Porous multilayer nickel-tungsten alloy with high hydrogen evolution performance and preparation method thereof
By electroplating a porous, multi-layered nickel-tungsten alloy onto copper foam to form a three-dimensional porous structure, the problem of high cost of precious metal catalysts is solved, achieving a high hydrogen evolution performance and low cost water electrolysis hydrogen production process, which is suitable for industrial applications.
Patent Information
- Application Number
- CN202511282320.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-09
- Publication Date
- 2025-12-05
AI Technical Summary
In existing water electrolysis hydrogen production processes, the high cost of precious metal catalysts limits their industrial application, and the high consumption of HER and OER reactions necessitates reducing voltage and production costs.
Using copper foam as a substrate, a porous multilayer nickel-tungsten alloy is deposited on it by electroplating to form a three-dimensional porous structure, which increases the specific surface area and active sites, promotes electrolyte contact, reduces hydrogen bubble accumulation, and reduces polarization loss.
A nickel-tungsten alloy with high hydrogen evolution performance has been developed. It is low in cost, has high catalytic activity, is suitable for industrial applications, and reduces polarization loss and production costs.
Smart Images
Figure CN121065746A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of new energy materials technology, and relates to hydrogen evolution materials, specifically to a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance and its preparation method. Background Technology
[0002] With the urgent global need to reduce carbon emissions, hydrogen energy, due to its high energy density (142 MJ / kg) and zero carbon emissions, is considered a key energy carrier to replace fossil fuels. Currently, the main methods for producing hydrogen include water electrolysis (WE), methane steam reforming (SMR), coal steam (CG), and photocatalytic water splitting (WP). Among these, water electrolysis is one of the most efficient methods for obtaining high-purity hydrogen.
[0003] The water electrolysis reaction comprises two processes: the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER). Theoretically, the driving potential for water electrolysis is only around 1.23 V, but in practice, the required voltage often reaches 1.7 V or even higher. This is mainly because both HER and OER reactions are multi-step reactions involving multiple electrons and various intermediates, increasing energy consumption. To reduce consumption, electrocatalysts are typically used to enhance catalytic activity. In hydrogen electrolysis, noble metals such as Pt, Ru, and Ir can significantly reduce the overpotential of HER, making them excellent HER catalysts; however, their high cost limits their industrial application in water electrolysis for hydrogen production. Summary of the Invention
[0004] In view of the above-mentioned shortcomings of the existing technology, the purpose of this invention is to provide a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance and its preparation method. The porous multilayer nickel-tungsten alloy prepared by this invention has good electrocatalytic performance and low production cost, which is conducive to industrial application.
[0005] The technical solution of this invention is implemented as follows: A method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance involves using copper foam as the negative electrode and a carbon plate or steel plate as the positive electrode. Electroplating is performed in an electroplating bath at 60-80℃ for 1-10 minutes, thereby obtaining a porous multilayer nickel-tungsten alloy on the copper foam. The current density during electroplating is 3-10 A / cm². 2 .
[0006] Furthermore, the method for preparing the copper foam is as follows: The foam is placed in the vacuum chamber of a vacuum coating cleaving machine, then evacuated and filled with argon gas. Copper sheets with a purity of ≥99.9% are bombarded at 220-460V to deposit copper on the foam. The foam is then burned off to obtain foamed copper.
[0007] Furthermore, the electroplating solution is composed of the following components in the indicated mass percentages: nickel sulfate hexahydrate 1-15%, boric acid 1-15%, phosphate 1-15%, tungstate 1-15%, citric acid 1-15%, alkali 1-10%, and the remainder being deionized water.
[0008] Furthermore, the phosphate is one or more of sodium dihydrogen phosphate, sodium phosphate, ammonium dihydrogen phosphate, and ammonium phosphate.
[0009] Furthermore, the tungstate is one or more of sodium tungstate, potassium tungstate, and ammonium tungstate.
[0010] Furthermore, the alkali is one or more of sodium hydroxide, ammonia, and potassium hydroxide.
[0011] Furthermore, the pH of the electroplating solution is 6-10.
[0012] Furthermore, the current density is 3-5 A / cm². 2 .
[0013] Furthermore, the temperature of the electroplating solution is 65-75℃.
[0014] The present invention also provides a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance, which is prepared by the aforementioned method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance.
