PEM water electrolysis hydrogen production catalyst material and preparation method thereof

Abstract

The invention relates to the field of preparation of catalysts, and particularly discloses a PEM water electrolysis hydrogen production catalyst material and a preparation method thereof, a manganese-cobalt-samarium metal composite oxide is used as a carrier, iridium oxide is loaded, and a unique catalyst composite material structure is formed. In the preparation process, by accurately adjusting the metal adding proportion and optimizing the technological parameters and the preparation sequence, the low iridium content is ensured, and the activity and stability of the catalyst are remarkably improved. The manganese-cobalt-samarium metal composite oxide has good conductivity, iridium oxide is crystallized on the substrate, electron binding can be effectively improved, binding sites are increased, and the oxygen adsorption capacity is optimized. The cost is effectively controlled while the catalyst composite material keeps high catalytic performance, and a solid foundation is laid for popularization and application.

Description

Technical Field

[0001] The present invention relates to the field of catalyst preparation, and specifically relates to a PEM water electrolysis hydrogen production catalyst material and a preparation method thereof. Background Art

[0002] PEM water electrolysis hydrogen production is a technology that uses a proton exchange membrane (PEM) to electrolyze water to produce hydrogen. This technology utilizes an electrochemical process to produce hydrogen by electrolyzing water while generating oxygen. Specifically, at the anode, water molecules are affected by an externally applied electric field and are electrolyzed into hydrogen ions and oxygen atoms. The oxygen atoms further combine to form oxygen and release electrons, and the generated oxygen is released into the gas phase through the gas diffusion layer of the anode; the hydrogen ions produced at the anode reach the cathode through the conduction of the proton exchange membrane (PEM). At the cathode, the hydrogen ions receive the electrons conducted from the anode through the external circuit, and the hydrogen ions combine with the electrons to form hydrogen. PEM water electrolysis hydrogen production technology has wide applications in fields such as hydrogen energy vehicles, hydrogen energy power stations, and hydrogen energy storage.

[0003] Generally, in the process of PEM water electrolysis hydrogen production, anode catalysts and cathode catalysts are required. Their main function is to accelerate the electrode reaction and reduce the activation energy of the reaction, thereby improving the electrolysis efficiency. Currently, the commercial anodic oxidation-reduction catalyst is mainly iridium oxide. However, the metal iridium is a non-renewable precious metal with a high price, which limits the large-scale industrial application of PEM water electrolysis. It is found that an OER catalyst with a low iridium content, high activity, and high stability is of great significance for reducing costs and saving resources. Summary of the Invention

[0004] The purpose of the present invention is to provide a PEM water electrolysis hydrogen production catalyst material and a preparation method thereof. The catalyst material uses a manganese-cobalt-samarium metal composite oxide as a carrier and loads iridium oxide. In the preparation process, by precisely adjusting the addition ratio of each metal, optimizing the preparation process parameters, and adjusting the preparation sequence, an oxygen evolution reaction (OER) catalyst with a low iridium content, high activity, and high stability is successfully prepared.

[0005] In order to achieve the above purpose, the technical solution adopted by the present invention is as follows:

[0006] A preparation method of a PEM water electrolysis hydrogen production catalyst material includes the following steps:

[0007] S1. Prepare a manganese-cobalt-samarium metal composite oxide:

[0008] Dissolve cobalt nitrate, manganese nitrate, samarium nitrate, and citric acid in water and stir for more than 12 h to obtain a first mixed solution;

[0009] Perform a redox reaction on the first mixed solution in a reaction kettle injected with air;

[0010] Filter the obtained reaction materials, wash them with deionized water, dry them, and grind them to obtain a manganese-cobalt-samarium metal composite oxide;

[0011] Among them, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 75-85:6-10:10-15.

