CN113582159A - High-capacitance porous carbon material and preparation method thereof - Google Patents

High-capacitance porous carbon material and preparation method thereof Download PDF

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CN113582159A
CN113582159A CN202111146847.7A CN202111146847A CN113582159A CN 113582159 A CN113582159 A CN 113582159A CN 202111146847 A CN202111146847 A CN 202111146847A CN 113582159 A CN113582159 A CN 113582159A
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capacitance
porous carbon
carbon material
activator
powder
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CN113582159B (en
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张波
温峤
李德军
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Tianjin University
Tianjin Normal University
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    • CCHEMISTRY; METALLURGY
    • C01INORGANIC CHEMISTRY
    • C01BNON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
    • C01B32/00Carbon; Compounds thereof
    • C01B32/05Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01GCAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22Electrodes
    • H01G11/30Electrodes characterised by their material
    • H01G11/32Carbon-based
    • H01G11/34Carbon-based characterised by carbonisation or activation of carbon
    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01GCAPACITORS; CAPACITORS, RECTIFIERS, DETECTORS, SWITCHING DEVICES, LIGHT-SENSITIVE OR TEMPERATURE-SENSITIVE DEVICES OF THE ELECTROLYTIC TYPE
    • H01G11/00Hybrid capacitors, i.e. capacitors having different positive and negative electrodes; Electric double-layer [EDL] capacitors; Processes for the manufacture thereof or of parts thereof
    • H01G11/22Electrodes
    • H01G11/30Electrodes characterised by their material
    • H01G11/32Carbon-based
    • H01G11/44Raw materials therefor, e.g. resins or coal

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  • Chemical & Material Sciences (AREA)
  • Power Engineering (AREA)
  • Materials Engineering (AREA)
  • Microelectronics & Electronic Packaging (AREA)
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  • Inorganic Chemistry (AREA)
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Abstract

The invention provides a high-capacitance porous carbon material and a preparation method thereof, wherein the preparation method comprises the following steps: s1: adding activator powder into the mesocarbon microbead liquid raw material, melting the activator at the temperature of 250-350 ℃, and uniformly mixing the melted activator with the liquid raw material to obtain a mixed material; s2: continuously heating the mixed material to 450-550 ℃, and keeping the temperature for 4-16h to generate the mesocarbon microbead composite material uniformly doped with the molecular activator; s3: and (4) washing the composite material obtained in the step (S2), separating out a solid, drying, and activating the dried solid at 800-1000 ℃ to obtain the high-capacitance porous carbon material. According to the method, the activating agent is uniformly mixed into the mesocarbon microbeads according to the molecular size, and then high-temperature activation treatment is directly carried out, so that the high-capacitance porous carbon material with uniform pore distribution and stable structure is obtained, the pore volume of the carbon material is effectively improved, the electrochemical performance of the carbon material is improved, and meanwhile, the using amount of the activating agent is greatly reduced.

