Search

CN-121990838-A - Three-dimensional continuous graphite network structure material and preparation method and device thereof

CN121990838ACN 121990838 ACN121990838 ACN 121990838ACN-121990838-A

Abstract

The invention discloses a three-dimensional continuous graphite network structure material, a preparation method and a device thereof. The preparation method comprises the steps of S1, introducing carbon source gas into a reactor filled with a carbon fiber framework, carrying out pyrolysis reaction on the carbon source gas at 1100-1500 ℃, growing pyrolytic carbon generated by the reaction on the carbon fiber framework to obtain a pyrolytic carbon coated carbon fiber structure, S2, carrying out graphitization treatment on the carbon fiber structure in an inert atmosphere to form a three-dimensional continuous graphite network structure material, wherein the graphitization treatment temperature is more than or equal to 2500 ℃. Unlike traditional CVI densification process, the invention uses carbon fiber skeleton with low volume fraction as growth template rather than reinforcing phase, and through precise control of growth space and conditions, continuous graphite network material with isotropy, high heat conductivity, high electric conductivity and adjustable density is obtained, and is suitable for use in heat management, electrode and other fields.

Inventors

  • WU WENXIN
  • YU QINGKAI
  • SHAO JIN
  • HUANG XUESONG

Assignees

  • 上海氢田新材料科技有限公司

Dates

Publication Date
20260508
Application Date
20260212

Claims (10)

  1. 1. The preparation method of the three-dimensional continuous graphite network structure material is characterized by comprising the following steps of: s1, introducing carbon source gas into a reactor filled with a carbon fiber framework, wherein the carbon source gas undergoes pyrolysis reaction, pyrolytic carbon generated by the reaction grows on the carbon fiber framework to obtain a pyrolytic carbon-coated carbon fiber structure, and the temperature of the pyrolysis reaction is 1100-1500 ℃; The carbon fiber skeleton is a non-woven carbon fiber skeleton, the average distance between carbon fibers in the carbon fiber skeleton is 20-500 mu m, the initial volume fraction of the carbon fiber skeleton is less than 10%, and the initial volume fraction is the ratio of the volume of the carbon fibers to the stacking volume of the carbon fibers; and S2, carrying out graphitization treatment on the carbon fiber structure in an inert atmosphere to form the three-dimensional continuous graphite network structure material, wherein the graphitization treatment temperature is more than or equal to 2500 ℃.
  2. 2. The method of claim 1, wherein step S1 satisfies at least one of the following conditions: i. The average distance between carbon fibers in the carbon fiber skeleton is 50-300 mu m; ii. The preparation method of the carbon fiber skeleton comprises the steps of randomly stacking carbon fibers or stacking carbon fibers in a controlled orientation manner; iii, the raw materials of the carbon fiber skeleton comprise chopped carbon fibers or continuous carbon fibers; iv the initial volume fraction of the carbon fiber skeleton is 0.1% -5%.
  3. 3. The method according to claim 2, wherein in step S1, the method for producing the carbon fiber skeleton comprises opening the carbon fibers by using a mechanical needle roller and feeding a gas into the carbon fibers to form a three-dimensional network structure.
  4. 4. The method of claim 1, wherein in step S1, the carbon source gas is selected from one or more of methane, ethane, ethylene, propylene, and natural gas.
  5. 5. The method of claim 1, wherein step S1 satisfies at least one of the following conditions: i. the growth time is 1-10 h; ii. The growth rate is 5-50 mu m/h; and iii, the pressure condition of the pyrolysis reaction is normal pressure.
  6. 6. The method of claim 1, wherein step S2 satisfies at least one of the following conditions: i. The graphitization treatment temperature is 2500-3000 ℃; ii. The graphitization treatment time is 1-10 h.
  7. 7. A three-dimensional continuous graphite network structure material, characterized in that it is produced by the production method according to any one of claims 1 to 6.
  8. 8. The three-dimensional, continuous graphite network structure material of claim 7, wherein the density of the three-dimensional, continuous graphite network structure material is from 0.1 to 1.7 g/cm 3 ; When the density of the three-dimensional continuous graphite network structure material is more than 1 g/cm 3 , the heat conductivity coefficient of at least one direction in the three-dimensional continuous graphite network structure material is more than 200W/(m.K), and the resistivity is less than 8 multiplied by 10 -4 ohm.cm.
  9. 9. A thermal management device comprising a three-dimensional continuous graphite network structure material according to claim 7 or 8.
  10. 10. An electrode device comprising the three-dimensional continuous graphite network material according to claim 7 or 8.

