Tin-based hollow fiber gas permeation and dispersion electrode and manufacturing method and application thereof

Abstract

The invention discloses a tin-based hollow fiber gas permeation and dispersion electrode and a manufacturing method and application thereof, and belongs to the field of carbon dioxide catalytic reduction. The tin-based hollow fiber gas permeation and dispersion electrode comprises a nickel electrode substrate with a porous wall body, and the surface of the nickel electrode substrate is loaded with a catalytic structure of a mixture of Sn4 (OH) 6Cl2 and SnO2. According to the electrode, active sites with high selective adsorption capacity are formed at the interface position between Sn < 2 + > and Sn < 4 + >, so that the selectivity and yield of formic acid in the catalytic reduction process of carbon dioxide under high current density are effectively improved.

Description

Technical Field

[0001] This invention belongs to the field of carbon dioxide catalytic reduction, specifically relating to a tin-based hollow fiber gas permeation electrode, its manufacturing method, and its application. Background Technology

[0002] Electrocatalytic reduction of carbon dioxide is a key pathway for converting the greenhouse gas carbon dioxide into high-value-added chemicals and achieving carbon recycling. It belongs to the cutting-edge field of intersection between energy catalysis and chemical engineering. Under the current "dual carbon" goal, this technology has attracted significant attention due to its ability to directly store renewable energy electricity as chemical energy. Among these technologies, formic acid, being a widely used chemical raw material and a potential liquid hydrogen carrier, has garnered industry attention due to its synthesis via the catalytic reduction of carbon dioxide.

[0003] Patents CN118814195A, CN118272865A, CN118461036A, etc., propose several different hollow electrodes for the catalytic reduction of carbon dioxide. However, these technical solutions are affected by the physicochemical properties of the electrodes themselves, resulting in complex composition of the reduction products and insufficient selectivity for formic acid, which increases the cost of separation and purification in subsequent industrial applications.

[0004] Patent CN118292036A discloses a Sn nanocatalyst capable of selectively reducing carbon dioxide to formic acid. However, the catalyst in this technology is limited by its morphology, requiring the slurry to be coated onto the surface of a conductive electrode for use. During the catalytic reduction process, when the current density exceeds 1 A / cm², [further issues arise]. -2 The Faraday efficiency of formic acid begins to decline, limiting its potential for large-scale industrial production.

[0005] Therefore, providing a more efficient carbon dioxide reduction electrode is of positive significance for the promotion of carbon dioxide catalytic reduction technology. Summary of the Invention

[0006] The purpose of this invention is to provide a tin-based hollow fiber gas permeation electrode to improve the efficiency of carbon dioxide catalytic reduction of formic acid. This invention also provides a method for manufacturing the tin-based hollow fiber gas permeation electrode, a carbon dioxide catalytic reduction apparatus, and a carbon dioxide catalytic reduction method.

[0007] According to one aspect of the present invention, a tin-based hollow fiber gas permeation electrode is provided, the electrode comprising a nickel electrode substrate configured in a tubular shape, the wall of the nickel electrode substrate having a porous structure, and a catalytic structure loaded on the surface of the nickel electrode substrate, the catalytic structure being a mixture of Sn4(OH)6Cl2 and SnO2.

[0008] In this electrode, the catalytic structure includes Sn.2+ With Sn 4+ Two different valence states of Sn, with the active center located at Sn 2 + With Sn 4+ At the interface between the sites, this non-uniform structure creates a unique valence gradient. Its electronic structure, coordination environment, and chemical bonding state enhance the active sites' catalytic reduction of carbon dioxide. The key intermediates were subjected to more selective adsorption, thus achieving better selectivity for the catalytic reduction product formic acid.

[0009] Furthermore, in some embodiments, the catalytic structure is configured as a strip structure grown perpendicular to the surface of the nickel electrode substrate.

[0010] Furthermore, in some embodiments, the molar ratio of Sn4(OH)6Cl2 to SnO2 in the catalytic structure is 0.5-2.

