Preparation method of electrode catalyst

Abstract

The invention provides a preparation method of an electrode catalyst. The preparation method comprises the following steps: preparing a metal precursor solution; adding a morphology inducer into the metal precursor solution; under an alkaline condition, carrying out heat preservation and stirring at a preset temperature for a preset time to obtain an intermediate; the intermediate is subjected to pore forming treatment, the electrode catalyst is obtained, the electrode catalyst comprises a coralline-shaped dealloyed nanowire array structure, and the nanowire array structure is of a coralline-shaped porous structure. According to the electrode catalyst and the preparation method and application thereof, electrode catalysts of different structures are obtained, the specific surface area of the electrode catalyst is increased, and active sites are increased, so that the catalytic efficiency is improved, and the production cost is reduced.

Description

Technical Field

[0001] This application relates to the field of electrochemical technology, specifically to a method for preparing an electrode catalyst. Background Technology

[0002] With the increasing consumption of fossil fuels and the resulting environmental problems, people are paying more and more attention to the development and utilization of sustainable and renewable clean energy. Hydrogen energy, due to its environmental friendliness, high energy density, zero carbon emissions, and recyclability, is considered a very promising clean energy source. Currently, there are many ways to produce hydrogen, including water electrolysis, coal gasification, and catalytic conversion of heavy oil and natural gas into hydrogen via steam. Among these, the most practical and cleanest method is electrolysis.

[0003] However, current hydrogen production technology still suffers from problems such as low electrolysis efficiency and high cost, which limit its development. Summary of the Invention

[0004] This application proposes an electrode catalyst, its preparation method, and its application, which can increase the specific surface area of ​​the electrode catalyst, increase the exposure of active sites, improve catalytic efficiency, reduce the amount of precious metals used in the catalyst layer, and significantly reduce costs.

[0005] To solve the above-mentioned technical problems, this application is implemented through the following technical solution.

[0006] This application provides a method for preparing an electrode catalyst, comprising:

[0007] Preparation of metal precursor solutions.

[0008] A morphology inducer is added to the metal precursor solution.

[0009] Under alkaline conditions, the intermediate is obtained by maintaining the temperature and stirring at a preset time for a preset period of time.

[0010] The intermediate is subjected to a pore-forming treatment to obtain the electrode catalyst, which comprises a coral-like dealloyed nanowire array structure having a coral-like porous structure.

[0011] In one embodiment of this application, the length of the nanowire array is 10 μm to 1100 μm, and the diameter of the nanowires is 120 nm to 200 nm.

[0012] In one embodiment of this application, the metal precursor solution contains at least two of the following metal elements: transition metal elements, lanthanide rare earth elements, and platinum group noble metal elements. The transition metal elements include at least one of Mn, Cr, Zr, Fe, Co, Ni, Cu, Zn, Mo, or W. The platinum group noble metal elements include at least one of Ru, Rh, Pd, Ag, Os, Ir, Pt, and Au. The solvent of the metal precursor solution includes pure water, ultrapure water, deionized water, or tap water. The metal elements are derived from water-soluble metal salts such as metal salts, metal halides, metal sulfates, or metal nitrates. Metal salts are acid radicals containing metal elements.

[0013] In one embodiment of this application, the nanowire array structure has the structural formula MN, wherein M is selected from at least one of Mn, Cr, Fe, Co, Ni or Cu, and N is selected from Ir.

[0014] In one embodiment of this application, a first inducing agent and a second inducing agent are added sequentially. The first inducing agent includes solvents such as metal salts, metal halides, metal sulfates, and metal nitrates. The metal is selected from at least two of Mn, Cr, Fe, Co, Ni, Cu, Zn, and platinum group noble metals. The second inducing agent is selected from at least one of organic solvents such as methanol, ethanol, propanol, acetone, dimethylformamide, cyclohexane, ethyl acetate, and dimethyl sulfoxide.

[0015] In one embodiment of this application, the concentration of metal ions in the first inducer is 0.5M, and the molar ratio of the metal precursor solution, the first inducer, and the second inducer is, for example, 1:1.

[0016] In one embodiment of this application, the method further includes adding an organic inducing agent, such as an isophthalic acid ester, phthalate, 1,4-diazabicyclo[2.2.2]octane, triethylenediamine, 1,4-dimethylpiperazine, hexamethylenetetramine, pyromellitic acid, pyromellitic tricarboxylic acid, 1,4-bis(1H-pyrazol-4-yl)benzene, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetracarboxylic acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine, tris(2,4,6)-pyridyl-1,3,5-triazine, etc. At least one of the following: (isobutylaminoethyl)amine, bis(3,5-dicarboxyphenyl)azo, biphenylcarboxylic acid, 2,5-dihydroxyterephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-phenylene diacetic acid, 1,1,2,2-tetra(4-carboxyphenyl)ethylene, 1,3,5-tris(4-carboxyphenyl)benzene, 2-(diphenylphosphino)terephthalic acid, 2-amino-4-hydroxy-6-methylpyrimidine, 2-methylimidazolium, 2-aminoterephthalic acid, terephthalic acid, fumaric acid, and trioctyl trimellitate.

[0017] In one embodiment of this application, the molar ratio of the organic inducer to the total metal ion concentration in the metal precursor solution is, for example, 1:10000 to 100:1.

[0018] In one embodiment of this application, alkaline substances such as ammonia and potassium hydroxide are added to a mixed solution of a metal precursor solution and a morphology inducer, the pH value is controlled at 8-14, and the mixture is kept warm and stirred to obtain solid intermediates with different morphologies.

[0019] In one embodiment of this application, the intermediate is cleaned and filtered to remove impurities. When creating pores in the intermediate, acid washing or calcination is used to remove some metals and form pores on the catalyst surface to obtain a porous electrode catalyst.

[0020] In summary, this application proposes an electrode catalyst, its preparation method, and its application. This catalyst increases the specific surface area of ​​the electrode catalyst, thereby increasing the contact area with water and improving catalytic efficiency for the same mass. By using the electrode catalyst to form a membrane electrode, the amount of precious metals in the catalyst layer can be reduced, significantly lowering costs, while maintaining high catalytic performance. The regular shape and uniform size of the electrode catalyst facilitate fluid transport, improving mass transfer efficiency and intensity, and enhancing catalytic performance. Furthermore, the reactants and reaction conditions can be controlled to obtain an electrode catalyst with the desired morphology. Attached Figure Description

[0021] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0022] Figure 1 The image shown is a scanning electron microscope (SEM) image of the electrode catalyst in one embodiment of this application.

