Carbon dioxide electroreduction membrane electrode and preparation method thereof
By combining the nano-scale cathode catalyst with dual hydrophobic effects and hydrophobic materials, the selectivity and stability of carbon dioxide electroreduction membrane electrodes in large-area and high-power applications are solved, and a breakthrough transformation in the efficient preparation of high-value-added compounds is achieved.
Patent Information
- Application Number
- CN202510720172.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-30
- Publication Date
- 2025-08-15
AI Technical Summary
The existing carbon dioxide electroreduction membrane electrodes have problems such as decreased selectivity and insufficient stability in large-area and high-power applications, making it difficult to achieve industrial-grade current density and efficient preparation of high-value-added compounds.
The nano-scale cathode catalyst is prepared by hydrothermal reaction and annealing treatment, and a hydrophobic material is coated on the cathode gas diffusion electrode to form a cathode gas diffusion electrode with dual hydrophobic effects. Combined with the porous structure of the nano-scale catalyst, the electrochemical active area is improved.
It significantly inhibits the hydrogen evolution reaction, improves the reaction selectivity of carbon dioxide, maintains good stability and Faraday efficiency, and can efficiently prepare single-carbon and multi-carbon compounds, with an annual output of up to 100 kg.
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of carbon dioxide electric reduction, and in particular to a carbon dioxide electric reduction membrane electrode and a preparation method thereof. Background Art
[0002] With the acceleration of global industrialization, the massive consumption of fossil fuels has triggered serious carbon emissions, leading to a series of environmental crises such as global warming. To address this challenge, using clean electricity generated by renewable energy to convert CO2 into high-value-added chemicals and fuels through carbon dioxide electrochemical reduction (CO2RR) technology has become a promising solution.
[0003] Over the past few decades, CO2RR technology has made significant progress in catalyst design and reaction mechanism research, successfully producing a variety of products, including single-carbon (such as CO, formic acid, methane, and methanol) and multi-carbon (such as ethanol, ethylene, and acetone) compounds. However, despite these advances, a significant gap remains between basic research and practical application of CO2RR technology. Achieving industrial-scale current density and stability remains a pressing challenge.
[0004] During the electrochemical reduction of carbon dioxide, the current density in an aqueous environment is limited to about 100 mA / cm due to the limited solubility of carbon dioxide in water and the limited mass transfer. 2 The emergence of membrane electrode assemblies (MEAs) has brought hope for solving this problem. By directly connecting the cathode and anode to the membrane, it effectively avoids unnecessary electrolyte resistance, increases the carbon dioxide concentration at the gas-liquid-solid reaction boundary on the cathode catalyst surface, inhibits the hydrogen evolution reaction, and improves the reaction selectivity of carbon dioxide, enabling industrial-grade current density to be achieved at a higher efficiency. However, in actual production applications, when large-area membrane electrodes and high-power electroreduction devices are required to meet industrial production needs, problems such as reduced selectivity, shortened life, and insufficient stability due to the size-enlargement effect will arise.
[0005] Therefore, developing a carbon dioxide electroreduction membrane electrode with high carbon dioxide reaction selectivity and good stability has important scientific significance and application value.
[0006] The statements herein merely provide background information related to the present invention and do not necessarily constitute prior art. Summary of the Invention
[0007] The objective of the present invention is to provide a carbon dioxide electroreduction membrane electrode, the cathode gas diffusion electrode surface of which has a dual hydrophobic effect, which can significantly improve the reaction selectivity of carbon dioxide; when the membrane electrode is applied to a carbon dioxide electroreduction device, it can efficiently prepare single-carbon and / or multi-carbon compounds while maintaining good stability and Faraday efficiency.
