Nickel alloy electrode and preparation method and application thereof

Abstract

The invention discloses a nickel alloy electrode and a preparation method and application thereof.The preparation method comprises the steps that a nickel current collector is placed in electroplating liquid to be electroplated so that a nickel alloy layer can be formed on the surface of the nickel current collector, the electroplating liquid comprises nickel salt, cobalt salt, chromium salt, ferrous salt and auxiliaries, the concentration of the nickel salt in the electroplating liquid is 85-115 g / L, and the concentration of the cobalt salt in the electroplating liquid is 80-100 g / L; the concentration of the cobalt salt in the electroplating solution is 15-25 g / L, the concentration of the chromium salt in the electroplating solution is 5-15 g / L, the concentration of the ferrous salt in the electroplating solution is 3-7 g / L, the atomic ratio of nickel in the nickel alloy layer to doped elements cobalt, chromium and iron is larger than or equal to 2.8, and the pH value of the electroplating solution is 3-5. The Co, Cr and Fe element doped nickel-based alloy layer is prepared by adopting an electroplating solution with a specific formula through an electro-deposition method, atomic-scale combination between a substrate and a catalyst layer is realized, and not only is the excellent interface bonding strength achieved, but also the good durability is achieved.

Description

Technical Field

[0001] This invention relates to the field of water electrolysis for hydrogen production technology, and more specifically, to a nickel alloy electrode, its preparation method, and its application. Background Technology

[0002] With the accelerated global transition to a cleaner energy structure, hydrogen energy, as a zero-carbon energy carrier, has received widespread attention. Water electrolysis for hydrogen production, due to its advantages such as wide availability of raw materials and high product purity, has become a key link connecting renewable energy and the hydrogen energy industry. Water electrolysis for hydrogen production is one of the important pathways for the large-scale consumption of renewable energy, with hydrogen produced using renewable energy-based water electrolysis defined as "green hydrogen." Currently, alkaline water electrolysis for hydrogen production equipment has become the most widely used technology in the field of electrolytic hydrogen production equipment due to its high cost-effectiveness. However, traditional alkaline water electrolysis for hydrogen production equipment generally uses Raney nickel as the electrode material, which suffers from low current density and severe shedding of active material during long-term operation. To effectively reduce the energy consumption of the water electrolysis for hydrogen production, it is urgent to reduce its hydrogen evolution overpotential and oxygen evolution overpotential. Although precious metals (such as ruthenium, iridium, platinum, palladium, rhodium, and gold) exhibit excellent catalytic activity, their high material cost makes large-scale application in the industrial production of alkaline water electrolysis for hydrogen production electrodes difficult. In contrast, nickel, as a commonly used catalytic material in alkaline water electrolysis hydrogen production equipment, not only has good resistance to alkaline corrosion but also excellent catalytic activity, thus becoming a key area of ​​research and development for electrode materials.

[0003] The nickel-cobalt-phosphorus alloy developed in patent CN119843309A significantly improves hydrogen evolution activity through ternary synergistic effects, while the nickel-molybdenum alloy proposed in CN116479458A lowers the hydrogen adsorption energy barrier through the electronic modulation effect of molybdenum. Addressing the oxygen evolution reaction bottleneck, CN117488357A employs a phosphorus / sulfur dual-anion-doped nickel-iron layered double hydroxide, effectively regulating the electronic structure of the metal sites. Regarding rare earth element modification, CN117661015A introduces cerium to form a nickel-cerium composite oxide, exhibiting a unique oxygen vacancy regulation mechanism. While these material innovations enhance intrinsic activity, the chemical stability of the multi-component components in strongly alkaline electroplating solutions still faces challenges.

[0004] Electrode structure design is trending from two-dimensional planar structures to three-dimensional porous architectures. The "mountain-like protrusions" structure constructed by CN119843309A exposes more active sites through geometric morphology design. The layered porous "wheat ear" structure prepared by CN114959768B using a dynamic hydrogen bubble template method combines a large specific surface area with rapid bubble release characteristics. The three-dimensional interconnected channel structure formed by CN116479458A through a dealloying strategy, and the magnetic field-induced nickel nanobead core-shell structure developed by CN109821539B, all embody the design concept of integrated structure and function. While these microstructural innovations increase the electrochemical active surface area, they are prone to structural collapse or active layer peeling in strong convection electrolysis environments.

