Preparation method of hydrogen production electrode material with porous nano laminated structure

Abstract

The invention provides a preparation method of a hydrogen production electrode material with a porous nano laminated structure, which comprises the following steps of: 1, sequentially cleaning and drying a metal matrix for later use; 2, nickel and silicon are deposited on the bottom layer metal substrate cleaned in the step 1 through a sputtering method, and a nickel-silicon doped surface layer is formed on the bottom layer metal substrate; step 3, placing the metal matrix doped with the surface layer in the step 2 in a pickling solution, and performing pickling to remove silicon in the surface layer so as to form an intermediate porous nickel layer on the bottom metal matrix; and 4, putting the metal matrix with the porous nickel layer obtained in the step 3 into a precursor solution, and growing a surface nano catalyst layer on the middle porous nickel layer in situ, so as to prepare the hydrogen production electrode material with the porous nano laminated structure. The electrode material with the laminated structure is formed by a plurality of catalytic elements which have a synergistic effect, active sites are increased, an activation potential barrier is reduced, the hydrogen production reaction rate is accelerated, and the energy consumption required by hydrogen production is reduced.

Description

Technical Field

[0001] This invention belongs to the field of electrolytic hydrogen production technology, specifically relating to the preparation method of porous nanolayered hydrogen production electrode materials and the electrode materials obtained therefrom. Background Technology

[0002] The environmental crisis has prompted humanity to extract energy from renewable sources such as solar, wind, and tidal energy, while simultaneously needing to store the energy generated for various uses, thus requiring energy storage materials. Hydrogen (H2), due to its high energy density, is considered one of the ideal energy carriers, and water electrolysis is a crucial pathway for producing hydrogen using green energy. The hydrogen evolution reaction (HER) occurs at the cathode; HER is a two-electron, three-element reaction and a vital half-reaction in water electrolysis devices, playing a crucial role in overall efficiency. Therefore, the selection of electrode materials for hydrogen production is a critical aspect.

[0003] Currently, hydrogen production electrode materials are prepared and optimized by depositing catalyst coatings on a substrate. Most of these methods involve using different metal salts as catalyst coatings or forming catalyst coatings with different morphologies to improve conductivity, hydrophilicity, chemical stability, and active site density. However, in electrodes prepared by this method, bubbles generated during hydrogen production are easily adsorbed onto the coating surface and cannot be desorbed or escaped in time, ultimately resulting in bubble potential. This leads to low utilization of active sites and affects catalytic efficiency.

[0004] To overcome the above problems, the preparation of high-efficiency hydrogen production electrode materials has become an urgent task. Summary of the Invention

[0005] This invention aims to address the shortcomings of the aforementioned technologies by providing a method for preparing a porous nanolayered hydrogen production electrode material that allows gas to easily and promptly detach from the active site, improves the utilization rate of the active site, accelerates the hydrogen production reaction rate, and reduces energy consumption.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] A method for preparing a porous nanolayered hydrogen production electrode material, characterized by comprising the following steps:

[0008] Step 1: Clean and dry the metal substrate sequentially for later use;

[0009] Step 2: Nickel and silicon are deposited on the bottom metal substrate cleaned in Step 1 using a sputtering method to form a nickel-silicon doped surface layer on it;

[0010] Step 3: Place the metal substrate with the doped surface layer from Step 2 into an acid pickling solution to remove silicon from the surface layer, thereby forming an intermediate porous nickel layer on the bottom metal substrate.

[0011] Step 4: Place the metal substrate with a porous nickel layer obtained in Step 3 in a precursor solution, and grow a surface nano-catalyst layer in situ on the intermediate porous nickel layer to prepare a porous nano-layered hydrogen production electrode material.

[0012] In step 1, the cleaning process involves sequentially using acetone, anhydrous ethanol, and deionized water to remove impurities from the surface of the metal substrate; or, to further remove impurities, the metal substrate is sequentially subjected to ultrasonic treatment in a 15% (w / w) HCl acidic solution, anhydrous ethanol, and deionized water; the metal substrate is a metal fiber felt substrate or a metal mesh substrate.

[0013] Preferably, the metal fiber felt matrix is ​​a nickel fiber felt matrix.

[0014] In step 2, the sputtering method employs magnetron sputtering.

[0015] In step 3, the pickling solution is a single HF acid solution or an acid solution mixed with HF and HNO3 or H2SO4, etc., and is then placed in deionized water and anhydrous ethanol, and sonicated 3 times each for 30 minutes each time, and then dried.

