CN114864969A - Cobalt-based multifunctional catalyst imitating branch and leaf structure of Pinus thunbergii and preparation method thereof - Google Patents
Cobalt-based multifunctional catalyst imitating branch and leaf structure of Pinus thunbergii and preparation method thereof Download PDFInfo
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- 239000010941 cobalt Substances 0.000 title claims abstract description 36
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- 239000000243 solution Substances 0.000 claims description 21
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- 239000002041 carbon nanotube Substances 0.000 claims description 12
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- 239000010439 graphite Substances 0.000 claims description 11
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- QGUAJWGNOXCYJF-UHFFFAOYSA-N cobalt dinitrate hexahydrate Chemical compound O.O.O.O.O.O.[Co+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O QGUAJWGNOXCYJF-UHFFFAOYSA-N 0.000 claims description 8
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- YSWBFLWKAIRHEI-UHFFFAOYSA-N 4,5-dimethyl-1h-imidazole Chemical compound CC=1N=CNC=1C YSWBFLWKAIRHEI-UHFFFAOYSA-N 0.000 claims description 6
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Images
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- 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
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/9041—Metals or alloys
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- 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
- H01M4/00—Electrodes
- H01M4/86—Inert electrodes with catalytic activity, e.g. for fuel cells
- H01M4/90—Selection of catalytic material
- H01M4/9075—Catalytic material supported on carriers, e.g. powder carriers
- H01M4/9083—Catalytic material supported on carriers, e.g. powder carriers on carbon or graphite
-
- 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
- Y02E60/30—Hydrogen technology
- Y02E60/50—Fuel cells
Abstract
The invention discloses a cobalt-based multifunctional catalyst with an imitation Pinus nigra branch and leaf structure and a preparation method thereof, belonging to the technical field of catalyst preparation. The catalyst prepared by the method has a self-supporting 3D structure, avoids the reduction of catalytic activity caused by using a binder compared with the traditional powdery catalyst, and is more firmly combined with a substrate, so that the catalyst has better conductivity, higher catalytic activity and better stability; the raw materials used in the invention are non-noble metals, the cost is low, the preparation process is simple, and the production cost is greatly reduced.
Description
Technical Field
The invention belongs to the technical field of catalyst preparation, and particularly relates to a cobalt-based multifunctional catalyst imitating a branch and leaf structure of Pinus thunbergii and a preparation method thereof.
Background
With the development of science and technology, the development of clean energy capable of replacing fossil energy has become a difficult problem and a hot spot to be solved urgently. The proton exchange membrane fuel cell is a key focus of solving the problem of energy environment due to the advantages of energy conservation, high conversion efficiency and nearly zero pollution emission, and has very excellent application potential in the field of new energy. However, the catalyst used in the fuel cell has the problems of insufficient catalytic activity, poor stability, short service life and the like, and the application of the fuel cell is greatly limited.
At present, noble metals such as platinum, palladium and the like are widely used as catalysts in fuel cells, but the scarcity of noble metal resources, catalyst poisoning and high cost severely restrict the development of the noble metals in the field of electrocatalysis. The preparation of non-noble metal catalysts from carbon materials is becoming a research hotspot as replacing noble metal catalysts due to low cost, high catalytic efficiency, excellent stability, environmental friendliness, and the like. However, the carbon material catalyst prepared in general is inevitably mixed with a binder during use, so that the activity is reduced, and the catalytic activity and the catalytic efficiency are also reduced because the carbon material catalyst does not have a micro-space three-dimensional structure and active sites are stacked and covered with each other. Therefore, the development of a self-supporting 3D multifunctional catalyst that is efficient, stable and economical is especially important for fuel cell applications.
Disclosure of Invention
Aiming at the defects in the prior art, the invention aims to provide a multifunctional catalyst which has a microscopic space structure, a large specific surface area, high porosity, non-stacking of catalytic active sites and excellent catalytic performances of oxygen evolution, hydrogen evolution and oxygen reduction and a preparation method thereof; the preparation method provided by the invention is low in cost, and the prepared catalyst is high in catalytic efficiency, excellent in stability and environment-friendly.
The needles and the trunk branches of the black pine have typical hierarchical structures, so that the specific surface area and the space porosity of the black pine are greatly improved; in addition, in space, the multi-layer branches and needle leaf structure ensures that the stacking and covering of the leaves are rarely generated; the bionic cobalt-based multifunctional catalyst prepared by the method has a spatial structure on a microscopic scale, a large specific surface area, high porosity, non-stacking of catalytic active sites and excellent catalytic performances of oxygen precipitation, hydrogen precipitation and oxygen reduction.
