CN114956041B - Preparation method of nitrogen-doped porous carbon sphere with multistage pore structure - Google Patents
Preparation method of nitrogen-doped porous carbon sphere with multistage pore structure Download PDFInfo
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- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 36
- 229910052799 carbon Inorganic materials 0.000 title claims abstract description 23
- 238000002360 preparation method Methods 0.000 title claims abstract description 8
- 239000011148 porous material Substances 0.000 title claims description 13
- 239000013154 zeolitic imidazolate framework-8 Substances 0.000 claims abstract description 38
- MFLKDEMTKSVIBK-UHFFFAOYSA-N zinc;2-methylimidazol-3-ide Chemical compound [Zn+2].CC1=NC=C[N-]1.CC1=NC=C[N-]1 MFLKDEMTKSVIBK-UHFFFAOYSA-N 0.000 claims abstract description 38
- 238000000034 method Methods 0.000 claims abstract description 25
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000007921 spray Substances 0.000 claims abstract description 14
- 239000000843 powder Substances 0.000 claims abstract description 13
- 239000006185 dispersion Substances 0.000 claims abstract description 7
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 claims description 27
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 26
- 238000001694 spray drying Methods 0.000 claims description 18
- 229910052757 nitrogen Inorganic materials 0.000 claims description 13
- 239000002245 particle Substances 0.000 claims description 6
- LXBGSDVWAMZHDD-UHFFFAOYSA-N 2-methyl-1h-imidazole Chemical compound CC1=NC=CN1 LXBGSDVWAMZHDD-UHFFFAOYSA-N 0.000 claims description 4
- 238000010438 heat treatment Methods 0.000 claims description 4
- 238000003756 stirring Methods 0.000 claims description 4
- SLCITEBLLYNBTQ-UHFFFAOYSA-N CO.CC=1NC=CN1 Chemical compound CO.CC=1NC=CN1 SLCITEBLLYNBTQ-UHFFFAOYSA-N 0.000 claims description 3
- 238000006243 chemical reaction Methods 0.000 claims description 3
- 239000011261 inert gas Substances 0.000 claims description 2
- 238000010521 absorption reaction Methods 0.000 abstract description 31
- 238000002156 mixing Methods 0.000 abstract description 14
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 abstract description 12
- 229910052786 argon Inorganic materials 0.000 abstract description 6
- 239000002149 hierarchical pore Substances 0.000 abstract description 6
- 239000011159 matrix material Substances 0.000 abstract description 6
- 239000012188 paraffin wax Substances 0.000 abstract description 6
- 239000011248 coating agent Substances 0.000 abstract description 3
- 238000000576 coating method Methods 0.000 abstract description 3
- 239000007789 gas Substances 0.000 abstract 1
- 238000001338 self-assembly Methods 0.000 abstract 1
- 239000004005 microsphere Substances 0.000 description 27
- 238000000197 pyrolysis Methods 0.000 description 19
- 239000000463 material Substances 0.000 description 17
- 230000000052 comparative effect Effects 0.000 description 8
- 102000020897 Formins Human genes 0.000 description 6
- 108091022623 Formins Proteins 0.000 description 6
- 239000002131 composite material Substances 0.000 description 5
- 229910002804 graphite Inorganic materials 0.000 description 5
- 239000010439 graphite Substances 0.000 description 5
- 239000012621 metal-organic framework Substances 0.000 description 5
- 238000011056 performance test Methods 0.000 description 5
- 238000001878 scanning electron micrograph Methods 0.000 description 5
- 239000002253 acid Substances 0.000 description 4
- 229910021393 carbon nanotube Inorganic materials 0.000 description 4
- 239000002041 carbon nanotube Substances 0.000 description 4
- 239000006249 magnetic particle Substances 0.000 description 4
- 238000002336 sorption--desorption measurement Methods 0.000 description 4
- 239000011358 absorbing material Substances 0.000 description 3
- 239000003513 alkali Substances 0.000 description 3
- 230000005670 electromagnetic radiation Effects 0.000 description 3
- 229910021389 graphene Inorganic materials 0.000 description 3
- 238000005979 thermal decomposition reaction Methods 0.000 description 3
- 238000003917 TEM image Methods 0.000 description 2
- 239000013078 crystal Substances 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- 229910021392 nanocarbon Inorganic materials 0.000 description 2
- 239000002159 nanocrystal Substances 0.000 description 2
- 238000001179 sorption measurement Methods 0.000 description 2
- 229910003321 CoFe Inorganic materials 0.000 description 1
- 239000012922 MOF pore Substances 0.000 description 1
- 208000012902 Nervous system disease Diseases 0.000 description 1
- 239000002250 absorbent Substances 0.000 description 1
- 230000002745 absorbent Effects 0.000 description 1
