Preparation method of three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and bubble one-way control

Abstract

The invention discloses a preparation method of a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and bubble one-way control, and belongs to the technical field of new energy electrolytic hydrogen production and fluid transportation. An electrode substrate and a gas control grid are printed based on a surface projection micro-stereo lithography printing technology, asymmetric wettability treatment is carried out on the gas control grid at the top of an electrode through nano silicon dioxide, and bubbles are controlled in a one-way mode through the super-aerophile characteristic of the nano silicon dioxide; and a cobalt-nickel-phosphorus alloy catalyst is deposited on the surface of the bottom three-dimensional electrode through chemical deposition, so that the functions of efficient hydrogen production through water electrolysis and hydrogen product separation are achieved, and the three-dimensional hydrogen production functional electrode and the preparation method thereof are easy to operate and excellent in hydrogen production performance. The prepared three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and bubble one-way control has the characteristics of large-area stacking and splicing, and the electrolytic efficiency can be improved while the space utilization rate can be increased.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy electrolytic hydrogen production and fluid transportation, and specifically relates to a method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles. Background Art

[0002] As a clean energy carrier, hydrogen has the characteristics of zero carbon emissions. When it is burned or generated through fuel cells, it only produces water vapor and does not release greenhouse gases or pollutants. As a clean and sustainable hydrogen production technology, hydrogen production by water electrolysis has far-reaching significance for promoting energy transformation and solving energy storage and transportation problems. Therefore, the design and development of functional electrodes with efficient water electrolysis hydrogen production and hydrogen transportation and collection will provide new research ideas for the development and transformation of hydrogen energy technology. Existing water electrolysis hydrogen production electrodes mainly rely on self-supporting nickel foam and carbon paper as substrates, and attach catalysts to the substrates. However, due to the porous and multi-micro-nano structure of the electrode, hydrogen bubbles in the process of water electrolysis hydrogen production cannot escape by themselves, which in turn affects the reaction and performance testing. Intervention of the behavior of hydrogen bubbles in water electrolysis hydrogen production by external physical means cannot achieve the removal of hydrogen bubbles on the electrode surface, which ultimately affects the catalytic active sites of the electrode and reduces the electrode catalytic efficiency. The water electrolysis hydrogen production electrode designed using wettability engineering shows excellent performance in bubble control behavior. The electrode consists of a catalytic area and an asymmetric wettability bubble control area, which is equivalent to the catalytic area, limiting the rational use of the electrode catalytic area, resulting in poor overall electrode performance. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles.

[0004] The present invention provides a method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation, aiming to solve the bubble control problem of the existing water electrolysis electrode in the hydrogen evolution reaction. The present invention makes full use of asymmetric wettability engineering and unidirectional bubble manipulation technology to perform ultra-fast directional manipulation, transportation and collection of hydrogen produced by water electrolysis to achieve "cleaning" of bubbles on the electrode surface and reconstruction of catalytic active sites. At the same time, the gas manipulation grid and the electrode substrate are assembled up and down without spatial interference, achieving perfect utilization of space, and showing excellent performance in water electrolysis hydrogen production performance and bubble manipulation behavior; the top gas manipulation grid of the three-dimensional electrolytic hydrogen production functional electrode is treated with asymmetric wettability to form a Laplace pressure difference in the gas-liquid-solid three-phase, and the bubbles generated on the electrode surface are transported from bottom to top. The bubble manipulation grid is treated with asymmetric wettability, that is, the bottom of the grid is hydrophilic (contact angle less than 30°), and the top is treated with nano-silicon dioxide spraying to form super-hydrophobic (contact angle greater than 150°). Therefore, these two different wettability interfaces constitute the asymmetric wettability of the bubble manipulation grid. This longitudinally distributed three-dimensional electrolytic hydrogen production functional electrode that does not occupy the catalytic area can simultaneously meet excellent catalytic performance and bubble manipulation performance. In addition, the three-dimensional electrolytic hydrogen production functional electrode can be assembled up and down by the bubble manipulation grid and the catalytic substrate to achieve reasonable application of space, such as large-area splicing of the three-dimensional electrolytic hydrogen production functional electrode in the plane, or stacking application of the three-dimensional electrolytic hydrogen production functional electrode in space.

