Preparation of ruthenium-carbon nanosheet and application of ruthenium-carbon nanosheet in hydroxide reaction
By preparing ruthenium-carbon nanosheets, the problem of slow kinetics in the hydrogenation reaction in alkaline anion exchange membrane fuel cells was solved, achieving high catalytic activity and stability while reducing dependence on precious metals.
Patent Information
- Application Number
- CN202511571721.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-30
- Publication Date
- 2025-12-05
AI Technical Summary
The kinetics of the hydrogenation reaction in existing alkaline anion exchange membrane fuel cells are slow and rely on expensive platinum group metal catalysts, which limits their development.
Ruthenium-carbon nanosheets were prepared by dissolving a ruthenium source in a solvent, adding an alkali metal salt and deionized water, and then subjecting the mixture to magnetic stirring and Joule thermal shock to obtain ruthenium-carbon nanosheets with a sheet-like morphology. These nanosheets were then applied to the hydroxide reaction in an alkaline medium.
Ruthenium-carbon nanosheets exhibit high catalytic activity and stability in alkaline media, outperforming commercial Pt/C catalysts, and are suitable for hydrogenation reactions.
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Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of electrocatalysis, and in particular to a preparation of ruthenium carbon nanosheets and application thereof in hydrogen oxidation reaction. BACKGROUND
[0002] Over-exploitation of fossil fuels and the resulting environmental problems have become a bottleneck hindering global development. At present, traditional fossil energy is gradually depleted, while 80% of the global energy is still provided by fossil fuels (coal, oil and natural gas). Therefore, the growing energy demand and environmental problems require us to strengthen the research on clean energy conversion and storage technology. According to the World Energy Statistics Yearbook, China accounted for about 30.7% of the total global carbon emissions in 2020, so the emission reduction task in China is very difficult. In order to solve the above problems, we need to continuously develop new materials and new technologies and apply them to the energy market.
[0003] Hydrogen energy is considered as the most promising alternative energy to fossil fuels, and efficient utilization of hydrogen energy is the key direction of future energy development. Hydrogen-oxygen fuel cells can directly convert the chemical energy of hydrogen and oxygen into electrical energy, and are considered as ideal power generation devices due to their high energy conversion efficiency. Proton exchange membrane fuel cells (PEMFCs) and alkaline anion exchange membrane fuel cells (AEMFCs) are the two most promising hydrogen-oxygen fuel cells. Compared with PEMFCs, AEMFCs can use non-noble metal catalysts for cathode oxygen reduction reaction (ORR), thus being more cost-effective and commercially viable. However, the kinetics of the anode hydrogen oxidation reaction (HOR) under alkaline conditions is slow, being two to three orders of magnitude lower than that in acidic medium, and currently still relies on the use of a large amount of expensive and scarce platinum group metal (PGM) catalysts, which seriously limits the development of AEMFCs. Therefore, designing efficient HOR electrocatalysts with low PGM loading is expected to promote the further development of AEMFCs. SUMMARY
[0004] The technical problem to be solved by the present application is to provide a preparation of ruthenium carbon nanosheets and application thereof in hydrogen oxidation reaction, which shows excellent catalytic activity, stability and electrical conductivity.
[0005] The technical problem to be solved by the present application is solved by the following technical solution:
[0006] One of the objects of the present application is to provide a preparation method of ruthenium carbon nanosheets, comprising the following steps:
[0007] (1) Dissolve the ruthenium source in a solvent, then add an alkali metal salt and deionized water, and stir with a magnetic stirrer, and heat to evaporate to dryness to obtain a precursor;
[0008] (2) subjecting the precursor prepared above to joule heat shock in an inert gas atmosphere to obtain a product;
[0009] (3) subjecting the product obtained to washing, centrifugation and drying to obtain the ruthenium carbon nanosheet.
[0010] The second object of the present application is to provide a ruthenium carbon nanosheet prepared according to the preparation method described above.