[0008] In order to achieve the above objectives, the present invention provides a method for preparing a carbon dioxide electroreduction membrane electrode, the method comprising:
[0009] Step 1: adding a metal precursor to a long-chain alkyl solution, causing a hydrothermal reaction, and then annealing to obtain a nanoscale cathode catalyst;
[0010] Step 2: dispersing the anode catalyst and the anion exchange resin in a first solvent to obtain an anode catalyst slurry; dispersing the nanoscale cathode catalyst and the anion exchange resin in the first solvent to obtain a nanoscale cathode catalyst slurry;
[0011] Step 3, coating the anode catalyst slurry and the nano-scale cathode catalyst slurry on the anode gas diffusion layer and the cathode gas diffusion layer respectively to obtain an anode gas diffusion electrode and a cathode gas diffusion electrode;
[0012] Step 4, dispersing carbon powder and polytetrafluoroethylene in a second solvent and then coating the solvent on the cathode gas diffusion electrode to obtain a hydrophobic cathode gas diffusion electrode;
[0013] Step 5: stacking the hydrophobic cathode gas diffusion electrode, the anion exchange membrane, and the anode gas diffusion electrode in sequence, and hot pressing them to obtain a carbon dioxide electroreduction membrane electrode.
[0014] Optionally, in step 1, the temperature of the hydrothermal reaction is 150°C-200°C, and the temperature of the annealing is 200°C-300°C.
[0015] Optionally, in step 1, the long-chain alkyl solution comprises any one of dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl; and the metal precursor comprises any one of a copper precursor and a silver precursor.
[0016] Optionally, in step 2, the anode catalyst comprises any one of iridium oxide, ruthenium dioxide, nickel-iron oxide, and nickel-iron alloy; the nanoscale cathode catalyst comprises any one of nanoscale Cu2O and nanoscale Ag2O; and the particle size of the nanoscale cathode catalyst is 50nm-100nm.
[0017] Optionally, in step 2, the anion exchange resin comprises QAPPT, SUSTAINION, PiperlON, One or more of; the first solvent comprises one or more of anhydrous methanol, anhydrous ethanol, isopropanol, and deionized water.
[0018] Optionally, in step 3, the anode gas diffusion layer comprises any one of titanium felt, titanium mesh, and sintered porous titanium plate; and the cathode gas diffusion layer comprises any one of carbon paper, carbon cloth, and carbon fiber plate.
[0019] Optionally, in step 4, the second solvent comprises one or more of anhydrous methanol, anhydrous ethanol, and deionized water.
[0020] Optionally, after step 4 and before step 5, the method further comprises immersing the anion exchange membrane in an alkaline solution, wherein the alkaline solution comprises one or more of LiOH, KOH, NaOH, and CsOH, and the immersion time is 24 hours to 36 hours.
[0021] Optionally, in step 5, the hot pressing pressure is 1 MPa-3 MPa, the hot pressing temperature is 40° C.-70° C., and the hot pressing time is 5 min-10 min.
[0022] The present invention also provides a use of a carbon dioxide electric reduction membrane electrode obtained by the above-mentioned preparation method, wherein the carbon dioxide electric reduction membrane electrode is used to form a carbon dioxide electric reduction device.
[0023] Compared with the prior art, the technical solution of the present invention has at least the following beneficial effects:
[0024] 1) The present invention first prepares a nanoscale cathode catalyst with surface hydrophobicity through a hydrothermal reaction and annealing treatment, and then coats the nanoscale cathode catalyst on a cathode gas diffusion layer to obtain a cathode gas diffusion electrode. Then, a hydrophobic material (carbon powder and polytetrafluoroethylene) is coated on the cathode gas diffusion electrode to obtain a hydrophobic cathode gas diffusion electrode. Due to the synergistic effect of the nanoscale cathode catalyst with surface hydrophobicity and the hydrophobic material, the surface of the hydrophobic cathode gas diffusion electrode has a dual hydrophobic effect, which can greatly inhibit the hydrogen evolution reaction and significantly improve the reaction selectivity of carbon dioxide, thereby solving the problem of decreased selectivity caused by the size magnification effect. At the same time, the catalytic layer is composed of the nanoscale cathode catalyst and has a porous structure, and the specific surface area is increased, which can significantly increase the electrochemical active area of the membrane electrode.