[0011] According to another aspect of the present invention, a method for manufacturing a tin-based hollow fiber gas permeation electrode is provided, for manufacturing the hollow fiber gas permeation electrode provided in any of the foregoing embodiments, the method specifically includes the following steps:

[0012] Step a): The nickel electrode substrate is prepared using a phase transformation method;

[0013] Step b): Provide a first solution at a ratio of 27 mL to 33 mL of pure water per 1 g SnCl2·2H2O, and introduce argon and air into the first solution while continuously stirring;

[0014] Step c): Adjust the pH of the first solution to 2-5 to obtain the second solution;

[0015] Step d): Immerse the nickel electrode substrate in the second solution and stir at room temperature for 1-24 hours. Then remove, clean and dry to obtain the finished tin-based hollow fiber gas permeation electrode.

[0016] By controlling the ratio of argon to air to adjust the oxidizing properties in the second solution, a composite catalytic structure of Sn4(OH)6Cl2 and SnO2 mixed on a nickel electrode substrate can be selectively formed, thereby producing an electrode with higher selectivity for formic acid.

[0017] Furthermore, in some embodiments, in step b), the volume ratio of argon gas to air is 0.5-2.

[0018] Furthermore, in some embodiments, in step b), argon and air are alternately introduced for a total duration of 4-12 hours.

[0019] Furthermore, in some embodiments, in step c), the method for adjusting the pH value is to add an alkaline solution to the first solution, wherein the alkaline solution is one of ammonia water, NaOH solution, and KOH solution.

[0020] Furthermore, in some embodiments, in step c), the concentration of the alkaline solution is 1M-10M.

[0021] Further, in some embodiments, the process of manufacturing the nickel electrode substrate in step a) is as follows: providing Ni-containing powder, which includes pure Ni powder, NiO powder, or Ni-containing organic compound powder; mixing the Ni-containing powder with a binder and an organic solvent and ball milling to obtain a Ni-containing slurry; using pure water as the core liquid, injecting the Ni-containing slurry into water using a spinneret to obtain a tubular soft body; cleaning, shaping, and drying the tubular soft body to obtain a green body; calcining the green body in an oxidizing atmosphere to remove organic matter therein to obtain a nickel electrode blank; and reducing the nickel electrode blank in a reducing atmosphere to obtain the nickel electrode substrate.

[0022] Further, in some embodiments, in step a), the adhesive includes one of polyethersulfone (PES), polyvinylpyrrolidone (PVP), polystyrene (PS), polyethyleneimine (PEI), polyethylene (PE), polypropylene (PP), polycarbonate (PC), and polyamide (PA); the organic solvent includes one of N-methyl-2-pyrrolidone (NMP), N,N-dimethylamide (DMF), N,N-diethylformamide (DEF), and dimethyl sulfoxide (DMSO); in the Ni-containing slurry, by weight, Ni accounts for 10%-30%, the adhesive accounts for 5%-15%, and the organic solvent accounts for 60%-85%.

[0023] Further, in some embodiments, in step a), the oxidizing atmosphere is air, the green body is calcined in the oxidizing atmosphere at a temperature of 200℃-600℃ for a time of 1h-30h; the reducing atmosphere is hydrogen or a mixture of hydrogen and argon, the reduction treatment temperature is 200℃-600℃ for a time of 1h-30h.

[0024] Furthermore, in some embodiments, in step d), before immersing the nickel electrode substrate into the second solution, the nickel electrode is acid-washed to remove the surface oxide layer.

[0025] According to another embodiment of the present invention, a carbon dioxide catalytic reduction device is provided, the device comprising a cathode, an anode, a reference electrode, a reaction cell, and a conductive gas pipe connected to a carbon dioxide source, wherein the cathode is a tin-based hollow fiber gas permeation electrode provided in any of the preceding embodiments, and the cathode is fixedly connected to the conductive gas pipe such that the interior of the cathode is connected to the conductive gas pipe.

[0026] Furthermore, in some embodiments, the anode is a platinum electrode, the reference electrode is an Ag / AgCl electrode, the reaction cell includes a cathode cell and an anode cell, the cathode cell and the anode cell are isolated by an ion exchange membrane, the cathode and the reference electrode are immersed in the cathode cell, and the anode is immersed in the anode cell.

