A method for preparing carbon-supported transition metal single-atom materials and an electrolysis apparatus

Abstract

This application discloses a method for preparing carbon-supported transition metal single-atom materials. The material is a transition metal single-atom-anchored fluorine and nitrogen-co-doped carbon nanosheet electrocatalyst (M-CNF SACs). This type of material has a two-dimensional porous nanosheet structure. The nickel single-atom-anchored fluorine and nitrogen-co-doped porous carbon nanosheets (Ni-CNF SACs) are used for electrocatalyzing the carbon dioxide reduction reaction (CO2RR), exhibiting high catalytic activity, high selectivity, and excellent stability. The device includes an anode electrode, a cathode electrode, a cation exchange membrane, an anode electrolyte, and a cathode electrolyte. The cathode catalyst is Ni-CNF SACs coated on carbon paper, and the cathode electrolyte is a CO2-saturated potassium bicarbonate solution. The anode catalyst is a three-dimensional porous cobalt diselenide catalyst (CoSe2 / CC) grown in situ on carbon cloth, and the anode electrolyte is an alkaline solution containing glycerol.

Description

Technical Field

[0001] This application relates to a method for preparing a carbon material-supported transition metal single-atom material and its application in an electrolytic carbon dioxide device coupled with glycerol oxidation, belonging to the fields of inorganic catalyst materials and electrochemical reduction of CO2 technology. Background Technology

[0002] The massive consumption of fossil fuels has led to a year-on-year increase in atmospheric CO2 concentration, disrupting the dynamic carbon cycle balance between the biosphere, Earth, air, and water. This has resulted in a series of environmental problems and seriously threatens human survival and development. With more and more electricity coming from unlimited renewable energy sources, utilizing electrochemical conversion technology to transform CO2 into valuable fuel or feedstock molecules is an effective strategy for reducing atmospheric CO2 concentration. However, the commercial application of electrochemical CO2 reduction (CO2RR) still faces challenges such as low product selectivity, high catalyst and electrode costs, high electrolysis energy consumption, and high energy consumption and low value of the anode oxygen evolution reaction. Therefore, developing low-cost catalysts with high activity, high selectivity, and good stability for electrochemical CO2 reduction, while simultaneously finding an oxidation reaction with lower oxidation potential and certain value to replace OER, can reduce the energy consumption of CO2 electrolysis and enhance the value of the anode reaction.

[0003] Metal-anchored carbon-doped single-atom materials possess unique electronic and geometric structures, exhibiting excellent stability and catalytic activity during catalysis. However, the synthesis of current carbon-based single-atom catalysts faces challenges due to complex preparation processes and difficulties in large-scale production. Therefore, developing efficient and rapid methods for preparing single-atom catalysts with superior performance for efficient electrocatalytic CO2 reduction has attracted significant attention. Furthermore, glycerol is an abundant and inexpensive platform molecule that can be readily converted into high-value chemicals such as dihydroxyacetone (DHA), glyceric acid, glyceraldehyde, glycolic acid, and formic acid through the electrochemical oxidation of glycerol (GOR). Therefore, coupling GOR into CO2 electrolysis, with its lower oxidation potential replacing OER, can not only effectively reduce the energy consumption of CO2 electrolysis but also further enhance its application value. Summary of the Invention

[0004] According to one aspect of this application, a method for preparing a transition metal single-atom material supported on a fluorine-nitrogen co-doped carbon material is provided. The fluorine-nitrogen co-doped carbon material supported on a nickel single-atom material exhibits good catalytic performance as an electrocatalyst for the electrochemical carbon dioxide reduction reaction, demonstrating high catalytic efficiency and good stability. The preparation method for this type of material is simple and can be mass-produced.

[0005] The fluorine and nitrogen co-doped carbon material carrying transition metal single-atom material is characterized in that the transition metal single atoms are anchored on F and N co-doped porous carbon nanosheets.

