Preparation Method of Graphitized Mesoporous Carbon Support

Abstract

The embodiments of the present application relate to the technical field of fuel cells, and provide a preparation method of a graphitized mesoporous carbon support, which is beneficial to the carbon support having the characteristics of high graphitization degree and high mesoporous capacity. The preparation method includes: providing an initial carbon support; performing a pre-oxidation treatment by dispersing the initial carbon support in an oxidizing solution and carrying out a reflux treatment to obtain a pre-oxidized carbon support; performing a functionalization treatment on the pre-oxidized carbon support by dispersing the pre-oxidized carbon support in a water-alcohol solution containing a weakly basic solvent and then adjusting the pH value of the reaction solution to an alkaline condition for reaction to obtain a functionalized carbon support; performing a hydrolysis reaction on the functionalized carbon support and a silicon source to obtain a target carbon support, wherein amorphous silica is present in the pores of the target carbon support; performing a graphitization treatment on the target carbon support to obtain an initial mesoporous carbon material; and performing an alkali washing treatment on the initial mesoporous carbon material to obtain a target mesoporous carbon material.

Description

Technical Field

[0001] This application relates to the technical field of fuel cells, and particularly to a method for preparing a graphitized mesoporous carbon support. Background Art

[0002] Mesoporous materials are a kind of porous solid materials, which have the characteristics of high specific surface area, large pore size, etc. Their pore channels are arranged regularly and orderly, and the pore size distribution is uniform (generally 2nm - 50nm). Therefore, they are often used as catalysts or catalyst supports and play an important role in fields such as adsorption and desorption, catalysis, etc. Mesoporous carbon materials not only have the advantages of ordinary mesoporous materials, but also have electronic conductivity. Therefore, they can also be widely used as electrode materials or catalyst supports in electrochemical energy storage and conversion systems such as electrochemical supercapacitors, lithium-ion batteries, fuel cells, etc.

[0003] The catalysts of proton exchange membrane fuel cells (PEMFC) mainly include platinum-carbon catalysts and platinum-alloy catalysts, etc. Platinum-carbon catalysts and platinum-alloy catalysts usually select mesoporous carbon materials as the carriers of catalytic metal particles. However, during the operation of fuel cells, the mesoporous carbon support is prone to oxidative corrosion, resulting in a decline in the catalytic performance of the catalyst. In order to improve the stability of the carbon support, a calcination method can be used. For example, carbon black is placed in a tubular furnace and calcined at a temperature of 1400°C - 2000°C in an inert atmosphere. However, the simple high-temperature treatment method not only improves the graphitization degree of the carbon support but also causes the loss of pores and specific surface area of the carbon support, resulting in a low catalytic activity of the prepared catalyst, and the improvement space for the durability of the carbon support is also limited. Summary of the Invention

[0004] The embodiments of this application provide a method for preparing a graphitized mesoporous carbon support, which is beneficial for the carbon support to have the characteristics of high graphitization degree and high mesopore capacity.

[0005] According to some embodiments of this application, on the one hand, the embodiments of this application provide a method for preparing a graphitized mesoporous carbon support, including: providing an initial carbon support; performing a pre-oxidation treatment, dispersing the initial carbon support in an oxidizing solution and performing a reflux treatment to obtain a pre-oxidized carbon support; performing a functionalization treatment on the pre-oxidized carbon support, dispersing the pre-oxidized carbon support in a water-alcohol solution containing a weakly basic solvent, and then adjusting the pH value of the reaction solution to an alkaline condition for reaction to obtain a functionalized carbon support; performing a hydrolysis reaction on the functionalized carbon support and a silicon source to obtain a target carbon support, and amorphous silica is present in the pores of the target carbon support; performing a graphitization treatment on the target carbon support to obtain an initial mesoporous carbon material; performing an alkali washing treatment on the initial mesoporous carbon material to obtain a target mesoporous carbon material.

[0006] In some embodiments, in the step of pre-oxidation treatment, the oxidant in the oxidizing solution is selected from at least one of concentrated nitric acid, concentrated hydrochloric acid, hydrogen peroxide, potassium permanganate, sodium hypochlorite or bromine water; the concentration of the oxidant in the oxidizing solution is 2 mol / L to 4 mol / L.

