Electrode material for electrolyzing water and preparation method

Abstract

The invention relates to the technical field of water electrolysis hydrogen production materials, in particular to an electrode material for water electrolysis and a preparation method, the electrode material comprises a base material and a catalyst active layer, and the catalyst active layer uniformly covers the surface of the base material to form the electrode material for water electrolysis; the base material plays a role in improving the current density, the catalyst active layer can improve the efficiency of converting electric energy into chemical energy, and the energy consumption of the water electrolysis hydrogen production technology is reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hydrogen production by water electrolysis, and particularly relates to an electrode material for water electrolysis and a preparation method. BACKGROUND

[0002] In recent years, green hydrogen and green hydrogen production materials have been a global focus. Water electrolysis using renewable energy to produce hydrogen is a clean, low-carbon and environmentally friendly technology. One of the current bottlenecks of this technology is high energy consumption, which is mainly caused by poor electrochemical performance of electrode materials, specifically manifested as low current density, high cell voltage and insufficient stability. Alkaline water electrolysis for hydrogen production is the most mature, lowest cost and most widely promoted technology. The present application specifically relates to electrode materials, catalysts and preparation methods applied to this technology.

[0003] Patent No. CN220335315U introduces an electrode mesh with an elastic support body, which can increase the current density by increasing the current contact points. The patent describes the structure of the elastic support body in detail. Patent No. CN222524697U discloses an electrode mesh with an elastic support body, which further improves the installation structure of the electrode mesh based on the electrode mesh with an elastic support body disclosed in Patent No. CN220335315U, improves the installation efficiency and ensures the stability of the equipment. Patent No. CN220952095U describes a support structure for water electrolysis, which has similar gain effects as the electrode mesh with an elastic support body disclosed in Patent No. CN220335315U. Patent No. CN118773637A introduces an elastic support body and an elastic support composite electrode, and emphasizes the structure, composition, fitting method and technical parameters of the elastic support body and the elastic support composite electrode.

[0004] The above-mentioned existing technologies disclosed in the patents reasonably design the structure of the elastic support body, increase and improve the current contact points, and achieve the effect of increasing the current density of the electrode mesh. However, this structure of the electrode mesh cannot fundamentally solve the bottleneck of high energy consumption in water electrolysis for hydrogen production. SUMMARY

[0005] To solve the above-mentioned problems, the present application provides an electrode material for water electrolysis and a preparation method, aiming to reduce the energy consumption of water electrolysis.

[0006] To achieve the above-mentioned purposes, the present application adopts the following technical solutions:

[0007] An electrode material for water electrolysis, comprising a substrate and a catalyst active layer, wherein the catalyst active layer uniformly covers the surface of the substrate to form an electrode material for water electrolysis;

[0008] The substrate is any one of iron, cobalt, nickel metal or an alloy with any one or more of the three elements as the main component;

[0009] The catalyst is one or a combination of several of the metals, non-metals, alloys or compounds of elements with atomic numbers from 3 to 86.

[0010] Preferably, the geometric shape of the electrode material is a planar net, a punched plate net structure, a porous foam structure, a wave structure and an elastic support net structure.

[0011] A method for preparing an electrode material for electrolyzing water, comprising the following steps:

[0012] Step 1, pretreatment of the substrate;

[0013] The pretreatment includes any one or a combination of several of sand blasting, alkaline cleaning, acid cleaning, and electrochemical degreasing;

[0014] The sand blasting material is selected from one or a combination of several of brown corundum, white corundum, silicon carbide, glass beads, and ceramic beads with a particle size of 40-100 mesh; the substrate passes through the sand blasting material at a speed of 5-20 cm / s under a spraying pressure of 0.1-0.4 MPa;

[0015] The alkaline cleaning is soaking the substrate in an alkaline solution with a mass fraction of 20-40% for 1-5 h;

[0016] The acid cleaning is soaking the substrate in an acidic solution with a mass fraction of 10-18% for 2-15 min;

[0017] The electrochemical degreasing is placing the substrate as an anode in a sodium hydroxide solution with a concentration of 80-120 g / L, treating it at room temperature at a current density of 10-20 A / dm 2 for 1-3 min, rinsing it with deionized water until it is neutral, and blowing it dry at 60°C;

[0018] Step 2, uniformly covering the catalyst active layer on the surface of the substrate using five surface preparation techniques: thermal spraying, thermal decomposition, electroplating, electrodeposition, and hydrothermal method.