[0005] In terms of preparation processes, two polarized development paths have emerged: one, such as the simplified process route adopted by CN118854351A, can obtain high-performance catalysts through constant potential deposition combined with air oxidation; the other, such as the multi-step complex process implemented by CN110158111B, requires precise control of the formation process of the core-shell structure. The application of special preparation technologies has also become a highlight. The magnetic field-assisted growth method used by CN109821539B, the dynamic hydrogen bubble template method used by CN114959768B, and the dealloying and electroplating composite process implemented by CN116479458A, although capable of obtaining materials with special morphologies, pose challenges to large-scale production due to the sensitivity of process parameters.

[0006] In terms of industrial applications, traditional Raney nickel electrodes, while inexpensive, suffer from the dual limitations of insufficient activity and short lifespan. Noble metal catalysts, despite their superior performance, are hampered by their high cost, limiting large-scale application. Existing technologies, while demonstrating good performance in laboratory settings, face challenges such as uneven distribution of active components and poor structural consistency during scale-up production. Particularly for multi-component alloys requiring precise control of elemental ratios, and for multi-level structural materials dependent on specific morphologies, process repeatability becomes a key bottleneck restricting industrialization.

[0007] In view of this, the present invention is proposed. Summary of the Invention

[0008] The purpose of this invention is to provide a nickel alloy electrode, its preparation method, and its application, so as to improve the above-mentioned technical problems.

[0009] This invention is implemented as follows: In a first aspect, the present invention provides a method for preparing a nickel alloy electrode, comprising: placing a nickel current collector in an electroplating solution for electroplating to form a nickel alloy layer on the surface of the nickel current collector, wherein the electroplating solution comprises nickel salt, cobalt salt, chromium salt, ferrous salt and additives, wherein the concentration of the nickel salt in the electroplating solution is 85~115 g / L, the concentration of the cobalt salt in the electroplating solution is 15~25 g / L, the concentration of the chromium salt in the electroplating solution is 5~15 g / L, the concentration of the ferrous salt in the electroplating solution is 3~7 g / L, and the atomic ratio of nickel to doping elements cobalt, chromium and iron in the nickel alloy layer is ≥2.8, and the pH value of the electroplating solution is 3~5.

[0010] In an optional embodiment, the nickel salt includes nickel sulfate and nickel chloride.

[0011] In an optional embodiment, the mass ratio of nickel sulfate to nickel chloride is (3~5):1, and the cobalt salt, the chromium salt, and the ferrous salt are all sulfates; or, the mass ratio of nickel sulfate to nickel chloride is 1:(3~5), and the cobalt salt, the chromium salt, and the ferrous salt are all chlorides.

[0012] In an optional embodiment, the adjuvant includes a buffer, a complexing agent, a stress reliever, and an anionic surfactant.

[0013] In an optional embodiment, the buffer is selected from at least one of boric acid, tartaric acid, citric acid, and aminosulfonic acid.

[0014] In an optional embodiment, the complexing agent is selected from at least one of potassium sodium tartrate, aminotriacetic acid, disodium EDTA, and sodium citrate.

[0015] In an optional embodiment, the stress reliever is selected from at least one of saccharin, benzenesulfonamide, and p-toluenesulfonamide.

[0016] In an optional embodiment, the anionic surfactant is selected from at least one of sodium dodecyl sulfate and sodium dodecylbenzene sulfonate.

[0017] In an optional embodiment, the electroplating solution comprises 70-90 g / L nickel sulfate (NiSO4·6H2O), 15-25 g / L nickel chloride (NiCl2·6H2O), 15-25 g / L cobalt sulfate (CoSO4·6H2O), 5-15 g / L chromium sulfate (Cr2(SO4)3), 4-6 g / L ferrous sulfate (FeSO4·7H2O), 50-70 g / L boric acid (H3BO3), 30-40 g / L sodium potassium tartrate (NaKC4H4O6), 0.5-1.5 g / L saccharin (C7H5O3NS), and sodium dodecyl sulfate (C 12 H 25SO4Na) 0.4~0.6g / L.

[0018] In an optional embodiment, the temperature of the electroplating solution is controlled to be 30°C to 50°C during electroplating.

[0019] In an optional embodiment, the nickel current collector is first degreased in an alkaline solution before electroplating, and then the oxide film is removed in a hydrochloric acid solution.

