CN110416548B - Preparation method and application of two-dimensional structure of nitrogen-doped porous carbon - Google Patents

Preparation method and application of two-dimensional structure of nitrogen-doped porous carbon Download PDF

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CN110416548B
CN110416548B CN201910752196.2A CN201910752196A CN110416548B CN 110416548 B CN110416548 B CN 110416548B CN 201910752196 A CN201910752196 A CN 201910752196A CN 110416548 B CN110416548 B CN 110416548B
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nitrogen
porous carbon
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doped porous
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CN110416548A (en
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余东波
宋清镜
邵齐
崔接武
秦永强
吴玉程
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Hefei University of Technology
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y40/00—Manufacture or treatment of nanostructures
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M10/00—Secondary cells; Manufacture thereof
    • H01M10/05—Accumulators with non-aqueous electrolyte
    • H01M10/054—Accumulators with insertion or intercalation of metals other than lithium, e.g. with magnesium or aluminium
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/36—Selection of substances as active materials, active masses, active liquids
    • H01M4/38—Selection of substances as active materials, active masses, active liquids of elements or alloys
    • H01M4/42—Alloys based on zinc
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/624—Electric conductive fillers
    • H01M4/625—Carbon or graphite
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M4/62—Selection of inactive substances as ingredients for active masses, e.g. binders, fillers
    • H01M4/628—Inhibitors, e.g. gassing inhibitors, corrosion inhibitors
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M4/00—Electrodes
    • H01M4/02—Electrodes composed of, or comprising, active material
    • H01M2004/026—Electrodes composed of, or comprising, active material characterised by the polarity
    • H01M2004/027—Negative electrodes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/10—Energy storage using batteries

Abstract

The invention discloses a preparation method of a two-dimensional structure of nitrogen-doped porous carbon, which comprises the following steps: dissolving 2-methylimidazole powder in methanol to form a solution A, and stirring in a water bath kettle; dissolving Zn-HMT powder in methanol to form a solution B; slowly adding the solution B into the solution A, placing the solution B into a water bath kettle, stirring, centrifugally separating a product, washing the product with ethanol, and placing the product into an oven to be dried to obtain a ZIF-8 two-dimensional nanosheet structure; and annealing the ZIF-8 two-dimensional nanosheet structure powder under the protection of argon, and then pickling with nitric acid to obtain a product. The two-dimensional structure of the nitrogen-doped porous carbon prepared by the method can be widely applied to the fields of electrochemical energy storage, separation and purification, drug sustained release and the like.

