Method for preparing porous catalyst gas diffusion electrode by magnetron sputtering and electrode

Abstract

This invention provides a method for preparing a porous catalyst gas diffusion electrode by magnetron sputtering and the electrode itself, belonging to the field of water electrolysis technology. The method includes: providing an anode diffusion layer as a substrate; using a first element and a second element as dual targets, wherein the first element belongs to at least one element in Group VIII and the second element belongs to at least one transition element; evacuating the magnetron sputtering environment to a first pressure, introducing argon gas, and then adjusting the pressure to a second pressure; alternately sputtering the first element as the first target and the second element as the second target on the anode diffusion layer to form a heterojunction or alloy layer; performing pore-forming treatment on the heterojunction or alloy layer, cleaning, calcining, and cooling to obtain the porous catalyst gas diffusion electrode. This invention uses magnetron sputtering to prepare a porous catalyst gas diffusion electrode, preventing the catalyst from easily detaching from the proton exchange membrane, thus improving the catalyst activity and consequently the activity of the membrane electrode.

Description

Technical Field

[0001] This invention belongs to the field of water electrolysis technology, and particularly relates to a method for preparing a porous catalyst gas diffusion electrode by magnetron sputtering and the electrode itself. Background Technology

[0002] In hydrogen production via water electrolysis, the electrolytic reactor is the site of the electrochemical reaction. In the reactor, water at the anode is catalytically oxidized on the catalyst surface to produce oxygen, which is then discharged by the water flow. Protons pass through the proton exchange membrane to the cathode catalyst, where they gain electrons under the catalyst's catalytic action to generate hydrogen. Under otherwise identical conditions (e.g., bipolar plates, diffusion layer, proton exchange membrane, etc.), the DC efficiency and lifespan of the electrolytic reactor are primarily limited by the activity and stability of the anode catalyst.

[0003] In existing electrolyzers, the cathode catalyst and anode catalyst are typically coated on opposite sides of a proton exchange membrane, and then combined with the cathode diffusion layer and anode diffusion layer to form a "five-in-one" membrane electrode assembly (MEA). During the water electrolysis reaction, water is oxidized to oxygen on the anode catalyst layer, while protons are transferred through the proton exchange membrane to the cathode catalyst layer under the influence of an electric field, where they are further reduced to hydrogen. Oxygen and hydrogen are then discharged from the electrolyzer through the gas diffusion layer into the flow channels, completing the process of producing hydrogen and oxygen through electrolysis.

[0004] Existing membrane electrode assemblies (MEAs) involve directly coating the anode and cathode catalyst layers onto both sides of a proton exchange membrane. To ensure MEA activity, a high catalyst loading is often required on the anode side. During the electrolysis of water to generate bubbles, the catalyst layer is easily disturbed by the gas and detaches. Furthermore, under high voltage, the microstructure of the anode catalyst changes, resulting in loss of catalytic function and reduced MEA activity. Moreover, with prolonged reaction time, the proton exchange membrane gradually degrades from the outside in, and the catalyst also detaches from the membrane, losing its catalytic effect and making the MEA relatively prone to deactivation. Summary of the Invention

[0005] This invention provides a method for preparing a porous catalyst gas diffusion electrode by magnetron sputtering and the electrode itself. This method addresses the problems of catalyst layer detachment due to gas disturbance during water electrolysis to generate bubbles; even under high voltage, the microstructure of the anode catalyst changes, leading to loss of catalytic function and reduced membrane electrode activity. Furthermore, with prolonged reaction time, the proton exchange membrane gradually degrades from the outside in, and the catalyst detaches from the membrane, losing its catalytic effect and causing the membrane electrode to easily deactivate.

