Electrolytic hydrogen production solid repelling cathode and modification method and application thereof

Abstract

The invention provides an electrolytic hydrogen production solid repelling cathode and a modification method and application thereof, and the modification method comprises the following steps: pretreating an HER electrode, and removing organic matters and an oxide layer on the surface of the HER electrode to obtain the pretreated HER electrode; and the pretreated HER electrode is soaked in an electroplating solution or a chemical plating solution containing silver ions for electroplating or chemical plating, silver particles are deposited on the surface of the HER electrode, and the modified electrolysis hydrogen production solid repelling cathode is obtained.

Description

Technical Field

[0001] This invention relates to the field of seawater electrolysis for hydrogen production technology, specifically to a solid cathode for hydrogen production by electrolysis, its modification method, and its application. Background Technology

[0002] With the continuous development of industrialization, new energy sources such as hydrogen are being increasingly applied across various industries. To meet the demand for hydrogen energy, large-scale hydrogen production is typically achieved through seawater electrolysis. Seawater is an inexhaustible electrolyte, but its neutral pH makes the cathode electrode prone to scaling, making it difficult to maintain long-term stability during seawater electrolysis. Developing a method to ensure the stability of common HER (Hydrogen Evolution Reaction) electrodes during electrolysis in neutral seawater presents a significant challenge.

[0003] Commonly used HER electrodes include nickel mesh, Raney nickel, nickel-molybdenum alloy, platinum-titanium felt, and stainless steel. Although they have good HER performance in seawater electrolysis, they will become deactivated due to the deposition of calcium and magnesium ions in seawater when used in a neutral seawater environment for a long time, which will greatly reduce the hydrogen production efficiency of the HER electrode. Summary of the Invention

[0004] The purpose of this invention is to provide an electrolytic hydrogen production cathode, its modification method and application, to overcome the problem that the HER electrode has poor stability during seawater electrolysis, which leads to a significant reduction in hydrogen production efficiency. This invention achieves long-term stability of the HER electrode during seawater electrolysis by electroplating Ag on the HER electrode.

[0005] This invention is achieved through the following technical solution: A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The HER electrode is pretreated to remove organic matter and oxide layer from its surface, resulting in a pretreated HER electrode. The pretreated HER electrode is immersed in an electroplating solution or chemical plating solution containing silver ions for electroplating or chemical plating, so that silver particles are deposited on the surface of the HER electrode to obtain a modified electrolytic hydrogen generation repulsion cathode.

[0006] Furthermore, the pretreatment of the HER electrode specifically involves immersing the HER electrode in an organic solvent and an acidic reagent sequentially for 5-10 minutes.

[0007] Furthermore, the organic solvent is at least one of acetone solution, ethanol solution and methanol solution, and the concentration of the organic solvent is 0.5 mol / L to 5 mol / L.

[0008] Furthermore, the acidic reagent is a sulfuric acid solution or a hydrochloric acid solution, and the concentration of the acidic reagent is 0.5 mol / L to 5 mol / L.

[0009] Furthermore, the electroplating solution or the chemical plating solution is a mixed solution comprising at least a silver salt solution and a sodium salt solution; The silver salt solution is a silver sulfate solution, a silver acetate solution, or a silver nitrate solution; The sodium salt solution is a sodium phosphate solution, a sodium citrate solution, or a sodium acetate solution.

[0010] Furthermore, in the electroplating solution, the concentration of silver salt is 0.001~0.01 mol / L, and the concentration of sodium salt is 0.01~0.1 mol / L; The electroless plating solution also includes a complexing agent and a reducing agent, wherein the concentration of silver salt is 0.001~0.01 mol / L, the concentration of sodium salt is 0.01~0.1 mol / L, the concentration of complexing agent is 0.01~1 mol / L, and the concentration of reducing agent is 0.01~1 mol / L.

[0011] Furthermore, the complexing agent is at least one selected from sodium tartrate, sodium citrate, ethylenediaminetetraacetic acid, and sodium pyrophosphate; The reducing agent is at least one of sodium hypophosphite, sodium borohydride, and borane.

[0012] Furthermore, the electroplating process conditions include: a temperature of 20~50℃, a voltage of -0.4~-0.6V, and a time of 3~10min; The electroless plating time is 10-20 minutes.

[0013] An electrolytic hydrogen production repulsion solid cathode is obtained using the above-mentioned modification method.