[0019] Preferably, the alkaline solution is any one or a mixture of both of potassium hydroxide or sodium hydroxide solution; the acidic solution is any one or a mixture of several of hydrochloric acid, sulfuric acid, oxalic acid, and citric acid.

[0020] Preferably, the process flow of preparing the electrode material by thermal spraying method is as follows: spraying nickel powder and aluminum powder with particle size of 30-100 μm at a mass ratio of 9:1-7:3 and a speed of 5-30 cm / s on the pretreated substrate, repeating the above process for 3-10 times, and finally activating the sprayed substrate in 20-50% alkali solution at 30-70°C for 5-10 h.

[0021] Preferably, the alkali solution is a mixture of potassium hydroxide or sodium hydroxide solution.

[0022] Preferably, the process flow of preparing the electrode material by thermal decomposition method is as follows: dissolving ammonium salt, chloride salt, sulfate salt, nitrate salt containing platinum group noble metal in a solution containing monohydric alcohol or polyhydric alcohol with one to six carbon atoms, and uniformly brushing the prepared solution on the pretreated substrate, calcining at 200-700°C for 0.5-2 h, and repeating the brushing and calcining process for 5-15 times.

[0023] Preferably, the process flow of preparing the electrode material by electroplating method is as follows: placing the pretreated substrate as cathode in a solution containing 100-220 g / L of nickel sulfate, 10-80 g / L of nickel chloride, 30-100 g / L of boric acid and 10-30 g / L of ammonium molybdate, and electroplating at a current density of 1-5 A / dm2 at 20-60°C for 0.5-3 h.

[0024] Preferably, the process flow of preparing the electrode material by electrodeposition method is as follows: placing the pretreated substrate as cathode in a solution containing 10-100 g / L of nickel sulfate, 5-30 g / L of ammonium nitrate, 5-20 g / L of boric acid and 10-50 g / L of citric acid, and electrodeposition at a current density of 0.02-0.5 A / dm2 at 20-50°C for 0.2-1 h.

[0025] Preferably, the process flow of preparing the electrode material by hydrothermal method is as follows: placing the pretreated substrate in a solution containing 2-15 g / L of nickel nitrate, 2-15 g / L of cobalt nitrate, 20-40 g / L of urea and 5-20 g / L of ammonium fluoride, and keeping in a hydrothermal reactor at 120-160°C for 2-4 h.

[0026] Compared with the elastic support without catalyst coating, the electrode material can not only improve the current density of electrolytic water, but also effectively reduce the overpotential of cathodic reaction, and reduce the energy consumption of the electrode material for electrolytic water.

[0027] Through pretreatment of the substrate, the surface of the substrate is roughened and cleaned, and the adhesion between the substrate and the catalyst coating is improved. BRIEF DESCRIPTION OF DRAWINGS

[0028] Fig. 1 Figure 3 is a comparison chart of the cathode polarization curves of the electrode material of the elastic support with catalyst coating and the elastic support without catalyst coating in Example 3 of the present application;

[0029] Fig. 2 Figure 4 is a comparison chart of the cell voltage and energy consumption curves of the electrode material of the elastic support with catalyst coating and the elastic support without catalyst coating in Example 3 of the present application;

[0030] Fig. 3 Figure 5 is a comparison chart of the long-term operation stability curves of the electrode material of the elastic support with catalyst coating and the elastic support without catalyst coating in Example 3 of the present application. DETAILED DESCRIPTION

[0031] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is further described in detail below with reference to the accompanying drawings and examples.

[0032] The electrode material for electrolyzing water provided by the present application comprises a substrate and a catalyst active layer, the catalyst active layer uniformly covers the surface of the substrate to form the electrode material for electrolyzing water; wherein the substrate is any one of iron, cobalt and nickel metal elements or an alloy with any one or more of the three elements as the main component; the substrate in the embodiment of the present application is preferably a nickel mesh or a stainless steel mesh; the catalyst is one or a combination of several of the metal, non-metal, alloy and compound composed of elements with atomic number 3-86.

