Preparation method of titanium-based water electrolysis hydrogen production electrode and titanium-based water electrolysis hydrogen production electrode

Abstract

The embodiment of the invention provides a preparation method of a titanium-based water electrolysis hydrogen production electrode and the titanium-based water electrolysis hydrogen production electrode, and relates to the technical field of water electrolysis hydrogen production, and the method comprises the steps that a titanium electrode base body serves as an anode and is put into a passivation solution for electrification treatment, and a passivation film is formed on the surface of the titanium electrode base body based on the anode passivation reaction; and preparing a catalytic active layer on the outer layer of the passive film formed on the surface of the titanium electrode substrate to obtain the titanium-based water electrolysis hydrogen production electrode. By applying the embodiment of the invention, the hydrogen embrittlement resistance and durability of the titanium-based water electrolysis hydrogen production electrode can be improved, and the service life of the titanium-based water electrolysis hydrogen production electrode can be prolonged.

Description

Technical Field

[0001] This application relates to the field of water electrolysis for hydrogen production technology, and in particular to a method for preparing a titanium-based water electrolysis hydrogen production electrode and the titanium-based water electrolysis hydrogen production electrode. Background Technology

[0002] Hydrogen energy is a clean and efficient secondary energy source, and the acquisition of green hydrogen is considered a key pathway to achieving carbon reduction goals. Water electrolysis is a core technology for producing green hydrogen. This technology involves passing direct current through an electrolyzer filled with electrolyte, causing water molecules to undergo electrochemical reactions, including hydrogen evolution and oxygen evolution, at the water electrolysis electrodes to produce hydrogen gas. The water electrolysis electrodes are the key components responsible for these electrochemical reactions within the electrolyzer; their performance and lifespan directly determine the efficiency and economics of the water electrolysis hydrogen production system.

[0003] Titanium is widely used as the matrix material for water electrolysis hydrogen production electrodes due to its excellent corrosion resistance, high mechanical strength, and good electrical conductivity. However, in practical applications, it has been found that titanium often faces severe hydrogen embrittlement problems in water electrolysis hydrogen production environments, especially on the cathode side. This means that titanium-based water electrolysis hydrogen production electrodes experience a decrease in toughness and the formation of microcracks in such environments. This hydrogen embrittlement problem ultimately leads to coating peeling and brittle fracture of the substrate during the water electrolysis hydrogen production process, causing premature electrode failure. Summary of the Invention

[0004] The purpose of this application is to provide a method for preparing a titanium-based water electrolysis hydrogen production electrode and the titanium-based water electrolysis hydrogen production electrode itself, so as to improve the hydrogen embrittlement resistance of the titanium-based water electrolysis hydrogen production electrode. The specific technical solution is as follows: In a first aspect, embodiments of this application provide a method for preparing a titanium-based water electrolysis hydrogen production electrode, comprising: A titanium electrode substrate is placed in a passivation solution as the anode and subjected to electrochemical treatment to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction. A catalytic active layer is prepared on the outer layer of the passivation film formed on the surface of the titanium electrode substrate to obtain a titanium-based water electrolysis hydrogen production electrode.

[0005] Optionally, before immersing the titanium electrode substrate as the anode in a passivation solution for electrochemical treatment, and before forming a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction, the method further includes: The titanium electrode substrate is immersed in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate; the initial hydrogen is the hydrogen element introduced during the manufacturing and processing of the titanium electrode substrate and remaining inside the titanium electrode substrate.

[0006] Optionally, before immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution, the method further includes: The surface of the titanium electrode substrate is sandblasted to increase its surface roughness. The aforementioned process of immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate includes: The titanium electrode substrate, after sandblasting, is immersed in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate.

[0007] Optionally, the passivation solution is a mixed aqueous solution containing potassium permanganate, sodium phosphate and sodium fluoride.

[0008] Optionally, the concentration of potassium permanganate in the mixed aqueous solution is 0.5 g / L-4 g / L, the concentration of sodium phosphate is 5 g / L-10 g / L, and the concentration of sodium fluoride is 10 g / L; the aforementioned process of placing the titanium electrode substrate as the anode in the passivation solution for electro-current treatment to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction includes: placing the titanium electrode substrate as the anode in the passivation solution and performing electro-current treatment for 3 to 10 minutes under a constant voltage of 20V-60V to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction.

[0009] Optionally, the alkaline washing and hydrogen removal solution is a first mixed aqueous solution containing sodium hydroxide and tetrasodium EDTA, or the alkaline washing and hydrogen removal solution is a second mixed aqueous solution containing potassium hydroxide and tetrasodium EDTA.

[0010] Optionally, the concentration of sodium hydroxide in the first mixed aqueous solution is 5wt%-20wt%, and the concentration of tetrasodium EDTA is 0.5wt%-1.0wt%; the concentration of potassium hydroxide in the second mixed aqueous solution is 5wt%-20wt%, and the concentration of tetrasodium EDTA is 0.5wt%-1.0wt%; the aforementioned immersion of the titanium electrode substrate in an alkaline washing and dehydrogenation solution to remove the initial hydrogen present in the titanium electrode substrate includes: immersing the titanium electrode substrate in an alkaline washing and dehydrogenation solution at a temperature of 60℃-90℃ for 2 hours-8 hours to remove the initial hydrogen present in the titanium electrode substrate.

