Carbon-loaded platinum-based ternary alloy catalyst as well as preparation and application thereof

Abstract

The invention relates to a carbon-loaded platinum-based ternary alloy catalyst and preparation and application thereof, the preparation method of the catalyst comprises the following steps: S1, dispersing a carbon carrier, a platinum-containing compound solution and a soluble metal salt solution of cobalt and nickel into ethylene glycol to obtain a ternary precursor suspension; and S2, adding a precipitator into the ternary precursor suspension, stirring, reacting in a microwave reactor, separating a product, washing and drying to obtain the carbon-loaded platinum-based ternary alloy catalyst. The preparation method has the characteristics of rapidness, simplicity and convenience, and is convenient for batch production; meanwhile, under the microwave reaction condition, Ni is used for promoting the activity of the Pt catalyst, Co and Ni are used for cooperatively regulating and controlling the particle size and dispersity of the catalyst, and the efficient synergistic effect of ternary metal under the microwave effect is achieved. The prepared PtCoNi ternary alloy catalyst is lower in noble metal content, moderate in particle size, uniform in dispersion, high in catalytic activity, good in stability and suitable for oxygen reduction reaction of fuel cells.

Description

Technical Field

[0001] This invention belongs to the field of fuel cell catalyst technology, and relates to a carbon-supported platinum-based ternary alloy catalyst and its preparation and application. Background Technology

[0002] Fuel cell technology has a wide range of applications, covering automobiles, aviation, energy storage, power generation, and marine industries. Among them, proton exchange membrane fuel cells (PEMFCs) have always been a research hotspot due to their high energy efficiency, environmental friendliness, fast start-up speed, and safe and reliable operation. Catalysts, as key materials in fuel cells, directly affect the overall performance of the fuel cell due to their cost and performance. Currently, platinum (Pt) remains the dominant catalyst. To reduce catalyst costs and the amount of Pt used, Pt is often alloyed with transition metals such as Fe, Co, and Ni, utilizing ligand effects and stress effects to improve catalytic performance. Both of these effects can shift the d-band center of Pt atoms downwards, weakening the binding energy between Pt and oxygen-containing intermediates, thereby improving catalytic activity while reducing the amount of Pt used.

[0003] Pt-based alloy catalysts are expected to become the mainstream oxygen reduction catalysts in future commercial fuel cells. While binary Pt-based alloy catalysts can improve catalytic performance to some extent in the oxygen reduction reaction of fuel cells by introducing a second element to regulate the active sites, they suffer from disadvantages such as difficulty in balancing activity and stability, high dependence on precious metals, weak resistance to poisoning, and limited room for structural optimization. Furthermore, the harsh operating environment of fuel cells (high voltage of 0.6-1.0V and strong acidity) makes the transition metals in binary alloy catalysts prone to oxidation, dissolution, and loss. This not only weakens the ligand and stress effects brought about by alloying, reducing catalytic activity, but may also shorten the lifespan of the membrane electrode assembly (MEA) due to the corrosion and poisoning resistance caused by the dissolved metal ions. In contrast, ternary catalysts, with their synergistic effect of multiple components, can not only more efficiently improve activity and enhance corrosion and poisoning resistance, but also significantly reduce the amount of precious metals used. They also possess advantages in multifunctional integration and long-life design, making them more competitive in terms of performance and cost, and a key direction for promoting the development of fuel cell technology. Therefore, developing efficient, stable, and functionalized ternary alloy catalysts is crucial for advancing fuel cell technology.