[0005] A method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation, characterized in that the preparation method is specifically completed according to the following steps:

[0006] 1. Using 3D modeling software to establish a 3D model of a 3D electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control; the 3D electrolytic hydrogen production functional electrode is composed of an electrode substrate and a gas control grid;

[0007] The electrode substrate described in step 1 is an irregular three-dimensional surface;

[0008] The gas manipulation grid described in step 1 is composed of polygonal through holes and polygonal cross sections, and the polygonal through holes are connected by polygonal cross sections to form an integral grid structure;

[0009] 2. Use the corresponding slicing software to slice the 3D model, and transfer the sliced ​​model to the control system of the light-curing 3D printer;

[0010] 3. Use a photo-curing 3D printer to print layer by layer to obtain the electrode substrate and gas control grid required for the three-dimensional electrolysis hydrogen production functional electrode;

[0011] 4. Use a 405nm ultraviolet lamp to irradiate the printed electrode substrate and gas control grid for a period of time to obtain a cured electrode substrate and gas control grid;

[0012] 5. depositing the cobalt-nickel-phosphorus alloy catalyst on the solidified electrode substrate by chemical plating to obtain an electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited;

[0013] 6. Soaking the solidified gas control grid in hydrochloric acid for a period of time, using ultrasonic oscillation, taking it out and drying it to obtain a gas control grid treated with hydrochloric acid;

[0014] 7. Fix the gas manipulation grid treated with hydrochloric acid on a glass slide, and then use a hydrophobic material whose main component is nano-silicon dioxide particles to evenly spray the upper surface and side walls of the gas manipulation grid treated with hydrochloric acid, and then dry it to obtain a gas manipulation grid with an asymmetric wettability gradient;

[0015] 8. Assemble the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst and the gas manipulation grid with an asymmetric wettability gradient, so that the gas manipulation grid with an asymmetric wettability gradient is arranged on the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst, and obtain a three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation.

[0016] The gas manipulation grid with an asymmetric wettability gradient obtained in step seven of the present invention exhibits air-repellent properties at the bottom, and super-air-philic properties at the sidewalls and the top.

[0017] The three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared by the present invention can ensure extremely high catalytic efficiency while utilizing the Laplace pressure difference formed by the asymmetric wettability of the bubble control grid to actively detach the bubbles generated and gathered on the catalyst surface from bottom to top, thereby alleviating the obstruction of the catalytic area, accelerating the ion exchange rate, and promoting the catalytic reaction.

[0018] The working process of the three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional bubble control in the present invention is as follows:

[0019] The three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles prepared by the present invention is placed in a three-electrode electrolytic hydrogen production acidic electrolyzer, and the three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles prepared by the present invention is used as a working electrode, graphite is used as a counter electrode, and silver / silver chloride is used as a reference electrode; after power is turned on, hydrogen bubbles nucleate, aggregate, and grow on the surface of the cobalt-nickel-phosphorus alloy catalyst of the three-dimensional electrolytic hydrogen production functional electrode. When the volume of the hydrogen bubbles expands to the point where they touch the gas with asymmetric wettability gradient at the top, the hydrogen bubbles are heated to a temperature of 100 °C. After manipulating the grid, under the action of the combined force, the bubbles will be quickly adsorbed from the electrode surface to the top of the grid, thus undergoing an ultra-fast unidirectional detachment process from bottom to top, thereby completing the transport of hydrogen bubbles; during the hydrogen production and bubble manipulation process, the asymmetric wettability gradient is manifested at the top and bottom of the grid, that is, the top is super hydrophobic and the bottom is hydrophilic; in this asymmetric interfacial wettability, a dominant Laplace pressure difference will be generated in the gas-liquid-solid three-phase, which can transport bubbles unidirectionally from the catalyst interface to the top.