The invention is realized by the following technical scheme:
a cobalt-based multifunctional catalyst with a pine branch and leaf imitating structure takes carbon paper as a substrate, a Co-MOF sheet grows on the surface of the carbon paper, carbon nano tubes grow on the surface of the Co-MOF sheet, and cobalt cluster particles are distributed on the tube walls of the carbon nano tubes.
Further, the thickness of the Co-MOF sheet is 30-50 μm, the diameter of the carbon nano-tube is 30-50nm, and the particle size of the cobalt cluster particles is 3-8 nm.
A preparation method of a cobalt-based multifunctional catalyst imitating a branch and leaf structure of Pinus thunbergii comprises the following steps:
a: mixing melamine and ethanol, stirring by using a magnetic stirrer to obtain uniform melamine slurry, transferring the slurry into a graphite boat, and drying in a vacuum drying oven at constant temperature;
b: cutting carbon paper into size of 1cm × 0.8cm, sequentially ultrasonic cleaning with acetone, ethanol, and deionized water for 20min, and oven drying in a vacuum drying oven; performing plasma etching on the dried carbon paper, wherein the working frequency is 12-14MHz, the etching time is 5-15min, and placing the treated carbon paper in a glove box in argon atmosphere for later use;
c: respectively dissolving cobalt nitrate hexahydrate and dimethylimidazole in 25mL of deionized water, and magnetically stirring for 30-60min to obtain solutions a and b; pouring the solution a into the solution b, putting the cleaned carbon paper into the mixed solution, standing for 2-6h at room temperature, so that a cobalt-based metal organic metal framework structure (Co-MOF) grows on the carbon paper substrate, and marking the carbon paper obtained at the moment as Co-MOF/CP;
d: and (3) putting the graphite boat filled with the dried melamine in the step (A) and the Co-MOF/CP prepared in the step (C) into a tube furnace, heating to the temperature of 750-1000 ℃ in the nitrogen atmosphere, preserving the heat for 0.5-2h, and naturally cooling to the room temperature to obtain the cobalt-based multifunctional catalyst with the imitation black pine branch and leaf structure, wherein the heating rate is 1.5-2 ℃/min.
Further, the mass-to-volume ratio of the melamine to the ethanol in the step A is 1 mg: 1 mL.
Further, the drying temperature of the melamine slurry in the step A is 50-80 ℃, and the drying time is 2-4 h.
Further, the molar ratio of the cobalt nitrate hexahydrate to the dimethyl imidazole in the step C is 1: 5-9.
Further, in the step D, the molar ratio of melamine to cobalt nitrate hexahydrate is 1: 0.2-0.4.
Further, in the step D, the graphite boat containing the dried melamine and the Co-MOF/CP are sequentially placed along the direction from the air inlet to the air outlet of the tube furnace.
Compared with the prior art, the invention has the following advantages:
1. based on the engineering bionics thought, the invention imitates the characteristics of the branches and leaves of the black pine that the branches and leaves have spatial three-dimensional structures, high porosity and no stacking and covering among the branches and leaves, takes carbon paper as a substrate, and grows micron-sized Co-MOF sheets on the surface of the carbon paper, and also grows a large number of carbon nano tubes on the surface of the Co-MOF sheets, and rich cobalt cluster particles are distributed on the walls of the carbon nano tubes, thereby having rich catalytic active sites and improving the catalytic efficiency; the bionic cobalt-based multifunctional catalyst prepared by the method has a spatial structure on the microcosmic aspect, is large in specific surface area and high in porosity, catalytic active sites are not stacked mutually, and the catalyst has three excellent catalytic performances of oxygen precipitation, hydrogen precipitation and oxygen reduction;
2. the carbon paper substrate is etched by using the plasma, oxygen functional groups and the like are introduced to the surface of the carbon paper, so that the surface performance of the carbon paper is changed, the hydrophilicity of the carbon paper is obviously improved, the growth of Co-MOF on the surface of the carbon paper is facilitated, the morphology is intact, and the mass growth of carbon nanotubes on the surface of the carbon paper is further promoted;
3. the catalyst prepared by the method has a self-supporting 3D structure, avoids the reduction of catalytic activity caused by using a binder compared with the traditional powdery catalyst, and is more firmly combined with a substrate, so that the catalyst has better conductivity, higher catalytic activity and better stability;
4. the raw materials used in the invention are non-noble metals, the cost is low, the preparation process is simple, the production cost is greatly reduced, and the carbon material is more environment-friendly as the catalyst of the fuel cell.