[0014] Application of a solid cathode for hydrogen production by electrolysis in seawater electrolysis.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: This invention uses the HER electrode as a substrate, electroplating a layer of silver onto its surface to increase the stability of the HER electrode in seawater. The silver on the surface reacts with magnesium hydroxide generated in the seawater to form a semi-coherent crystal plane. The lattice constant of silver can reach 4.0857 Å, while the lattice constant of magnesium hydroxide is only 3.19 Å. The lattice mismatch can be calculated using the formula ε=( _2 _1) / _2, where ε is the lattice mismatch degree (used to describe the geometric inconsistency caused by the difference in the equilibrium lattice constants of two different crystal materials when forming heterojunctions, epitaxial layers or superlattice structures). _2 is the lattice constant of silver. _1 represents the lattice constant of magnesium hydroxide. The lattice mismatch between silver and magnesium hydroxide can reach 0.22, belonging to a semi-coherent crystal plane. The lattice structures of the two materials at the interface are completely mismatched, preventing magnesium hydroxide atoms from forming continuous, defect-free connections on the electrode surface, thus achieving excellent scale prevention. Furthermore, HER activity testing revealed that plating a layer of silver does not affect the HER activity of the electrode; that is, the silver plating does not cover the active sites of the substrate itself, thus increasing the scale prevention behavior of the substrate without affecting its HER activity. Existing technologies, in order to increase the stability of the electrode in seawater, often modify the substrate structure into an array of pointed structures, using the tip effect to prevent magnesium hydroxide from adhering to the electrode. However, this method significantly reduces the contact area between the substrate and seawater, thereby greatly reducing the HER activity of the electrode itself.

[0016] Furthermore, the present invention employs silver electroplating, ensuring that the plated silver will not fall off during the electrolysis of seawater. This electroplating method also provides excellent adhesion between the silver and the substrate. In contrast, existing technologies, including sputtering and spraying, cannot effectively stabilize silver on the electrode surface.

[0017] This invention significantly improves the stability of the HER electrode in seawater electrolysis, while greatly extending its lifespan and utilization rate without affecting its HER activity. Compared to current methods for increasing stability, silver electroplating offers advantages such as protecting the electrode's HER activity and providing superior stability, making it particularly promising for applications in hydrogen electrolysis. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly described below. 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 from these drawings without creative effort.

