Preparation method of high-gold-attribute entropy-based oxide catalyst and application thereof in hydrogen production by acidic electrolysis of water

Abstract

The application relates to a preparation method of an entropy-based oxide catalyst with high metallic property and application of the entropy-based oxide catalyst in hydrogen production by acidic electrolytic water, and belongs to the field of catalysis. A water-soluble salt containing at least Ru, Ir and A is uniformly mixed, hydrolyzed and reduced under water bath stirring condition by taking zinc oxide as a carrier and a sodium borohydride solution as a reducing agent, then the black powder of the medium-entropy alloy is formed through filtration, washing and drying, and finally the black powder is subjected to rapid incomplete oxidation under the condition of 300-500 DEG C and air atmosphere, and then is subjected to acid pickling, filtration, washing and drying to prepare the entropy-based oxide catalyst with high metallic property. The catalyst contains a large amount of Ir-Ir metal bonds and / or Ir-Ru metal bonds, and the proportion can reach 30%-40%. The mismatch between the metal atom fingerprint structure and the metal-oxygen atom coordination structure causes serious lattice distortion, induces unbalanced distribution of stress and strain, and promotes the kinetics of the acidic oxygen evolution reaction.

Description

Technical Field

[0001] This invention belongs to the field of energy materials technology for hydrogen production by acidic water electrolysis, specifically relating to a method for synthesizing a highly conductive metallic entropy-based oxide catalyst and its application as a highly efficient oxygen evolution catalyst in the field of hydrogen production by acidic water electrolysis. Background Technology

[0002] With the continuous growth of global energy demand and the increasing severity of environmental problems, the search for renewable energy has become an important issue for society today. Among many renewable energy technologies, hydrogen energy has attracted much attention due to its advantages such as cleanliness, high efficiency, and high energy density. Water electrolysis to produce green hydrogen is an important hydrogen production method, in which the oxygen evolution reaction (OER) is a key step. However, due to the slow kinetics of OER, a highly efficient catalyst is needed to accelerate the reaction rate. Currently, ruthenium (Ru) or iridium (Ir)-based oxides are the most suitable catalysts for OER, especially medium-to-high entropy oxides based on Ru or Ir components (entropy-based oxides). Due to their unique structural characteristics and physicochemical properties, such as the component cocktail effect and lattice distortion effect, these oxides possess high electrocatalytic performance, but their poor conductivity severely limits their application. To solve these common problems, this invention proposes a strategy of controlled thermal oxidation of RuIr-based alloys to optimize the structure and properties of the oxidation products and prepare highly conductive entropy-based oxides. During the oxidation of Ru or Ir components, Ru can be oxidized to RuO2 at a relatively low temperature (approximately 300℃), requiring relatively low energy. In contrast, the oxidation of Ir is more complex, requiring higher temperatures (approximately 800℃) and energy to form IrO2. The Ir(100) and Ir(111) crystal planes are relatively easy to oxidize, while the Ir(110) crystal plane exhibits higher oxidation resistance due to its unique atomic arrangement and high surface energy. Therefore, the oxidation-resistant Ir crystal plane is retained during the oxidation process. Thus, by utilizing the difference in oxidation capabilities between the two metals and controlling the oxidation temperature, metallic RuIr-based oxides that retain some metallic bonds can be obtained, enabling the preparation of novel acidic water electrolysis catalysts. Metallic entropy-based oxides combine the properties of metals and oxides, exhibiting high metallicity, high lattice distortion, and high conductivity. This structural inhomogeneity can modulate the band structure, generating more active sites and contributing to improved catalytic performance. Furthermore, conductivity directly affects electrocatalytic activity. Highly conductive materials can transport electrons more rapidly, reducing charge accumulation and resistance loss, and maintain stable performance under high current density and long-term operation to prevent structural changes or degradation that could lead to catalyst deactivation. Therefore, entropy-based metallic oxides, as a new generation of high-performance water electrolysis catalysts, are of great significance for promoting the large-scale commercial application of acidic water electrolysis for hydrogen production. Summary of the Invention

