Metal-CO2 battery based on Cu-based nano amorphous alloy catalyst and preparation method of metal-CO2 battery
By regulating the electronic and geometric structures using Cu-based nano-amorphous alloy catalysts, the problem of slow Li2CO3 decomposition kinetics in metal-CO2 batteries was solved, thereby improving the battery's charge-discharge performance and cycle stability.
Patent Information
- Application Number
- CN202511672554.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-11-14
- Publication Date
- 2026-02-13
AI Technical Summary
The decomposition kinetics of Li2CO3 in metal-CO2 batteries are slow during charging, resulting in excessively high charging voltage, low battery energy efficiency, and poor cycle performance.
Cu-based nanocrystalline amorphous alloy catalysts were used to catalyze the CO2 reduction and Li2CO3 decomposition reactions on the positive electrode side of metal-CO2 batteries by alloying and controlling their electronic and geometric structures.
It increases the discharge voltage of metal-CO2 batteries, reduces the charging voltage, and improves charge-discharge energy efficiency and battery cycle life.
Smart Images
Figure CN121529073A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of metal-air batteries, in particular to a metal-CO2 battery based on a Cu-based nanometer amorphous alloy catalyst and a preparation method thereof. BACKGROUND
[0002] The widespread use of fossil fuel energy has led to a sharp increase in the concentration of carbon dioxide in the atmosphere, which in turn has triggered a series of problems such as global warming, ocean acidification and carbon cycle imbalance, seriously threatening the sustainable development of human society. In recent years, a number of carbon dioxide emission reduction and utilization technologies have developed rapidly. Among them, metal-CO2 batteries with CO2 as the positive active material have attracted much attention due to their excellent energy density.
[0003] Metal-CO2 batteries provide a new way to solve the problem of CO2 gas enrichment in the atmosphere. The positive electrode of the metal-CO2 battery can capture CO2 gas and convert it into clean electrical energy through electrochemical reaction, forming a double-channel solution of CO2 fixation and clean electrical energy output. However, metal-CO2 batteries still face many challenges in actual application. During the discharge process of the metal-CO2 battery, CO2 is reduced and lithium carbonate (Li2CO3) is formed as the discharge product. The decomposition kinetics of Li2CO3 is very slow during the charging process, resulting in a high charging voltage of the metal-CO2 battery, which leads to low energy efficiency and poor cycle performance of the battery. In order to solve the problem of slow decomposition kinetics of Li2CO3 during the charging process of the metal-CO2 battery, researchers have developed positive catalysts to improve the decomposition reaction rate of Li2CO3 or change the type of discharge product, thereby improving the charge and discharge performance of the metal-CO2 battery.
[0004] Copper (Cu) based nanomaterials have high electrical conductivity and exhibit excellent CO2 reduction performance and diverse product selectivity in aqueous solutions. However, the catalytic performance of Cu-based nanomaterials in metal-CO2 batteries in organic solution systems has not been fully studied and developed.
[0005] In addition, in the prior art, the performance of Cu-based nanomaterials is generally improved by alloying or oxide modification. In recent years, nanomaterials with amorphous structure have shown great potential in electrocatalysis and have exhibited superior performance. The surface of amorphous materials has a high degree of unsaturated atomic sites, which makes its disordered surface have more active sites and increases the reaction area. SUMMARY
[0006] Based on the problems of high charging voltage and poor cycle performance of the metal-CO2 battery in the prior art, the application provides a metal-CO2 battery based on a Cu-based nanometer amorphous alloy catalyst and a preparation method thereof, and the electronic structure and geometric structure of the Cu-based nanometer material are regulated by adopting an amorphous nanometer structure and an alloying method, so that the catalytic performance of the Cu-based nanometer material on CO2 reduction and Li2CO3 decomposition in the charging and discharging process of the metal-CO2 battery is improved.
[0007] The application adopts the following technical scheme: a Cu-based nanometer amorphous alloy catalyst, alloying elements of the Cu-based nanometer amorphous alloy include 3d transition group metals such as chromium (Cr), manganese (Mn) and vanadium (V); the composition of the Cu-based nanometer amorphous alloy catalyst is a binary or ternary or more nanometer alloy formed by the main element Cu and one or more of the alloying elements Cr, Mn and V, and the phase structure thereof is a long-range disordered amorphous crystal structure, and the morphology of the Cu-based nanometer amorphous alloy catalyst is irregular spherical nanoparticles.