[0006] The technical solution provided by this invention is as follows:

[0007] On one hand, embodiments of the present invention provide a magnetron sputtering preparation method, the method comprising:

[0008] An anodic diffusion layer is provided as a substrate, and a first element and a second element are used as dual targets, wherein the first element belongs to at least one of the group VIII elements and the second element belongs to at least one of the transition elements;

[0009] The magnetron sputtering environment pressure is evacuated to the first pressure, and argon gas is introduced and then the pressure is adjusted to the second pressure.

[0010] Using the first element as the first target and the second element as the second target, sputtering is performed alternately on the anode diffusion layer to form a heterojunction or alloy layer;

[0011] The heterojunction or alloy layer is subjected to pore-forming treatment, cleaned, calcined, and cooled to obtain the porous catalyst gas diffusion electrode.

[0012] In one alternative embodiment, the first element is iridium, and the second element includes at least one or more of silicon, aluminum, manganese, iron, nickel, and cobalt.

[0013] In one optional embodiment, the molar ratio of the first element to the second element is 1:10 to 15.

[0014] In one optional embodiment, the deposition rate of the first element is 0.015 nm / s to 0.035 nm / s, and the deposition rate of the second element is 0.025 nm / s to 0.035 nm / s.

[0015] In one optional embodiment, the sputtering time of the first element is 20s to 30s, and the sputtering time of the second element is 80s to 100s.

[0016] The number of alternating sputtering operations is 20 to 30 times.

[0017] In one optional embodiment, the heterojunction or alloy layer that has undergone pore-forming treatment is cleaned with deionized water and calcined at a preset temperature for 5 to 8 hours. After cooling, the porous catalyst gas diffusion electrode is obtained.

[0018] In one optional embodiment, the pore-forming treatment of the heterojunction or alloy layer includes pore-forming treatment with a 3 mol / L to 5 mol / L acid solution or a 3 mol / L to 5 mol / L alkaline solution.

[0019] In one optional embodiment, the acid solution includes at least one of nitric acid, sulfuric acid, or hydrochloric acid, and the alkaline solution is sodium hydroxide.

[0020] In another aspect, a porous catalyst gas diffusion electrode is provided, characterized in that the electrode is prepared using any of the methods described above, wherein the electrode comprises:

[0021] An anode diffusion layer serves as the substrate for the electrode;

[0022] A porous structure formed by a heterojunction or alloy is located on the anode diffusion layer.

[0023] In one alternative embodiment, the porous structure formed by the heterojunction or alloy includes a porous structure formed by an alloy of the first element and the second element.

[0024] In one alternative embodiment, in the porous structure formed by the alloy of the first element and the second element, the thickness of the first element is greater than the thickness of the second element.

[0025] In an alternative embodiment, the first element is iridium.

[0026] In one alternative embodiment, the second element includes at least one or more of silicon, aluminum, manganese, iron, nickel, and cobalt.

[0027] In one optional embodiment, the molar ratio of the first element to the second element is 1:10 to 15. Attached Figure Description

[0028] The above and other objects, features and advantages of this disclosure will become more apparent from the accompanying drawings, in which like reference numerals generally denote like parts.

[0029] Figure 1 A schematic diagram of a process for preparing a porous catalyst gas diffusion electrode by magnetron sputtering is shown.

[0030] Figure 2 A schematic diagram of a porous catalyst gas diffusion electrode structure is shown.

[0031] The attached figures are labeled as follows:

[0032] 1-Anode diffusion layer, 2-Heterojunction or alloy layer, 3-Porous catalyst gas diffusion electrode, 100-Porous structure. Detailed Implementation

[0033] Embodiments of the present disclosure will now be described in more detail with reference to the accompanying drawings. While embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be implemented in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0034] The term "comprising" and its variations as used herein signify open inclusion, i.e., "including but not limited to". Unless otherwise stated, the term "based on" means "at least partially based on". The terms "an example embodiment" and "an embodiment" mean "at least one example embodiment". The term "another embodiment" means "at least one additional embodiment". The terms "first", "second", etc., may refer to different or the same objects. Other explicit and implicit definitions may also be included below.