[0003] The purpose of this invention is to provide a method for preparing a highly metallic entropy oxide catalyst containing numerous metal bonds with high electrocatalytic activity and stability, and its application in acidic water electrolysis for hydrogen production. Preferably, the highly metallic entropy oxide catalyst containing Ir-Ru / Ir metal bonds is RuIrAO2, where A = one or more of Mn and Co. RuIrAO2 is RuIrMnO2 or RuIrCoO2. The highly metallic entropy oxide catalyst may also include other metal elements such as Y and Cr, corresponding to highly metallic entropy oxide catalysts like RuIrMnYO2. The proportion of metal bonds in the highly metallic entropy oxide catalyst can reach 30%-40%. The catalyst possesses a large number of atomically ordered short-range metallic atomic networks, and the conductivity of the highly metallic entropy oxide reaches 1.92 × 10⁻⁶. -7 With a conductivity of Ω·m, close to that of graphite or metals, it can be used in acidic water electrolysis for hydrogen production. In the anodic oxygen evolution reaction under acidic conditions, 10 mA cm⁻¹ -2 It exhibits an ultra-low overpotential of 212 mV at a low current density, far lower than the 277 mV of commercial IrO2 catalysts. For PEMWE devices, the metallic entropy-based oxide catalyst RuIrMnO2 can achieve an overpotential of 50 mA cm⁻¹. -2 It operates for 170 hours at a low and unchangeable battery potential (1.69V), which far exceeds that of commercial IrO2||Pt / C modules (20 hours).

[0004] This invention relates to a method for preparing an entropy-based oxide catalyst with high metallicity and its application in the field of acidic water electrolysis. First, using zinc oxide as a support and sodium borohydride (NaBH4) solution as a reducing agent, multiple water-soluble metal salts containing at least Ru, Ir, and A are mixed uniformly and subjected to hydrolysis and reduction under water bath stirring conditions. Subsequently, after filtration, washing, and drying, a medium-entropy alloy black powder is formed. Finally, rapid incomplete oxidation is carried out in an air atmosphere at 300-500℃, preferably 350℃, followed by acid washing, filtration, washing, and drying, thus preparing an entropy-based oxide catalyst with high metallicity for the first time. The high-metallicity entropy-based oxide catalyst contains a large number of Ir-Ir metallic bonds and / or Ir-Ru metallic bonds, accounting for 30%-40%, and has a large number of atomically ordered short-range metallic atomic network structures. The entropy-based oxide catalyst is a crystalline nanoparticle with a stable rutile configuration oxide nanoparticle with a particle size of approximately 3-9 nm.

[0005] This invention also protects a method for preparing the highly metallic entropy-based alloy catalyst, comprising the following steps:

[0006] (1) Disperse zinc oxide carrier in deionized water and form a uniform milky white slurry by ultrasonic treatment;

[0007] (2) Dissolve at least a Ru source solution, an Ir source solution and an A source solution precursor in the above slurry and sonicate to obtain a homogeneous metal salt mixed solution.

[0008] (3) Under stirring conditions in a water bath (e.g., 40-80℃, preferably 60℃), the NaBH4 reducing agent solution is added dropwise to the above metal salt mixed solution to induce the precipitation of the metal salt; then, the solid obtained by vacuum filtration is washed with deionized water to remove residual impurities and dried in an oven at 60-80℃ to obtain uniformly dispersed ruthenium-iridium-manganese alloy nanoparticles with distinct particle sizes.

[0009] (4) Preparation of high metallic entropy-based oxide powder containing a large number of metal bonds: The ruthenium-iridium-manganese entropy-based alloy particles dried in step (3) are placed in a tube furnace for rapid incomplete oxidation transformation, that is, heated to a certain temperature at a certain heating rate in a certain atmosphere, held for a certain time, and then naturally cooled to room temperature with the tube furnace; subsequently, acid washing is performed in a sulfuric acid solution of a certain concentration, and the powder is filtered, washed, and dried to obtain high metallic entropy-based oxide catalyst powder with a large number of Ir-Ir or / and Ir-Ru metal bonds.

[0010] In a preferred embodiment of the present invention, the size of nanoparticles can be controlled by adjusting the ratio of the amount of metal salt precursor to the zinc oxide carrier. Generally, 20 mg of zinc oxide corresponds to 0.05-0.5 mmol of total metal salt molar amount. At the same time, by precisely controlling the dropping rate of the NaBH4 reducing agent solution, the uniform distribution of alloy nanoparticles can be ensured.

[0011] In a preferred embodiment of the present invention, the Ru source, Ir source, and A source in the precursor solution are anions of soluble Ru salt, soluble Ir salt, and soluble A salt, selected from one or more of acetate ion, chloride ion, and sulfate ion.