[0020] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0021] 1. The three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared by the present invention has higher hydrogen production efficiency and bubble control efficiency than the one-dimensional planar electrolytic hydrogen production functional electrode;

[0022] Second, the three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared by the present invention can control a single bubble to actively detach from the catalytic electrode surface from bottom to top within 20 milliseconds, and has good stability performance;

[0023] 3. The chemically deposited cobalt-nickel-phosphorus alloy catalyst exhibits a low overpotential, and the electrode catalytic performance does not decay in long-term hydrogen production experiments;

[0024] 4. The three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared by the present invention has the characteristics of large-area stacking and splicing, which can enhance space utilization and accelerate electrolysis efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is a schematic structural diagram of a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control in Example 1, in which 1 is a nano-silicon dioxide coating, 2 is a gas control grid, 3 is a cobalt-nickel-phosphorus alloy catalyst, and 4 is an electrode substrate;

[0026] Figure 2 This is a scanning electron microscope magnified image of the nano-silicon dioxide coating on the gas manipulation grid in step 7 of Example 1;

[0027] Figure 3This is a scanning electron microscope magnified image of the cobalt-nickel-phosphorus alloy catalyst on the electrode substrate in step 5 of Example 1;

[0028] Figure 4 A physical picture of a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1;

[0029] Figure 5 This is a diagram of the experimental process of hydrogen production by electrolysis and bubble control using a three-dimensional hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1;

[0030] Figure 6 Current density performance images of 1D, 2D, and 3D electrodes. DETAILED DESCRIPTION

[0031] Specific implementation method 1: This implementation method is a method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control, which is specifically completed in the following steps:

[0032] 1. Using 3D modeling software to establish a 3D model of a 3D electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control; the 3D electrolytic hydrogen production functional electrode is composed of an electrode substrate and a gas control grid;

[0033] The electrode substrate described in step 1 is an irregular three-dimensional surface;

[0034] The gas manipulation grid described in step 1 is composed of polygonal through holes and polygonal cross sections, and the polygonal through holes are connected by polygonal cross sections to form an integral grid structure;

[0035] 2. Use the corresponding slicing software to slice the 3D model, and transfer the sliced ​​model to the control system of the light-curing 3D printer;

[0036] 3. Use a photo-curing 3D printer to print layer by layer to obtain the electrode substrate and gas control grid required for the three-dimensional electrolysis hydrogen production functional electrode;

[0037] 4. Use a 405nm ultraviolet lamp to irradiate the printed electrode substrate and gas control grid for a period of time to obtain a cured electrode substrate and gas control grid;

[0038] 5. depositing the cobalt-nickel-phosphorus alloy catalyst on the solidified electrode substrate by chemical plating to obtain an electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited;

[0039] 6. Soaking the solidified gas control grid in hydrochloric acid for a period of time, using ultrasonic oscillation, taking it out and drying it to obtain a gas control grid treated with hydrochloric acid;

[0040] 7. Fix the gas manipulation grid treated with hydrochloric acid on a glass slide, and then use a hydrophobic material whose main component is nano-silicon dioxide particles to evenly spray the upper surface and side walls of the gas manipulation grid treated with hydrochloric acid, and then dry it to obtain a gas manipulation grid with an asymmetric wettability gradient;

[0041] 8. Assemble the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst and the gas manipulation grid with an asymmetric wettability gradient, so that the gas manipulation grid with an asymmetric wettability gradient is arranged on the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst, and obtain a three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation.

[0042] Specific implementation method 2: This implementation method is different from specific implementation method 1 in that the irregular three-dimensional surface described in step 1 is a parabola curvature surface or a double parabola curvature surface. The other steps are the same as those in specific implementation method 1.

[0043] Specific implementation method 3: This implementation method is different from specific implementation method 1 or 2 in that: the polygonal through hole described in step 1 is rectangular, circular, triangular or pentagonal; the aperture range of the polygonal through hole is 100 μm to 600 μm; the polygonal cross section described in step 1 is a circular cross section or a rectangular cross section. The other steps are the same as specific implementation method 1 or 2.

[0044] Specific embodiment 4: This embodiment differs from specific embodiments 1 to 3 in that: the material of the electrode substrate required for the three-dimensional electrolytic hydrogen production functional electrode described in step 3 is a polymer photocurable resin; the material of the gas control grid required for the three-dimensional electrolytic hydrogen production functional electrode described in step 3 is a polymer photocurable resin; the polymer photocurable resin is purchased from Chongqing Mofang Precision Technology Co., Ltd., and the model is HTL (high temperature resistant resin). The other steps are the same as specific embodiments 1 to 3.