[0006] The method for preparing the fluorine-nitrogen co-doped carbon material carrying transition metal single-atom materials is characterized by comprising the following steps:

[0007] a) Weigh a certain proportion of metal precursor, melamine and polytetrafluoroethylene micro powder (5μm) and grind them evenly in a mortar;

[0008] b) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (holding at 600℃ for 2 hours, then raising the temperature to 900℃ and holding for 1 hour) to obtain a transition metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0009] Optionally, in step a), the molar ratio of the metal precursor to melamine is 0.1–1:20–200; and the mass ratio of melamine to polytetrafluoroethylene is 3–15:6–20.

[0010] More preferably, the ratio of the metal precursor, melamine, and polytetrafluoroethylene powder added in step a) is:

[0011] 1 mmol metal precursor: 3 g melamine: 6 g polytetrafluoroethylene micro powder.

[0012] Preferably, in step b), the first stage of pyrolysis temperature is 500–600°C, and the holding time is 1–2 hours.

[0013] Preferably, the second pyrolysis temperature in step b) is 800–1000°C, and the holding time is 0.5–2 h.

[0014] More preferably, in step b), the first stage of pyrolysis temperature is 600℃ and the holding time is 2h.

[0015] More preferably, in step b), the second stage of pyrolysis is at a temperature of 900°C and the holding time is 1 hour.

[0016] According to one embodiment of this application, the preparation method of the metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material includes the following steps:

[0017] (1) Weigh a certain proportion of metal precursor, melamine and polytetrafluoroethylene micro powder (5μm) and grind them evenly in a mortar;

[0018] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (holding at 600℃ for 2 hours, then heating to 900℃ and holding for 1 hour) to obtain metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0019] According to another aspect of this application, an electrolytic carbon dioxide device coupled with glycerol oxidation is provided. This device utilizes the glycerol oxidation reaction (GOR) to replace the oxygen evolution reaction (OER), which can effectively reduce the energy consumption of CO2 electrolysis and further enhance the application value of CO2 electrolysis.

[0020] The device includes an anode electrode sheet, a cathode electrode sheet, a cation exchange membrane, an anode chamber electrolyte, and a cathode chamber electrolyte; wherein, the anode electrode sheet includes an anode catalyst, and the cathode catalyst is a nickel single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material;

[0021] The cathode electrolyte is a CO2-saturated KHCO3 solution, wherein the concentration of KHCO3 in the KHCO3 solution is 0.1–2.0 M; the anolyte is an alkaline solution containing glycerol.

[0022] Optionally, the electrolyte in the cathode chamber is a CO2-saturated KHCO3 solution.

[0023] Optionally, the concentration of KHCO3 in the CO2-saturated KHCO3 solution is 0.1–2.0 M.

[0024] Optionally, the concentration of KHCO3 in the CO2-saturated KHCO3 solution in the cathode chamber electrolyte is 2.0 M.

[0025] Optionally, the electrolyte in the anode chamber is a KOH solution containing glycerol.

[0026] Optionally, the pH of the electrolyte in the anode chamber is 13.0 to 14.5.

[0027] Optionally, the concentration of glycerol in the KOH solution containing glycerol in the anode chamber electrolyte is 2.0 M, and the pH of the electrolyte is 14.3.

[0028] Optionally, the cathode electrode is carbon paper coated with a cathode catalyst; the anode electrode is hydrophilic carbon cloth with a three-dimensional porous CoSe2 catalyst grown in situ.

[0029] Optionally, the loading area of ​​the cathode catalyst on the cathode electrode sheet accounts for 5% to 100% of the area of ​​the carbon paper.

[0030] Optionally, the loading area of ​​the cathode catalyst on the cathode electrode sheet accounts for 5% to 60% of the area of ​​the carbon paper.

[0031] Optionally, the area of ​​CoSe2 loaded on the anode electrode sheet accounts for 5% to 100% of the area of ​​the hydrophilic carbon cloth.

[0032] Optionally, the area of ​​CoSe2 loaded on the anode electrode sheet accounts for 50% to 60% of the area of ​​the hydrophilic carbon cloth.

[0033] Optionally, the carbon paper in the cathode electrode sheet has a size of 3cm × 3cm.