[0025] 2) Furthermore, when the membrane electrode prepared by the present invention (using nano-scale Ag2O cathode catalyst) is applied to a carbon dioxide electroreduction device, the 2 It can operate stably for more than 100 hours at a current density of 1000 nm, maintaining good stability and Faradaic efficiency (reflecting the ability to generate the target product in the electrochemical reaction).
[0026] 3) Furthermore, when the membrane electrode prepared by the present invention is applied to a carbon dioxide electroreduction device, it can efficiently prepare single-carbon and / or multi-carbon compounds, with an annual output of hundreds of kilograms for a single device, which is expected to bring about a breakthrough in the large-scale and precise preparation of high-value-added chemical products from carbon dioxide. BRIEF DESCRIPTION OF THE DRAWINGS
[0027] Figure 1 The present invention is a flow chart of the method for preparing the carbon dioxide electroreduction membrane electrode.
[0028] Figure 2 The current-voltage curves of the membrane electrodes prepared in Examples 1-4 of the present invention when applied to a carbon dioxide electroreduction device are shown.
[0029] Figure 3 The membrane electrode prepared in Examples 1-4 of the present invention is applied to a carbon dioxide electroreduction device at 0.5 A / cm 2 Selected distribution of gas components under current density.
[0030] Figure 4 The membrane electrode prepared in Example 2 of the present invention is applied to a carbon dioxide electroreduction device at 0.5 A / cm 2 Stability curve and Faraday efficiency curve after 100h of continuous operation at the same current density. DETAILED DESCRIPTION
[0031] The following is a further detailed description of the preparation method of the carbon dioxide electroreduction membrane electrode proposed in the present invention in conjunction with the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer. It should be noted that the drawings are in a very simplified form and use non-precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the present invention. In order to make the purposes, features and advantages of the present invention more obvious and easy to understand, please refer to the drawings. It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions for the implementation of the present invention, so they have no technical significance. Any modification of the structure, change in the proportional relationship or adjustment of the size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.
[0032] As described in the background technology, the membrane electrode assembly directly connects the cathode and anode to the membrane, effectively avoiding unnecessary electrolyte resistance, increasing the carbon dioxide concentration at the gas-liquid-solid reaction boundary on the cathode catalyst surface, inhibiting the hydrogen evolution reaction, and improving the reaction selectivity of carbon dioxide. It can achieve industrial-grade current density at a higher efficiency. However, in actual applications, when large-area, high-power membrane electrodes and electroreduction devices are required to meet industrial production needs, it will bring about problems such as decreased selectivity, shortened life, and insufficient stability due to the size magnification effect.
[0033] In order to solve the above problems, the present invention prepares a new membrane electrode, firstly prepares a nano-scale cathode catalyst with surface hydrophobicity through hydrothermal reaction and annealing treatment, and then coats the nano-scale cathode catalyst on the cathode gas diffusion layer to obtain a cathode gas diffusion electrode, and then coats the cathode gas diffusion electrode with a hydrophobic material to obtain a hydrophobic cathode gas diffusion electrode. The surface of the hydrophobic cathode gas diffusion electrode has a dual hydrophobic effect, which can greatly inhibit the hydrogen evolution reaction and significantly improve the reaction selectivity of carbon dioxide. At the same time, when the membrane electrode is used in a carbon dioxide electroreduction device, it has high power and good stability and Faraday efficiency. Specifically, if Figure 1 As shown, the present invention provides a method for preparing a carbon dioxide electroreduction membrane electrode, the method comprising:
[0034] Step 1: Add a metal precursor to a long-chain alkyl solution, undergo a hydrothermal reaction, and then anneal to obtain a nano-scale cathode catalyst.
[0035] A long-chain alkyl solution and a metal precursor undergo a hydrothermal reaction and are annealed in an air atmosphere. Air favors the formation of metal oxides, while annealing facilitates the formation of nanoparticles, ultimately yielding a nanoscale cathode catalyst. The nanoscale cathode catalyst has a particle size of 50-100 nm and a hydrophobic surface, which inhibits the hydrogen evolution reaction and improves the selectivity of the carbon dioxide reaction.