[0035] On the one hand, a method for preparing porous catalyst gas diffusion electrodes by magnetron sputtering is provided; please refer to [link to relevant documentation]. Figure 1 The methods include:

[0036] S1. Provide an anode diffusion layer 1 as a substrate, and use a first element and a second element as dual targets, wherein the first element belongs to at least one of the group VIII elements, and the second element belongs to at least one of the transition elements.

[0037] S2. Evacuate the magnetron sputtering environment to the first pressure, introduce argon gas, and then adjust the pressure to the second pressure.

[0038] S3. Sputtering is performed alternately on the anode diffusion layer 1 using the first element as the first target and the second element as the second target to form a heterojunction or alloy layer 2.

[0039] S4. Pore-forming treatment is performed on the heterojunction or alloy layer 2, followed by cleaning and calcination. After cooling, a porous catalyst gas diffusion electrode 3 is obtained.

[0040] The method provided in this embodiment of the invention has at least the following beneficial effects:

[0041] The method provided in this invention uses a first element and a second element as dual targets. By sputtering the dual targets onto the anode diffusion layer 1 using magnetron sputtering, a heterojunction or alloy layer 2 can be rapidly prepared. Furthermore, by alternately sputtering the first and second targets onto the anode diffusion layer 1, multiple heterojunctions or alloy layers 2 are formed, increasing the exposure area of ​​the first target and significantly improving its activity and utilization rate. Finally, pore-forming treatment is performed on the heterojunction or alloy layer 2 to obtain a porous catalyst gas diffusion electrode 3. Based on this invention, the porous catalyst gas diffusion electrode 3 prepared by magnetron sputtering does not easily detach from the proton exchange membrane, improving the catalyst activity and thus enhancing the activity of the membrane electrode.

[0042] The following optional embodiments will further explain and illustrate the present invention, which provides a method for preparing a porous catalyst gas diffusion electrode 3 by magnetron sputtering and the electrode.

[0043] S1. Provide an anode diffusion layer 1 as a substrate, and use a first element and a second element as dual targets, wherein the first element belongs to at least one of the group VIII elements, and the second element belongs to at least one of the transition elements.

[0044] In one alternative embodiment, the first element is iridium, and the second element includes at least one or more of silicon, aluminum, manganese, iron, nickel, and cobalt.

[0045] Furthermore, the second element can be silicon, aluminum, manganese, iron, nickel, or cobalt, or it can be a silicon-aluminum alloy, an alloy of silicon, aluminum, and manganese, an alloy of silicon, aluminum, manganese, iron, and nickel, or an alloy of silicon, aluminum, manganese, iron, nickel, and cobalt. The embodiments of the present invention are not limited to selecting these element alloys as the second element.

[0046] S2. Evacuate the magnetron sputtering environment to the first pressure, introduce argon gas, and then adjust the pressure to the second pressure.

[0047] Before sputtering, the magnetron sputtering environment pressure is first evacuated to 0.0004 Pa to 0.0005 Pa, i.e., the first pressure. Examples include 0.0004 Pa, 0.0042 Pa, 0.0045 Pa, 0.0047 Pa, 0.0049 Pa, and 0.0005 Pa. After introducing argon gas, the pressure is adjusted to the second pressure, i.e., 1 Pa to 3 Pa. Examples include 1 Pa, 1 Pa, 1.3 Pa, 1.5 Pa, 1.6 Pa, 1.8 Pa, 1.9 Pa, 2.1 Pa, 2.4 Pa, 2.5 Pa, 2.6 Pa, 2.7 Pa, and 3 Pa.

[0048] In one alternative embodiment, the molar ratio of the first element to the second element is 1:10 to 15.

[0049] It should be noted that the size of the pores in the porous catalyst gas diffusion electrode 3 provided in this embodiment of the invention is determined by the content of the first element and the second element. In this embodiment, the molar ratio of the first element to the second element includes 1:10 to 15. For example, it can be 1:10, 1:11, 1:12, 1:13, 1:14 or 1:15, etc.