Description

Preparation method and application of two-dimensional structure of nitrogen-doped porous carbon
Technical Field
The invention relates to the technical field of micro-nano composite material synthesis, in particular to a preparation method and application of a two-dimensional structure of nitrogen-doped porous carbon, which is obtained by taking Metal Organic Frameworks (MOFs) as precursors and combining argon annealing treatment.
Background
Metal Organic Frameworks (MOFs) are periodic porous crystalline coordination polymer materials formed by self-assembly of transition metal ions and different organic ligands containing oxygen, nitrogen, etc. through covalent bonds or ion-covalent bond coordination, and are also called Porous Coordination Polymers (PCPs). The MOFs can complex organic ligands through different metal ions, and design and manufacture metal organic frameworks with different pore structures and different physical and chemical characteristics. MOFs have the following characteristics: porosity, high specific surface area, unsaturated metal active sites, designable pore channel size, functionalizable pore channel surface and the like. The catalyst has excellent performance in the fields of catalysis, energy storage and conversion, gas adsorption and separation and the like. As a multifunctional material, the material for synthesizing the MOFs can enable the raw material with lower cost to have low frame density and high thermal stability, and the advantages enable the MOFs to become a candidate material of an energy material. Therefore, the two-dimensional structure of the nitrogen-doped porous carbon prepared by the invention combines the large specific surface area of the porous carbon, provides more active sites for storing potassium ions, and plays an effective buffer role in the volume expansion of the material in the process of embedding and removing the potassium ions; nitrogen doping brings a large number of crystal defects and contributes to higher specific capacity. Further expands the application field of MOFs materials, fully exerts the structural characteristics of large specific surface, high porosity and modifiability of the MOFs materials and has great practical utilization value.
Disclosure of Invention
The invention aims to: provides a preparation method of a two-dimensional structure of nitrogen-doped porous carbon, and aims to develop an electrode material applied to a high-performance potassium ion battery. The material has simple preparation method, low cost and wide application prospect.
In order to achieve the above purpose, the invention provides the following technical scheme:
a preparation method of a two-dimensional structure of nitrogen-doped porous carbon comprises the following steps:
(1) dissolving 2-methylimidazole powder in methanol to form a solution A, and stirring in a water bath kettle;
(2) dissolving Zn-HMT powder in methanol to form a solution B;
(3) slowly adding the solution B into the solution A, placing the solution B into a water bath kettle, stirring, centrifugally separating a product, washing the product with ethanol, and placing the product into an oven to be dried to obtain a ZIF-8 two-dimensional structure;
(4) annealing the ZIF-8 two-dimensional structure powder under the protection of argon to obtain a two-dimensional structure (possibly containing zinc) of the nitrogen-doped porous carbon;
(5) and (3) placing the two-dimensional material (possibly containing zinc) of the nitrogen-doped porous carbon in a nitric acid solution, stirring in a water bath for reaction, then centrifugally separating the product, washing with ethanol, and placing in a drying oven for drying to obtain the pure two-dimensional structure of the nitrogen-doped porous carbon.
Preferably, in the step (1), the concentration of 2-methylimidazole in the solution A is 0.974mol L-1The temperature in the water bath is 30 ℃;
preferably, in step (2), the concentration of solution B is 1.828g L-1。
Preferably, in the step (3), the temperature in the water bath is 30 ℃, and the stirring time is 15 min; the temperature of the oven is 75-85 ℃.
Preferably, in the step (4), the annealing temperature is 900 ℃, and the holding time is 2 hours;
preferably, in step (5), the volume ratio of the concentrated nitric acid to the water in the nitric acid solution is 1: 2.
Preferably, in the step (5), the water bath temperature is 75-85 ℃, and the water bath time is 23-25 h.
Preferably, in step (5), the temperature of the oven is 75-85 ℃.
Further, the prepared two-dimensional structure of the nitrogen-doped porous carbon can be used as a negative electrode material of a high-performance potassium ion battery.
Compared with the prior art, the invention has the beneficial technical effects that:
1. the two-dimensional structure of the nitrogen-doped porous carbon prepared by the invention realizes that metal ions and a specific MOF material form a composite structure on the one hand, and then the structure of the porous carbon is obtained through high-temperature calcination treatment, thereby fully exerting the structural characteristics of large specific surface area, high porosity and modifiability of the MOF material. On the other hand, the porous carbon material has high specific surface area, excellent electron transmission rate and good stability, and the nitrogen-doped porous carbon can enhance the conductivity of the porous carbon material, reduce the physical properties such as the valence band and the like, increase the surface wetting capacity of the porous carbon material, improve the chemical properties such as the catalytic activity, the adsorption capacity and the like, and further improve the electrochemical performance of the porous carbon material, so that a new method is provided for preparing the two-dimensional structure of the nitrogen-doped porous carbon;