[0034] Optionally, the coating size of the cathode catalyst in the cathode electrode sheet is 1cm × 0.5 to 2cm.

[0035] Optionally, the cathode catalyst coating size in the cathode electrode sheet is 1cm × 1cm.

[0036] Optionally, the amount of anolyte catalyst coated in the anolyte electrode sheet is 1.0 to 10 mg.

[0037] Optionally, the amount of anolyte catalyst coated in the anolyte electrode sheet is 5 mg.

[0038] According to a specific embodiment of this application, the electrolytic carbon dioxide device coupled with glycerol oxidation is assembled by the following steps and methods:

[0039] Step 1: Preparation of Ni-CNF catalyst materials

[0040] (1) Weigh a certain proportion of nickel acetate monohydrate (0.1 mmol), melamine (3 g) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) and grind them evenly in a mortar;

[0041] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0042] Step 2: Prepare Ni-CNF electrode solution for electrochemical testing.

[0043] Take 3 mg of the Ni-CNF catalyst prepared in step one and disperse it in a mixed solution of 600 μL of water, ethanol, isopropanol and Nafion. Disperse it evenly by ultrasonication. Take 100 μL of the suspension and drop it into a 1 cm solution. 2 The carbon paper is dried naturally before being used for electrochemical testing.

[0044] Step 3: Prepare a CoSe2 / CC electrode for electrochemical testing of glycerol oxidation.

[0045] (1) Cut the commercial carbon cloth to the required size (1cm×1.2cm), boil it in 0.5MH2SO4 and 30%H2O2 at 80℃ for 1 hour, wash it with deionized water and dry it for later use.

[0046] (2) Prepare a cobalt nitrate solution with a molar concentration of 0.1M.

[0047] (3) A three-electrode system was used for electrodeposition, wherein the reference electrode was silver / silver chloride (Ag / AgCl) (saturated potassium chloride solution), the counter electrode was a graphite rod, and the working electrode was the hydrophilic carbon cloth obtained in step (1). Electrodeposition was performed using a constant voltage (-1.2V) relative to the silver / silver chloride (vs. Ag / AgCl) method, and the electrodeposition was maintained at this potential for 360s to obtain cobalt hydroxide nanosheets (Co(OH)2), which were then rinsed with deionized water and dried at 60°C.

[0048] (4) Place the Co(OH)2 obtained in step (3) in a ceramic boat and place it in the middle of a tube furnace. Weigh 0.5g of selenium powder in another ceramic boat and place it upstream of the gas flow in the tube furnace. Then, under the protective atmosphere of argon, raise the temperature from room temperature to 500℃ at a rate of 1℃ / min. Hold the temperature at 500℃ for one hour and then allow it to cool naturally to room temperature to obtain a three-dimensional porous cobalt selenide nanocatalyst (CoSe2 / CC) grown in situ on hydrophilic carbon cloth for electrochemical testing.

[0049] Step 4: Prepare a carbon dioxide electrolysis device for coupling glycerol oxidation by assembling Ni-CNF / CC and CoSe2 / CC electrodes.

[0050] 10 mg of the Ni-CNF catalyst prepared in step one was dispersed in 2 mL of mixed solution. 0.1 mL of the suspension was dropped onto carbon paper as the CO2RR cathode electrode. The CoSe2 / CC electrode prepared in step three was used as the anode electrode. An electrolytic carbon dioxide flow cell coupled with glycerol oxidation was assembled for electrochemical testing.

[0051] According to another aspect of this application, the electrolytic carbon dioxide apparatus coupled with glycerol oxidation is provided for use in a fuel cell.

[0052] In this application, the CO2 reduction reaction is abbreviated as CO2RR; the glycerol oxidation reaction is abbreviated as GOR; and the oxygen evolution reaction is abbreviated as OER.

[0053] In this application, carbon paper is abbreviated as CP; carbon cloth is abbreviated as CC.

[0054] The beneficial effects that this application may produce include at least the following:

[0055] 1) The material preparation scheme provided in this application is universal and can be used to synthesize other similar single-atom materials. As an electrocatalyst for CO2RR, it exhibits excellent catalytic activity, selectivity, and stability.