[0050] S3. Sputtering is performed alternately on the anode diffusion layer 1 using the first element as the first target and the second element as the second target to form a heterojunction or alloy layer 2.

[0051] In this embodiment of the invention, a first element is used as the first target material. Specifically, iridium is first sputtered onto the anode diffusion layer 1, and then a second target material, i.e., the second element, is sputtered onto the iridium layer. This sputtering of iridium and the second element is repeated until the desired thickness is achieved, at which point sputtering stops, forming a heterojunction or alloy layer 2. By first sputtering iridium and then alternately sputtering the second element to form a multilayer heterojunction or alloy layer 2, the interlayer bonding force between the heterojunctions or alloy layers 2 can be improved, preventing detachment even under high temperature and high pressure, thereby enhancing the activity of the membrane electrode.

[0052] In one optional embodiment, the deposition rate of the first element is 0.015 nm / s to 0.035 nm / s, and the deposition rate of the second element is 0.025 nm / s to 0.035 nm / s.

[0053] It should be noted that the deposition rate of the first element and the second element determines the size of the pores in the porous catalyst gas diffusion electrode 3. That is, the faster the deposition rate, the greater the thickness of the deposited first element and the second element.

[0054] As an example, the deposition rate of the first element can be 0.015 nm / s, 0.016, 0.017, 0.019, 0.020, 0.022, 0.023, 0.025, 0.026 nm / s, 0.027 nm / s, 0.028 nm / s, 0.029 nm / s, 0.03 nm / s, 0.31 nm / s, 0.32 nm / s, 0.33 nm / s, 0.34 nm / s, or 0.35 nm / s, etc. The second metal deposition rate can be 0.025 nm / s, 0.026 nm / s, 0.027 nm / s, 0.028 nm / s, 0.029 nm / s, 0.03 nm / s, 0.31 nm / s, 0.32 nm / s, 0.33 nm / s, 0.34 nm / s, or 0.35 nm / s, etc.

[0055] In one optional embodiment, the sputtering time of the first element is 20s to 30s, and the sputtering time of the second element is 80s to 100s.

[0056] The number of alternating splashes is 20 to 30.

[0057] The sputtering time for the first element can be 20s, 21s, 22s, 23s, 25s, 27s, 28s, 29s, or 30s. The sputtering time for the second element can be 80s, 81s, 82s, 83s, 85s, 87s, 88s, 89s, 92s, 94s, 95s, 96s, 97s, 98s, 99s, or 100s.

[0058] The number of alternating splashes is 20, 23, 24, 25, 27, 28, 28, and 30.

[0059] S4. Pore-forming treatment is performed on the heterojunction or alloy layer 2, followed by cleaning and calcination. After cooling, a porous catalyst gas diffusion electrode 3 is obtained.

[0060] In one optional embodiment, the heterojunction or alloy layer 2 that has undergone pore-forming treatment is cleaned with deionized water and calcined at a preset temperature for 5 to 8 hours. After cooling, a porous catalyst gas diffusion electrode 3 is obtained.

[0061] The heterojunction or alloy layer 2, after acid or alkali washing to create pores, is cleaned with deionized water to remove the acid or alkali solution, and then calcined at a high temperature of 200℃ to 300℃. For example, calcination temperatures of 200℃, 210℃, 240℃, 260℃, 270℃, 290℃, and 300℃ can be used. The calcination time can be 5 hours, 6 hours, 7 hours, or 8 hours.

[0062] In one optional embodiment, the heterojunction or alloy layer 2 is subjected to a pore-forming process, including pore-forming through a 3 mol / L to 5 mol / L acid solution or a 3 mol / L to 5 mol / L alkaline solution.

[0063] For example, the concentration of the acid solution can be 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, or 5 mol / L. The concentration of the alkaline solution can be 3 mol / L, 3.5 mol / L, 4 mol / L, 4.5 mol / L, or 5 mol / L.