[0027] Furthermore, in some embodiments, the conductive vent pipe is configured as a copper pipe, and the pipe wall of the conductive vent pipe is provided with a through hole that matches the outer diameter of the cathode. The cathode is fixed in the through hole by conductive adhesive.

[0028] Furthermore, in some embodiments, the cathode cell contains a cathode electrolyte, the solute of which is one or a combination of several selected from KCl, NaCl, Na2SO4, K2SO4, KBr, NaBr, NaOH, KOH, Na2CO3, NaHCO3, KHCO3, and K2CO3; the anode cell contains an anolyte, the solute of which is one or a combination of several selected from KHCO3, K2SO4, NaHCO3, and Na2SO4.

[0029] According to another aspect of the present invention, a method for catalytic reduction of carbon dioxide is provided. This method employs the carbon dioxide catalytic reduction apparatus provided in any of the foregoing embodiments, wherein the cathode and the anode are respectively immersed in an electrolyte, and carbon dioxide is introduced into the conductive gas inlet pipe to form a three-phase interface on the cathode surface; wherein a voltage of -1V vs RHE to -10V vs RHE and a current density of 1mA / cm² are applied to the cathode. 2 -4000mA / cm 2 .

[0030] Furthermore, in some embodiments, the flow rate of carbon dioxide is 0.5 mL / min-1000 mL / min, and the reaction temperature is 5℃-80℃. Attached Figure Description

[0031] Figure 1 This is a cross-sectional photograph of a tin-based hollow fiber gas-permeable electrode in one embodiment;

[0032] Figure 2This is an electron microscope image of the microstructure of a tin-based hollow fiber gas-permeable electrode in one embodiment;

[0033] Figure 3 This is a cross-sectional photograph of the nickel electrode substrate in one embodiment;

[0034] Figure 4 This is an electron microscope image of the microstructure of a nickel electrode substrate in one embodiment;

[0035] Figure 5 The X-ray photoelectron spectra of Sn 3d in the examples and comparative examples are shown below.

[0036] Figure 6 The X-ray photoelectron spectra of O 1s in the examples and comparative examples are shown.

[0037] The purpose of the above figures is to provide a detailed description of the invention so that those skilled in the art can understand the technical concept of the invention, and not to limit the invention. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings.

[0039] The term "embodiment" as used herein means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment herein. The phrase appearing in various places in the specification does not necessarily refer to the same embodiment, nor is it limited to mutually exclusive, independent, or alternative embodiments. Those skilled in the art will understand that the embodiments herein can be combined with other embodiments without causing structural conflicts.

[0040] In this document, terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating relative importance or limiting the number, specific order, or primary / secondary relationship of the described technical features. In this document, "multiple" means at least two.

[0041] With the continuous development of new energy technologies and carbon recovery technologies, the carbon dioxide catalytic reduction process based on new energy sources has shown promising application prospects. Using wind power, photovoltaic power, and bioelectricity as energy sources, carbon dioxide is converted into industrial raw materials through chemical catalysis, which can effectively save energy and reduce emissions while improving the comprehensive utilization efficiency of new energy sources. Among the products of carbon dioxide catalytic reduction, formic acid not only has a wide range of industrial applications but is also considered a potential liquid hydrogen carrier; therefore, the technical route of catalytic reduction of carbon dioxide to formic acid has attracted attention. Currently, tin-based materials have relatively high cost advantages and high formic acid selectivity, and are considered to have good application prospects.

[0042] However, the industrial application of carbon dioxide catalytic reduction is still constrained by current technological levels. On the one hand, the low solubility of carbon dioxide in water limits the mass transfer rate during the catalytic reduction process, making it difficult to improve the overall current density and conversion efficiency. On the other hand, tin materials themselves have low mechanical strength, making it difficult to fabricate them as electrode structures on their own. Furthermore, highly active nano-tin-based catalysts are prone to particle agglomeration or exfoliation on conventional planar electrodes, leading to a reduction in active sites and decreased stability. Simultaneously, in existing technologies, at high reaction rates, there is intense competition between the hydrogen evolution side reaction and the target reaction, resulting in a significant decrease in the Faradaic efficiency of formic acid at high current densities. These factors collectively restrict the industrial application of carbon dioxide catalytic reduction for the production of formic acid.