[0015] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention uses copper foam as a substrate and electroplating deposits a porous multilayer nickel-tungsten alloy on the copper foam. The nickel-tungsten alloy of this invention has a three-dimensional porous multilayer structure, which can effectively improve the specific surface area of the nickel-tungsten alloy, increase the number of active sites, promote the contact between the electrolyte and the electrocatalyst, and the porous structure is conducive to the rapid desorption of bubbles, reducing the accumulation of hydrogen bubbles on the electrode surface, reducing polarization loss, and exhibiting excellent electrocatalytic performance.
[0016] 2. The preparation method of the present invention for nickel-tungsten alloy has low production cost and is conducive to industrial application. Attached Figure Description
[0017] Figure 1 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Example 1.
[0018] Figure 2 - Macroscopic photographs of the foamed copper and porous multilayer nickel-tungsten alloys prepared in Example 1.
[0019] Figure 3 - Energy dispersive spectroscopy (EDS) analysis of the porous multilayer nickel-tungsten alloy prepared in Example 1.
[0020] Figure 4 - Tafel curve of the porous multilayer nickel-tungsten alloy prepared in Example 1.
[0021] Figure 5 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Example 2.
[0022] Figure 6 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Example 3.
[0023] Figure 7 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Comparative Example 1.
[0024] Figure 8 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Comparative Example 2.
[0025] Figure 9 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Comparative Example 3. Figure 10 - Scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in Comparative Example 4. Detailed Implementation
[0026] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.
[0027] Example 1 A method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance: (a) Preparation of copper foam, the preparation steps are as follows: (1) Select a specific surface area of 460 cm² 2 / g of foam, for later use.
[0028] (2) Place the foam in the vacuum chamber of the vacuum coating machine, then evacuate the vacuum, then fill it with argon gas, pass a high voltage current to make the argon gas glow discharge and ionize into argon ions and electrons, and turn on the water cooling at the same time.
[0029] (3) Argon ions will accelerate and bombard the cathode target (copper sheet with a purity of 99.9%) under the action of electric field. The target will be sputtered out and deposited on the foam surface.
[0030] (4) After deposition, the foam is burned off by processing at 300°C, and the metal is retained to obtain foamed copper.
[0031] (II) The nickel-tungsten alloy electroplating solution of this embodiment is composed of the following components in the indicated mass percentages: nickel sulfate hexahydrate 2%, boric acid 2%, sodium dihydrogen phosphate 2.5%, sodium tungstate 4%, citric acid 4.5%, ammonia 10%, and the remainder being deionized water. Its preparation method is as follows: (1) Prepare each component according to the aforementioned nickel-tungsten alloy electroplating solution composition; the deionized water is divided into three parts, the first part is 30% of the total mass of deionized water, the second part is 30% of the total mass of deionized water, and the remainder constitutes the third part.
[0032] (2) Add nickel sulfate hexahydrate to boric acid while stirring. After adding all the solution, stir for 10 minutes and then add the first portion of deionized water. Stir until homogeneous to obtain solution I.
[0033] (3) Slowly add sodium tungstate to sodium dihydrogen phosphate while stirring. After adding all the sodium tungstate, stir for 5 minutes. After stirring evenly, add the second portion of deionized water to obtain solution II.
[0034] (4) Slowly add solution I to solution II while stirring, then add citric acid and the third part of water in sequence, and finally add ammonia to adjust the pH value to 7. Stir evenly to obtain nickel-tungsten alloy electroplating solution.
[0035] (III) Electroplating a porous, multi-layered nickel-tungsten alloy onto the foamed copper, the specific steps of which are as follows: (1) Copper foam is used as the negative electrode, and the steel plate is used as the positive electrode; the electroplating solution is kept at a constant temperature of 65°C using a water bath heating method, and an electric current is passed through at a current density of 5A / cm². 2 The plating solution should be green. Turn on the DC power for 5 minutes.
[0036] (2) Turn off the current and dry in an 80°C drying oven for 30 minutes to obtain a porous multilayer nickel-tungsten alloy.
[0037] 1. In this embodiment, the weight of the copper foam is 0.0260g. After electroplating, the weight of the copper-based nickel-tungsten foam is 0.1009g, indicating that a total of 0.0749g of nickel-tungsten alloy was deposited. Scanning electron microscope images of the porous multilayer nickel-tungsten alloy prepared in this embodiment at different magnifications are shown below. Figure 1 As shown, by Figure 1 As can be seen, the prepared copper-based nickel-tungsten foam exhibits a three-dimensional porous multilayer structure. The surface of the copper foam is covered with a porous, multilayered nickel-tungsten alloy. This three-dimensional porous multilayer structure is beneficial for increasing the specific surface area, increasing the number of active sites, promoting the contact between the electrolyte and the electrocatalyst, and facilitating rapid bubble desorption, reducing hydrogen bubble accumulation on the electrode surface, and lowering polarization loss. Macroscopic photographs of the copper foam and the porous, multilayered nickel-tungsten alloy prepared in this embodiment are shown below. Figure 2 As shown, the upper part is foamed copper, and the lower part is a porous multilayer nickel-tungsten alloy.
