Manganese-doped ruthenium oxide nano-catalyst, preparation method thereof, electrode and water electrolysis hydrogen production device

Abstract

The invention discloses a manganese-doped ruthenium oxide nano-catalyst, a preparation method thereof, an electrode and a water electrolysis hydrogen production device, and relates to the technical field of catalytic materials. The molar ratio of ruthenium to manganese in the catalyst is (5-9): 1; the average particle size of the catalyst is 6-8 nm. The manganese element is introduced to construct a stable composite structure, the structural stability is greatly improved while high intrinsic activity is maintained, in addition, good oxygen evolution and corrosion resistance are achieved, water oxidation of the acid electrolyte is driven at a low potential, good stability is maintained, and the service life of the acid electrolyte is prolonged. And the defect of poor stability of a commercial ruthenium oxide catalyst in an acid medium is overcome. The catalyst can well adapt to large-scale hydrogen production application in the future, and reaches the application standard of clean energy in the future. The preparation method belongs to one-pot molten salt synthesis, is simple, convenient and efficient in preparation, and provides a key material solution for an efficient and long-life proton exchange membrane water electrolysis hydrogen production technology.

Description

Technical Field

[0001] This invention relates to the field of catalytic materials technology, and more specifically, to manganese-doped ruthenium oxide nanocatalysts, their preparation methods, electrodes, and water electrolysis hydrogen production devices. Background Technology

[0002] Proton exchange membrane (PEM) water electrolysis is considered a promising green hydrogen production technology due to its high energy efficiency and high current density; however, the slow kinetics of the acidic oxygen evolution reaction at the anode severely limit the overall hydrogen production efficiency. While commercial ruthenium oxide catalysts possess initial activity, they are highly susceptible to corrosion and dissolution under strong acidic and high-potential environments, resulting in severely insufficient stability. This irreversible catalyst deactivation not only increases system maintenance costs but also significantly restricts the long-term operational stability and commercial application prospects of PEM water electrolysis units.

[0003] In view of this, the present invention is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide a manganese-doped ruthenium oxide nanocatalyst, its preparation method, electrode, and water electrolysis hydrogen production device to solve or improve the above-mentioned technical problems.

[0005] This invention is implemented as follows: In a first aspect, the present invention provides a manganese-doped ruthenium oxide nanocatalyst, wherein the molar ratio of ruthenium to manganese in the catalyst is (5-9):1; and the average particle size of the catalyst is 6nm-8nm.

[0006] Secondly, the present invention provides a method for preparing a manganese-doped ruthenium oxide nanocatalyst as described in any of the foregoing embodiments, comprising the following steps: Ruthenium source, manganese source and molten salt are mixed in proportion to obtain precursor mixture; The precursor mixture was heated to 340℃-360℃ in air at a heating rate of 1℃ / min-5℃ / min to carry out a molten salt reaction. The reaction product was post-processed to obtain manganese-doped ruthenium oxide nanocatalyst.

[0007] Thirdly, the present invention provides an electrode, wherein the catalytic active layer of the electrode comprises a manganese-doped ruthenium oxide nanocatalyst as described in any of the foregoing embodiments or a manganese-doped ruthenium oxide nanocatalyst prepared by any of the foregoing embodiments.

[0008] Fourthly, the present invention provides an electrolytic water hydrogen production device, wherein the anode of the electrolytic water hydrogen production device includes the electrode as described in the foregoing embodiments.

[0009] The present invention has the following beneficial effects: The manganese-doped ruthenium oxide nanocatalyst provided in this invention constructs a stable composite structure by introducing manganese. While maintaining high intrinsic activity, its structural stability is significantly improved. Furthermore, it exhibits excellent oxygen evolution and corrosion resistance, driving water oxidation in acidic electrolytes at relatively low potentials while maintaining good stability. This overcomes the poor stability of commercial ruthenium oxide catalysts in acidic media. This catalyst is well-suited for future large-scale hydrogen production applications and meets the standards for future clean energy applications.

