A palladium-based alloy catalyst, a method for preparing the same, and use thereof in a formic acid fuel cell

Abstract

This invention discloses a palladium-based alloy catalyst, its preparation method, and its application in formic acid fuel cells, belonging to the field of palladium catalyst electrocatalysis technology. The catalyst prepared by this invention is a ruthenium-doped two-dimensional palladium-based alloy catalyst, which has an ordered mesoporous two-dimensional nanosheet structure. In the preparation process, dodecyltriruthenium is selected as the ruthenium source. Under heating conditions, it decomposes to form CO, which acts as a structure directing agent, inducing the formation of two-dimensional nanosheets and effectively inhibiting the aggregation of metal atoms. During this process, the interaction between palladium and ruthenium metal atoms leads to the formation of ordered mesopores in the catalyst. The surface morphology of the catalyst can be flexibly controlled by controlling the amount of ruthenium metal atoms incorporated. The obtained catalyst exhibits excellent formic acid oxidation performance.

Description

Technical Field

[0001] This invention belongs to the field of palladium catalyst electrocatalysis technology, specifically relating to a palladium-based alloy catalyst, its preparation method, and its application in formic acid fuel cells. Background Technology

[0002] Formic acid fuel cells represent the core application of the formic acid electro-oxidation reaction (FAOR). Compared to methanol fuel cells, they offer higher safety and more convenient storage and transportation. Furthermore, formic acid fuel cells boast a significantly higher energy density than other types of fuel cells, making them highly promising for the new energy sector. In the working system of a formic acid fuel cell, formic acid, as fuel, undergoes an oxidation reaction at the anode, releasing electrons. These electrons are then transferred to the cathode via an external circuit, where they undergo a reduction reaction with oxygen, resulting in a continuous output of electrical energy. However, the electrocatalytic oxidation of formic acid produces CO intermediates. These intermediates have extremely strong adsorption capabilities, preferentially occupying the active sites of the catalyst and hindering effective contact between other reactant molecules and these sites. This ultimately leads to a decrease in catalytic activity and catalyst poisoning, which is a key bottleneck restricting the performance improvement of formic acid fuel cells.

[0003] Palladium exhibits high catalytic activity for the electrocatalytic oxidation of formic acid, making it an ideal FAOR electrocatalyst. Two-dimensional palladium-based catalysts demonstrate even more significant structural advantages in formic acid oxidation. To achieve industrial applications, further performance optimization of two-dimensional palladium-based catalysts is possible. Common optimization strategies include surface modification, alloying, and precise structural control. Alloying can synergistically optimize catalytic performance from multiple dimensions. The introduction of other metal atoms can precisely adjust the d-band center position of palladium, and the adsorption energy of key intermediates can be optimized through electronic reconstruction effects, significantly improving the reactivity of two-dimensional palladium-based catalysts for formic acid oxidation, enhancing structural stability, and extending recycling efficiency. However, the synthesis of two-dimensional palladium-based catalysts still faces multiple challenges, including poor compositional uniformity, insufficient morphological and dimensional uniformity, and low precision in microscopic electronic structure control. Precise structural control can be used to prepare wrinkled, porous, or heterogeneous two-dimensional palladium-based catalysts, increasing the specific surface area and constructing channels conducive to reactant diffusion and product desorption. Summary of the Invention

[0004] This invention provides a palladium-based alloy catalyst, its preparation method, and its application in formic acid fuel cells. The surface morphology of the PdRu alloy catalyst can be flexibly controlled, and the prepared catalyst exhibits good formic acid oxidation performance in formic acid fuel cells.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A palladium-based alloy catalyst, which is a ruthenium-doped two-dimensional palladium-based alloy catalyst, wherein the catalyst is a two-dimensional nanosheet structure with an thickness of 3 to 4 palladium atoms and containing ordered mesopores.

[0006] The catalyst surface has regular channels.