[0016] In step 4, the precursor solution is obtained by dissolving various metal salt ions in deionized water and then stirring.

[0017] The metal salt ion is two or more of nickel salt, cobalt salt, molybdenum salt and tungsten salt.

[0018] Furthermore, the concentrations of the nickel salt and cobalt salt are 1-16 g / L, and the concentrations of the molybdenum salt and tungsten salt are 10-38 g / L.

[0019] The precursor solution can be obtained by adding two or more of the above-mentioned nickel salt, molybdenum salt, cobalt salt, or tungsten salt to deionized water, first subjecting it to ultrasonic treatment for 10-30 minutes, and then stirring vigorously for 0.5-2 hours.

[0020] Furthermore, a metal substrate with a porous nickel layer is placed in a precursor solution and left to stand at 40-100℃ for 2-10 hours to grow a nano-catalyst layer in situ on the surface of the metal substrate.

[0021] The obtained porous nanolayered hydrogen production electrode material was dried at 50-70℃ for 2-10 hours.

[0022] A hydrogen production electrode material with a porous nanolayer structure obtained by the above-mentioned preparation method is provided. The electrode material has a layered structure, consisting of a bottom metal substrate, a middle porous nickel layer, and a surface nanocatalyst layer from bottom to top. The porous nickel layer is attached to the surface of the bottom metal substrate, and the catalyst layer is grown in situ on the surface of the porous nickel layer.

[0023] Preferably, the thickness of the porous nickel layer is 5-20 μm, and the thickness of the nanocatalyst layer is 0.1-10 μm.

[0024] The porous nanolayered hydrogen production electrode material of the present invention is used as a catalytic electrode for water electrolysis.

[0025] The beneficial effects of this invention are:

[0026] This invention yields a porous nanolayered hydrogen production electrode material by first preparing an intermediate porous nickel layer on a bottom metal substrate, and then growing a surface nanocatalyst layer in situ on the porous nickel layer. This layered structure consists of three parts, each with the following functions: 1. The bottom layer is the metal substrate, providing strong support for the intermediate porous nickel layer and the surface nanocatalyst layer; 2. The intermediate porous nickel layer increases the effective contact area between the metal substrate and the solution, facilitating the timely escape of gas from the active sites and providing multiple escape paths for gas discharge, thus improving the utilization rate of the active sites; 3. The outermost layer is the nanocatalyst layer, where the synergistic effect of multiple catalytic elements increases the number of active sites, lowers the activation barrier, and accelerates the hydrogen production reaction rate, thereby reducing the energy consumption required for hydrogen production.

[0027] Furthermore, during electrolysis, multiple gases accumulate to form bubbles during hydrogen or oxygen evolution. The generated gases need to escape from the electrode surface in a timely manner, otherwise they will occupy active sites and affect subsequent reactions. Moreover, the porous nanolayered structure of this invention provides a wide range of open channels that are very conducive to the rapid escape and discharge of gases, preventing the accumulation of bubbles from affecting catalytic performance. Attached Figure Description

[0028] Figure 1 This is a topographic diagram of Example 3.

[0029] Figure 2 This is an enlarged view of the morphology of Example 3. Detailed Implementation

[0030] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments and accompanying drawings. Furthermore, the embodiments described below are merely illustrative examples of some embodiments of the present invention, and not the entire scope of implementation. Therefore, based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without inventive effort are within the scope of protection of the present invention.

[0031] The method for preparing the porous nanolayered hydrogen generation electrode material of the present invention includes the following steps:

[0032] Step 1: Clean and dry the metal substrate sequentially for later use;

[0033] Step 2: Nickel and silicon are deposited on the underlying metal substrate using a sputtering method to form a nickel-silicon doped surface layer on it;

[0034] Step 3: Place the doped metal substrate in an acid pickling solution to remove silicon from the surface layer, thereby forming an intermediate porous nickel layer on the bottom metal substrate.

[0035] Step 4: Place the metal substrate with a porous nickel layer obtained in Step 3 in a precursor solution, and grow a surface nano-catalyst layer in situ on the intermediate porous nickel layer to prepare a porous nano-layered hydrogen production electrode material.