[0056] 2) The Ni-CNF single-atom material provided in this application serves as the cathode catalyst for carbon dioxide reduction in a CO2-saturated KHCO3 electrolyte, while CoSe2 / CC is used as the anode co-catalyst for glycerol oxidation in an alkaline electrolyte to assemble an energy-saving carbon dioxide electrolysis device coupled with glycerol oxidation. Only approximately 1.2V is required to drive the carbon dioxide electrolysis, and it can simultaneously achieve high-efficiency generation of carbon monoxide products at the cathode (carbon monoxide formation Faraday efficiency (FE)). CO (greater than 90%), high efficiency of formic acid product formation at the anode (formic acid formation Faraday efficiency (FE)). formate (Approximately 90%). Furthermore, the device is capable of operating at current densities of approximately 100 mA / cm². -2 Stable operation for 300 hours, FE CO and FE formate All reached 90%. The design of the preparation and application device for this material effectively reduced the energy consumption of CO2 electrolysis.

[0057] 3) The device for electrolyzing carbon dioxide provided in this application can not only convert carbon dioxide into value-added fuel molecules with low energy consumption, but also simultaneously enhance the value of the anode by converting glycerol, a byproduct of biodiesel, into value-added chemicals, and has broad application prospects in energy conversion and storage.

[0058] 4) The device for electrolyzing carbon dioxide provided in this application is not only inexpensive, easy to operate, and has excellent performance, but also has broad application prospects in energy conversion and storage. Attached Figure Description

[0059] Figure 1 Transmission electron microscopy (TEM) image of Ni-CNF;

[0060] Figure 2 This is a high-magnification transmission electron microscope image of Ni-CNF;

[0061] Figure 3 Aberration-corrected electron micrograph of Ni-CNF;

[0062] Figure 4 (a) is a transmission electron microscope image of Fe-CNF, and (b) is a high-magnification transmission electron microscope image.

[0063] Figure 5 (a) is a transmission electron microscope image of Mn-CNF, and (b) is a high-magnification transmission electron microscope image.

[0064] Figure 6(a) is a transmission electron microscope (TEM) image of Cu-CNF, and (b) is a high-magnification TEM image.

[0065] Figure 7 (a) is a transmission electron microscope image of Co-CNF, and (b) is a high-magnification transmission electron microscope image.

[0066] Figure 8 (a) is a transmission electron microscope image of Zn-CNF, and (b) is a high-magnification transmission electron microscope image.

[0067] Figure 9 CO2RR performance test of Ni-CNF in CO2-saturated 0.5M KHCO3 solution (CO formation Faraday efficiency at different potentials);

[0068] Figure 10 A schematic diagram of an electrolytic carbon dioxide testing apparatus coupled with glycerol oxidation;

[0069] Figure 11 Linear sweep voltammetric curves for the electrolysis of carbon dioxide coupled with glycerol oxidation and the conventional electrolysis of carbon dioxide coupled with oxygen evolution reaction;

[0070] Figure 12 This is a stability test diagram of an electrolytic cell for the coupled oxidation of glycerol and electrolysis of carbon dioxide. Detailed Implementation

[0071] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0072] The instruments used in this embodiment are: field emission transmission electron microscope (Tecnai F20), electrochemical workstation (CHI760, Shanghai Chenhua), and spherical aberration electron microscope (JEM-ARF200F).

