A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a carrier
By loading platinum nanoparticles and polypyrrole gel onto a porous gel composite carbonized membrane, a porous Pt nanoparticle network is formed, which solves the problem of easy aggregation of noble metal nanoparticles in the catalyst, improves the stability and activity of the catalyst, and enhances the catalytic performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SUZHOU BIDING NEW MATERIAL TECH CO LTD
- Filing Date
- 2024-01-24
- Publication Date
- 2026-08-04
AI Technical Summary
Noble metal nanoparticles tend to aggregate, dissolve, and migrate in catalysts, leading to reduced catalytic activity and low loading, which affects the stability and efficiency of the catalyst.
Using a porous gel composite carbonized membrane as a carrier, an electrospun membrane was prepared by electrospinning technology, and platinum nanoparticles were loaded on its surface. Combined with polypyrrole gel, a highly efficient catalyst was formed. The electronic structure and physical properties were improved by doping with atoms such as nitrogen and cobalt, forming a porous Pt nanoparticle network.
It improves the utilization rate and catalytic activity of precious metals, enhances the active sites of the catalyst, and improves the methanol oxidation capacity and catalytic performance.
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Figure BDA0004679119770000081
Abstract
Description
Technical Field
[0001] This invention relates to the field of noble metal catalysts, and more specifically to a method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support. Background Technology
[0002] Catalysis and catalysts are core technologies in petrochemicals and fine chemicals. More than 60% of the world's chemicals and over 90% of chemical processes are related to catalysis and catalysts; it can be said that without catalytic technology, there would be no modern petrochemicals and fine chemicals. Among numerous catalytic materials, noble metal catalysts have attracted much attention due to their unique physicochemical properties and are widely used in catalytic reactions such as hydrogenation, dehydrogenation, cracking, isomerization, oxidation, and cyclization. Noble metals consist of eight elements: gold (Au), silver (Ag), and the platinum group metals Pt, Pd, Os, Ir, Ru, and Rh. When nanoscale noble metal particles exist on the catalyst surface, they have a higher surface-to-volume ratio compared to an equivalent amount of bulk metal, thus giving the catalyst higher catalytic activity and selectivity. Noble metal catalysts also have the characteristics of good stability and easy reusability.
[0003] Because metal nanoparticles have high surface energy, they are prone to aggregation. Furthermore, during the reaction process, metal nanoparticles easily dissolve and migrate, leading to reduced catalyst activity and decreased utilization of precious metals. Therefore, loading metal nanoparticles onto suitable support materials can support the active material, significantly improve the catalyst's dispersibility and stability, and enhance the utilization of precious metals. Summary of the Invention
[0004] The technical problem to be solved: The purpose of this invention is to provide a method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support. The method involves preparing an electrospun membrane, carbonizing it to obtain a cobalt-nitrogen-doped carbonized membrane, and using this membrane as a support to load platinum nanoparticles and composite them with polypyrrole gel to obtain a catalyst with high catalytic efficiency.
[0005] Technical solution: A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support, comprising the following steps:
[0006] S1. The porous carbonized membrane is immersed in H2PtCl4 solution to obtain a Pt-loaded carbonized membrane;
[0007] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution;
[0008] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution;
[0009] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution;
[0010] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the carbonized film loaded with Pt, and ultrasonically homogenized to form a gel;
[0011] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react, thereby obtaining a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0012] Preferably, the method for preparing the porous carbonized membrane in step S1 is as follows:
[0013] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution. Perform electrospinning on the spinning solution to obtain an electrospun membrane.
[0014] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution;
[0015] S13. Immerse the electrospun membrane in the solution prepared in step S12 to obtain an electrospun membrane with surface polymerized polydopamine and cobalt; S14. After washing and drying the electrospun membrane prepared in step S13, place the completely dried membrane into a vacuum tube furnace for calcination to obtain a porous carbonized membrane.
[0016] Preferably, the concentration of the spinning solution in step S11 is 8-10 wt%, and the porosity of the electrospun membrane is 88-93%.
[0017] Preferably, in step S12, the concentration of cobalt chloride in the mixed solution is 0.01-0.03 wt%, and the concentration of dopamine hydrochloride is 0.2-0.4 wt%.
[0018] Preferably, the immersion time in step S13 is 60-100 min.
[0019] Preferably, the calcination parameters in step S14 are: heating from room temperature to 250-300°C in air at 5-6°C / min and holding for 3-4 hours; then heating to 780-820°C in nitrogen at 5-7°C / min and holding for 60-90 minutes.
[0020] Preferably, the concentration of the H2PtCl4 solution in step S1 is 0.005-0.015 g / mL.
[0021] Preferably, the concentration of the silver nitrate solution is 1.2-1.5 mg / mL, the concentration of the pyrrole solution is 90-110 mg / mL, and the concentration of the ferric chloride solution is 500-1000 mg / mL.