[0012] In a preferred embodiment of the present invention, the Ru source, Ir source, and A source are ruthenium trichloride, chloroiridic acid, and manganese chloride or cobalt chloride, with the following molar percentages of metal elements: Ru: 35%-45 at%; Ir: 25%-35 at%; A: 25%-35 at%, and the molar ratio of ruthenium trichloride, chloroiridic acid, and the chloride of A is 6:4:(2-6). Each 20 mg of zinc oxide carrier corresponds to 20-30 ml of deionized water.

[0013] In a preferred embodiment of the present invention, the sodium borohydride reduction reaction temperature in step (3), i.e., the water bath temperature, is 55-80°C, preferably 60°C.

[0014] In a preferred embodiment of the present invention, the amount of sodium borohydride used in step (3) is 5-10 times the total amount of metal elements fed in.

[0015] In a preferred embodiment of the present invention, the rapid incomplete oxidation transition temperature in step (3) is 300-500°C, preferably 350°C.

[0016] In a preferred embodiment of the present invention, the rapid incomplete oxidation heating rate in step (4) is 5-10℃ / min, preferably 5℃ / min.

[0017] In a preferred embodiment of the present invention, in step (4), the atmosphere for the rapid incomplete oxidation transformation is air.

[0018] In a preferred embodiment of the present invention, in step (4), the holding time for the rapid incomplete oxidation transformation is 0.5-1.5h, preferably 1h.

[0019] In a preferred embodiment of the present invention, in step (4), the pickling concentration is 0.5-2M H. + The preferred proton concentration is 1 M.

[0020] In a preferred embodiment of the present invention, in step (4), the liquid used for pickling can be sulfuric acid, hydrochloric acid, nitric acid, etc., with sulfuric acid being preferred.

[0021] In a preferred embodiment of the present invention, in step (4), the pickling time is 0.5-1.5h, preferably 1h.

[0022] In further step (2), the precursors added are Ru source, Ir source and A source, which correspond to the metallic entropy-based oxide catalyst RuIrAO2; the precursors in step (2) may also include other metal element B source substances, which correspond to the metallic entropy-based oxide catalyst RuIrABO2. Other metal elements B are selected from Y, Cr, etc., and the corresponding other metal element B source substances are B sulfate, chloride, etc.; the molar ratio of B to A is 0-2:1, which is further preferred to be 0-1:1.

[0023] The application of the high-metallicity entropy-based oxide catalyst obtained in this invention in acidic water electrolysis for hydrogen production. The mismatch between the metal bonds and oxide structure in the high-metallicity entropy-based oxide catalyst leads to severe lattice distortion, inducing an imbalanced stress-strain distribution and promoting the kinetics of the acidic oxygen evolution reaction. The catalyst exhibits high conductivity, possessing a large number of atomically ordered short-range metallic atomic networks, with a resistivity of 1.92 × 10⁻⁶. -7 Ω·m, close to the conductivity of graphite or metals.

[0024] This invention breaks the common seesaw relationship between activity and stability in acidic OER water cracking by controlling the relative content of metal bonds in high metal entropy-based oxide catalysts. This technical solution is simple and controllable, opening a door to the design and development of advanced catalysts, providing feasibility for large-scale industrial applications, and demonstrating its broad prospects and economic value in practical applications.

[0025] The Ir-Ir / Ru metallic bonds and their short-range ordered metallic atomic network structure in the high metallicity entropy-based oxides prepared in this invention activate the asymmetric metal-oxidation chemical bonds, promoting the kinetics of acidic oxygen evolution reaction. Simultaneously, the presence of a certain degree of metallic bonding enhances the catalyst's conductivity, facilitating electron transfer and participation in the chemical reaction, further improving its activity. Furthermore, the short-range ordered metallic atomic network structure slows down the dissolution process of Ru and Ir, inhibits the release of lattice oxygen, and mitigates electrochemical corrosion, thus ensuring long-term stability. The formation enthalpy and binding energy of the corresponding oxides are further reduced, guaranteeing the structural stability of the metal-oxygen and metal-metal chemical bonds and achieving catalyst durability.

