A phenolic resin-based spherical carbon material and a method for preparing the same

Abstract

The application belongs to the technical field of carbon materials, and specifically provides a phenolic resin-based spherical carbon material and a preparation method thereof, the preparation method comprising the following steps: 1) subjecting alpha-lipoic acid, N-hydroxysuccinimide and N,N'-dicyclohexyl carbodiimide to an activation reaction in a solvent, adding 2-(dimethylamino)ethyl methacrylate to the filtrate after filtration to perform a reaction, then adding 1,4-butane sultone to perform a reaction, and obtaining a betaine derivative through post-treatment; 2) mixing phenol, the betaine derivative, an aqueous formaldehyde solution, polyethylene glycol and ammonia water to perform a polymerization reaction, then adding hexamethylenetetramine to perform a cross-linking and curing reaction, performing solid-liquid separation, washing and drying after the reaction is completed to obtain a precursor, and performing high-temperature carbonization treatment on the precursor under an inert atmosphere, so that the phenolic resin-based spherical carbon material is obtained after cooling. The carbon material prepared by the application has the advantages of good sphericity, perfect pore structure, uniform particle size and high specific surface area.

Description

Technical Field

[0001] This application belongs to the field of carbon materials technology, and in particular relates to a phenolic resin-based spherical carbon material and its preparation method. Background Technology

[0002] Spherical carbon materials, as important functional carbon materials, possess characteristics such as regular spherical morphology, controllable particle size distribution, good flowability, high bulk density, and excellent mechanical strength, showing broad application prospects in adsorption separation, catalyst supports, electrode materials, chromatographic packing materials, and drug sustained release. In particular, in recent years, with the increasing demand for high-performance porous carbon materials in the energy and environmental sectors, the development of spherical carbon materials with controllable structure and excellent performance has become an important direction in carbon materials research.

[0003] Currently, the preparation methods for spherical carbon materials are mainly divided into two categories: one category uses asphalt, polymer resins, etc. as precursors, and first prepares spherical precursors through emulsification, suspension polymerization, spray drying, etc., and then obtains spherical carbon materials through stabilization, carbonization, activation, and other processes; the other category uses biomass or other carbon sources as raw materials and directly prepares spherical carbon materials through hydrothermal carbonization and other methods. Phenolic resin, as an important synthetic polymer material, is considered one of the ideal precursors for preparing high-performance spherical carbon materials due to its advantages such as high carbon content, good thermal stability, tunable crosslinking structure, and high carbonization yield. In existing technologies, the preparation of phenolic resin-based spherical carbon materials usually adopts the following methods: suspension polymerization: linear or thermosetting phenolic resin or its prepolymer is dispersed in an aqueous or oil-phase medium containing a dispersant, and spherical droplets are formed by mechanical stirring, followed by heating, curing, separation, drying, carbonization, and other steps to obtain spherical carbon materials. This method is relatively mature, but it has the following problems: sphericity is extremely sensitive to process parameters such as stirring speed, type and concentration of dispersant, and oil-to-water ratio; the particle size distribution is wide and difficult to control precisely; droplets are prone to deformation or adhesion during curing; a large amount of surfactant or dispersant is required, the post-processing is complex, and the use of organic solvents can easily cause environmental pollution. Emulsion / microemulsion method: By forming a stable oil-in-water or water-in-oil emulsion system, phenolic resin undergoes a polymerization reaction within the emulsion droplets to form spherical microparticles. This method can prepare submicron to nanoscale spherical carbon materials, but it suffers from complex preparation processes, low yields, difficulty in completely removing emulsifiers, and high solvent consumption, making large-scale production difficult. Hydrothermal method: Using phenolic compounds and aldehyde compounds as raw materials, phenolic resin spheres are directly generated under hydrothermal conditions, and then carbonized to obtain spherical carbon materials. This method is relatively simple to operate, but the hydrothermal reaction process usually requires a long reaction time, and the uniformity of the particle size of the obtained spherical material needs to be improved. At the same time, the hydrothermal mother liquor contains a large number of unreacted monomers and organic by-products, and the wastewater treatment cost is high.