[0036] The resulting layered electrode material consists of, from bottom to top, a bottom metal substrate, an intermediate porous nickel layer, and a surface nano-catalyst layer. The porous nickel substrate is attached to the surface of the bottom metal substrate, and the catalyst layer is grown in situ on the surface of the porous nickel layer. The thickness of the porous nickel substrate is 5-20 μm, preferably 8-18 μm; the thickness of the nano-catalyst layer is 0.1-10 μm, preferably 1-8 μm.

[0037] It should be noted that the porous nanolayered hydrogen production electrode material obtained by this preparation method has a significantly increased specific surface area when used as a catalytic electrode due to its porous nanostructure. As is well known, a larger specific surface area means that there can be more active sites, which can accelerate the rate of the water electrolysis reaction (HER) and thus improve the electrolysis efficiency.

[0038] Furthermore, the porous nanolayered structure of the hydrogen production electrode material facilitates rapid transfer between reactants (such as water molecules) and products (such as hydrogen or oxygen), reducing diffusion limitations and improving reaction kinetics. This excellent mass transfer characteristic helps maintain efficient electrochemical reactions, especially at high current densities.

[0039] Furthermore, by constructing a porous nanolayered network of electrode materials, continuous electron conduction pathways can be formed within the electrode, ensuring effective electron transport from the catalyst to the current collector. This effectively reduces the reaction overpotential and improves energy conversion efficiency.

[0040] Regarding the porous nanolayered nanocatalyst layer, various metal salts (catalysts) enter the porous nickel structure in the middle layer, which allows the catalyst particles to be more evenly distributed on the substrate surface and penetrate into the porous structure. This not only increases the number of catalytic active sites per unit area, but also avoids the accumulation and waste of catalyst, thus improving the utilization efficiency of the material.

[0041] Compared to a dense and smooth electrode surface, the porous nanolayered structure endows the electrode material with better flexibility and resistance to deformation, especially exhibiting superior performance under thermal and mechanical stress during long-term operation. Furthermore, the porous structure can alleviate the stress caused by volume changes, reduce the risk of catalyst layer peeling, and extend the electrode's lifespan.

[0042] At this point, during the electrochemical hydrogen or oxygen evolution process, the generated gases need to escape and dissipate from the electrode surface in a timely manner; otherwise, they will occupy active sites, and multiple gases will accumulate to form bubbles, affecting subsequent reactions. The porous nanolayered structure provides a wide network of open channels, which facilitates the rapid escape and dissipation of gases, preventing bubble accumulation from affecting catalytic performance.

[0043] Because the porous nanolayered electrode material of this invention can improve catalyst utilization efficiency, the amount of catalyst used can be reduced without sacrificing performance, thereby lowering costs. At the same time, this design also facilitates the exploration and application of more low-cost transition metal catalysts, further promoting the commercialization of green hydrogen energy technologies.

[0044] In this embodiment, the metal substrate is first subjected to ultrasonic treatment for 20 minutes each in acetone, anhydrous ethanol, and deionized water, and then dried. Nickel and silicon are then used to form a nickel-silicon doped surface layer on the metal substrate by magnetron sputtering.

[0045] Preferably, the metal substrate with a nickel-silicon doped surface is placed in a 0.5 mol single HF acid solution or a 0.5 mol HF solution mixed with HNO3 or H2SO4 to remove silicon elements, and then placed in deionized water and anhydrous ethanol for ultrasonication three times each for 30 min each time and dried to obtain a metal substrate with a porous nickel layer.

[0046] It should be noted that the nickel-silicon doped surface layer prepared by sputtering has good adhesion. During the sputtering process, the atoms generated after the high-energy particles bombard the target material are deposited on the substrate with high kinetic energy, which helps to form a tight and strong bond.

[0047] Sputtering produces a uniform surface layer thickness on a substrate, maintaining good uniformity even on complex three-dimensional network structures. By adjusting sputtering parameters (such as power, pressure, and time), the composition of the thin film can be precisely controlled.

[0048] Compared to other methods of surface preparation, sputtering can typically be performed at lower temperatures, reducing the risk of damage to the heat-sensitive nickel material and allowing for the use of a wider range of substrate materials. Because the sputtering process is carried out in a vacuum environment, contamination from airborne impurities is avoided, resulting in high-purity nickel surfaces. Furthermore, sputtered surfaces exhibit good crystallinity and fewer defects, thus improving surface quality and performance. Moreover, sputtering is a dry process, eliminating the need for organic solvents or other hazardous chemicals, aligning with modern green manufacturing principles.