[0045] Specific implementation method 5: This implementation method is different from specific implementation methods 1 to 4 in that the illumination time in step 4 is 3 minutes to 5 minutes. The other steps are the same as those in specific implementation methods 1 to 4.

[0046] Specific embodiment 6: This embodiment differs from specific embodiments 1 to 5 in that: in step 5, the cobalt-nickel-phosphorus alloy catalyst is deposited on the electrode substrate by chemical plating, which is specifically completed by the following steps:

[0047] ①, immerse the cured electrode substrate in anhydrous ethanol for ultrasonic treatment for 10 minutes, repeat the above operation twice to remove oxides and impurities on the surface of the electrode substrate, and obtain a cleaned electrode substrate; immerse the cleaned electrode substrate in a mixture of 39.6mL water, 400μL of 37% dilute hydrochloric acid and 0.426g SnCl2 at a temperature of 45°C for 10 minutes. The electrode is sensitized in this step to obtain a sensitized electrode substrate;

[0048] ② Rinse the sensitized electrode substrate 3 to 5 times with deionized water, then dry it, and then put it into a mixture of 40 mL of water, 100 μL of 37% dilute hydrochloric acid and 0.005 g of PdCl2 at 45 ° C for 20 minutes to complete the activation process and obtain an activated electrode substrate;

[0049] ③. Add 0.657g NiSO4·6H2O and 0.703g CoSO4·7H2O to 80mL deionized water, stir evenly with a magnetic stirrer, then add 2.94g C6H5Na3O7 and 3.45g C4H4Na2O6 and continue stirring, then add 6.6g (NH4)2SO4 and 2.12g NaH2PO2 to the solution, and finally add NaOH to adjust the pH value of the solution to 8.0-9.0. After stirring evenly, add deionized water to a beaker with a measuring cylinder, dilute to 100mL, and heat the solution to 70℃ for 10min to obtain a deposition solution;

[0050] ④. Immerse the activated electrode substrate in the deposition solution for 3 to 5 minutes, take it out and dry it to obtain an electrode substrate with a cobalt-nickel-phosphorus alloy catalyst deposited on it. The other steps are the same as those in the first to fifth embodiments.

[0051] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that the thickness of the cobalt-nickel-phosphorus alloy catalyst on the surface of the electrode substrate in step 5 is 50 nm to 200 nm. The other steps are the same as those of specific embodiments 1 to 6.

[0052] Specific implementation eight: The difference between this implementation and specific implementations one to seven is that the concentration of the hydrochloric acid in step six is ​​0.1 mol / L; the soaking time in step six is ​​10 min to 15 min.

[0053] The other steps are the same as those in Specific Embodiments 1 to 7.

[0054] Specific embodiment 9: This embodiment differs from specific embodiments 1 to 8 in that: the hydrophobic material whose main component is nano-silicon dioxide particles described in step 7 is NeverWet produced by Rust-Oleum; the thickness of nano-silicon dioxide on the surface of the gas control grid in step 7 is 500nm to 1000nm; the drying temperature described in step 7 is 60℃ to 70℃, and the drying time is 10h to 12h. The other steps are the same as those of specific embodiments 1 to 8.

[0055] Specific embodiment 10: This embodiment differs from specific embodiments 1 to 9 in that the distance between the surface of the electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited and the gas control grid with an asymmetric wettability gradient described in step 8 is 200 μm to 600 μm. The other steps are the same as those of specific embodiments 1 to 9.

[0056] In this embodiment, the fixing and assembly are performed by ultra-thin double-sided adhesive or resin curing.

[0057] The following examples are used to verify the beneficial effects of the present invention:

[0058] Example 1: Combination Figure 1 to Figure 5 This embodiment is described. This embodiment is a method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control, which is specifically completed in the following steps:

[0059] 1. Using 3D modeling software to establish a 3D model of a 3D electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control; the 3D electrolytic hydrogen production functional electrode is composed of an electrode substrate and a gas control grid;

[0060] The electrode substrate described in step 1 is a double parabola curvature surface;

[0061] The gas manipulation grid described in step 1 is composed of polygonal through holes and polygonal cross sections, and the polygonal through holes are connected by polygonal cross sections to form an integral grid structure; the polygonal through holes described in step 1 are rectangular; the aperture of the polygonal through holes is a rectangle with a side length of 400 μm; the polygonal cross section described in step 1 is a rectangular cross section;