[0007] In some embodiments, in the step of pre-oxidation treatment, the temperature for reflux treatment is 80°C to 120°C, and the time is 4 h to 8 h.

[0008] In some embodiments, in the step of functionalization treatment, the weak basic solvent is selected from at least one of lysine or ammonia water; the water-alcohol solution includes ethanol and water with a volume ratio of 1:(0.5 to 1.5); the concentration of the weak basic solvent is 0.8 mol / L to 1.2 mol / L.

[0009] In some embodiments, the step of functionalization treatment includes: dispersing the pre-oxidized carbon support in a water-alcohol solution containing a weak basic solvent at a temperature of 5°C to 15°C, and if the pH value of the reaction system does not change within 3 min to 6 min, then adjusting the pH value of the reaction solution to 12 to 14 and continuing the reaction for 6 h to 10 h.

[0010] In some embodiments, the reagent used to adjust the pH value of the reaction system is a sodium hydroxide solution with a concentration of 0.05 mol / L to 1.5 mol / L.

[0011] In some embodiments, in the step of hydrolysis reaction, the silicon source is selected from at least one of methyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), polyethoxydisiloxane (PEDS), methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES) or sodium silicate (Na2SiO3).

[0012] In some embodiments, the step of hydrolysis reaction includes: dispersing the functionalized carbon support in a mixed solution of water and ethanol with a molar ratio of 1:(2.5 to 3.5) and dropwise adding the silicon source, wherein the molar ratio of the silicon source to water is (0.5 to 1):1; the hydrolysis reaction time is 20 h to 30 h, and the temperature is 40°C to 80°C.

[0013] In some embodiments, the step of graphitization treatment includes: placing the target carbon support in a graphitization furnace, first heating it to 1000°C to 1300°C at a rate of 3°C / min to 5°C / min; then heating it to 1400°C to 1600°C at a rate of 1°C / min to 2°C / min and holding for 0.5 h to 2 h.

[0014] In some embodiments, the steps of the alkali washing treatment include: dispersing the initial mesoporous carbon material in a sodium hydroxide solution with a concentration of 0.1 mol / L to 0.5 mol / L at 20°C to 25°C for washing for 10 h to 14 h, and obtaining the target mesoporous carbon material through filtration and drying.

[0015] The technical solutions provided by the embodiments of the present application have at least the following advantages:

[0016] The preparation method of the graphitized mesoporous carbon support provided by the embodiments of the present application sequentially performs pre-oxidation treatment, functionalization treatment, hydrolysis reaction, graphitization treatment, and alkali washing treatment on the initial carbon support to obtain the target mesoporous carbon material. Through the pre-oxidation treatment, the surface of the initial carbon support is treated, and the obtained pre-oxidized carbon support has good dispersion performance; then the pre-oxidized carbon support is subjected to functionalization treatment, so that functional groups on the surface and pore walls of the pre-oxidized carbon support graft or adsorb basic groups to obtain a functionalized carbon support; the functionalized carbon support is subjected to a hydrolysis reaction with a silicon source, so that the basic groups react with the hydrolyzed silicon source to generate amorphous silica, and the amorphous silica remains on the surface and in the pores of the target carbon support; in the subsequent graphitization treatment step, the silica plays a confinement role on the pores of the target carbon support, avoiding the problem of collapse or shrinkage of the pores of the target carbon support during the graphitization treatment process; finally, the initial mesoporous carbon material is subjected to alkali washing treatment to remove the silica on the surface and in the pores, obtaining a target carbon support with both high graphitization degree and high mesopore capacity, improving the durability and catalytic activity of platinum-carbon catalysts, platinum-alloy catalysts, etc. using it as a support. Description of the Drawings

[0017] One or more embodiments are exemplarily illustrated by the pictures in the corresponding drawings. These exemplary illustrations do not constitute a limitation on the embodiments. Unless otherwise stated, the figures in the drawings do not constitute a proportional limitation; in order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the following-described drawings are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0018] Figure 1 It is a flowchart corresponding to the preparation method of the graphitized mesoporous carbon support provided by the embodiments of the present application. Detailed Embodiments

[0019] As can be seen from the background art, currently, when improving the graphitization degree of the carbon support by calcination, it is easy to cause the loss of the pores and specific surface area of the carbon support, resulting in low catalytic activity of the catalyst and unable to meet the actual requirements of fuel cells.