Description

Three-dimensional continuous graphite network structure material and preparation method and device thereof Technical Field The invention belongs to the technical field of carbon material preparation, and particularly relates to a three-dimensional continuous graphite network structure material, a preparation method and a device thereof. Background With the progress of technology, the integration level of electronic devices and industrial devices is increased, and the power density and the heat productivity of the electronic devices and the industrial devices are also increased. Especially for high-precision instruments, the internal heat accumulation can directly reduce the reliability of electronic devices, thereby affecting the measurement accuracy and the operation stability of the equipment. Therefore, the development of high-performance heat conducting materials is a key to solving how to efficiently conduct out the accumulated heat. Graphene, which is a potential heat conducting material, has a heat conductivity as high as 5300W/(m.K) and is a material with better heat conductivity known at present. The prior art discloses a method for preparing a three-dimensional graphene network by adopting a metal template method, and the product obtained by the method is graphene aerogel/foam with low density and thin wall, and the product has low mechanical strength and poor absolute heat conduction performance although the product has high specific surface area and conductivity, and cannot be used as a load-carrying structure or an efficient heat radiator. The prior art discloses the preparation of C/C composite materials by conventional CVI (chemical vapor infiltration) process, which uses a high volume fraction (> 20%) of the fibrous preform as the reinforcing phase, and aims at complete densification (pore filling) and the product is a two-phase composite material of fibers and matrix carbon, the properties of which are limited by interfaces and grain boundaries, and it is difficult to obtain isotropic single-crystal/quasi-single-crystal continuum, thus affecting its thermal conductivity. Accordingly, there is a need to provide a graphite material that is isotropic and has high thermal and electrical conductivity. Disclosure of Invention In order to solve the problems, the invention provides a three-dimensional continuous graphite network structure material, a preparation method and a device thereof. The three-dimensional continuous graphite network structure material prepared by the invention has isotropy, namely, the performances in different directions (such as three vector directions of space coordinate axes x, y and z) are basically not different, and meanwhile, the three-dimensional continuous graphite network structure material has the performances of high heat conduction and high electric conduction, is adjustable in density, is suitable for the fields of heat management, electrodes and the like, and can be manufactured into related devices. The prior preparation method of the graphite material generally adopts braided carbon fibers as a reinforcing phase to be compounded with matrix carbon to form the graphite material, wherein the braided carbon fibers are obtained by two-dimensional or three-dimensional braiding of bundled carbon fibers as warps and wefts, which leads to insufficient deposition space in bundles and seriously reduces the surface utilization rate of the braided carbon fibers, the heat conductivity and the electric conductivity of the product are influenced by a network braiding method, the isotropy effect cannot be achieved, and in addition, the volume ratio and the weight ratio of the braided carbon fibers are higher for a network structure of the braided carbon fibers. The invention solves the problems by the following technical proposal: the invention provides a preparation method of a three-dimensional continuous graphite network structure material, which comprises the following steps: s1, introducing carbon source gas into a reactor filled with a carbon fiber framework, wherein the carbon source gas undergoes pyrolysis reaction, pyrolytic carbon generated by the reaction grows on the carbon fiber framework to obtain a pyrolytic carbon-coated carbon fiber structure, and the temperature of the pyrolysis reaction is 1100-1500 ℃; The carbon fiber skeleton is a non-woven carbon fiber skeleton, the average distance between carbon fibers in the carbon fiber skeleton is 20-500 mu m, the initial volume fraction of the carbon fiber skeleton is less than 10%, and the initial volume fraction is the ratio of the volume of the carbon fibers to the stacking volume of the carbon fibers; and S2, carrying out graphitization treatment on the carbon fiber structure in an inert atmosphere to form the three-dimensional continuous graphite network structure material, wherein the graphitization treatment temperature is more than or equal to 2500 ℃. Unlike the densification process of the conventional