- 239000006096 absorbing agent Substances 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 239000002585 base Substances 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 210000003169 central nervous system Anatomy 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000011247 coating layer Substances 0.000 description 1
- 238000013329 compounding Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 230000004064 dysfunction Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000011065 in-situ storage Methods 0.000 description 1
- 238000011068 loading method Methods 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 239000002243 precursor Substances 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
- 238000000935 solvent evaporation Methods 0.000 description 1
- 229910000859 α-Fe Inorganic materials 0.000 description 1
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- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B32/00—Carbon; Compounds thereof
- C01B32/05—Preparation or purification of carbon not covered by groups C01B32/15, C01B32/20, C01B32/25, C01B32/30
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- C—CHEMISTRY; METALLURGY
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- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
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- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
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Abstract
The invention discloses a preparation method of a nitrogen-doped porous carbon sphere with a hierarchical pore structure. According to the method, firstly, an ethanol dispersion solution of a ZIF-8 nanocube is introduced into a spray dryer for self-assembly, and then, the collected dry white powder is pyrolyzed in a tube furnace under the protection of argon gas to obtain the nitrogen-doped porous carbon spheres. When the mixing proportion of the nitrogen-doped porous carbon spheres and the paraffin matrix is 20%, the nitrogen-doped porous carbon spheres can show excellent microwave absorption performance when the thickness of a coating is 1.9mm, the minimum reflection loss reaches-50.5 dB, the effective absorption bandwidth exceeds 5.1GHz, and the nitrogen-doped porous carbon spheres have good application prospects in microwave absorption application.
Description
Technical Field
The invention belongs to the field of preparation of microwave absorbing materials, and relates to a preparation method of a nitrogen-doped porous carbon sphere with a multistage pore structure.
Background
Electromagnetic radiation and interference generated during the operation of electronic and electrical equipment can affect the life and production of people. Prolonged exposure of humans to electromagnetic radiation can lead to central nervous system dysfunction and nervous system disorders. The large amount of energy output by high frequency devices can cause serious interference to other surrounding electronic devices, resulting in degradation and even failure of device and system performance. Accordingly, research into design and development of wave-absorbing materials for eliminating electromagnetic interference and electromagnetic radiation in the human living environment is increasing.
Generally, the wave absorbing material needs to meet the requirements of thin thickness, wide absorption bandwidth, light weight and strong absorption capacity. The traditional ferrite absorbent can meet the requirements of high absorption efficiency, thin coating and wide absorption bandwidth, but has the defects of large specific gravity and poor temperature stability, and is difficult to meet the requirements of different application environments. The porous carbon structure based on the metal organic framework has light weight and acid and alkali resistance, and can effectively solve the problems. Thus, a large number of documents have so far achieved their excellent wave absorbing properties by MOF-based composite absorbers. Most MOF-based composite materials still require composite magnetic particles, similar to Fe, co 3 O 4 、Fe 2 O 3 And the like, the magnetic particles may fail in a strong acid environment, and materials such as composite carbon nanotubes and graphene have the disadvantage of high price. Document 1 (Wang Y, wang H, ye J, et al magnetic CoFe alloy@C nanocomposis)tes derived from ZnCo-MOF for electromagnetic wave absorption.2019.) by in-situ growth, carbon nanotubes and graphene are compounded on ZnCo-MOF, and then Fe is loaded by mechanical mixing 3+ However, the high price of carbon nanotubes and the easy failure of mechanically mixed Fe loading on the surface in acid-base environments limit their further development and application.