[0026] This invention employs a two-step synthesis method, which is easy to operate, highly practical, and capable of large-scale production. The resulting entropy-based oxides, such as RuIrMnO2, containing Ir-Ir / Ru metallic bonds and a metallic atomic network structure, can be applied to the field of efficient acidic water electrolysis for hydrogen production. They exhibit superior electrocatalytic activity compared to commercial iridium dioxide and demonstrate higher stability under high current density conditions. Compared to existing water electrolysis catalysts, the entropy-based oxide catalyst with high metallicity shows better electrocatalytic activity in the anodic oxygen evolution reaction under acidic environments at 10 mA cm⁻¹. -2 It exhibits an ultra-low overpotential of 212 mV at a low current density, far lower than the 277 mV of commercial IrO2 catalysts; for PEMWE devices, metallic entropy-based oxide catalysts such as RuIrMnO2 can achieve an overpotential of 50 mA cm⁻¹. -2 It operates for 170 hours at a low and unchangeable battery potential (1.69V), which far exceeds that of commercial IrO2||Pt / C modules (20 hours). Attached Figure Description

[0027] The present invention will be further described below with reference to the accompanying drawings. The drawings are only for illustrative purposes and do not limit the scope of the present invention.

[0028] Figure 1 These are transmission electron microscope (TEM) images and particle size distribution diagrams of the ruthenium-iridium-manganese alloy nanoparticles obtained in Example 1.

[0029] Figure 2 This is a transmission electron microscope (TEM) image of the entropy-based ruthenium-iridium-manganese oxide with high metallicity obtained in Example 1.

[0030] Figure 3 The X-ray diffraction (XRD) patterns of the ruthenium-iridium-manganese alloy and the ruthenium-iridium-manganese oxide catalyst with high metallicity entropy in Example 1 are shown.

[0031] Figure 4 The high-resolution XPS spectra of Ru 3p and Ir 4f in the ruthenium-iridium-manganese alloy and the ruthenium-iridium-manganese oxide catalyst with high metallicity in Example 1 are shown.

[0032] Figure 5 The polarization curves of the high metallicity entropy-based oxide catalysts prepared in Examples 1, 2, and 3, and commercial IrO2, are shown at 10 mA cm⁻¹. -2 50mA cm -2 and 100mA cm -2 The overpotential histogram is shown at the specified current density. The electrolyte used in the test was 0.5 M H₂SO₄; the scan rate was 10 mV / s. -1 The scanning voltage range is 0.525-0.9V.

[0033] Figure 6 These are the X-ray diffraction (XRD) patterns of the RuIrMnO2 catalyst with high property entropy in Example 1 before and after constant current testing.

[0034] Figure 7 The chronopotential curve (current density 50 mA cm⁻¹) of a PEMWE cell assembled with the catalyst obtained in Example 1 and commercial IrO₂ as the anode catalyst and commercial Pt / C (40 wt% Pt) as the cathode catalyst in 0.5 M H₂SO₄ is shown. -2 ).

[0035] Figure 8 This describes the valence state distribution of Ru and Ir in the high-property-entropy RuIrMnO2 catalyst of Example 1, where Ru... 0 32.4%, Ir 0 The proportion of 44.7% indicates that some metals exist in a zero-valence state, which is an Ir-Ir / Ru bond. Detailed Implementation

[0036] The following detailed description is based on specific embodiments, but the scope of protection of the present invention is not limited to the specific implementation methods.

[0037] Example 1:

[0038] High metallicity entropy-based RuIrMnO2 catalyst

[0039] (1) 20 mg of zinc oxide was ultrasonically dispersed in 20 mL of aqueous solution to form a milky white slurry. 0.75 mL of 0.1 M LuCl3, 0.5 mL of 0.1 M H2IrCl6 and 0.5 mL of 0.1 M MnCl2 metal salt solution were dissolved in the above slurry and ultrasonicated for 30 min.

[0040] (2) 35 mg NaBH4 was completely dissolved in 10 mL of deionized water and then gradually added dropwise to the mixed solution in step (1) over 30 min under stirring at 60 °C. A precipitate was formed. The obtained solid powder was separated from the solution by a vacuum filter and rinsed with a large amount of deionized water to remove the residue. The powder was then dried in an oven at 60 °C for 12 h.