[0049] In addition, a precursor solution is obtained by dissolving multiple metal salts in deionized water; the metal salts include two or more of nickel salts, cobalt salts, molybdenum salts, and tungsten salts.

[0050] The concentrations of the nickel salt and cobalt salt are 1-16 g / L, and the concentrations of the molybdenum salt and tungsten salt are 10-38 g / L.

[0051] It should be noted that nickel salts, cobalt salts, molybdenum salts, and tungsten salts are all non-precious transition metal compounds. This can effectively reduce the cost of catalysts, reduce dependence on scarce and expensive precious metals, help alleviate resource shortages, improve the security and stability of the supply chain, and achieve economic efficiency.

[0052] In addition, the metal substrate is a metal felt substrate or a metal mesh substrate;

[0053] Preferably, the metal substrate is a nickel felt substrate or a nickel mesh substrate.

[0054] It should be noted that nickel-based metals typically possess high mechanical strength and excellent machinability, making them easy to process into electrode substrates of various shapes and sizes, suitable for diverse applications. Furthermore, the flexibility of nickel-based materials makes them suitable for constructing flexible electrodes or electrode structures with complex geometries. The easy formation of an oxide layer on the nickel surface helps enhance the bonding force between catalyst particles and the substrate, improving catalyst adhesion and stability, and reducing the risk of catalyst detachment.

[0055] Nickel-based materials have good compatibility with a variety of non-precious metal catalysts (such as cobalt, molybdenum, tungsten, etc.), and these catalysts can be uniformly distributed on the nickel matrix through methods such as co-sputtering to form a highly efficient composite catalytic system.

[0056] In addition, the nickel salt, molybdenum salt, cobalt salt, and tungsten salt can be added to deionized water and ultrasonically treated for 10-30 minutes, followed by vigorous stirring for 0.5-2 hours to obtain a precursor solution.

[0057] Furthermore, a metal substrate with a porous nickel base layer is placed in a precursor solution and left to stand at 40-100℃ for 2-10 hours to grow a nano-catalyst layer in situ on the porous nickel layer.

[0058] The material obtained in this way is dried at 50-70℃ for 2-10 hours to obtain a porous nanolayered hydrogen production material.

[0059] Example 1

[0060] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried. Then, the nickel-based fiber felt was ultrasonically treated in 15% HCl acidic solution, ethanol, and deionized water for 20 minutes each, and dried at 60°C.

[0061] First, start the vacuum pump of the sputtering device to reduce the gas pressure in the sputtering chamber to... The process involves applying a vacuum of Pa, then mounting the nickel and silicon targets onto the sputtering source, fixing the cleaned and dried nickel-based fiber felt onto the substrate support, and using a rotating stage to continuously rotate the electrode during the deposition process to ensure its stable position and maintain a distance of 3 cm from the target. Argon is used as the working gas, and the sputtering time is 5 min, resulting in a nickel-silicon doped nickel-based fiber felt surface layer with a thickness of 5 μm.

[0062] Nickel fiber felt with a nickel-silicon doped surface was placed in a 0.5 mol HF solution to remove silicon from the surface, resulting in a nickel fiber felt with a porous nickel layer.

[0063] The nickel salt and cobalt salt were each at a concentration of 1 g / L, and the molybdenum salt and tungsten salt were each at a concentration of 10 g / L. The mixture was then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0064] A nickel-based fiber felt with a porous nickel layer was placed in the aforementioned precursor solution and allowed to stand at 40°C for 2 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate. Then, it was dried at 60°C for 5 hours to obtain a porous nano-layered hydrogen production material 1 with a nano-catalyst layer thickness of 0.1 μm.

[0065] Example 2

[0066] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0067] The nickel-based fiber felt was then subjected to ultrasonic treatment for 20 minutes each in 15% HCl acid solution, ethanol, and deionized water, and then dried at 60°C.

[0068] Start the vacuum pump to reduce the gas pressure in the sputtering chamber to... Under a vacuum of Pa, nickel and silicon targets were mounted on the sputtering source, and the cleaned and dried nickel-based fiber felt was fixed on the substrate support. A rotating stage was used to make the electrode rotate continuously during the deposition process to ensure that its position was stable and kept 3 cm away from the target. Argon was used as the working gas and the sputtering time was 10 min to obtain a nickel-based fiber felt with a nickel-silicon surface layer with a thickness of 8 μm.

[0069] Nickel-based fiber felt with a nickel-silicon doped surface was placed in a 0.5 mol HF+H2SO4 solution to remove silicon from the surface, resulting in a porous nickel-layered nickel-based fiber felt.