[0023] Figure 2 The image shown is a scanning electron microscope image of the electrode catalyst in another embodiment of this application.

[0024] Figure 3 The image shown is a scanning electron microscope image of the electrode catalyst in another embodiment of this application.

[0025] Figure 4 Display as Figure 1 The image shows a physical picture and performance curve of the membrane electrode prepared by the electrode catalyst shown.

[0026] Figure 5 This is a structural diagram of the electrodes of an electrolytic cell in one embodiment of this application.

[0027] Figure 6 This is a schematic diagram of an electrode observed with a magnification of 10,000x using a scanning electron microscope in one embodiment of this application.

[0028] Figure 7 This is a schematic diagram of the electrodes of a hydrogen electrolyzer observed with a scanning electron microscope at a magnification of 50x in one embodiment of this application.

[0029] Figure 8 This is a comparison diagram showing the performance tests of the electrodes in a hydrogen electrolyzer in one embodiment and a comparative example of this application.

[0030] Figure 9-11 This is a schematic diagram of the electrolytic cell in an embodiment of this application.

[0031] Figure 12-15 This is a schematic diagram of the electrodes in an embodiment of this application.

[0032] Figure 16-17 This is a schematic diagram of the surface treatment layer in one embodiment of this application.

[0033] Figure 18 This is a schematic diagram of an electrolytic cell in one embodiment of this application. Detailed Implementation

[0034] The following specific examples illustrate the implementation of this application. Those skilled in the art can easily understand other advantages and effects of this application from the content disclosed in this specification. This application can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of this application.

[0035] It should be understood that this application can be implemented in various forms and should not be construed as being limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this application to those skilled in the art. Unless otherwise specified, “%” and “parts” as shown in the following embodiments refer to “mass %” and “mass parts”, respectively.

[0036] The technical solutions of this application will be further described in detail below with reference to several embodiments and accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0037] In one embodiment of this application, an electrode catalyst is provided for use in an electrolytic hydrogen production device. The electrode catalyst has a nanosheet catalyst structure, wherein the surface of the nanosheet catalyst structure has multiple pores, the size of which is less than 80 nm.

[0038] In one embodiment of this application, the nanosheet catalyst structure includes a coral-like dealloyed nanowire array structure, which has a coral-like porous structure. The length of the nanowire array is, for example, 10 μm to 1100 μm, and the diameter of the nanowires is, for example, 120 nm to 200 nm. In this embodiment, the electrode catalyst includes at least elements M and N, wherein element M is selected from at least one transition metal such as Mn, Cr, Fe, Co, Ni, or Cu, and element N is selected from noble metals such as Ir. The electrocatalyst, for example, comprises the following components by mass percentage: 50% to 70% M, 20% to 50% N, and the remainder being oxygen. By forming a coral-like porous structure, the specific surface area of ​​the electrode catalyst is increased, thereby increasing the contact area with water and improving the catalytic efficiency for the same mass.

[0039] In one embodiment of this application, the specific surface area of ​​the electrode catalyst may be greater than or equal to 10 m². 2 / g. This increases the electrochemical specific surface area of ​​the electrode catalyst, resulting in high exposure of active sites and numerous mass transfer channels, thus improving the catalytic performance of the electrode catalyst. Using the electrode catalyst to form a membrane electrode significantly reduces the amount of precious metals required in the catalyst layer, leading to a substantial decrease in cost.

[0040] In another embodiment of this application, the nanosheet catalyst structure includes a hollow spherical structure or a hollow chain structure. In the hollow spherical structure, the diameter of the hollow spheres is, for example, 3 nm to 25 nm. In the hollow chain structure, the length of the hollow chain is, for example, 10 μm to 1100 μm, and the diameter of the hollow spheres on the hollow chain is, for example, 0.5 μm to 1.5 μm. The hollow structure of the electrode catalyst has a regular shape and uniform size, which is beneficial for fluid transport.

[0041] In another embodiment of this application, the electrode catalyst comprises at least two of a transition metal, a lanthanide rare earth element, and a platinum group noble metal element. The transition metal includes, for example, at least one of Mn, Cr, Zr, Fe, Co, Ni, Cu, Zn, Mo, or W. The platinum group noble metal element includes at least one of Ru, Rh, Pd, Ag, Os, Ir, Pt, or Au. In one embodiment of this application, the electrocatalyst comprises, for example, the following components by mass percentage: 50%–80% transition metal, 20%–40% lanthanide rare earth element and / or platinum group noble metal element, with the remainder being oxygen. In one embodiment of this application, the specific surface area of ​​the electrode catalyst is, for example, 20 m². 2 / g. By forming hollow spherical electrode catalysts, the electrochemical specific surface area of ​​the electrode catalyst can be increased. At the same time, the hollow structure improves the mass transfer efficiency and strength of the catalyst, thereby enhancing the catalytic performance of the electrode catalyst.

[0042] In one embodiment of this application, a method for preparing an electrode catalyst is provided, comprising at least steps S11-S14.

[0043] Step S11: Prepare the metal precursor solution.

[0044] Step S12: Add a morphology inducer to the metal precursor solution.

[0045] Step S13: Under alkaline conditions, the mixture is kept at a preset temperature and stirred for a preset time to obtain an intermediate.

[0046] Step S14: Perform pore-forming treatment on the intermediate to obtain the electrode catalyst.

[0047] In one embodiment of this application, in step S11, the metal precursor solution contains at least two of the following metal elements: transition metals, lanthanide rare earth elements, and platinum group noble metals. The transition metal elements include, for example, at least one of Mn, Cr, Zr, Fe, Co, Ni, Cu, Zn, Mo, or W. The platinum group noble metals include at least one of Ru, Rh, Pd, Ag, Os, Ir, Pt, and Au. The solvent for the metal precursor solution includes pure water, ultrapure water, deionized water, or tap water. The metal element originates from water-soluble metal salts such as metal salts, metal halides, metal sulfates, or metal nitrates. Metal salts are, for example, anions containing metal elements, such as tungstate, molybdate, chloroplatinate, and chloroaurate. The metal salt is added to the solvent, for example, by ultrasonic stirring for 2-5 minutes to obtain the metal precursor solution. In other embodiments, dissolution can also be achieved through other methods. In the metal precursor solution, the concentration of total metal ions is, for example, 0.01 to 1 M.