[0011] The third object of the present application is to provide the application of the ruthenium carbon nanosheet described above in electrocatalytic hydrogen oxidation reaction.
[0012] The present application has the following beneficial effects: compared with the prior art, the present application provides a preparation method of ruthenium carbon nanosheet catalyst, the controllable sheet morphology of which makes it have a relatively broad application prospect, and it shows high catalytic activity, stability and conductivity in hydrogen oxidation reaction, and is especially suitable for hydrogen oxidation reaction in alkaline medium, and can provide practical guidance for the development of efficient ruthenium-based electrochemical catalysts. BRIEF DESCRIPTION OF DRAWINGS
[0013] Figure 1 and Figure 2 The structural characterization results of the JH Ru sample prepared in Example 1 of the present application are shown in the X-ray diffraction pattern and the transmission electron microscopy image.
[0014] Figures 3-8 The performance test results of the JH Ru sample prepared in Example 1 of the present application and the commercial Pt / C and commercial Ru / C in electrocatalytic hydrogen oxidation reaction are shown in the following table: Figure 3 HOR polarization curves at different rotation speeds in 0.1M KOH electrolyte saturated with H2; Figure 4 Koutecky-Levich plots obtained at 50mV overpotential; Figure 5 HOR Tafel plots; Figure 6 HOR polarization curves at 1600rpm rotation speed in 0.1M KOH electrolyte saturated with H2; Figure 7 Comparison of HOR catalytic activity before and after 1000 cycles of CV at 50mV overpotential and 1600rpm rotation speed; Figure 8 Current-time plots at 50mV overpotential. DETAILED DESCRIPTION
[0015] In order to make the technical means, creative features, purposes and effects realized by the present application easy to understand, the present application is further described below in combination with specific examples and drawings.
[0016] The present application provides a preparation method of ruthenium carbon nanosheet, which comprises the following steps:
[0017] (1) dissolving the ruthenium source in a solvent, then adding an alkali metal salt, adding deionized water, stirring with a magnetic stirrer, and heating to evaporate dry to obtain a precursor;
[0018] (2) subjecting the precursor prepared above to joule heat shock in an inert gas atmosphere to obtain a product;
[0019] (3) washing, centrifuging, and drying the product to obtain ruthenium carbon nanosheets.
[0020] Preferably, the ruthenium source is ruthenium acetylacetone.
[0021] Preferably, the solvent is anhydrous ethanol.
[0022] Preferably, the alkali metal salt is potassium bromide.
[0023] Preferably, the mass ratio of the ruthenium source to the alkali metal salt is 1:10.
[0024] Preferably, the current for the joule heat shock is 30-32 A, and the shock time is 5 s.
[0025] Preferably, the washing is deionized water washing.
[0026] The application also provides a ruthenium carbon nanosheet prepared according to the preparation method described above.
[0027] The application further provides an application of the ruthenium carbon nanosheet described above in electrocatalytic hydroxidation.
[0028] Preferably, the electrocatalytic hydroxidation is a hydroxidation reaction in an alkaline medium with 0.1 M KOH as an electrolyte.
[0029] Example 1
[0030] Preparation of ruthenium carbon nanosheets:
[0031] (1) dissolving 100 mg of ruthenium acetylacetone in 20 ml of anhydrous ethanol, then adding 1000 mg of potassium bromide, and adding 20 ml of deionized water, stirring with a magnetic stirrer, and heating to evaporate dry to obtain a precursor.
[0032] (2) placing 100 mg of the precursor prepared above in a carbon boat and subjecting to a 5 s shock under a nitrogen atmosphere at a current of 32 A to obtain a product.
[0033] (3) washing, centrifuging, and drying the product with deionized water to obtain ruthenium carbon nanosheets.
[0034] The JH Ru sample prepared in Example 1 was subjected to structural characterization, and the results are shown in Figure 1 、 Figure 2 .