[0004] Furthermore, existing phenolic resin-based spherical carbon materials suffer from limitations such as limited pore structure control, difficulty in achieving both sphericity and particle size uniformity, and insufficient mechanical strength. Therefore, there is an urgent need to develop green and environmentally friendly phenolic resin-based spherical carbon materials with good sphericity, uniform particle size, controllable pore structure, and high mechanical strength to meet the pressing demand for high-performance spherical carbon materials in high-end applications. Summary of the Invention

[0005] To address the above-mentioned problems, this application provides a phenolic resin-based spherical carbon material and its preparation method.

[0006] This application first provides a method for preparing phenolic resin-based spherical carbon materials, comprising the following steps: 1) α-Lipoic acid, N-hydroxysuccinimide and N,N'-dicyclohexylcarbodiimide were activated in a solvent, filtered, and 2-(dimethylamino)ethyl methacrylate was added to the filtrate for reaction. Then 1,4-butyrosulactone was added for reaction. After post-treatment, betaine derivatives were obtained. 2) Phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia are mixed and polymerized. Then, hexamethylenetetramine is added to carry out cross-linking and curing reaction. After the reaction is completed, the precursor is obtained by solid-liquid separation, washing and drying. The precursor is then carbonized at high temperature under an inert atmosphere and cooled to obtain the final product.

[0007] Furthermore, in step 1), the mass ratio of α-lipoic acid, N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, 2-(dimethylamino)ethyl methacrylate and 1,4-butyrosulactone is 1:(0.2-0.5):(0.5-1.0):(0.4-0.8):(0.3-0.6).

[0008] Furthermore, in step 1), the solvent is at least one of tetrahydrofuran, dichloromethane, or N,N-dimethylformamide.

[0009] Furthermore, in step 1), the activation reaction and the reaction after adding 2-(dimethylamino)ethyl methacrylate are both carried out at room temperature, and the reaction after adding 1,4-butyrolactone is carried out at 30-60°C.

[0010] Furthermore, in step 2), the mass ratio of phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia is 1:(0.1-0.5):(0.8-1.5):(0.02-0.1):(0.03-0.1).

[0011] Furthermore, in step 2), the polyethylene glycol is at least one of polyethylene glycol-2000, polyethylene glycol-4000, polyethylene glycol-6000, or polyethylene glycol-8000; And / or, in step 2), oat β-glucan is added along with polyethylene glycol.

[0012] Furthermore, in step 2), the polymerization reaction is carried out at a temperature of 80-95°C for 8-16 hours. And / or, in step 2), the temperature of the crosslinking curing reaction is 90-100℃ and the time is 1-5h.

[0013] Furthermore, in step 2), the mass ratio of phenol to hexamethylenetetramine is 1:(0.02-0.08).

[0014] Furthermore, in step 2), the high-temperature carbonization process is as follows: the temperature is increased to 1000-1500℃ at a heating rate of 1-10℃ / min, and held at this temperature for 1-5 hours. And / or, in step 2), the inert atmosphere is one or more of nitrogen, argon, or helium.

[0015] This application also provides a phenolic resin-based spherical carbon material, which is prepared by the above-described preparation method.

[0016] Compared with the prior art, this application has the following beneficial effects: This application introduces a betaine derivative into a phenolic polymerization system. The methacrylate group at one end of this derivative can participate in the phenolic condensation reaction and be grafted onto the phenolic resin molecular chain. The zwitterionic structure formed by the sulfonate and quaternary ammonium salt groups at the other end significantly improves the monodispersity and sphericity of the precursor microspheres, reducing adhesion and deformation problems. Under ammonia catalysis, the phenolic oligomer grafted with the betaine derivative self-assembles in a water / alcohol system to form stable micelles or droplets. The addition of polyethylene glycol further modulates the viscosity and interfacial tension of the system. As polymerization and cross-linking reactions proceed, these micelles or droplets solidify in situ to form precursor microspheres with a regular spherical morphology. In the subsequent high-temperature carbonization process, the organic components in the precursor pyrolyze, ultimately forming a carbon material with good sphericity, well-developed pore structure, uniform particle size, and high specific surface area. In addition, when carbon materials are used as electrode materials, derivatives can introduce sulfur atoms into the carbon materials, which can significantly increase the interlayer spacing of the carbon materials, improve porosity and specific surface area, and facilitate the insertion, extraction and diffusion of sodium ions. Moreover, intrinsic defects can be introduced to provide additional uniformly dispersed active sites, thereby improving sodium storage capacity and stability. Attached Figure Description