[0022] Preferably, in step S5, the volume ratio of the silver nitrate solution to the pyrrole solution is 1:1, and the proportion of the Pt-loaded carbonized film in the gel is 60-75% vt.
[0023] Beneficial effects: The catalyst prepared by the method of the present invention has the following advantages:
[0024] 1. In this invention, electrospun membranes and gel porous materials are used as carriers to prepare Pt catalysts with ultra-high loading ratios. First, an electrospun membrane is prepared, and cobalt-containing polydopamine is loaded on the surface of the electrospun membrane. After carbonization, a carbon material doped with nitrogen, cobalt, and other atoms is formed, which changes the electronic structure of the carbon material and affects its chemical reactivity and electrical conductivity. At the same time, the intrinsic physical / chemical properties of the material can be well maintained. In addition, the incorporation of heteroatoms is also beneficial to anchoring active metal nanoparticles, reducing their particle size, thereby improving catalytic activity.
[0025] 2. In this invention, the polypyrrole gel formed by oxidizing the gel after adding a carbonized film to the gel material has a large specific surface area and large mesopores. These mesopores are interconnected to form a channel structure, which facilitates the rapid transport of reactants and products. Nitrogen doping also promotes the high dispersion of platinum nanoparticles, thereby increasing the active sites of the catalyst and enhancing its methanol oxidation capacity. Simultaneously, the carbonized film is contained within the gel, and its surface forms a porous, interconnected network of Pt nanoparticles with numerous Pt interfaces, effectively improving the catalytic activity. Detailed Implementation
[0026] The present invention will be further described below with reference to embodiments. These embodiments are illustrative of the present invention, but the present invention is not limited to these embodiments:
[0027] Example 1
[0028] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0029] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.005 g / mL to obtain a Pt-loaded carbonized membrane;
[0030] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.2 mg / mL;
[0031] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 110 mg / mL;
[0032] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 500 mg / mL;
[0033] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film. The volume ratio of silver nitrate solution to pyrrole solution is 1:1. The mixture is ultrasonically homogenized to form a gel. The proportion of the Pt-loaded carbonized film in the gel is 60vt%.
[0034] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0035] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0036] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution with a concentration of 8wt%. Perform electrospinning on the spinning solution to obtain an electrospun membrane with a porosity of 88.9%.
[0037] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a concentration of 0.01 wt% for cobalt chloride and 0.2 wt% for dopamine hydrochloride.
[0038] S13. Immerse the electrospun membrane in the solution prepared in step S12 for 60 min to obtain an electrospun membrane with surface polymerized polydopamine and cobalt.
[0039] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 300°C in air at 5°C / min and holding for 3 hours; then heating to 780°C in nitrogen at 5°C / min and holding for 60 minutes to obtain a porous carbonized membrane.
[0040] Example 2
[0041] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0042] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.015 g / mL to obtain a Pt-loaded carbonized membrane;
[0043] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.5 mg / mL;
[0044] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 90 mg / mL;
[0045] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 1000 mg / mL;
[0046] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film with a volume ratio of 1:1. The mixture is ultrasonically homogenized to form a gel, and the Pt-loaded carbonized film accounts for 75% of the gel.
[0047] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0048] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0049] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution with a concentration of 10wt%. Perform electrospinning on the spinning solution to obtain an electrospun membrane with a porosity of 93%.
[0050] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a concentration of 0.03 wt% for cobalt chloride and 0.4 wt% for dopamine hydrochloride.
[0051] S13. Immerse the electrospun membrane in the solution prepared in step S12 for 100 min to obtain an electrospun membrane with surface polymerized polydopamine and cobalt.
[0052] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 250°C in air at 6°C / min and holding for 4 hours; then heating to 820°C in nitrogen at 7°C / min and holding for 90 minutes to obtain a porous carbonized membrane.
[0053] Example 3
[0054] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0055] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.008 g / mL to obtain a Pt-loaded carbonized membrane;
[0056] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.3 mg / mL;
[0057] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 95 mg / mL;
[0058] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 900 mg / mL;
[0059] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film. The volume ratio of silver nitrate solution to pyrrole solution is 1:1. The mixture is ultrasonically homogenized to form a gel. The proportion of the Pt-loaded carbonized film in the gel is 65vt%.
[0060] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0061] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0062] S11. Polyacrylonitrile is dissolved in N,N-dimethylformamide and stirred until completely dissolved to obtain a spinning solution with a concentration of 8wt%. The spinning solution is electrospun to obtain an electrospun membrane with a porosity of 92.5%.