[0010] The preparation method belongs to the one-pot molten salt synthesis, which is simple and efficient, and provides a key material solution for efficient and long-life proton exchange membrane water electrolysis hydrogen production technology. Attached Figure Description

[0011] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 These are the results of electrochemical testing; Figure 2 These are the results of the acid stability test; Figure 3 Manganese-doped ruthenium oxide nanocatalysts containing different proportions of Ru and Mn were prepared at 50 mA·cm⁻¹ -2 Stability test results; Figure 4 TEM test results and particle size distribution analysis of the manganese-doped ruthenium oxide nanocatalyst prepared in Example 1; Figure 5 TEM test results and particle size distribution analysis of the catalyst prepared in Comparative Example 1; Figure 6 The XRD test results are for the catalysts prepared in Example 1 and Comparative Examples 1-2. Detailed Implementation

[0013] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0014] In a first aspect, the present invention provides a manganese-doped ruthenium oxide nanocatalyst, wherein the molar ratio of ruthenium to manganese in the catalyst is (5-9):1; and the average particle size of the catalyst is 6nm-8nm.

[0015] In an optional embodiment, the molar ratio of ruthenium to manganese in the catalyst is (7-8):1.

[0016] For example, the molar ratio of ruthenium to manganese can be selected from any one of 7:1, 7.2:1, 7.4:1, 7.6:1 and 8:1, or other values ​​in the range of (7-8):1.

[0017] In an optional embodiment, the ruthenium source is selected from at least one of ruthenium chloride, ruthenium nitrate, ruthenium acetate, carbonyl compounds of ruthenium, and acetylacetone compounds of ruthenium.

[0018] In the optimal implementation, the ruthenium source is ruthenium chloride.

[0019] In an optional embodiment, the manganese source is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, manganese nitrate, manganese oxalate, and manganese acetylacetone compounds.

[0020] In the optimal implementation, the manganese source is manganese acetate.

[0021] Secondly, the present invention provides a method for preparing a manganese-doped ruthenium oxide nanocatalyst as described in any of the foregoing embodiments, comprising the following steps: Ruthenium source, manganese source and molten salt are mixed in proportion to obtain precursor mixture; The precursor mixture was heated to 340℃-360℃ in air at a heating rate of 1℃ / min-5℃ / min to carry out a molten salt reaction. The reaction product was post-processed to obtain manganese-doped ruthenium oxide nanocatalyst.

[0022] It should be noted that the preparation method of manganese-doped ruthenium oxide nanocatalyst belongs to the one-pot molten salt method, in which manganese element is uniformly doped into the ruthenium oxide lattice to form the morphology and structure of nanoparticles.

[0023] In an optional embodiment, the preparation of the precursor mixture includes the following steps: ruthenium source, manganese source, and molten salt are mixed together in an agate mortar in a specific ratio, followed by grinding for 15-25 minutes to ensure thorough and uniform mixing of all substances. In other embodiments of the invention, other experimental equipment can be selected for the mixing process as needed. Grinding helps to reduce the particle size of the materials while ensuring more thorough mixing. The grinding method can be selected appropriately based on the actual situation, using mechanical equipment or manual grinding.

[0024] In an optional embodiment, the molten salt is selected from at least one of alkali metal nitrates and alkali metal carbonates.

[0025] By subjecting the precursor mixture to a single high-temperature treatment, the reaction, crystallization, and even the formation of a specific morphology can be completed simultaneously. Molten salt provides a high-temperature liquid environment (typically >300°C) for the preparation of manganese-doped ruthenium oxide nanocatalysts, which greatly improves the diffusion rate of reactant ions, promotes the occurrence of high-temperature solid-phase reactions, and enables the rapid formation of crystalline phases that are difficult to synthesize under conventional conditions or require long-term heat treatment. This is beneficial for the formation of thermodynamically stable crystalline phases, resulting in catalyst materials with good crystallinity and few defects.

[0026] The present invention does not impose a particular limitation on the amount of molten salt used, but makes reasonable adjustments based on the amount of ruthenium source and manganese source used, specifically to completely cover the ruthenium source and manganese source.