[0007] A method for preparing a palladium-based alloy catalyst includes the following steps: Weigh out the palladium source, dodecacarbonyltriruthenium, and ascorbic acid respectively; The weighed medicine is added to a sealed reaction tube containing oleylamine, and the sealed reaction tube is ultrasonically treated to make the medicine in the reaction tube more evenly dispersed. Place the ultrasonically treated sealed reaction tube in a preheated oil bath, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirring to carry out a constant temperature reaction. After the reaction was completed, the product was centrifuged, washed and dried to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0008] In the steps described above, the palladium source is palladium acetylacetone, palladium trifluoroacetylacetone, bis(benzoylacetone)palladium, bis(cyclopentadiene)palladium, or a carbonyl palladium complex (Pd(CO)2Cl2); the palladium source is selected based on the required amount of palladium. When the palladium source is palladium acetylacetonate, the mass ratio of palladium acetylacetonate, ruthenium dodecylcarbonyl, and ascorbic acid is 1:(0.7-2.1):3; The isothermal reaction is carried out at a temperature of 60~100℃ for 10~14h. The centrifugation speed was 10,000 rpm, and the centrifugation time was 10 min. The washing process was carried out using a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2. An ordered mesoporous two-dimensional PdRu alloy catalyst was obtained by drying in an oven at 60°C for 12 hours.

[0009] The catalyst prepared above can be used for the oxidation of formic acid in formic acid fuel cells.

[0010] Beneficial effects: This invention provides a palladium-based alloy catalyst, its preparation method, and its application in formic acid fuel cells, which has the following advantages compared with the prior art: 1. Ruthenium dodecylcarbonyl is selected to decompose under heating conditions to form CO. CO acts as a structure directing agent, inducing the formation of two-dimensional nanosheets and effectively inhibiting the aggregation of metal atoms. Ascorbic acid is selected as a reducing agent to achieve mild bimetallic co-reduction, ensuring uniform alloying. It also acts as a two-dimensional morphology guide, inhibiting the longitudinal growth of the catalyst and promoting the lateral growth of two-dimensional palladium nanosheets. Oleylamine is selected as a solvent to dissolve the metal precursor, avoiding the hydrolysis or precipitation of metal ions in the aqueous system and providing a homogeneous reaction environment for bimetallic co-reduction. 2. During the preparation process, the interaction between palladium and ruthenium metal atoms leads to the formation of ordered mesopores in the catalyst. This invention can flexibly control the surface morphology of the catalyst by controlling the amount of ruthenium metal atoms incorporated. 3. The method of the present invention has significant advantages for synthesizing ordered mesoporous two-dimensional PdRu alloy catalysts. The ordered mesopores in the prepared ordered mesoporous two-dimensional PdRu alloy catalyst can accelerate the mass transfer kinetics in the formic acid oxidation process and reduce the interfacial mass transfer resistance. Furthermore, its mesoporous structure can significantly increase the specific surface area of ​​the two-dimensional nanostructure, allowing the active sites of the catalyst to be fully exposed. With its unique physical properties of mesoporous structure and regular surface channels, it exhibits advantages such as high activity, resistance to CO poisoning, and long-term cycle stability in the formic acid oxidation reaction. Attached Figure Description

[0011] Figure 1 The ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 1 of this invention is shown in (a) TEM, (b) XRD, and (c) XPS. Figure 2 These are (a) TEM, (b) XRD, and (c) XPS images of the ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 2 of this invention. Figure 3 These are (a) TEM, (b) elemental distribution, (c) XRD, and (d) XPS images of the ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 3 of this invention. Figure 4 The ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 4 of this invention is shown in (a) TEM, (b) XRD, and (c) XPS. Figure 5 The ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 5 of this invention is shown in (a) TEM, (b) XRD, and (c) XPS. Figure 6 The images show the CV curves of the ordered mesoporous two-dimensional PdRu alloy catalyst in (a) 0.5M H2SO4 and (b) 0.5M H2SO4+0.5M HCOOH in the embodiments of the present invention. Figure 7This is the stability test curve of the ordered mesoporous two-dimensional PdRu alloy catalyst in 0.5 M H2SO4 + 0.5 M HCOOH in the embodiments of the present invention. Detailed Implementation