[0019] Figure 1 Comparison of HER performance of platinum titanium felt, Raney nickel, nickel-molybdenum alloy, nickel mesh, and 304 stainless steel before silver plating; Figure 2 The graph shows a comparison of the HER performance of platinum titanium felt, Raney nickel, nickel-molybdenum alloy, nickel mesh, and silver-plated 304 stainless steel in Examples 1-5. Figure 3 Comparison of the stability of platinum titanium felt, Raney nickel, nickel-molybdenum alloy, nickel mesh, and 304 stainless steel in seawater before silver plating; Figure 4 Comparison of the stability of platinum titanium felt, Raney nickel, nickel-molybdenum alloy, nickel mesh, and silver-plated 304 stainless steel in seawater in Examples 1-5; Figure 5 A comparison diagram of the stability of nickel mesh in seawater after silver plating under the conditions of Example 6; Figure 6 A comparison diagram showing the stability of Raney nickel in seawater after silver plating under the conditions of Example 7; Figure 7 A comparison diagram of the stability of platinum-titanium felt in seawater after silver plating under the conditions of Example 8; Figure 8 A comparison diagram showing the stability of nickel-molybdenum alloy in seawater after silver plating under the conditions of Example 9; Figure 9 A comparison of the stability of 304 stainless steel in seawater after silver plating under the conditions of Example 10; Figure 10 A comparison diagram of the stability of nickel mesh in seawater after silver plating under the conditions of Example 11; Figure 11 A comparison diagram of the stability of Raney nickel in seawater after silver plating under the conditions of Example 12; Figure 12 A comparison diagram of the stability of platinum-titanium felt in seawater after silver plating under the conditions of Example 13; Figure 13 A comparison diagram showing the stability of nickel-molybdenum alloy in seawater after silver plating under the conditions of Example 14; Figure 14 A comparison of the stability of 304 stainless steel in seawater after silver plating under the conditions of Example 15; Figure 15 A comparison diagram of the stability of nickel mesh in seawater after silver plating under the conditions of Example 16; Figure 16 A comparison diagram of the stability of Raney nickel in seawater after silver plating under the conditions of Example 17; Figure 17 A comparison diagram of the stability of platinum-titanium felt in seawater after silver plating under the conditions of Example 18; Figure 18 A comparison diagram showing the stability of nickel-molybdenum alloy in seawater after silver plating under the conditions of Example 19; Figure 19 A comparison of the stability of 304 stainless steel in seawater after silver plating under the conditions of Example 20; Figure 20 A comparison diagram of the stability of nickel mesh in seawater after silver plating under the conditions of Example 21; Figure 21 A comparison diagram of the stability of Raney nickel in seawater after silver plating under the conditions of Example 22; Figure 22 A comparison diagram of the stability of platinum-titanium felt in seawater after silver plating under the conditions of Example 23; Figure 23 A comparison diagram showing the stability of nickel-molybdenum alloy in seawater after silver plating under the conditions of Example 24; Figure 24 A comparison of the stability of 304 stainless steel in seawater after silver plating under the conditions of Example 25; Figure 25 The images are SEM images of nickel mesh after silver plating under the conditions of Example 1, where (a) is a surface morphology image at a magnification of 1.3k, (b) is a surface morphology image at a magnification of 1.2k, (c) is a surface morphology image at a magnification of 60.0k, and (d) is a surface morphology image at a magnification of 35.0k. Figure 26 The following are energy dispersive spectroscopy (EDS) images of nickel mesh after silver plating under the conditions of Example 1, where (a) is the elemental distribution of Ag at a magnification of 60.0 k, (b) is the elemental distribution of Ni at a magnification of 60.0 k, and (c) is the surface morphology at a magnification of 60.0 k. Figure 27 The images are SEM images of Raney nickel after silver plating under the conditions of Example 2, where (a) is a surface morphology image at a magnification of 8.00k, (b) is a surface morphology image at a magnification of 8.00k, (c) is a surface morphology image at a magnification of 60.0k, and (d) is a surface morphology image at a magnification of 60.0k. Figure 28 The following are energy dispersive spectroscopy (EDS) spectra of Raney nickel after silver plating under the conditions of Example 2, where (a) is the elemental distribution of Ag at a magnification of 4.50 k, (b) is the elemental distribution of Ni at a magnification of 4.50 k, and (c) is the surface morphology at a magnification of 4.50 k. Figure 29 The images are SEM images of platinum-titanium felt after silver plating under the conditions of Example 3, where (a) is a surface morphology image at a magnification of 8.00k, (b) is a surface morphology image at a magnification of 60.0k, (c) is a surface morphology image at a magnification of 60.0k, and (d) is a surface morphology image at a magnification of 45.0k. Figure 30 The following are energy dispersive spectroscopy (EDS) images of platinum-titanium felt after silver plating under the conditions of Example 3, where (a) is the elemental distribution of Ag at a magnification of 8.00 k, (b) is the elemental distribution of Pt at a magnification of 8.00 k, (c) is the elemental distribution of Ti at a magnification of 8.00 k, and (d) is the surface morphology image at a magnification of 8.00 k. Figure 31 The images are SEM images of the nickel-molybdenum alloy after silver plating under the conditions of Example 4, where (a) is a surface morphology image at a magnification of 8.00k, (b) is a surface morphology image at a magnification of 4.50k, (c) is a surface morphology image at a magnification of 60.0k, and (d) is a surface morphology image at a magnification of 60.0k. Figure 32 The following are energy dispersive spectroscopy (EDS) images of nickel-molybdenum alloy after silver plating under the conditions of Example 4, where (a) is the elemental distribution of Ag at a magnification of 4.50 k, (b) is the elemental distribution of Ni at a magnification of 4.50 k, (c) is the elemental distribution of Mo at a magnification of 4.50 k, and (d) is the surface morphology image at a magnification of 4.50 k. Figure 33 SEM images of 304 stainless steel after silver plating under the conditions of Example 5 are shown, where (a) is a surface morphology image at a magnification of 60.0k, (b) is a surface morphology image at a magnification of 60.0k, (c) is a surface morphology image at a magnification of 35.0k, and (d) is a surface morphology image at a magnification of 60.0k. Figure 34 The following are energy dispersive spectroscopy (EDS) spectra of 304 stainless steel after silver plating under the conditions of Example 5, where (a) is the elemental distribution of Ag at a magnification of 4.50 k, (b) is the elemental distribution of Fe at a magnification of 4.50 k, (c) is the elemental distribution of Cr at a magnification of 4.50 k, and (d) is the surface morphology at a magnification of 4.50 k. Detailed Implementation

[0020] The present invention will now be described in detail: To address the poor stability of HER electrodes during seawater electrolysis, this invention electroplats or chemically plates Ag onto common HER electrodes, enabling them to maintain stability for extended periods during seawater electrolysis. Impurities on the HER electrode surface are removed through pretreatment, and then a silver layer is coated onto the surface using an in-situ electrochemical synthesis method. By applying lattice mismatch theory—because the lattice mismatch between Ag and magnesium hydroxide reaches 0.22, the lattice structures of the two materials are completely mismatched at the interface—silver cannot adhere to the electrode surface, thus improving the anti-scaling performance of the HER electrode.