[0027] For example, the molten salt may be selected from sodium nitrate, potassium nitrate, potassium carbonate, and sodium carbonate, etc.

[0028] In an optional embodiment, the temperature of the molten salt reaction is 350℃-360℃, and the time is 15min-25min; Optionally, the temperature of the molten salt reaction is 350℃-360℃, and the time is 20min-25min.

[0029] In the optimal implementation, the molten salt reaction is carried out at a temperature of 350°C for 20 minutes.

[0030] In this embodiment of the invention, the molten salt reaction involves first placing the precursor mixture in a corundum crucible, and then transferring it into a box-type muffle furnace for reaction. In other embodiments of the invention, crucibles and equipment of different materials can be selected for the molten salt reaction as needed.

[0031] In an optional embodiment, the post-processing includes: naturally cooling the reaction product to room temperature, washing with water to remove molten salt, and freeze-drying.

[0032] Specifically, post-processing includes the following steps: The cooled reaction product was removed and subjected to washing and drying. The washing process was as follows: the reaction product was placed in a beaker, a large amount of deionized water was added, and the mixture was repeatedly washed using a vacuum filtration system and a polyethersulfone organic filter membrane. This process continued until the filtrate was tested with 0.1 mol / L silver nitrate (AgNO3) solution and no white precipitate was produced, thus ensuring the presence of any possible chloride ions (Cl...). - The ions are completely removed. The polyethersulfone organic filter membrane has a diameter of 0.22 μm. In other embodiments of the present invention, other diameters may be selected as needed.

[0033] The drying process is as follows: The cleaned wet filter cake is freeze-dried, first by deep freezing at -50°C for 12 hours, then transferred to a freeze dryer and continuously dried for 24 hours under conditions where the cold trap temperature is below -50°C and the vacuum pressure in the drying chamber is below 10 Pa, ultimately obtaining black manganese-doped ruthenium oxide nanocatalyst powder. In other embodiments of the present invention, other drying methods can be selected as needed, or the technical parameters of freeze-drying can be reasonably adjusted.

[0034] Thirdly, the present invention provides an electrode, wherein the catalytic active layer of the electrode comprises a manganese-doped ruthenium oxide nanocatalyst as described in any of the foregoing embodiments or a manganese-doped ruthenium oxide nanocatalyst prepared by any of the foregoing embodiments.

[0035] Fourthly, the present invention provides an electrolytic water hydrogen production device, wherein the anode of the electrolytic water hydrogen production device includes the electrode as described in the foregoing embodiments.

[0036] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0037] Example 1 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which is prepared by the following steps: (1) Preparation of precursor mixture Accurately weigh ruthenium source (0.76 mmol, ruthenium trichloride (RuCl3·xH2O)) and manganese source (0.1 mmol, manganese acetate tetrahydrate (Mn(CH3COO)2·4H2O)) as metal sources, and place them together with molten salt (5.0 g sodium nitrate (NaNO3)) in an agate mortar. Then, manually grind for 20 minutes to ensure that all precursor powders are thoroughly and uniformly mixed, thus obtaining the precursor mixture.

[0038] (2) Molten Salt Reaction The precursor mixture obtained in step (1) was transferred to a 50 mL corundum crucible and placed in a box-type muffle furnace. Under static air atmosphere, the furnace temperature was increased from room temperature to 350 °C at a heating rate of 3 °C / min and held at this temperature for 20 minutes to complete the oxidation of ruthenium and the doping of manganese. The reaction products were then allowed to cool naturally to room temperature within the furnace.

[0039] (3) Post-processing of products: Take out the blocky reaction product after cooling in step (2), and clean and dry it.

[0040] Cleaning process: The reaction product is placed in a beaker, and a large amount of deionized water is added. The mixture is then repeatedly washed using a vacuum filtration system and a polyethersulfone organic filter membrane. This process continues until the filtrate is tested with 0.1 mol / L silver nitrate (AgNO3) solution, and no white precipitate is formed. This ensures that any potentially present chloride ions (Cl...) are completely removed. - The ions were completely removed. The polyethersulfone organic filter membrane has a specification of 0.22 μm.