[0033] The geometric shape of the electrode material is a planar mesh, a plate mesh punching structure, a porous foam structure, a wave shape structure and an elastic support mesh structure.

[0034] A preparation method of the electrode material for electrolyzing water comprises the following steps:

[0035] Step 1, pretreatment of the substrate: including any one or a combination of several of sandblasting, alkali washing, acid washing and electrochemical degreasing;

[0036] Specifically, the sandblasting material is selected from one or a combination of several of brown corundum, white corundum, silicon carbide, glass beads and ceramic beads with particle size of 40-100 mesh; the sandblasting material in the embodiment of the present application is preferably white corundum with particle size of 60 mesh or 80 mesh; the substrate continuously passes through the sandblasting area at a speed of 5-20 cm / s, and the sandblasting material acts on the surface of the substrate at a spraying pressure of 0.1-0.4 MPa.

[0037] Specifically, the alkali washing is to immerse the substrate in an alkaline solution with mass fraction of 20%-40% for 1-5 h; the alkaline solution is any one or a combination of the two of potassium hydroxide solution or sodium hydroxide solution; the alkaline solution in the embodiment of the present application is preferably sodium hydroxide solution.

[0038] Specifically, pickling involves immersing the substrate in an acidic solution with a mass fraction of 10% to 18% for 2 to 15 minutes; the acidic solution is any one or a combination of hydrochloric acid, oxalic acid, and citric acid.

[0039] Specifically, electrochemical degreasing involves placing the substrate as the anode in an 80–120 g / L sodium hydroxide solution at room temperature, using an A / dm³ flow rate. 2 The current density treatment lasts for 1 to 3 minutes, preferably 2 minutes in this embodiment of the invention; then it is rinsed with deionized water until neutral and dried at 60°C.

[0040] Step 2: The catalyst active layer is uniformly covered on the substrate surface using five surface preparation technologies: thermal spraying, thermal decomposition, electroplating, electrodeposition, and hydrothermal method to form an electrode material. The preparation of the electrode material is a single process or a combination of several of the above processes. The electrode material has an electrochemical response to the hydrogen evolution reaction, oxygen evolution reaction, oxygen reduction reaction, and urea oxidation reaction, and lowers the energy barrier of the reaction.

[0041] Specifically, the process for preparing this electrode material by thermal spraying is as follows: nickel powder and aluminum powder with a particle size of 30μm to 100μm are sprayed onto the pretreated substrate at a mass ratio of 9:1 to 7:3 and a speed of 5cm / s to 30cm / s. The above process is repeated 3 to 10 times. Finally, the sprayed substrate is placed in a 20% to 50% alkaline solution and activated at 30 to 70°C for 5 to 10 hours. The alkaline solution is one or a mixture of potassium hydroxide or sodium hydroxide solution.

[0042] Preferably, in the embodiments of the present invention, the particle size of both nickel powder and aluminum powder is 45μm, the mass ratio of nickel powder to aluminum powder is 8:2, the spraying speed is 25cm / s, the step is repeated 5 times, and finally the substrate is placed in a 30% potassium hydroxide solution and immersed at 60°C for 8 hours for activation.

[0043] Specifically, the process for preparing this electrode material by thermal decomposition is as follows: ammonium salts, chloride salts, sulfates, and nitrates containing platinum group noble metals are dissolved in a solution of monohydric or polyhydric alcohols containing one to six carbon atoms, and the prepared solution is uniformly coated onto the pretreated substrate and calcined at 200℃ to 700℃ for 0.5 to 2 hours. The above coating and calcination process is repeated 5 to 15 times.

[0044] Preferably, in this embodiment of the invention, the platinum group metal solution is n-butanol containing 20 g / L ruthenium trichloride. The prepared solution is uniformly brushed onto the pretreated substrate and calcined at 500°C for 2 hours. The brushing and calcination process is repeated 9 times.