[0043] To overcome the above-mentioned shortcomings of the prior art, one embodiment of the present invention provides a tin-based hollow fiber gas permeation electrode. This electrode effectively improves the mass transfer efficiency in the catalytic reaction process by loading a tin-based catalytic structure onto a nickel hollow fiber. On the other hand, the distribution of multivalent Sn in the catalytic structure forms highly selective active sites, which effectively improves the selective adsorption capacity for intermediate products, especially maintaining high selectivity for formic acid under high current density reaction conditions.

[0044] Specifically, the electrode structure is as follows: Figure 1 As shown, its substrate is a tubular nickel electrode substrate with a porous structure in its walls. These porous structures can serve as diffusion channels for carbon dioxide during the reaction process and effectively increase the area of ​​the reaction interface. Figure 2 The nickel electrode substrate of this electrode has catalytic structures loaded on its surface. These catalytic structures are three-dimensional, hierarchical nanoribbon structures grown perpendicular to the porous surface, and their composition is a mixture of Sn₄(OH)₆Cl₂ and SnO₂. In different embodiments, depending on the reaction conditions, the molar ratio of Sn₄(OH)₆Cl₂ to SnO₂ is 0.5-2. These catalytic structures greatly increase the specific surface area of ​​the electrode, provide more active sites, and offer abundant channels for the transport of reactants and products, effectively improving the reaction efficiency.

[0045] In this electrode, the catalytic structure includes Sn. 2+ With Sn 4+ Two different valence states of Sn, with the active center located at Sn 2 + With Sn 4+ At the interface between the sites, this non-uniform structure creates a unique valence gradient. Its electronic structure, coordination environment, and chemical bonding state enhance the active sites' catalytic reduction of carbon dioxide. The key intermediates were subjected to more selective adsorption, thus achieving better selectivity for the catalytic reduction product formic acid.

[0046] This electrode can be manufactured using the method for manufacturing a tin-based hollow fiber gas permeation electrode provided in another aspect of the present invention. The specific process is as follows:

[0047] Step a): Prepare the nickel electrode substrate using the phase inversion method.

[0048] Specifically, in a preferred embodiment, Ni-containing powder is used as the raw material. The Ni-containing powder is mixed with a binder and an organic solvent and ball-milled to obtain a uniform Ni-containing slurry. The Ni-containing powder can be pure Ni powder, NiO powder, or Ni-containing organic compound powder; the binder can be polyethersulfone (PES), polyvinylpyrrolidone (PVP), polystyrene (PS), polyethyleneimine (PEI), polyethylene (PE), polypropylene (PP), polycarbonate (PC), or polyamide (PA); the organic solvent can be N-methyl-2-pyrrolidone (NMP), N,N-dimethylamide (DMF), N,N-diethylformamide (DEF), or dimethyl sulfoxide (DMSO). In the slurry, by weight, Ni accounts for 10%-30%, the binder accounts for 5%-15%, and the organic solvent accounts for 60%-85%.

[0049] Using a syringe pump, a slurry is propelled through a stainless steel hollow spinneret. The spinneret wicking fluid is pure water, and the coagulation fluid is water, such as tap water. The distance between the spinneret and the surface of the coagulation fluid is 0.5cm-5cm. After passing through the spinneret, the slurry enters the coagulation fluid and solidifies into a hollow fiber tubular soft body. The tubular soft body is continuously soaked in sufficient water or continuously rinsed with running water for at least 12 hours to exchange and remove excess organic solvents. In a preferred embodiment, the cleaning process continues for at least 24 hours.

[0050] After cleaning, the tubular soft body is removed, straightened, and fixed in shape, then naturally dried in air to obtain a green blank. The green blank is then calcined in an oxidizing atmosphere to remove organic components, yielding a nickel electrode blank. The cross-sectional structure of the obtained nickel electrode blank is shown below. Figure 3 As shown, its microstructure is as follows Figure 4 As shown.