Description

High-capacitance porous carbon material and preparation method thereof
Technical Field
The invention belongs to the field of electrode material preparation, and particularly relates to a high-capacitance porous carbon material and a preparation method thereof.
Background
The current commercialized electrode material for the super capacitor mainly comprises graphite carbon. In order to further improve the performance of the super capacitor, how to stably prepare the electrode material with high specific surface area becomes a hotspot of related researches.
The porous carbon material has huge internal surface area and higher pore volume, and the properties also determine the low density, and the regular arrangement of the carbon leads to higher mechanical strength. In addition, due to the inactivity of carbon atoms, the carbon atoms have various structural performance advantages such as good surface chemical inertness, excellent conductivity and the like, in recent years, porous carbon materials are receiving more and more attention, and corresponding reports are continuously growing. The porous carbon is widely applied to the fields of adsorption, separation, catalysis, electrochemical capacitors and the like, has wide application prospect, and the precursor for preparing the carbon material is cheap and easy to obtain, such as wood and petroleum refining products, even plant straws, husks, coal and the like can be used as carbon sources of the carbon material. With the further development of research in recent years, researchers continuously improve the original synthesis technology in order to further improve the performance of the porous carbon, and promote the development of the porous carbon so that the porous carbon has more perfect practical performance. Through continuous development and research for many years, a large number of novel porous carbon materials with adjustable morphology structures, size distribution, pore sizes, pore shapes and the like are continuously synthesized successfully.
With the continuous expanded application of porous carbon materials in various fields, people have increasingly high requirements on the morphology, pore size, surface chemical properties and the like of porous carbon materials. Therefore, more suitable synthesis methods are continuously sought to meet the standards sought by porous carbon materials. To date, significant progress has been made in the field of synthesis of porous carbon materials.
The activation method has wide application range, is suitable for the preparation process of the porous carbon material, has wide pore size distribution range, is distributed in the micropore and mesopore range, and is suitable for mass production. The activation method is a method in which different types of activators are mixed with a carbon material and react with carbon atoms to change the arrangement of the carbon atoms, the partially reacted carbon atoms are gasified or exfoliated, and the spaces left by the carbon atoms removed by the reaction form a large number of pore gaps, thereby increasing the specific surface area and pore volume of the material.
Disclosure of Invention
In view of the above, the present invention provides a high-capacitance porous carbon material and a preparation method thereof, aiming to overcome the defects in the prior art.
In order to achieve the purpose, the technical scheme of the invention is realized as follows:
a preparation method of a high-capacitance porous carbon material comprises the following steps:
s1: adding activator powder into the mesocarbon microbead liquid raw material, melting the activator at the temperature of 250-350 ℃, and uniformly mixing the melted activator with the mesocarbon microbead liquid raw material to obtain a mixed material;
s2: continuously heating the mixed material to 450-550 ℃, and keeping the temperature for 4-16h to generate the mesocarbon microbead composite material uniformly doped with the molecular activator;
s3: and (4) washing the composite material obtained in the step (S2), separating out a solid, drying, and activating the dried solid at 800-1000 ℃ to obtain the high-capacitance porous carbon material.
Preferably, the activator powder is added in an amount of 20 to 50% (w/w) based on the total mass of the carbon raw material.
Preferably, the mesocarbon microbeads liquid raw material is one or a mixture of more of coal pitch, coal tar, petroleum pitch, heavy oil and ethylene tar.
Preferably, the activator powder is NaOH powder, KOH powder, Na2CO3Powder, K2CO3Powder, NaHCO3One or a mixture of several of the powders.
Preferably, the activator is NaOH powder and/or KOH powder.
The invention also provides the high-capacitance porous carbon material prepared by the method, and the specific surface area of the high-capacitance porous carbon material is 1400 m2/g-2000 m2The specific capacitance is 117F/g-152F/g.
The high-capacitance porous carbon material is applied to preparation of electrode materials of super capacitors.
Compared with the prior art, the invention has the following advantages:
(1) the preparation method comprises the steps of adding activator powder into a liquid raw material of the mesocarbon microbeads, heating and keeping at a constant temperature, enabling the activator to be molten and uniformly dispersed in the mesocarbon microbeads in a molecular size, carrying out polycondensation with polycyclic aromatic molecules in the raw material to generate a composite material of the mesocarbon microbeads uniformly doped with the activator, and heating the composite material of the mesocarbon microbeads doped with the activator for activation treatment to obtain the porous carbon material with uniform pore distribution and stable structure. Compared with the traditional activation process, the method has the advantages of uniform pores, larger comparative area, high activation success rate, excellent electrochemical performance and the like.
(2) The invention overcomes the defects of relatively low success rate of direct activation and low specific surface area of the preparation method in the prior art, and can prepare the product with the specific surface area of 1400 m2G to 2000m2A high-capacitance porous carbon material having a specific capacitance of 117F/g to 152F/g.
Drawings
Fig. 1 is an SEM photograph of a high-capacitance porous carbon material prepared in example 1 of the present invention;
fig. 2 is an SEM photograph of the high-capacitance porous carbon material prepared in example 2 of the present invention;
fig. 3 is an SEM photograph of the high-capacitance porous carbon material prepared in example 3 of the present invention;
fig. 4 is an SEM photograph of the high-capacitance porous carbon material prepared in example 4 of the present invention;
fig. 5 is an SEM photograph of a porous carbon material prepared in comparative example 1 using a conventional direct activation method.
Detailed Description