[0036] In some embodiments, the temperature of the hydrothermal reaction is 150°C-200°C, and the temperature of the annealing is 200°C-300°C.
[0037] In some embodiments, the long-chain alkyl solution comprises any one of dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl; and the metal precursor comprises any one of a copper precursor and a silver precursor.
[0038] Step 2: Dispersing the anode catalyst and the anion exchange resin in a first solvent to obtain an anode catalyst slurry; dispersing the nanoscale cathode catalyst and the anion exchange resin in the first solvent to obtain a nanoscale cathode catalyst slurry.
[0039] The anode catalyst and anion exchange resin are dispersed in the first solvent and stirred, and then dispersed using a high-speed shearing device with a shear speed of 15,000-20,000 rpm, and finally ultrasonicated for 1-3 hours to obtain an anode catalyst slurry. The preparation method of the nano-scale cathode catalyst slurry is the same.
[0040] In some embodiments, the anode catalyst comprises any one of iridium oxide, ruthenium dioxide, nickel-iron oxide, and nickel-iron alloy; the nanoscale cathode catalyst comprises any one of nanoscale Cu2O and nanoscale Ag2O.
[0041] In some embodiments, the anion exchange resin comprises QAPPT, SUSTAINION, PiperlON, One or more of; the first solvent comprises anhydrous methanol, anhydrous ethanol, isopropanol, one or more of deionized water.
[0042] Step 3: coating the anode catalyst slurry and the nano-scale cathode catalyst slurry on the anode gas diffusion layer and the cathode gas diffusion layer respectively to obtain an anode gas diffusion electrode and a cathode gas diffusion electrode.
[0043] The anode catalyst slurry and the nano-scale cathode catalyst slurry are uniformly coated on the anode gas diffusion layer and the cathode gas diffusion layer respectively by spraying, slit coating, screen printing and the like, and the anode gas diffusion electrode and the cathode gas diffusion electrode are obtained after drying.
[0044] In some embodiments, the anode gas diffusion layer comprises any one of titanium felt, titanium mesh, and sintered porous titanium plate. To reduce the contact resistance of the anode gas diffusion layer, a layer of platinum is plated on its surface. The thickness of the platinum coating is 0.15 μm-3 μm. The porosity of the anode gas diffusion layer is 0.3-0.8, and the pore size is 20 μm-200 μm. The catalyst loading of the anode gas diffusion electrode is 1 mg / cm 2 -5mg / cm 2 .
[0045] In some embodiments, the cathode gas diffusion layer comprises any one of carbon paper, carbon cloth, and carbon fiber sheet. The cathode gas diffusion layer has a porosity of 0.7-0.9 and a pore size of 10 μm-100 μm. The catalyst loading of the cathode gas diffusion electrode is 0.5 mg / cm 2 -3mg / cm 2 .
[0046] Step 4: dispersing carbon powder and polytetrafluoroethylene in a second solvent and then coating the dispersed carbon powder and polytetrafluoroethylene on the cathode gas diffusion electrode to obtain a hydrophobic cathode gas diffusion electrode.
[0047] A certain amount of carbon powder and polytetrafluoroethylene powder are dispersed in a second solvent and ultrasonically treated for 30-60 minutes, and then uniformly coated on the surface of the cathode gas diffusion electrode covered with the catalyst, and dried to obtain a hydrophobic cathode gas diffusion electrode. Carbon powder is a non-polar carbon skeleton, lacks hydrophilic groups, and has strong hydrophobicity. Polytetrafluoroethylene is a symmetrical carbon-fluorine structure with extremely low surface energy and strong hydrophobicity. The two are used in combination to make the surface of the cathode gas diffusion electrode hydrophobic, and the surface of the cathode gas diffusion electrode is also coated with a hydrophobic nano-scale cathode catalyst, so that the surface of the cathode gas diffusion electrode has a dual hydrophobic effect, which can greatly inhibit the hydrogen evolution reaction and significantly improve the reaction selectivity of carbon dioxide. In addition, the catalytic layer is composed of nano-scale cathode catalysts and has a porous structure, and the specific surface area is increased, which significantly improves the electrochemical active area of the membrane electrode. The electrochemical active area of the membrane electrode is 160 cm 2 -450cm 2 .