Disclosure of Invention
The invention aims to provide a preparation method of a nitrogen-doped porous carbon sphere with a multi-level pore structure. According to the method, a spray drying-pyrolysis method is adopted, a porous MOF ZIF-8 nano material is used as a template to prepare the nitrogen-doped nano carbon sphere (NC microsphere) with a multi-level pore structure, and the nitrogen-doped nano carbon sphere has excellent microwave absorption performance and good acid and alkali resistance under the condition of not compounding magnetic particles, graphene, carbon nano tubes and other materials.
The technical solution for realizing the purpose of the invention is as follows:
the preparation method of the nitrogen-doped porous carbon sphere with the multistage pore structure comprises the following steps:
step 1, spray-drying an ethanol dispersion solution of a ZIF-8 nanocube, and collecting dry white powder, wherein the spray-drying conditions are as follows: the input speed of the atomizer is 4.5-6.0 mL min -1 The temperature of the spray head is set to be 110-120 ℃, and the nitrogen circulation rate is 667L min -1 ；
And 2, heating the dried white powder to 1000+/-50 ℃ in a tube furnace under the protection of inert gas, and pyrolyzing for 2+/-0.5 h to obtain the nitrogen-doped porous carbon spheres with the multi-stage pore structure.
In the step 1, the ZIF-8 nanocubes are prepared by adopting the existing method, and specifically comprise the following steps: zn (NO) 3 ) 2 Dropwise adding the methanol solution into 2-methylimidazole (MeIM) methanol solution, stirring for reacting for 3 hours, and centrifuging after the reaction is finished to obtain ZIF-8 nanocubes, wherein Zn (NO 3)2 The concentration of the methanol solution is 0.08 to 1mol L -1 ，Zn(NO 3)2 The concentration ratio of the methanol solution to the 2-methylimidazole methanol solution is 1:6-8.
Preferably, in the step 1, the particle size of the ZIF-8 nanocubes is 40-60 nm.
Preferably, in step 1, the concentration of ZIF-8 nanocubes in the ethanol dispersion solution is 2-10 g/L.
Preferably, in the step 2, the temperature rising rate is 2-10 ℃ for min -1 。
Compared with the prior art, the invention has the advantages that:
(1) According to the invention, a spray drying method is adopted, the microscopic physical assembly of the ZIF-8 nanocubes is realized through a solvent evaporation process, and then the self-assembled ZIF-8 nanocubes precursor is pyrolyzed to prepare the nitrogen-doped porous carbon spheres with a multistage pore structure, so that the process is simple and convenient, and the method is suitable for industrial mass production.
(2) The nitrogen-doped porous carbon sphere with the hierarchical pore structure does not contain magnetic particles, realizes excellent microwave absorption performance only by virtue of the hierarchical pore structure, and has the advantages of thin coating thickness, light weight, wide absorption bandwidth and the like. Meanwhile, the material has acid and alkali resistance, and can still maintain excellent absorption performance in extreme environments.
Drawings
FIG. 1 is a schematic diagram of a method for preparing a nitrogen-doped porous carbon sphere having a hierarchical pore structure according to the present invention.
FIG. 2 is an SEM plot (a) of a ZIF-8 nanocube and experimental (upper line) and simulated (bottom line) XRD plots (b) of a ZIF-8 nanocube.
FIGS. 3 (a) and (b) are SEM images of ZIF-8 microspheres prepared by a spray drying method, (c) and (d) are SEM images of nitrogen-doped porous carbon spheres prepared by a spray drying-pyrolysis method, and (e) and (f) are TEM images of nitrogen-doped porous carbon spheres prepared by a spray drying-pyrolysis method.
FIG. 4 is a graph showing the nitrogen adsorption-desorption curves of ZIF-8 microsphere materials prepared by spray drying.
FIG. 5 is a nitrogen adsorption-desorption curve for NC@1000 microspheres.
FIG. 6 is a graph showing the microwave absorption performance of NC@1000 microspheres of example 1 at a mixing ratio of 20% with graphite under pyrolysis conditions of 1000 ℃.