[0063] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a cobalt chloride concentration of 0.015 wt% and a dopamine hydrochloride concentration of 0.25 wt%. S13. The electrospun membrane is immersed in the solution prepared in step S12 for 70 min to obtain an electrospun membrane with surface-polymerized polydopamine and cobalt.
[0064] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 260°C in air at 5°C / min and holding for 3 hours; then heating to 800°C in nitrogen at 5°C / min and holding for 70 minutes to obtain a porous carbonized membrane.
[0065] Example 4
[0066] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0067] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.012 g / mL to obtain a Pt-loaded carbonized membrane;
[0068] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.4 mg / mL;
[0069] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 105 mg / mL;
[0070] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 600 mg / mL;
[0071] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film. The volume ratio of silver nitrate solution to pyrrole solution is 1:1. The mixture is ultrasonically homogenized to form a gel. The proportion of the Pt-loaded carbonized film in the gel is 70vt%.
[0072] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0073] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0074] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution with a concentration of 10wt%. Perform electrospinning on the spinning solution to obtain an electrospun membrane with a porosity of 90.2%.
[0075] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a cobalt chloride concentration of 0.025 wt% and a dopamine hydrochloride concentration of 0.35 wt%. S13. The electrospun membrane is immersed in the solution prepared in step S2 for 90 min to obtain an electrospun membrane with surface polymerized polydopamine and cobalt.
[0076] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 290°C in air at 6°C / min and holding for 3 hours; then heating to 780°C in nitrogen at 7°C / min and holding for 80 minutes to obtain a porous carbonized membrane.
[0077] Example 5
[0078] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0079] S1. The porous carbonized membrane was immersed in a 0.01 g / mL H2PtCl4 solution to obtain a Pt-loaded carbonized membrane;
[0080] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.35 mg / mL;
[0081] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 100 mg / mL;
[0082] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 800 mg / mL;
[0083] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film with a volume ratio of 1:1. The mixture is ultrasonically homogenized to form a gel, and the Pt-loaded carbonized film accounts for 68% of the gel.
[0084] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0085] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0086] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution with a concentration of 10wt%. Perform electrospinning on the spinning solution to obtain an electrospun membrane with a porosity of 91.5%.
[0087] S12. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a concentration of 0.02 wt% for cobalt chloride and 0.3 wt% for dopamine hydrochloride.
[0088] S13. Immerse the electrospun membrane in the solution prepared in step S12 for 80 min to obtain an electrospun membrane with surface polymerized polydopamine and cobalt.
[0089] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 280°C in air at 5°C / min and holding for 3.5 h; then heating to 800°C in nitrogen at 6°C / min and holding for 80 min to obtain a porous carbonized membrane.
[0090] Comparative Example 1
[0091] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0092] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.012 g / mL to obtain a Pt-loaded carbonized membrane;
[0093] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.4 mg / mL;
[0094] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 105 mg / mL;
[0095] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 600 mg / mL;
[0096] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film. The volume ratio of silver nitrate solution to pyrrole solution is 1:1. The mixture is ultrasonically homogenized to form a gel. The proportion of the Pt-loaded carbonized film in the gel is 70vt%.
[0097] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0098] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0099] S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution with a concentration of 10wt%. Perform electrospinning on the spinning solution to obtain an electrospun membrane with a porosity of 90.2%.
[0100] S12. After washing and drying the electrospun membrane prepared in step S11, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 290°C in air at 6°C / min and holding for 3 hours; then heating to 780°C in nitrogen at 7°C / min and holding for 80 minutes to obtain a porous carbonized membrane.
[0101] Comparative Example 2
[0102] A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support includes the following steps:
[0103] S1. The porous carbonized membrane was immersed in a H2PtCl4 solution with a concentration of 0.008 g / mL to obtain a Pt-loaded carbonized membrane;
[0104] S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution with a concentration of 1.3 mg / mL;
[0105] S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution with a concentration of 95 mg / mL;
[0106] S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution with a concentration of 900 mg / mL;
[0107] S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the Pt-loaded carbonized film. The volume ratio of silver nitrate solution to pyrrole solution is 1:1. The mixture is ultrasonically homogenized to form a gel. The proportion of the Pt-loaded carbonized film in the gel is 65vt%.
[0108] S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support.
[0109] The method for preparing the porous carbonized membrane in step S1 is as follows:
[0110] S11. Polyacrylonitrile is dissolved in N,N-dimethylformamide and stirred until completely dissolved to obtain a spinning solution with a concentration of 8wt%. The spinning solution is electrospun to obtain an electrospun membrane with a porosity of 92.5%.
[0111] S12. Add dopamine hydrochloride to Tris hydrochloride buffer solution and stir to dissolve, to obtain a 0.25wt% dopamine hydrochloride solution;
[0112] S13. Immerse the electrospun membrane in the solution prepared in step S12 for 70 min to obtain an electrospun membrane with dopamine loaded on its surface.
