A catalyst, its preparation and use
By preparing Fe-Mn-N/C catalysts, the problem of high cost of Pt-based catalysts in fuel cells was solved, realizing the efficient application of non-precious metal catalysts in fuel cells, reducing costs and improving performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- DONGFENG MOTOR GRP
- Filing Date
- 2024-09-23
- Publication Date
- 2026-05-22
AI Technical Summary
The use of Pt-based catalysts in existing proton exchange membrane fuel cells is costly and has low reserves. The performance of non-precious metal catalysts in actual fuel cell tests is still lower than that of Pt-based materials, making it difficult to achieve low-cost commercialization.
Fe-Mn-N/C catalysts were prepared by mixing iron, manganese, and nitrogen-rich organic precursors with silica, followed by drying, heat treatment, and silica removal. These catalysts were then used as cathode catalyst layers in fuel cells to form an effective three-phase boundary.
It improves the catalytic performance of non-precious metal catalysts, reduces costs, and exhibits performance comparable to Pt/C catalysts in actual fuel cell tests.
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Figure CN119361720B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of fuel cell technology, and in particular to a catalyst, its preparation method, and its application. Background Technology
[0002] Proton exchange membrane fuel cells (PEMFCs) are a widely used and promising type of fuel cell. Cost is one of the key issues hindering their widespread adoption. Pt and its alloys are generally used as the main catalyst material in PEMFCs. Pt is a precious metal, making it expensive to use, and its reserves in China are not high. A major focus of current fuel cell development is reducing Pt loading or using non-precious metal catalysts. To achieve long-term and effective low-cost commercialization of fuel cells, the development of non-precious metal catalysts is essential.
[0003] Researchers are dedicated to studying non-precious metal catalysts, including non-precious metal oxides, non-precious metal nitrides and oxides, non-precious metal carbonitrides, non-precious metal chalcogenides, N-doped carbon materials, and MN / C catalysts (where M represents Fe, Co, etc.). Their aim is to revolutionize the fuel cell catalyst industry and develop highly efficient and stable non-precious metal catalysts that can replace Pt-based catalysts. Currently, Fe-N / C catalysts exhibit promising catalytic performance and are considered the most likely candidate to replace Pt-based catalysts.
[0004] Although non-platinum catalysts have improved catalytic activity, their performance in actual fuel cell tests is still lower than that of Pt-based materials. Summary of the Invention
[0005] This application provides a catalyst, its preparation method, and its application to improve the performance of non-platinum catalysts in practical fuel cell testing.
[0006] In a first aspect, this application provides a method for preparing a catalyst, the method comprising:
[0007] Iron source, manganese source, nitrogen-rich organic precursor and silica are dispersed in solvent to obtain a mixed paste;
[0008] The mixed paste is dried to obtain an intermediate powder;
[0009] The intermediate powder is subjected to a first heat treatment, and then the silica in the intermediate powder after the first heat treatment is removed to obtain a crude catalyst.
[0010] The crude catalyst is subjected to a second heat treatment to obtain the catalyst.
[0011] As an optional implementation, the molar ratio of iron to manganese in the iron source and manganese source is (1-2):1.
[0012] As an optional implementation, the temperature of the second heat treatment is 1000℃~1100℃; and / or
[0013] The second heat treatment time is 40 min to 50 min; and / or
[0014] The atmosphere for the second heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere.
[0015] As an optional implementation, the iron source includes iron; and / or
[0016] The manganese source includes manganese nitrate; and / or
[0017] The nitrogen-rich organic precursor includes at least one of nicarbazin and piperidine acid; and / or
[0018] The surface area of the silicon dioxide does not exceed 150m². 2 / g.
[0019] As an optional implementation, the drying temperature is 80°C to 100°C; and / or
[0020] The drying time is 8 to 12 hours.
[0021] As an optional implementation, the temperature of the first heat treatment is 900℃~1000℃; and / or
[0022] The first heat treatment time is 80 min to 100 min; and / or
[0023] The atmosphere for the first heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere.