[0070] The nickel and cobalt salts were each at a concentration of 4 g / L, and the molybdenum and tungsten salts were each at a concentration of 17 g / L. The mixture was then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0071] A nickel-based fiber felt with a porous nickel substrate was placed in a precursor solution and allowed to stand at 40°C for 4 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate. Then, it was dried at 60°C for 5 hours to obtain a porous nano-layered hydrogen production material 2 with a nano-catalyst layer thickness of 2 μm.

[0072] Example 3

[0073] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0074] The nickel-based fiber felt was then placed in a 15% (w / w) HCl acid solution, ethanol, and deionized water and ultrasonically treated for 20 minutes, and then dried at 60°C.

[0075] Start the vacuum pump to reduce the gas pressure in the sputtering chamber to... Under a vacuum of Pa, nickel and silicon targets were mounted on the sputtering source, respectively. The cleaned and dried nickel-based fiber felt was fixed on the substrate support. A rotating stage was used to make the electrode rotate continuously during the deposition process to ensure that its position was stable and kept 3 cm away from the target. Argon was used as the working gas, the sputtering time was 15 min, and the surface thickness was 10 μm.

[0076] Nickel-based fiber felt with a nickel-silicon doped surface was placed in a 0.5 mol HF+HNO3 solution to remove silicon from the surface, resulting in a nickel-based fiber felt with a porous nickel layer.

[0077] The nickel salt and cobalt salt were each at a concentration of 8 g / L, and the molybdenum salt and tungsten salt were each at a concentration of 24 g / L. They were then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0078] A nickel-based fiber felt with a porous nickel substrate was placed in a precursor solution and allowed to stand at 60°C for 5 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate. Then, it was dried at 60°C for 5 hours to obtain a porous nano-layered hydrogen production material 3 with a nano-catalyst layer thickness of 4 μm.

[0079] Example 4

[0080] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0081] The nickel-based fiber felt was then subjected to ultrasonic treatment for 20 minutes each in 15% HCl acid solution, ethanol, and deionized water, and then dried at 60°C.

[0082] Start the vacuum pump to reduce the gas pressure in the sputtering chamber to... Under a vacuum of Pa, nickel and silicon targets were mounted on the sputtering source, and cleaned and dried nickel-based fiber felt was fixed on the substrate support. A rotating stage was used to make the electrode rotate continuously during the deposition process to ensure that its position was stable and kept 3 cm away from the target. Argon was used as the working gas, the sputtering time was 20 min, and the surface thickness was 15 μm.

[0083] Nickel-based fiber felt with a nickel-silicon doped surface was placed in a 0.5 mol HF+HNO3 solution to remove silicon from the surface, resulting in a nickel-based fiber felt with a porous nickel base.

[0084] The nickel and cobalt salts were each at a concentration of 12 g / L, and the molybdenum and tungsten salts were each at a concentration of 31 g / L. The mixture was then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0085] A nickel-based fiber felt with a porous nickel substrate was placed in a precursor solution and allowed to stand at 80°C for 7 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate. Then it was dried at 60°C for 5 hours to obtain a porous nano-layered hydrogen production material 4 with a nano-catalyst layer thickness of 6 μm.

[0086] Example 5

[0087] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0088] The nickel-based fiber felt was then subjected to ultrasonic treatment for 20 minutes each in 15% HCl acid solution, ethanol, and deionized water, and then dried at 60°C.

[0089] Start the vacuum pump to reduce the gas pressure in the sputtering chamber to... Under a vacuum of Pa, nickel and silicon targets were mounted on the sputtering source, respectively. The cleaned and dried nickel-based fiber felt was fixed on the substrate support. A rotating stage was used to make the electrode rotate continuously during the deposition process to ensure that its position was stable and kept 3 cm away from the target. Argon was used as the working gas, the sputtering time was 25 min, and the surface thickness was 20 μm.

[0090] Nickel-based fiber felt with a nickel-silicon doped surface was placed in a 0.5 mol HF+HNO3 solution to remove silicon from the surface, resulting in a nickel-based fiber felt with a porous nickel base.

[0091] The nickel and cobalt salts were each at a concentration of 16 g / L, and the molybdenum and tungsten salts were each at a concentration of 38 g / L. The mixture was then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0092] A nickel-based fiber felt with a porous nickel layer was placed in a precursor solution and allowed to stand at 100°C for 10 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate. Then, it was dried at 60°C for 5 hours to obtain a porous nano-layered hydrogen production material 5 with a nano-catalyst layer thickness of 10 μm.