[0011] Optionally, the abrasive used in the sandblasting process is white corundum or silicon carbide, and the abrasive particle size is 30-60 mesh; the surface roughness of the titanium electrode substrate after sandblasting is 3.0μm-6.0μm.

[0012] Optionally, the preparation of a catalytic active layer on the outer layer of the passivation film formed on the surface of the titanium electrode substrate includes: preparing a nickel coating on the outer layer of the passivation film on the surface of the titanium electrode substrate by plasma spraying, wherein the catalytic active layer is a nickel coating.

[0013] Secondly, embodiments of this application provide a titanium-based water electrolysis hydrogen production electrode, which is prepared based on the preparation method of the titanium-based water electrolysis hydrogen production electrode in the first aspect described above.

[0014] Beneficial effects of the embodiments in this application: The method for preparing a titanium-based water electrolysis hydrogen production electrode and the titanium-based water electrolysis hydrogen production electrode provided in this application embodiment first involves placing a titanium electrode substrate as the anode in a passivation solution for electrochemical treatment, thereby forming a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction. Then, a catalytic active layer is prepared on the outer layer of the passivation film formed on the surface of the titanium electrode substrate to obtain the titanium-based water electrolysis hydrogen production electrode. The passivation film formed on the surface of the titanium electrode substrate can block external hydrogen atoms during the service life of the titanium-based water electrolysis hydrogen production electrode, preventing external hydrogen atoms from penetrating into the interior of the titanium electrode substrate and causing hydrogen embrittlement. This improves the hydrogen embrittlement resistance and durability of the titanium-based water electrolysis hydrogen production electrode, extending its service life.

[0015] Of course, implementing any product or method of this application does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0017] Figure 1 A schematic flowchart illustrating a method for preparing a titanium-based water electrolysis hydrogen production electrode according to an embodiment of this application; Figure 2 This is a schematic diagram of another process for preparing the titanium-based water electrolysis hydrogen production electrode provided in the embodiments of this application; Figure 3 A cross-sectional microstructure diagram of comparative sample 1 provided in the embodiments of this application; Figure 4 A cross-sectional microstructure diagram of test sample 1 provided in the embodiments of this application; Figure 5 The test results of the weight loss of the bottom mesh of comparative sample 1 and test sample 1 provided in the embodiments of this application are shown in the figure. Figure 6 The test results of the coating retention rate of comparative sample 1 and test sample 1 provided for the embodiments of this application are shown in the figure. Figure 7 This is a schematic diagram of the potential-current density curves of comparative sample 1 and test sample 1 provided in the embodiments of this application. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the 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 skilled in the art based on this application are within the scope of protection of this application.

[0019] To overcome the hydrogen embrittlement problem faced by titanium-based water electrolysis hydrogen production electrodes in water electrolysis hydrogen production environments, this application provides a method for preparing a titanium-based water electrolysis hydrogen production electrode, see [link to relevant documentation]. Figure 1 The method specifically includes the following steps: Step S101: The titanium electrode substrate is placed as the anode in the passivation solution for electrochemical treatment, so as to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction.

[0020] Anodic passivation refers to the process by which a metal acting as the anode loses its ability to dissolve into the solution to varying degrees under the influence of an electric current. Specifically, anodic passivation involves the formation of a dense oxide film on the surface of the anode. This film covers the metal, preventing further oxidation and dissolution, but still maintains its electrical conductivity.

[0021] In this embodiment, by immersing the titanium electrode substrate as the anode in a passivation solution and subjecting it to an electric current, a dense and uniform oxide film can be generated on the surface of the titanium electrode substrate as a passivation film through an anodic passivation reaction. Furthermore, the purpose of preparing this passivation film on the surface of the titanium electrode substrate in this embodiment is to encapsulate the internal titanium electrode substrate, thereby preventing external hydrogen atoms from penetrating into the titanium electrode substrate.

[0022] Specifically, the inventors of this application discovered through analysis that one reason why titanium-based water electrolysis hydrogen production electrodes are prone to hydrogen embrittlement is that during the water electrolysis hydrogen production process, the hydrogen evolution reaction on the cathode side produces hydrogen atoms (H). When these hydrogen atoms penetrate into the titanium electrode substrate of the titanium-based water electrolysis hydrogen production electrode, they react with titanium to form brittle titanium hydride (TiH2), leading to a decrease in the toughness of the titanium electrode substrate and thus causing hydrogen embrittlement. In the traditional manufacturing process of titanium-based water electrolysis hydrogen production batteries, the titanium electrode substrate is generally sandblasted first, and then a nickel coating is directly thermally sprayed onto the titanium electrode substrate to prepare the titanium-based water electrolysis hydrogen production electrode. Although this process can ensure the initial bonding strength between the titanium electrode substrate and the nickel coating, it lacks an effective barrier to prevent external hydrogen from penetrating into the titanium electrode substrate. As a result, during the service of the titanium-based water electrolysis hydrogen production electrode, hydrogen generated during the hydrogen evolution reaction can penetrate into the interior of the titanium electrode substrate along the pores and gaps of the nickel coating, causing hydrogen embrittlement. In this embodiment, by preparing a passivation film on the surface of the titanium electrode substrate, it is equivalent to adding a protective barrier to the titanium electrode substrate, which can prevent the hydrogen network generated during the hydrogen evolution reaction from penetrating into the interior of the titanium electrode substrate.