[0008] As a preferred, the size of the nanometer spherical is 2-40 nanometers.
[0009] The application also provides a metal-CO2 battery based on the Cu-based nanometer amorphous alloy catalyst, the Cu-based nanometer amorphous alloy catalyst is used for catalyzing CO2 reduction and Li2CO3 decomposition reactions on the positive side of the metal-CO2 battery, the CO2 reduction corresponds to the discharging process of the metal-CO2 battery, and the Li2CO3 decomposition corresponds to the charging process of the metal-CO2 battery.
[0010] The discharging voltage of the metal-CO2 battery based on the Cu-based nanometer amorphous alloy catalyst is higher than that of the metal-CO2 battery based on a pure Cu nanometer amorphous catalyst, and the charging voltage of the metal-CO2 battery based on the Cu-based nanometer amorphous alloy catalyst is lower than that of the metal-CO2 battery based on the pure Cu nanometer amorphous catalyst.
[0011] As a preferred, the metal anode in the metal-CO2 battery includes but is not limited to metal lithium (Li) and metal sodium (Na).
[0012] The application also provides a preparation method of the Cu-based nanometer amorphous alloy catalyst, including the following steps:
[0013] Step 1, preparation of a carbon carrier suspension liquid: 40 mg of carbon black is dissolved in 40 mL of ethylene glycol, stirred for 10 min, ultrasonically treated for 30 min, and then stirred for 20 min to obtain a uniformly mixed suspension liquid ;
[0014] Step 2, preparation of metal precursor solution: 0.6-1.2 mmol CuCl2 and 0.6-0 mmol alloying metal salt were respectively taken and dissolved in 10 mL ethylene glycol, and a uniformly mixed solution was obtained after ultrasonic treatment for 30 min and stirring for 20 min The solution was added dropwise to the suspension to obtain a mixed solution ;
[0015] Step 3, preparation of tannic acid solution: 100-500 mg tannic acid was taken and added to 10 mL ethylene glycol, and a uniformly mixed solution was obtained after stirring for 10 min, ultrasonic treatment for 30 min and stirring for 20 min The solution was added dropwise to the mixed solution under stirring to obtain a solution ;
[0016] Step 4, preparation of NaOH solution: 0.4 g NaOH was taken and added to 10 mL deionized water to obtain a solution The solution was added to the solution and reacted for 10 min, and then Cu-based nanometer amorphous alloy catalyst was obtained by washing, centrifugation and drying.
[0017] As a preferred, the alloying metal salt is a single salt ion or a combination of two or more salt ions, including but not limited to Cr(NO3)3, MnCl2, VCl2.
[0018] The present application also provides a preparation method of a metal-CO2 battery based on a Cu-based nanometer amorphous alloy catalyst, comprising the following steps:
[0019] Step 1, preparation of CO2 electrode: 10 mg Cu-based nanometer amorphous alloy catalyst and 10 mg KB were dispersed in a mixed solution of 1.9 mL ethanol and 0.1 mL Nafion (5.0 wt%), and a uniform slurry was obtained after ultrasonic dispersion for 40 min; the prepared uniform slurry was dropped on a hydrophobic carbon paper with an area of 1 cm 2 , and the catalyst loading was controlled at about 1 mg cm -2 , and the cathode was vacuum dried at a temperature of 80°C for 12 h to obtain a prepared gas diffusion electrode;
[0020] Step 2, assembly of metal-CO2 battery: performed in a glovebox filled with high purity Ar (O2 < 0.01 ppm, H2O < 0.01 ppm), battery with a CR2032 positive shell with holes, the prepared gas diffusion electrode is the positive electrode, the negative electrode is a metal foil with a diameter of 15.6 mm (the metal includes but is not limited to lithium (Li) and sodium (Na)), the separator is glass fiber (diameter 19 mm), and the electrolyte is 1 M LiTFSI / DMSO, the dropwise amount is 200 μL.
[0021] Compared with the prior art, the present application has the following technical effects:
[0022] 1. The composition, phase structure, electronic structure and geometric structure of the Cu-based nanocrystalline alloy catalyst are regulated. By controlling the types and amounts of alloying elements, the composition, phase structure, electronic structure and geometric structure of the Cu-based nanocrystalline alloy catalyst can be accurately regulated, and then the controllable electrocatalytic performance can be obtained.