[0048] In one embodiment of this application, in step S11, different metal precursor solutions are selected to obtain electrode catalysts with different morphologies. In a specific embodiment of this application, to obtain an electrode catalyst with a coral-like porous structure, the metal precursor solution includes at least one transition metal such as Mn, Cr, Fe, Co, Ni, or Cu, and a noble metal such as Ir. In another specific embodiment of this application, to obtain an electrode catalyst with a hollow spherical structure or a hollow chain structure, the metal precursor solution includes at least two of transition metals, lanthanide rare earth elements, and platinum group noble metal elements. The transition metals include, for example, at least one of Mn, Cr, Zr, Fe, Co, Ni, Cu, Zn, Mo, or W, and the platinum group noble metal elements include at least one of Ru, Rh, Pd, Ag, Os, Ir, Pt, or Au.

[0049] In one embodiment of this application, in step S12, different morphology inducers are added to the metal precursor solution to obtain nanosheet catalyst structures with different morphologies. In one embodiment of this application, to obtain a coral-like porous electrode catalyst, a first inducer and a second inducer are added sequentially. The first inducer includes solvents such as metal salts, metal halides, metal sulfates, and metal nitrates, and the metal is selected from at least two elements selected from Mn, Cr, Fe, Co, Ni, Cu, Zn, and platinum group noble metals. The second inducer is selected from at least one organic solvent selected from methanol, ethanol, propanol, acetone, dimethylformamide, cyclohexane, ethyl acetate, and dimethyl sulfoxide. In one embodiment of this application, the concentration of metal ions in the first inducer is, for example, 0.5 M, and the molar ratio of the metal precursor solution, the first inducer, and the second inducer is, for example, 1:1.

[0050] In another embodiment of this application, in step S12, in order to obtain an electrode catalyst with a hollow spherical structure or a hollow chain structure, an organic inducing agent is added, for example, selected from isophthalic acid esters, phthalates, 1,4-diazabicyclo[2.2.2]octane, triethylenediamine, 1,4-dimethylpiperazine, hexamethylenetetramine, pyromellitic acid, pyromellitic tricarboxylic acid, 1,4-bis(1H-pyrazol-4-yl)benzene, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetracarboxylic acid, 2,4,6-tris(4-pyridine) At least one of the following: (-1,3,5-triazine), tris(isobutylaminoethyl)amine, bis(3,5-dicarboxyphenyl)azo, biphenylcarboxylic acid, 2,5-dihydroxyterephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-phenylene diacetic acid, 1,1,2,2-tetra(4-carboxyphenyl)ethylene, 1,3,5-tris(4-carboxyphenyl)benzene, 2-(diphenylphosphino)terephthalic acid, 2-amino-4-hydroxy-6-methylpyrimidine, 2-methylimidazolium, 2-aminoterephthalic acid, terephthalic acid, fumaric acid, and trioctyl trimellitate. The molar ratio of the organic inducer to the total metal ion concentration in the metal precursor solution is, for example, 1:10000 to 100:1.

[0051] In one embodiment of this application, in step S12, the metal precursor solution and the morphology inducer are mixed uniformly, for example, by ultrasonic stirring, for a time of 2 to 5 minutes. In other embodiments, mixing can also be performed by other methods.

[0052] In one embodiment of this application, different metal precursor solutions and morphology inducers are selected according to the preset morphology or performance requirements of the electrode catalyst to be obtained, so as to achieve the production requirements of different morphologies.

[0053] In one embodiment of this application, in step S13, under alkaline conditions, the mixture is kept at a preset temperature and stirred for a preset time to obtain an intermediate. In another embodiment of this application, for example, alkaline substances such as ammonia and potassium hydroxide are added to a mixed solution of a metal precursor solution and a morphology inducer, the pH value is controlled at 8-14, and the mixture is kept at a preset temperature and stirred to obtain solid intermediates with different morphologies.

[0054] In one embodiment of this application, different preset temperatures are used to obtain different morphologies of the electrode catalyst. In one specific embodiment of this application, a coral-like dealloyed nanowire array structure is obtained under the conditions of a first inducing agent and a second inducing agent, at a preset temperature of, for example, 40°C to 80°C and a preset stirring time of, for example, 5 min to 1200 min. In another specific embodiment of this application, a spherical or spherical chain structure is obtained under the conditions of an organic inducing agent, at a preset temperature of, for example, 40°C to 90°C and a preset stirring time of, for example, 5 min to 1200 min.

[0055] In one embodiment of this application, before step S14, the intermediate is first cleaned and filtered to remove impurities. In this embodiment, deionization is used for cleaning, for example. When creating pores in the intermediate, methods such as acid washing or calcination are used to remove some metal, forming pores on the catalyst surface to obtain a porous electrode catalyst. The specific method is selected based on the desired morphology of the prepared electrode catalyst.

[0056] In one embodiment of this application, when creating pores in the coral-like dealloyed nanowire array structure, an acid washing process is employed, for example. Specifically, a mixture of one or more of sulfuric acid, hydrochloric acid, or nitric acid with a concentration of 0.01–1 M is selected and immersed at room temperature for 1–60 minutes to obtain a coral-like porous structure. The acid-washed electrode catalyst is then cleaned and dried before storage, for example, by rinsing with deionized water, followed by drying at 80°C.

[0057] In another embodiment of this application, when creating pores in a spherical or spherical chain structure, pores are created, for example, by acid washing or calcination, to obtain a hollow structure. When acid washing is selected, for example, a mixture of one or more of sulfuric acid, hydrochloric acid, or nitric acid with a concentration of 0.01–1 M is used, and the mixture is soaked at room temperature for 1 min–240 min to obtain a hollow spherical or hollow chain structure. The acid-washed electrode catalyst is then cleaned and dried before storage, for example, by rinsing with deionized water, followed by drying at, for example, 80°C. When calcination is selected, the calcination temperature is, for example, 300°C–900°C, and the calcination time is, for example, 1 min–240 min. Calcination is carried out, for example, in a mixed atmosphere of one or more of N2, Ar, NH4, or air, and after calcination, the catalyst is dried into powder for storage.

[0058] In this application, different metal precursor solutions and morphology inducers are selected to achieve different morphological requirements. Based on the fabricated morphology, different pore-forming methods are chosen to obtain nanosheet catalyst structures with multiple pores on their surface. By controlling the pore-forming time, the pore size is controlled to be less than 80 nm to meet catalytic requirements.