[0041] Drying process: The cleaned wet filter cake was freeze-dried. First, it was deep-frozen at -50℃ for 12 hours, then transferred to a freeze dryer and dried continuously for 24 hours under conditions where the cold trap temperature was below -50℃ and the vacuum pressure in the drying chamber was below 10 Pa. Finally, black manganese-doped ruthenium oxide nanocatalyst powder was obtained, denoted as Ru. 7.6 MnO x .

[0042] Example 2 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture Accurately weigh ruthenium source (0.8 mmol, ruthenium trichloride (RuCl3·xH2O)) and manganese source (0.1 mmol, manganese acetate tetrahydrate (Mn(CH3COO)2·4H2O)) as metal sources.

[0043] Example 3 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture Accurately weigh ruthenium source (0.9 mmol, ruthenium trichloride (RuCl3·xH2O)) and manganese source (0.1 mmol, manganese acetate tetrahydrate (Mn(CH3COO)2·4H2O)) as metal sources.

[0044] Example 4 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture Accurately weigh ruthenium source (0.1 mmol, ruthenium trichloride (RuCl3·xH2O)) and manganese source (0.1 mmol, manganese acetate tetrahydrate (Mn(CH3COO)2·4H2O)) as metal sources.

[0045] Example 5 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture The ruthenium source used is dodecacarbonyltrirutheniumRu3(CO). 12 .

[0046] Example 6 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture The manganese source used is manganese sulfate.

[0047] Example 7 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture The manganese source used is manganese chloride.

[0048] Example 8 This embodiment provides a manganese-doped ruthenium oxide nanocatalyst, which uses the same implementation steps as in Example 1, with the only difference being: (1) Preparation of precursor mixture The manganese source used is manganese nitrate.

[0049] Comparative Example 1 This embodiment provides a catalyst, which uses the same implementation steps as in Embodiment 1, except that: (1) Preparation of precursor mixture Accurately weigh ruthenium source (0.76 mmol, ruthenium trichloride (RuCl3·xH2O)) as the metal source, manganese source is missing.

[0050] The final catalyst powder obtained is denoted as RuO. x .

[0051] Comparative Example 2 This embodiment provides a catalyst, which uses the same implementation steps as in Embodiment 1, except that: (1) Preparation of precursor mixture Accurately weigh out the manganese source (0.1 mmol, manganese acetate tetrahydrate (Mn(CH3COO)2·4H2O)) as the metal source, ruthenium source is missing.

[0052] The final catalyst powder obtained is denoted as MnO. x .

[0053] Test Example 1 Electrochemical tests were conducted in this test case. The acidic oxygen evolution reaction (OER) performance was performed in a standard three-electrode cell (working electrode: sample; reference electrode: Hg / Hg2SO4; counter electrode: graphite rod; electrolyte: 0.5 M H2SO4). Data were recorded using an electrochemical workstation (Modulab XM). Specifically, LSV data (voltage range: 1.0V-0V (relative to the standard Hg / HgSO4 electrode); scan rate: 5 mV·s) were recorded. 1 () is based on the chronoamperometry method at 10 mA·cm -2 It was obtained after activation at a current density of 500 s. Additionally, it was obtained by chronoamperometry at 10 mA·cm⁻¹. -2 Stability data were obtained by testing at a current density.

[0054] The current density is 10 mA·cm -2 The test substance is Ru 7.6 MnO x (Example 1), RuO x (Comparative Example 1) Purchase RuO2 (commercial RuO2, abbreviated as Com.RuO2) and MnO from the market. x (Comparative Example 2), the relevant results are shown in Table 1 and Figure 1 .

[0055] Current density is 100 mA·cm -2 The test material was the manganese-doped ruthenium oxide nanocatalyst prepared in Examples 1-4, and the relevant results are shown in Table 2.

