate is 1–500 sccm, preferably 200 sccm; and the holding time is 0–2h, preferably 30min.

[0015] The metal compounds mentioned are metal oxides, metal carbides, etc. The graphene carbonaceous material mentioned is pure graphene-like carbon, graphene-like carbon with low graphitization degree, graphene-like carbon rich in defects, etc.

[0016] Furthermore, if a cylindrical mold is used in step (3) of the present invention, the target material obtained in step (4) is an integrated carbon honeycomb structure material with a circular shape and uniform thickness, with a thickness of several hundred nanometers to millimeters, preferably 100–500 micrometers; its area is determined by the specific mold size and is in principle unlimited.

[0017] The preparation method provided by this invention has the following beneficial effects:

[0018] This invention provides a method for preparing an integrated carbon honeycomb structure material. Based on a low-temperature pyrolysis strategy using a co-sacrificial template (causing the material at the center of the template to calcine and evaporate, while the material in contact with the metal salt filling the template voids forms corresponding graphene carbon, which then bonds the corresponding metal or metal compound together), the method involves three main steps: preparation of a metal salt-colloidal microsphere template precursor, precursor pressing, and subsequent calcination and carbonization. This allows for the preparation of a target integrated carbon honeycomb structure material with a regular shape and uniform thickness. Specifically: (a) By changing the type of metal salt, complexing agent, and microsphere template used in step (1), integrated carbon honeycomb structure materials with different chemical compositions can be prepared; (b) By changing the mold shape, precursor dosage, applied pressure, and holding time in step (3), the geometry, area, and thickness of the integrated carbon honeycomb structure material can be easily adjusted. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 These are optical photographs of the integrated carbon honeycomb structure materials prepared in Examples 1–8, wherein: (a) is a planar photograph and (b) is a side photograph.

[0021] Figure 2These are scanning electron microscope (SEM) images of the planar (high magnification and low magnification) and cross-sectional positions of the integrated carbon honeycomb structure materials obtained in Examples 1–8. Specifically, (a) is the SEM image of sample 1 (prepared in Example 1 by calcining at 360°C using zinc nitrate-citric acid as a precursor); (b) is the SEM image of sample 2 (prepared in Example 2 by calcining at 1100°C using zinc nitrate-citric acid as a precursor); (c) is the SEM image of sample 3 (prepared in Example 3 by calcining at 380°C using nickel nitrate-citric acid as a precursor); and (d) is the SEM image of sample 4 (prepared in Example 4 by calcining at 1050°C using nickel nitrate-citric acid as a precursor. (e) is a SEM image of sample 5 prepared by calcining aluminum nitrate-citric acid as a precursor at 370°C in Example 5; (f) is a SEM image of sample 6 prepared by calcining aluminum nitrate-citric acid as a precursor at 1050°C in Example 6; (g) is a SEM image of sample 7 prepared by calcining ferric nitrate-citric acid as a precursor at 370°C in Example 7; and (h) is a SEM image of sample 8 prepared by calcining ferric nitrate-citric acid as a precursor at 1000°C in Example 8.

[0022] Figure 3 The images show the X-ray diffraction (XRD) patterns of the integrated carbon honeycomb structure materials prepared in Examples 1–8, where: (a) are the XRD patterns of samples 1 and 2 prepared from zinc nitrate; (b) are the XRD patterns of samples 3 and 4 prepared from nickel nitrate; (c) are the XRD patterns of samples 5 and 6 prepared from aluminum nitrate; and (d) are the XRD patterns of samples 7 and 8 prepared from ferric nitrate.

[0023] Figure 4 The images show the Raman spectra of the integrated carbon honeycomb structure materials prepared in Examples 1–8, where: (a) are the Raman spectra of samples 1 and 2 prepared using zinc nitrate as raw material; (b) are the Raman spectra of samples 3 and 4 prepared using nickel nitrate as raw material; (c) are the Raman spectra of samples 5 and 6 prepared using aluminum nitrate as raw material; and (d) are the Raman spectra of samples 7 and 8 prepared using ferric nitrate as raw material. Detailed Implementation

[0024] To further illustrate the present invention, the following detailed description, in conjunction with the accompanying drawings and embodiments, describes the integrated carbon honeycomb structure material provided by the present invention, but these descriptions should not be construed as limiting the scope of protection of the present invention. Any product identical or similar to the present invention, derived from the teachings of the present invention or by combining features of the present invention with other prior art, should fall within the scope of protection of the present invention.

[0025] The specific operating and testing methods used in this invention are all conventional methods in the field. Unless otherwise specified, conventional experimental operations or conditions described in the literature in this field can be followed. The reagents involved in this invention are all existing commercially available products.