[0093] Comparative Example 1

[0094] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0095] The nickel-based fiber felt was then subjected to ultrasonic treatment for 20 minutes each in 15% HCl acid solution, ethanol, and deionized water, and then dried at 60°C.

[0096] Start the vacuum pump to reduce the gas pressure in the sputtering chamber to... Under a vacuum of Pa, nickel and silicon targets were mounted on the sputtering source, respectively. A cleaned and dried nickel-based fiber felt was fixed to a substrate support. A rotating stage was used to continuously rotate the electrode during deposition, ensuring its stable position and maintaining a 3 cm distance from the target. Argon was used as the working gas, the sputtering time was 25 minutes, and the surface layer thickness was 20 μm. The resulting material was used directly as the electrode material without any precursor solution treatment.

[0097] Comparative Example 2

[0098] The nickel-based fiber felt was ultrasonically treated in acetone, anhydrous ethanol, and deionized water for 20 minutes each, and then dried.

[0099] The nickel-based fiber felt was then subjected to ultrasonic treatment for 20 minutes each in a 15% acidic solution, ethanol, and deionized water, and then dried at 60°C.

[0100] The nickel and cobalt salts were each at a concentration of 8 g / L, and the molybdenum and tungsten salts were each at a concentration of 24 g / L. The mixture was then added to deionized water and sonicated for 15 min, followed by vigorous stirring for 1 h to obtain the precursor solution.

[0101] Nickel-based fiber felt was placed in a precursor solution and left to stand at 100°C for 10 hours to grow a nano-catalyst layer in situ on the surface of a metal substrate.

[0102] After drying at 60℃ for 5 hours, a porous nanolayered hydrogen production material 21 with a nanocatalyst layer thickness of 10 μm was obtained.

[0103] Compared with Examples 1-5 above, the electrode materials prepared in Comparative Examples 1-2 were obtained without undergoing the complete steps of the present invention. Furthermore, the overpotential of hydrogen evolution during water electrolysis was tested on the electrode materials of these examples and comparative examples, and the results are shown in Table 1.

[0104] Table 1. Electrolytic hydrogen overpotentials of Examples 1-5 and Comparative Examples 1-2

[0105] sample <![CDATA[At a current density of 300 mA / cm 2 hydrogen evolution overpotential]]> Example 1 244 Example 2 223 Example 3 206 Example 4 275 Example 5 327 Comparative Example 1 456 Comparative Example 2 437

[0106] As can be seen from the data in Table 1, the overpotentials of the electrode materials prepared in Examples 1-5 of this invention are significantly lower than those in Comparative Examples 1-2 during the electrolytic hydrogen reaction. Even though Example 5 has a relatively higher overpotential, it is still 100 mA / cm lower than that of Comparative Examples 1-2. 2 The above suggests that the porous nanolayered hydrogen production electrode structure prepared by this invention has the following advantages:

[0107] 1. The porous structure provides an ultra-high specific surface area, which can expose more hydrogen evolution active sites, allowing the reaction to be more complete and directly reducing the overpotential required for reaction initiation. The lower the overpotential, the less energy loss is generated in the hydrogen production process due to "overcoming the reaction energy barrier", which meets the application requirements of energy-saving electrode materials. Long-term use can significantly reduce the cost of hydrogen production.

[0108] 2. Nanostructures can shorten charge transport paths and reduce electron transfer resistance, resulting in faster catalytic reaction rates and enabling the hydrogen evolution reaction to be driven without higher applied voltage;

[0109] 3. While the orderly arrangement of the layered structure, the porous nature retains the internal space buffer of the material, reducing the structural collapse caused by volume changes during the reaction and ensuring stable catalytic performance;

[0110] 4. The porous nanolayered composite structure can be flexibly controlled, as can be seen from the examples: the data of Examples 1-3 are consistent and there are no large fluctuations. Even if the overpotential of Examples 4-5 rises slightly due to parameter adjustment, it can return to high efficiency performance by optimizing the structural parameters, indicating that the structural design has a strong optimization space. The composite structure can also facilitate electrolyte penetration and hydrogen desorption, avoid the accumulation of bubbles on the electrode surface and block the active sites, and ensure that the reaction continues to proceed efficiently.