[0004] For example, Chinese patent application CN202010411503.3 provides a microwave preparation method for a binary alloy catalyst for fuel cells, including the following steps: (1) dispersing a carbon support, a platinum-containing compound solution, and a transition metal salt solution in ethylene glycol, and dispersing them evenly by ultrasonication or stirring to obtain a binary precursor suspension; (2) adding additives and precipitants to the binary precursor suspension prepared in step (1) and stirring, then heating it to boiling in a microwave oven, cooling it to room temperature, and letting it stand for 0.1-24 hours; (3) adding an acid solution to the mixture in step (2), letting it stand for 0.1-100 hours, then washing it by centrifugation or pressure filtration, and drying it by blowing air at 30-90°C to obtain the binary alloy catalyst. However, this binary alloy catalyst still needs further improvement in terms of catalyst particle size and dispersibility, as well as the balance between catalytic activity and stability. Summary of the Invention

[0005] The purpose of this invention is to provide a carbon-supported platinum-based ternary alloy catalyst, its preparation and application, to reduce the amount of precious metals used in fuel cells, thereby lowering costs, while simultaneously controlling the particle size and dispersion of the ternary alloy catalyst to improve oxygen reduction catalytic activity and stability. This invention utilizes Ni to promote the activity of Pt nanocatalysts under microwave reaction conditions, while simultaneously using Co and Ni to synergistically control the catalyst particle size and dispersion, achieving a highly efficient synergistic effect of ternary metals under microwave irradiation.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] In one aspect, the present invention provides a method for preparing a carbon-supported platinum-based ternary alloy catalyst, comprising the following steps:

[0008] S1. Disperse the carbon support, platinum-containing compound solution, and soluble metal salt solutions of cobalt and nickel into ethylene glycol to obtain a ternary precursor suspension.

[0009] S2. A precipitant was added to the ternary precursor suspension and stirred. The mixture was then reacted in a microwave reactor. The product was then separated, washed, and dried to obtain a carbon-supported platinum-based ternary alloy catalyst.

[0010] Furthermore, in S1, the carbon support is XC-72R or EC300J.

[0011] Furthermore, in S1, the platinum-containing compound used is chloroplatinic acid. Preferably, the concentration of the provided chloroplatinic acid solution is 0.1–1 mol / L.

[0012] Furthermore, in S1, the soluble metal salts of cobalt and nickel used are nitrates or hydrochlorides. Specifically, the soluble metal salt of cobalt can be cobalt nitrate or cobalt chloride; while the soluble metal salt of nickel can be nickel nitrate or nickel chloride. In addition, the concentration of the soluble metal salt can be 0.1–1 mol / L.

[0013] In addition, the solvent used in platinum-containing compound solutions and soluble metal salt solutions can be ethylene glycol and / or water. When it is a mixture of ethylene glycol and water, the volume ratio of water to ethylene glycol is not greater than 10:1.

[0014] Furthermore, in S1, the ratio of carbon support, platinum-containing compound, soluble metal salt of cobalt, and soluble metal salt of nickel is (40–80) mg: (0.05–0.11) mmol: (0.01–0.022) mmol: (0.05–0.11) mmol.

[0015] Furthermore, in S2, the precipitant is potassium hydroxide or sodium hydroxide, and its addition amount satisfies the pH value of the solution system being 11.5 to 12.5, preferably around 12.

[0016] Furthermore, in S2, the microwave reaction conditions are: power of 80-800W and time of 0.5-30min.

[0017] Furthermore, the process of separating the product and washing and drying it specifically involves:

[0018] After the reaction is complete, let it stand and cool for 30 minutes, then separate the reaction product, add it to a 0.01-0.5 mol / L perchloric acid solution, let it stand for 30-60 minutes, separate it again, and dry it under vacuum.

[0019] In a second aspect, the present invention provides a carbon-supported platinum-based ternary alloy catalyst, which is prepared by the preparation method described in the first aspect above. In the carbon-supported platinum-based ternary alloy catalyst, the alloy particles are supported on the edge of the carbon support and have an average particle size of 2 to 3 nm.

[0020] In a third aspect, the present invention provides an application of a carbon-supported platinum-based ternary alloy catalyst in oxygen reduction reactions.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] (1) By combining microwave-assisted reduction with the reduction of ethylene glycol, a ternary alloy catalyst is obtained by simultaneous reduction of multiple metal ions. The process is simple and time-saving.

[0023] (2) By using two relatively inexpensive transition metals and platinum alloy, the amount of precious metals used is reduced, thus saving the cost of the catalyst.