[0026] All embodiments of this patent use a commercial infrared tablet press for precursor tableting. The shape and size of the mold and other physical parameters can be freely adjusted according to requirements. This patent uses a cylindrical mold with a diameter of 15.4 mm to prepare samples for the following embodiments.

[0027] Example 1

[0028] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (a) It can be seen that the obtained integrated carbon honeycomb structure material (sample 1) is in the shape of a disc, with a geometric diameter of approximately 13.6 mm and a uniform thickness of approximately 520 μm; Figure 3 (a) and Figure 4 (a) It is known that this material is composed of zinc oxide with low crystallinity and graphene-like carbon with low graphitization. Its preparation method includes the following steps:

[0029] (1) Zinc nitrate and citric acid were prepared into a solution as a precursor impregnation solution; the concentration of citric acid in the precursor solution was 1 mol / L and the concentration of Zn(NO3)2·6H2O was 2 mol / L.

[0030] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0031] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0032] (4) Place the disc-shaped precursor from step (3) in a tube furnace for calcination: in a hydrogen-argon mixed atmosphere of 200 sccm, heat to 360°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0033] Example 2

[0034] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (b) It can be seen that the obtained integrated carbon honeycomb structure material (sample 2) is in the shape of a disc, with a geometric diameter of approximately 9.5 mm and a uniform thickness of approximately 300 μm, which is significantly lower than that of sample 1;Figure 3 (a) and Figure 4 (a) It is known that this material does not contain zinc oxide and is composed of pure, defect-rich graphene-like carbon. Its preparation method includes the following steps:

[0035] (1) Zinc nitrate and citric acid were prepared into a solution as a precursor impregnation solution; the concentration of citric acid in the precursor solution was 1 mol / L and the concentration of Zn(NO3)2·6H2O was 2 mol / L.

[0036] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0037] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0038] (4) Place the disc-shaped precursor from step (3) in a tube furnace for calcination: in a hydrogen-argon mixed atmosphere of 200 sccm, heat to 1100℃ at a heating rate of 4℃ / min, hold for 30 min and then cool to room temperature to obtain the product.

[0039] Example 3

[0040] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (c) It can be seen that the obtained integrated carbon honeycomb structure material (sample 3) is in the shape of a disc, with a geometric diameter of approximately 11.2 mm and a uniform thickness of approximately 440 μm; Figure 3 (b) and Figure 4 (b) It is known that this material is composed of low-crystallinity metallic nickel and defect-rich graphene-like carbon. Its preparation method includes the following steps:

[0041] (1) Prepare a solution of nickel nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Ni(NO3)2·6H2O is 2 mol / L.

[0042] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0043] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0044] (4) Place the circular precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 380°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0045] Example 4

[0046] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (d) It can be seen that the obtained integrated carbon honeycomb structure material (sample 4) is in the shape of a disc, with a geometric diameter of approximately 10.9 mm and a uniform thickness of approximately 435 μm, slightly lower than that of sample 3; Figure 3 (b) and Figure 4 (b) It is known that this material is composed of highly crystalline metallic nickel and graphene-like carbon. Its preparation method includes the following steps:

[0047] (1) Prepare a solution of nickel nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Ni(NO3)2·6H2O is 2 mol / L.

[0048] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0049] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0050] (4) Place the circular precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 1050°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0051] Example 5

[0052] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (e) It can be seen that the obtained integrated carbon honeycomb structure material (sample 5) is in the shape of a disc, with a geometric diameter of approximately 13.5 mm and a uniform thickness of approximately 515 μm; Figure 3 (c) and Figure 4 (c) It is evident that this material is composed of low-crystallinity alumina and defect-rich graphene-like carbon. Its preparation method includes the following steps:

[0053] (1) Prepare a solution of aluminum nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Al(NO3)2·9H2O is 2 mol / L.

[0054] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0055] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0056] (4) Place the disc-shaped precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 370°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0057] Example 6

[0058] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (f) It can be seen that the obtained integrated carbon honeycomb structure material (sample 6) is in the shape of a disc, with a geometric diameter of approximately 10.5 mm and a uniform thickness of approximately 430 μm, which is significantly lower than that of sample 5; Figure 3 (c) and Figure 4 (c) It is evident that this material is composed of low-crystallinity alumina and defect-rich graphene-like carbon. Its preparation method includes the following steps:

[0059] (1) Prepare a solution of aluminum nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Al(NO3)2·9H2O is 2 mol / L.