[0059] like Figure 1 As shown, the electrode catalyst of an embodiment of this application was observed using a scanning electron microscope (SEM), and the results were obtained. Figure 1 The scanning electron microscope image shown is from... Figure 1As can be seen, the electrode catalyst prepared in this embodiment has the following microstructure: a coral-like nanowire array structure forming a nanosheet catalyst structure. The length of the nanowire array is, for example, 10 μm to 1100 μm, and the diameter of the nanowire is, for example, 120 nm to 200 nm. Testing revealed that the electrode catalyst prepared in this embodiment contains 70% M, 20% N, and 10% oxygen, with a uniform elemental distribution, improving the consistency of the catalytic effect.

[0060] like Figure 2 and Figure 3 As shown, the electrode catalyst of another embodiment of this application was observed using a scanning electron microscope, and the results were obtained. Figure 2 and Figure 3 The scanning electron microscope image shown is from... Figure 2 It can be seen that the electrode catalyst prepared in this embodiment has a microstructure of hollow spherical structure, and the diameter of the hollow spherical structure is, for example, 3 nm to 25 nm. From... Figure 3 It can be seen that the electrode catalyst prepared in this embodiment has the following microstructure: a hollow chain structure, and the length of the hollow chain is, for example, 10 μm to 1100 μm, and the diameter of the hollow spheres on the hollow chain is, for example, 0.5 μm to 1.5 μm.

[0061] like Figure 4 As shown, Figure 1 The image shows a physical sample and performance curves of the membrane electrode prepared with the electrode catalyst. Figure 4 It can be seen that the electrode catalyst can be uniformly distributed on the substrate to form a membrane electrode, and the membrane electrode product has high quality. At 60℃, with an Ir loading of 0.1 mg Ir·cm⁻¹, -2 Under these conditions, it can be seen from the voltage as a function of current density that 2A·cm⁻¹ 2 The electrolysis voltage is 2.02V, which is relatively low, indicating that the amount of Ir used can be reduced, thus lowering the manufacturing cost.

[0062] Please see Figures 5 to 7 As shown, this application also provides an electrode for an electrolyzer, which includes, for example, a substrate 30, a catalyst layer 20, and a spinel-like structure layer 40. The catalyst layer 20 is on the substrate 30, and the spinel-like structure layer 40 is formed on the top of the catalyst layer 20 and protrudes away from the catalyst layer 20. In the electrode of the electrolyzer provided in this application, the catalyst layer 20 serves as the substrate supporting the spinel-like structure layer 40, which has the advantages of high integrity, low internal stress, and high catalytic activity. It can smoothly cope with complex operating conditions and better couple the fluctuating inputs of photovoltaic and wind power.

[0063] Please see Figure 4As shown in one embodiment of this application, the substrate 30 may be, for example, a nickel mesh, nickel foam, nickel felt, carbon cloth, a diffusion layer substrate, or a porous substrate, but is not limited thereto and may be selected according to actual needs.

[0064] Please see Figures 5 to 7 As shown, in one embodiment of this application, a catalyst layer 20 is disposed on a substrate 30, and the catalyst layer 20 may include a top end 201 and a bottom end 202. The bottom end 202 is in contact with the substrate 30, and the top end 201 extends from the bottom end 202 in a direction away from the substrate 30. Specifically, in one embodiment, the catalyst layer may be formed of nanowires, for example, with nanowire tips. The nanowire tips have the smallest size in the cross-sectional direction of the nanowires, and the nanowire tips are, for example, the top end 201, disposed away from the substrate 30. The nanowires may be metal nanowires. Specifically, in this embodiment, the nanowire precursor is, for example, NiCo nanowires. In the cross-sectional direction of the nanowire precursor, the size of the nanowire precursor is, for example, 2μm-3μm, the length of the nanowire precursor is, for example, 50μm-500μm, and the size of the nanowire tip is, for example, 0.5μm-1μm.

[0065] Please see Figures 5 to 7 As shown, in one embodiment of this application, a spinel-like structure layer 40 is disposed on the top end 201 of the catalyst layer 20 and protrudes in a direction away from the catalyst layer 20. Specifically, in this embodiment, the spinel-like structure layer 40 is disposed on the tip of the nanowire and protrudes in a direction away from the catalyst layer 20. The material of the spinel-like structure layer 40 includes at least one of non-precious metal materials such as nickel, iron, or cobalt. Furthermore, the spinel-like structure layer 40 has a porous structure, so that the electrode of the electrolyzer has a large specific surface area, facilitating the entry of electrolyte into the interior of the spinel-like structure layer 40. The metal material in the spinel-like structure layer 40 acts as a catalyst, catalyzing the electrolytic hydrogen production reaction. Moreover, the porous nature of the spinel-like structure layer 40 facilitates the smooth discharge of hydrogen generated by electrolysis to the outside of the electrode of the electrolyzer, achieving rapid gas-liquid separation, reducing system resistance, and exposing more active sites. Compared with precious metal electrodes, the electrode of the electrolyzer provided in this application uses non-precious metal materials as catalysts, which has the advantages of low preparation cost and large-scale application.

[0066] This application also provides a method for preparing electrodes for an electrolytic cell, which includes at least steps S21-S24.

[0067] Step S21: Provide substrate 30.

[0068] Step S22: Form a catalyst layer 20 on the substrate 30.

[0069] Step S23: Immerse the substrate 30 with the catalyst layer 20 in the electrodeposition solution and pass a fluctuating current into the electrodeposition solution to perform electrodeposition.

[0070] Step S24: A spinel-like structure layer 40 is obtained on the top 201 of the catalyst layer 20, and the spinel-like structure layer 40 is arranged to protrude in a direction away from the catalyst layer 20.

[0071] In one embodiment of this application, after obtaining the substrate 30, a catalyst layer 20 is formed on the substrate 30 in step S22. Specifically, in this embodiment, the formation process of the catalyst layer 20 is described using nanowires as an example. This application does not limit the preparation method and type of nanowires; for example, nanowires can be prepared by spraying, coating, physical vapor deposition, chemical vapor deposition, template method, and solvothermal method. In this embodiment, the preparation process of nanowires is described, for example, by using a solvothermal method to prepare NiCo nanowires. Specifically, the nanowire preparation steps may include steps S121-S123.

[0072] Step S121: Mix the nickel source, cobalt source and urea in a solvent until homogeneous to obtain a mixed solution.