[0023] 2. The performance of the metal-CO2 battery prepared by the method of the present application is greatly improved. Compared with pure Cu nanocrystalline catalyst and Cu-based nanocrystalline alloy catalyst, the method of the present application can effectively improve the discharge voltage of the metal-CO2 battery, reduce the charging voltage, improve the charge-discharge energy efficiency, increase the cycle life of the battery, etc. BRIEF DESCRIPTION OF DRAWINGS
[0024] Figure 1 is the XRD diffraction pattern of the pure Cu nanocrystalline catalyst in the implementation of the present application;
[0025] Figure 2 is the XRD diffraction pattern of the CuCr-2 nanocrystalline alloy catalyst in the implementation of the present application;
[0026] Figure 3 is the XRD diffraction pattern of the CuCr-3 nanocrystalline alloy catalyst in the implementation of the present application;
[0027] Figure 4 is the cycle performance diagram of the Li-CO2 battery based on the pure Cu nanocrystalline catalyst in the embodiment of the present application at a current density of 50 µA / cm 2 ;
[0028] Figure 5 is the cycle performance diagram of the Li-CO2 battery based on the CuCr-2 nanocrystalline alloy catalyst in the embodiment of the present application at a current density of 50 µA / cm 2 . DETAILED DESCRIPTION
[0029] In order to make the purpose, technical scheme and advantages of the present application more clear, the technical scheme of the application is further described in detail below in combination with the drawings. The described embodiments are only a part of the embodiments involved in the present application. All non-innovative embodiments of other researchers in the field on the basis of the embodiments belong to the protection scope of the present application. Meanwhile, the step numbers in the embodiments are only set for the convenience of description and explanation, and the order between the steps is not limited in any way. The execution order of each step in the embodiments can be adaptively adjusted according to the understanding of those skilled in the art.
[0030] Embodiment one:
[0031] (1) Preparation of pure Cu nanocrystalline catalyst
[0032] Step 1, preparation of carbon carrier suspension liquid: 40 mg of carbon black was dissolved in 40 mL of ethylene glycol, stirred for 10 min, ultrasonically treated for 30 min, and then stirred for 20 min to obtain a uniformly mixed suspension liquid .
[0033] Step 2, preparation of metal precursor solution: 1.2 mmol of CuCl2 was dissolved in 10 mL of ethylene glycol, ultrasonically treated for 30 min, and then stirred for 20 min to obtain a uniformly mixed solution . Then the solution was added dropwise to the suspension liquid to obtain a mixed solution .
[0034] Step 3, preparation of tannic acid solution: 100 mg of tannic acid was added to 10 mL of ethylene glycol, stirred for 10 min, ultrasonically treated for 30 min, and then stirred for 20 min to obtain a uniformly mixed solution . Then the solution was added dropwise to the solution under stirring to obtain a solution .
[0035] Step 4, preparation of NaOH solution: 0.4 g of NaOH was added to 10 mL of deionized water to obtain a solution . The solution was added to the solution and reacted for 10 min. Then, after washing, centrifugation and drying, a pure Cu nanocrystalline catalyst was obtained, which was denoted as 1# catalyst.
[0036] (2) Preparation of metal-CO2 battery
[0037] Step 1, CO2 electrode preparation: 10 mg of pure Cu nanocrystalline catalyst and 10 mg of KB were dispersed in a mixed solution of 1.9 mL of ethanol and 0.1 mL of Nafion (5.0 wt%) to obtain a uniform slurry after ultrasonic dispersion for 40 min. Then the prepared uniform slurry was dropped on a hydrophobic carbon paper with an area of 1 cm 2 , and the loading of the catalyst was controlled at about 1 mg cm -2 . The cathode was vacuum dried at a temperature of 80°C for 12 h to obtain the prepared gas diffusion electrode.
[0038] Step 2, Li-CO2 battery assembly: The battery assembly was carried out in a glove box filled with high-purity Ar (O2 < 0.01 ppm, H2O < 0.01 ppm). The battery used a CR2032 positive shell with a hole, the prepared gas diffusion electrode was the positive electrode, the negative electrode was a metal lithium (Li) with a diameter of 15.6 mm, the separator was a glass fiber (diameter 19 mm), and the electrolyte was 1 M LiTFSI / DMSO with a drop amount of 200 μL. The assembled battery was recorded as 1# battery and placed in a sealed test bottle to replace CO2 gas for 20 min for testing.
