Boron-doped cobalt-based non-noble metal fuel cell oxygen reduction catalyst and preparation method thereof

Abstract

The invention discloses a boron-doped cobalt-based non-noble metal fuel cell oxygen reduction catalyst and a preparation method thereof, boron atoms are introduced into a Co center coordination environment to adjust the adsorption energy of active center oxygen species, and the intrinsic activity of the catalyst is improved; meanwhile, more internal active sites are exposed under the etching effect caused by decomposition of the uniformly dispersed boron source in the heat treatment process, so that the relatively high active center utilization rate is ensured; the preparation method disclosed by the invention is simple, low in cost and good in reproducibility, and the cobalt-based catalyst prepared on the basis of the method is higher in catalytic activity and better in stability compared with a leading non-noble metal catalyst.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and in particular relates to a boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst and a preparation method thereof. Background Art

[0002] Proton exchange membrane fuel cells (PEMFCs) use H2 and O2 / (air) as raw materials, generate electricity through redox reactions, and emit water as the product. They have the advantages of zero pollution and high energy conversion efficiency, and are an efficient and clean energy conversion technology. However, limited by the slow kinetics of the cathode oxygen reduction reaction, the demand for precious metal Pt-based catalysts in fuel cells remains high. However, the reserves of precious metal Pt on the earth are very limited, which is not conducive to the large-scale commercialization of fuel cells. Moreover, Pt-based catalysts are easily poisoned, and non-precious metal catalysts are highly tolerant to contamination by impurities such as carbon monoxide and ammonia. Compared with the path of continuing to reduce the Pt loading, the development of non-precious metal catalysts can fundamentally solve the problem of high catalyst prices. Therefore, the development of non-precious metal catalysts with both high activity and high stability is a hot topic currently focused on by the international frontier of energy chemistry.

[0003] Existing technologies improve the activity of non-precious metal catalysts by adjusting the coordination environment, electronic structure, developing new types of active sites, and increasing the density of active sites. However, the stability of such catalysts is still not ideal, and their performance in batteries decays rapidly. g -NC / Phen catalyst exhibited a high performance of 0.046 A·cm in 2 bar H2-O2 PEMFC. −2 High current density @ 0.9 V (iR-free), peak power density (P max ) reached an astonishing 1.53 and 0.711 W·cm −2, surpassing almost all reported platinum-free catalysts. However, after 30,000 cycles, the membrane electrode activity at 0.90 V decayed by 93.3%, and the fuel cell performance stability needs to be improved; in view of this difficulty, the rational design of high site density and high stability non-precious metal catalysts to achieve a synergistic improvement in activity and stability is the future development direction. Now some relatively mature strategies have been discovered, such as CVD method, multiple carbonization, introduction of anti-Fenton metals, addition of free radical scavengers, etc. Co-NC, as one of the most outstanding non-precious metal oxygen reduction catalysts, has a shorter bond length than Fe-N and higher potential stability. Modification by different means will help further improve its performance; Xiao et al. promoted the cleavage of OO bond by constructing FeCoN5-OH site, and the ORR half-wave potential was as high as 0.86 V (vs. RHE). The maximum power density of the proton exchange membrane fuel cell with this catalyst as the cathode reached 819 mW cm –2 , whose intrinsic activity is more than 20 times higher than that of single-atom FeN4 sites; He et al. developed a two-step Co-NC catalyst, which exhibits excellent oxygen reduction activity and stability in acidic media due to its high CoN4 active site density, optimized porosity and good mass transfer, as well as enhanced carbon corrosion resistance. The peak power density of H2-air proton exchange membrane fuel cells using this catalyst as cathode reached 0.39 W cm −2 ; Wu Gang's team reported a high-power and durable Co-NC nanofiber catalyst, which was constructed by electrospinning to form a unique porous fiber morphology and hierarchical structure. This exposed more accessible active sites, accelerated mass transfer, and improved the graphitization of the carbon matrix in the catalyst, greatly enhancing the corrosion resistance of the carbon, thereby promoting the stability of the catalyst. In the 1 bar H2-air proton exchange membrane fuel cell membrane electrode assembly test, it reached 0.40 W cm −2 The new 300W 3000M MOSFET has a peak power density of 1.18W and exhibits significantly enhanced durability in accelerated stability testing.