[0073] Step S122: After adding the substrate 30 to the mixed solution, heat it to a preset temperature and keep it at that temperature for a preset time to obtain the reaction product.

[0074] Step S123: The reaction product is cleaned and dried to obtain a substrate 30 loaded with nanowires.

[0075] In one embodiment of this application, in step S121, the nickel source includes, for example, at least one nickel salt such as nickel nitrate, nickel chloride, and nickel sulfate; the cobalt source includes, for example, at least one cobalt salt such as cobalt nitrate, cobalt chloride, and cobalt sulfate; the solvent is, for example, at least one deionized water, methanol, and ethanol; and the molar ratio of the nickel source, cobalt source, and urea is, for example, (0.1-0.2):(0.05-0.15):(5-10). Specifically, in this embodiment, the nickel source is, for example, nickel nitrate hexahydrate; the cobalt source is, for example, cobalt nitrate hexahydrate; and the molar ratio of the nickel source, cobalt source, and urea is, for example, 0.15:0.1:7.2.

[0076] In one embodiment of this application, after obtaining the mixed solution, in step S122, the substrate 30 is added to the mixed solution, for example, placed in a hydrothermal reactor, and then the hydrothermal reactor, substrate, and mixed solution are heated to a preset temperature and held at that temperature for a preset time to obtain the reaction product. The preset temperature is, for example, 70℃-200℃, and the preset time is, for example, 2h-6h. Specifically, at the preset temperature, a nickel source, a cobalt source, and urea react to prepare NiCo nanowires on the substrate 30. The nanowire tips of the NiCo nanowires are positioned away from the substrate 30. Due to incomplete reactions and the presence of solvents, the surfaces of the nanowires and the substrate 30 contain impurities such as cobalt source, nickel source, urea, and solvents.

[0077] In one embodiment of this application, after obtaining the reaction product, in step S123, the reaction product is filtered to obtain nanowires and a substrate 30. Then, the surfaces of the nanowires and substrate 30 are cleaned with a cleaning agent to remove residual nickel source, cobalt source, urea, and solvent. After cleaning, the nanowires and substrate 30 are vacuum dried to remove the cleaning agent and solvent from the surface, obtaining a substrate 30 loaded with nanowires. The cleaning agent includes, for example, at least one of deionized water, methanol, and ethanol, and the vacuum drying temperature is, for example, 50°C-120°C.

[0078] In one embodiment of this application, after obtaining the nanowires and substrate 30, in steps S23 and S24, the substrate 30 with nanowires is immersed in an electrodeposition solution, and a fluctuating current is passed through the electrodeposition solution. The metal ions in the electrodeposition solution are reduced to metal atoms and electrodeposited on the nanowires. Furthermore, during the electrodeposition process, due to the current concentration phenomenon, the current tends to concentrate on the tip of the nanowire, and the electrode spacing at the tip of the nanowire is small. Therefore, metal atoms tend to deposit on the tip of the nanowire, thereby obtaining a spinel-like structure layer 40 on the tip of the nanowire, and the spinel-like structure layer 40 protrudes in a direction away from the nanowire. The electrodeposition solution includes, for example, at least one of nickel sulfate, nickel chloride, nickel sulfamate, nickel nitrate, ferrous sulfate, ferrous chloride, cobalt sulfate, cobalt nitrate, or cobalt chloride; the waveform of the fluctuating current includes, for example, at least one of square wave, ramp wave, triangular wave, or sine wave; the fluctuating period of the fluctuating current is, for example, 0.5h-2h; the peak value of the fluctuating current is, for example, 15A-20A; and the valley value is, for example, 1A-5A.

[0079] In some embodiments, multiple electrodeposited layers may be formed, for example, multiple electrodeposited layers may be stacked on a substrate. In some embodiments, the electrodeposited layers may also be formed directly on the diffusion layer 102 and / or the substrate 30, serving as the catalyst layer 20.

[0080] This application also provides an embodiment and a comparative example. The embodiment is the electrode of the electrolytic cell provided in this application, and in the embodiment, the substrate 30 is, for example, a nickel mesh, the nanowires are, for example, NiCo nanowires, the diameter of the nanowires is, for example, 2μm-3μm, the diameter of the nanowire tips is, for example, 0.5μm-1μm, and the material of the spinel-like structure layer 40 includes nickel. The comparative example is a Raney nickel electrode, and in the Raney nickel electrode of the comparative example, the mass content of nickel is, for example, 85wt%, and the mass content of aluminum is, for example, 15wt%. The electrochemical performance of the electrodes of the embodiment and the comparative example is then tested. Specifically, using the electrode from the examples or comparative examples as the working electrode, a 1 mol / L potassium hydroxide solution as the electrolyte, and at 25°C, an Hg / HgO electrode as the reference electrode and a nickel mesh electrode as the counter electrode, a linearly varying voltage is applied to the working electrode using linear sweep voltammetry. The change in electrolytic current of the working electrode with voltage is measured, and a linear sweep voltammetry diagram is plotted based on the changes. Then, by analyzing the linear sweep voltammetry diagram, the overpotential of the working electrode is obtained, and the hydrogen evolution performance of the working electrode is evaluated based on the overpotential.

[0081] Please see Figure 8 As shown, in one embodiment of this application, based on the linear scan voltammetry of the two working electrodes in the embodiment and comparative examples, it can be concluded that at 3000 A / m 2 In the example, the overpotential of the electrode in the electrolyzer is, for example, 220 mV, while the overpotential of the Raney nickel electrode in the comparative example is, for example, 375 mV. Comparing the overpotentials of the two electrodes, it can be seen that the overpotential of the electrode in the example is lower than that of the Raney nickel electrode in the comparative example, indicating that the electrode in the example has better catalytic ability and activity for the hydrogen evolution reaction compared to the Raney nickel electrode in the comparative example. Therefore, the electrode of the electrolyzer provided in this application has advantages such as high integrity, low internal stress, and high catalytic activity, enabling it to smoothly cope with complex operating conditions and better couple the fluctuating inputs of photovoltaic and wind power.