[0021] Specifically, it includes the following steps: Step 1: Pre-treat the HER electrode by soaking it in organic solvents and acidic reagents for 5-10 minutes in sequence to remove organic matter and oxide layer from the surface of the HER electrode.

[0022] The organic solvent includes at least one of acetone solution, ethanol solution, and methanol solution.

[0023] Furthermore, the concentration of the organic solvent is 0.5 mol / L to 5 mol / L.

[0024] Furthermore, the acidic reagent includes either sulfuric acid or hydrochloric acid, with a concentration of 0.5 mol / L to 5 mol / L.

[0025] Step 2: Immerse the pretreated HER electrode in an electroplating solution or chemical plating solution containing silver ions for electroplating or chemical plating. The silver ions form metal particles that are deposited on the surface of the HER electrode (substrate).

[0026] The HER electrode includes any one of nickel mesh, Raney nickel, platinum titanium felt, nickel-molybdenum alloy, and stainless steel.

[0027] The electroplating solution or the electroless plating solution is a mixed solution comprising at least a silver salt solution and a sodium salt solution; the sodium salt solution can increase the complexation ability between silver and the substrate.

[0028] The silver salt solution includes any one of silver sulfate solution, silver acetate solution, and silver nitrate solution.

[0029] The sodium salt solution includes any one of sodium pyrophosphate solution, sodium citrate solution, and sodium acetate solution.

[0030] The electroplating process conditions include: a temperature of 20~50℃, a voltage of -0.4~-0.6V, a time of 3~10min, and in the electroplating solution, the concentration of silver salt is 0.001~0.01mol / L and the concentration of sodium salt is 0.01~0.1mol / L.

[0031] The electroless plating process conditions include: the electroless plating solution containing 0.001~0.01 mol / L silver salt, 0.01~0.1 mol / L sodium salt, 0.01~1 mol / L complexing agent, and 0.01~1 mol / L reducing agent; and the electroless plating time being 10~20 min. The complexing agent includes at least one selected from sodium tartrate, sodium citrate, ethylenediaminetetraacetic acid, and sodium pyrophosphate. The reducing agent includes at least one selected from sodium hypophosphite, sodium borohydride, and borane.

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise specified, the methods and experimental equipment used in the following embodiments are conventional methods and instruments.

[0033] Example 1 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The nickel mesh is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 5 minutes to remove organic matter and oxide layer from the surface of the nickel mesh, thereby obtaining a pretreated nickel mesh. The organic solvent is an acetone solution with a concentration of 0.5 mol / L; the acidic reagent is a sulfuric acid solution with a concentration of 0.5 mol / L.

[0034] The pretreated nickel mesh is immersed in an electroplating solution containing silver ions for electroplating. The electroplating solution is a mixture of silver salt solution and sodium salt solution. The silver salt solution is silver sulfate solution, and the sodium salt solution is sodium phosphate solution. The concentration of silver salt in the electroplating solution is 0.001 mol / L, and the concentration of sodium salt is 0.01 mol / L. The electroplating process conditions include a temperature of 20℃, a voltage of -0.4V, and a time of 3min, so that silver particles are deposited on the surface of the nickel mesh to obtain a modified electrolytic hydrogen generation repulsion cathode.

[0035] Example 2 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: Raney nickel is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 6 minutes to remove organic matter and oxide layer from the surface of the Raney nickel, thereby obtaining pretreated Raney nickel. The organic solvent is an ethanol solution with a concentration of 3 mol / L; the acidic reagent is a hydrochloric acid solution with a concentration of 3 mol / L.

[0036] Pretreated Raney nickel was immersed in an electroplating solution containing silver ions for electroplating. The electroplating solution was a mixture of silver salt solution and sodium salt solution. The silver salt solution was silver acetate solution, and the sodium salt solution was sodium citrate solution. The concentration of silver salt in the electroplating solution was 0.005 mol / L, and the concentration of sodium salt was 0.05 mol / L. The electroplating process conditions included a temperature of 30°C, a voltage of -0.5V, and a time of 5 min, so that silver particles were deposited on the surface of Raney nickel to obtain a modified electrolytic hydrogen production repulsion cathode.

[0037] Example 3 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The platinum-titanium felt is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 8 minutes to remove organic matter and oxide layer from the surface of the platinum-titanium felt, thereby obtaining the pretreated platinum-titanium felt. The organic solvent is a methanol solution with a concentration of 5 mol / L; the acidic reagent is a sulfuric acid solution with a concentration of 5 mol / L.