[0020] In an optional embodiment, the nickel current collector is a nickel mesh.

[0021] In an optional embodiment, the anode used for electroplating is a Pt sheet, the nickel current collector is the cathode, and the current density is 25 mA / cm². 2 ~35mA / cm 2 .

[0022] In an optional embodiment, during electroplating, the electroplating solution is stirred at a speed of 700-900 rpm for a time of 50-70 minutes.

[0023] In an optional embodiment, after electroplating, the electroplated nickel current collector electrode is first cleaned with deionized water, then cleaned with ethanol, and then vacuum dried. Preferably, the drying temperature is 70℃~90℃ and the drying time is 1.5h~2.5h.

[0024] Secondly, the present invention provides a nickel alloy electrode, which is prepared by the nickel alloy electrode preparation method described in any of the foregoing embodiments.

[0025] Thirdly, the present invention provides the application of the nickel alloy electrode as described in the foregoing embodiments in the electrolysis of water to produce hydrogen.

[0026] This invention offers the following advantages: A nickel-based alloy (NiCoCrFe) doped with Co, Cr, and Fe elements was prepared by electrodeposition using a specific electroplating solution. This alloy exhibits excellent electrocatalytic activity, significantly reducing the energy consumption of water electrolysis hydrogen production systems. The alloy composition is designed with strict control over the atomic ratio of nickel to doping elements (Co, Cr, Fe) to ensure long-term stable performance of the electrode in alkaline electroplating solutions. Furthermore, the NiCoCrFe catalytic layer is constructed on the surface of a nickel current collector substrate using electroplating, achieving atomic-level bonding between the substrate and the catalytic layer. This results in excellent interfacial bonding strength and good durability. Notably, this electrode material is completely free of precious metals such as Ru, Ir, Pt, Pd, Rh, and Au, significantly reducing material costs while demonstrating promising prospects for large-scale production, making it an ideal replacement for traditional Raney nickel catalysts. Attached Figure Description

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 Here is a SEM image of the nickel alloy electrode of Embodiment 1 of the present invention; Figure 2 This is a SEM image of the nickel alloy electrode of Embodiment 2 of the present invention; Figure 3 This is a SEM image of the nickel alloy electrode of Comparative Example 1 of the present invention. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer shall apply. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.

[0030] Various embodiments of the present invention may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible subranges and single numerical values ​​within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed subranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the range referred to.

[0031] In the description of this invention, the terms "comprising," "including," etc., mean "including but not limited to." In this document, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b, or c," or "at least one of a, b, and c," can both represent: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can each be single or multiple.

[0032] Some embodiments of the present invention provide a method for preparing a nickel alloy electrode, comprising: placing a nickel current collector in an electroplating solution for electroplating to form a nickel alloy layer on the surface of the nickel current collector, wherein the electroplating solution comprises nickel salt, cobalt salt, chromium salt, ferrous salt and additives, wherein the concentration of the nickel salt in the electroplating solution is 85~115 g / L, the concentration of the cobalt salt in the electroplating solution is 15~25 g / L, the concentration of the chromium salt in the electroplating solution is 5~15 g / L, the concentration of the ferrous salt in the electroplating solution is 3~7 g / L, and the atomic ratio of nickel to doping elements cobalt, chromium and iron in the nickel alloy layer is ≥2.8, and the pH value of the electroplating solution is 3~5.

[0033] By precisely controlling the composition ratio of metal salts in the electroplating solution to ensure that the atomic ratio of nickel to doping elements (cobalt, chromium, and iron) is strictly controlled above 2.8:1, and by limiting the pH range of the electroplating solution, a nickel alloy coating doped with cobalt, chromium, and iron was successfully prepared on the surface of the nickel current collector. This alloy coating not only exhibits excellent catalytic activity but also forms an atomic-level bond with the substrate, demonstrating outstanding bonding strength and effectively ensuring the long-term stability of the electrode in an alkaline electroplating environment. Furthermore, the nickel alloy electrode prepared by this method does not contain precious metals such as ruthenium, iridium, platinum, palladium, rhodium, and gold, significantly reducing material costs and possessing the potential for large-scale industrial production, making it an ideal alternative to Raney nickel.