[0045] Specifically, the electroplating process for preparing this electrode material is as follows: The pretreated substrate is placed in a solution containing 100–220 g / L nickel sulfate, 10–80 g / L nickel chloride, 30–100 g / L boric acid, and 10–30 g / L ammonium molybdate as the cathode. The electrode is then plated at 20°C–60°C at a rate of 1 A / dm². 2 ~5A / dm 2 Electroplating was performed at a current density of 0.5–3 hours.

[0046] Preferably, in this embodiment of the invention, the pretreated substrate is placed in a solution containing 150 g / L nickel sulfate, 30 g / L nickel chloride, 55 g / L boric acid, and 12 g / L ammonium molybdate as a cathode, and the solution is heated at 40°C and 4 A / dm². 2 Electroplating was performed at a current density for 2 hours.

[0047] Specifically, the electrode deposition process for preparing this electrode material is as follows: The pretreated substrate is placed in a solution containing 10–100 g / L nickel sulfate, 5–30 g / L ammonium nitrate, 5–20 g / L boric acid, and 10–50 g / L citric acid as the cathode. The electrode is deposited at 20°C–50°C at a current of 0.02 A / dm³. 2 ~0.5A / dm 2 Electrodeposition was performed at a current density of 0.2–1 h.

[0048] Preferably, in this embodiment of the invention, the pretreated substrate is placed in a solution containing 60 g / L nickel sulfate, 18 g / L ammonium nitrate, 20 g / L boric acid, and 25 g / L citric acid as a cathode, at 30°C and 0.1 A / dm². 2 Electrodeposition was performed at a current density for 0.5 h.

[0049] Specifically, the process for preparing the electrode material by hydrothermal method is as follows: the pretreated substrate is placed in a solution containing 2-15 g / L nickel nitrate, 2-15 g / L cobalt nitrate, 20-40 g / L urea, and 5-20 g / L ammonium fluoride, and kept at 120-160°C for 2-4 hours.

[0050] Preferably, in this embodiment of the invention, the pretreated substrate is placed in a solution containing 12 g / L nickel nitrate, 12 g / L cobalt nitrate, 25 g / L urea, and 25 g / L ammonium fluoride, and kept at 140°C for 2 hours in a hydrothermal reactor.

[0051] Preferably, in the embodiments of the present invention, when using the thermal spraying and hydrothermal composite process, the nickel-aluminum mixed powder is first uniformly sprayed onto the surface of the pretreated substrate, wherein the particle size of both nickel powder and aluminum powder is 60 μm, the mass ratio of nickel powder to aluminum powder is 8.5:1.5, the spraying speed is 30 cm / s, and this step is repeated 10 times. Then, it is placed in a 20% potassium hydroxide solution and soaked at 70°C for 10 h for activation. The obtained electrode is placed in a solution containing 15 g / L nickel nitrate, 7.5 g / L cobalt nitrate, 20 g / L urea, and 8 g / L ammonium fluoride, and kept at 120°C for 2 h in a hydrothermal reactor.

[0052] Example 1

[0053] A method for preparing an electrode material for water electrolysis includes the following steps:

[0054] Step 1, Pretreatment of substrate: Sandblasting, using a nickel mesh with a 46 mesh, 0.25mm wire diameter, and twill weave as the substrate, continuously passing it through white corundum with a sandblasting pressure of 0.35MPa and a sandblasting material of 60 mesh size at a speed of 8cm / s; use compressed air to blow away the floating dust and powder on the surface of the substrate twice.

[0055] Step 2: Uniformly spray the nickel-aluminum mixed powder onto the surface of the substrate after the pretreatment in Step 1; wherein the particle size of both nickel powder and aluminum powder is 45μm, the mass ratio of nickel powder to aluminum powder is 8:2, the spraying distance is 15cm, the spraying speed is 25cm / s, and the above process is repeated 5 times; finally, place the sprayed substrate in a 30% potassium hydroxide solution, soak it at 60℃ for 8h for activation, rinse it clean, and dry it to obtain the finished electrode material with a coating thickness of 85μm.