[0038] The pretreated platinum-titanium felt was immersed in an electroplating solution containing silver ions for electroplating. The electroplating solution was a mixture of silver salt solution and sodium salt solution. The silver salt solution was silver nitrate solution, and the sodium salt solution was sodium acetate solution. The concentration of silver salt in the electroplating solution was 0.01 mol / L, and the concentration of sodium salt was 0.1 mol / L. The electroplating process conditions included a temperature of 50℃, a voltage of -0.6V, and a time of 10min, so that silver particles were deposited on the surface of the platinum-titanium felt to obtain a modified electrolytic hydrogen generation repulsion cathode.

[0039] Example 4 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The nickel-molybdenum alloy is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 8 minutes to remove organic matter and oxide layer from the surface of the nickel-molybdenum alloy, thereby obtaining the pretreated nickel-molybdenum alloy. The organic solvent is an acetone solution with a concentration of 4 mol / L; the acidic reagent is a sulfuric acid solution with a concentration of 4 mol / L.

[0040] The pretreated nickel-molybdenum alloy was immersed in a chemical plating solution containing silver ions for chemical plating. The chemical plating solution was a mixed solution of silver salt solution, sodium salt solution, complexing agent, and reducing agent. The complexing agent was a mixture of sodium tartrate and sodium citrate in a 1:1 mass ratio, and the reducing agent was a mixture of sodium hypophosphite and sodium borohydride in a 1:1 mass ratio. The silver salt solution was a silver sulfate solution, and the sodium salt solution was a sodium citrate solution. In the chemical plating solution, the concentration of silver salt was 0.01 mol / L, the concentration of sodium salt was 0.01 mol / L, the concentration of complexing agent was 1 mol / L, and the concentration of reducing agent was 1 mol / L. The chemical plating time was 10 min, so that silver particles were deposited on the surface of the nickel-molybdenum alloy to obtain a modified electrolytic hydrogen generation repulsion cathode.

[0041] Example 5 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The 304 stainless steel is pretreated by immersing it in an organic solvent and an acidic reagent for 10 min in sequence to remove organic matter and oxide layer from the surface of the 304 stainless steel, thereby obtaining pretreated 304 stainless steel. The organic solvent is a mixture of ethanol solution and methanol solution in a volume ratio of 1:1, and the concentration of the organic solvent is 3 mol / L. The acidic reagent is sulfuric acid solution, and the concentration of the acidic reagent is 4 mol / L.

[0042] Pretreated 304 stainless steel was immersed in a chemical plating solution containing silver ions for chemical plating. The chemical plating solution was a mixed solution of silver salt solution, sodium salt solution, complexing agent, and reducing agent. The complexing agent was ethylenediaminetetraacetic acid (EDTA), the reducing agent was borane, the silver salt solution was silver acetate solution, and the sodium salt solution was sodium acetate solution. In the chemical plating solution, the concentration of silver salt was 0.001 mol / L, the concentration of sodium salt was 0.1 mol / L, the concentration of complexing agent was 0.01 mol / L, and the concentration of reducing agent was 0.01 mol / L. The chemical plating time was 20 min, so that silver particles were deposited on the surface of 304 stainless steel, resulting in a modified electrolytic hydrogen generation cathode.

[0043] Example 6 The difference from Example 1 is that the temperature in the electroplating process is 50°C.

[0044] Example 7 The difference from Example 2 is that the temperature in the electroplating process is 50°C.

[0045] Example 8 The difference from Example 3 is that the voltage in the electroplating process is -0.5V.

[0046] Example 9 The difference from Example 4 is that the electroless plating time is 20 min.

[0047] Example 10 The difference from Example 5 is that the concentration of silver salt in the electroless plating solution is 0.01 mol / L.

[0048] Example 11 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The nickel mesh is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 10 minutes to remove organic matter and oxide layer from the surface of the nickel mesh, thereby obtaining a pretreated nickel mesh. The organic solvent is a mixture of ethanol solution and methanol solution in a volume ratio of 1:1, and the concentration of the organic solvent is 3 mol / L. The acidic reagent is a sulfuric acid solution with a concentration of 4 mol / L.