[0051] In a preferred embodiment, the oxidizing atmosphere is air, the calcination temperature is 200℃-600℃, the calcination time is 1h-30h, and the gas flow rate is 10mL / min-700mL / min. In a further preferred embodiment, the calcination temperature is 400℃-600℃, the calcination time is 5h-10h, and the gas flow rate is 200mL / min-600mL / min. Finally, the nickel electrode blank is reduced in a reducing atmosphere to obtain the nickel electrode substrate. In a preferred embodiment, the reducing atmosphere is hydrogen or a mixture of hydrogen and argon, the reduction treatment temperature is 200℃-600℃, the heating time is 1h-30h, and the reducing gas flow rate is 10mL / min-700mL / min. In a further preferred embodiment, the reduction treatment temperature is 400℃-600℃, the heating time is 5h-10h, and the reducing gas flow rate is 200mL / min-600mL / min. During the calcination and reduction process, the initial temperature is set to 20℃-30℃, and the heating rate during the heating process is 1℃ / min-30℃ / min, which is controlled to 1℃ / min-10℃ / min in the preferred embodiment.

[0052] Step b): Prepare the first solution by dissolving 1g of SnCl2·2H2O in 27mL-33mL of pure water. After adding SnCl2·2H2O to the pure water, stir continuously for 4h-12h, and introduce argon and air during the stirring process. In a preferred embodiment, the volume ratio of argon to air is 0.5-2. The volume ratio of the introduced gases is controlled by alternating the introduction of argon and air. For example, during 6h of stirring, argon is introduced for 4h first, followed by air at the same flow rate for 2h. By adjusting the ratio of argon to air, the proportion of different valence states of Sn can be adjusted. The specific reaction processes are as follows: 4SnCl2+6H2O→Sn4(OH)6Cl2+6HCl; 2SnCl2+2H2O+O2→2SnO2+4HCl.

[0053] Step c): Inject an alkaline solution into the first solution to adjust its pH to 2-5, thus obtaining the second solution. Specifically, the alkaline solution can be ammonia, NaOH solution, or KOH solution, with a concentration range of 1M-10M, and in the preferred embodiment, 1M-5M.

[0054] Step d): Immerse the nickel electrode substrate in the second solution and stir at room temperature for 1-24 hours. Then remove, clean, and dry to obtain the tin-based hollow fiber gas permeation electrode product. In a preferred embodiment, the stirring time is 2-10 hours.

[0055] In a preferred embodiment, before immersing the nickel electrode substrate in the second solution, it is first subjected to acid pickling to remove the surface oxide layer. Specifically, it is immersed in an acidic solution for ultrasonic treatment. The acidic solution uses HCl, H2SO4, or HNO3 with a concentration of 0.1M-5M, and the treatment time is 0.1h-5h. In a further preferred embodiment, the concentration of the acidic solution is 0.5M-2M, and the treatment time is 0.5h-2h. Subsequently, it is ultrasonically cleaned with acetone, ethanol, and deionized water, and then dried after removal.

[0056] Another embodiment of the present invention provides a carbon dioxide catalytic reduction device. The device includes a cathode, an anode, a reference electrode, a reaction cell, and a conductive vent pipe connected to a carbon dioxide source. The cathode is a tin-based hollow fiber gas permeation electrode as described in the previous embodiment, and is fixedly connected to the conductive vent pipe, with the hollow portion of the cathode communicating internally with the conductive vent pipe to allow carbon dioxide to diffuse outward through the electrode wall. The anode material is a platinum electrode, specifically a platinum wire or platinum mesh. Ag / AgCl is used as the reference electrode. The reaction cell includes a cathode cell and an anode cell separated by an ion exchange membrane. The cathode and reference electrode are disposed within the cathode cell, and the anode is disposed within the anode cell. Electrolytes are injected into both the cathode cell and the anode cell. Specifically, in a preferred embodiment, the solute in the cathode electrolyte is one or a combination of several selected from KCl, NaCl, Na2SO4, K2SO4, KBr, NaBr, NaOH, KOH, Na2CO3, NaHCO3, KHCO3, and K2CO3; the solute in the anolyte can be one or a combination of several selected from KHCO3, K2SO4, NaHCO3, and Na2SO4; and the concentration range is 0.1M-5M depending on the solubility of the solute.