[0073] Example 1: Preparation of single-atom material Ni-CNF samples

[0074] (1) Weigh a certain proportion of nickel acetate monohydrate (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) into a mortar and grind them evenly;

[0075] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Ni metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0076] Example 2: Preparation of Fe-CNF Single-Atom Material Samples

[0077] (1) Weigh a certain proportion of acetylacetone iron (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) into a mortar and grind them evenly;

[0078] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Fe metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0079] Example 3: Preparation of single-atom material Mn-CNF samples

[0080] (1) Weigh a certain proportion of manganese acetate tetrahydrate (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) into a mortar and grind them evenly;

[0081] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Mn metal single atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0082] Example 4: Preparation of Cu-CNF Single-Atom Material Samples

[0083] (1) Weigh a certain proportion of copper acetate dihydrate (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) into a mortar and grind them evenly;

[0084] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Cu metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0085] Example 5: Preparation of Co-CNF Samples (Single Atom Material)

[0086] (1) Weigh a certain proportion of cobalt acetate tetrahydrate (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) and grind them evenly in a mortar;

[0087] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Co metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0088] Example 6: Preparation of Zn-CNF Single-Atom Material Samples

[0089] (1) Weigh a certain proportion of zinc acetate dihydrate (0.1 mmol), melamine (0.2 mol) and polytetrafluoroethylene micro powder (5 μm) (6.0 g) into a mortar and grind them evenly;

[0090] (2) The initial mixture was placed in a tube furnace and subjected to a two-step pyrolysis method under an argon atmosphere (heating to 600°C at a rate of 2°C / min at room temperature, then holding at 600°C for 2 hours, then heating to 900°C at a rate of 2°C / min and holding for 1 hour, and then cooling naturally) to obtain Zn metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material.

[0091] Example 7 Characterization of single-atom material samples

[0092] The morphology of the Ni-CNF sample was examined using transmission electron microscopy. The results showed that the Ni-CNF sample had a wrinkled graphene nanosheet structure. Figure 1 The morphology of the Ni-CNF sample was further examined using transmission electron microscopy (TEM). The results showed that the Ni-CNF sample had a porous nanosheet structure. Figure 2 The presence of metal atoms was detected using spherical aberration electron microscopy. The results showed that Ni in the sample existed in the form of single atoms. Figure 3 ). Figure 4-7 For Fe-CNF ( Figure 4 Mn-CNF ( Figure 5 ), Cu-CNF ( Figure 6 ), Co-CNF ( Figure 7 ), Zn-CNF ( Figure 8 Transmission electron microscopy (TEM) images of the morphology of the materials show that all of them are porous nanosheet structures.

[0093] Example 8 Preparation of Ni-CNF / CC

[0094] The Ni-CNF single-atom material was used as a carbon dioxide reduction catalyst, loaded onto carbon paper, with a sample loading of 0.5 mg / cm² on the electrode surface. 2 The electrode obtained is Ni-CNF / CC.

[0095] Taking the Ni-CNF as an example, the specific steps for preparing the Ni-CNF / CC electrode are as follows: Take 3 mg of the synthesized sample and disperse it in 600 μL of a mixed solution of water, ethanol, isopropanol, and perfluorosulfonic acid (nafion) (volume ratio of water:ethanol:isopropanol:nafion = 9:6:3:2). Disperse the solution evenly using ultrasonication to form a suspension. Drop the suspension onto carbon paper (the area of ​​the carbon paper is 1 × 1.5 cm²). 2 The sample loading on the carbon paper electrode was set to 0.5 mg / cm³. 2 After natural drying, the electrode sheet for catalytic carbon dioxide reduction is obtained, denoted as Ni-CNF / CC.

[0096] Example 9 Electrochemical testing of Ni-CNF / CC electrode

[0097] The catalytic activity and selectivity of the Ni-CNF / CC electrode were tested. The carbon dioxide reduction reaction (CO2RR) was tested in CO2-saturated 0.5M KHCO3, and the distribution of catalytic carbon dioxide reduction products at different potentials was tested.

[0098] The results show that the Ni-CNF / CC electrode exhibits excellent CO2RR catalytic performance, achieving a Faradaic efficiency of over 90% for CO generation over a wide potential window. Figure 9 As shown, the excellent selectivity of the Ni-CNF / CC electrode for catalytic carbon dioxide reduction is demonstrated.

[0099] Example 10: Preparation of cathode electrode sheet for an electrolytic carbon dioxide apparatus coupled with glycerol oxidation

[0100] The Ni-CNF single-atom material was used as a carbon dioxide reduction catalyst, loaded onto carbon paper, with a sample loading of 0.5 mg / cm² on the electrode surface. 2 The electrode obtained is N1.