[0024] (3) Compared with binary alloy catalysts, ternary alloy catalysts can better control the performance of the catalyst, including the particle size, dispersibility, activity and stability. Under microwave reaction conditions, this invention utilizes Ni to promote the activity of Pt nanocatalysts, and at the same time utilizes Co and Ni to synergistically control the particle size and dispersibility of the catalyst, thus realizing the efficient synergistic effect of ternary metals under microwave action.

[0025] (4) The obtained ternary alloy catalyst has a moderate particle size, uniform dispersion, high catalytic activity, and good stability. In the oxygen reduction reaction (ORR), it is superior to commercial platinum-carbon catalyst. Attached Figure Description

[0026] Figure 1 XRD comparison diagrams of the catalysts prepared in Examples 1, 2, and 3 and 20% commercial platinum-carbon catalyst (TANAKA).

[0027] Figure 2a The image shows a TEM image of the PtCoNi ternary alloy catalyst prepared in Example 1.

[0028] Figure 2b TEM image of 20% commercial platinum-carbon catalyst (TANAKA).

[0029] Figure 2c TEM image of the PtNi binary alloy catalyst prepared for Comparative Example 1.

[0030] Figure 2d TEM image of the PtCo binary alloy catalyst prepared for Comparative Example 2.

[0031] Figure 2e TEM image of the PtCoNi ternary alloy catalyst prepared for Comparative Example 4.

[0032] Figure 3 Comparison of ORR linear voltammetric scan curves for the catalysts prepared in Examples 1, 2, and 3 and for 20% commercial platinum-carbon catalyst (TANAKA).

[0033] Figure 4 The ORR linear voltammetric scan curves of Example 1, Comparative Examples 1, 2, 3, and 20% commercial platinum-carbon catalyst (TANAKA) are shown in the figure.

[0034] Figure 5 The ORR linear voltammetric scan curves of the PtCoNi ternary alloy catalyst prepared in Comparative Example 5 and the catalyst prepared in Example 1 are shown as a comparison.

[0035] Figure 6 This is a comparison of the ORR linear voltammetric scan curves before and after accelerated durability testing in Example 1.

[0036] Figure 7 This is a comparison of the ORR linear voltammetric scan curves before and after accelerated durability testing, as shown in Comparative Example 1.

[0037] Figure 8 This is a comparison of the ORR linear voltammetric scan curves before and after accelerated durability testing, as shown in Comparative Example 2.

[0038] Figure 9 Comparison of ORR linear voltammetric scan curves before and after accelerated durability testing for a 20% commercial platinum-carbon catalyst (TANAKA). Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0040] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0041] As used herein, the terms "and / or," "or / and," and "and / or" encompass any one of two or more of the related listed items, as well as any and all combinations of the related listed items. These arbitrary and all combinations include any two related listed items, any more related listed items, or a combination of all related listed items. It should be noted that when at least three items are connected using at least two conjunctions selected from "and / or," "or / and," and "and / or," it should be understood that, in this application, the technical solution undoubtedly includes solutions connected by "logical AND," and also undoubtedly includes solutions connected by "logical OR."

[0042] In this application, the technical features described in an open-ended manner include both closed technical solutions consisting of the listed features and open technical solutions that include the listed features.

[0043] In this application, numerical ranges are referred to as continuous unless otherwise specified, and include the minimum and maximum values ​​of the range, as well as every value between the minimum and maximum values. Furthermore, when the range refers to integers, it includes every integer between the minimum and maximum values ​​of the range. Additionally, when multiple ranges are provided to describe a feature or characteristic, the ranges may be merged. In other words, unless otherwise specified, all ranges disclosed herein should be understood to include any and all subranges to which they are incorporated.

[0044] This document only specifically discloses some numerical ranges. However, any lower limit can be combined with any upper limit to form an unspecified range; and any lower limit can be combined with other lower limits to form an unspecified range, just as any upper limit can be combined with any other upper limit to form an unspecified range. Furthermore, each individually disclosed point or single value can itself serve as a lower or upper limit and be combined with any other point or single value or with other lower or upper limits to form an unspecified range.