[0082] This application also provides an electrolytic cell, comprising at least a hydrogen evolution catalytic electrode, an oxygen evolution catalytic electrode, and a membrane. The hydrogen evolution catalytic electrode is the same as the electrode in the aforementioned electrolytic cell, and will not be elaborated upon here. The oxygen evolution catalytic electrode is disposed on one side of the electrode in the electrolytic cell, and the membrane is disposed between the electrode and the oxygen evolution catalytic electrode to prevent the hydrogen produced by the electrolytic electrolysis of the electrode in the electrolytic cell from mixing with the oxygen produced by the electrolytic electrolysis of the oxygen evolution catalytic electrode. Furthermore, this application does not limit the types of oxygen evolution catalytic electrode and membrane, and they can be selected according to actual needs. In the electrolytic cell provided by this application, the electrodes of the electrolytic cell have high catalytic activity for the hydrogen evolution reaction, thereby improving the efficiency and yield of hydrogen production by electrolysis, and can be widely applied, for example, it can be used in high-electric-density electrolytic cells.

[0083] In one embodiment of this application, the membrane is, for example, a polyphenylene sulfide (PPS) membrane, an organic-inorganic composite membrane, or a hydroxide ion exchange membrane. The thickness of the PPS membrane is, for example, 0.5 mm to 1 mm, and the thickness of the organic-inorganic composite membrane is, for example, 0.2 mm to 0.8 mm.

[0084] It is worth noting that the electrode and catalyst layer 20 of this application can be applied in electrolyzers suitable for catalyst electrodes, such as proton exchange membrane (PEM) electrolyzers, anion exchange membrane (AEM) electrolyzers, alkaline electrolyzers, solid oxide electrolyzers (SOEC), seawater electrolyzers, and high-current-density (e.g., 6,000 A / m) electrolyzers. 2 Above or 10,000 A / m 2 In the above-mentioned electrolytic cells, chlorine-producing electrolytic cells, salt-precipitating electrolytic cells, chlor-alkali electrolytic cells, hydrogen-producing electrolytic cells, or other electrolytic cells using catalyst electrodes. In this case, the electrolysis device (such as an electrolytic cell) or system using the catalyst of this application may include a membrane layer 101, a diffusion layer 102, and a catalyst layer 20, wherein the catalyst layer 20 is located between the membrane layer 101 and the diffusion layer 102.

[0085] In some embodiments, such as Figure 9 As shown, the catalyst layer 20 of this application can be applied in an electrolyzer, which includes a membrane layer 101, at least two diffusion layers 102, and a catalyst layer 20. The diffusion layers 102 are located on opposite sides of the membrane layer 101. The catalyst layer 20 is formed between the membrane layer 101 and the diffusion layers 102. In one embodiment, the catalyst layer 20 may be formed on one side surface of the diffusion layer 102, close to the membrane layer 101. In another embodiment, the catalyst layer 20 may also be formed on both sides of the diffusion layer 102. In yet another embodiment, the catalyst layer 20 may be formed on both sides of the membrane layer 101. It is worth noting that the membrane layer 101 can be a diaphragm, proton exchange membrane (PEM), anion exchange membrane, bipolar membrane, cation exchange membrane, or other membranes used for electrolysis, and the diffusion layer 102 can be a nickel mesh, nickel foam, nickel felt, carbon cloth, a diffusion layer substrate, or a porous substrate, etc.

[0086] In some embodiments, such as Figure 9 As shown, the electrolytic cell (or electrolytic device) of this application may include multiple electrolytic units (or electrolytic chambers), and each electrolytic unit may include a membrane layer 101, at least two electrodes and a catalyst layer 20.

[0087] In some embodiments, such as Figure 10As shown, the catalyst layer 20 of this application can be applied in an electrolytic cell, which may include a film layer 101, at least two diffusion layers 102, at least two electrode plates 103, and an electrode plate 104. The diffusion layers 102 are located on opposite sides of the film layer 101. The electrode plates 103 are formed between the film layer 101 and the diffusion layers 102. The electrode plates 103 may be anode electrode plates and cathode electrode plates, and the electrode plates 103 may include the catalyst layer 20 and a substrate 30. The catalyst layer 20 may be formed on one side surface of the substrate 30 and close to the film layer 101, or the catalyst layer 20 may be formed on both sides of the substrate 30 to form cathode or anode electrode plates.

[0088] It is worth noting that the membrane layer 101 can be a diaphragm, proton exchange membrane (PEM), anion exchange membrane, bipolar membrane, cation exchange membrane, or other membrane layers used for electrolysis, and the diffusion layer 102 and / or substrate 30 can be a nickel mesh, nickel foam, nickel felt, carbon cloth, diffusion layer substrate, or porous substrate, etc. In some embodiments, Figure 10 The substrate 30 of the intermediate electrode sheet can also serve as a diffusion layer.

[0089] In one embodiment, such as Figure 11 As shown, the electrolyzer is, for example, an AEM electrolyzer, which may include a membrane layer 101, at least two diffusion layers 102, at least two catalyst layers 20, and electrode plates 104. The diffusion layers 102 are located on opposite sides of the membrane layer 101. The membrane layer 101 is an anion exchange membrane. The catalyst layers 20 are formed on the surface of the diffusion layers 102, close to the membrane layer 101. Alternatively, the catalyst layers 20 may be formed on both sides of the diffusion layers 102, serving as an anode electrode and a cathode electrode, respectively. The anode electrode may also include a hydrogen removal layer 105, which is formed on the catalyst layer 20 on the anode side, close to the membrane layer 101, to remove hydrogen leaked to the anode side. The catalyst layer 20 and / or the hydrogen removal layer 105 may be formed by coating, spraying, thermal spraying, blade coating, spin coating, printing, heat treatment, in-situ growth, electrodeposition, vapor deposition, transfer printing, or dip coating.

[0090] In different embodiments, such as Figure 12-15As shown, the cross-sectional structure of the catalyst layer 20 can have different structures or textures, such as a sheet-like stacked structure, a porous structure, a filamentous textured structure, a particle stacked structure, a coral-like textured structure, or other cross-sectional structures or textures. In one embodiment, the catalyst layer 20 can have different structural textures in different regions. Specifically, in one embodiment, the catalyst layer 20 may include a plurality of first catalyst regions 201 and a plurality of second catalyst regions 202, wherein the structural texture of the catalyst layer 20 in the first catalyst regions 201 is different from that in the second catalyst regions 202. However, it is not limited to this; in one embodiment, the catalyst layer 20 may also include a third catalyst region or more catalyst regions with different structures or textures.