[0039] Example Two:
[0040] (1) Preparation of Cu-based nanocrystalline alloy catalyst
[0041] The difference from the preparation process of 1# catalyst is that in step 2, 1.176 mmol of CuCl2 and 0.024 mmol of Cr(NO3)3 were dissolved in 10 mL of ethylene glycol, and a uniformly mixed solution was obtained after ultrasonic dispersion for 30 min and stirring for 20 min . Finally, the CuCr-1 nanocrystalline alloy catalyst was obtained through step 4, which was recorded as 2# catalyst.
[0042] (2) Preparation of metal-CO2 battery
[0043] The difference from the preparation process of 1# battery is that in step 1, 10 mg of CuCr-1 nanocrystalline alloy catalyst and 10 mg of KB were dispersed in a mixed solution of 1.9 mL of ethanol and 0.1 mL of Nafion (5.0 wt%) to obtain a uniform slurry after ultrasonic dispersion for 40 min. Finally, the battery assembled through step 2 was recorded as 2# battery.
[0044] Example Three:
[0045] (1) Preparation of Cu-based nanocrystalline alloy catalyst
[0046] The difference between the preparation process of the 1# catalyst and the preparation process of the 2# catalyst is that, in the preparation of the metal precursor solution in step 2, 1.14 mmol of CuCl2 and 0.06 mmol of Cr(NO3)3 are respectively dissolved in 10 mL of ethylene glycol, and a uniformly mixed solution is obtained after ultrasonic treatment for 30 min and stirring for 20 min Finally, the CuCr-2 nanocrystalline amorphous alloy catalyst is obtained through step 4, which is recorded as the 3# catalyst.
[0047] (2) Preparation of metal-CO2 battery
[0048] The difference between the preparation process of the 1# battery and the preparation process of the 3# battery is that, in the preparation of the CO2 electrode in step 1, 10 mg of CuCr-2 nanocrystalline amorphous alloy catalyst and 10 mg of KB are dispersed in a mixed solution of 1.9 mL of ethanol and 0.1 mL of Nafion (5.0 wt%), and a uniform slurry is obtained after ultrasonic dispersion for 40 min, and finally the battery assembled through step 2 is recorded as the 3# battery.
[0049] Example Four:
[0050] (1) Preparation of Cu-based nanocrystalline amorphous alloy catalyst
[0051] The difference between the preparation process of the 1# catalyst and the preparation process of the 4# catalyst is that, in the preparation of the metal precursor solution in step 2, 0.6 mmol of CuCl2 and 0.6 mmol of Cr(NO3)3 are respectively dissolved in 10 mL of ethylene glycol, and a uniformly mixed solution is obtained after ultrasonic treatment for 30 min and stirring for 20 min Finally, the CuCr-3 nanocrystalline amorphous alloy catalyst is obtained through step 4, which is recorded as the 4# catalyst.
[0052] (2) Preparation of metal-CO2 battery
[0053] The difference between the preparation process of the 1# battery and the preparation process of the 4# battery is that, in the preparation of the CO2 electrode in step 1, 10 mg of CuCr-3 nanocrystalline amorphous alloy catalyst and 10 mg of KB are dispersed in a mixed solution of 1.9 mL of ethanol and 0.1 mL of Nafion (5.0 wt%), and a uniform slurry is obtained after ultrasonic dispersion for 40 min, and finally the battery assembled through step 2 is recorded as the 4# battery.
[0054] Example Five:
[0055] (1) Preparation of Cu-based nanocrystalline amorphous alloy catalyst
[0056] The difference between the preparation process of the 1# catalyst and the preparation process of the 4# catalyst is that, in the preparation of the metal precursor solution in step 2, 0.6 mmol of CuCl2 and 0.6 mmol of Cr(NO3)3 are respectively dissolved in 10 mL of ethylene glycol, and a uniformly mixed solution is obtained after ultrasonic treatment for 30 min and stirring for 20 min .
[0057] And step 3 tannic acid solution preparation, take 500 tannic acid into 10 mL ethylene glycol, stirring 10 min, ultrasonic 30 min, stirring 20 min to obtain a homogeneous solution . Finally, CuCr-4 nanometer amorphous alloy catalyst is obtained through step 4, which is recorded as 5# catalyst.