[0020] In the related art, the stability of the carbon support is improved by assisted graphitization. For example, the carbon support is coated with a metal chloride salt so that the carbon support retains its pore structure during the graphitization process of calcination. However, the melting point of the metal chloride salt is usually relatively low, and the graphitization temperature during the calcination process is high, which may cause the molten decomposition of the metal chloride salt. In addition, the metal chloride salt may only be adsorbed in the pores of the carbon support in a small amount and cannot play a good confinement role, resulting in a poor retention degree of the pore structure of the carbon support.

[0021] The embodiment of the present application provides a method for preparing a graphitized mesoporous carbon support. By virtue of the good water solubility of the silica precursor component, the silica precursor component penetrates into the pores of the carbon support, and then the silica obtained after its hydrolysis is retained in the pores of the carbon support as a confinement component. Based on the high hardness and high stability of silica, the confinement effect can be realized to reduce the shrinkage or collapse problem of the carbon support during the graphitization treatment, and thus the finally obtained carbon support has the characteristics of high graphitization degree and high mesopore capacity.

[0022] Referring to "embodiment" herein means that the specific features, structures or characteristics described in connection with the embodiment may be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0023] The following will elaborate on each embodiment of the present application with reference to the accompanying drawings. However, those of ordinary skill in the art can understand that in each embodiment of the present application, many technical details are proposed for the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical solutions claimed in the present application can be implemented.

[0024] Figure 1 It is a flowchart corresponding to the method for preparing a graphitized mesoporous carbon support provided by the embodiment of the present application.

[0025] Refer to Figure 1 , the method for preparing a graphitized mesoporous carbon support includes:

[0026] Step 101: Provide an initial carbon support.

[0027] The initial carbon support may be at least one of carbon black EC-600JD, carbon black EC-300JD, carbon black VXC-72, carbon black BP2000 or carbon nanotubes.

[0028] Step 102: Perform pre-oxidation treatment. Disperse the initial carbon support in an oxidizing solution and conduct reflux treatment to obtain a pre-oxidized carbon support.

[0029] The initial carbon support usually has a large specific surface area and high surface free energy, making it prone to agglomeration, which in turn leads to poor dispersibility of the initial carbon support. Pre-oxidation treatment is beneficial for changing the non-polar surface of the initial support into a polar surface, increasing the oxygen-containing polar groups on the surface of the initial carbon support, such as hydroxyl, carboxyl, carbonyl, quinone, and lactone groups, etc. As a result, the adsorption force between the initial carbon support particles is reduced, and the binding force between the initial carbon support and the matrix is increased, thus improving the dispersibility of the initial carbon support in the solvent.

[0030] In the step of pre-oxidation treatment, the oxidant in the oxidizing solution can be selected from at least one of concentrated nitric acid, concentrated hydrochloric acid, hydrogen peroxide, potassium permanganate, sodium hypochlorite, or bromine water.

[0031] The concentration of the oxidant in the oxidizing solution can be 2 mol / L to 4 mol / L. For example, specifically, it can be 2 mol / L, 2.3 mol / L, 2.6 mol / L, 2.8 mol / L, 3 mol / L, 3.2 mol / L, 3.4 mol / L, 3.7 mol / L, or 4 mol / L, etc.

[0032] In the step of pre-oxidation treatment, the temperature for reflux treatment can be 80°C to 120°C. For example, specifically, it can be 80°C, 90°C, 100°C, 110°C, or 120°C, etc.; the time for reflux treatment can be 4 h to 8 h. For example, specifically, it can be 4 h, 4.5 h, 5 h, 5.6 h, 6 h, 6.4 h, 7 h, 7.5 h, or 8 h, etc.

[0033] After pre-oxidation treatment, it can also include filtration, washing, and drying to improve the purity of the pre-oxidized carbon support, while removing impurities and oxidants in the pre-oxidized carbon support to avoid contamination of subsequent steps.

[0034] Step 103: Perform functionalization treatment on the pre-oxidized carbon support. After dispersing the pre-oxidized carbon support in an aqueous alcohol solution containing a weakly basic solvent, adjust the pH value of the reaction solution to an alkaline condition for reaction to obtain a functionalized carbon support.