[0056] Example 2

[0057] A method for preparing an electrode material for water electrolysis includes the following steps:

[0058] Step 1, Pretreatment of substrate: Sandblasting, using a nickel mesh with a 46-mesh, 0.19mm wire diameter and plain weave, continuously passing it through white corundum with a sandblasting pressure of 0.20MPa and a sandblasting material of 80-mesh particle size at a speed of 20cm / s; use compressed air to blow away the floating dust and powder on the surface of the substrate.

[0059] Pickling: Place the substrate in 10% hydrochloric acid and let it stand for 3 minutes, then rinse it with deionized water and dry it.

[0060] Step 2: Coating with platinum group elements and calcining at high temperature; wherein, the platinum group noble metal solution is n-butanol containing 20g / L ruthenium trichloride. The prepared solution is evenly coated onto the substrate after the pretreatment in step 1 with a wool brush, and calcined at 500℃ for 2h. The above coating and calcination process is repeated 9 times to obtain the electrode material with a noble metal catalyst coating.

[0061] Example 3

[0062] A method for preparing an electrode material for water electrolysis includes the following steps:

[0063] Step 1, Pretreatment of the substrate: Sandblasting. The substrate is a 46-mesh nickel mesh with a wire diameter of 0.25mm and a twill weave. The bottom is welded with a double-wire, double-layer elastic support nickel mesh with a wire diameter of 0.19mm. The mesh is continuously passed through white corundum with a sandblasting pressure of 0.20MPa and a sandblasting material of 80-mesh particle size at a speed of 5cm / s. Compressed air is used to blow away the floating dust and powder on the surface of the substrate.

[0064] Alkaline washing: Place the substrate in a 30% sodium hydroxide solution and let it stand for 2 hours, then rinse it with deionized water and dry it.

[0065] Electrochemical degreasing involves placing the substrate as the anode in an 80 g / L sodium hydroxide solution at room temperature and at 20 A / dm². 2 Degrease under current density for 2 minutes, rinse with deionized water until neutral, and blow dry at 60°C;

[0066] Pickling: Place the substrate in 10% hydrochloric acid and let it stand for 2 minutes, then rinse it with deionized water and dry it.

[0067] Step 2: Electroplating a nickel-molybdenum alloy catalyst coating; the substrate pretreated in Step 1 is placed in a solution containing 150 g / L nickel sulfate, 30 g / L nickel chloride, 55 g / L boric acid, and 12 g / L ammonium molybdate as a cathode, at 40°C and 4 A / dm². 2 Electroplating was performed at a current density for 2 hours.

[0068] Example 4

[0069] A method for preparing an electrode material for water electrolysis includes the following steps:

[0070] Step 1, Pretreatment of substrate: Sandblasting, using a 40-mesh stainless steel mesh with a wire diameter of 0.18mm and plain weave, continuously passing it through white corundum with a sandblasting pressure of 0.10MPa and a sandblasting material of 80-mesh particle size at a speed of 20cm / s; use compressed air to blow away the floating dust and powder on the surface of the substrate.

[0071] Alkaline washing: Place the substrate in a 40% sodium hydroxide solution and let it stand for 5 hours, then rinse it with deionized water and dry it.

[0072] Electrochemical degreasing involves placing the substrate as the anode in a 120 g / L sodium hydroxide solution at room temperature and at 10 A / dm³. 2 Degrease under current density for 2 minutes, rinse with deionized water until neutral, and blow dry at 60°C;

[0073] Pickling: Place the substrate in a solution containing 1% hydrochloric acid, 5% oxalic acid and 12% citric acid and let it stand for 15 minutes. Rinse it with deionized water and dry it.

[0074] Step 2, electrodeposition of nickel hydroxide catalyst coating; the substrate pretreated in Step 1 is placed in a solution containing 60 g / L nickel sulfate, 18 g / L ammonium nitrate, 20 g / L boric acid, and 25 g / L citric acid as a cathode, at 30°C and 0.1 A / dm². 2 Electrodeposition was performed at a current density for 0.5 h.

[0075] Example 5

[0076] A method for preparing an electrode material for water electrolysis includes the following steps:

[0077] Step 1, Pretreatment of substrate: Sandblasting, using a 40-mesh stainless steel mesh with a wire diameter of 0.25mm and plain weave, continuously passing it through a blasting pressure of 0.30MPa and a blasting material of 60-mesh white corundum at a speed of 10cm / s; use compressed air to blow away the floating dust and powder on the surface of the substrate.