[0049] The pretreated nickel mesh is immersed in a chemical plating solution containing silver ions for chemical plating. The chemical plating solution is a mixed solution of silver salt solution, sodium salt solution, complexing agent and reducing agent. The complexing agent is ethylenediaminetetraacetic acid, the reducing agent is borane, the silver salt solution is silver acetate solution, and the sodium salt solution is sodium acetate solution. In the chemical plating solution, the concentration of silver salt is 0.01 mol / L, the concentration of sodium salt is 0.01 mol / L, the concentration of complexing agent is 0.01 mol / L, and the concentration of reducing agent is 0.01 mol / L. The chemical plating time is 10 min, so that silver particles are deposited on the surface of the nickel mesh, resulting in a modified electrolytic hydrogen generation repulsion cathode.

[0050] Example 12 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: Raney nickel is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 10 min to remove organic matter and oxide layer from its surface, thus obtaining pretreated Raney nickel. The organic solvent is a mixture of ethanol and methanol in a 1:1 volume ratio with a concentration of 3 mol / L; the acidic reagent is a sulfuric acid solution with a concentration of 4 mol / L.

[0051] Pretreated Raney nickel was immersed in a chemical plating solution containing silver ions for chemical plating. The chemical plating solution was a mixed solution of silver salt solution, sodium salt solution, complexing agent, and reducing agent. The complexing agent was ethylenediaminetetraacetic acid (EDTA), the reducing agent was borane, the silver salt solution was silver acetate solution, and the sodium salt solution was sodium acetate solution. In the chemical plating solution, the concentration of silver salt was 0.01 mol / L, the concentration of sodium salt was 0.1 mol / L, the concentration of complexing agent was 1 mol / L, and the concentration of reducing agent was 1 mol / L. The chemical plating time was 10 min, so that silver particles were deposited on the surface of Raney nickel, resulting in a modified electrolytic hydrogen generation cathode.

[0052] Example 13 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The platinum-titanium felt is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 10 min to remove organic matter and oxide layer from the surface of the platinum-titanium felt, thereby obtaining pretreated platinum-titanium felt. The organic solvent is a mixture of ethanol solution and methanol solution in a volume ratio of 1:1, and the concentration of the organic solvent is 3 mol / L. The acidic reagent is sulfuric acid solution, and the concentration of the acidic reagent is 4 mol / L.

[0053] The pretreated platinum-titanium felt was immersed in a chemical plating solution containing silver ions for chemical plating. The chemical plating solution was a mixed solution of silver salt solution, sodium salt solution, complexing agent, and reducing agent. The complexing agent was ethylenediaminetetraacetic acid (EDTA), the reducing agent was borane, the silver salt solution was silver acetate solution, and the sodium salt solution was sodium acetate solution. In the chemical plating solution, the concentration of silver salt was 0.001 mol / L, the concentration of sodium salt was 0.01 mol / L, the concentration of complexing agent was 1 mol / L, and the concentration of reducing agent was 1 mol / L. The chemical plating time was 20 min, so that silver particles were deposited on the surface of the platinum-titanium felt, resulting in a modified electrolytic hydrogen generation repulsion cathode.

[0054] Example 14 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The nickel-molybdenum alloy is pretreated by sequentially immersing it in an organic solvent and an acidic reagent for 6 minutes to remove organic matter and oxide layer from the surface of the nickel-molybdenum alloy, thereby obtaining the pretreated nickel-molybdenum alloy. The organic solvent is an ethanol solution with a concentration of 3 mol / L; the acidic reagent is a hydrochloric acid solution with a concentration of 3 mol / L.

[0055] The pretreated nickel-molybdenum alloy was immersed in an electroplating solution containing silver ions for electroplating. The electroplating solution was a mixture of silver salt solution and sodium salt solution. The silver salt solution was silver acetate solution, and the sodium salt solution was sodium citrate solution. The concentration of silver salt in the electroplating solution was 0.005 mol / L, and the concentration of sodium salt was 0.05 mol / L. The electroplating process conditions included a temperature of 30℃, a voltage of -0.5V, and a time of 10min, so that silver particles were deposited on the surface of the nickel-molybdenum alloy to obtain a modified electrolytic hydrogen production repulsion cathode.

[0056] Example 15 A method for modifying a solid cathode for electrolytic hydrogen production includes the following steps: The 304 stainless steel is pretreated by immersing it in an organic solvent and an acidic reagent for 6 minutes in sequence to remove organic matter and oxide layer from the surface of the 304 stainless steel, thereby obtaining pretreated 304 stainless steel. The organic solvent is an ethanol solution with a concentration of 3 mol / L; the acidic reagent is a hydrochloric acid solution with a concentration of 3 mol / L.