[0062] 2. Use the corresponding slicing software to slice the 3D model, and transfer the sliced ​​model to the control system of the light-curing 3D printer;

[0063] The material of the electrode substrate required for the three-dimensional electrolytic hydrogen production functional electrode described in step 3 is a polymer light-curing resin; the polymer light-curing resin is purchased from Chongqing Mofang Precision Technology Co., Ltd., and the model is HTL (high temperature resistant resin);

[0064] The material of the gas control grid required for the three-dimensional electrolytic hydrogen production functional electrode described in step 3 is a polymer light-curing resin; the polymer light-curing resin is purchased from Chongqing Mofang Precision Technology Co., Ltd., and the model is HTL (high temperature resistant resin);

[0065] 3. Use a photo-curing 3D printer to print layer by layer to obtain the electrode substrate and gas control grid required for the three-dimensional electrolysis hydrogen production functional electrode;

[0066] 4. Use a 405nm ultraviolet lamp to irradiate the printed electrode substrate and gas control grid for a period of time to obtain a cured electrode substrate and gas control grid;

[0067] The illumination time described in step 4 is 5 minutes;

[0068] 5. depositing the cobalt-nickel-phosphorus alloy catalyst on the solidified electrode substrate by chemical plating to obtain an electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited;

[0069] 6. Soak the solidified gas control grid in hydrochloric acid for 1 hour, and use ultrasonic oscillation, take it out and dry it to obtain the gas control grid treated with hydrochloric acid;

[0070] The concentration of hydrochloric acid described in step 6 is 0.1 mol / L;

[0071] 7. Fix the gas manipulation grid treated with hydrochloric acid on a glass slide, and then use a hydrophobic material whose main component is nano-silicon dioxide particles to evenly spray the upper surface and side walls of the gas manipulation grid treated with hydrochloric acid, and then dry it to obtain a gas manipulation grid with an asymmetric wettability gradient;

[0072] The hydrophobic material described in step 7, whose main component is nano-silicon dioxide particles, is NeverWet produced by Rust-Oleum;

[0073] In step 7, the thickness of the nano-silicon dioxide on the surface of the gas control grid is 500nm to 800nm;

[0074] The drying temperature in step 7 is 60°C and the drying time is 12h;

[0075] 8. Assembling the electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited and the gas manipulation grid with an asymmetric wettability gradient, so that the gas manipulation grid with an asymmetric wettability gradient is arranged on the electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited, to obtain a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation;

[0076] The distance between the surface of the electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited in step eight and the gas manipulation grid with an asymmetric wettability gradient is 400 μm.

[0077] In step 5 of Example 1, the cobalt-nickel-phosphorus alloy catalyst is deposited on the electrode substrate by chemical plating, which is specifically completed by the following steps:

[0078] ①, immerse the cured electrode substrate in anhydrous ethanol for ultrasonic treatment for 10 minutes, repeat the above operation twice to remove oxides and impurities on the surface of the electrode substrate, and obtain a cleaned electrode substrate; immerse the cleaned electrode substrate in a mixture of 39.6mL water, 400μL of 37% dilute hydrochloric acid and 0.426g SnCl2 at a temperature of 45°C for 10 minutes. The electrode is sensitized in this step to obtain a sensitized electrode substrate;

[0079] ② Rinse the sensitized electrode substrate 5 times with deionized water, dry it, and then put it into a mixture of 40 mL of water, 100 μL of 37% dilute hydrochloric acid and 0.005 g of PdCl2 at 45 ° C for 20 minutes to complete the activation process and obtain the activated electrode substrate;

[0080] ③. Add 0.657g NiSO4·6H2O and 0.703g CoSO4·7H2O to 80mL deionized water, stir evenly with a magnetic stirrer, then add 2.94g C6H5Na3O7 and 3.45g C4H4Na2O6 and continue stirring, then add 6.6g (NH4)2SO4 and 2.12g NaH2PO2 to the solution, and finally add NaOH to adjust the pH value of the solution to 8.0-9.0. After stirring evenly, add deionized water to a beaker with a measuring cylinder, dilute to 100mL, and heat the solution to 70℃ for 10min to obtain a deposition solution;

[0081] ④. Immerse the activated electrode substrate in the deposition solution for 5 minutes, take it out and dry it to obtain an electrode substrate with a cobalt-nickel-phosphorus alloy catalyst deposited thereon.