2. ZIF-8 synthesized by the traditional method is in a solid particle structure, the ZIF-8 with a two-dimensional sheet structure is successfully prepared by the method, and the preparation method is simple, easy to operate, safe, pollution-free and low in cost.
3. The two-dimensional structure of the nitrogen-doped porous carbon prepared by the invention can be applied to the fields of electrochemical energy storage, separation and purification, drug sustained release and the like.
Drawings
FIG. 1 is a FESEM image of Zn-HMT prepared in example 1.
FIG. 2 is a FESEM and TEM image of ZIF-8 two-dimensional nanosheet structure prepared in example 2.
Fig. 3 is FESEM and TEM images of the two-dimensional structure of nitrogen-doped porous carbon prepared in example 2.
FIG. 4 is an XRD pattern of ZIF-8 two-dimensional nanoplate structures prepared in example 2.
Fig. 5 is a graph of the electrochemical performance of the two-dimensional structure of nitrogen-doped porous carbon prepared in example 3.
Detailed Description
For the convenience of understanding of those skilled in the art, the present invention will be described with reference to the accompanying drawings and examples.
EXAMPLE 1 preparation of Zn-HMT powder
(1) Dissolving 4.24g of zinc nitrate hexahydrate in 30ml of ethanol to form a solution A, adding 1.0g of hexamethylenetetramine into 50ml of ethanol, stirring at room temperature until the hexamethylenetetramine is completely dissolved to form a solution B, adding the solution A into the solution B, and continuously stirring at room temperature for reacting for 15 min;
(2) and respectively centrifugally separating the products, washing the products with ethanol, and drying the products in an oven at 80 ℃ to obtain zinc-hexamethylenetetramine powder, namely Zn-HMT powder for short.
FIG. 1 is a FESEM image of Zn-HMT prepared by the present example, and the thickness of the nanosheet is 10-20 nm.
Example 2, preparation of ZIF-8 two-dimensional nanosheet structure and two-dimensional structure of nitrogen-doped porous carbon (1) 4.0g of 2-methylimidazole was dissolved in 50ml of methanol to form solution a, stirred in a 30 ℃ water bath, 0.0366g of Zn-HMT powder was dissolved in 20ml of methanol to form solution B, solution B was poured into solution a, and stirred in a 30 ℃ water bath for reaction for 15 min.
(2) And (3) centrifugally separating the product, washing the product with ethanol, and drying the product in an oven at 80 ℃ to obtain the ZIF-8 two-dimensional structure.
(3) And (2) annealing the ZIF-8 two-dimensional structure with argon at 900 ℃, pickling in a nitric acid solution, stirring for 24 hours at 80 ℃, centrifugally separating the product, washing for 3 times with ethanol, and then drying the product in an oven at 80 ℃ to obtain the two-dimensional structure of the nitrogen-doped porous carbon.
FIG. 2 is FESEM and TEM images of a two-dimensional structure of ZIF-8 prepared in this example. Fig. 3 is FESEM and TEM images of 900 ℃ two-dimensional structures of nitrogen-doped porous carbon prepared in this example. It can be found that the original nanosheets are converted into a large number of particles, forming a two-dimensional structure. FIG. 4 is an XRD pattern of the two-dimensional plate-like ZIF-8 structure prepared in this example, corresponding 2 θ to 7.48 °, 10.52 °, 12.84 °, 14.92 °, 16.60 ° and 18.12 °, respectively, corresponding to standard peak positions reported in the literature, indicating successful conversion of Zn-HMT to ZIF-8 crystals.
Example 3 Performance testing of two-dimensional Structure of Nitrogen-doped porous carbon
(1) Uniformly mixing and dissolving a two-dimensional structure of nitrogen-doped porous carbon, conductive carbon black and PVDF in a mass ratio of 7:1:2 in 1-methyl-2-pyrrolidone (NMP) to prepare slurry, uniformly coating the slurry on a copper foil current collector, and drying the copper foil current collector in a vacuum drying oven at 60 ℃ for 24 hours.
(2) Slicing the dried copper foil current collector to prepare a working electrode, taking glass fiber as a diaphragm and electrolyte as binary electrolyte, assembling the working electrode and the electrolyte into a 2032 button cell in a glove box filled with argon, wherein the test voltage range is 0.01V-3V vs K+/K。
Fig. 5 is a two-dimensional structure potassium electrochemical storage potassium ion performance graph of nitrogen-doped porous carbon prepared in example 3. It can be seen that the potassium electrical properties of the two-dimensional structure of the nitrogen-doped porous carbon are better.
The above examples are typical examples of the present invention, and are not intended to limit the present invention, for example, the reaction concentration, the reaction time, the water bath temperature, the annealing temperature, etc. can be further adjusted. Therefore, it is within the scope of the present invention to modify and modify the process parameters described by those skilled in the art without departing from the spirit of the invention or exceeding the scope defined by the claims.