[0057] Pretreated 304 stainless steel is immersed in an electroplating solution containing silver ions for electroplating. The electroplating solution is a mixture of silver salt solution and sodium salt solution. The silver salt solution is silver acetate solution, and the sodium salt solution is sodium citrate solution. The concentration of silver salt in the electroplating solution is 0.01 mol / L, and the concentration of sodium salt is 0.1 mol / L. The electroplating process conditions include a temperature of 30℃, a voltage of -0.5V, and a time of 10min, so that silver particles are deposited on the surface of 304 stainless steel to obtain a modified electrolytic hydrogen generation repulsion cathode.

[0058] Example 16 The difference from Example 11 is that the electroless plating time is 20 min.

[0059] Example 17 The difference from Example 12 is that the concentration of silver salt in the electroless plating solution is 0.001 mol / L, and the electroless plating time is 20 min.

[0060] Example 18 The difference from Example 13 is that in the electroless plating solution, the concentration of silver salt is 0.005 mol / L, the concentration of sodium salt is 0.1 mol / L, the concentration of complexing agent is 0.1 mol / L, and the concentration of reducing agent is 0.1 mol / L.

[0061] Example 19 The difference from Example 14 is that the electroplating process conditions are 40°C and -0.45V.

[0062] Example 20 The difference from Example 15 is that the electroplating process conditions are 35°C, -0.42V, and 5min.

[0063] Example 21 The difference from Example 1 is that the concentration of silver salt in the electroplating solution is 0.01 mol / L, and the electroplating process conditions are -0.43V and 6min.

[0064] Example 22 The difference from Example 2 is that the concentration of silver salt in the electroplating solution is 0.004 mol / L, the concentration of sodium salt is 0.04 mol / L, and the temperature in the electroplating process is 25°C.

[0065] Example 23 The difference from Example 3 is that the concentration of silver salt in the electroplating solution is 0.002 mol / L, the concentration of sodium salt is 0.02 mol / L, and the electroplating process conditions are 45°C, -0.41V, and 5min.

[0066] Example 24 The difference from Example 4 is that the concentration of the complexing agent is 0.5 mol / L, the concentration of the reducing agent is 0.5 mol / L, and the electroless plating time is 15 min.

[0067] Example 25 The difference from Example 5 is that the concentration of the complexing agent is 0.08 mol / L, the concentration of the reducing agent is 0.08 mol / L, and the electroless plating time is 18 min.

[0068] from Figure 1 and Figure 2 The HER activity of platinum-titanium felt, Raney nickel, nickel-molybdenum alloy, nickel mesh, and 304 stainless steel before and after silver plating in Examples 1-5 are respectively represented. Figure 1 and Figure 2 It can be seen that the HER performance of the electrode does not change before and after silver plating. Figure 3 This indicates the stability of each electrode before silver plating in Examples 1-5. Figure 4 This demonstrates the stability of each electrode after silver plating in Examples 1-5. The stability was assessed by analyzing the voltage difference before and after plating each electrode. Figure 3 It is clearly visible that the voltage fluctuations were large and the stability was poor before silver plating; from Figure 4 It is clearly visible that the voltage fluctuation is smaller and the stability is better after silver plating.

[0069] from Figure 5 , Figure 10 , Figure 15 , Figure 20 Corresponding to Examples 6, 11, 16, and 21 respectively, although the different examples changed the method and condition parameters for loading silver onto the nickel mesh, Figure 5 , Figure 10 , Figure 15 , Figure 20 This indicates that silver loaded on nickel mesh exhibits good stability in seawater.

[0070] from Figure 6 , Figure 11 , Figure 16 , Figure 21 Corresponding to Examples 7, 12, 17, and 22 respectively, although the different examples changed the method and condition parameters for loading silver onto Raney nickel, Figure 6 , Figure 11 , Figure 16 , Figure 21 This indicates that Raney nickel loaded with silver exhibits good stability in seawater.

[0071] from Figure 7 , Figure 12 , Figure 17 , Figure 22 Corresponding to Examples 8, 13, 18, and 23 respectively, although the different examples changed the method and condition parameters for loading silver on the platinum-titanium felt, Figure 7 , Figure 12 , Figure 17 , Figure 22 This indicates that silver loaded on the platinum-titanium felt exhibits good stability in seawater.

[0072] from Figure 8 , Figure 13 , Figure 18 , Figure 23 Corresponding to Examples 9, 14, 19, and 24 respectively, although the different examples changed the method and condition parameters for loading silver onto the nickel-molybdenum alloy, Figure 8 , Figure 13 , Figure 18 , Figure 23 This indicates that the nickel-molybdenum alloy loaded with silver exhibits good stability in seawater.