[0017] Figure 1 This is a SEM image of the carbon material in Example 2 of this application.

[0018] Figure 2 This is a SEM image of the carbon material in control group 1 of this application.

[0019] Figure 3 This is a SEM image of the carbon material in control group 2 of this application. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0022] When using “including,” “having,” and “contains” as described herein, the intention is to cover non-exclusive inclusion, unless an explicit qualifying term such as “only,” “consisting of,” etc., is used, in which case another component may be added.

[0023] The terms "preferred," "more preferably," "better," and "even better" used in this application refer to embodiments of this application that provide certain beneficial effects under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the description of one or more preferred embodiments does not imply that other embodiments are unavailable, nor is it intended to exclude other embodiments from the scope of this application. That is, in this application, "preferred," "more preferably," "better," and "even better" are merely descriptions of implementations or embodiments with better effects, but do not constitute a limitation on the scope of protection of this application.

[0024] In this application, terms such as "further," "even more," and "particularly" are used for descriptive purposes and to indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0025] In this application, "at least one" means one or more, such as one, two, or more. "Multiple" or "several" means at least two, such as two, three, etc., and "multi-layered" means at least two layers, such as two layers, three layers, etc., unless otherwise explicitly specified. In the description of this application, "several" means at least one, such as one, two, etc., unless otherwise explicitly specified.

[0026] When a numerical range is disclosed herein, the range is considered continuous and includes the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be combined. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0027] Unless otherwise specified, all steps in this application may be performed sequentially or randomly. For example, the method comprising steps (a) and (b) indicates that the method may include steps (a) and (b) performed sequentially, or it may include steps (b) and (a) performed sequentially. For example, the mention that the method may also include step (c) indicates that step (c) may be added to the method in any order; for example, the method may include steps (a), (b), and (c), or it may include steps (a), (c), and (b), or it may include steps (c), (a), and (b), etc. Unless otherwise stated, singular terms may include plural forms and should not be construed as having a quantity of one.

[0028] In this application, "above" or "below" includes the number itself. For example, "below 1" includes 1.

[0029] In this application, room temperature refers to 0~40℃, including but not limited to 10~40℃, or further to 20~30℃.

[0030] This application, based on extensive experimental research, provides a method for preparing phenolic resin-based spherical carbon materials, comprising the following steps: 1) α-Lipoic acid, N-hydroxysuccinimide and N,N'-dicyclohexylcarbodiimide were activated in a solvent, filtered, and 2-(dimethylamino)ethyl methacrylate was added to the filtrate for reaction. Then 1,4-butyrosulactone was added for reaction. After post-treatment, betaine derivatives were obtained. 2) Phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia are mixed and polymerized. Then, hexamethylenetetramine is added to carry out cross-linking and curing reaction. After the reaction is completed, the precursor is obtained by solid-liquid separation, washing and drying. The precursor is then carbonized at high temperature under an inert atmosphere and cooled to obtain the final product.

[0031] Furthermore, in step 1), the mass ratio of α-lipoic acid, N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, 2-(dimethylamino)ethyl methacrylate and 1,4-butyrosulactone is 1:(0.2-0.5):(0.5-1.0):(0.4-0.8):(0.3-0.6).