[0035] Figure 1 All the diffraction peaks appeared in the sample correspond well to the diffraction peaks of pure fcc Ru and pure hcp Ru; Figure 2 The JH Ru sample shows a nanosheet structure morphology;
[0036] Example 2
[0037] Application research of the JH Ru sample prepared in Example 1 as a catalyst in electrocatalytic hydrogen oxidation:
[0038] The HOR electrocatalytic test was performed on an electrochemical workstation using a standard three-electrode system. A 1M KOH solution containing hydrogen was used as the electrolyte, and a rotating disc electrode (RDE) modified with JH Ru (4mg of the JH Ru sample prepared in Example 1 was dispersed in 1000μL of ethanol containing 40uL of 5wt% Nafion, and an ink was prepared by ultrasonicating for 1h; then 7.5μL of the ink was dropped onto a polished rotating disc electrode to obtain the working electrode) was used as the working electrode, a platinum wire was used as the counter electrode, and a Hg / HgO electrode was used as the reference electrode.
[0039] A control example was also set up in which a commercial Pt / C was used instead of JH Ru as a catalyst to prepare the working electrode. The Pt content in the Pt / C was 20%, and the other conditions were the same as above.
[0040] As shown in Figure 3 and Figure 4 , the kinetic current density j of the RDE and ω 1 / 2 showed a linear relationship at a 50mV overpotential, and the fitted straight line was represented by the Koutecky-Levich equation. The slope was 4.61cm 2 ·mA -1 ·s -1 / 2 , which was close to the theoretical value (4.87cm 2 ·mA -1 ·s -1 / 2 ) for double-electron HOR.
[0041] As can be seen from Figure 5 and Figure 6 , the HOR catalytic activity of JH Ru in alkaline medium was significantly better than that of Pt / C.
[0042] As can be seen from Figure 7 , JH Ru had extremely high stability in alkaline medium.
[0043] As can be seen from Figure 8 , the HOR catalytic activity of JH Ru in alkaline medium could be maintained stable within 24h.
[0044] In summary, the prepared JH Ru has better HOR catalytic activity in alkaline medium than the commercial Pt / C catalyst and good stability.
[0045] The above shows and describes the basic principles and main features of the present application and the advantages of the present application. Those skilled in the art should understand that the present application is not limited to the above-mentioned embodiments, and the above-mentioned embodiments and descriptions in the specification are only to illustrate the principles of the present application. Without departing from the spirit and scope of the present application, various changes and improvements can be made to the present application, and these changes and improvements all fall within the scope of the claimed present application. The scope of protection of the present application is defined by the appended claims and their equivalents.
Claims
1. A method for preparing ruthenium-carbon nanosheets, characterized in that, The method comprises the following steps: (1) dissolving a ruthenium source in a solvent, then adding an alkali metal salt, adding deionized water, stirring with a magnetic stirrer, and heating to evaporate dry to obtain a precursor; (2) subjecting the prepared precursor to joule heat shock in an inert gas atmosphere to obtain a product; (3) washing, centrifuging and drying the obtained product to obtain ruthenium carbon nanosheets.
2. The production method according to claim 1, characterized by: The ruthenium source is ruthenium acetylacetone.
3. The production method according to claim 1, wherein: The solvent is anhydrous ethanol.
4. The production method according to claim 1, wherein: The alkali metal salt is potassium bromide.
5. The production method according to claim 1, wherein: The mass ratio of the ruthenium source to the alkali metal salt is 1:
10.
6. The production method according to claim 1, wherein: The current of the joule heat shock is 30-32 A, and the shock time is 5 s.
7. The production method according to claim 1, wherein: The washing is deionized water washing.
8. The ruthenium carbon nanosheets prepared by the preparation method according to any one of claims 1-7.
9. The ruthenium carbon nanosheets according to claim 8 are used in electrocatalytic hydrogen oxidation reactions.
10. Use according to claim 9, wherein: The electrocatalytic hydrogen oxidation reaction is a hydrogen oxidation reaction in an alkaline medium with 0.1M KOH as an electrolyte.