Drawings
In order to more clearly illustrate the detailed description of the invention or the technical solutions in the prior art, the drawings that are needed in the detailed description of the invention or the prior art will be briefly described below. Throughout the drawings, like elements or portions are generally identified by like reference numerals. In the drawings, elements or portions are not necessarily drawn to scale.
FIG. 1 is a scanning electron micrograph of a biomimetic multifunctional catalyst (reaction temperature 820 ℃) prepared by the method of the present invention in example 1;
FIG. 2 is a transmission electron micrograph of the biomimetic multifunctional catalyst (reaction temperature 820 ℃) prepared by the method of the present invention in example 1;
FIG. 3 is the oxygen evolution catalytic performance of the biomimetic multifunctional catalyst (reaction temperature 820 ℃) prepared by the method of the present invention in example 1, wherein a is a linear scanning voltammogram of the oxygen evolution performance, and b is a corresponding Tafel curve;
FIG. 4 is the hydrogen evolution catalytic performance of the biomimetic multifunctional catalyst (reaction temperature 820 ℃) prepared by the method of the present invention in example 1, wherein a is a linear scanning voltammogram of the hydrogen evolution performance, and b is a corresponding Tafel curve;
FIG. 5 is the oxygen reduction catalytic performance of the biomimetic multifunctional catalyst (reaction temperature 820 ℃) prepared by the method of the present invention in example 1, wherein a is a linear scanning voltammogram of the oxygen reduction performance, and b is a corresponding Tafel curve;
FIG. 6 is a scanning electron microscope image of the biomimetic multifunctional catalyst (reaction temperature 920 ℃) prepared by the method of the present invention in example 2;
FIG. 7 is a transmission electron microscope image of the biomimetic multifunctional catalyst (reaction temperature 920 ℃) prepared by the method of the present invention in example 2;
FIG. 8 is the oxygen evolution catalytic performance of the biomimetic multifunctional catalyst (reaction temperature 920 ℃) prepared by the method of the present invention in example 2, wherein a is a linear scanning voltammogram of the oxygen evolution performance, and b is a corresponding Tafel curve;
FIG. 9 shows the hydrogen evolution catalysis performance of the biomimetic multifunctional catalyst (reaction temperature 920 ℃) prepared by the method of the present invention in example 2, wherein a is a linear scanning voltammogram of the hydrogen evolution performance, and b is a corresponding Tafel curve;
FIG. 10 is the oxygen reduction catalytic performance of the biomimetic multifunctional catalyst (reaction temperature 920 ℃) prepared by the method of the present invention in example 2, wherein a is a linear scanning voltammogram of the oxygen reduction performance, and b is a corresponding Tafel curve.
Detailed Description
To further illustrate the preparation method of the present invention, the present invention will be further described in detail with reference to the accompanying drawings and examples, but the embodiments of the present invention are not limited thereto.
Example 1
The embodiment provides a cobalt-based multifunctional catalyst with an imitation black pine branch and leaf structure, which is obtained by the following method:
step A: mixing 6mL of ethanol and 6g of melamine, stirring uniformly to form 1g/mL of melamine slurry, stirring by using a magnetic stirrer, placing the slurry in a graphite boat after uniformly mixing, and drying for later use; wherein the drying temperature is 50 ℃, and the drying time is 2 h;
and B: cutting carbon paper into size of 1cm × 0.8cm, sequentially ultrasonic cleaning with acetone, ethanol, and deionized water for 20min, and oven drying in a vacuum drying oven; etching the dried carbon paper by adopting plasma, wherein the working frequency is 13MHz, the etching time is 5min, and placing the treated carbon paper in a glove box in argon atmosphere for later use;
and C: respectively dissolving 600mg of cobalt nitrate hexahydrate and 1.4g of dimethyl imidazole in 25mL of deionized water, magnetically stirring for 35min, respectively marking the obtained solutions as a solution a and a solution b, quickly pouring the solution a into the solution b, putting the cleaned carbon paper into the mixed solution, standing for 4h at room temperature, thus growing a cobalt-based metal organic metal framework structure (Co-MOF) on the carbon paper substrate, and marking the carbon paper obtained at the moment as Co-MOF/CP;
step D: c, placing the graphite boat containing the dried melamine and the Co-MOF/CP prepared in the step C into a tube furnace, wherein the graphite boat containing the dried melamine and the Co-MOF/CP are sequentially placed along the direction from the air inlet to the air outlet of the tube furnace; heating to 820 ℃ in a nitrogen atmosphere, preserving heat for 1h, and naturally cooling to room temperature to obtain the cobalt-based multifunctional catalyst with the imitation pine branch and leaf structure, wherein the heating rate is 1.5 ℃/min.