[0032] In some specific embodiments, in step 1), the mass ratio of α-lipoic acid, N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, 2-(dimethylamino)ethyl methacrylate, and 1,4-butyrosulactone can be 1:0.2:0.5:0.4:0.3, 1:0.25:0.5:0.4:0.3, 1:0.3:0.5:0.4:0.3, or 1:0.35:0.5:0.4 :0.3, 1:0.4:0.5:0.4:0.3, 1:0.45:0.5:0.4:0.3, 1:0.5:0.5:0.4:0.3, 1:0.2:0.6:0.4:0.3, 1:0.25:0.7:0.4:0.3, 1:0.3:0.8:0.4:0.3, 1:0.35:0.9:0.4:0.3, 1:0.4:1:0.4:0.3, 1 :0.45:1:0.4:0.3, 1:0.5:1:0.4:0.3, 1:0.2:0.6:0.45:0.3, 1:0.25:0.7:0.5:0.3, 1:0.3:0.8:0.55:0.3, 1:0.35:0.9:0.6:0.3, 1:0.4:1:0.65:0.3, 1:0.45:1:0.7:0.3, 1:0.5:1:0 The following ratios are commonly used: 0.8:0.3, 1:0.5:1:0.4:0.35, 1:0.2:0.6:0.45:0.4, 1:0.25:0.7:0.5:0.45, 1:0.3:0.8:0.55:0.5, 1:0.35:0.9:0.6:0.55, 1:0.4:1:0.65:0.6, 1:0.45:1:0.7:0.6, and 1:0.5:1:0.8:0.6. Under normal circumstances, in step 1), a mass ratio of α-lipoic acid, N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, 2-(dimethylamino)ethyl methacrylate, and 1,4-butyrosyllactone of 1:0.35:0.66:0.57:0.45 yields the best technical results.

[0033] Furthermore, in step 1), the solvent is at least one of tetrahydrofuran, dichloromethane, or N,N-dimethylformamide.

[0034] In some specific embodiments, when tetrahydrofuran is used as the solvent in step 1), better experimental results can be obtained.

[0035] Furthermore, in step 1), the activation reaction and the reaction after adding 2-(dimethylamino)ethyl methacrylate are both carried out at room temperature, and the reaction after adding 1,4-butyrolactone is carried out at 30-60°C.

[0036] Furthermore, in step 2), the mass ratio of phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia is 1:(0.1-0.5):(0.8-1.5):(0.02-0.1):(0.03-0.1).

[0037] In some specific embodiments, in step 2), the mass ratio of phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol, and ammonia can be 1:0.1:0.8:0.02:0.03, 1:0.15:0.8:0.02:0.03, 1:0.2:0.8:0.02:0.03, 1:0.25:0.8:0.02:0.03, 1:0.3:0.8:0.02:0.03, 1:0.35:0.8:0.02:0.03, 1:0.4:0.8:0.02:0.03, or 1:0.45:0.8:0. .02:0.03, 1:0.5:0.8:0.02:0.03, 1:0.1:0.85:0.02:0.03, 1:0.15:0.9:0.02:0.03, 1:0.2:0.95:0.02:0.03, 1:0.25:1:0.02:0.03, 1:0.3:1.05:0.02:0.03, 1:0.35:1.1:0.02:0.03, 1:0.4:1.2:0.02:0.03, 1:0.45:1.3:0.02:0.03, 1:0.5:1.5:0.0 2:0.03, 1:0.5:0.8:0.03:0.03, 1:0.1:0.85:0.04:0.03, 1:0.15:0.9:0.05:0.03, 1:0.2:0.95:0.06:0.03, 1:0.25:1:0.07:0.03, 1:0.3:1.05:0.08:0.03, 1:0.35:1.1:0.09:0.03, 1:0.4:1.2:0.1:0.03, 1:0.45:1.3:0.1:0.03, 1:0.5:1.5:0.1:0. 03、1:0.5:0.8:0.03:0.04、1:0.1:0.85:0.04:0.05、1:0.15:0.9:0.05:0.06、1:0.2:0.95:0.06:0.065、1:0.25:1:0.07:0.07、1:0.3:1.05:0.08:0.075、1:0.35:1.1:0.09:0.08、1:0.4:1.2:0.1:0.085、1:0.45:1.3:0.1:0.09、1:0.5:1.5:0.1:0.1、 Under normal circumstances, when the mass ratio of phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia in step 2) is 1:0.25:1.125:0.0525:0.063, better experimental results can be obtained.