[0078] Alkaline washing: Place the substrate in a 20% sodium hydroxide solution and let it stand for 1 hour, then rinse it with deionized water and dry it.

[0079] Electrochemical degreasing involves placing the substrate as the anode in a 120 g / L sodium hydroxide solution at room temperature and at 10 A / dm³. 2 Degrease under current density for 2 minutes, rinse with deionized water until neutral, and blow dry at 60°C;

[0080] Pickling: Place the substrate in a solution containing 1% hydrochloric acid, 5% oxalic acid and 12% citric acid and let it stand for 15 minutes. Rinse it with deionized water and dry it.

[0081] Step 2, in-situ growth of nickel-cobalt hydroxide catalyst coating; the substrate pretreated in Step 1 is placed in a solution containing 12 g / L nickel nitrate, 12 g / L cobalt nitrate, 25 g / L urea and 25 g / L ammonium fluoride, and kept at 140°C for 2 h in a hydrothermal reactor.

[0082] Example 6

[0083] A method for preparing an electrode material for water electrolysis includes the following steps:

[0084] Step 1, Pretreatment of substrate: Sandblasting, using a nickel mesh with a 60-mesh, 0.25mm wire diameter and twill weave as the substrate, and passing it through white corundum with a sandblasting pressure of 0.4MPa and a sandblasting material of 80-mesh particle size at a speed of 12cm / s; use compressed air to blow away the floating dust and powder on the surface of the substrate 3 times.

[0085] Step 2: The nickel-aluminum mixed powder is uniformly sprayed onto the surface of the pretreated substrate. The particle size of both nickel and aluminum powder is 60 μm, the mass ratio of nickel powder to aluminum powder is 8.5:1.5, the spraying distance is 15 cm, and the spraying speed is 30 cm / s. This step is repeated 10 times. Then, the electrode is placed in a 20% potassium hydroxide solution and soaked at 70°C for 10 h for activation. The resulting electrode is placed in a solution containing 15 g / L nickel nitrate, 7.5 g / L cobalt nitrate, 20 g / L urea, and 8 g / L ammonium fluoride and kept at 120°C for 2 h in a hydrothermal reactor.

[0086] This embodiment employs a combined process of thermal spraying and hydrothermal method, which can further reduce the overpotential and energy consumption of electrode materials.

[0087] The product prepared according to this invention was experimentally analyzed, taking the product prepared in Example 3 as the subject, see [link to relevant documentation]. Figs. 1-3 The electrode material prepared in Example 3 has a strength of 100 A / m. 2 The hydrogen evolution overpotential at current density is less than 115 mV; 3000 A / m 2 The cell voltage at the current density is 1.80V, and the energy consumption is 4.3kWh / Nm. 3 It outperforms the voltage of a single elastic support (2.01V) and has an energy consumption of 4.8kWh / Nm³. 3 Furthermore, by selecting appropriate pretreatment techniques and combining them with surface preparation techniques, this invention enables the catalyst coating to be firmly bonded to substrates of different shapes and structures. At the same time, it can also effectively improve the problems of low substrate current density, high chamber voltage, and insufficient stability, thus solving the problem of high energy consumption in hydrogen production through water electrolysis.

Claims

1. An electrode material for electrolysis of water, characterized in that, The electrode material for electrolyzing water comprises a substrate and a catalyst active layer uniformly covering the surface of the substrate; The substrate is any one of iron, cobalt and nickel or an alloy mainly composed of any one or more of the three elements; The catalyst is one or a combination of several of the metals, non-metals, alloys and compounds of elements with atomic numbers from 3 to 86.

2. The electrode material for electrolysis of water according to claim 1, wherein, The geometric shape of the electrode material is planar net, plate net punching structure, porous foam structure, wave structure and elastic support net structure.