[0023] Step S102: Prepare a catalytic active layer on the outer layer of the passivation film formed on the surface of the titanium electrode substrate to obtain a titanium-based water electrolysis hydrogen production electrode.

[0024] The catalytic active layer is used to play a catalytic and conductive role in the electrolysis of water to produce hydrogen. In one example, the catalytic active layer can be a nickel coating.

[0025] The titanium-based water electrolysis hydrogen production electrode prepared in this application embodiment ultimately exhibits a multilayer structure, including a titanium electrode substrate, a passivation film wrapped around the outer layer of the titanium electrode substrate, and a catalytic active layer further wrapped around the outer layer of the passivation film.

[0026] The titanium-based water electrolysis hydrogen production electrode prepared in this application embodiment can be used as an electrode in the water electrolysis hydrogen production process, for example, as a cathode in the water electrolysis hydrogen production process.

[0027] The method for preparing a titanium-based water electrolysis hydrogen production electrode provided in this application involves first immersing a titanium electrode substrate as the anode in a passivation solution and subjecting it to an electric current treatment. This forms a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction. Then, a catalytic active layer is prepared on the outer layer of the passivation film formed on the surface of the titanium electrode substrate, resulting in a titanium-based water electrolysis hydrogen production electrode. The passivation film formed on the surface of the titanium electrode substrate can block external hydrogen atoms during the service life of the titanium-based water electrolysis hydrogen production electrode, preventing external hydrogen atoms from penetrating into the interior of the titanium electrode substrate and causing hydrogen embrittlement. This improves the hydrogen embrittlement resistance and durability of the titanium-based water electrolysis hydrogen production electrode, extending its service life.

[0028] In one embodiment of this application, when the titanium electrode substrate is placed in the passivation solution as the anode for electrochemical treatment in step S101, the passivation solution used can be a mixed aqueous solution containing potassium permanganate, sodium phosphate and sodium fluoride.

[0029] In one example, the concentration of potassium permanganate in the mixed aqueous solution is 0.5 g / L to 4 g / L, the concentration of sodium phosphate is 5 g / L to 10 g / L, and the concentration of sodium fluoride is 10 g / L. When the titanium electrode substrate is immersed in this mixed aqueous solution for electrochemical treatment, a constant voltage mode can be used, with the voltage controlled between 20 V and 60 V, and the treatment time between 3 and 10 minutes.

[0030] In one embodiment of this application, when a nickel coating is prepared on the surface of a titanium electrode substrate as a catalytic active layer, an atmospheric plasma spraying process can be used to prepare the nickel coating.

[0031] In one example, during the preparation of a nickel coating on a titanium electrode substrate using atmospheric plasma spraying, hydrogen and argon can be used as the working gases. Nickel metal powder is then fed onto the titanium electrode substrate to form the nickel coating. Specifically, the spraying power can be set to 38kW-45kW, the argon flow rate to 40L / min, the hydrogen flow rate to 10L / min-15L / min, the powder feed rate to 40g / min, and the spraying distance to 100mm-150mm to ensure a firmly bonded and densely structured nickel coating. Experiments have shown that the thickness of the nickel coating formed using this process ranges from 20μm to 50μm.

[0032] Furthermore, in practical applications, besides the hydrogen atoms generated during the hydrogen evolution reaction permeating into the titanium electrode matrix of the titanium-based water electrolysis hydrogen production electrode, the titanium electrode matrix may also contain a certain amount of "initial hydrogen." Both of these different sources of hydrogen can be factors contributing to hydrogen embrittlement. Initial hydrogen refers to hydrogen elements already present within the titanium electrode matrix before it is put into use or service, such as hydrogen absorbed during the smelting and rolling processes of titanium. In the manufacturing process of the titanium-based water electrolysis hydrogen production electrode, high temperatures during processes such as sandblasting and spraying may exacerbate the diffusion and accumulation of initial hydrogen within the titanium electrode matrix, thus creating a potential source of hydrogen embrittlement.

[0033] In view of this, in one embodiment of this application, before placing the titanium electrode substrate as the anode into the passivation solution for electro-current treatment according to the aforementioned step S101, the titanium electrode substrate can be soaked in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate.

[0034] The purpose of soaking the titanium electrode substrate in an alkaline washing and hydrogen removal solution is to cause the initial hydrogen present in the titanium electrode substrate to overflow from the interior of the titanium electrode substrate, thereby eliminating the potential hydrogen embrittlement risk caused by the presence of "initial hydrogen" inside the titanium electrode substrate from the source.

[0035] In this embodiment, after immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution, a passivation film and a catalytic active layer are sequentially prepared on the outer layer of the titanium electrode substrate based on the aforementioned steps S101-S102 to obtain a titanium-based water electrolysis hydrogen production electrode. In the titanium-based water electrolysis hydrogen production electrode obtained based on this embodiment, on the one hand, the initial hydrogen present inside the titanium electrode substrate is removed by the alkaline washing and hydrogen removal solution; on the other hand, the passivation film prevents external hydrogen from penetrating into the interior of the titanium electrode substrate. This synergistic protection mechanism of "internal and external defense" prevents the presence of hydrogen atoms inside the titanium electrode substrate, thereby effectively preventing hydrogen embrittlement in the titanium-based water electrolysis hydrogen production electrode and improving its resistance to hydrogen embrittlement.