[0012] S2. Perform iridium oxide loading:

[0013] Mix the manganese-cobalt-samarium metal composite oxide, iridium chloride, and water, and stir for more than 12 h;

[0014] After that, adjust the pH of the mixed solution to 9 or above;

[0015] After that, dry the solution, grind it to obtain the first powder;

[0016] Perform high-temperature calcination on the first powder, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material;

[0017] Among them, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5-3.

[0018] The present invention provides a preparation method of a PEM water electrolysis hydrogen production catalyst material, which uses a manganese-cobalt-samarium metal composite oxide as a carrier and loads iridium oxide to form a unique catalyst composite material structure. During the preparation process, by precisely adjusting the metal addition ratio, optimizing the process parameters and preparation sequence, not only the low iridium content is ensured, but also the activity and stability of the catalyst are significantly improved. The good conductivity of the manganese-cobalt-samarium metal composite oxide and the crystallization of iridium oxide on its substrate can effectively improve the electron binding, increase the binding sites, and optimize the oxygen adsorption capacity. While maintaining high catalytic performance, the catalyst composite material realizes effective cost control, laying a solid foundation for popularization and application.

[0019] Further, during the process of preparing the manganese-cobalt-samarium metal composite oxide in S1, the molar ratio of citric acid to cobalt nitrate added is 6-10:1.

[0020] Further, during the process of preparing the manganese-cobalt-samarium metal composite oxide in S1, the temperature of the redox reaction in the reaction kettle is 450 °C to 550 °C, and the reaction time is 30 min to 90 min.

[0021] Further, during the process of preparing the manganese-cobalt-samarium metal composite oxide in S1, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 80-85:8-10:10-12.

[0022] Further, during the preparation of the manganese-cobalt-samarium metal composite oxide in S1, stir for 12 h to 24 h.

[0023] Further, in S2, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5 to 2.

[0024] Further, in S2, the stirring time is 12 h to 24 h.

[0025] Further, in S2, calcine the first powder at a high temperature of 400°C - 600°C, and the high-temperature calcination time is 1 h to 3 h.

[0026] The second object of the present invention is to protect the catalyst material prepared by the above method.

[0027] The catalyst material prepared by using the above preparation method of the PEM water electrolysis hydrogen production catalyst material.

[0028] The third object of the present invention is to provide the application of the above catalyst material.

[0029] The application of the catalyst material as described above as an anode oxygen evolution catalyst in PEM water electrolysis.

[0030] In summary, due to the adoption of the above technical solutions, the beneficial effects of the present invention are as follows:

[0031] The present invention provides a preparation method of a PEM water electrolysis hydrogen production catalyst material, using a manganese-cobalt-samarium metal composite oxide as a carrier and loading iridium oxide to form a unique catalyst composite material structure. During the preparation process, by precisely adjusting the metal addition ratio, optimizing the process parameters and preparation sequence, not only is the low iridium content ensured, but also the activity and stability of the catalyst are significantly improved. The good conductivity of the manganese-cobalt-samarium metal composite oxide allows iridium oxide to crystallize on its substrate, which can effectively improve electron binding, increase binding sites, and optimize oxygen adsorption capacity. While maintaining high catalytic performance, the catalyst composite material effectively controls the cost, laying a solid foundation for popularization and application. Specific Embodiments

[0032] In order to make the objectives, technical solutions and advantages of the present invention clearer, the following embodiments are used to further elaborate on the present invention. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0033] Unless otherwise specified, in the description of the specific embodiments of the present invention, the expression terms indicating the orientation or positional relationship such as "upper", "lower", "left", "right", "center", "inner", "outer", etc. are all based on the expression of the orientation or positional relationship, or the orientation or positional relationship when the invention product / device / device is usually used. These terms of orientation or positional relationship are only for the convenience of describing the solution of the present invention or simplifying the description in the specific embodiments, so as to facilitate technicians to quickly understand the solution, rather than indicating or implying that a specific device / component / element must have a specific orientation, or be constructed and operated in a specific positional relationship. Therefore, it should not be construed as a limitation to the present invention.