[0091] In different embodiments, such as Figure 14-15 As shown, the catalyst structure of the catalyst layer 20 can have different growth directions. Specifically, the growth direction of the catalyst structure in the first catalyst region 201 of the catalyst layer 20 is different from the growth direction of the catalyst structure in the second catalyst region 202. For example, the angle between the growth direction of the catalyst structure in the first catalyst region and the substrate is between 45 degrees and 90 degrees, or the angle between the growth direction of the catalyst structure in the first catalyst region and the substrate is between 0.1 degrees and 45 degrees. However, this is not the only possibility. In some embodiments, the catalyst layer 20 may include more variations in the growth direction of the catalyst structure. The catalyst layer 20 can be formed by methods such as coating, spraying, thermal spraying, blade coating, spin coating, printing, heat treatment, in-situ growth, electrodeposition, vapor deposition, transfer printing, and dip coating.

[0092] In one embodiment, the growth direction of the catalyst structure can be altered, for example, by selective printing, coating, or spraying process conditions or directions. In one embodiment, the growth direction of the catalyst structure can be altered, for example, by heat treatment process conditions (e.g., slowing diffusion growth rate through low temperature, annealing) or heating location. In one embodiment, the addition of specific surfactants or ligands (e.g., carboxylic acids, amines) can promote the growth of the catalyst structure in other directions. In one embodiment, the morphology of metal nanoparticles and the growth direction of the catalyst structure can be controlled, for example, by electric fields, magnetic fields, or light fields (e.g., photochemical reduction). In one embodiment, the precursor concentration can be adjusted to promote anisotropic growth (e.g., nanowires) through low concentration. In one embodiment, a template (e.g., porous alumina, silica) can be used to confine the growth space or guide the directional alignment of the catalyst structure.

[0093] In different embodiments, such as Figure 12-13As shown, the first catalyst region 201 and / or the second catalyst region 202 are, for example, strip-shaped regions, and the width of the first catalyst region 201 and / or the second catalyst region 202 is, for example, 0.1 to 5 mm, or, for example, 0.3 to 2.5 mm. The first catalyst region 201 and the second catalyst region 202 can be arranged in an alternating pattern, for example, the first catalyst region 201 and the second catalyst region 202 can be arranged in an alternating pattern or in a striped pattern with arbitrary arrangement. However, it is not limited to this, the first catalyst region 201 and / or the second catalyst region 202 can also be, for example, grid-shaped, spot-shaped, concentric circle-shaped, wavy, or other any suitable combination of shapes.

[0094] In different embodiments, multiple microchannels 203 may be formed between the first catalyst region 201 and / or the second catalyst region 202. Specifically, the microchannels 203 may be formed between multiple first catalyst regions 201 or multiple second catalyst regions 202, or the microchannels 203 may be formed between the first catalyst region 201 and the second catalyst region 202. The width of the microchannels 203 may be 0.01–5 mm, for example, 0.01–1 mm, or even 0.1–0.9 mm. The microchannels 203 may expose a portion of the surface of the substrate 30 for rapid diffusion and transport of the gas generated by electrolysis.

[0095] Catalyst regions with different structures or textures can increase the active sites of the catalyst layer 20 and effectively disperse the distribution of active catalyst on the substrate, avoiding excessive agglomeration in local areas and effectively improving the utilization rate of precious metals. Furthermore, the microchannels 203 can also improve electrode performance and reduce the amount of precious metals used (cost).

[0096] In some embodiments, such as Figure 16-17As shown, before forming the catalyst layer 20 on the diffusion layer 102 or the substrate 30, a surface treatment layer 106 can be formed on the surface of the diffusion layer 102 and / or the substrate 30, and then the catalyst layer 20 can be formed on the surface treatment layer 106. This is to ensure the stability of the catalyst layer 20 on the diffusion layer 102 and / or the substrate 30, making the catalyst layer 20 less likely to fall off, thus ensuring the performance and stability of the electrode sheet. The surface treatment layer 106 can be formed on the surface of the diffusion layer 102 and / or the substrate 30 by means of coating, spraying, thermal spraying, scraping, spin coating, printing, heat treatment, in-situ growth, electrodeposition, vapor deposition, transfer printing, dip coating, etc. The material of the surface treatment layer 106 can be the same as or partially the same as the material of the catalyst layer 20, the diffusion layer 102, and / or the substrate 30. The surface roughness of the surface treatment layer 106 can be greater than that of the diffusion layer 102 and the substrate 30. The surface roughness of the surface treatment layer 106 can be 1μm-50μm, for example, 10μm-50μm, or even 20μm-45μm. The specific surface area of ​​the surface treatment layer 106 can be, for example, greater than or equal to 10m². 2 / g, for example, 15m 2 / g-30m 2 The surface area of ​​the surface treatment layer 106 can be greater than that of the diffusion layer 102 and the substrate 30, and the surface stress of the surface treatment layer 106 can be less than that of the diffusion layer 102 and the substrate 30.

[0097] The surface treatment layer 106 can alter the surface structure and / or surface properties of the diffusion layer 102 or the substrate 30. For example, the surface treatment layer 106 can have a porous structure to increase the surface area of ​​the subsequent electrode, exposing more active sites and accelerating the diffusion and reaction process of reactants, thereby effectively improving the electrochemical performance of the electrode. Furthermore, the surface treatment layer 106 can reduce the internal stress of the subsequent electrode and significantly improve the electrode sheet's resistance to current fluctuations.

[0098] In one embodiment, such as Figure 17 As shown, the surface treatment layer 106 may include, for example, an island-like structure composed of nanoparticles, but is not limited thereto. The surface structure of the surface treatment layer 106 may include, for example, one or a combination of several of the following: polyhedral, needle-like, pointed prism-like, spherical, coral-like, sheet-like, porous, hollow spherical, chain-like, fused spherical, or irregular shapes. In one embodiment, the surface of a specific diffusion layer 102 and the substrate 30 may also be selectively etched by an oxidant or acid to form the surface treatment layer 106.

[0099] In some embodiments, such as Figure 18As shown, a structural layer grown on one side of the diffusion layer 102 and / or the substrate 30, and near or far from the film layer 101 (or located between the diffusion layer 102 and the electrode 104), can serve as a support layer 107 to support the space between the diffusion layer 102 and the electrode 104. This support layer 107 can be formed by the catalyst layer 20 or the surface treatment layer 106. However, it is not limited to these methods; the support layer 107 can also be additionally provided and different from the catalyst layer 20 or the surface treatment layer 106. The support layer 107 can be formed on the diffusion layer 102 and / or the substrate 30 by methods such as coating, spraying, thermal spraying, blade coating, spin coating, printing, heat treatment, in-situ growth, electrodeposition, vapor deposition, transfer printing, or dip coating.