Unless defined otherwise, technical terms used in the following examples have the same meanings as commonly understood by one of ordinary skill in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods are conventional methods unless otherwise specified.
The invention will be described in detail with reference to the following examples.
Example 1
Firstly, 200 g of NaOH powder is added into 1kg of petroleum asphalt, the temperature is raised to 250 ℃, the high-speed stirring is carried out for 1h, then the temperature is raised to 450 ℃, the constant temperature is kept for 4h, washing is carried out by using wash oil, the solid obtained by separation is dried to obtain the composite material of the mesocarbon microbeads uniformly doped with the molecular activator, and then the composite material is activated at 800 ℃ to obtain the composite material with the specific surface area of about 1500m2As shown in the SEM photograph of FIG. 1, the specific capacitance of the high-capacitance porous carbon material reached 117F/g.
Example 2
Firstly, adding 300g of KOH powder into 1kg of petroleum asphalt, heating to 250 ℃, stirring at a high speed for 1.5h, then heating to 500 ℃, keeping the temperature for 8h, washing by using washing oil, separating to obtain a solid, drying to obtain a composite material of the mesophase carbon microsphere uniformly doped with a molecular activator, and activating at 800 ℃ to obtain a composite material with a specific surface area of about 1600m2The SEM photograph of the high-capacitance porous carbon material in/g is shown in FIG. 2.
Example 3
Firstly adding 250 g of NaOH powder and 250 g of KOH powder into a mixture of 0.25kg of coal tar pitch, 0.5kg of petroleum pitch and 0.25kg of heavy oil, heating to 350 ℃, stirring at a high speed for 2h, then heating to 550 ℃, keeping the temperature for 10h, washing by using washing oil, separating to obtain a solid, drying to obtain a composite material of the mesocarbon microbeads uniformly doped with molecular activators, and activating at 900 ℃ to obtain the mesocarbon microbeads with the specific surface area of about 1900m2The SEM photograph of the high-capacitance porous carbon material in/g is shown in FIG. 3.
Example 4
Firstly, 200 g of NaOH powder and 300g of KOH powder are added into a mixture of 0.5kg of coal tar and 0.5kg of ethylene tar, the temperature is raised to 350 ℃, the mixture is stirred at a high speed for 2.5h, then the temperature is raised to 550 ℃, the temperature is kept constant for 16h, washing is carried out by using washing oil, a solid is obtained by separation and drying, the composite material of the mesocarbon microbeads uniformly doped with the molecular activator is obtained, and then the composite material is activated at 1000 ℃ to obtain the mesocarbon microbeads with the specific surface area of about 2000m2The SEM photograph of the high-capacitance porous carbon material in/g is shown in FIG. 4.
Example 5
Firstly, 200 g of KOH powder and 200 g of NaOH powder are added into 1kg of petroleum asphalt, the temperature is raised to 250 ℃, the mixture is stirred at a high speed for 1.5h, then the temperature is raised to 500 ℃, the temperature is kept for 8h, washing is carried out by using wash oil, a solid is obtained by separation and dried, the composite material of the mesocarbon microbeads uniformly doped with molecular activators is obtained, and then activation treatment is carried out at 800 ℃ to obtain the composite material with the specific surface area of about 1800m2The specific capacitance of the high-capacitance porous carbon material reaches 138F/g.
Example 6
Firstly, adding 500 g of KOH powder into 1kg of petroleum asphalt, heating to 250 ℃, stirring at a high speed for 1.5h, then heating to 500 ℃, keeping the temperature for 8h, washing by using washing oil, separating to obtain a solid, drying to obtain a composite material of the mesocarbon microbeads uniformly doped with the molecular activator, and activating at 800 ℃ to obtain the composite material with the specific surface area of about 1850m2The specific capacitance of the high-capacitance porous carbon material reaches 152F/g.
Comparative example 1
Firstly, 600g of KOH powder is added into 1kg of petroleum asphalt, the temperature is raised to 250 ℃, the high-speed stirring is carried out for 1.5h, then the temperature is raised to 500 ℃, the temperature is kept for 8h, washing is carried out by using washing oil, a solid obtained by separation is dried to obtain a composite material of the mesocarbon microbeads uniformly doped with the molecular activating agent, and then the composite material is activated at 800 ℃ to obtain the composite material with the specific surface area of about 1300m2A porous carbon material per gram, the specific capacitance of the porous carbon material being 100F/g.
Comparative example 2
Firstly, adding 300g of KOH powder and 300g of NaOH powder into 1kg of petroleum asphalt, heating to 250 ℃, stirring at a high speed for 1.5h, then heating to 500 ℃, keeping the temperature for 8h, washing by using wash oil, separating to obtain a solid, drying to obtain a composite material of the mesocarbon microbeads uniformly doped with the molecular activator, and then activating at 800 ℃ to obtain the composite material with the specific surface area of about 1250m2Porous carbon material per gram, porous carbonThe specific capacitance of the material was 104F/g.
Comparative example 3
Firstly, 100g of NaOH powder is added into 1kg of petroleum asphalt, the temperature is raised to 250 ℃, the high-speed stirring is carried out for 1.5h, then the temperature is raised to 500 ℃, the temperature is kept for 8h, washing is carried out by using washing oil, the solid obtained by separation is dried to obtain the composite material of the mesocarbon microbeads uniformly doped with the molecular activator, and the composite material is activated at 800 ℃ to obtain the composite material with the specific surface area of about 900m2A porous carbon material per gram, the specific capacitance level of the porous carbon material is 86F/g.
Comparative example 4
The porous carbon material is prepared by adopting a traditional direct activation method, namely, 1kg of petroleum asphalt is heated to 500 ℃ and is kept at the constant temperature for 8 hours, washing is carried out by using washing oil, a solid is obtained by separation and is dried to obtain mesocarbon microbeads, the mesocarbon microbeads are stirred and mixed with 600g of KOH powder for 1.5 hours, and then activation treatment is carried out at 800 ℃ to obtain the porous carbon material with the specific surface area of about 1500m2The specific capacitance of the porous carbon material is 120F/g, and an SEM photograph of the porous carbon material is shown in FIG. 5.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the invention, so that any modifications, equivalents, improvements and the like, which are within the spirit and principle of the present invention, should be included in the scope of the present invention.