[0056] Table 1 Oxygen Evolution Performance Results

[0057] As can be seen from Table 1, during the OER process, Ru 7.6 MnO x Catalyst at 10 mA·cm -2 At a current density of 208 mV, an overpotential of 208 mV can be achieved, compared to RuO x Com.RuO2 and MnO x Catalyst at 10 mA·cm -2 The overpotentials at current densities are 218mV, 303mV, and 737mV. At higher current densities, Ru... 7.6 MnO x The required voltage is always lower than that of the other catalysts, which indicates that Ru 7.6 MnO x The catalyst is an acidic OER catalyst with excellent performance.

[0058] from Figure 1 It can be seen that Ru 7.6 MnO x The catalyst even exhibits superior oxygen evolution performance compared to RuOx, but Ru 7.6 MnO x It has excellent stability and strong corrosion resistance.

[0059] Table 2 100 mA·cm -2 The current density required for oxygen evolution is the overpotential.

[0060] As can be seen from Table 2, during the OER process, Ru 7.6 MnO x Even with a high current density of 100 mA·cm, the catalyst -2 An overpotential of 413 mV can also be achieved at a current density that is comparable to that of RuO. x Com.RuO2 and MnO x Catalyst at 100 mA·cm -2 The overpotentials at the current densities are 447mV, 556mV, and 1472mV. This indicates that Ru 7.6 MnO x The catalyst is an acidic OER catalyst with excellent performance.

[0061] Test Example 2 This test example focuses on the manganese-doped ruthenium oxide nanocatalyst (Ru) prepared in Example 1. 7.6 MnO x ) and the catalyst (RuO) prepared in Comparative Example 1. x Acid stability tests were performed separately, and the test results are shown in [the table below]. Figure 2 .

[0062] Depend on Figure 2 It can be seen that, in Example 1 (Ru) 7.6 MnO x ) and Comparative Example 1 (RuO x ) at 10mA·cm -2 The operating time at the current density was 2000 hours. However, the manganese-doped ruthenium oxide nanocatalyst in Example 1 showed good stability for acidic OER with a decay rate of 1.4 μV / h, while the decay rate of Comparative Example 1 was 64 μV / h.

[0063] The attenuation rate is defined as the ratio of the change in voltage rise during the stability test to the stability test time.

[0064] Test Example 3 This test example examines manganese-doped ruthenium oxide nanocatalysts prepared with different proportions of Ru and Mn at 50 mA·cm⁻¹. -2 Acid stability tests were conducted at Ru:Mn ratios of 5:1, 6:1, 7:1, 7.6:1, 8:1, and 9:1. The relevant test results are shown below. Figure 3 .

[0065] Depend on Figure 3 It can be seen that only Example 1 (Ru) 7.6 MnO x ) at 50mA·cm -2 It can operate for longer periods at high current densities with the lowest voltage increase, therefore Ru 7.6 MnO x It is a highly stable acidic OER catalyst.

[0066] Test Example 4 This test example focuses on the manganese-doped ruthenium oxide nanocatalyst (Ru) prepared in Example 1. 7.6 MnO x ) and the catalyst (RuO) prepared in Comparative Example 1. x TEM tests and particle size distribution analysis were performed separately. The test results are shown in […]. Figures 4-5 ;in, Figure 4 TEM test results and particle size distribution analysis of the manganese-doped ruthenium oxide nanocatalyst prepared in Example 1; Figure 5 The TEM test results and particle size distribution analysis of the catalyst prepared in Comparative Example 1 are shown.

[0067] Depend on Figure 4 It can be seen that the catalyst Ru 7.6 MnO x It consists of nanoparticles with uniform particle size and shape, and an average particle size of 6.4 nm.

[0068] Depend on Figure 5 It can be seen that the catalyst RuO x It consists of nanoparticles with somewhat uneven particle size and shape, with an average particle size of 8.3 nm.