[0058] (2) Preparation of metal-CO2 battery
[0059] The difference from the preparation process of 1# battery is that: in step 1, 10 mg CuCr-4 nanometer amorphous alloy catalyst and 10 mg KB are dispersed in a mixed solution of 1.9 mL ethanol and 0.1 mL Nafion (5.0wt%), ultrasonic dispersion is performed for 40 min to obtain a uniform slurry, and finally the battery assembled through step 2 is recorded as 5# battery.
[0060] Example six:
[0061] (1) Preparation of Cu-based nanometer amorphous alloy catalyst
[0062] The difference from the preparation process of 5# catalyst is that: in step 2, 0.6 mmol CuCl2 and 0.6 mmol MnCl2 are dissolved into 10 mL ethylene glycol, ultrasonic dispersion is performed for 30 min, and stirring is performed for 20 min to obtain a homogeneous solution .
[0063] And step 3 tannic acid solution preparation, take 100 tannic acid into 10 mL ethylene glycol, stirring 10 min, ultrasonic 30 min, stirring 20 min to obtain a homogeneous solution . Finally, CuMn nanometer amorphous alloy catalyst is obtained through step 4, which is recorded as 6# catalyst.
[0064] (2) Preparation of metal-CO2 battery
[0065] The difference from the preparation process of 5# battery is that: in step 1, 10 mg CuMn nanometer amorphous alloy catalyst and 10 mg KB are dispersed in a mixed solution of 1.9 mL ethanol and 0.1 mL Nafion (5.0wt%), ultrasonic dispersion is performed for 40 min to obtain a uniform slurry, and finally the battery assembled through step 2 is recorded as 6# battery.
[0066] Example seven:
[0067] (1) Preparation of Cu-based nanometer amorphous alloy catalyst
[0068] The difference between the preparation process of the 6# catalyst and the preparation process of the 7# catalyst is that, in the preparation of the metal precursor solution in step 2, 0.6 mmol of CuCl2 and 0.6 mmol of VCl2 are respectively dissolved in 10 mL of ethylene glycol, and a uniformly mixed solution is obtained after ultrasonic treatment for 30 min and stirring for 20 min . Finally, the CuV nanocrystalline alloy catalyst is obtained through step 4, and is denoted as 7# catalyst.
[0069] (2) Preparation of a metal-CO2 battery
[0070] The difference between the preparation process of the 6# battery and the preparation process of the 7# battery is that, in the preparation of the CO2 electrode in step 1, 10 mg of the CuV nanocrystalline alloy catalyst and 10 mg of KB are dispersed in a mixed solution of 1.9 mL of ethanol and 0.1 mL of Nafion (5.0 wt%), and a uniform slurry is obtained after ultrasonic dispersion for 40 min. Finally, the battery assembled through step 2 is denoted as 7# battery.
[0071] Figure 1 The XRD diffraction pattern of the pure Cu nanocrystalline catalyst in Example 1 is shown in the figure, and the results show that the crystal structure presents an amorphous phase. Figure 2 The XRD diffraction pattern of the CuCr-2 nanocrystalline alloy catalyst in Example 3 of the application is shown in the figure, and the results show that the crystal structure presents an amorphous phase. Figure 3 The XRD diffraction pattern of the CuCr-3 nanocrystalline alloy catalyst in Example 4 of the application is shown in the figure, and the results show that the crystal structure presents an amorphous phase. The above results show that the application provides a general technical means for preparing a Cu-based nanocrystalline alloy catalyst.
[0072] As shown in Figure 4 , the cycle performance of a Li-CO2 battery based on a pure Cu nanocrystalline catalyst at a current density of 50 µA / cm 2 is shown in the figure. As shown in Figure 5 , the cycle performance of a Li-CO2 battery based on a CuCr-2 nanocrystalline alloy catalyst at a current density of 50 µA / cm 2 is shown in the figure. By comparing the results of Figure 4 and Figure 5 , it can be seen that the CuCr-2 nanocrystalline alloy catalyst can effectively improve the reaction kinetics during the discharge and charge processes of the Li-CO2 battery. Compared with the pure Cu nanocrystalline catalyst, the Li-CO2 battery based on the CuCr-2 nanocrystalline alloy catalyst exhibits low charge-discharge polarization overpotential, high energy efficiency and more durable charge-discharge cycle stability, indicating that the Cu-based nanocrystalline alloy is a highly efficient positive electrode catalyst for a Li-CO2 battery.