Claims (6)

1. A preparation method of a high-capacitance porous carbon material is characterized by comprising the following steps: the method comprises the following steps:
s1: adding activator powder into the mesocarbon microbead liquid raw material, wherein the addition amount of the activator powder accounts for 20-50% (w/w) of the total mass of the mesocarbon microbead liquid raw material, melting the activator at the temperature of 250-350 ℃, and uniformly mixing the melted activator with the mesocarbon microbead liquid raw material to obtain a mixed material;
s2: continuously heating the mixed material to 450-550 ℃, and keeping the temperature for 4-16h to generate the mesocarbon microbead composite material uniformly doped with the molecular activator;
s3: and (4) washing the composite material obtained in the step (S2), separating out a solid, drying, and activating the dried solid at 800-1000 ℃ to obtain the high-capacitance porous carbon material.
2. The method for producing a high-capacitance porous carbon material according to claim 1, characterized in that: the mesocarbon microbead liquid raw material is one or a mixture of more of coal pitch, coal tar, petroleum pitch, heavy oil and ethylene tar.
3. The method for producing a high-capacitance porous carbon material according to claim 1, characterized in that: the activator powder is NaOH powder, KOH powder, Na2CO3Powder, K2CO3Powder, NaHCO3One or a mixture of several of the powders.
4. The method for producing a high-capacitance porous carbon material according to claim 1, characterized in that: the activator powder is NaOH powder and/or KOH powder.
5. A high-capacitance porous carbon material produced by the method according to any one of claims 1 to 4, characterized in that: the specific surface area of the high-capacitance porous carbon material is 1400 m2/g-2000 m2The specific capacitance is 117F/g-152F/g.
6. Use of the high capacitance porous carbon material of claim 5 in the preparation of supercapacitor electrode materials.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117524746A (en) * 2024-01-04 2024-02-06 西安科技大学 Heavy residual oil-based capacitor carbon microsphere and preparation method and application thereof
WO2024040803A1 (en) * 2022-08-22 2024-02-29 中国石油天然气股份有限公司 Porous carbon material, and preparation method therefor and use thereof

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CN105236404A (en) * 2015-08-20 2016-01-13 深圳市贝特瑞新能源材料股份有限公司 Petroleum coke based activated carbon for electrode material of supercapacitor, preparation method therefor and use thereof
CN107720747A (en) * 2017-10-31 2018-02-23 中国科学院山西煤炭化学研究所 A kind of preparation method rich in mesopore asphalt-base globular active carbon
CN108163855A (en) * 2018-03-26 2018-06-15 北京合众汇能科技有限公司 A kind of method for preparing ultracapacitor activated carbon
CN108584952A (en) * 2018-08-01 2018-09-28 国家能源投资集团有限责任公司 Spherical porous charcoal and preparation method thereof
CN110589824A (en) * 2019-09-03 2019-12-20 中国神华煤制油化工有限公司 Spherical activated carbon and preparation method thereof
CN110697705A (en) * 2019-10-18 2020-01-17 中国铝业股份有限公司 Rapid preparation method of asphalt-based activated carbon with hierarchical pore structure

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN105236404A (en) * 2015-08-20 2016-01-13 深圳市贝特瑞新能源材料股份有限公司 Petroleum coke based activated carbon for electrode material of supercapacitor, preparation method therefor and use thereof
CN107720747A (en) * 2017-10-31 2018-02-23 中国科学院山西煤炭化学研究所 A kind of preparation method rich in mesopore asphalt-base globular active carbon
CN108163855A (en) * 2018-03-26 2018-06-15 北京合众汇能科技有限公司 A kind of method for preparing ultracapacitor activated carbon
CN108584952A (en) * 2018-08-01 2018-09-28 国家能源投资集团有限责任公司 Spherical porous charcoal and preparation method thereof
CN110589824A (en) * 2019-09-03 2019-12-20 中国神华煤制油化工有限公司 Spherical activated carbon and preparation method thereof
CN110697705A (en) * 2019-10-18 2020-01-17 中国铝业股份有限公司 Rapid preparation method of asphalt-based activated carbon with hierarchical pore structure

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024040803A1 (en) * 2022-08-22 2024-02-29 中国石油天然气股份有限公司 Porous carbon material, and preparation method therefor and use thereof
CN117524746A (en) * 2024-01-04 2024-02-06 西安科技大学 Heavy residual oil-based capacitor carbon microsphere and preparation method and application thereof
CN117524746B (en) * 2024-01-04 2024-04-05 西安科技大学 Heavy residual oil-based capacitor carbon microsphere and preparation method and application thereof

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