[0038] 2. The energy dispersive spectroscopy (EDS) analysis diagram of the porous multilayer nickel-tungsten alloy prepared in this embodiment is shown below. Figure 3 As shown, its elemental composition is shown in the table below: Elt. Conc Units Ni 27.666 wt.% W 72.334 wt.% 100.000 wt.% Depend on Figure 3As shown in the table above, nickel and tungsten together comprise 100% of the coating composition, indicating that the coating is a nickel-tungsten alloy. Nickel accounts for 27.666% of the coating mass, while tungsten accounts for 72.334%. Based on the molar ratio converted from relative atomic masses, the W:Ni molar ratio is calculated to be 1:1.2. At this molar ratio, the nickel-tungsten alloy exhibits the high electrical conductivity of metallic Ni, ensuring rapid electron transport. Furthermore, this molar ratio of nickel-tungsten alloy overcomes the passivation problem of Ni(OH)₂ in alkaline environments, maintaining high activity.
[0039] 3. The porous multilayer nickel-tungsten alloy prepared in this example was encapsulated in resin to form an electrode (Al2O3 is required). This electrode was then placed in a 1M NaOH solution to form a circuit with a reference electrode and a platinum electrode. The solution was measured using steady-state current curve analysis in an electrochemical workstation, with a scan range of ±200 mV and a scan rate of 0.1–1 mV / s. The resulting Tafel curves are shown below. Figure 4 As shown in the figure, the hydrogen evolution efficiency of the three electrocatalysts increases with increasing current density, and the hydrogen evolution performance of the porous multilayer nickel-tungsten alloy prepared in this embodiment is far superior to that of iron.
[0040] The lower the slope (b), the faster the current density increases with the overpotential, the higher the charge transfer efficiency of the catalyst, and the more favorable the reaction kinetics. i 0 This represents the intrinsic reaction rate at the equilibrium potential (overpotential is 0). i 0 The higher the value, the higher the intrinsic activity of the catalyst. As shown in the table above: Tafel slope (b value): Ni-W 112 mV dec⁻¹, better than Fe (142), better than Pt (143), while Ni-W's... i 0 The activity of Ni-W is significantly higher than that of Fe, further demonstrating that the intrinsic activity of Ni-W is higher than that of Fe.
[0041] Example 2 This embodiment is the same as Embodiment 1, except that in this embodiment, the current is 3A / cm when electroplating a porous, multi-layered nickel-tungsten alloy onto the foamed copper. 2 .
[0042] The scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in this embodiment is shown below. Figure 5 As shown, by Figure 5It is evident that the prepared copper-based nickel-tungsten foam exhibits a three-dimensional porous multilayer structure. The surface of the copper foam is covered with a porous multilayer nickel-tungsten alloy. The three-dimensional porous multilayer structure is beneficial for increasing the specific surface area, increasing the number of active sites, promoting the contact between the electrolyte and the electrocatalyst, and the porous structure facilitates the rapid desorption of bubbles, reduces the accumulation of hydrogen bubbles on the electrode surface, and reduces polarization loss.
[0043] Example 3 This embodiment is the same as Embodiment 1, except that in this embodiment, when electroplating a porous, multi-layered nickel-tungsten alloy onto the foamed copper, the current is 10 A / cm. 2 .
[0044] The scanning electron microscope image of the porous multilayer nickel-tungsten alloy prepared in this embodiment is shown below. Figure 6 As shown, by Figure 6 It is evident that the prepared copper-based nickel-tungsten foam exhibits a three-dimensional porous multilayer structure. The surface of the copper foam is covered with a porous multilayer nickel-tungsten alloy. The three-dimensional porous multilayer structure is beneficial for increasing the specific surface area, increasing the number of active sites, promoting the contact between the electrolyte and the electrocatalyst, and the porous structure facilitates the rapid desorption of bubbles, reduces the accumulation of hydrogen bubbles on the electrode surface, and reduces polarization loss.
