Lewis acid type cerium dioxide supported ruthenium catalyst as well as preparation method and application thereof
By preparing a Lewis acid-type ceria-loaded ruthenium catalyst, the problems of high catalyst cost and poor stability in hydrogen production by electrolysis of seawater were solved, and the efficient and low-cost HER reaction of seawater electrolysis was achieved.
Patent Information
- Application Number
- CN202510956057.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-11
- Publication Date
- 2025-09-26
AI Technical Summary
Existing catalysts for hydrogen production by electrolysis of seawater are expensive and have poor stability. The precious metal Pt is easily soluble, and the complex composition of seawater leads to catalyst poisoning, which shortens the catalyst lifespan.
Lewis acid-type ceria-supported ruthenium catalyst was prepared by combining hydrothermal loading and high-temperature calcination. CeO2 was used as a carrier to improve the stability and activity of Ru, and the catalytic performance was improved through the synergistic effect of CeO2 and Ru.
It achieves high catalytic activity, excellent selectivity and long-term stability in seawater electrolysis, reduces costs, is suitable for alkaline seawater electrolysis, and extends the service life of the catalyst.
Smart Images
Figure CN120700540A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of electrode material preparation, and in particular to a Lewis acid-type ceria-supported ruthenium catalyst, a preparation method thereof, and an application thereof. Background Art
[0002] Hydrogen is attracting widespread attention as a zero-carbon energy carrier. Compared to producing gray hydrogen from fossil fuels, hydrogen production from water and seawater electrolysis can be coupled with renewable energy. However, seawater electrolysis presents two challenges: high catalyst costs and the complex seawater environment. Currently, precious metal platinum (Pt)-based catalysts are commonly used as cathode catalysts for water electrolysis, but Pt is expensive. Non-precious metals are inactive and easily soluble. Ruthenium (Ru) possesses similar hydrogen bonding energies to Pt and exhibits significant catalytic activity, but it is easily deactivated by overoxidation at high potentials, and its poor stability significantly limits its application. Furthermore, seawater is complex, containing large amounts of calcium, magnesium, bromine, and chloride ions, which can poison the catalyst during the reaction and reduce its lifespan. Therefore, improving material stability, reducing overpotentials, and resisting seawater corrosion are key areas of research for ruthenium-based materials.
[0003] Cerium dioxide (CeO2) has become an ideal carrier for seawater electrolysis catalysts due to its Lewis acidity. CeO2 can adsorb and activate water molecules, promote proton supply, and thus improve the HER reaction kinetics. In addition, CeO2 exhibits excellent resistance to Cl in seawater environments. - corrosion ability, inhibiting the dissolution of Ru active sites, while the Lewis acid sites on the surface are - The competitive adsorption of Ru can further reduce the poisoning of Ru. Summary of the Invention
[0004] In view of this, the present application provides a Lewis acid-type ceria-supported ruthenium catalyst, a preparation method and application thereof. The present application adopts a strategy combining hydrothermal loading and high-temperature calcination to prepare a ceria-supported ruthenium catalyst, and applies it to the hydrogen evolution reaction in the electrolysis of seawater. The preparation method has certain application prospects for electrocatalysis, and has important research significance for promoting the industrialization process of ruthenium-based catalysts in water electrolysis, and can effectively overcome the defects of the above-mentioned existing technologies.
[0005] The first aspect of the present application provides a method for preparing a Lewis acid-type ceria-supported ruthenium catalyst, comprising the following steps:
[0006] (1) dissolving cerium nitrate hexahydrate and sodium hydroxide in water, stirring vigorously and then performing a hydrothermal reaction, washing and drying to obtain cerium dioxide;
[0007] (2) dissolving the cerium dioxide and ruthenium trichloride trihydrate in water, stirring vigorously and then performing a hydrothermal reaction, and washing and drying to obtain a precursor;
[0008] (3) Annealing the precursor to obtain a Lewis acid type ceria-supported ruthenium catalyst.