[0060] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0061] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0062] (4) Place the circular precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 1050°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0063] Example 7

[0064] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (g) It can be seen that the obtained integrated carbon honeycomb structure material (sample 7) is in the shape of a disc, with a geometric diameter of approximately 9.9 mm and a uniform thickness of approximately 425 μm; Figure 3 (d) and Figure 4 (d) It can be seen that this material is composed of low-crystallinity iron oxide and graphene-like carbon. Its preparation method includes the following steps:

[0065] (1) Prepare a solution of ferric nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Fe(NO3)2·9H2O is 2 mol / L.

[0066] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0067] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0068] (4) Place the disc-shaped precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 350°C at a heating rate of 4°C / min, hold for 30 min and then cool to room temperature to obtain the product.

[0069] Example 8

[0070] This embodiment provides an integrated, one-piece carbon honeycomb structure material. (The material is made from...) Figure 1 and Figure 2 (h) shows that the obtained integrated carbon honeycomb structure material (sample 8) is in the shape of a disc, with a geometric diameter of approximately 7.7 mm and a uniform thickness of approximately 330 μm, which is significantly lower than that of sample 7; Figure 3 (d) and Figure 4 Figure 1 Figure 2 Figure 3 Figure 4 (d) It can be seen that this material is composed of iron carbide and graphene-like carbon rich in defects. Its preparation method includes the following steps:

[0071] (1) Prepare a solution of ferric nitrate and citric acid as a precursor impregnation solution; the concentration of citric acid in the precursor solution is 1 mol / L and the concentration of Fe(NO3)2·9H2O is 2 mol / L.

[0072] (2) The irregular block or small particle-shaped PMMA microsphere template was immersed in the above precursor solution for 12 hours, filtered and dried to obtain the initial precursor.

[0073] (3) Weigh 120mg of the precursor from step (2), place it in a cylindrical mold with a diameter of 15.4mm for tableting, and hold it under a pressure of 6MPa for 30s to obtain a circular tablet precursor.

[0074] (4) Place the disc-shaped precursor from step (3) in a tube furnace for calcination: in an argon atmosphere of 200 sccm, heat to 1000℃ at a heating rate of 4℃ / min, hold for 30 min and then cool to room temperature to obtain the product.

Claims

1. A method for preparing an integrated carbon honeycomb structure material, comprising the following steps: (1) Prepare a solution by mixing the complexing agent and the metal salt in a certain proportion as a precursor impregnation solution; (2) The organic colloidal microsphere template with irregular block or small particle shape is fully impregnated in the above precursor impregnation solution, filtered and dried to obtain the primary precursor; (3) Weigh the primary precursor from step (2), place it in a mold for tableting, and hold it under a certain pressure for a period of time to obtain a macroscopic block-shaped precursor with the shape of the mold. (4) The precursor pressed into a block shape in step (3) is placed in a tube furnace and calcined at a set temperature under a specific atmosphere for a period of time. After calcination, it is cooled to room temperature to obtain an integrated carbon honeycomb structure material with a macroscopic mold shape. The pore walls of the honeycomb structure are graphene carbon matrix inlaid with metal and / or metal compounds. The complexing agent is selected from citric acid, and the metal salt is selected from zinc nitrate, nickel nitrate, aluminum nitrate, and ferric nitrate; the template for the organic colloidal microspheres is PMMA. The concentration of citric acid complexing agent in the precursor impregnation solution prepared in step (1) is 0.5–2 mol / L, and the concentration of metal salt is 1–3 mol / L; The target calcination temperature in step (4) is 350–1200 °C; the reaction atmosphere is nitrogen, argon or a mixture of hydrogen and argon.

2. The method according to claim 1, characterized in that, The concentration of citric acid complexing agent in the precursor impregnation solution prepared in step (1) is 1 mol / L; The concentration of the metal salt is 2 mol / L.

3. The method according to claim 1, characterized in that, In step (2), the immersion conditions are immersion at room temperature for 3–16 h.

4. The method according to claim 1, characterized in that, In step (3), the applied pressure is 4–10 MPa; the pressure is maintained for 10–60 s.

5. The method according to claim 4, characterized in that, In step (3), the applied pressure is 6 MPa; the pressure is maintained for 30 s.

6. The method according to claim 1, characterized in that, Step (4) The heating rate is 1–30℃ / min; the gas flow rate is 1–500 sccm; and the holding time is 30min–2h.

7. The method according to claim 6, characterized in that, Step (4) The heating rate is 4 ℃ / min; the gas flow rate is 200 sccm.

8. An integrated carbon honeycomb structure material prepared according to any one of claims 1-7.

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