[0034] It should be noted that in the embodiments of the present invention, the atomic ratio of nickel to doping elements (cobalt, chromium, iron) is strictly controlled to be greater than or equal to 2.8:1, mainly based on the following considerations: First, maintaining a high nickel content ensures that the electronic conduction of the alloy is still dominated by the metallic bonds of nickel, thereby maintaining the high conductivity of the nickel matrix and avoiding a significant increase in electrode internal resistance due to excessive doping elements. Second, the d-orbital electronic structure of nickel makes it more resistant to OH in the electroplating solution.- Nickel possesses moderate adsorption energy for molecules such as H₂O, which forms the basis for the active sites in catalytic reactions. Excessive doping will disrupt the crystal structure of nickel, reducing the number of active sites and consequently lowering the electrode's catalytic efficiency. Particularly noteworthy is that when the proportion of chromium atoms is too high, intermetallic compounds such as NiCr₂O₄ or brittle phases are easily formed. This leads to a sharp increase in coating hardness and a significant decrease in toughness, causing the electrode to easily crack and peel during charge-discharge cycles. Furthermore, since nickel has a similar atomic radius to cobalt / iron, controlling the atomic ratio of nickel to doping elements (cobalt, chromium, iron) above 2.8:1 is beneficial for forming a uniform face-centered cubic solid solution structure, thereby ensuring good mechanical stability of the coating and enabling it to adapt to volume changes in the electrode during cycling.

[0035] In some implementations, the atomic ratio of nickel to doping elements cobalt, chromium, and iron in the nickel alloy layer is controlled to be (2.8~6):1.

[0036] In some embodiments, the nickel salt includes nickel sulfate and nickel chloride. Specifically, the mass ratio of nickel sulfate to nickel chloride is (3~5):1, and the cobalt salt, chromium salt, and ferrous salt are all sulfates; or, the mass ratio of nickel sulfate to nickel chloride is 1:(3~5), and the cobalt salt, chromium salt, and ferrous salt are all chlorides.

[0037] In relatively simple anionic systems, Ni 2+ Co 2+ Fe 2+ Cr 3+ Co-deposition is achieved to avoid alloy composition inhomogeneity caused by preferential deposition of a single element. Nickel sulfate or nickel chloride serves as the main salt, providing the majority of the Ni. 2+ A mass ratio of primary nickel salt to secondary nickel salt (3~5):1 can create a suitable polarization environment, avoiding excessively high polarization leading to a slow deposition rate, or excessively low polarization leading to a rough coating.

[0038] In some embodiments, the additives include buffers, complexing agents, stress relievers, and anionic surfactants. The buffer is selected from at least one of boric acid, tartaric acid, citric acid, and aminosulfonic acid; the complexing agent is selected from at least one of potassium sodium tartrate, aminotriacetic acid, disodium EDTA, and sodium citrate; the stress reliever is selected from at least one of saccharin, benzenesulfonamide, and p-toluenesulfonamide; and the anionic surfactant is selected from at least one of sodium dodecyl sulfate and sodium dodecylbenzenesulfonate.

[0039] For example, the electroplating solution includes 70-90 g / L of nickel sulfate (NiSO4·6H2O), 15-25 g / L of nickel chloride (NiCl2·6H2O), 15-25 g / L of cobalt sulfate (CoSO4·6H2O), 5-15 g / L of chromium sulfate (Cr2(SO4)3), 4-6 g / L of ferrous sulfate (FeSO4·7H2O), 50-70 g / L of boric acid (H3BO3), 30-40 g / L of potassium sodium tartrate (NaKC4H4O6), 0.5-1.5 g / L of saccharin (C7H5O3NS), and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.4~0.6g / L.

[0040] Alternatively, the electroplating solution may include nickel sulfate (NiSO4·6H2O) 15~25 g / L, nickel chloride (NiCl2·6H2O) 70~90 g / L, cobalt chloride (CoCl2·6H2O) 15~25 g / L, chromium trichloride (CrCl3) 5~15 g / L, ferrous chloride (FeCl2·4H2O) 4~6 g / L, boric acid (H3BO3) 50~70 g / L, potassium sodium tartrate (NaKC4H4O6) 30~40 g / L, saccharin (C7H5O3NS) 0.5~1.5 g / L, and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.4~0.6g / L.