[0009] Preferably, in step (1), the usage ratio of the cerium nitrate hexahydrate, sodium hydroxide and water is (0.8~1) g: (9~10) g: 40 ml.
[0010] Preferably, in step (1), the hydrothermal reaction temperature is 120-160° C., and the hydrothermal reaction time is 12-18 h.
[0011] Preferably, in step (1), the vigorous stirring time is 1 h.
[0012] Preferably, in step (2), the usage ratio of cerium dioxide, ruthenium trichloride trihydrate and water is (40-50) mg: (5-20) mg: 50 ml.
[0013] Preferably, in step (2), the hydrothermal reaction temperature is 100-120° C., and the hydrothermal reaction time is 10-24 h.
[0014] Preferably, in step (2), the vigorous stirring time is 12 h.
[0015] Preferably, in step (3), the specific conditions of the annealing treatment are:
[0016] The heating rate is 1~10℃ / min, the annealing temperature is 300~500℃, and the holding time is 2~5 h.
[0017] The second aspect of the present application also provides a Lewis acid type ceria supported ruthenium catalyst, characterized in that it is a preparation method of the Lewis acid type ceria supported ruthenium catalyst obtained by the above method.
[0018] The third aspect of the present application also provides the use of the above-mentioned Lewis acid-type ceria-supported ruthenium catalyst in the HER reaction of water electrolysis.
[0019] Compared with the prior art, this application has the following beneficial effects:
[0020] 1. The present application provides a method for preparing a Lewis acid type ceria-supported ruthenium catalyst, which is based on a Lewis acid type ceria that is resistant to chlorine corrosion and has ultra-long durability, and is loaded with ruthenium with high HER activity. Through the synergistic effect between the ceria carrier and metallic ruthenium, the Ru / CeO2 catalyst achieves high catalytic activity, excellent selectivity and long-term stability in the seawater electrolysis system.
[0021] 2. The preparation method of the present application is simple, easy to operate, and low-cost. The prepared Ru / CeO2 catalyst has excellent electrochemical activity and ultra-long stability compared with other seawater electrolysis HER catalysts. The catalyst is suitable for alkaline seawater electrolysis and can exhibit excellent electrochemical performance in the seawater electrolysis HER reaction, providing a new research plan for the industrial application of water electrolysis. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] In order to more clearly illustrate the technical solutions in the present application or the prior art, the following briefly introduces the drawings required for use in the description of the present application or the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.
[0023] Figure 1 is the XRD pattern of the ceria-supported ruthenium catalyst (Ru / CeO2) prepared in Example 1;
[0024] Figure 2 HER polarization curves of the cerium dioxide supported ruthenium catalyst (Ru / CeO2) prepared in Example 1, the cerium dioxide CeO2 prepared in Comparative Example 1, and commercial Pt / C in 1 M KOH + seawater;
[0025] Figure 3 TEM image of cerium dioxide CeO2 prepared in Comparative Example 1;
[0026] Figure 4 TEM image of the ceria-supported ruthenium catalyst (Ru / CeO2) prepared in Example 1;
[0027] Figure 5 The ruthenium oxide supported catalyst (Ru / CeO2) prepared in Example 1 was -10 mA cm -2 Stability images at different current densities. DETAILED DESCRIPTION
[0028] To make the objectives, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making any creative efforts are within the scope of protection of this application.
[0029] Unless otherwise specified, the experimental methods used in the examples of this application are all conventional methods.
[0030] In the following examples and comparative examples, unless otherwise specified, all raw materials can be purchased commercially or prepared by conventional methods. Specifically, commercial Pt / C was purchased from Shanghai Hesen Electric Co., Ltd., model 20% platinum carbon HPT020.
[0031] Example 1
[0032] The preparation method of the Lewis acid type ceria-supported ruthenium catalyst provided in this embodiment comprises the following steps:
[0033] (1) Preparation of small-sized ceria: 0.8675 g of cerium nitrate hexahydrate and 9 g of sodium hydroxide were dissolved in 40 ml of water and stirred vigorously for 1 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 160°C for 16 h. The reacted sample was washed alternately with water and ethanol several times and dried in a 60°C forced air drying oven overnight to obtain small-sized ceria.