[0057] Another embodiment of the present invention provides a method for the catalytic reduction of carbon dioxide, which uses the carbon dioxide catalytic reduction apparatus provided in the foregoing embodiments, and the specific process is as follows:

[0058] A carbon dioxide catalytic reduction device was constructed. Cathode electrolyte and anolyte were injected into the cathode and anode cells, respectively. The cathode and reference electrode were immersed in the cathode cell, and the anode was immersed in the anode cell. Carbon dioxide was introduced into a conductive vent pipe, allowing it to diffuse through the cathode wall into the cathode cell, thus forming a three-phase interface of electrode, carbon dioxide, and electrolyte on the cathode surface. A voltage was applied to the cathode, ranging from -1V vs RHE to -10V vs RHE, with a current density of 1 mA / cm². 2 -4000mA / cm 2The reaction involves the catalytic reduction of carbon dioxide. In a preferred embodiment, the voltage range is -0.35V vs RHE to -3.5V vs RHE, the carbon dioxide flow rate is 0.5mL / min to 1000mL / min, the reaction temperature is 5℃ to 80℃, and the reaction pressure is 0.1bar to 10bar; in a further preferred embodiment, the flow rate is 1mL / min to 100mL / min, the reaction temperature is 20℃ to 60℃, and the reaction pressure is 0.1bar to 5bar.

[0059] In one embodiment of the present invention, the tin-based hollow fiber permeable electrode is manufactured by the following process:

[0060] Step a): The nickel electrode substrate is manufactured using a phase transformation method;

[0061] Step b): Dissolve 1 g SnCl2·2H2O in 30 mL of deionized water and stir continuously for 6 hours to prepare the first solution. During the stirring process, argon gas and air are alternately introduced.

[0062] Step c): Add ammonia water dropwise to the first solution to adjust the pH value to 3, thus obtaining the second solution.

[0063] Step d): The nickel electrode is ultrasonically cleaned with HCl solution to remove the oxide layer on its surface. After cleaning and drying, it is immersed in a second solution and stirred. After removal, it is rinsed with deionized water and dried in an oven at 40°C to obtain the finished electrode.

[0064] In step b), argon gas is first introduced for 3 hours, followed by air for 3 hours, to obtain electrode 1 with a molar ratio of Sn4(OH)6Cl2:SnO2 of 1; argon gas is first introduced for 4 hours, followed by air for 2 hours, to obtain electrode 2 with a molar ratio of Sn4(OH)6Cl2:SnO2 of 2; and argon gas is first introduced for 2 hours, followed by air for 4 hours, to obtain electrode 3 with a molar ratio of Sn4(OH)6Cl2:SnO2 of 0.5.

[0065] In one set of comparative examples, the electrodes were manufactured using the same process as in the examples, except that: in step b), argon gas was introduced for 6 hours to obtain electrode 4, which has a catalytic structure of Sn4(OH)6Cl2; and in step b), air was introduced for 6 hours to obtain electrode 5, which has a catalytic structure of SnO2.

[0066] X-ray photoelectron spectroscopy analysis was performed on electrodes 1 to 5 respectively, and the results are as follows: Figure 5 and Figure 6 As shown.

[0067] Carbon dioxide catalytic reduction experimental devices were constructed using the electrodes prepared in the above examples and comparative examples. Carbon dioxide catalytic reduction experiments were conducted using electrodes 1 to 5 under different conditions. The experimental conditions and results are shown in Table 1. A 2M KHCO3 solution was used as the cathode electrolyte in the experiments.