[0041] (3) Place the dried sample from step 2 into a porcelain boat and heat it in air at 5°C for 5 minutes. -1 The temperature was increased to 350℃ and held for 1 hour. After cooling, the mixture was acidified in 0.5M H2SO4 solution for 1 hour. Finally, it was filtered, washed, and dried to obtain the high-metallicity entropy-based oxide RuIrMnO2 catalyst prepared by rapid incomplete thermal oxidation. For the oxides obtained by rapid incomplete oxidation transformation, the valence state distribution in the high-metallicity entropy-based oxides can be obtained by X-ray photoelectron spectroscopy (XPS) of typical ruthenium-iridium-manganese oxides and then processing the data using Avantage software.

[0042] Example 2

[0043] High metallicity entropy-based RuIrCoO2 catalyst

[0044] (1) 20 mg of zinc oxide was ultrasonically dispersed in 20 mL of aqueous solution to form a milky white slurry. 0.75 mL of 0.1 M LuCl3, 0.5 mL of 0.1 M H2IrCl6 and 0.5 mL of 0.1 M CoCl2 metal salt solution were dissolved in the above slurry and ultrasonicated for 30 min.

[0045] (2) 35 mg NaBH4 was completely dissolved in 10 mL of deionized water and then gradually added dropwise to the mixed solution in step (1) over 30 min under stirring at 60 °C. A precipitate was formed. The obtained solid powder was separated from the solution by a vacuum filter and rinsed with a large amount of deionized water to remove the residue. The powder was then dried in an oven at 60 °C for 12 h.

[0046] (3) Place the dried sample from step 2 into a porcelain boat and heat it in air at 5°C for 5 minutes. -1The heating rate was increased to 350℃, held for 1 hour, cooled, and then acidified in 0.5M H2SO4 solution for 1 hour. Finally, the catalyst was filtered, washed, and dried to obtain the high metallic entropy-based oxide RuIrCoO2 catalyst prepared by rapid incomplete thermal oxidation.

[0047] Example 3

[0048] High metallicity entropy-based RuIrMnYO2 catalyst

[0049] (1) 20 mg of zinc oxide was ultrasonically dispersed in 20 mL of aqueous solution to form a milky white slurry. 0.75 mL of 0.1 M RuCl3, 0.5 mL of 0.1 M H2IrCl6, 0.5 mL of 0.1 M MnCl2 and 0.5 mL of 0.05 M Y2(SO4)3 metal salt solution were dissolved in the above slurry and ultrasonicated for 30 min.

[0050] (2) 35 mg NaBH4 was completely dissolved in 10 mL of deionized water and then gradually added dropwise to the mixed solution in step (1) over 30 min under stirring at 60 °C. A precipitate was formed. The obtained solid powder was separated from the solution by a vacuum filter and rinsed with a large amount of deionized water to remove the residue. The powder was then dried in an oven at 60 °C for 12 h.

[0051] (3) Place the dried sample from step 2 into a porcelain boat and heat it in air at 5°C for 5 minutes. -1 The heating rate was increased to 350℃, held for 1 hour, cooled, and then acidified in 0.5M H2SO4 solution for 1 hour. Finally, the catalyst was filtered, washed, and dried to obtain the high metallic entropy-based oxide RuIrMnYO2 catalyst prepared by rapid incomplete thermal oxidation.

[0052] Figure 1 This is a transmission electron microscope (TEM) image of the ruthenium-iridium-manganese alloy nanoparticles obtained in Example 1. The average particle size of the alloy nanoparticles is 2.66 nm, the alloy is uniformly distributed, and the particle size is controllable.

[0053] Figure 2 This is a transmission electron microscope (TEM) image of the metallic entropy-based ruthenium-iridium-manganese oxide catalyst obtained in Example 1. The average particle size of the oxide nanoparticles is 7 nm.

[0054] Figure 3 The X-ray diffraction (XRD) pattern of the catalyst obtained in Example 1 shows that the peak positions are close to those of rutile ruthenium dioxide, indicating that the prepared catalyst has a typical rutile structure.

[0055] Figure 4These are high-resolution XPS spectra of Ru 3p and Ir 4f in the ruthenium-iridium-manganese alloy and the partially metallic ruthenium-iridium-manganese oxide catalyst from Example 1. It can be seen that the proportion of metallic bonds is 30%-40%, indicating that the prepared oxide catalyst has metallic characteristics.