[0024] As an optional implementation, the silica in the intermediate powder is removed by immersion; and / or
[0025] The soaking solution includes an HF solution; and / or
[0026] The HF solution has a mass concentration of 20% to 30%; and / or
[0027] The soaking time is 20h to 28h.
[0028] Secondly, this application provides a catalyst prepared using the method provided in the first aspect.
[0029] Thirdly, this application provides a membrane electrode, the membrane electrode including a cathode, the cathode including the catalyst provided in the second aspect.
[0030] As an optional implementation, the catalyst loading on the cathode is 2.0 mg / cm³. 2 ~3.0mg / cm 2 .
[0031] The technical solutions provided in this application have the following advantages compared with the prior art:
[0032] The method provided in this application provides that prepares an MN / C catalyst using iron and manganese sources and introduces Mn into the Fe-N / C catalyst. This catalyst has good catalytic performance and can achieve an effective three-phase boundary when applied to the cathode catalyst layer, thereby improving the performance of the catalyst in actual fuel cell tests. Attached Figure Description
[0033] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0034] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0035] Figure 1 A flowchart illustrating the method provided in the embodiments of this application;
[0036] Figure 2 Polarization curves of membrane electrodes formed by catalysts provided in the embodiments and comparative examples of this application. Detailed Implementation
[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0038] Unless otherwise specified, all raw materials, reagents, instruments and equipment used in this application can be purchased from the market or prepared by existing methods.
[0039] Figure 1 A flowchart illustrating the method provided in the embodiments of this application, as shown below. Figure 1 As shown in the embodiments of this application, a method for preparing a catalyst is provided, the method comprising:
[0040] S1. Disperse the iron source, manganese source, nitrogen-rich organic precursor and silica in a solvent to obtain a mixed paste;
[0041] In some embodiments, the molar ratio of iron to manganese in the iron source and manganese source is (1-2):1.
[0042] Doping with Mn can improve the oxygen reduction activity of Fe-doped non-Pt catalysts. The molar ratio of iron to manganese in the iron and manganese sources should be controlled at (1-2):1. If the molar ratio is too large, there will be fewer active sites, reducing catalytic performance; if the molar ratio is too small, the formed catalyst layer structure will be blocked, preventing the formation of mass transfer channels.
[0043] For example, the molar ratio of iron to manganese in the iron source and manganese source can be 1:1, 1.1:1, 1.2:1, 1.3:1, 1.4:1, 1.5:1, 1.6:1, 1.7:1, 1.8:1, 1.9:1 or 2:1, etc., or any value in the range of (1 to 2):1.
[0044] In some embodiments, the iron source comprises iron; the manganese source comprises manganese nitrate; the nitrogen-rich organic precursor comprises at least one of nicarbazine and piperidine acid; and the surface area of silica does not exceed 150 m². 2 / g.
[0045] Specifically, in this embodiment, iron and manganese nitrates (the molar ratio of Fe to Mn can be 1:1 to 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidinic acid), and sufficient fumed silica (surface area ~150m²) are used. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0046] S2. Dry the mixed paste to obtain an intermediate powder;
[0047] In some embodiments, the drying temperature is 80℃ to 100℃; the drying time is 8 to 12 hours. For example, the drying temperature can be 80℃, 85℃, 90℃, 95℃, or 100℃, or any value within the range of 80℃ to 100℃. The drying time can be 8 hours, 8.5 hours, 9 hours, 9.5 hours, 10 hours, 10.5 hours, 11 hours, 11.5 hours, or 12 hours, or any value within the range of 8 to 12 hours.
[0048] S3. The intermediate powder is subjected to a first heat treatment, and then the silicon dioxide in the intermediate powder after the first heat treatment is removed to obtain a crude catalyst.