[0036] In one embodiment of this application, when immersing the titanium electrode substrate in an alkaline washing and dehydrogenation solution, the alkaline washing and dehydrogenation solution used can be a mixed aqueous solution containing sodium hydroxide and tetrasodium EDTA (Ethylene Diamine Tetraacetic Acid), or a mixed aqueous solution containing potassium hydroxide and tetrasodium EDTA.

[0037] In one example, when the alkaline washing and hydrogen removal solution is a mixed aqueous solution containing sodium hydroxide and EDTA, the concentration of sodium hydroxide can be 5wt%-20wt% and the concentration of tetrasodium EDTA salt can be 0.5wt%-1.0wt%; when the alkaline washing and hydrogen removal solution is a mixed aqueous solution containing potassium hydroxide and tetrasodium EDTA salt, the concentration of potassium hydroxide can be 5wt%-20wt% and the concentration of tetrasodium EDTA salt can be 0.5wt%-1.0wt%. Furthermore, during the immersion treatment of the titanium electrode substrate with the alkaline washing and hydrogen removal solution, the treatment temperature can be controlled at 60℃-90℃, and the treatment time at 2 hours-8 hours.

[0038] The purpose of immersing the titanium electrode substrate in the alkaline washing and hydrogen removal solution in this embodiment is to promote the full release of initial hydrogen absorbed into the titanium electrode substrate during historical processing through a high-temperature, high-alkaline environment, thereby eliminating the risk of hydrogen embrittlement at its source. Adding tetrasodium EDTA to the alkaline washing and hydrogen removal solution helps to complex surface impurities and enhances the hydrogen removal effect.

[0039] In one embodiment of this application, before immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution, the surface of the titanium electrode substrate can be sandblasted to increase the surface roughness of the titanium electrode substrate, and then the sandblasted titanium electrode substrate can be immersed in an alkaline washing and hydrogen removal solution.

[0040] In this embodiment, the surface of the titanium electrode substrate is first sandblasted, then immersed in an alkaline hydrogen removal solution, and finally a passivation film and a catalytic active layer are sequentially prepared on the outer layer of the titanium electrode substrate. This achieves two beneficial effects. First, sandblasting significantly increases the surface area of ​​the titanium electrode substrate, providing a good mechanical bonding basis for the subsequent catalytic active layer. Second, during the immersion treatment of the sandblasted titanium electrode substrate in the alkaline hydrogen removal solution, the initial hydrogen inside the titanium electrode substrate is more easily released due to the surface lattice distortion and activated fresh surface generated during the sandblasting process. This improves the thoroughness of removing initial hydrogen from the titanium electrode substrate and further reduces the risk of hydrogen embrittlement in the titanium-based water electrolysis hydrogen production electrode.

[0041] In one embodiment of this application, when the surface of the titanium electrode substrate is sandblasted, the surface roughness Ra (Arithmetic mean deviation of the profile) of the titanium electrode substrate after sandblasting can be controlled within 3.0 μm-6.0 μm.

[0042] In one example, the abrasive used in the sandblasting process can be white corundum or silicon carbide, and the abrasive roughness can be 30-60 mesh.

[0043] For ease of understanding, the following is a possible preparation process for the actual preparation of a titanium-based water electrolysis hydrogen production electrode based on the preparation methods provided in the above embodiments of this application. See also Figure 2 The preparation process includes the following steps: Step S201: Surface roughening: The titanium electrode substrate is sandblasted to obtain a roughened titanium electrode substrate.

[0044] Step S202: Alkaline washing to remove hydrogen: The roughened titanium electrode substrate is placed in an alkaline washing solution to remove hydrogen. After the washing is completed, the residual solution on the surface is rinsed off with deionized water to obtain the dehydrogenated titanium electrode substrate.

[0045] Step S203: Electrolytic passivation: Place the dehydrogenated titanium electrode substrate into a passivation solution tank, use the dehydrogenated titanium electrode substrate as the anode, turn on the electrolysis power supply, and perform electrolytic passivation treatment on the dehydrogenated titanium electrode substrate in constant voltage mode to form a passivation film on the surface of the titanium electrode substrate; after completion, turn off the electrolysis power supply, remove the titanium electrode substrate, rinse off the residual solution on the surface of the titanium electrode substrate with deionized water, and dry the surface of the titanium electrode substrate with clean compressed air.

[0046] Step S204: Coating preparation: The titanium electrode substrate with the passivation film is placed on a plasma spraying stage, and the surface of the titanium electrode substrate is sprayed based on the plasma spraying nickel coating process to obtain a titanium-based water electrolysis hydrogen production electrode.

[0047] The above steps are all involved in the foregoing embodiments of this application, and can be referred to the description above for details.

