Preparation method and application of three-dimensional porous foam nickel-molybdenum alloy material

Abstract

The invention particularly discloses a preparation method and application of a three-dimensional porous foamed nickel-molybdenum alloy material. The method comprises the steps that S100, a foamed nickel matrix is selected and cleaned; s200, the cleaned foamed nickel matrix is subjected to acid pickling and activation; s300, microcosmic etching is conducted on the surface of the foamed nickel base body subjected to acid pickling activation; and S400, electro-deposition is conducted on the foamed nickel base body obtained after microcosmic etching, and then the three-dimensional porous foamed nickel-molybdenum alloy material for the water electrolysis hydrogen production electrode is obtained. The prepared alloy material is a nickel-molybdenum alloy material with a three-dimensional porous structure, and the main component of the nickel-molybdenum alloy material is nickel-molybdenum alloy, so that compared with an existing hydrogen production electrode material, the nickel-molybdenum material is lower in price, and the alloy material has higher porosity and specific surface area due to the three-dimensional porous structure; according to the present invention, the hydrogen production electrode can have more hydrogen evolution active sites, the catalytic activity is high, the nickel-molybdenum alloy structure is stable, and the catalytic activity can be maintained for a long time in the alkaline environment.

Description

Technical Field

[0001] The present application belongs to the technical field of electrolytic water catalysis, and in particular, relates to a method for preparing a three-dimensional porous nickel-molybdenum alloy foam material and its application. Background Art

[0002] At present, most of the electrolytic water catalytic electrodes use a woven nickel mesh as a substrate, sprayed with Raney nickel, and then achieve electrolytic water catalysis. The technical process is mature, and the corresponding products have occupied the dominant market of electrolytic water hydrogen production electrodes. However, the product still has great technical limitations. For example, the number of active sites in its catalytic material cannot achieve a multiple breakthrough due to the limitations of the material structure of the woven nickel mesh substrate itself. During the operation of the electrolyzer, due to the strong corrosion properties of extreme environments such as high pressure and strong alkali, the sprayed catalyst Raney nickel is very easy to fall off over time, causing the energy consumption of the electrolytic cell to increase while its electrolytic performance is greatly reduced. At the same time, the replacement of the electrolytic cell electrodes and the cleaning of the cell have also become part of the factory's inevitable cost expenditure. In order to achieve a breakthrough in the performance of this electrode material, precious metals are added to some of the electrodes of this electrode material to improve the performance of the electrode material, but this also increases the cost of the electrode material, and even increases the cost exponentially. Summary of the invention

[0003] In order to solve the above technical problems, the present application provides a method for preparing a three-dimensional porous foam nickel-molybdenum alloy material, the method comprising:

[0004] S100, selecting a foam nickel substrate and cleaning it;

[0005] S200, nickel foam substrate after pickling activation and cleaning;

[0006] S300, micro-etching the surface of the nickel foam substrate after pickling and activation;

[0007] S400, electroplating the micro-etched nickel foam substrate to obtain a three-dimensional porous nickel-molybdenum alloy foam material for an electrode for hydrogen production by electrolysis of water.

[0008] In some embodiments, the step S100 specifically includes: selecting a nickel foam substrate, soaking the nickel foam substrate with anhydrous ethanol and acetone, and then performing ultrasonic cleaning, wherein the ultrasonic cleaning time is 1-6 minutes and the ultrasonic power is 150-300W.

[0009] In some embodiments, the step S200 is specifically as follows: placing the nickel foam substrate after ultrasonic cleaning in dilute sulfuric acid with a volume fraction of 9-12%, thereby removing the oxidized portion on the surface of the nickel foam substrate, and the acid pickling activation time is 3-5 minutes.

[0010] In some embodiments, the step S300 is specifically as follows: at room temperature, the surface of the nickel foam substrate after pickling and activation is micro-etched based on a pre-configured etching solution, and the etching time is 5-15s.

[0011] In some embodiments, the pre-formulated etching solution includes the following components:

[0012] Sodium persulfate 100-105g / L

[0013] 98% sulfuric acid 10-12ml / L

[0014] Water balance.