[0038] Furthermore, in step 2), the polyethylene glycol is at least one of polyethylene glycol-2000, polyethylene glycol-4000, polyethylene glycol-6000, or polyethylene glycol-8000; And / or, in step 2), oat β-glucan is added along with polyethylene glycol.

[0039] In some specific embodiments, when polyethylene glycol-6000 is used in step 2), the experimental results are better.

[0040] In some specific embodiments, in step 2), the mass ratio of polyethylene glycol to oat β-glucan is 1:(0.05-0.15), for example, it can be 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09, 1:0.10, 1:0.11, 1:0.12, 1:0.13, 1:0.14, or 1:0.15. More preferably, when the mass ratio of polyethylene glycol to oat β-glucan is 1:0.12, the stability of the system can be improved by the long polysaccharide chain, and the obtained microsphere precursor has good sphericity and more uniform particle size distribution.

[0041] Furthermore, in step 2), the polymerization reaction is carried out at a temperature of 80-95°C for 8-16 hours. And / or, in step 2), the temperature of the crosslinking curing reaction is 90-100℃ and the time is 1-5h.

[0042] In some specific embodiments, in step 2), the polymerization reaction temperature can be 80-85℃, 85-90℃, or 90-95℃, and the time can be 8-10h, 9-12h, 10-15h, 12-13h, or 12-16h. More preferably, a polymerization reaction temperature of 85℃ and a time of 12h can achieve better technical results.

[0043] Furthermore, in step 2), the mass ratio of phenol to hexamethylenetetramine is 1:(0.02-0.08).

[0044] In some specific embodiments, in step 2), the mass ratio of phenol to hexamethylenetetramine can be 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, or 1:0.08. Generally, a mass ratio of phenol to hexamethylenetetramine of 1:0.05 or 1:0.06 in step 2) yields better results.

[0045] Furthermore, in step 2), the high-temperature carbonization process is as follows: the temperature is increased to 1000-1500℃ at a heating rate of 1-10℃ / min, and held at this temperature for 1-5 hours. In some specific embodiments, the high-temperature carbonization process in step 2) involves heating at rates of 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min, and 10℃ / min to 1000℃, 1100℃, 1200℃, 1300℃, 1400℃, and 1500℃, respectively, and holding at these temperatures for 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, and 5h. More preferably, when the temperature is raised to 1300℃ at a rate of 5℃ / min and held at this temperature for 2h, the resulting product exhibits better performance.

[0046] And / or, in step 2), the inert atmosphere is one or more of nitrogen, argon, or helium.

[0047] This application also provides a phenolic resin-based spherical carbon material, which is prepared by the above-described preparation method.

[0048] The present application will be further illustrated by the following examples, but these examples do not limit the scope of the present application.

[0049] When numerical ranges are given in the embodiments, it should be understood that, unless otherwise stated in this application, both endpoints of each numerical range and any value between the two endpoints may be selected. Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. All reagents or instruments whose manufacturers are not specified are conventional products that can be purchased commercially. In addition to the specific methods, equipment, and materials used in the embodiments, based on the knowledge of the prior art possessed by one of ordinary skill in the art and the description in this application, any prior art methods, equipment, and materials similar to or equivalent to those described, used, or made by the methods, equipment, and materials in the embodiments of this application may be used to implement this application.