Claims (6)

1. A preparation method of a two-dimensional structure of nitrogen-doped porous carbon is characterized by comprising the following steps:
(1) dissolving 2-methylimidazole powder in methanol to form a solution A, and stirring in a water bath kettle;
(2) dissolving Zn-HMT powder in methanol to form a solution B;
(3) slowly adding the solution B into the solution A, placing the solution B into a water bath kettle, stirring, centrifugally separating a product, washing the product with ethanol, and placing the product into an oven to be dried to obtain a ZIF-8 two-dimensional nanosheet structure;
(4) annealing the ZIF-8 two-dimensional nanosheet structure powder under the protection of argon to obtain a nitrogen-doped porous carbon two-dimensional nanosheet structure;
(5) placing the two-dimensional nanosheet material of the nitrogen-doped porous carbon into a nitric acid solution, performing stirring reaction in a water bath, performing centrifugal separation on a product, washing the product with ethanol, and drying the product in an oven to obtain a pure two-dimensional nanosheet structure of the nitrogen-doped porous carbon;
wherein in the step (1), the concentration of the 2-methylimidazole in the solution A is 0.974mol L-1The temperature in the water bath is 30 ℃;
in the step (2), the concentration of the solution B is 1.828g L-1；
In the step (3), the temperature in the water bath is 30 ℃, and the stirring time is 15 min; the temperature of the oven is 75-85 ℃.
2. The method for preparing a two-dimensional structure of nitrogen-doped porous carbon according to claim 1, wherein in step (4), the annealing temperature is 900 ℃ and the holding time is 2 hours.
3. The method for preparing a two-dimensional structure of nitrogen-doped porous carbon according to claim 1, wherein in step (5), the volume ratio of concentrated nitric acid to water in the nitric acid solution is 1: 2.
4. The method for preparing a two-dimensional structure of nitrogen-doped porous carbon according to claim 1, wherein in step (5), the water bath temperature is 75-85 ℃ and the water bath time is 23-25 h.
5. The method for preparing a two-dimensional structure of nitrogen-doped porous carbon according to claim 1, wherein in step (5), the temperature of the oven is 75-85 ℃.
6. Use of the two-dimensional structure of nitrogen-doped porous carbon prepared by the method according to any one of claims 1 to 5, for a negative electrode material for high-performance potassium ion batteries.
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CN111326745B (en) * 2020-02-12 2021-07-27 北京化工大学 Two-dimensional zinc monoatomic/carbon nitrogen composite material and preparation method and application thereof
CN111533124A (en) * 2020-05-12 2020-08-14 湖南鑫恒环境科技有限公司 Two-dimensional nitrogen-doped nano porous carbon material and preparation method thereof
CN111916736B (en) * 2020-08-11 2023-03-17 合肥工业大学 Preparation method and application of porous carbon with two-dimensional core-shell structure
CN112138697B (en) * 2020-09-14 2022-12-20 广州大学 Preparation method and application of manganese-nitrogen co-doped carbon nanosheet electrocatalyst
CN112642457B (en) * 2020-12-21 2022-07-08 安徽师范大学 Hollow iron-based metal organic framework material, iron-doped carbon-nitrogen nano material and preparation method
CN114057183B (en) * 2021-11-22 2022-08-26 合肥工业大学 Preparation method of nitrogen-doped dendritic porous carbon nanotube

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