[0004] Although the activity and stability of the catalyst have been significantly improved after modification, there is still a certain gap between this type of research and the needs of practical application, and new solutions are urgently needed. In contrast, heteroatom boron doping with cobalt, nitrogen and carbon can effectively regulate the central atom adsorption energy on the basis of stabilizing the carbon skeleton to enhance the intrinsic activity.

[0005] Since the current doping modification under acidic conditions will destroy the stability of the original catalyst to a certain extent, such as the stability of the catalyst prepared by traditional second metal doping and large-radius non-metallic atom doping such as P and S, it is crucial to choose the appropriate doping ratio and method to ensure the synergistic improvement of catalyst activity and stability. Summary of the invention

[0006] The purpose of this section is to summarize some aspects of embodiments of the present invention and briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and the specification abstract and the invention title of this application to avoid blurring the purpose of this section, the specification abstract and the invention title, and such simplifications or omissions cannot be used to limit the scope of the present invention.

[0007] In view of the above problems and / or the problems existing in the prior art, the present invention is proposed.

[0008] Therefore, the purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for preparing a boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst.

[0009] In order to solve the above technical problems, the present invention provides the following technical solutions: a method for preparing a boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst is provided, comprising: Metal cobalt salt, metal zinc salt and 2-methylimidazole were dissolved in methanol and stirred to obtain a purple solid; The purple solid was separated by centrifugation, washed with methanol, dried and then heat treated under an inert atmosphere to obtain nitrogen-doped carbon rich in atomically dispersed cobalt; Atomically dispersed cobalt-rich nitrogen-doped carbon is used as a carrier, a boron source aqueous solution is added and stirred, and a catalyst precursor is obtained after rotary evaporation; The catalyst precursor is subjected to heat treatment to obtain a boron-doped high-stability cobalt-based fuel cell cathode catalyst; The metal cobalt salt is cobalt nitrate hexahydrate, the metal zinc salt is zinc nitrate hexahydrate, the molar ratio of the metal zinc salt to 2-methylimidazole is 1:5-8, and the molar ratio of the metal cobalt salt to the metal zinc salt is 1:20-50.

[0010] As a preferred embodiment of the preparation method of the present invention, the stirring is performed for 24 to 36 hours to obtain a purple solid.

[0011] As a preferred embodiment of the preparation method of the present invention, the purple solid is centrifuged at a speed of 10000-12000 rpm. As a preferred embodiment of the preparation method of the present invention, the centrifugation time of the purple solid is 3 to 8 minutes.

[0012] As a preferred embodiment of the preparation method of the present invention, the drying temperature is 50-80° C. and the drying time is 3-6 hours.

[0013] As a preferred embodiment of the preparation method of the present invention, the inert atmosphere is argon or nitrogen.

[0014] As a preferred embodiment of the preparation method of the present invention, the heating rate of the heat treatment is 1-10°C min -1 The heat treatment temperature is 900-950°C, and the heat treatment time is 1-2h.

[0015] As a preferred embodiment of the preparation method of the present invention, the boron source aqueous solution is an ammonium borate aqueous solution or a boric acid aqueous solution.

[0016] As a preferred embodiment of the preparation method of the present invention, the mass ratio of the boron source to nitrogen and carbon is 0.5-5:1.

[0017] Another object of the present invention is to overcome the deficiencies in the prior art and provide a boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst.

[0018] Beneficial effects of the present invention: 1. The method for preparing the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst provided by the present invention adjusts the adsorption energy of the active center oxygen species by introducing boron atoms into the Co center coordination environment to enhance the intrinsic activity.

[0019] 2. The etching effect brought about by the decomposition of the uniformly dispersed boron source during the heat treatment process of the present invention exposes more active sites inside, thereby ensuring a higher utilization rate of active centers.

[0020] 3. The preparation method of the present invention is simple, low-cost, and has good reproducibility. In addition, the cobalt-based catalyst prepared based on this method has higher catalytic activity and better stability than cutting-edge non-precious metal catalysts. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor. Among them: Figure 1 This is a transmission electron microscope image of the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention.