[0034] In addition, if terms such as "horizontal", "vertical", "hanging", "parallel", etc. appear, it does not mean that the corresponding device / component / element is required to be absolutely horizontal or vertical or hanging or parallel, but can be slightly inclined or deviated. For example, "horizontal" only means that its direction is more horizontal relative to "vertical", and does not mean that the structure must be completely horizontal, but can be slightly inclined. Or, it can be simply understood that the corresponding device / component / element is arranged in the directions of "horizontal", "vertical", "hanging", "parallel", etc., and can have an error / deviation of ±10% relative to the corresponding direction setting, more preferably within ±8%, more preferably within ±6%, more preferably within ±5%, more preferably within ±4%. As long as the corresponding device / component / element is within the error / deviation range, it can still play its role in the solution of the present invention.

[0035] In addition, the expressions such as "first", "second", "third", etc. in the terms are only used to distinguish the description of the same or similar components, and should not be understood as emphasizing or implying the relative importance of specific components.

[0036] In addition, in the description of the embodiments of the present invention, "several", "multiple", "a plurality of" represent at least 2. It can be any situation such as 2, 3, 4, 5, 6, 7, 8, 9, etc., and even more than 9.

[0037] In addition, in the description of the technical solution of the present invention, unless otherwise clearly specified / defined / limited, where terms such as "set", "installed", "connected", "connected", "provided with", "laid", "arranged" appear, they should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection. It can be a connection means commonly used in the art such as welding, riveting, bolting, threaded connection, etc. This connection can be a mechanical connection, an electrical connection or a communication connection; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements.

[0038] Currently, the commercially available anodic oxidation-reduction catalyst is mainly iridium oxide. However, iridium metal is a non-renewable precious metal with a high price, which limits the large-scale industrial application of PEM water electrolysis. It has been found that an OER catalyst with a low iridium content, high activity and high stability is of great significance for reducing costs and saving resources.

[0039] The present invention provides a preparation method of a catalyst material for PEM water electrolysis to produce hydrogen. Iridium oxide is loaded on a manganese-cobalt-samarium metal composite oxide support. The manganese-cobalt-samarium metal composite oxide has good conductivity, and iridium oxide crystallizes on its substrate, effectively improving electron binding, increasing binding sites, and further optimizing oxygen adsorption capacity. These series of improvements enable the catalyst composite material to effectively control costs while maintaining high catalytic performance.

[0040] It includes the following steps:

[0041] S1. Prepare the manganese-cobalt-samarium metal composite oxide:

[0042] Dissolve cobalt nitrate, manganese nitrate, samarium nitrate and citric acid in water, stir for more than 12 h, and in some embodiments, stir for 12 h - 24 h to obtain a first mixed solution;

[0043] Carry out an oxidation-reduction reaction on the first mixed solution in a reaction kettle with air injection; the temperature of the oxidation-reduction reaction is 450 °C to 550 °C, and the reaction time is 30 min to 90 min.

[0044] Filter the obtained reaction material, wash it with deionized water, dry it, and grind it to obtain the manganese-cobalt-samarium metal composite oxide;

[0045] Among them, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 75 - 85:6 - 10:10 - 15.

[0046] In some embodiments, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 80 - 85:8 - 10:10 - 12. It has been found that the ratio control of cobalt, manganese, and samarium is a key factor affecting the performance of the entire catalyst material. Too small or too large a ratio will cause a significant decline in performance.

[0047] In some embodiments, the molar ratio of citric acid to cobalt nitrate added is 6 - 10:1. The main functions of citric acid are complexation, precipitation, and pH adjustment, etc.