[0035] The pre-oxidized carbon support obtained after pre-oxidation treatment has good dispersibility in the aqueous alcohol solution, which enables the weakly basic groups in the weakly basic solvent to penetrate into the surface and pores of the pre-oxidized carbon support, and adsorb or graft weakly basic functional groups on the surface and pore walls of the pre-oxidized carbon support.

[0036] Specifically, the steps of the functionalization treatment may include: under the condition that the temperature is 5°C to 15°C (for example, specifically 5°C, 8°C, 10°C, 13°C or 15°C, etc.), after dispersing the pre-carbonized carrier in an aqueous alcohol solution containing a weakly basic solvent, within 3 min to 6 min (for example, specifically 3 min, 4 min, 5 min or 6 min, etc.), if the pH value of the reaction system does not change, then adjust the pH value of the reaction solution to 12 to 14 (for example, specifically 12, 13 or 14), and continue the reaction for 6 h to 10 h (for example, specifically 6 h, 7 h, 8 h, 9 h or 10 h, etc.). After dispersing the pre-carbonized carrier in the aqueous alcohol solution, adjusting the pH value of the reaction solution to alkaline after the pH value of the reaction system remains unchanged within a certain time is beneficial to maintaining the stability of the reaction, and further improving the stability of the grafting or adsorption of the weakly basic groups.

[0037] The reagent used to adjust the pH value of the reaction system can be a sodium hydroxide solution with a concentration of 0.05 mol / L to 1.5 mol / L. Specifically, the concentration of the sodium hydroxide solution can be 0.05 mol / L, 0.5 mol / L, 1 mol / L, 1.2 mol / L or 1.5 mol / L, etc.

[0038] In the steps of the functionalization treatment, the weakly basic solvent can be selected from at least one of lysine or ammonia water; the aqueous alcohol solution can include ethanol and water with a volume ratio of 1:(0.5 to 1.5). The volume ratio of ethanol to water can be specifically 1:0.5, 1:1 or 1:1.5, etc.; the concentration of the weakly basic solvent can be 0.8 mol / L to 1.2 mol / L, for example, specifically 0.8 mol / L, 0.9 mol / L, 1 mol / L, 1.1 mol / L or 1.2 mol / L, etc.

[0039] After the functionalization treatment, it may also include filtration, washing and drying to improve the purity of the functionalized carbon carrier, and at the same time remove impurities and basic solvents in the functionalized carbon carrier to avoid contamination of subsequent steps.

[0040] Step 104: Perform a hydrolysis reaction on the functionalized carbon carrier and a silicon source to obtain a target carbon carrier, and amorphous silica is present in the pores of the target carbon carrier.

[0041] The hydrolysis reaction occurs on the surface and in the pores of the functionalized carbon carrier, and amorphous silica is formed in-situ. The amorphous silica retained in the pores of the target carbon carrier has high hardness and thermal stability to support the pores in subsequent steps.

[0042] In the hydrolysis reaction step, the silicon source can be selected from at least one of methyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), polyethoxydisiloxane (PEDS), methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES), or sodium silicate (Na2SiO3).

[0043] Taking TMOS as the silicon source as an example, the hydrolysis reaction step includes: dispersing the functionalized carbon support in a mixed solution of water and ethanol with a molar ratio of 1:(2.5 - 3.5) and dropwise adding TMOS. For example, the molar ratio of water to ethanol can specifically be 1:2.5, 1:2.8, 1:3, 1:3.3, or 1:3.5, etc.; among them, the molar ratio of the silicon source to water is (0.5 - 1):1. For example, the molar ratio of the silicon source to water can specifically be 0.5:1, 0.6:1, 0.7:1, 0.8:1, 0.9:1, or 1:1, etc.; the hydrolysis reaction time can be 20h - 30h. For example, it can specifically be 20h, 22h, 24h, 26h, 28h, or 30h, etc.; the hydrolysis reaction temperature can be 40°C - 80°C. For example, it can specifically be 40°C, 45°C, 50°C, 55°C, 60°C, 65°C, 70°C, 75°C, or 80°C, etc.

[0044] During the hydrolysis reaction process, a vacuum adsorption treatment can also be included. The vacuum adsorption treatment is: connecting a vacuum pump to the container containing the above hydrolysis reaction raw materials and adjusting the pressure to the required value. Considering the rationality and orderliness of the overall hydrolysis adsorption process, the adsorption pressure generally does not exceed -0.1 MPa, and the adsorption time is kept the same as the hydrolysis reaction time to achieve a uniform and orderly adsorption hydrolysis effect.