[0048] Compared with the traditional preparation process of titanium-based water electrolysis hydrogen production electrodes, the preparation process of steps S201-S204 above has the following advantages: Firstly, the above-mentioned preparation process innovatively introduces an alkaline washing and hydrogen removal step before coating preparation, which can actively and effectively remove the initial hydrogen inside the titanium electrode substrate, fundamentally reducing the initial risk of hydrogen embrittlement.

[0049] Secondly, the above-mentioned preparation process involves electrolytic passivation treatment of the dehydrogenated titanium electrode substrate, which constructs a dense passivation film barrier layer on the surface of the titanium electrode substrate. This effectively inhibits the penetration of external hydrogen during service, forming a double protection against both internal and external hydrogen embrittlement with the alkaline washing hydrogen removal step, greatly improving the hydrogen embrittlement resistance life of the titanium-based water electrolysis hydrogen production electrode.

[0050] Thirdly, the unique step of sandblasting followed by alkaline washing in the above-mentioned preparation process can generate a fresh surface with lattice distortion and activation during sandblasting, which is more conducive to hydrogen escape, while the alkaline solution environment further promotes the initial hydrogen evolution. Finally, spraying is performed on a clean, roughened titanium electrode substrate with a passivation layer, ensuring that the nickel coating has extremely high bonding strength.

[0051] Fourth, the above-mentioned preparation process has clear steps and is easy to implement for industrial production. It can significantly extend the service life of titanium-based water electrolysis hydrogen production electrodes in harsh environments, and has high economic value and promising prospects for promotion.

[0052] To demonstrate the technical effects achievable by the above embodiments of this application, this application provides three embodiments of the actual preparation process of the titanium-based water electrolysis hydrogen production electrode (process flow of the preparation method of the titanium-based water electrolysis hydrogen production electrode provided in this application) and three corresponding comparative examples (using conventional process flow). The weight loss of the bottom mesh, coating retention rate, and hydrogen evolution potential of the titanium-based water electrolysis hydrogen production electrodes prepared based on these three embodiments and three comparative examples were tested. The testing procedures for bottom mesh weight loss, coating retention rate, and hydrogen evolution potential used in this application are described below: The weightlessness of the bottom net was obtained through the following steps a1-a3: Step a1: Before conducting the electrolysis experiment on the titanium-based water electrolysis hydrogen production electrode, the prepared titanium-based water electrolysis hydrogen production electrode was ultrasonically cleaned to remove oil, and its surface was dried with dry compressed air. Then, it was placed in an oven and dried at 80°C for 2 hours. After being taken out, it was weighed and the initial weight of the titanium-based water electrolysis hydrogen production electrode was recorded.

[0053] Step a2: Conduct an electrolysis experiment on the prepared titanium-based water electrolysis hydrogen production electrode.

[0054] The electrolysis experiment can be carried out through the following experimental procedure: Prepare a standard alkaline electrolyte solution of 6 mol / L KOH (potassium hydroxide) or NaOH (sodium hydroxide) using deionized water. Before the experiment, purge the prepared electrolyte solution with high-purity argon gas for 15-30 minutes to remove oxygen, and maintain an inert gas atmosphere above the liquid surface. Use an electrochemical workstation for testing, connecting the reference electrode, auxiliary Pt (platinum) electrode, and bottom grid electrode (i.e., the titanium-based water electrolysis hydrogen production electrode being tested). Turn on the workstation and perform a rapid CV scan in the non-Radida region from the open circuit potential to the negative potential direction at a scan rate of 5 mV / s until the curve stabilizes. After the curve stabilizes, maintain a constant current density of 1 kA / m². 2 A continuous electrolysis experiment was conducted at (kA per square meter).

[0055] Furthermore, by analyzing the current-potential curves recorded for the titanium electrode hydrolysis hydrogen production electrode during the above-mentioned experimental process, the hydrogen evolution potential of the titanium electrode hydrolysis hydrogen production electrode can also be obtained.

[0056] Step a3: After the electrolysis experiment, rinse the surface of the titanium-based water electrolysis hydrogen production electrode with deionized water and dry it with dry compressed air. Then place it in an oven and set the baking temperature to 80℃ for 2 hours. After taking it out, weigh it again. The difference between the weight and the initial weight is the weight loss of the bottom mesh.

[0057] Coating retention rate was obtained through the following steps b1-b2: Step b1: Conduct an electrolysis experiment on the prepared titanium-based water electrolysis hydrogen production electrode.

[0058] For the procedure of the electrolysis experiment, please refer to the previous explanation of step a2.

[0059] Step b2: Select the most representative 100mm × 100mm test area on the surface of the titanium-based water electrolysis hydrogen production electrode after the electrolysis experiment, and prepare a metallographic photograph of the same scale. Place standard transparent grid paper on the metallographic photograph, count the number of grids occupied by the exposed substrate on the surface of the titanium-based water electrolysis hydrogen production electrode, and calculate the coating retention rate based on the following formula:

[0060] in, The number of grid cells occupied by the exposed substrate on the surface of a titanium-based water electrolysis hydrogen production electrode. This represents the total number of grid cells occupied by the measured area on the metallographic photograph.