[0048] S2. Carry out iridium oxide loading:

[0049] Mix the manganese-cobalt-samarium metal composite oxide, iridium chloride and water, stir for more than 12 h, and in some embodiments, stir for 12 h - 24 h to obtain a first mixed solution;

[0050] Afterwards, adjust the pH of the mixed solution to be above 9;

[0051] Afterwards, dry and grind the solution to obtain the first powder;

[0052] Calcine the first powder at a high temperature of 400 °C - 600 °C for 1 h - 3 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material;

[0053] Among them, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5 - 3. The mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is a key factor affecting the product performance. If the metal composite oxide is too little or too much, the effect improvement is not obvious. Preferably, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5 - 2.

[0054] Example 1

[0055] Preparation of catalyst material

[0056] S1. Preparation of manganese-cobalt-samarium metal composite oxide:

[0057] S11. Dissolve cobalt nitrate, manganese nitrate, samarium nitrate, and citric acid in water and stir for 15 h to obtain the first mixed solution; among them, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 80:8:10. The molar ratio of citric acid to added cobalt nitrate is 8:1, and the amount of added water is sufficient to completely dissolve cobalt nitrate and samarium nitrate.

[0058] S12. Conduct an oxidation-reduction reaction on the first mixed solution in a reaction kettle with injected air, where the reaction temperature is 500 °C and the reaction time is 60 min.

[0059] S13. Filter the obtained reaction material, wash it with deionized water, dry it, and grind it to obtain the manganese-cobalt-samarium metal composite oxide;

[0060] S2. Conduct iridium oxide loading:

[0061] S21. Mix the manganese-cobalt-samarium metal composite oxide, iridium chloride, and water and stir for 15 h; the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:2.

[0062] S22. Adjust the pH of the mixed solution to 9;

[0063] S23. Dry and grind the solution to obtain the first powder;

[0064] S24. Calcine the first powder at a high temperature of 500 °C for 2 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material.

[0065] Conduct performance tests:

[0066] Mix the mixed solution of Nafion solution, isopropanol and water in a ratio of 1:1, add the catalyst material to the mixed solution, mix evenly, and perform ball milling and ultrasonic treatment. At 75 °C, spray the catalyst suspension on polytetrafluoroethylene with an active area of 1 cm 2 , and record the loading amount of the catalyst material. Then transfer the sprayed catalyst material and the commercial cathode Pt / C catalyst to the proton exchange membrane.

[0067] After testing, in a three-electrode system, in a 0.6 M sulfuric acid solution saturated with oxygen, at a current density of 10 mA / cm 2 , the reaction overpotential of the oxygen evolution reaction is 211 mV; in the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 , it can operate stably for 3845 h.

[0068] Example 2

[0069] Prepare the catalyst material

[0070] S1. Prepare manganese-cobalt-samarium metal composite oxide:

[0071] S11. Dissolve cobalt nitrate, manganese nitrate, samarium nitrate and citric acid in water and stir for 12 h to obtain a first mixed solution; among them, the molar ratio of cobalt nitrate, manganese nitrate and samarium nitrate is 75:10:10, and the molar ratio of citric acid to cobalt nitrate added is 6:1. The amount of water added is sufficient to completely dissolve cobalt nitrate and samarium nitrate.

[0072] S12. Carry out redox reaction on the first mixed solution in a reaction kettle with air injection. The reaction temperature is 450 °C and the reaction time is 60 min.

[0073] S13. Filter the obtained reaction material, wash it with deionized water, dry it, and grind it to obtain manganese-cobalt-samarium metal composite oxide;

[0074] S2. Carry out iridium oxide loading:

[0075] S21. Mix manganese-cobalt-samarium metal composite oxide, iridium chloride and water and stir for 12 h; the mass ratio of manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5.

[0076] S22. Adjust the pH of the mixed solution to 11;

[0077] S23. Dry the solution and grind it to obtain the first powder;

[0078] S24. Calcinate the first powder at a high temperature of 400 °C for 3 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material.