[0049] In some embodiments, the temperature of the first heat treatment is 900℃ to 1000℃; the time of the first heat treatment is 80 min to 100 min. Exemplarily, the temperature of the first heat treatment can be 900℃, 910℃, 920℃, 930℃, 940℃, 950℃, 960℃, 970℃, 980℃, 990℃, or 1000℃, or any value within the range of 900℃ to 1000℃. The time of the second heat treatment can be 80 min, 82 min, 84 min, 86 min, 88 min, 90 min, 92 min, 94 min, 96 min, 98 min, or 100 min, or any value within the range of 80 min to 100 min.
[0050] In some embodiments, the atmosphere for the first heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere. The inert gas atmosphere may be an argon atmosphere, etc.
[0051] In some embodiments, silica in the intermediate powder is removed by immersion. The immersion solution includes an HF solution; further, the mass concentration of the HF solution is 20%–30%. Exemplarily, the mass concentration of the HF solution can be 20%, 21%, 22%, 23%, 24%, 25%, 26%, 27%, 28%, 29%, or 30%, or any value within the range of 20%–30%. The immersion time is 20 hours–28 hours; exemplaryly, the immersion time can be 20 hours, 21 hours, 22 hours, 23 hours, 24 hours, 25 hours, 26 hours, 27 hours, or 28 hours.
[0052] Specifically, in this embodiment, the dried intermediate powder is heat-treated in a N2 atmosphere at 950°C for 90 min, and then soaked in a 25% HF solution for 24 h to remove silica impurities. After that, it is thoroughly washed with water until pH≈6 to obtain the crude catalyst.
[0053] S4. The crude catalyst is subjected to a second heat treatment to obtain the catalyst.
[0054] In some embodiments, the temperature of the second heat treatment is 1000℃~1100℃; the time of the second heat treatment is 40min~50min.
[0055] After high-temperature heat treatment, the reaction tends to follow a four-electron reaction mechanism, enhancing the activity and stability of such catalysts. The temperature is controlled between 1000℃ and 1100℃. Too low a temperature will lead to incomplete reaction, while too high a temperature will cause the product crystals to become larger and the specific surface area to decrease, both of which will affect the properties of the product.
[0056] For example, the temperature of the second heat treatment can be 1000℃, 1010℃, 1020℃, 1030℃, 1040℃, 1050℃, 1060℃, 1070℃, 1080℃, 1090℃, or 1100℃, or any value within the range of 1000℃ to 1100℃. The time of the second heat treatment can be 40 min, 41 min, 42 min, 43 min, 44 min, 45 min, 46 min, 47 min, 48 min, 49 min, or 50 min, or any value within the range of 40 min to 50 min.
[0057] In some embodiments, the atmosphere for the second heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere. The inert gas atmosphere may be an argon atmosphere, etc.
[0058] Specifically, in this embodiment, the crude catalyst is heat-treated in a N2 atmosphere at 1000℃~1100℃ for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0059] Based on a general inventive concept, embodiments of this application also provide a catalyst, which is prepared using the method provided above.
[0060] The catalyst is prepared based on the above method. The specific steps of the method can be referred to the above embodiments. Since the catalyst adopts some or all of the technical solutions of the above embodiments, it has at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be repeated here.
[0061] Based on a general inventive concept, embodiments of this application also provide a membrane electrode, the membrane electrode including a cathode, the cathode including the catalyst provided above.
[0062] In some embodiments, the membrane electrode can be fabricated by transfer printing. Specifically, the anode can be fabricated using a commercially available Pt / C catalyst, and the cathode can be fabricated using the catalyst provided above. The Pt loading at the anode is 0.1 mg / cm³. 2 The cathode catalyst loading is 2.0–3.0 mg / cm³. 2(That is, 2.0-3.0 mg of Fe-Mn-N / C catalyst material is used per square centimeter of active area). Transfer temperature: 130-150℃, pressure: 1.2 MPa-2.0 MPa, holding time: 120-150 s.
[0063] The present application is further illustrated below with reference to specific embodiments. It should be understood that these embodiments are for illustrative purposes only and are not intended to limit the scope of the application. Experimental methods in the following embodiments that do not specify specific conditions are generally determined according to national standards. If there is no corresponding national standard, then general international standards, conventional conditions, or conditions recommended by the manufacturer are followed.