[0056] Figure 5 The polarization curves of the metallic entropy-based oxide catalysts prepared in Examples 1, 2, and 3 and commercial IrO2 are shown at 10 mA cm⁻¹. -2 50mA cm -2 and 100mA cm -2 The overpotential histogram is shown at the specified current density. The electrolyte used in the test was 0.5 M H₂SO₄; the scan rate was 10 mV / s. -1 The scanning voltage range was 0.525–0.9 V. It can be observed that the rapidly oxidized metallic entropy-based oxide catalysts containing metallic bonds exhibited high performance at 10 mA cm⁻¹. -2 The overpotentials at the current densities were 212mV, 216mV, and 244mV, respectively, which are far lower than the 277mV of commercial IrO2. Furthermore, they exhibited even lower overpotentials at higher current densities.

[0057] Figure 6 These are the X-ray diffraction (XRD) patterns of the RuIrMnO2 catalyst in Example 1 before and after galvanostatic testing. It can be observed that there is no significant change in crystallinity before and after the electrochemical test; the catalyst remains a stable rutile structure.

[0058] Figure 7 The chronopotential curve (current density 50 mA cm⁻¹) of a PEMWE cell assembled with the catalyst obtained in Example 1 and commercial IrO₂ as the anode catalyst and commercial Pt / C (40 wt% Pt) as the cathode catalyst in 0.5 M H₂SO₄ is shown. -2 After 170 hours of chronopotential testing, the overpotential rise of the prepared catalyst was negligible, demonstrating excellent durability, especially for a commercially available iridium dioxide (IrO2) catalyst.

[0059] Figure 8 This describes the valence state distribution of Ru and Ir in the high-property-entropy RuIrMnO2 catalyst of Example 1, where Ru... 0 32.4%, Ir 0 The proportion of 44.7% indicates that some metals exist in a zero-valence state, which is an Ir-Ir / Ru bond.

[0060] The abundant Ir-Ir / Ru metallic bonds and the atomically short-range ordered network structure of metallic atoms activate the asymmetric metal-oxidation bonds, promoting the kinetics of acidic oxygen evolution reaction. Furthermore, the enhanced conductivity of the high-metallicity entropy-based oxide facilitates electron transfer and participation in the chemical reaction, further improving its activity. More importantly, the metallic bond interactions suppress the release of lattice oxygen, slowing down the dissolution process of Ru and Ir, thus ensuring long-term stability. The preferred high-metallicity entropy-based RuIrMnO2 catalyst, in 0.5 M H₂SO₄ medium, exhibits good conductivity at 10 mA cm⁻¹. -2 At the specified current density, the overpotential for oxygen evolution is 212 mV, significantly lower than the 277 mV of commercial IrO2 catalysts. For PEMWE devices, the RuIrMnO2 catalyst can achieve a current density of 50 mA cm⁻¹. -2 The catalyst operated for 170 hours at a low battery potential (1.69V), significantly exceeding the performance of commercial IrO2||Pt / C modules (20 hours). This demonstrates that this technique, by controlling the relative content of metal bonds in the entropy-based oxide catalyst, can substantially improve the activity and stability of the water electrolysis catalyst. The technique is simple, its synthesis is straightforward and controllable, opening a door to the design and development of advanced catalysts and providing feasibility for large-scale industrial applications, showcasing its broad prospects and economic value in practical applications.

[0061] The above detailed embodiments describe the basic principles and main features of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments, and any changes or modifications conceived without creative effort should be covered within the scope of protection of the present invention. Various changes and modifications can be made to the present invention without departing from its scope, and all such changes and modifications will fall within the scope of protection claimed.

Claims

1. The application of a highly metallic entropy-based oxide catalyst in acidic water electrolysis for hydrogen production, characterized in that, The catalyst preparation method includes the following steps: First, using zinc oxide as a support and NaBH4 solution as a reducing agent, under water bath stirring conditions, a homogeneous mixture of multiple water-soluble metal salts containing at least Ru, Ir, and A is added and hydrolyzed and reduced. Then, after filtration, washing, and drying, a medium-entropy alloy black powder is formed. Finally, rapid incomplete oxidation is performed in air at 350°C, followed by acid washing, filtration, washing, and drying, thus preparing a high-metallicity entropy-based oxide catalyst for the first time. The high-metallicity entropy-based oxide catalyst contains a large number of Ir-Ir metallic bonds and / or Ir-Ru metallic bonds. The catalyst contains a large number of atomically ordered short-range metallic atomic network structures. The mismatch between the metallic atomic network structure and the metal-oxygen atom coordination structure leads to severe lattice distortion. The conductivity of the high-metallicity entropy-based oxide reaches 1.92 × 10⁻⁶. -7 Ω·m; A is manganese or cobalt; The pickling process uses sulfuric acid, hydrochloric acid, or nitric acid as the liquid. The catalyst contains a large number of Ir-Ir metallic bonds and / or Ir-Ru metallic bonds, accounting for 30%-40%, and has a large number of atomically ordered short-range metallic atomic network structures. The entropy-based oxide catalyst is a crystalline nanoparticle with a stable rutile configuration oxide nanoparticle with a particle size of 3-9 nm.