[0100] In various embodiments, the above-mentioned electrode catalyst can be applied in electrolysis units or electrolyzers, such as proton exchange membrane (PEM) electrolyzers, anion exchange membrane (AEM) electrolyzers, alkaline electrolyzers, solid oxide electrolyzers (SOEC), seawater electrolyzers, and high-voltage electrolyzers (e.g., 6,000 A / m). 2 Above or 10,000 A / m 2 The above-mentioned electrode catalysts can be used in the electrodes of electrolyzers, chlorine-producing electrolyzers, salt-precipitating electrolyzers, chlor-alkali electrolyzers, hydrogen-producing electrolyzers, or other electrolyzers that use catalyst electrodes. Specifically, the electrode catalysts of this application can be formed on different substrates to form electrode sheets or membrane electrodes. However, this is not the only possibility. In other embodiments, the above-mentioned electrode catalysts can also be applied to the electrodes of other electrochemical devices, such as the electrodes of fuel cells or other electrochemical electrolyzers.

[0101] In some embodiments, this application also provides an electrolyzer including the electrode catalyst described above, wherein the electrode catalyst is, for example, supported on a proton exchange membrane or anion exchange membrane to form a membrane electrode, for example, for cathode or anode catalysis. The electrode catalyst has a high electrochemical surface area, high exposure of active sites, and a large number of mass transfer channels, which can improve catalytic efficiency and reduce production costs. That is, the electrolysis device of this application exhibits higher catalytic activity and better stability, which is beneficial to promoting the development of electrolytic hydrogen or chlorine production technologies.

[0102] In some embodiments, this application proposes an electrode catalyst, its preparation method, and its application. The obtained electrode catalyst has multiple pores on its surface, forming a porous structure, which increases the specific surface area of ​​the electrode catalyst. This increases the contact area with the electrolyte for the same mass, thereby improving catalytic efficiency. Using the electrode catalyst to form a membrane electrode reduces the amount of precious metals in the catalyst layer, significantly lowering costs, while maintaining high catalytic performance. The regular shape and uniform size of the electrode catalyst facilitate fluid transport, improving mass transfer efficiency and intensity, and enhancing catalytic performance. The reactants and reaction conditions can be controlled to obtain an electrode catalyst with a predetermined morphology.

[0103] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A method for preparing an electrode catalyst, characterized in that, include: Preparation of metal precursor solutions; A morphology inducer is added to the metal precursor solution; Under alkaline conditions, the mixture is kept at a preset temperature and stirred for a preset time to obtain an intermediate. The intermediate is subjected to a pore-forming treatment to obtain the electrode catalyst, which comprises a coral-like dealloyed nanowire array structure having a coral-like porous structure.

2. The method according to claim 1, characterized in that, The nanowire array has a length of 10 μm to 1100 μm and a diameter of 120 nm to 200 nm.

3. The method according to claim 2, characterized in that, The metal precursor solution contains at least two of the following metal elements: transition metals, lanthanide rare earth elements, and platinum group noble metals. The transition metal elements include at least one of Mn, Cr, Zr, Fe, Co, Ni, Cu, Zn, Mo, or W. The platinum group noble metal elements include at least one of Ru, Rh, Pd, Ag, Os, Ir, Pt, and Au. The solvent of the metal precursor solution includes pure water, ultrapure water, deionized water, or tap water. The metal elements are derived from water-soluble metal salts such as metal salts, metal halides, metal sulfates, or metal nitrates. Metal salts are acid radicals containing metal elements.

4. The method according to claim 2, characterized in that, The nanowire array structure has the structural formula MN, where M is selected from at least one of Mn, Cr, Fe, Co, Ni or Cu, and N is selected from Ir.

5. The method according to claim 1, characterized in that, A first inducing agent and a second inducing agent are added sequentially. The first inducing agent includes solvents such as metal salts, metal halides, metal sulfates, and metal nitrates. The metal is selected from at least two of Mn, Cr, Fe, Co, Ni, Cu, Zn, and platinum group noble metals. The second inducing agent is selected from at least one of organic solvents such as methanol, ethanol, propanol, acetone, dimethylformamide, cyclohexane, ethyl acetate, and dimethyl sulfoxide.

6. The method according to claim 5, characterized in that, The concentration of metal ions in the first inducer is 0.5M, and the molar ratio of the metal precursor solution, the first inducer, and the second inducer is, for example, 1:

1.

7. The method according to claim 1, further comprising: An organic inducing agent is added, such as an isophthalate, phthalate salt, 1,4-diazabicyclo[2.2.2]octane, triethylenediamine, 1,4-dimethylpiperazine, hexamethylenetetramine, pyromellitic acid, pyromellitic tricarboxylic acid, 1,4-bis(1H-pyrazol-4-yl)benzene, 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetracarboxylic acid, 2,4,6-tris(4-pyridyl)-1,3,5-triazine, tris(isobutylaminoethyl) At least one of the following: amine, bis(3,5-dicarboxyphenyl)azo, biphenylcarboxylic acid, 2,5-dihydroxyterephthalic acid, 2,6-naphthalenedicarboxylic acid, 1,4-phenylene diacetic acid, 1,1,2,2-tetra(4-carboxyphenyl)ethylene, 1,3,5-tris(4-carboxyphenyl)benzene, 2-(diphenylphosphino)terephthalic acid, 2-amino-4-hydroxy-6-methylpyrimidine, 2-methylimidazolium, 2-aminoterephthalic acid, terephthalic acid, fumaric acid, and trioctyl trimellitate.

8. The method according to claim 7, characterized in that, The ratio of the organic inducer to the total metal ion molar concentration in the metal precursor solution is, for example, 1:10000 to 100:

1.

9. The method according to claim 1, characterized in that, Alkaline substances such as ammonia and potassium hydroxide are added to a mixed solution of metal precursor solution and morphology inducer, and the pH value is controlled at 8-14. The mixture is kept warm and stirred to obtain solid intermediates with different morphologies.

10. The method according to claim 1, characterized in that, The intermediate is cleaned and filtered to remove impurities. When creating pores in the intermediate, acid washing or calcination is used to remove some metals and form pores on the catalyst surface to obtain a porous electrode catalyst.

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