[0061] As mentioned earlier, the hydrogen evolution potential of the titanium-based water electrolysis hydrogen production electrode can be determined by analyzing the recorded current-potential curves during the electrolysis experiment. In the embodiments and comparative examples of this application, a value of 1 kA / m is specifically used. 2 The threshold current density is used to determine the hydrogen evolution potential of a titanium-based water electrolysis hydrogen production battery.

[0062] The specific embodiments and comparative examples are described below: Example 1 In Example 1, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps d1-d4: Step d1: The titanium electrode substrate is sandblasted with 30-mesh white corundum abrasive to achieve a surface roughness Ra of 3.8 μm.

[0063] Step d2: Immerse the sandblasted titanium electrode substrate in an aqueous solution containing 10 wt% sodium hydroxide and 0.6 wt% tetrasodium EDTA, and dehydrogenate it at a constant temperature of 90°C for 6 hours. Rinse with deionized water after treatment.

[0064] Step d3: Using the dehydrogenated titanium electrode substrate as the anode, place it in an electrolyte containing 2 g / L potassium permanganate, 6 g / L sodium phosphate, and 10 g / L sodium fluoride, apply a 30 V DC voltage, and passivate for 5 minutes. After treatment, remove it, rinse with deionized water, and dry it.

[0065] Step d4: The passivated titanium electrode substrate is fixed on a plasma spraying device, and a nickel coating is prepared on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 40KW, the argon flow rate is 40L / min, the hydrogen flow rate is 12L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm. The final nickel coating thickness is 30μm.

[0066] For ease of explanation, the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps d1-d4 is designated as test sample 1.

[0067] Comparative Example 1

[0068] In Comparative Example 1, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps e1-e2: Step e1: The titanium electrode substrate is sandblasted with 30-mesh white corundum abrasive to achieve a surface roughness Ra of 3.8 μm.

[0069] Step e2: Fix the sandblasted titanium electrode substrate onto a plasma spraying equipment and prepare a nickel coating on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 40KW, the argon flow rate is 40L / min, the hydrogen flow rate is 12L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm.

[0070] It can be seen that the difference between Comparative Example 1 and Example 1 is that in Comparative Example 1, after sandblasting, a nickel coating was directly sprayed onto the surface of the titanium electrode substrate, without performing alkaline washing to remove hydrogen and electrolytic passivation treatment on the titanium electrode substrate.

[0071] For ease of explanation, the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps e1-e2 is referred to as Comparative Sample 1.

[0072] This application obtained cross-sectional microstructure diagrams of test sample 1 and control sample 1. The cross-sectional microstructure diagram of control sample 1 is shown below. Figure 3 See the cross-sectional microstructure diagram of test sample 1. Figure 4 It can be seen that, compared with the comparative sample 1 prepared based on the traditional process, the titanium electrode substrate and nickel coating in the test sample 1 prepared based on the process provided in the embodiments of this application are completely fused, and there is an effective hydrogen barrier (passivation film) at the fusion interface, which can prevent the titanium-based water electrolysis hydrogen production electrode from hydrogen embrittlement during service.

[0073] This application tested the weight loss of the bottom mesh of control sample 1 and test sample 1 based on the aforementioned steps a1-a3. The test results are as follows: Figure 5 As shown, the weight loss of the base mesh of control sample 1 was 1.7g, and the weight loss of the base mesh of test sample 1 was 1.3g. Furthermore, this application also tested the coating retention rate of control sample 1 and test sample 1 based on the aforementioned steps b1-b2, and the test results are as follows... Figure 6 As shown, the coating retention rate of control sample 1 was 95.03%, and the coating retention rate of test sample 1 was 97.01%. It can be seen that, within the same processing time, compared to control sample 1 prepared using a traditional process, test sample 1 prepared using the process provided in this application has less bottom mesh weight loss and a higher coating retention rate. This means that by applying the embodiments of this application to prepare titanium-based water electrolysis hydrogen production electrodes, the hydrogen embrittlement resistance and durability of the titanium-based water electrolysis hydrogen production electrodes can be significantly improved.

[0074] This application also recorded the current-potential curves of Comparative Sample 1 and Test Sample 1 during the electrolysis experiment (see step a2 above for the experimental procedure), and analyzed the hydrogen evolution potential of Comparative Sample 1 and Test Sample 1 based on the current-potential curves. The recorded results are shown in [link to relevant documentation]. Figure 7 The horizontal axis represents the electrode potential of the tested electrode (comparison sample 1, test sample 1) relative to the Hg / HgO reference electrode (vs Hg / HgO). The unit is V, and the vertical axis represents the current density J on the surface of the electrode being measured, with the unit being KA / m. 2 After the electrolysis curve stabilized, the hydrogen evolution potential of test sample 1 was -1.32V, while that of control sample 1 was -1.29V. The hydrogen evolution potential of test sample 1 did not change much compared to control sample 1, indicating that the titanium-based water electrolysis hydrogen production electrode prepared based on the process provided in this application has good hydrogen evolution stability.

[0075] Example 2

[0076] In Example 2, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps f1-f4: Step f1: The titanium electrode substrate is sandblasted with 30-mesh white corundum abrasive to achieve a surface roughness Ra of 3.0 μm.

[0077] Step f2: Immerse the sandblasted titanium electrode substrate in an aqueous solution containing 5 wt% sodium hydroxide and 0.5 wt% tetrasodium EDTA, and treat for hydrogen removal at a constant temperature of 60°C for 2 hours. Rinse with deionized water after treatment.