[0045] Unless otherwise specified, the temperature parameters in this application may be either constant temperature processing or processing within a certain temperature range. The constant temperature processing allows temperature fluctuations within the precision range controlled by the instrument, such as ±5℃, ±4℃, ±3℃, ±2℃, or ±1℃.

[0046] In this document, the term "suitable" as used in phrases such as "suitable combination," "suitable method," and "any suitable method" refers to the ability to implement the technical solution of this application, solve the technical problem of this application, and achieve the expected technical effect of this application.

[0047] In this application, terms such as "further," "even further," and "particularly" are used to describe purposes and indicate differences in content, but should not be construed as limiting the scope of protection of this application.

[0048] In this application, "optionally," "optionally," and "optional" mean that something is optional, that is, it means that it is selected from either "with" or "without." If there are multiple "optional" entries in a technical solution, unless otherwise specified, and there are no contradictions or mutual constraints, each "optional" entry shall be independent.

[0049] In the description of the application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0050] Unless otherwise specified, all preparations and tests described herein took place at 25°C.

[0051] The terms “comprising,” “including,” “containing,” “having,” “comprising,” or other variations thereof are intended to cover non-closed inclusion, and no distinction is made between these terms. The term “comprising” means that other steps and ingredients may be added without affecting the final result. The compositions and methods / processes of the present invention comprise, consist of, and substantially consist of the essential elements and limitations described herein, as well as any additional or optional ingredients, components, steps, or limitations described herein. No distinction is made between the terms “efficacy,” “performance,” “effect,” and “potency” herein.

[0052] Unless otherwise specified, all embodiments and optional embodiments of this application can be combined to form new technical solutions. Unless otherwise specified, all technical features and optional technical features of this application can be combined to form new technical solutions.

[0053] Unless otherwise specified, all steps of this application may be performed sequentially or randomly, but sequentially is preferred.

[0054] In the following examples or comparative examples, chloroplatinic acid, potassium hydroxide, sodium hydroxide, ethylene glycol, cobalt nitrate, nickel nitrate, copper nitrate, etc., were purchased from Shanghai Maclean Biochemical Technology Co., Ltd., and other raw materials or processing technologies not specifically mentioned are all conventional commercially available products or conventional processing technologies in the field.

[0055] Preparation method of working electrode: Weigh 4 mg of the prepared catalyst material using an analytical balance, disperse it in 1 mL of a mixed solution of deionized water and ethanol (volume ratio of 4:1), add 20 μL of 5% Nafion solution, and sonicate for 30 min to obtain catalyst slurry. Take 10 μL and drop it onto a rotating disc glassy carbon electrode with a diameter of 5 mm. Dry it and let it air dry naturally before using it as the working electrode.

[0056] ORR assay method: In an oxygen-saturated 0.1 mol / L perchloric acid solution, a platinum sheet was used as the counter electrode, a saturated calomel electrode as the reference electrode, and a rotating disk glassy carbon electrode coated with catalyst was used as the working electrode. The test was conducted at 1600 rpm, and data were collected to obtain a linear voltammetric scan curve of ORR. Electrochemical data were collected using a CHI760E (Shanghai Chenhua).

[0057] Example 1:

[0058] Preparation of PtCoNi ternary alloy catalyst: Weigh 40 mg of XC-72R carbon support, measure 510 μL of 0.1 mol / L ethylene glycol solution of chloroplatinic acid, 102 μL of 0.1 mol / L ethylene glycol solution of cobalt nitrate, and 510 μL of 0.1 mol / L ethylene glycol solution of nickel nitrate, add them to 40 mL of ethylene glycol, sonicate for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the catalyst powder.

[0059] Example 2:

[0060] Preparation of PtCoNi ternary alloy catalyst (modified carbon support): Weigh 40 mg of EC300J carbon support, measure 510 μL of 0.1 mol / L chloroplatinic acid in ethylene glycol solution, 102 μL of 0.1 mol / L cobalt nitrate in ethylene glycol solution, and 510 μL of 0.1 mol / L nickel nitrate in ethylene glycol solution, add to 40 mL of ethylene glycol, ultrasonically disperse for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W power for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the catalyst powder.