The scanning electron micrograph of the obtained cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii is shown in figure 1, and the transmission electron micrograph thereof is shown in figure 2; as can be seen from figure 1, the micro-morphology structure of the bionic multifunctional catalyst is prepared by distributing a flaky cobalt-based metal organic metal framework structure on a carbon paper substrate and distributing a large number of carbon nanotubes on the surface of the flaky structure, so that a morphology structure similar to branches and leaves of Pinus thunbergii is formed, and the microstructure has a spatial structure on a micro scale. The transmission electron micrograph of fig. 2 demonstrates the presence of the cobalt nanoparticle (111) crystal plane and the graphitic carbon (002) crystal plane; the combination of the figure 1 and the figure 2 shows that the cobalt nanoclusters are positioned on the wall of the carbon nano tube, namely the catalytic active sites are positioned on the wall of the carbon nano tube, and the bionic multifunctional catalyst prepared by the invention has a space structure imitating branches and leaves of Pinus thunbergii on a microcosmic view, so that the catalytic active sites cannot be folded and covered mutually in space, and the catalyst has the advantages of large specific surface area and high porosity.
Through test calculation, the capacitance value of the double electric layers of the bionic multifunctional catalyst prepared by the invention can reach 105mF/cm 2 This indicates that the catalyst possesses a high active area to expose a large number of active sites.
The oxygen evolution, hydrogen evolution and oxygen reduction catalytic performances of the obtained bionic multifunctional catalyst are respectively tested, and the obtained performance curve graphs are respectively shown in figure 3, figure 4 and figure 5.
As shown in a and b of FIG. 3, the prepared biomimetic multifunctional catalyst and commercial RuO were tested by a three-electrode system in a 1mol/L KOH solution saturated with nitrogen at room temperature and at a scan rate of 5mV/s 2 The bionic multifunctional catalyst shows excellent oxygen precipitation catalytic activity, and can reach 10mA/cm only by 270mV overpotential 2 Current density of (2) is superior to that of commercial RuO 2 327mV of (1); making biomimetic multifunctional catalyst and commercial RuO by calculation 2 The Tafel curve of the bionic multifunctional catalyst has the Tafel slope of 74mV/dec and is commercially available RuO 2 The Tafel slope is 80mV/dec, which shows that the bionic multifunctional catalyst prepared by the method is more than commercial RuO 2 Has a faster catalytic rate of oxygen evolution.
As shown in a and b of FIG. 4, the hydrogen evolution catalytic performance of the prepared biomimetic multifunctional catalyst and the commercial Pt/C was tested in an oxygen-saturated 1mol/L KOH solution, and the overpotential of the biomimetic multifunctional catalyst at 110mV reaches 10mA/cm 2 The current density of the bionic multifunctional catalyst is 74mV when the commercial Pt/C is adopted, which indicates that the hydrogen precipitation catalytic performance of the bionic multifunctional catalyst is excellent and is close to the commercial Pt/C; the Tafel slopes of the two catalysts are obtained through calculation, the biomimetic multifunctional catalyst is 79mV/dec, and the commercial Pt/C is 42mV/dec, which shows that the hydrogen evolution catalysis rate of the biomimetic multifunctional catalyst is higher and is close to the commercial Pt/C.
As shown in a and b of FIG. 5, the oxygen reduction catalytic performance was tested in 0.1mol/L KOH solution saturated with oxygen, and the starting potential of the biomimetic multifunctional catalyst was 0.94V, the half-wave potential was 0.80V, which is only 36mV lower than commercial Pt/C (0.836V); through calculation, the Tafel slope of the bionic multifunctional catalyst is 92mV/dec, and the Tafel slope of the commercial Pt/C is 75 mV/dec; the electron transfer number of the bionic multifunctional catalyst can be calculated to be about 3.86 according to the Tafel slope and the K-L equation under different rotating speeds (from 400rpm to 1600rpm), and in conclusion, the bionic multifunctional catalyst prepared by the method has good oxygen reduction catalytic performance, is close to commercial Pt/C, and has high-efficiency oxygen reduction catalytic performance because the catalytic oxygen reduction reaction is a four-electron transfer process.