[0041] During electroplating, a hydrogen evolution side reaction occurs at the cathode, leading to a local pH increase in Ni. 2+ Co 2+ Fe 2+ At pH > 6, hydroxide precipitates such as Ni(OH)₂ and Fe(OH)₃ are easily formed, contaminating the plating bath, clogging the nickel mesh current collector, and causing pinholes and pitting in the plating layer. pH fluctuations also alter the complexation balance between the complexing agent and metal ions, leading to a shift in the co-deposition ratio of Ni and Co / Fe / Cr, resulting in uncontrolled alloy composition. The buffering effect of boric acid can stabilize the pH of the plating bath within ±0.2: when hydrogen evolution at the cathode causes a pH increase, the equilibrium shifts to the positive side, [B(OH)₄] - Absorb H + When the pH decreases due to anodic dissolution or the addition of acidic additives, the equilibrium shifts in the reverse direction, releasing H₂. + .

[0042] Sodium potassium tartrate primarily acts as a complexing agent to stabilize metal ions and achieve co-deposition. The tartrate ion contains multiple hydroxyl (-OH) and carboxyl (-COOH) groups, which can react with Ni. 2+ Cu 2+ Fe 2+ Cr 3+When chelates are formed, they can prevent the hydrolysis of metal ions (such as Ni). 2+ It can form Ni(OH)₂ precipitate and control the concentration of free metal ions through the dissociation equilibrium of the complex. In nickel alloy electroplating, potassium sodium tartrate can simultaneously complex Ni… 2+ By adjusting the reduction potentials of different doping ions and narrowing the potential difference, uniform co-deposition can be achieved, avoiding compositional inhomogeneity caused by preferential precipitation of a single element. In addition, tartrate ions can be adsorbed on highly active sites on the cathode surface (such as grain edges), inhibiting local over-deposition and preventing the formation of dendritic and rough coatings.

[0043] Saccharin molecules possess both a hydrophobic benzene ring and a hydrophilic sulfonyl imide group, enabling them to selectively adsorb onto microscopic protrusions on the cathode surface. These protrusions exhibit high current density and strong adsorption, hindering the reduction and deposition of metal ions and slowing protrusion growth. Conversely, recessed areas have low current density and weak adsorption, allowing for normal metal ion deposition. This process gradually fills microscopic surface defects, achieving a smooth coating. Furthermore, saccharin molecules adsorbed on the cathode surface increase the activation energy for metal ion reduction, resulting in a nucleation rate exceeding the growth rate and refining the grain size. This refined grain structure reduces grain boundary defects and porosity, improving the coating's corrosion resistance.

[0044] During electroplating, the hydrogen evolution side reaction on the cathode surface generates tiny hydrogen bubbles. If these bubbles adhere to the cathode surface, they hinder metal ion deposition, forming pinholes or pitting defects. Sodium dodecyl sulfate (SLS) molecules, with their hydrophobic alkyl chains and hydrophilic sulfonic acid groups, can adsorb at the gas-liquid interface, significantly reducing the surface tension of the plating solution. This reduced surface tension makes it difficult for hydrogen bubbles to adhere to the cathode surface, causing them to detach or break quickly, thus preventing pinholes caused by bubble retention. Furthermore, SLS enhances the wetting ability of the plating solution on the cathode surface, ensuring uniform coverage of the nickel mesh current collector's mesh openings and reducing plating defects or uneven thickness caused by poor wetting.

[0045] Furthermore, in some embodiments, during electroplating, the temperature of the electroplating solution is controlled at 30°C to 50°C, for example, 30°C, 35°C, 40°C, 45°C, or 50°C. Controlling the plating solution temperature within 30°C to 50°C balances process stability, coating performance, and production efficiency. This temperature range allows for precise optimization of alloy co-deposition behavior, microstructure, and electrode function by regulating electroplating thermodynamics (such as complex dissociation and ionic activity) and kinetics (such as ion diffusion and electrode reaction rate).

[0046] In some implementations, before electroplating, the nickel current collector is first degreased in an alkaline solution, and then the oxide film is removed in a hydrochloric acid solution. This pretreatment of degreasing and oxide film removal eliminates contaminants and oxide layers on the substrate surface, exposing a clean and active metal surface. This lays the foundation for uniform deposition, interfacial bonding, and long-term service stability in subsequent electroplating, thereby ensuring the adhesion between the plating layer and the substrate, avoiding plating defects, and improving the overall performance of the electrode.