[0061] Example 3:

[0062] Preparation of PtCoNi ternary alloy catalyst (increasing reaction amount, changing microwave reaction power and time): Weigh 80 mg of XC-72R carbon support, measure 510 μL of 0.2 mol / L ethylene glycol solution of chloroplatinic acid, 102 μL of 0.2 mol / L ethylene glycol solution of cobalt chloride, and 510 μL of 0.2 mol / L ethylene glycol solution of nickel chloride, add them to 80 mL of ethylene glycol, ultrasonically disperse for 30 min, then add sodium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 300 W power for 30 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 40 mL of 0.5 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the catalyst powder.

[0063] Comparative Example 1:

[0064] Preparation of PtNi binary alloy catalyst: Weigh 40 mg of XC-72R carbon support, add 510 μL of 0.1 mol / L chloroplatinic acid solution in ethylene glycol and 102 μL of 0.1 mol / L nickel nitrate solution in ethylene glycol to 40 mL of ethylene glycol, sonicate for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the PtNi binary alloy catalyst powder.

[0065] Comparative Example 2:

[0066] Preparation of PtCo binary alloy catalyst: Weigh 40 mg of XC-72R carbon support, add 510 μL of 0.1 mol / L chloroplatinic acid in ethylene glycol solution and 102 μL of 0.1 mol / L cobalt nitrate in ethylene glycol solution to 40 mL of ethylene glycol, sonicate for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the PtCo binary alloy catalyst powder.

[0067] Comparative Example 3:

[0068] Preparation of PtCu binary alloy catalyst: Weigh 40 mg of XC-72R carbon support, add 510 μL of 0.1 mol / L chloroplatinic acid solution in ethylene glycol and 102 μL of 0.1 mol / L copper nitrate solution in ethylene glycol to 40 mL of ethylene glycol, sonicate for 30 min, then add sodium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the PtCu binary alloy catalyst powder.

[0069] Comparative Example 4:

[0070] Preparation of PtCoNi ternary alloy catalyst (hydrothermal synthesis method): Weigh 40 mg of XC-72R carbon support, measure 510 μL of 0.1 mol / L ethylene glycol solution of chloroplatinic acid, 102 μL of 0.1 mol / L ethylene glycol solution of cobalt nitrate, and 510 μL of 0.1 mol / L ethylene glycol solution of nickel nitrate, add them to 40 mL of ethylene glycol, sonicate for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, transfer the reaction solution to a reaction vessel, and hydrothermally react at 160 °C for 10 h. After cooling, filter and wash the reaction solution under reduced pressure, add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, and dry in a vacuum drying oven at 60 °C for 30 min to collect the catalyst powder.

[0071] Comparative Example 5:

[0072] Preparation of PtCoNi ternary alloy catalyst (with altered metal ratio): Weigh 40 mg of XC-72R carbon support, measure 510 μL of 0.1 mol / L ethylene glycol solution of chloroplatinic acid, 510 μL of 0.1 mol / L ethylene glycol solution of cobalt nitrate, and 510 μL of 0.1 mol / L ethylene glycol solution of nickel nitrate, add them to 40 mL of ethylene glycol, ultrasonically disperse for 30 min, then add potassium hydroxide solution to adjust the pH to about 12, stir and mix for 30 min, place in a microwave reactor, react at 400 W for 10 min, then let stand and cool for 30 min, filter under reduced pressure and wash, then add 20 mL of 0.1 mol / L perchloric acid solution, let stand for 30 min, filter under reduced pressure, dry in a vacuum drying oven at 60 °C for 30 min, and collect the catalyst powder.