In general, the cobalt-based multifunctional catalyst with the imitation black pine branch and leaf structure, which is prepared by the method, has three excellent catalytic performances of oxygen evolution, hydrogen evolution and oxygen reduction.
Example 2
The embodiment provides a cobalt-based multifunctional catalyst with an imitation black pine branch and leaf structure, which is obtained by the following method:
step A: mixing 8mL of ethanol and 8g of melamine, stirring uniformly to form 1g/mL of melamine slurry, stirring by using a magnetic stirrer, placing the slurry in a graphite boat after uniformly mixing, and drying for later use; wherein the drying temperature is 80 ℃, and the drying time is 4 h;
and B: cutting carbon paper into size of 1cm × 0.8cm, sequentially ultrasonic cleaning with acetone, ethanol, and deionized water for 20min, and oven drying in a vacuum drying oven; the dried carbon paper is etched by adopting plasma, the working frequency is 12.8MHz, the etching time is 8min, and the treated carbon paper is placed in a glove box in argon atmosphere for standby;
and C: respectively dissolving 800mg of cobalt nitrate hexahydrate and 1.8g of dimethylimidazole in 25mL of deionized water, magnetically stirring for 50min, respectively marking the obtained solutions as a solution a and a solution b, quickly pouring the solution a into the solution b, putting the cleaned carbon paper into the mixed solution, and standing for 5h at room temperature, so that a cobalt-based metal organic metal framework structure (Co-MOF) grows on the carbon paper substrate, and marking the obtained carbon paper as Co-MOF/CP;
step D: and (3) putting the graphite boat filled with the dried melamine and the Co-MOF/CP prepared in the step (A) into a tube furnace, heating to 920 ℃ in a nitrogen atmosphere, preserving heat for 1.5h, and naturally cooling to room temperature to obtain the cobalt-based multifunctional catalyst with the imitation black pine branch and leaf structure, wherein the heating rate is 1.8 ℃/min.
The scanning electron micrograph of the obtained bionic multifunctional catalyst is shown in figure 6, and the transmission electron micrograph thereof is shown in figure 7. As can be seen from fig. 5 and 6, the prepared biomimetic multifunctional catalyst has a micro-morphology structure imitating a branch and leaf structure of the Pinus thunbergii, catalytic active sites are not folded and covered with each other, and the catalyst has a high specific surface area.
The oxygen evolution, hydrogen evolution and oxygen reduction catalytic performances of the obtained bionic multifunctional catalyst are respectively tested, and the obtained performance curve graphs are respectively shown as figure 8, figure 9 and figure 10.
As shown in a and b of FIG. 8, the oxygen precipitation catalytic performance of the prepared bionic multifunctional catalyst is excellent, and the performance is similar to that of commercial RuO 2 The catalytic performance is similar, and 10mA/cm can be generated at 302mV overpotential 2 Current density of (d); the Tafel slope is 102 mV/dec; through test calculation, the capacitance value of the double electric layers of the prepared bionic multifunctional catalyst can reach 82mF/cm 2 It is shown that the catalyst has a high active area to expose more active sites.
As shown in a and b of FIG. 9, the biomimetic multifunctional catalyst shows good hydrogen evolution catalysis performance, which reaches 10mA/cm 2 The overpotential of the current density is 142 mV; the Tafel slope is 92mV/dec, which shows that the hydrogen evolution catalytic performance of the catalyst is good and is close to commercial Pt/C.
As shown in a and b of fig. 10, the oxygen reduction catalytic performance of the prepared biomimetic multifunctional catalyst is good, the initial potential is 0.92V, and the half-wave potential is 0.79V; the Tafel slope is 102 mV/dec.
In conclusion, the bionic multifunctional catalyst prepared by the preparation method has three excellent catalytic performances of oxygen evolution, hydrogen evolution and oxygen reduction.
The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, however, the present invention is not limited to the specific details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications are within the protective scope of the present invention.
It should be noted that the various technical features described in the above embodiments can be combined in any suitable manner without contradiction, and the invention is not described in any way for the possible combinations in order to avoid unnecessary repetition.
In addition, any combination of the various embodiments of the present invention is also possible, and the same should be considered as the disclosure of the present invention as long as it does not depart from the spirit of the present invention.