[0015] In some embodiments, the electrodeposition method in step S400 is: based on a pre-configured electroplating solution, the foam nickel substrate is used as the cathode, and pure nickel and pure molybdenum with a mass ratio of 2-5:1 are used as a mixed anode for double-sided electroplating, the electroplating current density is 0.1-5ASD, the electroplating time is 20-60min, the electroplating solution temperature is 50-60°C, and the electroplating solution pH value is 8-9.

[0016] In some embodiments, the pre-configured electroplating solution includes the following components:

[0017]

[0018] In some embodiments, the method further includes step S500 of washing and drying the three-dimensional porous nickel-molybdenum alloy foam material.

[0019] In some embodiments, the drying process in step S500 is specifically as follows: the drying temperature is 50-60°C, the wind speed is 0.6±0.1m 3 / min, drying time is 1-3min.

[0020] The present application also provides an application of a three-dimensional porous nickel-molybdenum alloy foam material, wherein the three-dimensional porous nickel-molybdenum alloy foam material prepared by the above-mentioned three-dimensional porous nickel-molybdenum alloy foam material preparation method is applied to a water electrolysis hydrogen production electrode, thereby preparing a water electrolysis hydrogen production electrode.

[0021] Compared with the prior art, the present application provides a method for preparing a three-dimensional porous nickel-molybdenum alloy foam material and its application. The alloy material prepared by the method is a nickel-molybdenum alloy material with a three-dimensional porous structure, and its main component is a nickel-molybdenum alloy. Therefore, compared with the existing hydrogen production electrode materials, the price of the nickel-molybdenum material is lower, and the three-dimensional porous structure makes the alloy material have a higher porosity and specific surface area, which can make the hydrogen production electrode have more hydrogen evolution active sites and higher catalytic activity. The nickel-molybdenum alloy structure is stable and can maintain catalytic activity for a long time in an alkaline environment. Furthermore, the water electrolysis hydrogen production electrode obtained by the three-dimensional porous nickel-molybdenum alloy material prepared by the method for preparing the nickel-molybdenum alloy foam provided by the present application has the same beneficial technical effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0023] Figure 1 is a flow chart of a method for preparing a three-dimensional porous nickel-molybdenum alloy foam material in some embodiments of the present application,

[0024] Figure 2 is an electron microscope scanning image of the nickel-molybdenum alloy foam material prepared in Example 1 of the present application,

[0025] Figure 3 is the EDS component analysis spectrum of the nickel-molybdenum alloy foam material prepared in Example 1 of the present application,

[0026] Figure 4 : is a schematic diagram comparing the overpotential test of the three-dimensional porous nickel-molybdenum alloy foam material prepared in the present application with the commercially available three-dimensional porous nickel-molybdenum alloy material and the commercially available woven mesh Raney nickel material,

[0027] Figure 5 It is a schematic diagram of a constant current test comparison between the three-dimensional porous nickel-molybdenum alloy foam material prepared in the present application, the commercially available three-dimensional porous nickel-molybdenum alloy material, and the commercially available woven mesh Raney nickel material. DETAILED DESCRIPTION

[0028] "Scope" disclosed in the present application is limited in the form of lower limit and upper limit, and a given range is limited by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundary of a special range. The scope limited in this way can be including end values ​​or not including end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a scope. For example, if the scope of 60-120 and 80-110 is listed for a specific parameter, it is understood that the scope of 60-110 and 80-120 is also expected. In addition, if the minimum range values ​​1 and 2 are listed, and if the maximum range values ​​3, 4 and 5 are listed, the following scope can be all expected: 1-3, 1-4, 1-5, 2-3, 2-4 and 2-5. In the present application, unless otherwise specified, the numerical range "ab" represents the abbreviation of any real number combination between a and b, wherein a and b are real numbers. For example, the numerical range "0-5" means that all real numbers between "0-5" are listed in this document, and "0-5" is just an abbreviation of these numerical combinations. In addition, when a parameter is expressed as an integer ≥ 2, it is equivalent to disclosing that the parameter is, for example, an integer of 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, etc.