[0073] Figure 1 The XRD diffraction patterns of the catalysts prepared in Examples 1, 2, and 3 are shown, along with a comparison with a 20% commercial platinum-carbon catalyst (TANAKA). The characteristic peaks at 39.8° and 46.2° correspond to the (111) and (200) crystal planes of platinum, respectively. Compared with the 20% commercial platinum-carbon catalyst (TANAKA), the diffraction peaks of the catalysts prepared by the method of this invention are all shifted to the right to a certain extent. This is because nickel and cobalt have small atomic radii and will be incorporated into the platinum lattice, resulting in the corresponding diffraction peaks shifting to the right. In addition, no separate diffraction peaks of metallic nickel or cobalt were observed in the XRD diffraction patterns of the catalysts prepared in Examples 1, 2, and 3. The XRD patterns demonstrate that the method of this invention can prepare ternary alloy catalysts of PtCoNi.

[0074] Figure 2a and Figure 2b These are TEM images of Example 1 and a 20% commercial platinum-carbon catalyst, obtained by... Figure 2a and Figure 2b The comparison shows that the ternary alloy catalyst prepared by the method of the present invention has a moderate particle size (2-3 nm), a more uniform distribution, and no agglomeration. Furthermore, compared to a 20% commercial platinum-carbon catalyst, the alloy particles prepared by this method are loaded at the edges of the carbon particles, which better exposes the active sites, thus improving catalytic performance.

[0075] Figure 2c and Figure 2dThe images show TEM images of the PtNi binary alloy catalyst in Comparative Example 1 and the PtCo binary alloy catalyst in Comparative Example 2. It can be seen that the PtNi binary alloy catalyst has a larger particle size (3-10 nm) and is unevenly dispersed, exhibiting an agglomerate state. While the PtCo binary alloy catalyst also has relatively uniform dispersion, its particle size is too small (<1 nm), which is detrimental to the catalyst's adhesion to the carbon support and the stability during the catalytic reaction. Therefore, under microwave conditions, the PtCoNi ternary alloy catalyst balances particle size and dispersion, thus improving catalytic performance.

[0076] Figure 2e The image shows a TEM image of the PtCoNi ternary alloy catalyst prepared by the hydrothermal method in Comparative Example 4, compared with that in Example 1. Figure 2a The comparison clearly shows that the ternary alloy particles prepared by the hydrothermal method exhibit severe agglomeration and extremely uneven distribution, with catalyst particles ranging in size from 1 to 20 nm. This result indicates that, unlike microwave conditions, under hydrothermal conditions, Co and Ni in the PtCoNi ternary alloy catalyst cannot play a role in regulating catalyst particle size and dispersion. This further demonstrates the differences in the roles and mechanisms of Co and Ni under hydrothermal and microwave conditions.

[0077] Figure 3 This is a comparison of ORR linear voltammetric scans for Examples 1, 2, and 3 with a 20% commercial platinum-carbon catalyst (TANAKA). Figure 3 It can be seen that the preparation method of this invention has little impact on the performance of the catalyst by adjusting the reaction power and time within a certain range, and the onset potential (~1.03V vs. RHE) and half-wave potential (~0.90V vs. RHE) are both superior to those of a 20% commercial platinum-carbon catalyst (TANAKA, onset potential ~0.96V vs. RHE, half-wave potential ~0.85V vs. RHE). Therefore, the microwave-assisted method for preparing PtCoNi ternary alloy catalysts has good applicability and low requirements for microwave reaction conditions.

[0078] Figure 4 This is a comparison of the ORR linear voltammetric scan curves of Example 1 with Comparative Examples 1, 2, and 3, and 20% commercial platinum-carbon catalyst (TANAKA). From... Figure 4As can be seen, the ORR performance of binary alloy catalysts such as PtCo, PtNi, and PtCu alloys in the comparative examples is lower than that of the PtCoNi ternary alloy catalyst synthesized by this method, indicating that the PtCoNi ternary alloy catalyst synthesized in this invention has superior performance in ORR catalysis compared to binary alloy catalysts. Furthermore, the ORR activity of the binary alloy catalysts prepared by this method is PtNi > PtCu > PtCo. PtNi alloy catalysts have good catalytic activity, but their particles are large and poorly dispersed, affecting further improvement of catalytic performance; PtCo alloy catalysts have uniform particle dispersion, but their catalytic activity is relatively low. The PtCoNi ternary alloy catalyst combines the advantages of both PtNi and PtCo binary alloy catalysts, exhibiting optimal catalytic activity.