FIG. 7 is a graph showing the microwave absorption performance of NC@600 microspheres of comparative example 1 at a mixing ratio of 25% with graphite under pyrolysis conditions at 600 ℃.
FIG. 8 is a graph showing the microwave absorption performance of NC@800 microspheres of comparative example 2 at a mixing ratio of 20% with graphite under pyrolysis conditions at 800 ℃.
FIG. 9 is a graph showing the microwave absorption performance of NC@1000 microspheres of comparative example 3 at a mixing ratio of 25% with graphite under pyrolysis conditions at 1000 ℃.
FIG. 10 is a graph showing the microwave absorption performance of NC@1000-1 microspheres of comparative example 4, which were prepared by directly pyrolyzing at 1000℃without spray drying, at a mixing ratio of 20% with graphite.
Detailed Description
The invention will be described in further detail with reference to the drawings and the specific examples.
In the following examples, ZIF-8 nanocubes were prepared by the following steps:
250mL of Zn (NO) 3 ) 2 Methanol solution (0.1 mol L) -1 ) Drop wise to 250mL of 2-methylimidazole methanol solution (0.8 mol L) -1 ) In the process, the reaction is stirred vigorously for 3 hours at room temperature, the mixture is centrifuged (11000 rpm,1 minute), ZIF-8 nanocubes are precipitated, and then the mixture is dispersed in ethanol again by ultrasonic waves, so that an ethanol dispersion solution of ZIF-8 nanocubes with the concentration of 2-10 g/L is formed.
Example 1
Step 1: the ZIF-8 nanocubes ethanol dispersion solution with the concentration of 5g/L is introduced into a small spray dryer for spray drying, and the dried white powder is collected. The atomizer input rate was 5.2mL min -1 The temperature of the spray head is set to 120 ℃, and the nitrogen circulation rate is 667L min -1 。
Step 2: collecting dry white powder, placing in a tube furnace under argon protection, and standing at 10deg.C for min -1 The temperature rise rate of (2) is raised to 1000 ℃ for pyrolysis for 2 hours, and the nitrogen doped porous carbon sphere is obtained and is named NC@1000.
Fig. 2 (a) is an SEM image of a ZIF-8 nanocube prepared using a method of normal temperature stirring, showing that it has a uniform size and morphology, a particle size of 40 to 60nm, and fig. 2 (b) is an XRD image of a ZIF-8 nanocube prepared using a method of normal temperature stirring, showing that it is consistent with the structure previously reported.
Fig. 3 (a) and 3 (b) are SEM images of the ZIF-8 material self-assembled by the spray drying process, showing that the material is spherical, the size is mainly in normal distribution, the particle size range is 800-4000 nm, 200 sphere samples are measured and averaged, and the average particle size of the obtained spheres is 1960nm. Fig. 3 (c) and fig. 3 (d) are SEM images of the nitrogen-doped porous carbon spheres prepared by high-temperature pyrolysis at 1000 ℃, and fig. 3 (e) and fig. 3 (f) are corresponding TEM images, which show that the material still maintains a spherical morphology after high-temperature pyrolysis, and has an interconnected porous frame structure. The size of the material still presents normal distribution, and compared with the size of the material before thermal decomposition, the size of the material is reduced, the size range is 600-1500 nm, 200 ball samples are measured and averaged, and the average particle size of the obtained balls is 985nm.