[0047] In some embodiments, the electroplating uses a Pt sheet as the anode and a nickel current collector (e.g., a nickel mesh) as the cathode, with a current density of 25 mA / cm². 2 ~35mA / cm 2 For example, 25 mA / cm can be selected. 2 26 mA / cm 2 27 mA / cm 2 28mA / cm 2 29 mA / cm 2 30 mA / cm 2 31 mA / cm 2 32 mA / cm 2 33 mA / cm 2 34 mA / cm 2 Or 35 mA / cm 2 This current density can match the reduction rate of various metal ions, with minimal deviation in alloy composition, ensuring consistent electrode performance. It also helps refine grains, improve density and mechanical stability, enhance catalytic activity and cycle life, and allows for a moderate, defect-free deposition rate, making it suitable for large-scale industrial production. Furthermore, it facilitates gentle hydrogen evolution, protects the stability of the plating solution, and reduces production costs.

[0048] In some embodiments, during electroplating, the electroplating solution is stirred at a speed of 700-900 rpm. Stirring at a suitable speed can suppress concentration polarization, achieving uniform co-deposition of Ni with Co / Cr / Fe with minimal compositional deviation; it can also refine grains, improve coating density and mechanical stability, and prevent cracking and peeling; furthermore, it helps improve uniform / deep plating capabilities, adapts to nickel mesh, ensures uniform coating coverage, suppresses hydrogen evolution and defects, and protects the stability of the plating solution.

[0049] In some implementations, the electroplating time is 50 min to 70 min, such as 50 min, 55 min, 60 min, 65 min or 70 min.

[0050] In some embodiments, after electroplating, the electroplated nickel current collector electrode is first cleaned with deionized water, then cleaned with ethanol, and then vacuum dried. Preferably, the drying temperature is 70°C to 90°C, for example 80°C, and the drying time is 1.5h to 2.5h, for example 2h.

[0051] Furthermore, some embodiments of the present invention also provide a nickel alloy electrode, which is prepared by the nickel alloy electrode preparation method described in any of the foregoing embodiments.

[0052] Furthermore, some embodiments of the present invention also provide the application of the nickel alloy electrode as described in the foregoing embodiments in the electrolysis of water to produce hydrogen.

[0053] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0054] Example 1 This embodiment provides a method for preparing a nickel alloy electrode, which includes the following steps: (1) Preparation of electroplating solution: Nickel sulfate (NiSO4·6H2O) 80g / L, nickel chloride (NiCl2·6H2O) 20g / L, cobalt sulfate (CoSO4·6H2O) 20g / L, chromium sulfate (Cr2(SO4)3) 10g / L, ferrous sulfate (FeSO4·7H2O) 5g / L, boric acid (H3BO3) 60g / L, potassium sodium tartrate (NaKC4H4O6) 35g / L, saccharin (C7H5O3NS) 1g / L, and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.5 g / L.

[0055] (2) Substrate cleaning: The nickel mesh is first degreased in an alkaline solution, and then the oxide film is removed in a hydrochloric acid solution.

[0056] (3) Electroplating: The anode is a Pt sheet, the cathode is a nickel mesh, and the current density is 30 mA / cm². 2 The electroplating solution is stirred with a magnetic stirrer at a speed of 800 rpm. The electroplating duration is 60 min. During the electroplating process, the temperature of the electroplating solution is controlled within the range of 30~50℃, and the pH value is 3~5. The pH value is adjusted using hydrochloric acid and potassium hydroxide solution.

[0057] (4) Electrode cleaning and drying: After electroplating, the nickel mesh is first cleaned with deionized water, then cleaned with ethanol, and then dried in a vacuum drying oven at 80°C for 2 hours.

[0058] The nickel alloy electrode prepared in Example 1 was observed for its microstructure using scanning electron microscopy (SEM), and its SEM image is shown below. Figure 1 As shown.

[0059] The electrode composition of Example 1 was analyzed using scanning electron microscopy energy-dispersive X-ray spectroscopy, and its composition is shown in Table 1.