[0113] S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 260°C in air at 5°C / min and holding for 3 hours; then heating to 800°C in nitrogen at 5°C / min and holding for 70 minutes to obtain a porous carbonized membrane.
[0114] Comparative Example 3
[0115] A method for preparing a platinum-based catalyst supported on a carbonized film includes the following steps:
[0116] S1. Polyacrylonitrile was dissolved in N,N-dimethylformamide and stirred until completely dissolved to obtain a spinning solution with a concentration of 8wt%. The spinning solution was electrospun to obtain an electrospun membrane with a porosity of 92.6%.
[0117] S2. Cobalt chloride is dissolved in Tris hydrochloric acid buffer solution, and then dopamine hydrochloride is added to the buffer solution and stirred to dissolve, resulting in a mixed solution with a concentration of 0.01 wt% for cobalt chloride and 0.2 wt% for dopamine hydrochloride.
[0118] S3. Immerse the electrospun membrane in the solution prepared in step S12 for 60 min to obtain an electrospun membrane with surface polymerized polydopamine and cobalt.
[0119] S4. After washing and drying the electrospun membrane prepared in step S3, the completely dried membrane is placed in a vacuum tube furnace for calcination. The calcination parameters are as follows: heating from room temperature to 300°C in air at 5°C / min and holding for 3 hours; then heating to 780°C in nitrogen at 5°C / min and holding for 60 minutes to obtain a porous carbonized membrane.
[0120] S5. The porous carbonized membrane is immersed in a 0.005 g / mL H2PtCl4 solution to obtain a Pt-loaded carbonized membrane, which is then added to a hydrazine hydrate solution to react and obtain a platinum-based catalyst with the carbonized membrane as the support.
[0121] Test indicators for the hydrogenation performance of platinum-based catalysts supported by porous gel composite carbonized membranes
[0122]
[0123] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the scope of protection of this invention.
Claims
1. A method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support, characterized in that, Includes the following steps: S1. The porous carbonized membrane is immersed in H2PtCl4 solution to obtain a Pt-loaded carbonized membrane; S2. Add silver nitrate to anhydrous ethanol, stir and dissolve evenly to obtain a silver nitrate solution; S3. Dissolve pyrrole in anhydrous ethanol to obtain a pyrrole solution; S4. Dissolve ferric chloride in anhydrous ethanol to obtain a ferric chloride solution; S5. Silver nitrate solution and pyrrole solution are simultaneously poured onto the carbonized film loaded with Pt, and ultrasonically homogenized to form a gel; S6. Add the ferric chloride solution prepared in step S4 to the gel prepared in step S5, let it stand for oxidation, and then add it to the hydrazine hydrate solution to react and obtain a platinum-based catalyst with a porous gel composite carbonized membrane as the support. The method for preparing the porous carbonized membrane in step S1 is as follows: S11. Dissolve polyacrylonitrile in N,N-dimethylformamide and stir until completely dissolved to obtain a spinning solution. Perform electrospinning on the spinning solution to obtain an electrospinned membrane. S12. Cobalt chloride is added to Tris hydrochloric acid buffer solution and dissolved. Then, dopamine hydrochloride is added to the buffer solution and stirred until dissolved to obtain a mixed solution. S13. Immerse the electrospun membrane in the solution prepared in step S12 to obtain an electrospun membrane with surface polymerized polydopamine and cobalt; S14. After washing and drying the electrospun membrane prepared in step S13, the completely dried membrane is placed in a vacuum tube furnace for calcination to obtain a porous carbonized membrane.
2. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: In step S11, the concentration of the spinning solution is 8-10 wt%, and the porosity of the electrospinning membrane is 88-93%.
3. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: In step S12, the concentration of cobalt chloride in the mixed solution is 0.01-0.03 wt%, and the concentration of dopamine hydrochloride is 0.2-0.4 wt%.
4. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: The immersion time in step S13 is 60-100 minutes.
5. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that, The calcination parameters in step S14 are as follows: heat from room temperature to 250-300°C in air at a rate of 5-6°C / min and hold for 3-4 hours; then heat to 780-820°C in nitrogen at a rate of 5-7°C / min and hold for 60-90 minutes.
6. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: In step S1, the concentration of the H2PtCl4 solution is 0.005-0.015 g / mL.
7. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: The concentration of the silver nitrate solution is 1.2-1.5 mg / mL, the concentration of the pyrrole solution is 90-110 mg / mL, and the concentration of the ferric chloride solution is 500-1000 mg / mL.
8. The method for preparing a platinum-based catalyst using a porous gel composite carbonized membrane as a support according to claim 1, characterized in that: In step S5, the volume ratio of silver nitrate solution to pyrrole solution is 1:1.