[0048] In some embodiments, the porosity of the carbon powder is 0.5-0.7, the pore size is 0.3 μm-0.8 μm, and the particle size of the polytetrafluoroethylene powder is 0.05 μm-0.15 μm. The carbon powder loading of the hydrophobic cathode gas diffusion electrode is 0.3 mg / cm 2 -0.8mg / cm 2 , the polytetrafluoroethylene loading is 0.8 mg / cm 2 -2.5mg / cm 2 .
[0049] In some embodiments, the second solvent comprises one or more of anhydrous methanol, anhydrous ethanol, and deionized water.
[0050] After step 4, the anion exchange membrane is cut into a desired shape and immersed in an alkaline solution in an oven at 60° C. to 80° C. for 24 h to 36 h to fully activate the anion exchange membrane.
[0051] In some embodiments, the anion exchange membrane comprises QAPPT, PiperlON, The thickness of the anion exchange membrane is 40 μm-200 μm. The alkaline solution comprises one or more of LiOH, KOH, NaOH, and CsOH.
[0052] Step 5: stacking the hydrophobic cathode gas diffusion electrode, the anion exchange membrane, and the anode gas diffusion electrode in sequence, and hot pressing them to obtain a carbon dioxide electroreduction membrane electrode.
[0053] A hydrophobic cathode gas diffusion electrode (with the catalyst-coated side facing upward), a cathode protection frame, an anion exchange membrane, an anode protection frame, and an anode gas diffusion electrode are stacked in sequence on a flat plate, and hot pressed for 5 minutes to 10 minutes at a pressure of 1 MPa to 3 MPa and a temperature of 40°C to 70°C to obtain a carbon dioxide electroreduction membrane electrode.
[0054] In some embodiments, the material of the cathode protection frame and the anode protection frame includes any one of polyethylene naphthalate (PEN), polyetherimide (PEI), polyimide (PI), and sulfonated polyetheretherketone (sPEEK), which functions to protect the diffusion electrode from damage.
[0055] Example 1
[0056] In step 1, the copper precursor, copper nitrate, was dissolved in a hexadecyl solution, stirred evenly, and then transferred to a hydrothermal reactor for a hydrothermal reaction at 180°C for 24 hours. After completion of the reaction, the reaction product was removed, washed three times with deionized water and three times with anhydrous ethanol, centrifuged, and dried at 60°C for 12 hours. The dried product was annealed in a tube furnace at 250°C for 2 hours to obtain a nanoscale Cu2O cathode catalyst with a particle size of 75 nm.
[0057] Step 2: Disperse iridium oxide and QAPPT in anhydrous ethanol at a mass ratio of 1000:1 and stir, then disperse for 60 minutes using a high-speed shearing device with a shear speed of 15,000 rpm, and finally ultrasonicate for 1 hour to obtain an anode catalyst slurry; disperse the nanoscale Cu2O cathode catalyst and QAPPT prepared in step 1 at a mass ratio of 1000:1 in anhydrous ethanol and stir, then disperse for 60 minutes using a high-speed shearing device with a shear speed of 15,000 rpm, and finally ultrasonicate for 1 hour to obtain a nanoscale Cu2O cathode catalyst slurry.
[0058] Step 3: Use spraying to evenly coat the anode catalyst slurry and nano-scale Cu2O cathode catalyst slurry prepared in step 2 on platinum-coated titanium felt and carbon paper, respectively, and dry them at 80°C for 2 hours to obtain an anode gas diffusion electrode and a cathode gas diffusion electrode. The catalyst loading of the anode gas diffusion electrode is 2 mg / cm 2 The catalyst loading of the cathode gas diffusion electrode is 0.8 mg / cm 2 .