[0029] If there is no special explanation, the "include" and "comprising" mentioned in this application are open-ended or closed-ended. For example, the "include" and "comprising" may mean that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0030] If not specifically stated, in this application, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0031] refer to Figure 1 As shown, Figure 1 A flowchart showing a three-dimensional porous nickel-molybdenum alloy foam material and a preparation method thereof in some embodiments of the present application is shown. The three-dimensional porous nickel-molybdenum alloy foam material and a preparation method thereof provided in the embodiments of the present application include the following steps:

[0032] S100, selecting a foam nickel substrate and cleaning it;

[0033] In this step, a nickel foam substrate is first selected, and then the selected nickel foam substrate is immersed in a cleaning agent mixed with anhydrous ethanol and acetone, and is cleaned by ultrasonic wave. The number of pores per inch (PPI) of the nickel foam substrate is 90-130, and illustratively, it can be 90, 100, 110, 120, 130, etc.; the surface density of the nickel foam substrate is 380-780 g / m 2 , for example, may be 380 g / m 2 , 480g / m 2 , 580g / m 2 , 680g / m 2 , 780g / m 2 etc.; the thickness of the nickel foam substrate is 0.6-4mm, and illustratively, it can be 0.6mm, 1.6mm, 2.6mm, 3.6mm, 4mm, etc.; the ultrasonic cleaning time is 1-6min, and illustratively, it can be 1min, 2min, 3min, 4min, 5min, 6min, etc.; the ultrasonic power is 150-300W, and illustratively, it can be 150W, 200W, 250W, 300W, etc.

[0034] S200, nickel foam substrate after pickling activation and cleaning;

[0035] This step is specifically as follows: placing the nickel foam substrate after ultrasonic cleaning in dilute sulfuric acid with a volume fraction of 9-12%, thereby removing the oxidized portion of the surface of the nickel foam substrate, and the pickling activation time is 3-5 minutes. Specifically, the volume fraction of the dilute sulfuric acid can be any value between 9-12%, and illustratively, it can be 9%, 10%, 11%, 12%, etc. The pickling activation time can be any value between 3-5 minutes. Schematically, the etching time can be 3 minutes, 3.5 minutes, 4 minutes, 4.5 minutes, 5 minutes, etc.

[0036] S300, micro-etching the surface of the nickel foam substrate after pickling and activation;

[0037] In this step, an etching solution is first prepared, and then the prepared etching solution is used to etch the surface of the nickel foam substrate after pickling and activation at room temperature, thereby effectively removing the oxidized part of the surface of the nickel foam substrate, and the etching time is 5-15s; specifically, the etching time can be any value between 5-15s, and illustratively, the etching time can be 5s, 6s, 7s, 8s, 9s, 10s, 11s, 12s, 13s, 14s, 15s, etc.;

[0038] Among them, the pre-configured etching solution includes the following components:

[0039] Sodium persulfate 100-105g / L

[0040] 98% sulfuric acid 10-12ml / L

[0041] Water balance.

[0042] S400, electro-depositing the micro-etched nickel foam substrate to obtain a three-dimensional porous nickel-molybdenum alloy foam material for a water electrolysis hydrogen production electrode;

[0043] The specific steps are as follows: first, a plating solution is prepared, and then the nickel foam substrate is used as a cathode, pure nickel and pure molybdenum with a mass ratio of 2-5:1 are used as a mixed anode, and double-sided electroplating is performed based on the prepared plating solution to obtain a three-dimensional porous nickel-molybdenum alloy foam material.

[0044] The mass ratio of pure nickel to pure molybdenum may be any ratio between 2 and 5:1, for example, 5:1, 4:1, 3:1, 2:1, etc.