[0064] In one optional embodiment, the acid solution includes at least one of nitric acid, sulfuric acid, or hydrochloric acid. In one optional embodiment, the alkaline solution may be sodium hydroxide.

[0065] It should be noted that, in this embodiment of the invention, a porous structure 100 is formed by corroding the heterojunction or alloy layer 2 through acid or alkali washing, specifically by etching the second element (silicon, aluminum, manganese, iron, nickel, or cobalt) and the second element bonded to the first element. The acid solution can be one or a mixture of several of nitric acid, sulfuric acid, or hydrochloric acid. This embodiment of the invention does not limit the type of acid solution mixture.

[0066] On the other hand, please see Figure 2 A porous catalyst gas diffusion electrode 3 is also provided, the electrode being prepared using any of the methods described above, wherein the electrode comprises:

[0067] Anode diffusion layer 1 serves as the substrate for the electrode;

[0068] A porous structure 100 formed by a heterojunction or alloy is located on the anode diffusion layer 1.

[0069] In one alternative embodiment, the porous structure 100 formed by the heterojunction or alloy includes a porous structure formed by a first element and a second element forming an alloy or heterojunction.

[0070] In this embodiment of the invention, a porous structure 100 is formed by corroding a second element, namely silicon, aluminum, manganese, iron, nickel or cobalt, through acid washing or alkali washing, on the heterojunction or alloy layer 2. The second element, which is combined with the first element, is corroded.

[0071] In one alternative embodiment, in the porous alloy or heterojunction formed by the first element and the second element, the thickness of the first element is less than the thickness of the second element.

[0072] By setting the thickness of the first element to be less than the thickness of the second element, a porous structure can be formed in the second element after it is corroded by an acid or alkali solution. For example, the thickness of the first element can be 5-10 times the thickness of the second element. Examples include 5, 6, 7, 8, 9, and 10 times the thickness.

[0073] In one alternative embodiment, the first element is iridium.

[0074] In one alternative embodiment, the second element includes at least one or more of silicon, aluminum, manganese, iron, nickel, and cobalt.

[0075] Furthermore, the second element can be silicon, aluminum, manganese, iron, nickel, or cobalt, or it can be a silicon-aluminum alloy, an alloy of silicon, aluminum, and manganese, an alloy of silicon, aluminum, manganese, iron, and nickel, or an alloy of silicon, aluminum, manganese, iron, nickel, and cobalt. The embodiments of the present invention are not limited to selecting these element alloys as the second element.

[0076] In one alternative embodiment, the molar ratio of the first element to the second element is 1:10 to 15.

[0077] It should be noted that the size of the pores in the porous catalyst gas diffusion electrode 3 provided in this embodiment of the invention is determined by the content of the first element and the second element. In this embodiment, the molar ratio of the first element to the second element includes 1:10 to 15. For example, it can be 1:10, 1:11, 1:12, 1:13, 1:14 or 1:15, etc.

[0078] The methods and electrodes provided in the embodiments of the present invention will be further described below through specific examples.

[0079] Example 1

[0080] The specific process is as follows: Figure 2 As shown. Anode diffusion layer 1 was used as the substrate, and iridium and cobalt were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0004 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using cobalt as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0081] Remove the magnetron sputtered anode diffusion layer 1, transfer it to a 3M nitric acid (HNO3) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine it at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0082] Example 2

[0083] Using anodic diffusion layer 1 as the substrate, iridium and nickel were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0004 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using nickel as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0084] Remove the magnetron sputtered anode diffusion layer 1, transfer it to a 3M nitric acid (HNO3) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine it at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0085] Example 3

[0086] Using anodic diffusion layer 1 as the substrate, iridium and iron were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0005 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using iron as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0087] Remove the diffusion layer deposited by magnetron sputtering, transfer it to a 3M nitric acid (HNO3) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine it at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0088] Example 4