[0059] Step 4: Disperse carbon powder and polytetrafluoroethylene powder in a mass ratio of 2:5 in anhydrous ethanol and ultrasonically apply the powder to the surface of the cathode gas diffusion electrode prepared in step 3, which is coated with the catalyst, and then dry at 80°C for 2 hours to obtain a hydrophobic cathode gas diffusion electrode. The carbon powder loading of the hydrophobic cathode gas diffusion electrode is 0.5 mg / cm 2 , the polytetrafluoroethylene loading is 1.5 mg / cm2 .
[0060] Step 5: Cut the anion exchange membrane QAPPT into 17cm*20cm size, soak it in 1M KOH solution in a 60°C oven for 24h to fully activate the anion exchange membrane, and wash the activated anion exchange membrane with deionized water until it is neutral and set aside.
[0061] Step 6: stack the hydrophobic cathode gas diffusion electrode prepared in step 4 (with the catalyst-coated side facing up), the PI cathode protection frame, the anion exchange membrane in step 5, the PI anode protection frame, and the anode gas diffusion electrode prepared in step 3 on the flat plate in sequence, and hot press at a pressure of 3 MPa and a temperature of 70°C for 8 minutes to obtain a carbon dioxide electroreduction membrane electrode.
[0062] Example 2
[0063] The preparation method of the carbon dioxide electroreduction membrane electrode is the same as that in Example 1, except that the copper precursor copper nitrate in step 1 is replaced by the silver precursor silver nitrate.
[0064] Example 3
[0065] The preparation method of the carbon dioxide electroreduction membrane electrode is the same as that of Example 1, except that the mass ratio of 1000:1 in step 2 is replaced by a mass ratio of 200:1.
[0066] Example 4
[0067] The preparation method of the carbon dioxide electroreduction membrane electrode is the same as that of Example 1, except that the mass ratio of 1000:1 in step 2 is replaced by a mass ratio of 100:1.
[0068] The CO2 electroreduction membrane electrode prepared in Examples 1-4 was assembled with bipolar plates, insulating plates, and end plates to form a CO2 electroreduction device and tested. A 0.1M KOH solution was passed through the anode at a rate of 1 L / min, and CO2 gas with a stoichiometric ratio of 1.5 was passed through the cathode. The test temperature was 25°C.
[0069] The current-voltage curves of the above membrane electrodes were measured using a constant current test method, such as Figure 2 As shown, when the current density is constant, the mass of the anode / cathode catalyst in Example 1 is the largest, the voltage is the largest, and the power of the carbon dioxide electroreduction device is the largest, indicating that improving the mass of the anode / cathode catalyst is beneficial to increasing the power of the carbon dioxide electroreduction device. In addition, the voltage obtained using the nanoscale Ag2O cathode catalyst (Example 2) is lower than that obtained using the nanoscale Cu2O cathode catalyst (Examples 1, 3, and 4), indicating that using the nanoscale Cu2O cathode catalyst is beneficial to increasing the power of the carbon dioxide electroreduction device.
[0070] At 0.5A / cm2 The tail gas products were collected at a current density of , and the gas components were detected using a Shimadzu GC17A gas chromatograph. The distribution of the gas components was as follows: Figure 3 As shown, when using a nanoscale Ag2O cathode catalyst (Example 2), the H2 content generated at the cathode is only 10%, while the CO content (single-carbon compounds) generated is as high as 90%, indicating that the hydrogen evolution reaction is greatly suppressed and the reaction selectivity of carbon dioxide to single-carbon compounds is significantly improved. When using a nanoscale Cu2O cathode catalyst (Examples 1, 3, and 4), the carbon dioxide reduction reaction (primarily forming multi-carbon compounds) is slightly more than the hydrogen evolution reaction, but there is no significant difference between the two, indicating that the reaction selectivity of carbon dioxide to multi-carbon compounds is not high. At the same time, the mass of the catalyst has little effect on the reaction selectivity of carbon dioxide.
[0071] The membrane electrode prepared in Test Example 2 was applied to a carbon dioxide electroreduction device at 0.5 A / cm 2 The stability and Faradaic efficiency of the device were measured under a current density of 100 h. Figure 4 As shown in the figure, the CO2 electroreduction device maintains good stability and Faradaic efficiency as the operating time increases.