[0045] Wherein, the double-sided electroplating process conditions are: the electroplating current density is any value between 0.1-5ASD, and exemplarily, it can be 0.1ASD, 0.5ASD, 1ASD, 1.5ASD, 2ASD, 2.5ASD, 3ASD, 3.5ASD, 4ASD, 4.5ASD, 5ASD, etc.; the electroplating time is any value between 20-60min, and exemplarily, it can be 20min, 30min, 40min, 50min, 60min, etc.; the electroplating solution temperature is any value between 50-60°C, and exemplarily, it can be 50°C, 52°C, 54°C, 56°C, 58°C, 60°C, etc.; the electroplating solution pH value is any value between 8-9, and exemplarily, it can be 8, 8.2, 8.4, 8.6, 8.8, 9, etc.;

[0046] The configured electroplating solution includes the following components:

[0047]

[0048] In the above-mentioned embodiment, by cleaning, activating, etching and electrodepositing the selected nickel foam substrate, a nickel-molybdenum alloy foam material with a three-dimensional porous structure is obtained. Since the nickel-molybdenum alloy foam material has a stable structure, it can maintain catalytic activity for a long time in an alkaline environment; at the same time, the main components of the nickel-molybdenum alloy foam material are metal nickel and molybdenum, which are cheaper than the precious metals in the existing water electrolysis hydrogen production electrode materials; moreover, the nickel-molybdenum alloy foam material is a three-dimensional porous structure, so that the nickel-molybdenum alloy foam material has a higher porosity and specific surface area, which can make the hydrogen production electrode have more hydrogen evolution active sites, and then the catalytic activity is higher, the overpotential is smaller, and the current density of the electrolyzer can have a larger improvement space, which can greatly reduce energy consumption and reduce the production cost of the application end. Therefore, the three-dimensional porous nickel-molybdenum alloy foam material preparation method provided in this application has a wide range of application prospects.

[0049] In some embodiments, the method further includes step S500 of washing and drying the three-dimensional porous nickel-molybdenum alloy foam material.

[0050] In this embodiment, pure water is first used to wash the prepared three-dimensional porous nickel-molybdenum alloy foam material, and then the washed three-dimensional porous nickel alloy foam material is dried.

[0051] The specific drying process is as follows: the drying temperature is any value between 50-60°C, for example, it can be 50°C, 52°C, 54°C, 56°C, 58°C, 60°C, etc.; the wind speed is 0.6±0.1m 3 Any value between / min, for example, 0.5m 3 / min, 0.55m 3 / min、0.6m 3 / min, 0.65m 3 / min, 0.7m 3 / min, etc.; the drying time is any value between 1-3min, and illustratively, it can be 1min, 1.5min, 2min, 2.5min, 3min, etc.

[0052] The present application also provides an application of a three-dimensional porous nickel-molybdenum alloy foam material, specifically, applying the three-dimensional porous nickel-molybdenum alloy foam material prepared by the above-mentioned three-dimensional porous nickel-molybdenum alloy foam material preparation method to a water electrolysis hydrogen production electrode, thereby preparing a water electrolysis hydrogen production electrode, and performing water electrolysis hydrogen production activities based on the water electrolysis hydrogen production electrode to provide clean energy hydrogen for the earth.

[0053] Based on the description of the beneficial technical effects of the above-mentioned three-dimensional porous nickel-molybdenum alloy foam material preparation method, the three-dimensional porous nickel-molybdenum alloy foam prepared by this preparation method is applied to the water electrolysis hydrogen production electrode, and the obtained hydrogen production electrode has the same beneficial technical effects, which will not be repeated here.

[0054] In order to better illustrate the working principle and beneficial effects of the technical solution of the present application, a three-dimensional porous nickel-molybdenum alloy foam material is prepared based on the three-dimensional porous nickel-molybdenum alloy foam material and its preparation method provided by the present application, as follows:

[0055] Example 1

[0056] 1) Select a nickel foam substrate with a PPI of 90-130 and a surface density of 380-780 g / m 2 , the thickness of the nickel foam substrate is 0.6-4 mm; then the nickel foam substrate is immersed in a mixture of anhydrous ethanol and acetone, and then cleaned by ultrasonic wave, wherein the ultrasonic cleaning time is 1-6 min, and the ultrasonic power is 150-300 W;