[0045] Comparative Example 1 This embodiment is the same as Embodiment 1, except that in this embodiment, when electroplating a porous, multi-layered nickel-tungsten alloy onto the foamed copper, the current is 1 A / cm. 2 The electroplating time is 30 minutes.
[0046] The scanning electron microscope images of the nickel-tungsten alloy prepared in this embodiment at different magnifications are shown below. Figure 7 As shown, by Figure 7 As can be seen from the 400x magnification, the nickel-tungsten alloy deposited on the surface of the foamed copper does not have a porous and multi-layered structure. On the contrary, the resulting coating is relatively flat, which reduces the specific surface area, permeability and mass transfer efficiency in the catalytic reaction.
[0047] Comparative Example 2 This embodiment is the same as Embodiment 1, except that in this embodiment, when electroplating a porous, multi-layered nickel-tungsten alloy onto the foamed copper, the current is 12 A / cm. 2 The electroplating time is 3 minutes.
[0048] The scanning electron microscope images of the nickel-tungsten alloy prepared in this embodiment at different magnifications are shown below. Figure 8 As shown, by Figure 8It is evident that the channels of the nickel-tungsten alloy are mainly mesopores, with pore sizes generally ranging from 10 to 50 micrometers. The distribution is highly uniform, and there are no large pores or through-holes caused by sintering or phase separation. Furthermore, the cross-section and surface morphology exhibit single-layer distribution characteristics, without layered composite or interface peeling phenomena.
[0049] Comparative Example 3 This embodiment is the same as Embodiment 1, except that the electroplating solution temperature is 45°C during electroplating. Scanning electron microscope images of the nickel-tungsten alloy prepared in this embodiment at different magnifications are shown below. Figure 9 As shown, by Figure 9 It is evident that the nickel-tungsten alloy has very few pores and does not exhibit multilayered structures.
[0050] Comparative Example 4 This embodiment is the same as Embodiment 1, except that the electroplating solution temperature is 100°C during electroplating. Scanning electron microscope images of the nickel-tungsten alloy prepared in this embodiment at different magnifications are shown below. Figure 10 As shown, by Figure 10 It is evident that the nickel-tungsten alloy has very few pores and does not exhibit multilayered structures.
[0051] Finally, it should be noted that the above embodiments of the present invention are merely examples for illustrating the present invention and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations and modifications based on the above description. It is impossible to exhaustively list all possible implementations here. All obvious variations or modifications derived from the technical solutions of the present invention are still within the protection scope of the present invention.
Claims
1. A method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance, characterized in that, Using copper foam as the negative electrode and a carbon plate or steel plate as the positive electrode, electroplating is performed in an electroplating bath at 60-80℃ for 1-10 minutes, thereby obtaining a porous, multilayer nickel-tungsten alloy on the copper foam. The current density during electroplating is 3-10 A / cm². 2 .
2. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 1, characterized in that, The method for preparing the foamed copper is as follows: The foam is placed in the vacuum chamber of a vacuum coating cleaving machine, then evacuated and filled with argon gas. Copper sheets with a purity of ≥99.9% are bombarded at 220-460V to deposit copper on the foam. The foam is then burned off to obtain foamed copper.
3. A method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 1 or 2, characterized in that, The electroplating solution is composed of the following components by mass percentage: nickel sulfate hexahydrate 1-15%, boric acid 1-15%, phosphate 1-15%, tungstate 1-15%, citric acid 1-15%, alkali 1-10%, and the remainder is deionized water.
4. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 3, characterized in that, The phosphate is one or more of sodium dihydrogen phosphate, sodium phosphate, ammonium dihydrogen phosphate, and ammonium phosphate.
5. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 3, characterized in that, The tungstate is one or more of sodium tungstate, potassium tungstate, and ammonium tungstate.
6. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 3, characterized in that, The alkali is one or more of sodium hydroxide, ammonia, and potassium hydroxide.
7. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 3, characterized in that, The pH of the electroplating solution is 6-10.
8. The method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 1, characterized in that, The current density is 3-5 A / cm² 2 .
9. A method for preparing a porous multilayer nickel-tungsten alloy with high hydrogen evolution performance according to claim 1 or 8, characterized in that, The temperature of the electroplating solution is 65-75℃.
10. A porous multilayer nickel-tungsten alloy with high hydrogen evolution performance, characterized in that, The porous multilayer nickel-tungsten alloy with high hydrogen evolution performance was prepared using any one of the preparation methods described in claims 1-9.