Claims (8)
1. A cobalt-based multifunctional catalyst with a pine branch and leaf imitating structure is characterized in that carbon paper is used as a substrate, a Co-MOF sheet grows on the surface of the carbon paper, carbon nano tubes grow on the surface of the Co-MOF sheet, and cobalt cluster particles are distributed on the tube walls of the carbon nano tubes.
2. The cobalt-based multifunctional catalyst imitating a pine branch and leaf structure of claim 1, wherein the thickness of the Co-MOF sheet is 30-50 μm, the diameter of the carbon nanotube is 30-50nm, and the particle size of the cobalt cluster particle is 3-8 nm.
3. The preparation method of the cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii as claimed in claim 1, which comprises the following steps:
a: mixing melamine and ethanol, stirring by using a magnetic stirrer to obtain uniform melamine slurry, transferring the slurry into a graphite boat, and drying in a vacuum drying oven at constant temperature;
b: cutting carbon paper into size of 1cm × 0.8cm, sequentially ultrasonic cleaning with acetone, ethanol, and deionized water for 20min, and oven drying in a vacuum drying oven; performing plasma etching on the dried carbon paper, wherein the working frequency is 12-14MHz, the etching time is 5-15min, and placing the treated carbon paper in a glove box in argon atmosphere for later use;
c: respectively dissolving cobalt nitrate hexahydrate and dimethylimidazole in 25mL of deionized water, and magnetically stirring for 30-60min to obtain solutions a and b; pouring the solution a into the solution b, putting the cleaned carbon paper into the mixed solution, standing for 2-6h at room temperature, so that a cobalt-based metal organic metal framework structure (Co-MOF) grows on the carbon paper substrate, and marking the carbon paper obtained at the moment as Co-MOF/CP;
d: and (3) putting the graphite boat filled with the dried melamine in the step (A) and the Co-MOF/CP prepared in the step (C) into a tube furnace, heating to the temperature of 750-1000 ℃ in the nitrogen atmosphere, preserving the heat for 0.5-2h, and naturally cooling to the room temperature to obtain the cobalt-based multifunctional catalyst with the imitation black pine branch and leaf structure, wherein the heating rate is 1.5-2 ℃/min.
4. The preparation method of the cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii as claimed in claim 3, wherein the mass-to-volume ratio of the melamine to the ethanol in the step A is 1 mg: 1 mL.
5. The preparation method of the cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii as claimed in claim 3, wherein the melamine slurry in the step A is dried at the temperature of 50-80 ℃ for 2-4 h.
6. The method for preparing the cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii as claimed in claim 3, wherein the molar ratio of the cobalt nitrate hexahydrate to the dimethyl imidazole in the step C is 1: 5-9.
7. The preparation method of the cobalt-based multifunctional catalyst imitating the branch and leaf structure of the Pinus thunbergii as claimed in claim 3, wherein in the step D, the molar ratio of melamine to cobalt nitrate hexahydrate is 1: 0.2-0.4.
8. The method for preparing the cobalt-based multifunctional catalyst imitating the branches and leaves of the Pinus thunbergii as claimed in claim 3, wherein in the step D, the graphite boat containing the dried melamine and the Co-MOF/CP are sequentially placed along the direction from the air inlet to the air outlet of the tube furnace.
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| US20090075157A1 (en) * | 2004-10-06 | 2009-03-19 | Pak Chan-Ho | Carbon nanotube for fuel cell, nanocomposite comprising the same, method for making the same, and fuel cell using the same |
| CN112853374A (en) * | 2021-02-20 | 2021-05-28 | 闽江学院 | Nickel-iron oxygen evolution electrochemical catalyst for seawater electrolysis and preparation method and application thereof |
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|---|---|---|---|---|
| US20090075157A1 (en) * | 2004-10-06 | 2009-03-19 | Pak Chan-Ho | Carbon nanotube for fuel cell, nanocomposite comprising the same, method for making the same, and fuel cell using the same |
| CN112853374A (en) * | 2021-02-20 | 2021-05-28 | 闽江学院 | Nickel-iron oxygen evolution electrochemical catalyst for seawater electrolysis and preparation method and application thereof |
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| 周兴伟: "钴基MOF衍生多功能电催化剂的制备及其碱性条件下电催化性能的研究", 工程科技Ⅰ辑, no. 01, 15 January 2022 (2022-01-15), pages 13 - 30 * |
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