[0045] After the hydrolysis reaction, filtration, washing, and drying can also be included to improve the purity of the target carbon support, and at the same time remove impurities and the silicon source in the target carbon support to avoid contamination of subsequent steps.

[0046] Step 105: Graphitize the target carbon support to obtain the initial mesoporous carbon material.

[0047] The higher the graphitization degree, the smaller the graphite layer spacing, the better the conductivity, and the more complete the crystal structure, which is very important for improving the conductivity and stability of the catalyst.

[0048] The steps of graphitization treatment may include: placing the target carbon support in a graphitization furnace, first heating it at a rate of 3 °C / min to 5 °C / min (for example, specifically 3 °C / min, 4 °C / min or 5 °C / min) to 1000 °C to 1300 °C (for example, specifically 1000 °C, 1100 °C, 1150 °C, 1200 °C, 1250 °C or 1300 °C); then heating it at a rate of 1 °C / min to 2 °C / min (for example, specifically 1 °C / min or 2 °C / min) to 1400 °C to 1600 °C (for example, specifically 1400 °C, 1500 °C or 1600 °C), and then holding the temperature for 0.5 h to 2 h (for example, specifically 0.5 h, 0.8 h, 1 h, 1.3 h, 1.6 h, 1.8 h or 2 h).

[0049] Step 106: Perform alkali washing treatment on the initial mesoporous carbon material to obtain the target mesoporous carbon material.

[0050] The alkali washing treatment can remove the silica component in the initial mesoporous carbon material to obtain the target mesoporous carbon material with a higher graphitization degree and a complete pore structure retained.

[0051] In some embodiments, the steps of the alkali washing treatment include: dispersing the initial mesoporous carbon material in a sodium hydroxide solution with a concentration of 0.1 mol / L to 0.5 mol / L (for example, specifically 0.1 mol / L, 0.2 mol / L, 0.3 mol / L, 0.4 mol / L or 0.5 mol / L) at 20 °C to 25 °C (for example, specifically 20 °C, 21 °C, 22 °C, 23 °C, 24 °C or 24 °C) and washing for 10 h to 14 h (for example, specifically 10 h, 11 h, 12 h, 13 h or 14 h), and obtaining the target mesoporous carbon material through filtration and drying.

[0052] The preparation method of the graphitized mesoporous carbon support provided by the embodiments of the present application sequentially performs pre-oxidation treatment, functionalization treatment, hydrolysis reaction, graphitization treatment, and alkali washing treatment on the initial carbon support to obtain the target mesoporous carbon material. Through the pre-oxidation treatment, the surface of the initial carbon support is treated, and the obtained pre-oxidized carbon support has good dispersion performance; then the pre-oxidized carbon support is subjected to functionalization treatment, so that functional groups on the surface and pore walls of the pre-oxidized carbon support graft or adsorb basic groups to obtain a functionalized carbon support; the functionalized carbon support is subjected to a hydrolysis reaction with a silicon source, so that the basic groups react with the hydrolyzed silicon source to generate amorphous silica, and the amorphous silica remains on the surface and in the pores of the target carbon support; in the subsequent graphitization treatment step, the silica exerts a confinement effect on the pores of the target carbon support, avoiding the problem of collapse or shrinkage of the pores of the target carbon support during the graphitization treatment; finally, the initial mesoporous carbon material is subjected to alkali washing treatment to remove the silica on the surface and in the pores, obtaining a target carbon support with both high graphitization degree and high mesopore volume, improving the durability and catalytic activity of platinum-carbon catalysts, platinum-alloy catalysts, etc. using it as a support.