[0079] Figure 5 The ORR linear voltammetric scan curves of the PtCoNi ternary alloy catalysts prepared in Comparative Example 5 and Example 1 were compared. The results show that increasing the Co content leads to a decrease in the onset potential and half-wave potential, thereby reducing the ORR catalytic activity. Therefore, the ratio of the three metals must be strictly controlled when preparing ternary alloy catalysts. The metal ratio used in this invention has been experimentally optimized and exhibits excellent catalytic performance.

[0080] Figure 6 , 7 Tables 8 and 9 are comparative graphs of the ORR linear voltammetric scans of Example 1, Comparative Example 1, Comparative Example 2, and the 20% commercial platinum-carbon catalyst (TANAKA) before and after accelerated durability testing. Accelerated durability testing was conducted under nitrogen saturation conditions within a specific potential range (0.6-1.0 V vs. RHE) using continuous cyclic voltammetric scans at a scan rate of 400 mV / s for 10,000 cycles. The ORR linear voltammetric curves before and after the scans were compared, and the change in half-wave potential before and after the scans was used to illustrate the stability of the catalyst. Figure 6 As can be seen from the data, the PtCoNi ternary alloy catalyst prepared by this method in Example 1 not only has the highest initial catalytic activity, but also only decreased by 10 mV after 10,000 scans. In contrast, the half-wave potential of Comparative Example 1, Comparative Example 2, and the commercial platinum-carbon catalyst decreased by 12 mV, 23 mV, and 28 mV, respectively. The degree of reduction is greater than that of the PtCoNi ternary alloy catalyst synthesized by this method, indicating that the PtCoNi ternary alloy catalyst prepared by this method has excellent stability.

[0081] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A method for preparing a carbon-supported platinum-based ternary alloy catalyst, characterized in that, Includes the following steps: S1. Disperse the carbon support, platinum-containing compound solution, and soluble metal salt solutions of cobalt and nickel into ethylene glycol to obtain a ternary precursor suspension. S2. A precipitant was added to the ternary precursor suspension and stirred. The mixture was then reacted in a microwave reactor. The product was then separated, washed, and dried to obtain a carbon-supported platinum-based ternary alloy catalyst.

2. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S1, the carbon support is XC-72R or EC300J.

3. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S1, the platinum-containing compound used is chloroplatinic acid.

4. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S1, the soluble metal salts of cobalt and nickel used are nitrates or hydrochlorides.

5. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S1, the ratio of carbon support, platinum-containing compound, soluble cobalt metal salt, and soluble nickel metal salt is (40–80) mg: (0.05–0.11) mmol: (0.01–0.022) mmol: (0.05–0.11) mmol.

6. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S2, the precipitant is potassium hydroxide or sodium hydroxide, and its addition amount satisfies the pH value of the solution system being 11.5 to 12.

5.

7. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, In S2, the microwave reaction conditions are: power of 80-800W and time of 0.5-30min.

8. The method for preparing a carbon-supported platinum-based ternary alloy catalyst according to claim 1, characterized in that, The specific process of separating the product and washing and drying is as follows: After the reaction is complete, let it stand and cool for 30 minutes, then separate the reaction product, add it to a 0.01-0.5 mol / L perchloric acid solution, let it stand for 30-60 minutes, separate it again, and dry it under vacuum.

9. A carbon-supported platinum-based ternary alloy catalyst, prepared by the preparation method according to any one of claims 1-8, characterized in that, In the carbon-supported platinum-based ternary alloy catalyst, the alloy particles are supported on the edge of the carbon support, with an average particle size of 2-3 nm.

10. The application of the carbon-supported platinum-based ternary alloy catalyst as described in claim 9 in the oxygen reduction reaction.

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