[0073] from Figure 9 , Figure 14 , Figure 19 , Figure 24 Corresponding to Examples 10, 15, 20, and 25 respectively, although the different examples changed the method and condition parameters for loading silver onto 304 stainless steel, Figure 9 , Figure 14 , Figure 19 , Figure 24 This indicates that 304 stainless steel loaded with silver exhibits good stability in seawater.

[0074] Figure 25 , 26 The above two images show the SEM and energy dispersive spectroscopy (EDS) spectra of silver loaded onto the nickel mesh. These two images fully demonstrate that Ag can be uniformly loaded onto the nickel mesh and has a high content.

[0075] Figure 27 , 28 The above two images show the SEM and energy dispersive spectroscopy (EDS) spectra of silver loaded onto Raney nickel. These two images fully demonstrate that Ag can be uniformly loaded onto Raney nickel with a high content.

[0076] Figure 29 , 30The above two images show the SEM and energy dispersive spectroscopy (EDS) spectra of silver loaded onto the platinum-titanium felt. These two images fully demonstrate that Ag can be uniformly loaded onto the platinum-titanium felt and has a high content.

[0077] Figure 31 , 32 The above two images show the SEM and energy dispersive spectroscopy (EDS) spectra of silver loaded onto the nickel-molybdenum alloy. These two images fully demonstrate that Ag can be uniformly loaded onto the nickel-molybdenum alloy and has a high content.

[0078] Figure 33 , 34 The above two images show the SEM and energy dispersive spectroscopy (EDS) spectra of silver loaded onto 304 stainless steel. These two images fully demonstrate that Ag can be uniformly loaded onto 304 stainless steel and has a high content.

[0079] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone skilled in the art can make various modifications and alterations without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be determined by the claims.

Claims

1. A method for modifying a solid cathode used in electrolytic hydrogen production, characterized in that, Includes the following steps: The HER electrode is pretreated to remove organic matter and oxide layer from its surface, resulting in a pretreated HER electrode. The pretreated HER electrode is immersed in an electroplating solution or chemical plating solution containing silver ions for electroplating or chemical plating, so that silver particles are deposited on the surface of the HER electrode to obtain a modified electrolytic hydrogen generation repulsion cathode.

2. The method for modifying a solid cathode for electrolytic hydrogen production according to claim 1, characterized in that, The pretreatment of the HER electrode specifically involves immersing the HER electrode in an organic solvent and an acidic reagent for 5-10 minutes in sequence.

3. The method for modifying a solid cathode for electrolytic hydrogen production according to claim 2, characterized in that, The organic solvent is at least one of acetone solution, ethanol solution and methanol solution, and the concentration of the organic solvent is 0.5 mol / L to 5 mol / L.

4. A method for modifying a solid cathode for electrolytic hydrogen production according to claim 2, characterized in that, The acidic reagent is a sulfuric acid solution or a hydrochloric acid solution, and the concentration of the acidic reagent is 0.5 mol / L to 5 mol / L.

5. The method for modifying a solid cathode for electrolytic hydrogen production according to claim 1, characterized in that, The electroplating solution or the electroless plating solution is a mixed solution comprising at least a silver salt solution and a sodium salt solution; The silver salt solution is a silver sulfate solution, a silver acetate solution, or a silver nitrate solution; The sodium salt solution is a sodium phosphate solution, a sodium citrate solution, or a sodium acetate solution.

6. A method for modifying a solid cathode for electrolytic hydrogen production according to claim 5, characterized in that, In the electroplating solution, the concentration of silver salt is 0.001~0.01 mol / L, and the concentration of sodium salt is 0.01~0.1 mol / L; The electroless plating solution also includes a complexing agent and a reducing agent, wherein the concentration of silver salt is 0.001~0.01 mol / L, the concentration of sodium salt is 0.01~0.1 mol / L, the concentration of complexing agent is 0.01~1 mol / L, and the concentration of reducing agent is 0.01~1 mol / L.

7. The method for modifying a solid cathode for electrolytic hydrogen production according to claim 6, characterized in that, The complexing agent is at least one of sodium tartrate, sodium citrate, ethylenediaminetetraacetic acid, and sodium pyrophosphate. The reducing agent is at least one of sodium hypophosphite, sodium borohydride, and borane.

8. The method for modifying a solid cathode for electrolytic hydrogen production according to claim 1, characterized in that, The electroplating process conditions include: temperature of 20~50℃, voltage of -0.4~-0.6V, and time of 3~10min; The electroless plating time is 10-20 minutes.

9. A solid-state cathode for electrolytic hydrogen production, characterized in that, It is obtained by the modification method described in any one of claims 1-8.

10. The application of the electrolytic hydrogen production solid cathode as described in claim 9 in seawater electrolytic hydrogen production.

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