[0089] Using anodic diffusion layer 1 as the substrate, iridium and manganese were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0005 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using manganese as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0090] Remove the diffusion layer deposited by magnetron sputtering, transfer it to a 3M nitric acid (HNO3) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine it at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0091] Example 5

[0092] Using anodic diffusion layer 1 as the substrate, iridium and aluminum were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0004–0.0005 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using aluminum as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0093] Remove the diffusion layer deposited by magnetron sputtering, transfer it to a 3M sodium hydroxide (NaOH) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0094] Example 6

[0095] Using anodic diffusion layer 1 as the substrate, iridium and silicon were used as dual targets. Before sputtering, the pressure in the vacuum chamber was evacuated to 0.0005 Pa, and high-purity argon gas was introduced to adjust the vacuum chamber pressure to 1 Pa. Using iridium as the target, magnetron sputtering was performed at a deposition rate of 0.015 nm / s for 20 seconds; using silicon as the target, magnetron sputtering was performed at a deposition rate of 0.025 nm / s for 80 seconds; these two steps were repeated 20 times in sequence.

[0096] Remove the diffusion layer deposited by magnetron sputtering, transfer it to a 3M sodium hydroxide (NaOH) solution, soak for half an hour, remove it and wash with deionized water. Place the anode diffusion layer 1 in a nitrogen or vacuum furnace and calcine at 200°C for five hours, then allow it to cool naturally to obtain a porous catalyst gas diffusion electrode 3 with a porous catalyst layer.

[0097] The various embodiments of this disclosure have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or technical improvements to the embodiments in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A method for preparing a porous catalyst gas diffusion electrode by magnetron sputtering, characterized in that, The method includes: An anodic diffusion layer is provided as a substrate, and a first element and a second element are used as dual targets, wherein the first element belongs to at least one of the group VIII elements and the second element belongs to at least one of the transition elements; The magnetron sputtering environment pressure is evacuated to the first pressure, and argon gas is introduced and then the pressure is adjusted to the second pressure. Using the first element as the first target and the second element as the second target, sputtering is performed alternately on the anode diffusion layer to form a heterojunction or alloy layer; The heterojunction or alloy layer is subjected to pore-forming treatment, cleaned, calcined, and cooled to obtain the porous catalyst gas diffusion electrode. The first element is iridium, and the second element includes at least one or more of silicon, aluminum, manganese, iron, nickel, and cobalt. The deposition rate of the first element is 0.015 nm / s to 0.035 nm / s, and the deposition rate of the second element is 0.025 nm / s to 0.035 nm / s. The sputtering time for the first element is 20s to 30s, and the sputtering time for the second element is 80s to 100s. The number of alternating sputtering operations is 20 to 30 times; The pore-forming process for the heterojunction or alloy layer includes pore-forming through a 3 mol / L to 5 mol / L acid solution or a 3 mol / L to 5 mol / L alkaline solution.

2. The method according to claim 1, characterized in that, The molar ratio of the first element to the second element includes 1:10 to 15.

3. The method according to claim 1, characterized in that, The heterojunction or alloy layer that has undergone pore-forming treatment is cleaned with deionized water and calcined at a preset temperature for 5 to 8 hours. After cooling, the porous catalyst gas diffusion electrode is obtained.

4. The method according to claim 1, characterized in that, The acid solution includes at least one of nitric acid, sulfuric acid, or hydrochloric acid, and the alkaline solution is sodium hydroxide.

5. A porous catalyst gas diffusion electrode, characterized in that, The electrode is prepared using the method according to any one of claims 1-4, wherein the electrode comprises: An anode diffusion layer serves as the substrate for the electrode; A porous structure formed by a heterojunction or alloy is located on the anode diffusion layer.

6. The porous catalyst gas diffusion electrode according to claim 5, characterized in that, The porous structure formed by the heterojunction or alloy includes the porous structure formed by the first element and the second element forming the alloy or heterojunction.

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