[0068] Table 1 Electrocatalytic Reduction Experiment of Carbon Dioxide

[0069]

[0070] Carbon dioxide is injected into the hollow electrode through a conductive vent tube. The carbon dioxide diffuses into the solution through the porous electrode wall and undergoes a reduction reaction at the active sites. Analysis of the reaction products from the above examples and comparative examples revealed that only carbon dioxide and hydrogen were detected as reduction products. The overall Faraday efficiency was [not specified] at current densities of 0.5 A / m². 2 -4A / cm 2 The results were basically consistent within the range, approaching 100%. Analysis of the above experimental results shows that, under the same conditions, the formic acid selectivity and formic acid yield of electrodes 1, 2, and 3 provided in the examples are superior to those of electrodes 4 and 5 provided in the comparative examples. Among them, electrode 1, using Sn4(OH)6Cl2:SnO2=1, exhibited the lowest onset potential, and its yield increased even when the current density reached 3.5 A / cm². 2 Formic acid selectivity remained at 93%, and formic acid yield reached 61 mmol·h. −1 ·cm -2 Exceeding other electrodes at 4A / cm 2 The data below shows that the electrode with the Sn4(OH)6Cl2 and SnO2 composite catalytic structure provided in the embodiments of the present invention has higher formic acid selective catalytic efficiency and yield. Among them, when Sn4(OH)6Cl2:SnO2 is close to 1, specifically in the range of 0.9-1.1, it has significantly optimal catalytic reduction efficiency.

[0071] The purpose of the above embodiments is to provide a further detailed description of the present invention in conjunction with the accompanying drawings, so that those skilled in the art can understand the technical concept of the present invention. Within the scope of the present invention, optimization or equivalent substitution of the technical features involved, as well as combination of implementation methods in different embodiments without causing structural and principle conflicts, all fall within the protection scope of the present invention.

Claims

1. A tin-based hollow fiber gas permeation electrode, characterized in that, The invention includes a nickel electrode substrate, which is configured in a tubular shape and has a porous wall structure. The surface of the nickel electrode substrate is loaded with a catalytic structure, which is a mixture of Sn4(OH)6Cl2 and SnO2.

2. The tin-based hollow fiber gas permeation electrode according to claim 1, characterized in that, The catalytic structure is configured as a strip structure grown perpendicular to the surface of the nickel electrode substrate.

3. The tin-based hollow fiber gas permeation electrode according to claim 1 or 2, characterized in that, In the catalytic structure, the molar ratio of Sn4(OH)6Cl2 to SnO2 is 0.5-2.

4. A method for manufacturing a tin-based hollow fiber gas permeation electrode, characterized in that, A method for manufacturing a tin-based hollow fiber gas-permeable electrode as described in any one of claims 1 to 3, comprising the following steps: Step a): The nickel electrode substrate is prepared using a phase transformation method; Step b): Provide a first solution at a ratio of 27 mL to 33 mL of pure water per 1 g SnCl2·2H2O, and introduce argon and air into the first solution while continuously stirring; Step c): Adjust the pH of the first solution to 2-5 to obtain the second solution; Step d): Immerse the nickel electrode substrate in the second solution and stir at room temperature for 1-24 hours. Then remove, clean and dry to obtain the finished tin-based hollow fiber gas permeation electrode.

5. The method for manufacturing the tin-based hollow fiber gas-permeable electrode according to claim 4, characterized in that, In step b), the volume ratio of argon gas to air is 0.5-2.

6. The method for manufacturing the tin-based hollow fiber gas-permeable electrode according to claim 5, characterized in that, In step b), argon and air are alternately introduced for a total duration of 4-12 hours.

7. The method for manufacturing a tin-based hollow fiber gas-permeable electrode according to claim 4, characterized in that, In step c), the method for adjusting the pH value is to add an alkaline solution to the first solution, wherein the alkaline solution is one of ammonia water, NaOH solution, or KOH solution.

8. The method for manufacturing a tin-based hollow fiber gas-permeable electrode according to claim 7, characterized in that, In step c), the concentration of the alkaline solution is 1M-10M.