[0079] For the catalyst material prepared in Example 2, performance testing was carried out using the same method as in Example 1. After testing, in a three-electrode system, in a 0.6 M sulfuric acid solution saturated with oxygen, at a current density of 10 mA / cm 2 the overpotential of the oxygen evolution reaction was 238 mV. In the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 it could operate stably for 3500 h.

[0080] Example 3

[0081] Preparation of catalyst material

[0082] S1. Preparation of manganese-cobalt-samarium metal composite oxide:

[0083] S11. Dissolve cobalt nitrate, manganese nitrate, samarium nitrate, and citric acid in water and stir for 24 h to obtain a first mixed solution; among them, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 85:6:15, and the molar ratio of citric acid to cobalt nitrate added is 10:1. The amount of water added should be sufficient to completely dissolve cobalt nitrate and samarium nitrate.

[0084] S12. Carry out an oxidation-reduction reaction on the first mixed solution in a reaction kettle with air injection. The reaction temperature is 550 °C and the reaction time is 90 min.

[0085] S13. Filter the obtained reaction material, wash it with deionized water, dry it, and grind it to obtain the manganese-cobalt-samarium metal composite oxide;

[0086] S2. Carry out iridium oxide loading:

[0087] S21. Mix the manganese-cobalt-samarium metal composite oxide, iridium chloride, and water and stir for 24 h; the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:3.

[0088] S22. Adjust the pH of the mixed solution to 9;

[0089] S23. Dry the solution and grind it to obtain the first powder;

[0090] S24. Calcinate the first powder at a high temperature of 600 °C for 3 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material.

[0091] For the catalyst material prepared in Example 3, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, at a current density of 10 mA / cm 2 the overpotential of the oxygen evolution reaction was 226 mV. In the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 it could operate stably for 3220 h.

[0092] Comparative Example 1

[0093] In the membrane electrode test for PEM water electrolysis to produce hydrogen, commercial iridium oxide was directly used as the catalyst.

[0094] For the catalyst material prepared from commercial iridium oxide in Comparative Example 1, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, in the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 it could operate stably for 123 h.

[0095] Comparative Example 2

[0096] Instead of a metal composite oxide, cobalt oxide was used as the carrier in Comparative Document 2.

[0097] The specific operation is as follows:

[0098] Preparation of catalyst material

[0099] S21. Mix cobalt oxide, iridium chloride and water, and stir for 15 h; the sum of the molar amounts of manganese, cobalt and samarium in the manganese-cobalt-samarium metal composite oxide in Example 1 is the added molar amount of cobalt oxide, and the mass of iridium chloride remains unchanged.

[0100] S22. Adjust the pH of the mixed solution to 9;

[0101] S23. Dry and grind the solution to obtain the first powder;

[0102] S24. Calcinate the first powder at 500 °C for 2 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material.

[0103] For the catalyst material prepared in Comparative Example 2, performance testing was carried out using the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, at a current density of 10 mA / cm², the overpotential of the oxygen evolution reaction was 315 mV. In the membrane electrode test, at a current density of 1 A*cm⁻² and an iridium loading of 0.5 mg*cm⁻², it could operate stably for 552 h.

[0104] Comparative Example 3

[0105] The carrier used in Comparative Document 3 is not a metal composite oxide, but samarium oxide.

[0106] The specific operation is as follows:

[0107] Preparation of catalyst material

[0108] S21. Mix samarium oxide, iridium chloride and water, and stir for 15 h; the sum of the molar amounts of manganese, cobalt and samarium in the manganese-cobalt-samarium metal composite oxide in Example 1 is the added molar amount of samarium oxide, and the mass of iridium chloride remains unchanged.

[0109] S22. Adjust the pH of the mixed solution to 9;

[0110] S23. Dry and grind the solution to obtain the first powder;

[0111] S24. Calcinate the first powder at 500 °C for 2 h, wash it with deionized water until neutral, dry it, and grind it to obtain the catalyst material.