3. The method of claim 1 or 2, wherein the method is performed in the presence of a reducing agent. The method comprises the following steps: Step 1: pretreatment of the substrate; The pretreatment comprises any one or a combination of several of sand blasting, alkali cleaning, acid cleaning and electrochemical degreasing; The sand blasting material is selected from one or a combination of several of brown corundum, white corundum, silicon carbide, glass beads and ceramic beads with particle sizes of 40-100 mesh; the substrate passes through the sand blasting material at a speed of 5-20 cm / s and under a spraying pressure of 0.1-0.4 MPa; The alkali cleaning is soaking the substrate in an alkaline solution with a mass fraction of 20-40% for 1-5 h; The acid cleaning is soaking the substrate in an acidic solution with a mass fraction of 10-18% for 2-15 min; The electrochemical degreasing is to place the substrate as anode in 80-120 g / L sodium hydroxide solution, at normal temperature, with 10-20 A / dm 2 current density for 1-3 min, rinsing with deionized water to neutral, blowing dry at 60°C; Step 2: uniformly covering the catalyst active layer on the surface of the substrate by using five surface preparation technologies, i.e. thermal spraying, thermal decomposition, electroplating, electrodeposition and hydrothermal method.

4. The production method according to claim 3, characterized by, In step 1, the alkaline solution is any one or a mixture of the two of potassium hydroxide or sodium hydroxide solution; the acidic solution is any one or a mixture of several of hydrochloric acid, sulfuric acid, oxalic acid and citric acid.

5. The preparation method according to claim 3, characterized in that, The process flow of the thermal spraying method for preparing the electrode material is: spraying nickel powder and aluminum powder with particle sizes of 30-100 μm at a mass ratio of 9:1-7:3 on the pretreated substrate at a speed of 5-30 cm / s, repeating the above process for 3-10 times, and finally placing the sprayed substrate in an alkali solution with a concentration of 20-50% at 30-70 ℃ for activation for 5-10 h.

6. The preparation method according to claim 5, characterized in that, The alkali solution is any one or a mixture of the two of potassium hydroxide or sodium hydroxide solution.

7. The preparation method according to claim 3, characterized in that, The process flow of the thermal decomposition method for preparing the electrode material is: dissolving ammonium salt, chloride salt, sulfate salt and nitrate salt containing platinum group noble metal in a solution containing monohydric alcohol or polyhydric alcohol with one to six carbon atoms, uniformly brushing the prepared solution on the pretreated substrate, and calcining at 200-700 ℃ for 0.5-2 h, repeating the brushing and calcining process for 5-15 times.

8. The preparation method according to claim 3, characterized in that, The process flow of the electrode material prepared by the electroplating method is as follows: the pretreated substrate is placed in a solution containing 100-220 g / L of nickel sulfate, 10-80 g / L of nickel chloride, 30-100 g / L of boric acid and 10-30 g / L of ammonium molybdate as a cathode, and is electroplated at a current density of 1 A / dm 2 ~5 A / dm 2 at 20-60°C for 0.5-3 h.

9. The preparation method according to claim 3, characterized in that, The process flow of the electrode material prepared by the electrodeposition method is as follows: the pretreated substrate is placed in a solution containing 10-100 g / L of nickel sulfate, 5-30 g / L of ammonium nitrate, 5-20 g / L of boric acid and 10-50 g / L of citric acid as a cathode, and electrodeposition is carried out at 20-50°C under a current density of 0.02-0.5 A / dm 2 for 0.2-1 h. 2 The process flow of the electrode material prepared by the electrodeposition method is as follows: the pretreated substrate is placed in a solution containing 10-100 g / L of nickel sulfate, 5-30 g / L of ammonium nitrate, 5-20 g / L of boric acid and 10-50 g / L of citric acid as a cathode, and electrodeposition is carried out at 20-50°C under a current density of 0.02-0.5 A / dm 2 for 0.2-1 h. 2 The process flow of the electrode material prepared by the electrodeposition method is 10. The method of claim 3, wherein, The process flow of the hydrothermal method for preparing the electrode material is: placing the pretreated substrate in a solution containing 2-15 g / L of nickel nitrate, 2-15 g / L of cobalt nitrate, 20-40 g / L of urea and 5-20 g / L of ammonium fluoride, and carrying out hydrothermal reaction in a hydrothermal reactor at 120-160 ℃ for 2-4 h.

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