[0082] Figure 4 A physical picture of a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1;

[0083] Figure 5 This is a diagram of the experimental process of hydrogen production by electrolysis and bubble control using a three-dimensional hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1.

[0084] from Figure 4-Figure 5 It can be seen that a three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles can produce hydrogen.

[0085] Hydrogen production by water electrolysis Ⅰ:

[0086] The three-dimensional electrolytic hydrogen production functional electrode (3D electrode) based on wettability gradient and unidirectional control of bubbles prepared in Example 1 was placed in a three-electrode electrolytic hydrogen production acidic electrolytic cell, and a 0.1 mol / L sulfuric acid solution was added to the electrolytic cell. The three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional control of bubbles prepared in the present invention was used as a working electrode, graphite was used as a counter electrode, and silver / silver chloride was used as a reference electrode. After a constant voltage of 2V was applied, hydrogen bubbles nucleated, aggregated, and grew on the surface of the cobalt-nickel-phosphorus alloy catalyst of the three-dimensional electrolytic hydrogen production functional electrode. When the volume of the hydrogen bubbles expanded, the hydrogen bubbles formed a hydrogen bubble. After expanding to contact the gas manipulation grid with an asymmetric wettability gradient at the top, the bubbles will be rapidly adsorbed from the electrode surface to the top of the grid under the action of the combined force, thus undergoing an ultra-fast unidirectional detachment process from bottom to top, thereby completing the transport of hydrogen bubbles; during the hydrogen production and bubble manipulation process, the asymmetric wettability gradient is manifested at the top and bottom of the grid, that is, the top is super hydrophobic and the bottom is hydrophilic; in this asymmetric interfacial wettability, a dominant Laplace pressure difference will be generated in the gas-liquid-solid three-phase system, which can transport bubbles unidirectionally from the catalyst interface to the top.

[0087] Hydrogen production by electrolysis of water II: A one-dimensional common flat plate electrode (1D electrode) is used to replace the three-dimensional hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1. The other steps and parameters are the same as those of hydrogen production by electrolysis of water I.

[0088] Hydrogen production by electrolysis of water III: A two-dimensional electrode (2D electrode) is used to replace the three-dimensional hydrogen production functional electrode based on wettability gradient and unidirectional bubble control prepared in Example 1. Other steps and parameters are the same as those of hydrogen production by electrolysis of water I.

[0089] Figure 6 Current density performance images of 1D, 2D and 3D electrodes;

[0090] from Figure 6 It can be seen that: under the same voltage and experimental conditions, the current density of the three-dimensional electrolysis hydrogen production functional electrode (3D electrode) based on wettability gradient and unidirectional bubble manipulation prepared in Example 1 is 2.5 times higher than the current density of the two-dimensional electrode (2D electrode), and 8 times higher than the current density of the one-dimensional ordinary flat plate electrode (1D electrode) with the same catalytic surface area.

Claims

1. A method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control, characterized in that The preparation method is specifically completed according to the following steps:

1. Using 3D modeling software to establish a 3D model of a 3D electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control; the 3D electrolytic hydrogen production functional electrode is composed of an electrode substrate and a gas control grid; The electrode substrate described in step 1 is an irregular three-dimensional surface; The gas manipulation grid described in step 1 is composed of polygonal through holes and polygonal cross sections, and the polygonal through holes are connected by polygonal cross sections to form an integral grid structure; 2. Use the corresponding slicing software to slice the 3D model, and transfer the sliced ​​model to the control system of the light-curing 3D printer; 3. Use a photo-curing 3D printer to print layer by layer to obtain the electrode substrate and gas control grid required for the three-dimensional electrolysis hydrogen production functional electrode; 4. Use a 405nm ultraviolet lamp to irradiate the printed electrode substrate and gas control grid for a period of time to obtain a cured electrode substrate and gas control grid; 5. depositing the cobalt-nickel-phosphorus alloy catalyst on the solidified electrode substrate by chemical plating to obtain an electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited; 6. Soaking the solidified gas control grid in hydrochloric acid for a period of time and using ultrasonic oscillation, taking it out and drying it to obtain a gas control grid treated with hydrochloric acid; 7. Fix the gas manipulation grid treated with hydrochloric acid on a glass slide, and then use a hydrophobic material whose main component is nano-silicon dioxide particles to evenly spray the upper surface and side walls of the gas manipulation grid treated with hydrochloric acid, and then dry it to obtain a gas manipulation grid with an asymmetric wettability gradient; 8. Assemble the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst and the gas manipulation grid with an asymmetric wettability gradient, so that the gas manipulation grid with an asymmetric wettability gradient is arranged on the electrode substrate deposited with the cobalt-nickel-phosphorus alloy catalyst, and obtain a three-dimensional electrolysis hydrogen production functional electrode based on wettability gradient and unidirectional bubble manipulation.

2. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The irregular three-dimensional surface described in step 1 is a parabola curvature surface or a double parabola curvature surface.

3. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The polygonal through hole described in step one is rectangular, circular, triangular or pentagonal; the aperture range of the polygonal through hole is 100 μm to 600 μm; the polygonal cross section described in step one is a circular cross section or a rectangular cross section.

4. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The material of the electrode substrate required for the three-dimensional electrolytic hydrogen production functional electrode described in step three is a polymer photocurable resin; the material of the gas control grid required for the three-dimensional electrolytic hydrogen production functional electrode described in step three is a polymer photocurable resin.

5. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The illumination time described in step 4 is 3 minutes to 5 minutes.

6. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that In step 5, the cobalt-nickel-phosphorus alloy catalyst is deposited on the electrode substrate by chemical plating, which is specifically completed in the following steps: ①, immerse the cured electrode substrate in anhydrous ethanol for ultrasonic treatment for 10 minutes, repeat the above operation twice to remove oxides and impurities on the surface of the electrode substrate, and obtain a cleaned electrode substrate; immerse the cleaned electrode substrate in a mixture of 39.6mL water, 400μL of 37% dilute hydrochloric acid and 0.426g SnCl2 at a temperature of 45°C for 10 minutes. The electrode is sensitized in this step to obtain a sensitized electrode substrate; ② Rinse the sensitized electrode substrate 3 to 5 times with deionized water, then dry it, and then put it into a mixture of 40 mL of water, 100 μL of 37% dilute hydrochloric acid and 0.005 g of PdCl2 at 45 ° C for 20 minutes to complete the activation process and obtain an activated electrode substrate; ③. Add 0.657g NiSO4·6H2O and 0.703g CoSO4·7H2O to 80mL deionized water, stir evenly with a magnetic stirrer, then add 2.94g C6H5Na3O7 and 3.45g C4H4Na2O6 and continue stirring, then add 6.6g (NH4)2SO4 and 2.12g NaH2PO2 to the solution, and finally add NaOH to adjust the pH value of the solution to 8.0-9.

0. After stirring evenly, add deionized water to a beaker with a measuring cylinder, dilute to 100mL, and heat the solution to 70℃ for 10min to obtain a deposition solution; ④. Immerse the activated electrode substrate in the deposition solution for 3 to 5 minutes, take it out and dry it to obtain an electrode substrate with a cobalt-nickel-phosphorus alloy catalyst deposited thereon.

7. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that In step 5, the thickness of the cobalt-nickel-phosphorus alloy catalyst on the surface of the electrode substrate is 50 nm to 200 nm.

8. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The concentration of the hydrochloric acid in step six is ​​0.1 mol / L; the soaking time in step six is ​​10 min to 15 min.

9. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that In step 7, the thickness of nano-silicon dioxide on the surface of the gas manipulation grid is 500nm-1000nm; the drying temperature in step 7 is 60°C-70°C, and the drying time is 10h-12h.

10. The method for preparing a three-dimensional electrolytic hydrogen production functional electrode based on wettability gradient and unidirectional bubble control according to claim 1, characterized in that The distance between the surface of the electrode substrate on which the cobalt-nickel-phosphorus alloy catalyst is deposited in step eight and the gas manipulation grid with an asymmetric wettability gradient is 200 μm to 600 μm.

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