[0064] Example 1
[0065] A catalyst, the preparation process of which is as follows:
[0066] Iron and manganese nitrates (Fe and Mn molar ratio can be 1:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0067] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0068] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0069] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1000℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0070] Example 2
[0071] A catalyst, the preparation process of which is as follows:
[0072] Iron and manganese nitrates (Fe and Mn molar ratio can be 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0073] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0074] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0075] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1000℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0076] Example 3
[0077] A catalyst, the preparation process of which is as follows:
[0078] Iron and manganese nitrates (Fe and Mn molar ratio can be 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0079] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0080] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0081] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1050℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0082] Example 4
[0083] A catalyst, the preparation process of which is as follows:
[0084] Iron and manganese nitrates (Fe and Mn molar ratio can be 0.5:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidinic acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0085] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0086] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0087] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1000℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0088] Example 5
[0089] A catalyst, the preparation process of which is as follows:
[0090] Iron and manganese nitrates (Fe and Mn molar ratio can be 3:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0091] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0092] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0093] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1000℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0094] Example 6
[0095] A catalyst, the preparation process of which is as follows:
[0096] Iron and manganese nitrates (Fe and Mn molar ratio can be 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0097] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0098] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0099] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 950°C in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0100] Example 7
[0101] A catalyst, the preparation process of which is as follows:
[0102] Iron and manganese nitrates (Fe and Mn molar ratio can be 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0103] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0104] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0105] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1100℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0106] Example 8
[0107] A catalyst, the preparation process of which is as follows:
[0108] Iron and manganese nitrates (Fe and Mn molar ratio can be 2:1), sufficient nitrogen-rich organic precursors (nicarbazine and piperidine acid), and sufficient fumed silica (surface area ~150m²) are added. 2 Disperse (g) in water and mechanically mix until a thick, paste-like mixture is formed.
[0109] The mixture was dried at 90°C for 10 hours to obtain an intermediate powder.
[0110] The powder was then subjected to a first heat treatment, in which it was heat-treated at 950°C in a N2 atmosphere for 90 min. The powder was then soaked in a 25 wt.% HF solution for 24 h to remove silica impurities. Finally, it was thoroughly washed with water until the pH was approximately 6, thus obtaining the crude catalyst.
[0111] A second heat treatment was then performed, in which the crude catalyst was heat-treated at 1200℃ in a N2 atmosphere for 45 minutes to obtain the catalyst Fe-Mn-N / C.
[0112] Comparative Example 1
[0113] Tests were conducted on Pt / C catalyst particles of a certain brand sold in the market.
[0114] The physical properties of the catalysts provided in each embodiment and comparative example were tested, and the results are shown in the table below:
[0115]
[0116]
[0117] As shown in the table above, compared to the Pt / C catalyst, which has the best performance and is the most widely used in fuel cell membrane electrode assemblies, the non-Pt catalyst prepared in this application exhibits better performance in some aspects than commercially available Pt / C catalysts, such as surface area and pore size. Furthermore, since no precious metals are used, it has a significant cost advantage compared to Pt / C.
[0118] The catalysts provided in the various embodiments and comparative examples were used to prepare cathode catalytic layers and then to prepare membrane electrodes. The specific preparation process is as follows: Anodes were prepared using commercially available Pt / C catalysts, with a Pt loading of 0.1 mg / cm³. 2 The cathode catalyst loading is 2.0–3.0 mg / cm³. 2 The transfer temperature was 140℃, the pressure was 1.6MPa, and the holding time was 135s. The physical properties of each membrane electrode were tested, and the results are shown in the table below.
[0119]
[0120] As shown in the table above, compared with the Pt / C catalyst, which has the best performance and widest application in fuel cell membrane electrode assembly, the non-Pt catalyst prepared in this application has reached the level of Pt / C catalyst in terms of pore structure ratio and size.