[0050] Example 1 The preparation method of the phenolic resin-based spherical carbon material in this embodiment includes the following steps: 1) Dissolve 50g of α-lipoic acid in 500mL of THF, add 17.3g of N-hydroxysuccinimide and 33g of N,N'-dicyclohexylcarbodiimide, stir and activate at room temperature, filter, add 28.5g of 2-(dimethylamino)ethyl methacrylate to the filtrate, stir and react at room temperature, after the reaction is complete, add 22.5g of 1,4-butyrosulactone, stir and react at 40℃, filter, concentrate the obtained filtrate under reduced pressure, remove the solvent to obtain betaine derivative; 2) Add 20g phenol, 5g betaine derivative, 22.5g formaldehyde aqueous solution (analytical grade, mass fraction 37%), 1.05g polyethylene glycol 6000, and 1.275g ammonia to a 250mL flask. After mixing evenly, heat to 85℃ and stir for 12h. Then add 1g hexamethylenetetramine, raise the temperature to 95℃, and continue stirring for 3h. Centrifuge the resulting reaction solution, take the precipitate, wash it with deionized water and ethanol, and then dry it in an oven at 80℃ to obtain the precursor. Transfer the precursor to a tube furnace and heat it to 1300℃ in an argon atmosphere at a heating rate of 5℃ / min. Hold it at this temperature for 2h, and then cool it to room temperature to obtain the final product.

[0051] Example 2 The preparation method of the phenolic resin-based spherical carbon material in this embodiment includes the following steps: 1) Dissolve 50g of α-lipoic acid in 500mL of THF, add 17.3g of N-hydroxysuccinimide and 33g of N,N'-dicyclohexylcarbodiimide, stir and activate at room temperature, filter, add 28.5g of 2-(dimethylamino)ethyl methacrylate to the filtrate, stir and react at room temperature, after the reaction is complete, add 22.5g of 1,4-butyrosulactone, stir and react at 40℃, filter, concentrate the obtained filtrate under reduced pressure, remove the solvent to obtain betaine derivative; 2) Add 20g phenol, 5g betaine derivative, 22.5g formaldehyde aqueous solution (analytical grade, mass fraction 37%), 1.05g polyethylene glycol 6000, 0.126g oat β-glucan, and 1.275g ammonia to a 250mL flask. After mixing evenly, heat to 85℃ and stir for 12h. Then add 1g hexamethylenetetramine, raise the temperature to 95℃, and continue stirring for 3h. Centrifuge the resulting reaction solution, take the precipitate, wash it with deionized water and ethanol, and then dry it in an oven at 80℃ to obtain the precursor. Transfer the precursor to a tube furnace and heat it to 1300℃ in an argon atmosphere at a heating rate of 5℃ / min. Hold it at this temperature for 2h, and then cool it to room temperature to obtain the final product.

[0052] Control group 1 The preparation method of the phenolic resin-based spherical carbon material in this control group includes the following steps: Add 20g phenol, 22.5g formaldehyde aqueous solution (analytical grade, 37% by mass), 1.05g polyethylene glycol 6000, and 1.275g ammonia to a 250mL flask. After mixing thoroughly, heat to 85℃ and stir for 12h. Then add 1g hexamethylenetetramine, raise the temperature to 95℃, and continue stirring for 3h. Centrifuge the resulting reaction solution, take the precipitate, wash it with deionized water and ethanol, and then dry it in an oven at 80℃ to obtain the precursor. Transfer the precursor to a tube furnace and heat it to 1300℃ in an argon atmosphere at a heating rate of 5℃ / min. Hold it at this temperature for 2h, and then cool it to room temperature to obtain the final product.

[0053] Control group 2 The preparation method of the phenolic resin-based spherical carbon material in this control group includes the following steps: Add 20g phenol, 5g dodecyl betaine, 22.5g formaldehyde aqueous solution (analytical grade, 37% by mass), 1.05g polyethylene glycol 6000, and 1.275g ammonia to a 250mL flask. After mixing thoroughly, heat to 85℃ and stir for 12h. Then add 1g hexamethylenetetramine, raise the temperature to 95℃, and continue stirring for 3h. Centrifuge the resulting reaction solution, wash the precipitate with deionized water and ethanol, and then dry it in an oven at 80℃ to obtain the precursor. Transfer the precursor to a tube furnace and heat it to 1300℃ in an argon atmosphere at a heating rate of 5℃ / min. Hold it at this temperature for 2h, and then cool it to room temperature to obtain the final product.