[0057] 2) Activating the nickel foam substrate after ultrasonic cleaning in dilute sulfuric acid with a volume fraction of 9-12%, thereby removing the oxidized part on the surface of the nickel foam substrate, and the acid washing activation time is 3-5 minutes;

[0058] 3) preparing an etching solution, and then etching the surface of the nickel foam substrate after pickling and activation with the prepared etching solution at room temperature, thereby effectively removing the oxidized part of the surface of the nickel foam substrate, and the etching time is 5-15s, wherein the etching solution includes the following components:

[0059] Sodium persulfate 100-105g / L

[0060] 98% sulfuric acid 10-12ml / L

[0061] Water balance;

[0062] 4) preparing an electroplating solution, and then using the foamed nickel substrate as a cathode, and using pure nickel and pure molybdenum with a mass ratio of 2-5:1 as a mixed anode, and performing double-sided electroplating based on the prepared electroplating solution to obtain a three-dimensional porous foamed nickel-molybdenum alloy material, wherein the electroplating current density is 0.1-5ASD, the electroplating time is 20-60min, the electroplating solution temperature is 50-60°C, the electroplating solution pH value is 8-9, and the prepared electroplating solution includes the following components:

[0063]

[0064] 5) The obtained three-dimensional porous nickel-molybdenum alloy foam material is washed and dried to obtain a finished three-dimensional porous nickel-molybdenum alloy foam material.

[0065] Finally, the three-dimensional porous nickel-molybdenum alloy material prepared in Example 1 was subjected to electron microscope scanning analysis and EDS composition analysis. Figure 2 and Figure 3 The EDS component analysis results are shown in Table 1.

[0066] Table 1 EDS composition analysis results of the finished three-dimensional porous nickel-molybdenum alloy material in Example 1

[0067] element wt% Atomic Percent O 7.23 24.72 Ni 61.80 57.61 Mo 30.97 17.66 Total amount: 100.00 100.00

[0068] The three-dimensional porous nickel-molybdenum alloy foam material product prepared in Example 1 was subjected to overpotential test and constant current test respectively with a commercially available three-dimensional porous nickel-molybdenum alloy product (Comparative Example 1) and a commercially available woven mesh Raney nickel product (Comparative Example 2). The specific results are as follows: Figure 4 and Figure 5 As shown, Figure 4 and Figure 5 In the figure, line ① represents the test results of the commercially available three-dimensional porous nickel-molybdenum alloy product, line ② represents the test results of the commercially available woven mesh Raney nickel product, and line ③ represents the test results of the three-dimensional porous foam nickel-molybdenum alloy material product prepared in Example 1.

[0069] from Figure 2 It can be seen that under an electron scanning microscope, the rib surface of the three-dimensional porous nickel-molybdenum alloy foam material product prepared in Example 1 presents a relatively regular small peak shape, and the small peak shape further increases the specific surface area of ​​the foam metal material, providing more active sites for the process of hydrogen production by electrolysis of water; From Tables 1 and Figure 3 It can be seen that the composition of the three-dimensional porous foam nickel-molybdenum alloy material product prepared in Example 1 includes two metal elements, nickel and molybdenum, among which the atomic percentage of molybdenum is 17.66 and the atomic percentage of nickel is 57.61, which further indicates that the product prepared in Example 1 is a nickel-molybdenum alloy product.

[0070] from Figure 4 It can be seen that when the three-dimensional porous nickel-molybdenum alloy foam material product prepared in Example 1 is subjected to electrochemical LSV testing with commercially available electrode materials, the product prepared in Example 1 exhibits a lower overpotential.

[0071] from Figure 5It can be seen that when the constant current test is carried out under the same environment, although the overpotential of Comparative Example 1 (commercially available nickel-molybdenum alloy product) is low at the beginning, which is equivalent to the product prepared in Example 1, after a long period of operation, the overpotential of Comparative Example 1 (commercially available nickel-molybdenum alloy product) rises very obviously, and the voltage rises by 36mV, while the voltage of Example 1 only rises by 4mV, indicating that compared with the product prepared in Example 1, Comparative Example 1 (commercially available nickel-molybdenum alloy product) has poor stability; the voltage of Comparative Example 2 (commercially available woven mesh Raney nickel product) rises by 19mV. Although the stability is good, the overpotential of Comparative Example 2 (commercially available woven mesh Raney nickel product) is more than twice that of the product prepared in Example 1, and a higher overpotential means higher energy consumption.