[0111] On the other hand, the use of various transition metal catalysts in the porous nanolayered electrode material of the present invention has the following advantages:

[0112] 1. Transition metals possess high intrinsic catalytic activity and exhibit multiple variable valence states, facilitating the formation of active centers. The d orbitals of transition metals are not fully filled, readily forming various valence states such as +2, +3, and +4. These valence states allow them to form dynamic chemical bonds with reaction intermediates (e.g., OH⁻, OOH⁻, H⁺). This ensures moderate adsorption strength (avoiding excessive strength leading to intermediate retention or insufficient adsorption due to weakness) while simultaneously lowering the reaction energy barrier through valence state cycling (e.g., A²⁺↔A³⁺, B²⁺↔B³⁺).

[0113] 2. The d-band centers of transition metals are flexible. The d-band centers of transition metals can be precisely controlled through alloying, doping, and interaction with the support to match the adsorption energy of intermediates in the target reaction.

[0114] 3. The multi-component composite and synergistic effect of transition metals enhances catalytic activity. Transition metals can form various compounds such as alloys (e.g., FeNi, NiMo), and different transition metals can act synergistically—for example, in NiFe alloy catalysts, the high conductivity of Ni combines with the high catalytic activity of Fe to form an "electron transport-catalytic reaction" synergy, thereby increasing the reaction rate.

[0115] 4. Transition metals are low-cost and environmentally friendly, which also helps to explore and apply the use of more low-cost other transition metal catalysts.

[0116] Therefore, the hydrogen production electrode of the porous nanolayered electrode material of the present invention can further promote the commercialization of green hydrogen energy technology.

[0117] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the technical solution of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method for preparing a porous nanolayered hydrogen production electrode material, characterized in that, Includes the following steps: Step 1: Clean and dry the metal substrate sequentially for later use; Step 2: Nickel and silicon are deposited on the bottom metal substrate cleaned in Step 1 using a sputtering method to form a nickel-silicon doped surface layer on it; Step 3: Place the metal substrate with the doped surface layer from Step 2 into an acid pickling solution to remove silicon from the surface layer, thereby forming an intermediate porous nickel layer on the bottom metal substrate. Step 4: Place the metal substrate with a porous nickel layer obtained in Step 3 in a precursor solution, and grow a surface nano-catalyst layer in situ on the intermediate porous nickel layer to prepare a porous nano-layered hydrogen production electrode material.

2. The preparation method according to claim 1, characterized in that, In step 1, the cleaning process involves sequentially using acetone, anhydrous ethanol, and deionized water.

3. The preparation method according to claim 1, characterized in that, In step 1, the metal matrix is ​​a metal fiber felt matrix or a metal mesh matrix.

4. The preparation method according to claim 1, characterized in that, In step 2, the sputtering method employs magnetron sputtering.

5. The preparation method according to claim 1, characterized in that, In step 3, the pickling solution is a single HF acid solution or an acid solution of HF mixed with HNO3 or H2SO4.

6. The preparation method according to claim 1, characterized in that, In step 4, the precursor solution is obtained by dissolving various metal salt ions in deionized water and then stirring. The metal salt ions are two or more of nickel salts, cobalt salts, molybdenum salts, and tungsten salts. Furthermore, the concentrations of the nickel salt and cobalt salt are 1-16 g / L, and the concentrations of the molybdenum salt and tungsten salt are 10-38 g / L.

7. The preparation method according to claim 6, characterized in that, The metal substrate with a porous nickel layer is placed in a precursor solution and left to stand at 40-100℃ for 2-10 hours.

8. A hydrogen production electrode material with a porous nanolayer structure obtained by any one of the preparation methods of claims 1 to 7, wherein the electrode material is a layered structure, comprising, from bottom to top, a bottom metal substrate, an intermediate porous nickel layer, and a surface nanocatalyst layer, wherein the porous nickel layer is attached to the surface of the bottom metal substrate, and the catalyst layer is grown in situ on the surface of the porous nickel layer.

9. The porous nanolayered hydrogen production electrode material according to claim 8, characterized in that, The thickness of the porous nickel layer is 5-20 μm, and the thickness of the nanocatalyst layer is 0.1-10 μm.

10. A porous nanolayered hydrogen production electrode material obtained by any one of the preparation methods of claims 1 to 7, or the porous nanolayered hydrogen production electrode material of claim 8 or 9, is used as a catalytic electrode for water electrolysis.

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