9. A method for manufacturing a tin-based hollow fiber gas-permeable electrode according to any one of claims 4 to 8, characterized in that, In step a), the process of manufacturing the nickel electrode substrate is as follows: Ni-containing powder is provided, including pure Ni powder, NiO powder, or Ni-containing organic compound powder; the Ni-containing powder is mixed with a binder and an organic solvent and ball-milled to obtain a Ni-containing slurry; using pure water as the core liquid, the Ni-containing slurry is injected into water using a spinneret to obtain a tubular soft body; the tubular soft body is cleaned, shaped, and dried to obtain a green body; the green body is calcined in an oxidizing atmosphere to remove organic matter therein to obtain a nickel electrode blank; the nickel electrode blank is reduced in a reducing atmosphere to obtain the nickel electrode substrate.

10. The method for manufacturing a tin-based hollow fiber gas-permeable electrode according to claim 9, characterized in that, In step a), the adhesive includes one of polyethersulfone, polyvinylpyrrolidone, polystyrene, polyethyleneimine, polyethylene, polypropylene, polycarbonate, and polyamide; the organic solvent includes one of N-methyl-2-pyrrolidone, N,N-dimethylamide, N,N-diethylformamide, and dimethyl sulfoxide; in the Ni-containing slurry, by weight ratio, Ni accounts for 10%-30%, the adhesive accounts for 5%-15%, and the organic solvent accounts for 60%-85%.

11. The method for manufacturing a tin-based hollow fiber gas-permeable electrode according to claim 9, characterized in that, In step a), the oxidizing atmosphere is air, the green body is calcined in the oxidizing atmosphere at a temperature of 200℃-600℃ for a time of 1h-30h, and the reducing atmosphere is hydrogen or a mixture of hydrogen and argon, the reduction treatment temperature is 200℃-600℃ for a time of 1h-30h.

12. The method for manufacturing a tin-based hollow fiber gas-permeable electrode according to claim 9, characterized in that, In step d), before immersing the nickel electrode substrate into the second solution, the nickel electrode is acid-washed to remove the surface oxide layer.

13. A carbon dioxide catalytic reduction device, comprising a cathode, an anode, a reference electrode, and a reaction cell, characterized in that, The carbon dioxide catalytic reduction device includes a conductive vent pipe connected to a carbon dioxide source; the cathode is a tin-based hollow fiber gas permeation electrode as described in any one of claims 1 to 3, and the cathode is fixedly connected to the conductive vent pipe, so that the interior of the cathode is connected to the conductive vent pipe.

14. The carbon dioxide catalytic reduction apparatus according to claim 13, characterized in that, The anode is a platinum electrode, the reference electrode is an Ag / AgCl electrode, the reaction cell includes a cathode cell and an anode cell, the cathode cell and the anode cell are isolated by an ion exchange membrane, the cathode and the reference electrode are disposed in the cathode cell, and the anode is disposed in the anode cell.

15. The carbon dioxide catalytic reduction apparatus according to claim 13 or 14, characterized in that, The conductive vent pipe is configured as a copper pipe, and the pipe wall of the conductive vent pipe is provided with a through hole that matches the outer diameter of the cathode. The cathode is fixed in the through hole by conductive adhesive.

16. The carbon dioxide catalytic reduction apparatus according to claim 14, characterized in that, The cathode cell contains a cathode electrolyte, the solute of which is one or a combination of several selected from KCl, NaCl, Na2SO4, K2SO4, KBr, NaBr, NaOH, KOH, Na2CO3, NaHCO3, KHCO3, and K2CO3; the anode cell contains an anolyte, the solute of which is one or a combination of several selected from KHCO3, K2SO4, NaHCO3, and Na2SO4.

17. A method for the catalytic reduction of carbon dioxide, characterized in that, Using the carbon dioxide catalytic reduction apparatus as described in any one of claims 13 to 16, the cathode and the anode are respectively immersed in an electrolyte, and carbon dioxide is introduced into the conductive gas inlet pipe to form a three-phase interface on the cathode surface; wherein a voltage of -1V vs RHE to -10V vs RHE and a current density of 1mA / cm² are applied to the cathode. 2 -4000mA / cm 2 .

18. The carbon dioxide catalytic reduction method according to claim 17, characterized in that, The flow rate of carbon dioxide is 0.5 mL / min-1000 mL / min, and the reaction temperature is 5℃-80℃.

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