[0112] For the catalyst material prepared in Comparative Example 3, performance testing was carried out using the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, at a current density of 10 mA / cm², the overpotential of the oxygen evolution reaction was 302 mV. In the membrane electrode test, at a current density of 1 A*cm⁻² and an iridium loading of 0.5 mg*cm⁻², it could operate stably for 618 h.

[0113] At the same time, in this specific method, the case of using only manganese oxide as the carrier was also done, and the performance of the prepared catalyst material was significantly degraded compared with that prepared in Example 1.

[0114] Comparative Example 4

[0115] In Comparative Example 4, the ratio of cobalt and samarium was adjusted. The following two groups of test processes are disclosed, namely Comparative Example 4-A and Comparative Example 4-B. In the following two groups of experimental processes, only the ratio of cobalt and samarium in the manganese-cobalt-samarium metal composite oxide was changed, and the iridium loading process was exactly the same as that in Example 1.

[0116] Among them, the process of preparing the manganese-cobalt-samarium metal composite oxide is the same as that in Example 1. The difference is that in Comparative Example 4-A, the molar ratio of cobalt nitrate to samarium nitrate is 80:30. In Comparative Example 4-B, the molar ratio of cobalt nitrate to samarium nitrate is 80:5; meanwhile, the total molar amount of manganese nitrate, cobalt nitrate and samarium nitrate is the same as that in Example 1.

[0117] For the catalyst material prepared in Comparative Example 4, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in a 0.6 M sulfuric acid solution saturated with oxygen, at a current density of 10 mA / cm 2 , the overpotential of the oxygen evolution reaction of the catalyst material in Comparative Example 4-A was 273 mV. In the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 , it could operate stably for 2150 h. The overpotential of the oxygen evolution reaction of the catalyst material in Comparative Example 4-B was 282 mV. In the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 , it could operate stably for 1887 h.

[0118] Comparative Example 5

[0119] In Comparative Example 5, the added mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride was changed. The following two groups of test processes were disclosed, namely Comparative Example 5-A and Comparative Example 5-B. In the following two experimental processes, only the added mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride was changed. The manganese-cobalt-samarium metal composite oxide prepared by the exactly same method as in Example 1 was used, and the operation process for iridium oxide loading was exactly the same as that in Example 1.

[0120] Among them, in Comparative Example 5-A, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride was 1:1. In Comparative Example 5-B, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride was 1:4.

[0121] For the catalyst material prepared in Comparative Example 5, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in a 0.6 M sulfuric acid solution saturated with oxygen, at a current density of 10 mA / cm 2 , the overpotential of the oxygen evolution reaction of the catalyst material in Comparative Example 5-A was 254 mV. In the membrane electrode test, at a current density of 1 A*cm -2 and an iridium loading of 0.5 mg*cm -2 , it could operate stably for 2400 h. The overpotential of the oxygen evolution reaction of the catalyst material in Comparative Example 5-B was 280 mV. In the membrane electrode test, at a current density of 1 A*cm -2Under the current density and an iridium loading of 0.5 mg·cm -2 , it can operate stably for 1700 h.

[0122] Comparative Example 6

[0123] In Comparative Example 6, the manganese-cobalt-samarium metal composite oxide prepared by the same method as in Example 1 was used, with the difference being the iridium oxide loading process.

[0124] In Comparative Example 6, the manganese-cobalt-samarium metal composite oxide and iridium chloride were physically stirred and thoroughly mixed to obtain the catalyst material.

[0125] For the catalyst material prepared in Comparative Example 6, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, at a current density of 10 mA / cm 2 , the overpotential of the oxygen evolution reaction was 324 mV. In the membrane electrode test, at a current density of 1 A·cm -2 and an iridium loading of 0.5 mg·cm -2 , it can operate stably for 460 h.

[0126] Comparative Example 7

[0127] In Comparative Example 7, the preparation process of the manganese-cobalt-samarium metal oxide was changed, and the iridium oxide loading process was exactly the same as in Example 1.