[0060] Table 1

[0061] Example 2 This embodiment provides a method for preparing a nickel alloy electrode, which includes the following steps: (1) Preparation of electroplating solution: Nickel sulfate (NiSO4·6H2O) 20g / L, nickel chloride (NiCl2·6H2O) 80g / L, cobalt chloride (CoCl2·6H2O) 20g / L, chromium trichloride (CrCl3) 10g / L, ferrous chloride (FeCl2·4H2O) 5g / L, boric acid (H3BO3) 60g / L, potassium sodium tartrate (NaKC4H4O6) 35g / L, saccharin (C7H5O3NS) 1g / L and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.5 g / L.

[0062] (2) Substrate cleaning: The nickel mesh is first degreased in an alkaline solution, and then the oxide film is removed in a hydrochloric acid solution.

[0063] (3) Electroplating: The anode is a Pt sheet, the cathode is a nickel mesh, and the current density is 30 mA / cm². 2 The electroplating solution is stirred with a magnetic stirrer at a speed of 800 rpm. The electroplating duration is 60 min. During the electroplating process, the temperature of the electroplating solution is controlled within the range of 30~50℃, and the pH value is 3~5. The pH value is adjusted using hydrochloric acid and potassium hydroxide solution.

[0064] (4) Electrode cleaning and drying: After electroplating, the nickel mesh is first cleaned with deionized water, then cleaned with ethanol, and then dried in a vacuum drying oven at 80°C for 2 hours.

[0065] The nickel alloy electrode prepared in Example 2 was observed for its microstructure using scanning electron microscopy (SEM), and its SEM image is shown below. Figure 2 As shown.

[0066] The electrode composition of Example 2 was analyzed using scanning electron microscopy energy dispersive spectroscopy line scanning, and its electrode composition is shown in Table 2.

[0067] Table 2

[0068] It should be noted that Ca ions may be impurity ions introduced during the sample cleaning process.

[0069] Comparative Example 1 This comparative example provides a method for preparing a nickel alloy electrode, which includes the following steps: The following additives are not specified in this process: nickel sulfate (NiSO4·6H2O) 80 g / L, nickel chloride (NiCl2·6H2O) 20 g / L, cobalt sulfate (CoSO4·6H2O) 20 g / L, chromium sulfate (Cr2(SO4)3) 10 g / L, and ferrous sulfate (FeSO4·7H2O) 5 g / L.

[0070] Electroplating: Pt sheet is used as the anode, nickel mesh is used as the cathode, and the current density is 80 mA / cm². 2 The electroplating solution is stirred with a magnetic stirrer at a speed of 800 rpm. The electroplating duration is 60 min. During the electroplating process, the temperature of the electroplating solution is controlled within the range of 30~50℃, and the pH value is 3~5. The pH value is adjusted using hydrochloric acid and potassium hydroxide solution.

[0071] The nickel alloy electrode prepared in Comparative Example 1 was observed for its microstructure using scanning electron microscopy (SEM), and its SEM image is shown below. Figure 3 As shown.

[0072] The electrode composition of Comparative Example 1 was analyzed using scanning electron microscopy energy dispersive spectroscopy (EDS), and its electrode composition is shown in Table 3.

[0073] Table 3

[0074] The comparative example did not contain the additives proposed in this application's process, and under high current density, the coating adhesion was poor, resulting in severe peeling. Ru may be an impurity introduced during the cleaning process.

[0075] In summary, this invention employs electroplating technology to prepare a nickel-based alloy electrode with the composition NiCoCrFe. By adjusting the atomic ratio of Ni to (Co, Cr, Fe) to ≥2.8:1, the electrode material exhibits a high nickel content, thus demonstrating excellent chemical stability in alkaline electroplating solutions. Experiments show that alloying modification of nickel with Co, Cr, and Fe elements can significantly enhance the electrocatalytic activity of the material and effectively reduce the energy consumption of the water electrolysis hydrogen production system. This technology achieves atomic-level bonding between the substrate and the catalyst layer through electrodeposition of a NiCoCrFe catalyst layer on the nickel mesh substrate surface, exhibiting not only excellent interfacial bonding strength but also good durability. Notably, this material system is completely free of precious metal elements such as Ru, Ir, Pt, Pd, Rh, and Au, significantly reducing material costs and possessing advantages for large-scale industrial production, making it an ideal alternative to traditional Raney nickel catalysts.