[0053] The following are specific embodiments of the present application:

[0054] Example 1:

[0055] S1: Weigh 10 g of carbon black 1. The specific surface area of carbon black 1 is 801 m 2 / g, the mesopore volume is 1.18 cm 3 / g, the proportion of mesopores with a size of 5 nm to 50 nm is 41.2%, and the graphitization degree / defect degree (I D / I G ) is 1.43;

[0056] S2: Disperse carbon black 1 in a 3 mol / L concentrated nitric acid solution, perform reflux treatment at 100 °C for 6 h, filter and wash until neutral, and then perform vacuum drying at 60 °C to obtain a pre-oxidized carbon support;

[0057] S3: Weigh 4 g of the pre-oxidized carbon support obtained in the previous step and disperse it in a 0.5 L water-alcohol solution containing 0.5 mol of lysine. The volume ratio of ethanol to water in the water-alcohol solution is 1:1. Stir in an ice bath. When the pH value of the reaction system does not change within 5 min, adjust the pH of the reaction solution to 13 with a 0.1 mol / L sodium hydroxide solution and start timing. Continue the reaction for 8 h and then stop the reaction. Filter and wash until neutral, and then perform vacuum drying at 60 °C to obtain a functionalized carbon support;

[0058] S4: Weigh 2 g of the functionalized carbon support from the previous step and disperse it in 1 L of a water-alcohol solution with a volume ratio of ethanol to water in the water-alcohol solution being 1:1. While stirring, slowly add tetraethyl orthosilicate drop by drop. Among them, the molar ratio of tetraethyl orthosilicate, ethanol, and water is 1:3:1. After reacting at 60 °C for 24 h, filter and conduct vacuum drying at 60 °C to obtain the target carbon support;

[0059] S5: Place the target carbon support from the previous step in a graphitization furnace. Under an argon atmosphere, heat it to 1200 °C at a rate of 5 °C / min, then heat it to 1500 °C at a rate of 2 °C / min and hold for 1 h. After that, let it cool naturally and purge it clean with argon to obtain the initial mesoporous carbon material;

[0060] S6: Place the initial mesoporous carbon material from the previous step in a 0.2 mol / L sodium hydroxide solution and conduct alkali washing treatment at room temperature for 12 h. Then filter and conduct vacuum drying at 60 °C to obtain the target mesoporous carbon material.

[0061] Example 2:

[0062] The preparation steps of Example 2 are basically the same as those of Example 1, except that carbon black 2 is used in Example 2. The specific surface area of carbon black 2 is 607 m 2 / g, the mesoporous pore volume is 0.9 cm 3 / g, and the proportion of mesopores with a size of 5 nm to 50 nm is 51.5%. The graphitization degree / defect degree (I D / I G ) is 1.61.

[0063] Example 3:

[0064] The preparation steps of Example 3 are basically the same as those of Example 1, except that carbon black 2 is used in Example 3, and lysine in step S3 is replaced by ammonia water.

[0065] Comparative Example 1:

[0066] Weigh 10 g of carbon black 1 and place it in a graphitization furnace. Under an argon atmosphere, heat it to 1200 °C at a rate of 5 °C / min, then heat it to 1500 °C at a rate of 2 °C / min and hold for 1 h. After that, let it cool naturally and purge it clean with argon.

[0067] Table 1 shows the parameters corresponding to each example and comparative example:

[0068] Table 1

[0069]

[0070] By comparing Carbon Black 1, Example 1 and Comparative Example 1, it can be found that compared with the method of directly performing graphitization treatment, for the target carbon carrier obtained by using the preparation method of the graphitized mesoporous carbon carrier of the present application, the confinement effect of silicon dioxide significantly inhibits the shrinkage or collapse of the mesoporous structure, better retains the mesoporous volume of the initial carbon black, and the graphitization degree and specific surface area of the obtained target carbon carrier are still relatively high.

[0071] By comparing Carbon Black 1 and Example 1, as well as Carbon Black 2 and Example 2, it can be found that the preparation method of the graphitized mesoporous carbon carrier provided in the examples of the present application can be applied to different types of carbon black to ensure that the mesoporous volume of the initial carbon black is retained, so as to obtain a target carbon carrier with both high graphitization degree and high mesoporous capacity.

[0072] By comparing Example 2 and Example 3, it can be found that after functionalization with different types of weak alkaline solvents, the corresponding mesopore volume and pore size distribution of the final obtained target carbon carrier are different. It can be seen that the size and distribution of the amorphous silicon dioxide formed by the hydrolysis reaction induced by different types of weak alkaline solvents are different, but the retention of the mesoporous volume and the graphitization degree is still good.

[0073] Those of ordinary skill in the art can understand that the above embodiments are specific examples for implementing the present application. In actual applications, various changes can be made in form and details without departing from the spirit and scope of the present application. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, the protection scope of the present application should be subject to the scope defined by the claims.