2. The application according to claim 1, characterized in that, The preparation method of the catalyst specifically includes the following steps: (1) Disperse the zinc oxide carrier in deionized water and form a uniform milky white slurry by ultrasonic treatment; (2) Dissolve at least the Ru source solution, Ir source solution and A source solution precursor in the above slurry and sonicate to obtain a uniform metal salt mixed solution; (3) Under water bath stirring conditions, the NaBH4 reducing agent solution was added dropwise to the above metal salt mixed solution to induce the precipitation of metal salt; Subsequently, the solid obtained by vacuum filtration was washed with deionized water to remove residual impurities and dried to obtain uniformly dispersed alloy nanoparticles with distinct particle sizes. (4) Preparation of high metal entropy-based oxide powder containing a large number of metal bonds: The alloy nanoparticles dried in step (3) are placed in a tube furnace for rapid incomplete oxidation transformation, that is, heated to a certain temperature at a certain heating rate in a certain atmosphere, held for a certain time, and then naturally cooled to room temperature with the tube furnace; then acid washed in a sulfuric acid solution of a certain concentration, and filtered, washed and dried to obtain high metal entropy-based oxide catalyst powder with a large number of Ir-Ir or / and Ir-Ru metal bonds.

3. The application according to any one of claims 1-2, characterized in that, Each 20 mg of zinc oxide corresponds to 0.05-0.5 mmol of total metal salt molar amount; at the same time, by precisely controlling the dropping rate of the NaBH4 reducing agent solution, the uniform distribution of alloy nanoparticles is ensured.

4. The application according to any one of claims 1-2, characterized in that, The Ru source, Ir source, and A source in the precursor solution are anions of soluble Ru salt, soluble Ir salt, and soluble A salt, selected from one or more of acetate ion, chloride ion, and sulfate ion; Ru, calculated based on the molar percentage of metallic elements, is 35%-45 at%; Ir: 25%-35 at%; A: 25%-35 at%; Each 20 mg of zinc oxide carrier corresponds to 20-30 ml of deionized water.

5. The application according to claim 4, characterized in that, The Ru source, Ir source, and A source are ruthenium trichloride, chloroiridic acid, and manganese chloride or cobalt chloride, with the molar ratio of ruthenium trichloride, chloroiridic acid, and the chloride of A being 6:4:(2-6).

6. The application according to any one of claims 1-2, characterized in that, The NaBH4 reduction reaction temperature, i.e., the water bath temperature, is 55-80 ℃; the amount of NaBH4 moles used is 5-10 times the total amount of metal elements added.

7. The application according to claim 6, characterized in that, The NaBH4 reduction reaction temperature, i.e., the water bath temperature, is 60 ℃.

8. The application according to any one of claims 1-2, characterized in that, The rapid incomplete oxidation heating rate is 5-10 ℃ / min; The holding time for the rapid incomplete oxidation transformation is 0.5-1.5 h; The pickling concentration is 0.5-2 M H₂ + Proton concentration 1 M; Sulfuric acid was used for pickling; The pickling time is 0.5-1.5 h.

9. The application according to claim 8, characterized in that, The holding time for the rapid incomplete oxidation transformation is 1 hour; The pickling concentration is 1 M H + Proton concentration; The pickling time is 1 hour.

10. The application according to any one of claims 1-2, characterized in that, If the added precursors are Ru source, Ir source and A source, then the corresponding metallic entropy-based oxide catalyst RuIrAO2 is obtained; the precursor in step (2) also includes other metal element B source substances, and the corresponding metallic entropy-based oxide catalyst RuIrABO2 is obtained. Other metal element B is selected from Y and Cr, and the corresponding other metal element B source substances are B sulfate and chloride; the molar ratio of B to A is 0-2:1 and is not 0.

11. The application according to any one of claims 1-2, characterized in that, The molar ratio of B to A is 0-1:1, and is not 0.

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