[0034] (2) Ruthenium loading: 40 mg of the cerium dioxide prepared in step (1) and 10 mg of ruthenium chloride trihydrate were dissolved in 50 ml of water and stirred vigorously for 12 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 100°C for 12 h. The reacted sample was washed alternately with water and ethanol and dried in a 60°C forced air drying oven overnight to obtain a precursor product.
[0035] (3) Preparation of ceria-supported ruthenium catalyst: The precursor product prepared in step (2) above was placed in a tube furnace, heated to 450°C at a heating rate of 5°C / min in an argon atmosphere, and kept at this temperature for 2 h.
[0036] Example 2
[0037] The preparation method of the ceria-supported ruthenium catalyst provided in this embodiment can refer to that in Example 1, except that the amount of supported ruthenium is changed.
[0038] The preparation method of the Lewis acid type ceria-supported ruthenium catalyst provided in this embodiment comprises the following steps:
[0039] (1) Preparation of small-sized ceria: 0.8675 g of cerium nitrate hexahydrate and 9 g of sodium hydroxide were dissolved in 40 ml of water and stirred vigorously for 1 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 160°C for 16 h. The reacted sample was washed alternately with water and ethanol several times and dried in a 60°C forced air drying oven overnight to obtain small-sized ceria.
[0040] (2) Ruthenium loading: 40 mg of the cerium dioxide prepared in step (1) and 5 mg of ruthenium chloride trihydrate were dissolved in 50 ml of water and stirred vigorously for 12 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 100°C for 12 h. The reacted sample was washed alternately with water and ethanol and dried in a 60°C forced air drying oven overnight to obtain a precursor product.
[0041] (3) Preparation of cerium dioxide catalyst: The precursor product prepared in step (1) above was placed in a tube furnace, heated to 450°C at a heating rate of 5°C / min in an argon atmosphere, and kept at this temperature for 2 h.
[0042] Example 3
[0043] The preparation method of the ceria-supported ruthenium catalyst provided in this embodiment can refer to that in Example 1, except that the amount of supported ruthenium is changed.
[0044] The preparation method of the Lewis acid type ceria-supported ruthenium catalyst provided in this embodiment comprises the following steps:
[0045] (1) Preparation of small-sized ceria: 0.8675 g of cerium nitrate hexahydrate and 9 g of sodium hydroxide were dissolved in 40 ml of water and stirred vigorously for 1 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 160°C for 16 h. The reacted sample was washed alternately with water and ethanol several times and dried in a 60°C forced air drying oven overnight to obtain small-sized ceria.
[0046] (2) Ruthenium loading: 40 mg of the cerium dioxide prepared in step (1) and 15 mg of ruthenium chloride trihydrate were dissolved in 50 ml of water and stirred vigorously for 12 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 100°C for 12 h. The reacted sample was washed alternately with water and ethanol and dried in a 60°C forced air drying oven overnight to obtain the precursor product.
[0047] (3) Preparation of ceria catalyst: The precursor products prepared in step (2) were placed in a tube furnace, heated to 450°C at a heating rate of 5°C / min in an argon atmosphere, and kept warm for 2 h.
[0048] Example 4
[0049] The preparation method of the ceria-supported ruthenium catalyst provided in this embodiment can refer to that in Example 1, except that the amount of supported ruthenium is changed.
[0050] The preparation method of the Lewis acid type ceria-supported ruthenium catalyst provided in this embodiment comprises the following steps:
[0051] (1) Preparation of small-sized ceria: 0.8675 g of cerium nitrate hexahydrate and 9 g of sodium hydroxide were dissolved in 40 ml of water and stirred vigorously for 1 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 160°C for 16 h. The reacted sample was washed alternately with water and ethanol several times and dried in a 60°C forced air drying oven overnight to obtain small-sized ceria.