[0072] In summary, the three-dimensional porous nickel-molybdenum alloy material product prepared in Example 1 mainly consists of nickel and molybdenum, and the product has a higher specific surface area, which enables the hydrogen production electrode to have more hydrogen evolution active sites and a smaller overpotential; at the same time, the product has better stability and lower energy consumption. Therefore, the method for preparing the three-dimensional porous nickel-molybdenum alloy foam material provided in this application has broad application prospects.

[0073] The above is a detailed introduction to a method for preparing a three-dimensional porous nickel-molybdenum alloy foam material and its application provided by the present application. Specific examples are used herein to illustrate the principles and implementation methods of the present application. The description of the above embodiments is only used to help understand the core idea of ​​the present application. It should be pointed out that for ordinary technicians in this technical field, without departing from the principles of the present application, several improvements and modifications can be made to the present application, and these improvements and modifications also fall within the scope of protection of the claims of the present application.

Claims

1. A method for preparing a three-dimensional porous nickel-molybdenum alloy foam material, characterized in that: The method comprises: S100, selecting a foam nickel substrate and cleaning it; S200, nickel foam substrate after pickling activation and cleaning; S300, micro-etching the surface of the nickel foam substrate after pickling and activation; S400, electroplating the micro-etched nickel foam substrate to obtain a three-dimensional porous nickel-molybdenum alloy foam material for an electrode for hydrogen production by electrolysis of water.

2. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 1, characterized in that: The step S100 specifically includes: selecting a nickel foam substrate, soaking the nickel foam substrate with anhydrous ethanol and acetone, and then performing ultrasonic cleaning, wherein the ultrasonic cleaning time is 1-6 minutes and the ultrasonic power is 150-300W.

3. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 2, characterized in that: The step S200 specifically includes: placing the foamed nickel substrate after ultrasonic cleaning in dilute sulfuric acid with a volume fraction of 9-12%, thereby removing the oxidized part on the surface of the foamed nickel substrate, and the acid washing activation time is 3-5 minutes.

4. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 3, characterized in that: The step S300 specifically includes: performing microscopic etching on the surface of the nickel foam substrate after pickling and activation based on a pre-configured etching solution at room temperature, and the etching time is 5-15s.

5. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 4, characterized in that: Pre-formulated etching solutions include the following components: Sodium persulfate 100-105g / L 98% sulfuric acid 10-12ml / L Water balance.

6. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 5, characterized in that: The electroplating method in step S400 is: based on a pre-configured electroplating solution, the foam nickel substrate is used as the cathode, and pure nickel and pure molybdenum with a mass ratio of 2-5:1 are used as a mixed anode for double-sided electroplating, the electroplating current density is 0.1-5ASD, the electroplating time is 20-60min, the electroplating solution temperature is 50-60°C, and the electroplating solution pH value is 8-9.

7. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 6, characterized in that: The pre-configured plating solution includes the following components:

8. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 7, characterized in that: The method further includes step S500 of washing and drying the three-dimensional porous nickel-molybdenum alloy foam material.

9. The method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to claim 8, characterized in that: The drying process in step S500 is as follows: the drying temperature is 50-60°C, the wind speed is 0.6±0.1m 3 / min, drying time is 1-3min.

10. An application of a three-dimensional porous nickel-molybdenum alloy foam material, characterized in that: The three-dimensional porous nickel-molybdenum alloy foam material prepared by the method for preparing the three-dimensional porous nickel-molybdenum alloy foam material according to any one of claims 1 to 9 is applied to a water electrolysis hydrogen production electrode to thereby prepare a water electrolysis hydrogen production electrode.

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