[0022] Figure 2 This is the N2 adsorption-desorption curve of the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention.

[0023] Figure 3 The stability test results of the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention in a three-electrode system.

[0024] Figure 4 The test results of a hydrogen-oxygen fuel cell assembled with the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention as the cathode.

[0025] Figure 5 The stability test results of a hydrogen-oxygen fuel cell assembled with the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention as the cathode.

[0026] Figure 6 The stability test results of a hydrogen-air fuel cell assembled with the boron-doped high-stability cobalt-based non-precious metal fuel cell cathode catalyst prepared in Example 1 of the present invention as the cathode. DETAILED DESCRIPTION

[0027] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with the embodiments of the specification.

[0028] In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0029] Secondly, the term "one embodiment" or "embodiment" as used herein refers to a specific feature, structure, or characteristic that may be included in at least one implementation of the present invention. The term "in one embodiment" that appears in different places in this specification does not necessarily refer to the same embodiment, nor does it refer to a separate or selective embodiment that is mutually exclusive with other embodiments.

[0030] Raw materials and reagents used in the present invention: 2-Methylimidazole (C4H6N2, 98%, McLean), zinc nitrate hexahydrate (Zn(NO3)2·6H2O, 99.99%, Aladdin), cobalt nitrate hexahydrate (Co(NO3)2·6H2O, 99.99%, Aladdin), cobalt chloride hexahydrate (CoCl3·6H2O, 99.99%, Aladdin), methanol (CH3OH, 99.5%, Xilong Chemical), ammonium borate (NH4HB4O7·3H2O, 99%, McLean), and boric acid (H3BO3, 99.5%, Aladdin).

[0031] Example 1

[0032] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 100 mg of cobalt nitrate hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 ºC min -1 The heat treatment temperature is 900 ºC for 1 h, and then it is cooled naturally to room temperature to obtain nitrogen-doped carbon rich in atomically dispersed cobalt sites, denoted as Zn 20 Co1-NC; 100 mg Zn 20 Co1-NC was dispersed in 30 mL ultrapure water, and 75 mg ammonium borate was added to ultrasonicate for 30 minutes, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 °C min -1 The heat treatment temperature is 900 ºC for 1 h, and after naturally cooling to room temperature, a boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst is obtained.

[0033] The catalyst was characterized by transmission electron microscopy. Figure 1 As shown, there are no obvious Co particles in the obtained catalyst and no obvious agglomeration occurs.

[0034] The catalyst was subjected to N2 adsorption and desorption test, and the results were as follows: Figure 2 As shown in Figure 2, the treated catalyst has a higher specific surface area (1084.485 m 2 g), which is conducive to exposing more catalytic active sites.

[0035] The catalyst of Example 1 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The results are as follows: Figure 3 As shown, the catalyst exhibits good oxygen reduction activity, with a half-wave potential of 0.82 V. After 30,000 cycles of accelerated aging test, the half-wave potential only decays by 19 mV, showing excellent stability.

[0036] The performance test was carried out by assembling a single cell with the catalyst of Example 1 as the cathode. The results are as follows: Figure 4 As shown, a fuel cell assembled with a boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst as the cathode is subjected to 1 bar H2-O2 and the cathode loading is 4 mg cm -2 Under these conditions, the peak power density can reach 823.77 mW cm -2, with excellent catalytic activity.

[0037] The boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst of Example 1 was used as the cathode to assemble a single cell for stability testing. The results are as follows: Figure 5 As shown, after 30,000 cycles of accelerated aging test in the potential range of 0.60 V to 0.95 V, the peak power density retention rate was 59.4%, indicating that the catalyst has good stability.

[0038] The catalyst of Example 1 was used as the cathode to assemble a single cell for stability testing. The results are as follows: Figure 6 The catalyst has better stability under hydrogen-air conditions, and after 30,000 cycles of accelerated aging tests, the peak power density retention rate is 69.1%.