[0121] The electrical performance of the membrane electrodes made from the catalysts provided in the various embodiments and comparative examples was tested, and the results are as follows: Figure 2 As shown in the figure, the power generation performance of the non-Pt catalysts (sample1 to sample8) has a clear correlation with the physicochemical properties of the catalysts. Furthermore, the performance of the non-Pt catalysts in this patent is quite close to that of existing commercial Pt / C catalysts. Additionally, since the Pt catalysts prepared in this patent do not use precious metal materials, they have a certain cost advantage.
[0122] Various embodiments of this application may exist in the form of a range; it should be understood that the description in the form of a range is merely for convenience and brevity and should not be construed as a hard limitation on the scope of this application; therefore, it should be considered that the range description has specifically disclosed all possible sub-ranges and single numerical values within that range. For example, it should be considered that the range description from 1 to 6 has specifically disclosed sub-ranges such as from 1 to 3, from 1 to 4, from 1 to 5, from 2 to 4, from 2 to 6, from 3 to 6, etc., and single numbers within the range, such as 1, 2, 3, 4, 5, and 6, regardless of the range. Furthermore, whenever a numerical range is referred to herein, it means including any referenced number (fraction or integer) within the referred range.
[0123] In this application, unless otherwise stated, directional terms such as "upper" and "lower" specifically refer to the drawing directions in the accompanying drawings. Furthermore, in the description of this application, terms such as "comprising" and "including" mean "including but not limited to." In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. In this document, "and / or" describes the relationship between related objects, indicating that three relationships can exist; for example, A and / or B can represent: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. In this document, "at least one" means one or more, and "more than one" means two or more. "At least one," "at least one of the following," or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of a, b or c" or "at least one of a, b and c" can both mean: a, b, c, ab (i.e. a and b), ac, bc, or abc, where a, b, and c can be a single or multiple.
[0124] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.
Claims
1. A method for preparing a Fe-Mn-N / C catalyst for a proton exchange membrane fuel cell, characterized in that, The method includes: Iron source, manganese source, nitrogen-rich organic precursor and silica are dispersed in solvent to obtain a mixed paste; The mixed paste is dried to obtain an intermediate powder; The intermediate powder is subjected to a first heat treatment, and then the silica in the intermediate powder after the first heat treatment is removed to obtain a crude catalyst. The crude catalyst was subjected to a second heat treatment to obtain the catalyst. The nitrogen-rich organic precursor includes at least one of nicarbazine and piperidine acid; The iron source includes iron; the manganese source includes manganese nitrate; the molar ratio of iron to manganese in the iron source and manganese source is (1~2):1; The temperature of the first heat treatment is 900℃~1000℃; the time of the first heat treatment is 80min~100min; The temperature of the second heat treatment is 1010℃~1100℃, and the time of the second heat treatment is 40min~50min.
2. The method for preparing the catalyst according to claim 1, characterized in that, The atmosphere for the second heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere.
3. The method for preparing the catalyst according to claim 1, characterized in that, The surface area of the silicon dioxide does not exceed 150m². 2 / g.
4. The method for preparing the catalyst according to claim 1, characterized in that, The drying temperature is 80℃~100℃; and / or The drying time is 8-12 hours.
5. The method for preparing the catalyst according to claim 1, characterized in that, The atmosphere for the first heat treatment is a nitrogen atmosphere and / or an inert gas atmosphere.
6. The method for preparing the catalyst according to claim 1, characterized in that, The silica in the intermediate powder is removed by immersion; and / or The soaking solution includes an HF solution; and / or The HF solution has a mass concentration of 20% to 30%; and / or The soaking time is 20h~28h.
7. A catalyst, characterized in that, The catalyst is prepared by the method according to any one of claims 1 to 6.
8. A membrane electrode, characterized in that, The membrane electrode includes a cathode, and the cathode includes the catalyst of claim 7.
9. The membrane electrode according to claim 8, characterized in that, The catalyst loading on the cathode is 2.0 mg / cm³. 2 ~3.0mg / cm 2 .