[0076] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for preparing a nickel alloy electrode, characterized in that, It includes: A nickel current collector is placed in an electroplating solution for electroplating to form a nickel alloy layer on the surface of the current collector. The electroplating solution includes nickel salt, cobalt salt, chromium salt, ferrous salt, and additives. The concentration of the nickel salt in the electroplating solution is 85~115 g / L, the concentration of the cobalt salt is 15~25 g / L, the concentration of the chromium salt is 5~15 g / L, the concentration of the ferrous salt is 3~7 g / L, and the atomic ratio of nickel to doping elements cobalt, chromium, and iron in the nickel alloy layer is ≥2.

8. The pH value of the electroplating solution is 3~5.

2. The method for preparing the nickel alloy electrode according to claim 1, characterized in that, The nickel salts include nickel sulfate and nickel chloride; The mass ratio of nickel sulfate to nickel chloride is (3~5):1, and the cobalt salt, the chromium salt and the ferrous salt are all sulfates; or, the mass ratio of nickel sulfate to nickel chloride is 1:(3~5), and the cobalt salt, the chromium salt and the ferrous salt are all chlorides.

3. The method for preparing the nickel alloy electrode according to claim 1 or 2, characterized in that, The additives include buffers, complexing agents, stress relievers, and anionic surfactants; Preferably, the buffer is selected from at least one of boric acid, tartaric acid, citric acid, and aminosulfonic acid; Preferably, the complexing agent is selected from at least one of potassium sodium tartrate, aminotriacetic acid, disodium EDTA, and sodium citrate; Preferably, the stress reliever is selected from at least one of saccharin, benzenesulfonamide, and p-toluenesulfonamide; Preferably, the anionic surfactant is selected from at least one of sodium dodecyl sulfate and sodium dodecylbenzene sulfonate.

4. The method for preparing the nickel alloy electrode according to claim 3, characterized in that, The electroplating solution comprises 70-90 g / L nickel sulfate (NiSO4·6H2O), 15-25 g / L nickel chloride (NiCl2·6H2O), 15-25 g / L cobalt sulfate (CoSO4·6H2O), 5-15 g / L chromium sulfate (Cr2(SO4)3), 4-6 g / L ferrous sulfate (FeSO4·7H2O), 50-70 g / L boric acid (H3BO3), 30-40 g / L sodium potassium tartrate (NaKC4H4O6), 0.5-1.5 g / L saccharin (C7H5O3NS), and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.4~0.6g / L; Alternatively, the electroplating solution comprises 15-25 g / L nickel sulfate (NiSO4·6H2O), 70-90 g / L nickel chloride (NiCl2·6H2O), 15-25 g / L cobalt chloride (CoCl2·6H2O), 5-15 g / L chromium trichloride (CrCl3), 4-6 g / L ferrous chloride (FeCl2·4H2O), 50-70 g / L boric acid (H3BO3), 30-40 g / L sodium potassium tartrate (NaKC4H4O6), 0.5-1.5 g / L saccharin (C7H5O3NS), and sodium dodecyl sulfate (C 12 H 25 SO4Na) 0.4~0.6g / L.

5. The method for preparing the nickel alloy electrode according to claim 4, characterized in that, During electroplating, the temperature of the electroplating solution should be controlled between 30℃ and 50℃.

6. The method for preparing the nickel alloy electrode according to claim 1, characterized in that, Before electroplating, the nickel current collector is first degreased in an alkaline solution, and then the oxide film is removed in a hydrochloric acid solution. And / or, the nickel current collector is a nickel mesh.

7. The method for preparing the nickel alloy electrode according to claim 1, characterized in that, The electroplating uses a Pt sheet as the anode and a nickel current collector as the cathode, with a current density of 25 mA / cm². 2 ~35mA / cm 2 ; And / or, during electroplating, the electroplating solution is stirred at a speed of 700~900 rpm for 50~70 min.

8. The method for preparing a nickel alloy electrode according to claim 1, characterized in that, After electroplating, the electroplated nickel current collector electrode is first cleaned with deionized water, then with ethanol, and then vacuum dried. Preferably, the drying temperature is 70℃~90℃ and the drying time is 1.5h~2.5h.

9. A nickel alloy electrode, characterized in that, It is prepared by the method for preparing nickel alloy electrodes according to any one of claims 1 to 7.

10. The application of the nickel alloy electrode as described in claim 9 in the electrolysis of water to produce hydrogen.

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