[0069] Test Example 5 This test example performs XRD tests on the catalysts prepared in Example 1 and Comparative Examples 1-2, respectively. In Example 1, the catalyst is Ru... 7.6 MnO x Catalyst, Comparative Example 1 is RuO x The catalyst and Comparative Example 2 are MnO x Catalyst, test results are shown below Figure 6 .

[0070] Depend on Figure 6 It can be seen that Ru7.6 MnO x The diffraction peaks of the catalyst in the XRD pattern are consistent with those of RuO2, compared to RuO2. x Catalyst, Ru 7.6 MnO x The diffraction peaks of the catalyst shift to higher angles because the Mn element is effectively incorporated into the RuO2 lattice, causing a certain degree of lattice shrinkage.

[0071] In summary, the manganese-doped ruthenium oxide nanocatalyst provided by this invention constructs a stable composite structure by introducing manganese, which significantly improves its structural stability while maintaining high intrinsic activity. Furthermore, it exhibits excellent oxygen evolution overpotential and corrosion resistance, driving water oxidation in acidic electrolytes at a low potential while maintaining good stability, overcoming the poor stability of commercial ruthenium oxide catalysts in acidic media. It demonstrates outstanding electrocatalytic performance in 0.5 mol / L H₂SO₄ electrolyte: the oxygen evolution overpotential is as low as 208 mV (@10 mA·cm⁻¹). -2 It exhibits excellent durability in acidic media, reaching up to 10 mA·cm⁻¹. -2 The catalyst operated stably for 2000 hours. It is well-suited for future large-scale hydrogen production applications and meets the standards for future clean energy applications. The preparation method is a one-pot molten salt synthesis, which is simple and efficient, providing a key material solution for efficient and long-life proton exchange membrane water electrolysis hydrogen production technology.

[0072] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A manganese-doped ruthenium oxide nanocatalyst, characterized in that, The molar ratio of ruthenium to manganese in the catalyst is (5-9):1; the average particle size of the catalyst is 6nm-8nm.

2. The manganese-doped ruthenium oxide nanocatalyst according to claim 1, characterized in that, The molar ratio of ruthenium to manganese in the catalyst is (7-8):

1.

3. The manganese-doped ruthenium oxide nanocatalyst according to claim 1, characterized in that, The ruthenium source is selected from at least one of ruthenium chloride, ruthenium nitrate, ruthenium acetate, carbonyl compounds of ruthenium, and acetylacetone compounds of ruthenium.

4. The manganese-doped ruthenium oxide nanocatalyst according to claim 1, characterized in that, The manganese source of the manganese element is selected from at least one of manganese sulfate, manganese acetate, manganese chloride, manganese nitrate, manganese oxalate, and manganese acetylacetone compounds.

5. A method for preparing manganese-doped ruthenium oxide nanocatalyst as described in any one of claims 1-4, characterized in that, Includes the following steps: Ruthenium source, manganese source and molten salt are mixed in proportion to obtain precursor mixture; The precursor mixture was heated to 340°C-360°C in air at a heating rate of 1°C / min-5°C / min to carry out a molten salt reaction. The reaction product was post-processed to obtain manganese-doped ruthenium oxide nanocatalyst.

6. The preparation method according to claim 5, characterized in that, The molten salt is selected from at least one of alkali metal nitrates and alkali metal carbonates.

7. The preparation method according to claim 5, characterized in that, The temperature of the molten salt reaction is 320℃-360℃, and the time is 15min-25min; Preferably, the temperature of the molten salt reaction is 350℃-360℃, and the time is 20min-25min.

8. The preparation method according to claim 5, characterized in that, The post-processing includes: naturally cooling the reaction product to room temperature, washing with water to remove molten salt, and freeze-drying.

9. An electrode, characterized in that, The catalytic active layer of the electrode comprises the manganese-doped ruthenium oxide nanocatalyst as described in any one of claims 1-4 or the manganese-doped ruthenium oxide nanocatalyst prepared by the preparation method as described in any one of claims 5-8.

10. A device for producing hydrogen through water electrolysis, characterized in that, The anode of the water electrolysis hydrogen production device includes the electrode as described in claim 9.

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