[0101] Taking the Ni-CNF as an example, the specific steps for preparing electrode N1 are as follows: Take 3 mg of the synthesized sample and disperse it in 600 μL of a mixed solution of water, ethanol, isopropanol, and perfluorosulfonic acid (nafion) (volume ratio of water:ethanol:isopropanol:nafion = 9:6:3:2). Sonicate the solution until it is uniformly dispersed to form a suspension. Take a drop of the suspension and drop it onto carbon paper (the area of ​​the carbon paper is 3×3 cm). 2 The area to be coated is 1×1cm in the middle of the carbon paper. 2 This resulted in a sample loading of 0.5 mg / cm² on the carbon paper electrode. 2 After natural drying, the cathode electrode for catalytic carbon dioxide reduction is obtained, denoted as N1.

[0102] Example 11: Preparation of a CoSe2 / CC electrode for electrochemical testing of glycerol oxidation.

[0103] (1) Cut the commercial carbon cloth to the required size (1cm×1.2cm), boil it in 0.5MH2SO4 and 30%H2O2 at 80℃ for 1 hour, wash it with deionized water and dry it for later use.

[0104] (2) Prepare a cobalt nitrate solution with a molar concentration of 0.1M.

[0105] (3) A three-electrode system was used for electrodeposition, wherein the reference electrode was silver / silver chloride (Ag / AgCl) (saturated potassium chloride solution), the counter electrode was a graphite rod, and the working electrode was the hydrophilic carbon cloth obtained in step (1). Electrodeposition was performed using a constant voltage (-1.2V) relative to the silver / silver chloride (vs. Ag / AgCl) method, and the electrodeposition was maintained at this potential for 360s to obtain cobalt hydroxide nanosheets (Co(OH)2), which were then rinsed with deionized water and dried at 60°C.

[0106] (4) Place the Co(OH)2 obtained in step (3) in a ceramic boat and place it in the middle of a tube furnace. Weigh 0.5g of selenium powder in another ceramic boat and place it upstream of the gas flow in the tube furnace. Then, under the protective atmosphere of argon, raise the temperature from room temperature to 500℃ at a rate of 1℃ / min. Hold the temperature at 500℃ for one hour and then let it cool naturally to room temperature to obtain a three-dimensional porous cobalt selenide nanocatalyst (CoSe2 / CC) grown in situ on hydrophilic carbon cloth. This is the anode electrode sheet, denoted as P1.

[0107] Example 12: Preparation of an electrolytic carbon dioxide apparatus E coupled with glycerol oxidation

[0108] An electrolytic carbon dioxide device coupled with glycerol oxidation, assembled with cathode electrode N1 and anode electrode P1 respectively, is denoted as E1. A schematic diagram of the electrolytic carbon dioxide device coupled with glycerol oxidation is shown below. Figure 10 As shown.

[0109] Taking cathode electrode N1 and anode electrode P1 as an example, the specific process is as follows:

[0110] Using N1 as the cathode electrode and P1 as the anode electrode, a proton exchange membrane separates the cathode and anode chambers. A cathode electrolyte is injected into the cathode chamber. The back of the carbon paper on the cathode electrode serves as a gas diffusion layer, through which CO2 reaches the catalyst surface for reaction. The CO2 flow rate is 100 mL / min. The side coated with the catalyst is in contact with the cathode electrolyte, which is a 2M KOH solution saturated with CO2, with a flow rate of 50 mL / min. An anolyte is injected into the anode chamber. The anolyte is a 2M KOH solution containing glycerol, with a glycerol concentration of 2 mol / L, and a flow rate of 50 mL / min.

[0111] The performance of E1 coupled with glycerol oxidation in the electrolysis of carbon dioxide was measured, and the results showed that the initial voltage of E1 was only about 1.2V. Figure 11 Furthermore, this device is capable of operating at current densities of approximately 100 mA / cm². -2 After 300 hours of stable operation, the carbon monoxide formation Faraday efficiency (FE) CO ) and formic acid formation Faraday efficiency (FE) formate All can reach 90% ( Figure 12 ).