[0072] In summary, the cathode gas diffusion electrode surface of the membrane electrode prepared by the present invention has a dual hydrophobic effect, which can greatly inhibit the hydrogen evolution reaction and significantly improve the reaction selectivity of carbon dioxide; when the membrane electrode is applied to the carbon dioxide electroreduction device, it can efficiently prepare single-carbon and / or multi-carbon compounds while maintaining good stability and Faraday efficiency. The annual output of a single device reaches hundreds of kilograms, which is expected to bring about a breakthrough change in the large-scale and precise preparation of high-value-added chemical products from carbon dioxide.
[0073] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.
[0074] Although the present invention has been described in detail through the above preferred embodiments, it should be understood that the above description is not intended to limit the present invention. After reading the above description, various modifications and substitutions of the present invention will become apparent to those skilled in the art. Therefore, the scope of protection of the present invention should be defined by the appended claims.
Claims
1. A method for preparing a carbon dioxide electroreduction membrane electrode, characterized in that: The method includes: Step 1: adding a metal precursor to a long-chain alkyl solution, causing a hydrothermal reaction, and then annealing to obtain a nanoscale cathode catalyst; Step 2, dispersing the anode catalyst and the anion exchange resin in a first solvent to obtain an anode catalyst slurry; dispersing the nanoscale cathode catalyst and anion exchange resin in a first solvent to obtain a nanoscale cathode catalyst slurry; Step 3, coating the anode catalyst slurry and the nano-scale cathode catalyst slurry on the anode gas diffusion layer and the cathode gas diffusion layer respectively to obtain an anode gas diffusion electrode and a cathode gas diffusion electrode; Step 4, dispersing carbon powder and polytetrafluoroethylene in a second solvent and then coating the solvent on the cathode gas diffusion electrode to obtain a hydrophobic cathode gas diffusion electrode; Step 5: stacking the hydrophobic cathode gas diffusion electrode, the anion exchange membrane, and the anode gas diffusion electrode in sequence, and hot pressing them to obtain a carbon dioxide electroreduction membrane electrode.
2. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 1, the temperature of the hydrothermal reaction is 150°C-200°C, and the temperature of the annealing is 200°C-300°C.
3. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 1, the long-chain alkyl solution includes any one of dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, and octadecyl; and the metal precursor includes any one of a copper precursor and a silver precursor.
4. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 2, the anode catalyst comprises any one of iridium oxide, ruthenium dioxide, nickel-iron oxide, and nickel-iron alloy; the nanoscale cathode catalyst comprises any one of nanoscale Cu2O and nanoscale Ag2O; and the particle size of the nanoscale cathode catalyst is 50nm-100nm.
5. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 2, the anion exchange resin comprises QAPPT, SUSTAINION, PiperlON, One or more of; the first solvent comprises one or more of anhydrous methanol, anhydrous ethanol, isopropanol, and deionized water.
6. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 3, the anode gas diffusion layer comprises any one of titanium felt, titanium mesh, and sintered porous titanium plate; the cathode gas diffusion layer comprises any one of carbon paper, carbon cloth, and carbon fiber plate.
7. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 4, the second solvent comprises one or more of anhydrous methanol, anhydrous ethanol, and deionized water.
8. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: After step 4 and before step 5, the anion exchange membrane is further immersed in an alkaline solution, wherein the alkaline solution comprises one or more of LiOH, KOH, NaOH, and CsOH, and the immersion time is 24 hours to 36 hours.
9. The method for preparing a carbon dioxide electroreduction membrane electrode according to claim 1, wherein: In step 5, the hot pressing pressure is 1 MPa-3 MPa, the hot pressing temperature is 40° C.-70° C., and the hot pressing time is 5 min-10 min.
10. Use of a carbon dioxide electroreduction membrane electrode obtained by the preparation method according to any one of claims 1 to 9, characterized in that: The carbon dioxide electric reduction membrane electrode is used to form a carbon dioxide electric reduction device.