[0054] Performance testing 1. The specific surface area, pore volume, pore diameter and pore area of ​​the carbon material in Example 2 were tested using a BSD-660S A3S physical gas adsorption analyzer. The comprehensive test results are shown in Tables 1 to 3.

[0055] Table 1. Specific surface area test data of carbon materials in Example 2

[0056] Table 2. Test data of adsorption pore volume, pore size, and pore area of ​​the carbon material in Example 2.

[0057] Table 3 Test data of desorption pore volume, pore diameter and pore area of ​​carbon material in Example 2

[0058] 2. The carbon material of Example 2 was analyzed by a BT-9300LD dry laser particle size analyzer. The test results are shown in Table 4.

[0059] Table 4. Particle size analysis test data of carbon materials in Example 2

[0060] 3. The morphology of the carbon materials in Example 2 and Control Groups 1-2 was tested using scanning electron microscopy. The test results are as follows: Figures 1-3 As shown.

[0061] Combined with appendix Figures 1-3 It can be seen that the carbon material prepared in this application has the characteristics of good sphericity, perfect pore structure, uniform particle size and high specific surface area. The carbon material of control group 1 is severely adhered and has uneven particle size. The carbon material of control group 2 also shows adhesion and poor particle size uniformity.

[0062] Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A method for preparing a phenolic resin-based spherical carbon material, characterized in that: Includes the following steps: 1) α-Lipoic acid, N-hydroxysuccinimide and N,N'-dicyclohexylcarbodiimide were activated in a solvent, filtered, and 2-(dimethylamino)ethyl methacrylate was added to the filtrate for reaction. Then 1,4-butyrosulactone was added for reaction. After post-treatment, betaine derivatives were obtained. 2) Phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia are mixed and polymerized. Then, hexamethylenetetramine is added to carry out cross-linking and curing reaction. After the reaction is completed, the precursor is obtained by solid-liquid separation, washing and drying. The precursor is then carbonized at high temperature under an inert atmosphere and cooled to obtain the final product.

2. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 1), the mass ratio of α-lipoic acid, N-hydroxysuccinimide, N,N'-dicyclohexylcarbodiimide, 2-(dimethylamino)ethyl methacrylate and 1,4-butyrosulactone is 1:(0.2-0.5):(0.5-1.0):(0.4-0.8):(0.3-0.6).

3. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 1), the solvent is at least one of tetrahydrofuran, dichloromethane, or N,N-dimethylformamide.

4. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 1), the activation reaction and the reaction after adding 2-(dimethylamino)ethyl methacrylate are both carried out at room temperature, and the reaction after adding 1,4-butyrosine lactone is carried out at 30-60°C.

5. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 2), the mass ratio of phenol, betaine derivative, formaldehyde aqueous solution, polyethylene glycol and ammonia is 1:(0.1-0.5):(0.8-1.5):(0.02-0.1):(0.03-0.1).

6. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 2), polyethylene glycol is at least one of polyethylene glycol-2000, polyethylene glycol-4000, polyethylene glycol-6000, or polyethylene glycol-8000. And / or, in step 2), oat β-glucan is added along with polyethylene glycol.

7. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 2), the polymerization reaction is carried out at a temperature of 80-95℃ for 8-16 hours. And / or, in step 2), the temperature of the crosslinking curing reaction is 90-100℃ and the time is 1-5h.

8. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 2), the mass ratio of phenol to hexamethylenetetramine is 1:(0.02-0.08).

9. The method for preparing phenolic resin-based spherical carbon material according to claim 1, characterized in that: In step 2), the high-temperature carbonization process is as follows: the temperature is increased to 1000-1500℃ at a heating rate of 1-10℃ / min, and then held at this temperature for 1-5 hours. And / or, in step 2), the inert atmosphere is one or more of nitrogen, argon, or helium.

10. A phenolic resin-based spherical carbon material, characterized in that: It is prepared by any one of the preparation methods described in claims 1-9.

Images