[0112] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and all fall within the scope of the technical solution.

Claims

1. An electrolysis apparatus, comprising a cathode, characterized in that, The electrolysis device further includes an anode, an anode chamber, and a cathode chamber, with a diaphragm between the anode chamber and the cathode chamber; an electrocatalytic carbon dioxide reduction reaction is carried out on the cathode, and an electrocatalytic glycerol oxidation reaction is carried out on the anode; The anode is supported with a three-dimensional porous cobalt selenide catalyst; the preparation method of the three-dimensional porous cobalt selenide catalyst supported on the anode is as follows: the anode is electrodeposited in a solution containing cobalt ions to form cobalt hydroxide nanosheets on the anode; then the anode and selenium powder are heated and reacted under an inert atmosphere to obtain a three-dimensional porous cobalt selenide nanocatalyst grown in situ on the anode. The cathode is loaded with a cathode catalyst, which comprises a fluorine-nitrogen co-doped carbon material supporting a transition metal single-atom material. The preparation method of the fluorine-nitrogen co-doped carbon material supporting the transition metal single-atom material includes the following steps: a) Weigh the transition metal precursor, melamine, and polytetrafluoroethylene and grind them evenly in a mortar; the transition metal is selected from at least one of Mn, Fe, Co, Ni, Cu, and Zn; b) The mixture obtained from grinding in step a) is pyrolyzed under an inert atmosphere to obtain a transition metal single-atom anchored fluorine and nitrogen co-doped carbon porous nanosheet material, which is the fluorine and nitrogen co-doped carbon material carrying a transition metal single atom.

2. The electrolysis apparatus according to claim 1, characterized in that, The transition metal precursor includes at least one of nitrate, acetate, and acetylacetonate.

3. The electrolysis apparatus according to claim 1, characterized in that, In step a), the molar ratio of the transition metal precursor to melamine is 0.1~1:20~200; The mass ratio of melamine to polytetrafluoroethylene is 3~15:6~20.

4. The electrolysis apparatus according to claim 1, characterized in that, The pyrolysis method in step b) is as follows: keep the temperature at 500~600℃ for 1~2 hours, and then raise the temperature to 800~1000℃ and keep it at 0.5~2 hours.

5. The electrolysis apparatus according to claim 1, characterized in that, The cathode chamber contains a cathode electrolyte containing CO2, and the anode chamber contains an anolyte containing glycerol.

6. The electrolysis apparatus according to claim 5, characterized in that, The CO2-containing cathode electrolyte is a CO2-saturated bicarbonate solution.

7. The electrolysis apparatus according to claim 6, characterized in that, The concentration of bicarbonate in the CO2-containing cathode electrolyte is 0.1~2.0 M.

8. The electrolysis apparatus according to claim 5, characterized in that, The glycerol-containing anolyte has a glycerol concentration of 0.1-2 M and a pH of 13.0-14.

5.

9. The electrolysis apparatus according to claim 1, characterized in that, The cathode is obtained by coating a dispersion of a transition metal single-atom material carried by a fluorine and nitrogen co-doped carbon material onto carbon paper.

10. The electrolysis apparatus according to claim 9, characterized in that, The transition metal is nickel.

11. The electrolysis apparatus according to claim 9, characterized in that, The cathode catalyst has a loading area of ​​5% to 60% of the carbon paper area.

12. The electrolysis apparatus according to claim 9, characterized in that, The coating amount of cathode catalyst in the cathode is 0.1~1.0 mg / cm³. 2 .

13. The electrolysis apparatus according to claim 1, characterized in that, The anode is made of hydrophilic carbon cloth material.

14. The electrolysis apparatus according to claim 1, characterized in that, The area of ​​CoSe2 loaded on the anode accounts for 20% to 60% of the anode area.

15. The electrolysis apparatus according to claim 1, characterized in that, The amount of anolyte catalyst in the anode is 1.0~10 mg / cm³. 2 .

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