[0128] In Comparative Example 7, manganese oxide, cobalt oxide and iridium oxide were physically mixed to obtain the composite metal oxide.

[0129] For the catalyst material prepared in Comparative Example 7, the performance test was carried out by the same method as in Example 1. After testing, in a three-electrode system, in an oxygen-saturated 0.6 M sulfuric acid solution, at a current density of 10 mA / cm 2 , the overpotential of the oxygen evolution reaction was 355 mV. In the membrane electrode test, at a current density of 1 A·cm -2 and an iridium loading of 0.5 mg·cm -2 , it can operate stably for 240 h.

[0130] In the specific embodiment of the present application, physical mixing of three oxides was also carried out. Materials with samarium oxide loaded on a manganese-cobalt-iridium carrier and materials with cobalt oxide or manganese oxide loaded on a samarium-iridium carrier were prepared using the same raw material molar ratio as in Example 1. After performance testing, the effects were significantly poor.

[0131] This application uses manganese-cobalt-samarium metal composite oxide as a carrier, and iridium oxide is loaded to form a unique catalyst composite structure. During the preparation process, by precisely adjusting the metal addition ratio, optimizing the process parameters and preparation sequence, not only a low iridium content is ensured, but also the activity and stability of the catalyst are significantly improved, achieving remarkable results.

[0132] The above are only the preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of a PEM water electrolysis hydrogen production catalyst material, characterized in that, It includes the following steps: S1. Prepare manganese-cobalt-samarium metal composite oxide: Dissolve cobalt nitrate, manganese nitrate, samarium nitrate and citric acid in water and stir for more than 12 h to obtain a first mixed solution; Carry out a redox reaction on the first mixed solution in a reaction kettle into which air is injected; Filter the obtained reaction materials, wash them with deionized water, dry them, and grind them to obtain manganese-cobalt-samarium metal composite oxide; wherein, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 75-85:6-10:10-15. S2. Perform iridium oxide loading: Mix the manganese-cobalt-samarium metal composite oxide, iridium chloride and water and stir for more than 12 h; After that, adjust the pH of the mixed solution to be 9 or more; After that, dry the solution, grind it to obtain a first powder; Calcine the first powder at a high temperature, wash it with deionized water until it is neutral, dry it, and grind it to obtain a catalyst material; Wherein, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5-3.

2. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 1, characterized in that, During the preparation of the manganese-cobalt-samarium metal composite oxide in S1, the molar ratio of citric acid to cobalt nitrate added is 6-10:

1.

3. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 1, characterized in that, During the preparation of the manganese-cobalt-samarium metal composite oxide in S1, the temperature for the redox reaction in the reaction kettle is 450°C-550°C, and the reaction time is 30 min-90 min.

4. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 1, characterized in that, During the preparation of the manganese-cobalt-samarium metal composite oxide in S1, the molar ratio of cobalt nitrate, manganese nitrate, and samarium nitrate is 80-85:8-10:10-12.

5. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 1, characterized in that, During the preparation of the manganese-cobalt-samarium metal composite oxide in S1, stir for 12 h-24 h.

6. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to any one of claims 1-5, characterized in that, In S2, the mass ratio of the manganese-cobalt-samarium metal composite oxide to iridium chloride is 1:1.5-2.

7. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 6, characterized in that, In S2, the stirring time is 12 h-24 h.

8. The preparation method of the PEM water electrolysis hydrogen production catalyst material according to claim 7, characterized in that, In S2, calcine the first powder at a high temperature of 400°C-600°C, and the high-temperature calcination time is 1 h-3 h.

9. A catalyst material prepared by using the preparation method of the PEM water electrolysis hydrogen production catalyst material according to any one of claims 1-8.

10. Application of the catalyst material according to claim 9 as an anode oxygen evolution catalyst in PEM water electrolysis.