Claims

1. A preparation method of a graphitized mesoporous carbon support, characterized in that, Comprising: Providing an initial carbon carrier; Performing a pre-oxidation treatment, dispersing the initial carbon carrier in an oxidizing solution for reflux treatment, filtering, washing and drying to obtain a pre-oxidized carbon carrier; Performing a functionalization treatment on the pre-oxidized carbon carrier, adsorbing or grafting weakly basic functional groups on the surface and pore walls of the pre-oxidized carbon carrier to obtain a functionalized carbon carrier. After dispersing the pre-oxidized carbon carrier in an aqueous alcohol solution containing a weakly basic solvent, adjusting the pH value of the reaction solution to an alkaline condition for reaction, filtering, washing and drying to obtain the functionalized carbon carrier; Performing a hydrolysis reaction on the functionalized carbon carrier and a silicon source to obtain a target carbon carrier, wherein amorphous silica is present in the pores of the target carbon carrier. The hydrolysis reaction includes: dispersing the functionalized carbon carrier in a mixed solution of water and ethanol and dropwise adding the silicon source; Performing a graphitization treatment on the target carbon carrier to obtain an initial mesoporous carbon material; Performing an alkali washing treatment on the initial mesoporous carbon material to remove the silica component in the initial mesoporous carbon material to obtain a target mesoporous carbon material.

2. The preparation method of the graphitized mesoporous carbon support according to claim 1, wherein, In the step of the pre-oxidation treatment, the oxidant in the oxidizing solution is selected from at least one of concentrated nitric acid, concentrated hydrochloric acid, hydrogen peroxide, potassium permanganate, sodium hypochlorite or bromine water; the concentration of the oxidant in the oxidizing solution is 2 mol / L to 4 mol / L.

3. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, In the step of the pre-oxidation treatment, the temperature for reflux treatment is 80 °C to 120 °C, and the time is 4 h to 8 h.

4. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, In the step of the functionalization treatment, the weakly basic solvent is selected from at least one of lysine or ammonia water; the aqueous alcohol solution includes ethanol and water with a volume ratio of 1:(0.5 to 1.5); the concentration of the weakly basic solvent is 0.8 mol / L to 1.2 mol / L.

5. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, The step of the functionalization treatment includes: under the condition of a temperature of 5 °C to 15 °C, dispersing the pre-oxidized carbon carrier in an aqueous alcohol solution containing a weakly basic solvent. If the pH value of the reaction system does not change within 3 min to 6 min, then adjusting the pH value of the reaction solution to 12 to 14 and continuing the reaction for 6 h to 10 h.

6. The preparation method of the graphitized mesoporous carbon support according to claim 5, characterized in that, The reagent used to adjust the pH value of the reaction system is a sodium hydroxide solution with a concentration of 0.05 mol / L to 1.5 mol / L.

7. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, In the step of the hydrolysis reaction, the silicon source is selected from at least one of methyl orthosilicate (TMOS), tetraethyl orthosilicate (TEOS), polyethoxydisiloxane (PEDS), methyltrimethoxysilane (MTMS), methyltriethoxysilane (MTES) or sodium silicate (Na2SiO3).

8. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, The step of the hydrolysis reaction includes: dispersing the functionalized carbon carrier in a mixed solution of water and ethanol with a molar ratio of 1:(2.5 to 3.5) and dropwise adding the silicon source, wherein the molar ratio of the silicon source to water is (0.5 to 1):1; the hydrolysis reaction time is 20 h to 30 h, and the temperature is 40 °C to 80 °C.

9. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, The steps of the graphitization treatment include: placing the target carbon carrier in a graphitization furnace, first heating it at a rate of 3°C / min to 5°C / min to 1000°C to 1300°C; then heating it at a rate of 1°C / min to 2°C / min to 1400°C to 1600°C, and then holding the temperature for 0.5 h to 2 h.

10. The preparation method of the graphitized mesoporous carbon support according to claim 1, characterized in that, The steps of the alkali washing treatment include: dispersing the initial mesoporous carbon material in a sodium hydroxide solution with a concentration of 0.1 mol / L to 0.5 mol / L at 20°C to 25°C and washing for 10 h to 14 h, and obtaining the target mesoporous carbon material through filtration and drying.

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