N at 77K temperature 2 The adsorption-desorption curves of (2) characterize the pore channel structures of the material before and after thermal decomposition, and the result is shown in figure 4, and the N of the ZIF-8 microsphere prepared by a spray drying method 2 The adsorption curve of (a) is a typical I-type curve, the structure is mainly shown to be a microporous structure, the hysteresis loop in the isothermal curve shows that a certain proportion of mesopores exist in the ZIF-8 nano crystal material assembled by spray drying, and the BET specific surface area is 698.72m after calculation 2 g -1 Langmuir specific surface area of 1066.11m 2 g -1 The size of the micropores is about 0.67nm, and the size of the mesopores is about 40-70 nm. As shown in FIG. 5, N of NC@1000 microspheres obtained by thermal decomposition of ZIF-8 composite material prepared by spray drying method 2 The adsorption curve of (a) is an I-type curve, the structure is proved to have a microporous structure, the hysteresis loop in the isothermal curve is proved to have a certain proportion of mesopores in the material, and the BET specific surface area is 707.53m after calculation 2 g -1 Langmuir specific surface area of 1074.73m 2 g -1 The size of the micropores is about 0.84nm, and the size of the mesopores is about 50-70 nm. As can be seen from the adsorption-desorption curves of the materials before and after the pyrolysis process, after the material passes through the pyrolysis, the pore structure and the specific surface area of the material are not greatly changed, and micropores in the material are mainly from ZIF-8 nanometersThe crystal and the mesoporous are mainly generated in the process of physically assembling ZIF-8 nanocrystals into ZIF-8 microspheres in a spray drying process.
The NC@1000 microsphere is subjected to microwave absorption performance test according to the mixing ratio of the NC@1000 microsphere to the paraffin matrix of 20%, and excellent microwave absorption performance is shown under the line. The coating layer showed excellent microwave absorption performance at a thickness of 1.9mm, and minimum reflection loss (RL min ) Reaching-50.5 dB, the effective absorption bandwidth (EAB, RL) exceeds 5.1GHz, as shown in fig. 6.
Comparative example 1
Step 1: introducing an ethanol solution of ZIF-8 nanocubes with the concentration of 5g/L into a small spray dryer for spray drying, and collecting dry white powder. The atomizer input rate was 5.2mL min -1 The temperature of the spray head is set to 120 ℃, and the nitrogen circulation rate is 667L min -1 。
Step 2: collecting dry white powder, placing in a tube furnace under argon protection, and standing at 10deg.C for min -1 The temperature rise rate of (2) is raised to 600 ℃ for pyrolysis for 2 hours, and the nitrogen doped porous carbon sphere is obtained and is named NC@600.
The NC@600 microsphere and paraffin matrix were subjected to a microwave absorption performance test according to the mixing ratio of 25%, and the microwave absorption performance chart of the NC@600 microsphere is shown in FIG. 7.
Comparative example 2
Step 1: introducing an ethanol solution of ZIF-8 nanocubes with the concentration of 5g/L into a small spray dryer for spray drying, and collecting dry white powder. The atomizer input rate was 5.2mL min -1 The temperature of the spray head is set to 120 ℃, and the nitrogen circulation rate is 667L min -1 。
Step 2: collecting dry white powder, placing in a tube furnace under argon protection, and standing at 10deg.C for min -1 The temperature rise rate of (2) is increased to 800 ℃ for pyrolysis for 2 hours, and the nitrogen doped porous carbon sphere is obtained and is named NC@800.
The NC@800 microsphere and paraffin matrix are mixed according to the mixing ratio of 20%, and the NC@800 microsphere is subjected to microwave absorption performance test, and the microwave absorption performance chart is shown in figure 8.
As can be seen from fig. 7 and 8, when the pyrolysis temperature is not high enough, since the assembled ZIF-8 microsphere is not completely carbonized, the pore structure is not completely opened, and a sufficient hierarchical pore structure cannot be formed, and thus the microwave absorption performance is not excellent. Minimum Reflection Loss (RL) of NC@600 microspheres prepared by pyrolysis at 600 DEG C min ) No more than-10 dB, no wave absorbing performance, and minimal Reflection Loss (RL) of NC@800 microsphere prepared by pyrolysis at 800 DEG C min ) Not more than-20 dB, and poor wave absorbing performance.
Comparative example 3
Step 1: introducing an ethanol solution of ZIF-8 nanocubes with the concentration of 5g/L into a small spray dryer for spray drying, and collecting dry white powder. The atomizer input rate was 5.2mL min -1 The temperature of the spray head is set to 120 ℃, and the nitrogen circulation rate is 667L min -1 。
Step 2: collecting dry white powder, placing in a tube furnace under argon protection, and standing at 10deg.C for min -1 The temperature rise rate of (2) is raised to 1000 ℃ for pyrolysis for 2 hours, and the nitrogen doped porous carbon sphere is obtained and is named NC@1000.