[0078] Step f3: Using the dehydrogenated titanium electrode substrate as the anode, place it in an electrolyte containing 0.5 g / L potassium permanganate, 5 g / L sodium phosphate, and 10 g / L sodium fluoride, apply a 20 V DC voltage, and passivate for 3 minutes. After treatment, remove it, rinse with deionized water, and dry it.

[0079] Step f4: The passivated titanium electrode substrate is fixed on a plasma spraying device, and a nickel coating is prepared on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 38KW, the argon flow rate is 40L / min, the hydrogen flow rate is 10L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm. The final nickel coating thickness is 20μm.

[0080] Comparative Example 2

[0081] In Comparative Example 2, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps g1-g2: Step g1: The titanium electrode substrate is sandblasted with 30-mesh white corundum abrasive to achieve a surface roughness Ra of 3.0 μm.

[0082] Step g2: Fix the sandblasted titanium electrode substrate onto a plasma spraying equipment, and prepare a nickel coating on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 38KW, the argon flow rate is 40L / min, the hydrogen flow rate is 10L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm.

[0083] For ease of explanation, the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps f1-f4 is designated as test sample 2, and the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps g1-g2 is designated as control sample 2.

[0084] Based on the aforementioned steps a1-a3, this application tested the weight loss of the base mesh of Comparative Sample 2 and Test Sample 2, finding that the weight loss of the base mesh of Comparative Sample 2 was 1.8g and that of Test Sample 2 was 1.6g. Furthermore, this application also tested the coating retention rate of Comparative Sample 2 and Test Sample 2 based on the aforementioned steps b1-b2, finding that the coating retention rate of Comparative Sample 2 was 94.73% and that of Test Sample 2 was 95.3%. It can be seen that, compared to Comparative Sample 2 prepared using the conventional process, Test Sample 2 prepared using the process of this application exhibits improved resistance to hydrogen embrittlement and enhanced durability.

[0085] In the electrolysis experiments conducted on Comparative Sample 2 and Test Sample 2, the current-potential curves of both samples were recorded, and the hydrogen evolution potential of Comparative Sample 2 and Test Sample 2 was analyzed based on the current-potential curves. The analysis showed that the hydrogen evolution potential of Comparative Sample 2 was -1.21V, and that of Test Sample 2 was -1.25V. The hydrogen evolution potential of Test Sample 2 did not change significantly compared to Comparative Sample 2, indicating that the titanium-based water electrolysis hydrogen production electrode prepared based on the process provided in this application has good hydrogen evolution stability.

[0086] Example 3

[0087] In Example 3, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps h1-h4: Step h1: The titanium electrode substrate is sandblasted with 60-mesh white corundum abrasive to achieve a surface roughness Ra of 6.0 μm.

[0088] Step h2: Immerse the sandblasted titanium electrode substrate in an aqueous solution containing 20 wt% sodium hydroxide and 1.0 wt% tetrasodium EDTA, and treat for hydrogen removal at a constant temperature of 90°C for 8 hours. Rinse with deionized water after treatment.

[0089] Step h3: Using the dehydrogenated titanium electrode substrate as the anode, place it in an electrolyte containing 4 g / L potassium permanganate, 10 g / L sodium phosphate, and 10 g / L sodium fluoride, apply a DC voltage of 60 V, and passivate for 10 minutes. After treatment, remove it, rinse with deionized water, and dry it.

[0090] Step h4: The passivated titanium electrode substrate is fixed on a plasma spraying device, and a nickel coating is prepared on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 45KW, the argon flow rate is 40L / min, the hydrogen flow rate is 15L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm. The final nickel coating thickness is 50μm.

[0091] Comparative Example 3

[0092] In Comparative Example 3, the titanium-based water electrolysis hydrogen production electrode was prepared through the following steps i1-i2: Step i1: The titanium electrode substrate is sandblasted with 60-mesh white corundum abrasive to achieve a surface roughness Ra of 6.0 μm.

[0093] Step i2: Fix the sandblasted titanium electrode substrate onto a plasma spraying equipment, and prepare a nickel coating on its surface using atmospheric plasma spraying. Argon and hydrogen are selected as the working gases, and nickel metal powder is used as the powder to be fed to the surface of the titanium electrode substrate. The spraying power is set to 45KW, the argon flow rate is 40L / min, the hydrogen flow rate is 15L / min, the powder feed rate is 40g / min, and the spraying distance is 100mm.

[0094] For ease of explanation, the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps h1-h4 is designated as test sample 3, and the titanium-based water electrolysis hydrogen production electrode prepared based on the above steps i1-i2 is designated as control sample 3.

[0095] Based on the aforementioned steps a1-a3, this application tested the weight loss of the base mesh of comparative sample 3 and test sample 3, finding that the weight loss of the base mesh of comparative sample 3 was 1.6g and that of test sample 3 was 1.5g. Furthermore, based on the aforementioned steps b1-b2, this application also tested the coating retention rate of comparative sample 3 and test sample 3, finding that the coating retention rate of comparative sample 3 was 94.87% and that of test sample 3 was 94.95%. It can be seen that, compared to comparative sample 3 prepared using a conventional process, test sample 3 prepared using the process of this application exhibits improved resistance to hydrogen embrittlement and enhanced durability.