[0052] (2) Ruthenium loading: 40 mg of the cerium dioxide prepared in step (1) and 20 mg of ruthenium chloride trihydrate were dissolved in 50 ml of water and stirred vigorously for 12 h. The mixture was then introduced into a 100 ml polytetrafluoroethylene-lined container and sealed in an oven for solvothermal reaction at 100°C for 12 h. The reacted sample was washed alternately with water and ethanol and dried in a 60°C forced air drying oven overnight to obtain a precursor product.
[0053] (3) Preparation of ceria catalyst: The precursor products prepared in step (2) were placed in a tube furnace, heated to 450°C at a heating rate of 5°C / min in an argon atmosphere, and kept warm for 2 h.
[0054] Comparative Example 1
[0055] The preparation method of the cerium dioxide catalyst provided in this comparative example can refer to Example 1, except that ruthenium is not loaded, and cerium dioxide CeO2 is obtained.
[0056] Test Case
[0057] (a) Elemental characterization of catalysts
[0058] X-ray diffraction was used to characterize the elemental composition of the ruthenium oxide supported on ceria catalyst ( Figure 1 ).from Figure 1 It can be seen that the prepared material corresponds to the standard card, which further confirms that the catalyst is Ru / CeO2.
[0059] (b) Cathode hydrogen evolution performance test
[0060] A three-electrode system was used to perform linear sweep tests in saturated 1 M KOH + seawater at a sweep rate of 5 mV / s. The prepared catalyst showed superior hydrogen evolution performance to that of commercial platinum-carbon catalysts under alkaline seawater conditions ( Figure 2 ).
[0061] (c) Catalyst morphology characterization
[0062] TEM images further revealed the structural morphology and characteristics of the prepared materials, such as Figure 3 、 Figure 4As shown in the figure, the prepared CeO2 has a small cubic structure, with small cubes surrounding larger cubes and a size of about 5-20 nm. After loading Ru, the Ru / CeO2 catalyst still maintains a cubic structure, with Ru loaded in the form of particles on the CeO2 surface, and the Ru loading is uniform.
[0063] (d) Stability test
[0064] The catalyst was tested by chronopotentiometry at -10 mA cm -2 The catalyst exhibited excellent stability under current density. Figure 5 ), and it ran stably for more than 700 h without obvious attenuation.
[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some or all of the technical features therein. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A method for preparing a Lewis acid type ceria-supported ruthenium catalyst, characterized in that: The following steps are involved: (1) dissolving cerium nitrate hexahydrate and sodium hydroxide in water, stirring vigorously and then performing a hydrothermal reaction, washing and drying to obtain cerium dioxide; (2) dissolving the cerium dioxide and ruthenium trichloride trihydrate in water, stirring vigorously and then performing a hydrothermal reaction, and washing and drying to obtain a precursor; (3) Annealing the precursor to obtain a Lewis acid type ceria-supported ruthenium catalyst.
2. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (1), the usage ratio of the cerium nitrate hexahydrate, sodium hydroxide and water is (0.8~1) g: (9~10) g: 40 ml.
3. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (1), the hydrothermal reaction temperature is 120-160° C., and the hydrothermal reaction time is 12-18 h.
4. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (1), the vigorous stirring time is 1 h.
5. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (2), the usage ratio of cerium dioxide, ruthenium trichloride trihydrate and water is (40-50) mg: (5-20) mg: 50 ml.
6. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (2), the hydrothermal reaction temperature is 100-120° C., and the hydrothermal reaction time is 10-24 h.
7. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (2), the vigorous stirring time is 12 h.
8. The method for preparing the Lewis acid type ceria-supported ruthenium catalyst according to claim 1, wherein: In step (3), the specific conditions of the annealing treatment are: The heating rate is 1~10℃ / min, the annealing temperature is 300~500℃, and the holding time is 2~5 h.
9. A Lewis acid type ceria-supported ruthenium catalyst, characterized in that: A method for preparing a Lewis acid-type ceria-supported ruthenium catalyst prepared by the method described in any one of claims 1 to 8.
10. Use of the Lewis acid type ceria-supported ruthenium catalyst according to claim 9 in HER reaction in water electrolysis.