The NC@1000 microsphere and paraffin matrix were subjected to a microwave absorption performance test according to the mixing ratio of 25%, and the microwave absorption performance chart of the NC@1000 microsphere is shown in FIG. 9. As can be seen from the graph, at this mixing ratio, the NC@1000 microsphere has a minimum reflection loss (RL min ) Reaching-30 dB, the wave absorbing performance is not as good as that of NC@1000 microsphere with the mixing proportion of 20 percent.
Comparative example 4
Step 1: the ZIF-8 nanocube crystals were precipitated by centrifugation and dried overnight in an oven at 60 ℃.
Step 2: drying ZIF-8 nanocubes in a tube furnace under argon protection at 10deg.C for min -1 Heating to 1000 ℃ for pyrolysis for 2 hours to obtain the NC@1000-1 doped with nitrogen.
The NC@1000-1 microsphere is subjected to microwave absorption performance test according to the mixing ratio of the NC@1000-1 microsphere and the paraffin matrix of 20%, and the microwave absorption performance chart is shown in figure 10. As can be seen from the figure, ZIF-8 obtained without spray drying is free fromThrough microscopic physical assembly, it does not contain a hierarchical pore structure, and therefore its microwave absorption performance is poor, and the minimum Reflection Loss (RL) min ) Less than-20 dB.
Claims (5)
1. The preparation method of the nitrogen-doped porous carbon sphere with the multistage pore structure is characterized by comprising the following steps of:
step 1, spray-drying an ethanol dispersion solution of a ZIF-8 nanocube, and collecting dry white powder, wherein the spray-drying conditions are as follows: the input speed of the atomizer is 4.5-6.0 mL min -1 The temperature of the spray head is set to be 110-120 ℃, and the nitrogen circulation rate is 667L min -1 ；
And 2, heating the dried white powder to 1000+/-50 ℃ in a tube furnace under the protection of inert gas, and pyrolyzing for 2+/-0.5 h to obtain the nitrogen-doped porous carbon spheres with the multi-stage pore structure.
2. The method of claim 1, wherein in step 1, the ZIF-8 nanocubes are prepared by: zn (NO) 3 ) 2 Dropwise adding the methanol solution into 2-methylimidazole (MeIM) methanol solution, stirring for reacting for 3 hours, and centrifuging after the reaction is finished to obtain ZIF-8 nanocubes, wherein Zn (NO 3)2 The concentration of the methanol solution is 0.08 to 1mol L -1 ，Zn(NO 3)2 The concentration ratio of the methanol solution to the 2-methylimidazole methanol solution is 1:6-8.
3. The method according to claim 1, wherein in step 1, the particle size of the ZIF-8 nanocubes is 40-60 nm.
4. The method according to claim 1, wherein in step 1, the concentration of the ZIF-8 nanocubes in the ethanol dispersion solution is 2 to 10g/L.
5. The process according to claim 1, wherein in step 2, the heating rate is 2 to the upper10℃min -1 。
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| CN108671952A (en) * | 2018-05-09 | 2018-10-19 | 安徽师范大学 | Fe-N codope porous carbon ball composite material and preparation methods and application |
| CN112062229A (en) * | 2020-08-12 | 2020-12-11 | 浙江工业大学 | Bi/MOF-derived porous carbon sphere composite material and preparation method and application thereof |
| CN114464783A (en) * | 2021-12-30 | 2022-05-10 | 广东省科学院化工研究所 | Composite cathode material and preparation method and application thereof |
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| CN108671952A (en) * | 2018-05-09 | 2018-10-19 | 安徽师范大学 | Fe-N codope porous carbon ball composite material and preparation methods and application |
| CN112062229A (en) * | 2020-08-12 | 2020-12-11 | 浙江工业大学 | Bi/MOF-derived porous carbon sphere composite material and preparation method and application thereof |
| CN114464783A (en) * | 2021-12-30 | 2022-05-10 | 广东省科学院化工研究所 | Composite cathode material and preparation method and application thereof |
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