[0039] Example 2

[0040] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 100 mg of cobalt nitrate hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 ºC min -1 The heat treatment temperature is 900 ºC for 1 h, and then it is cooled naturally to room temperature to obtain nitrogen-doped carbon rich in atomically dispersed cobalt sites, denoted as Zn 20 Co1-NC; 100 mg Zn 20 Co1-NC was dispersed in 30 mL ultrapure water, and 20.3 mg of boric acid was added and ultrasonicated for 30 minutes, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 °C min -1 The heat treatment temperature was 900 ºC for 1 h. After naturally cooling to room temperature, 90.1 mg of boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst was obtained.

[0041] The catalyst was characterized by transmission electron microscopy, and the results were similar to those in Example 1. No obvious Co particles were found in the obtained catalyst, and no obvious agglomeration occurred.

[0042] The catalyst of Example 2 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The results were similar to those of Example 1. The catalyst exhibited good oxygen reduction activity, with a half-wave potential of 0.80 V. After 30,000 cycles of accelerated aging testing, the half-wave potential decayed by 25 mV, demonstrating excellent stability.

[0043] Example 3

[0044] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 100 mg of cobalt nitrate hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 ºC min -1 The heat treatment temperature is 950 ºC for 1 h, and the heat treatment time is 1 h. After cooling to room temperature naturally, nitrogen-doped carbon rich in atomically dispersed cobalt sites is obtained, which is denoted as Zn 20 Co1-NC; 100 mg Zn 20 Co1-NC was dispersed in 30 mL ultrapure water, and 75 mg ammonium borate was added to ultrasonicate for 30 minutes, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 °C min -1 The heat treatment temperature was 950 ºC for 1 h. After naturally cooling to room temperature, 76.9 mg of boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst was obtained.

[0045] The catalyst was characterized by transmission electron microscopy, and the results were similar to those in Example 1. No obvious Co particles were found in the obtained catalyst, and no obvious agglomeration occurred.

[0046] The catalyst of Example 3 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The results were similar to those of Example 1. The catalyst exhibited good oxygen reduction activity, with a half-wave potential of 0.79 V. After 30,000 cycles of accelerated aging testing, the half-wave potential decayed by 15 mV, demonstrating excellent stability.

[0047] Example 4

[0048] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 100 mg of cobalt nitrate hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5°C min -1 The heat treatment temperature is 900 ºC for 1 h, and then it is cooled naturally to room temperature to obtain nitrogen-doped carbon rich in atomically dispersed cobalt sites, denoted as Zn 20 Co1-NC; 100 mg Zn 20 Co1-NC was dispersed in 30 mL ultrapure water, and 150 mg ammonium borate was added for 30 minutes of ultrasound, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 °C min -1 The heat treatment temperature was 900 ºC for 1 h. After naturally cooling to room temperature, 70.2 mg of boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst was obtained.

[0049] The catalyst was characterized by transmission electron microscopy, and the results were similar to those in Example 1. No obvious Co particles appeared in the obtained catalyst, and no obvious agglomeration occurred.

[0050] The catalyst of Example 4 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The results were similar to those of Example 1. The catalyst exhibited good oxygen reduction activity, with a half-wave potential of 0.79 V. After 30,000 cycles of accelerated aging testing, the half-wave potential decayed by 28 mV, demonstrating excellent stability. Comparative Example 1

[0051] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 80 mg of cobalt chloride hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5°C min -1The heat treatment temperature is 900 ºC for 1 h, and then it is cooled naturally to room temperature to obtain nitrogen-doped carbon rich in atomically dispersed cobalt sites, denoted as Zn 20 Co1-NC; 100 mg Zn 20 Co1-NC was dispersed in 30 mL ultrapure water, and 75 mg ammonium borate was added to ultrasonicate for 30 minutes, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5°C min -1 The heat treatment temperature was 900 ºC for 1 h. After naturally cooling to room temperature, 90.6 mg of boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst was obtained.

[0052] The catalyst was characterized by transmission electron microscopy, and the results were similar to those in Example 1. No obvious Co particles appeared in the obtained catalyst, and no obvious agglomeration occurred.

[0053] The catalyst of Example 5 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The result was slightly lower than that of Example 1. The catalyst showed general oxygen reduction activity, with a half-wave potential of 0.78 V. After 30,000 cycles of accelerated aging test, the half-wave potential decayed by 31 mV.