[0073] The above merely describes the preferred embodiments of the present application, and it should be pointed out that those skilled in the art can make several improvements and refinements without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.
Claims
1. A Cu-based nanocrystalline amorphous alloy catalyst, characterized in that, The Cu-based nano-amorphous alloy catalyst is composed of binary or ternary or higher nano-alloys formed by the main element Cu and one or more alloying elements Cr, Mn, and V, and its phase structure is a long-range disordered amorphous crystal structure. The morphology of the Cu-based nano-amorphous alloy catalyst is irregular spherical nanoparticles.
2. The Cu-based nanocrystalline amorphous alloy catalyst according to claim 1, characterized in that, The irregular spherical nanoparticles have a size of 2 to 40 nanometers.
3. A metal-CO2 battery based on the Cu-based nanocrystalline amorphous alloy catalyst of claim 1 or 2, characterized in that, Cu-based nano-amorphous alloy catalysts are used to catalyze the CO2 reduction and Li2CO3 decomposition reactions on the positive electrode side of metal-CO2 batteries. CO2 reduction corresponds to the discharge process of the metal-CO2 battery, and Li2CO3 decomposition corresponds to the charging process of the metal-CO2 battery. The discharge voltage of the metal-CO2 battery based on the Cu-based nano-amorphous alloy catalyst is higher than that of the metal-CO2 battery based on the pure Cu nano-amorphous catalyst, while the charging voltage of the metal-CO2 battery based on the Cu-based nano-amorphous alloy catalyst is lower than that of the metal-CO2 battery based on the pure Cu nano-amorphous catalyst.
4. A method for preparing the Cu-based nanocrystalline amorphous alloy catalyst according to claim 1 or 2, characterized in that, Includes the following steps: Step 1: Preparation of carbon support suspension: Dissolve 40 mg of carbon black in 40 mL of ethylene glycol, stir for 10 min, sonicate for 30 min, and then stir for another 20 min to obtain a homogeneous suspension. ; Step 2: Preparation of the metal precursor solution: Dissolve 0.6–1.2 mmol of CuCl2 and 0.6–0 mmol of the alloyed metal salt in 10 mL of ethylene glycol, sonicate for 30 min, and stir for 20 min to obtain a homogeneous solution. , the solution Added dropwise to suspension In the process, a mixed solution is obtained. ; Step 3: Preparation of tannic acid solution: Add 100-500 mg of tannic acid to 10 mL of ethylene glycol, stir for 10 min, sonicate for 30 min, and stir for 20 min to obtain a homogeneous solution. The solution is stirred. Add dropwise to the mixed solution In, obtain solution ; Step 4: Preparation of NaOH solution: Add 0.4 g of NaOH to 10 mL of deionized water to obtain the solution. ; the solution Add solution The reaction was carried out for 10 min, and then Cu-based nano-amorphous alloy catalyst was obtained by washing, centrifugation and drying.
5. The method for preparing the Cu-based nanocrystalline amorphous alloy catalyst according to claim 4, characterized in that, The alloyed metal salt is a single salt ion or a combination of two or more salt ions, including but not limited to Cr(NO3)3, MnCl2, and VCl2.
6. A method for preparing the metal-CO2 battery according to claim 3, characterized in that, Includes the following steps: Step 1, Preparation of CO2 Electrode: 10 mg of Cu-based nano-amorphous alloy catalyst and 10 mg of KB were dispersed in a mixed solution of 1.9 mL ethanol and 0.1 mL Nafion, and ultrasonically dispersed for 40 min to obtain a uniform slurry; the prepared uniform slurry was dropped onto a surface with an area of 1 cm². 2 On hydrophobic carbon paper, the catalyst loading was controlled at 1 mg / cm³. -2 The cathode was vacuum dried at 80°C for 12 h to obtain the prepared gas diffusion electrode. Step 2, Assembly of the metal-CO2 battery: The assembly was carried out in a glove box filled with high-purity Ar. The battery used a perforated CR2032 positive electrode shell, the prepared gas diffusion electrode was the positive electrode, the negative electrode was a metal foil with a diameter of 15.6 mm, the separator was made of glass fiber, and the electrolyte was 1 M LiTFSI / DMSO, with a drop volume of 200 μL.