[0096] In the electrolysis experiments conducted on Comparative Sample 3 and Test Sample 3, the current-potential curves of both samples were recorded, and the hydrogen evolution potential of Comparative Sample 3 and Test Sample 3 was analyzed based on the current-potential curves. The analysis showed that the hydrogen evolution potential of Comparative Sample 3 was -1.28V, and that of Test Sample 3 was -1.30V. The hydrogen evolution potential of Test Sample 3 did not change significantly compared to Comparative Sample 3, indicating that the titanium-based water electrolysis hydrogen production electrode prepared based on the process provided in this application has good hydrogen evolution stability.

[0097] Based on the same inventive concept, this application also provides a titanium-based water electrolysis hydrogen production electrode, which is prepared based on the preparation method of the titanium-based water electrolysis hydrogen production electrode provided in any of the foregoing embodiments.

[0098] For more information on the titanium-based water electrolysis hydrogen production electrode and its beneficial effects, please refer to the previous description of the preparation method of the titanium-based water electrolysis hydrogen production electrode.

[0099] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0100] The various embodiments in this specification are described in a related manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on its differences from other embodiments. In particular, the titanium-based water electrolysis hydrogen production electrode embodiment is basically similar to the method embodiment, so the description is relatively simple; relevant parts can be referred to the description of the method embodiment.

[0101] The above description is merely a preferred embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A method for preparing a titanium-based water electrolysis hydrogen production electrode, characterized in that, include: The titanium electrode substrate is placed in a passivation solution as the anode and subjected to an electric current treatment to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction. A catalytic active layer is prepared on the outer layer of the passivation film formed on the surface of the titanium electrode substrate to obtain a titanium-based water electrolysis hydrogen production electrode.

2. The method according to claim 1, characterized in that, The method further includes, prior to the formation of a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction, immersing the titanium electrode substrate as the anode in a passivation solution and subjecting it to electrochemical treatment. The titanium electrode substrate is immersed in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate; the initial hydrogen is hydrogen element introduced during the manufacturing and processing of the titanium electrode substrate and remaining inside the titanium electrode substrate.

3. The method according to claim 2, characterized in that, Before immersing the titanium electrode substrate in the alkaline washing and hydrogen removal solution, the method further includes: The surface of the titanium electrode substrate is sandblasted to increase the surface roughness of the titanium electrode substrate; The step of immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate includes: The titanium electrode substrate, after sandblasting, is immersed in the alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate.

4. The method according to claim 1, characterized in that, The passivation solution is a mixed aqueous solution containing potassium permanganate, sodium phosphate and sodium fluoride.

5. The method according to claim 4, characterized in that, The concentration of potassium permanganate in the mixed aqueous solution is 0.5 g / L-4 g / L, the concentration of sodium phosphate is 5 g / L-10 g / L, and the concentration of sodium fluoride is 10 g / L. The step of immersing a titanium electrode substrate as an anode in a passivation solution for electrochemical treatment, thereby forming a passivation film on the surface of the titanium electrode substrate based on an anodic passivation reaction, includes: The titanium electrode substrate is placed in the passivation solution as the anode and subjected to an energizing treatment at a constant voltage of 20V-60V for 3-10 minutes to form a passivation film on the surface of the titanium electrode substrate based on the anodic passivation reaction.

6. The method according to claim 2, characterized in that, The alkaline washing and hydrogen removal solution is a first mixed aqueous solution containing sodium hydroxide and tetrasodium EDTA, or the alkaline washing and hydrogen removal solution is a second mixed aqueous solution containing potassium hydroxide and tetrasodium EDTA.

7. The method according to claim 6, characterized in that, The concentration of sodium hydroxide in the first mixed aqueous solution is 5wt%-20wt%, and the concentration of tetrasodium EDTA is 0.5wt%-1.0wt%; the concentration of potassium hydroxide in the second mixed aqueous solution is 5wt%-20wt%, and the concentration of tetrasodium EDTA is 0.5wt%-1.0wt%. The step of immersing the titanium electrode substrate in an alkaline washing and hydrogen removal solution to remove the initial hydrogen present in the titanium electrode substrate includes: The titanium electrode substrate is immersed in an alkaline washing and hydrogen removal solution at a temperature of 60℃-90℃ for 2-8 hours to remove the initial hydrogen present in the titanium electrode substrate.

8. The method according to claim 3, characterized in that, The abrasive used in the sandblasting process is white corundum or silicon carbide, and the particle size of the abrasive is 30-60 mesh; the surface roughness of the titanium electrode substrate after sandblasting is 3.0μm-6.0μm.

9. The method according to claim 1, characterized in that, The preparation of a catalytic active layer on the outer layer of the passivation film formed on the surface of the titanium electrode substrate includes: A nickel coating is prepared on the outer layer of the passivation film on the surface of the titanium electrode substrate by plasma spraying, and the catalytic active layer is the nickel coating.

10. A titanium-based electrolytic water electrolysis electrode for hydrogen production, characterized in that, Prepared according to the method of any one of claims 1-9.

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