[0054] Comparative Example 2

[0055] Weigh 3.38 g of 2-methylimidazole and dissolve it in 40 mL of methanol and stir until it becomes clear, which is called solution A. Take another 2.02 g of zinc nitrate hexahydrate and 100 mg of cobalt nitrate hexahydrate in a 250 mL beaker, add 80 mL of methanol and stir until clear, which is called solution B; After the mixture of A and B was stirred for 24 h, it was washed three times by centrifugation with methanol and then dried in a drying oven at 55 °C to obtain a purple solid; The purple solid was placed in a tube furnace and heat treated in a 10% hydrogen-argon mixed atmosphere at a heating rate of 5°C min -1 The heat treatment temperature is 900 ºC for 1 h, and then it is cooled naturally to room temperature to obtain nitrogen-doped carbon rich in atomically dispersed cobalt sites, denoted as Zn 20 Co1-NC-H2; 100 mg Zn 20 Co1-NC-H2 was dispersed in 30 mL ultrapure water, and 150 mg ammonium borate was added for 30 minutes of ultrasound, followed by stirring at room temperature for 6 h. The resulting suspension was rotary evaporated to obtain the catalyst precursor; The precursor was placed in a tube furnace and heat treated in an argon atmosphere at a heating rate of 5 °C min -1 The heat treatment temperature was 900 ºC for 1 h. After naturally cooling to room temperature, 62.5 mg of boron-doped high-stability cobalt-based fuel cell cathode oxygen reduction catalyst was obtained.

[0056] The catalyst was characterized by transmission electron microscopy, and small-sized Co particles appeared in the obtained catalyst. Under this atmosphere, Co single atoms agglomerated.

[0057] The catalyst of Example 6 was subjected to an accelerated aging test in a 0.1 mol / L perchloric acid solution. The result was slightly lower than that of Example 1. The catalyst showed general oxygen reduction activity, with a half-wave potential of 0.79 V. After 30,000 cycles of accelerated aging testing, the performance decayed by 28 mV.

[0058] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst, characterized in that: include, Metal cobalt salt, metal zinc salt and 2-methylimidazole were dissolved in methanol and stirred to obtain a purple solid; The purple solid was separated by centrifugation, washed with methanol, dried and then heat treated under an inert atmosphere to obtain nitrogen-doped carbon rich in atomically dispersed cobalt; Atomically dispersed cobalt-rich nitrogen-doped carbon is used as a carrier, a boron source aqueous solution is added and stirred, and a catalyst precursor is obtained after rotary evaporation; The catalyst precursor is subjected to heat treatment to obtain a boron-doped high-stability cobalt-based fuel cell cathode catalyst; The metal cobalt salt is cobalt nitrate hexahydrate, the metal zinc salt is zinc nitrate hexahydrate, the molar ratio of the metal zinc salt to 2-methylimidazole is 1:5-8, and the molar ratio of the metal cobalt salt to the metal zinc salt is 1:20-50.

2. The preparation method according to claim 1, characterized in that: The stirring was continued for 24-36 h to obtain a purple solid.

3. The preparation method according to claim 1, characterized in that: The purple solid is centrifuged at a speed of 10000-12000 rpm.

4. The preparation method according to claim 1, characterized in that: The centrifugation time of the purple solid is 3 to 8 minutes.

5. The preparation method according to claim 1, characterized in that: The drying temperature is 50-80° C., and the drying time is 3-6 hours.

6. The preparation method according to claim 1, characterized in that: The inert atmosphere is argon or nitrogen.

7. The preparation method according to claim 1, characterized in that: The heating rate of the heat treatment is 1-10°C min -1 The heat treatment temperature is 900-950°C, and the heat treatment time is 1-2h.

8. The preparation method according to claim 1, characterized in that: The boron source aqueous solution is an ammonium borate aqueous solution or a boric acid aqueous solution.

9. The preparation method according to claim 8, characterized in that: The mass ratio of the boron source to nitrogen and carbon is 0.5-5:

1.

10. The boron-doped cobalt-based non-precious metal fuel cell oxygen reduction catalyst prepared by the preparation method according to any one of claims 1 to 9.

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