[0012] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments: Example 1

[0013] A method for preparing a palladium-based alloy catalyst includes the following steps: (1) Weigh out 10 mg of palladium acetylacetone, 7 mg of ruthenium dodecylcarbonyl, and 30 mg of ascorbic acid respectively; (2) Add the weighed medicine to sealed reaction tubes containing 5 ml of oleylamine. Place the sealed reaction tubes in an ultrasonic instrument for ultrasonic treatment for 1 hour; (3) Place the ultrasonically sealed reaction tube directly into an oil bath preheated to 80°C, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirrer; (4) Keep the oil bath temperature at 80℃ and react at a constant temperature for 12h. After cooling to room temperature, centrifuge the obtained product, wash it with a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2, and dry it in an oven at 60℃ for 12h to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0014] The catalyst prepared above is a ruthenium-doped one-dimensional palladium-based alloy catalyst. For example... Figure 1 As shown in (a), due to the low amount of dodecyltriruthenium added, the amount of CO produced by its thermal decomposition is reduced, and the CO content is insufficient to form a two-dimensional structure and cause the metal atoms to aggregate into nanoparticles. XRD is shown below. Figure 1 As shown in (b), the diffraction peak of palladium at 2θ = 39.171° belongs to the PdRu alloy. Furthermore, compared to the standard palladium card (JCPDS: 05-0681), the diffraction peak of palladium after doping with ruthenium shifts to a lower angle. This is mainly because ruthenium doping into the palladium lattice causes lattice expansion. XPS as... Figure 1 As shown in (c), Pd 0 3D 5 / 2 and Pd 0 3D 3 / 2 The characteristic peaks all shifted positively, indicating that the d-band center of palladium shifted downward, which is beneficial to improving catalyst performance and accelerating the reaction process. Example 2

[0015] A method for preparing a palladium-based alloy catalyst includes the following steps: (1) Weigh out 10 mg of palladium acetylacetone, 10.5 mg of ruthenium dodecylcarbonyl and 30 mg of ascorbic acid respectively; (2) Add the weighed medicine to a sealed reaction tube containing 5 ml of oleylamine. Place the sealed reaction tube in an ultrasonic instrument for ultrasonic treatment for 1 hour.

[0016] (3) Place the ultrasonically sealed reaction tube directly into an oil bath preheated to 80°C, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirring.

[0017] (4) Maintain the oil bath temperature at 80℃ and react at a constant temperature for 12 h. After cooling to room temperature, centrifuge the obtained product, wash it with a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2, and dry it in an oven at 60℃ for 12 h to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0018] The catalyst prepared above is a ruthenium-doped two-dimensional palladium-based alloy catalyst, which does not contain an ordered mesoporous two-dimensional nanosheet structure. For example... Figure 2 (a) The TEM image shows a two-dimensional nanosheet morphology. Due to the low ruthenium atom content, the reduction kinetics of palladium cannot be effectively controlled. Palladium ions are reduced at their inherent rate, resulting in a flat two-dimensional nanosheet structure without regularly arranged channels on the surface. XRD is shown below. Figure 2 As shown in (b), the diffraction peak of palladium at 2θ = 39.287° belongs to the PdRu alloy. Furthermore, compared to the standard palladium card (JCPDS: 05-0681), the diffraction peak of palladium after doping with ruthenium shifts to a lower angle. This is mainly because ruthenium doping into the palladium lattice causes lattice expansion. XPS as... Figure 2 As shown in (c), Pd 0 3D 5 / 2 and Pd 0 3D 3 / 2 The characteristic peaks all shifted positively, indicating that the d-band center of palladium shifted downward, which is beneficial to improving catalyst performance and accelerating the reaction process. Example 3

[0019] A method for preparing a palladium-based alloy catalyst includes the following steps: (1) Weigh out 10 mg of palladium acetylacetonate, 14 mg of ruthenium dodecyl carbonyl and 30 mg of ascorbic acid respectively.

[0020] (2) Add the weighed medicine to a sealed reaction tube containing 5 ml of oleylamine. Place the sealed reaction tube in an ultrasonic instrument for ultrasonic treatment for 1 hour.

[0021] (3) Place the ultrasonically sealed reaction tube directly into an oil bath preheated to 80°C, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirring.

[0022] (4) Maintain the oil bath temperature at 80℃ and react at a constant temperature for 12 h. After cooling to room temperature, centrifuge the obtained product, wash it with a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2, and dry it in an oven at 60℃ for 12 h to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0023] The catalyst prepared above is a ruthenium-doped two-dimensional palladium-based alloy catalyst, which contains an ordered mesoporous two-dimensional nanosheet structure. For example... Figure 3 (a) shows a TEM that forms a uniform two-dimensional nanosheet morphology, and its surface has clearly and regularly arranged channels. Figure 3 The elemental distribution diagram in (b) shows that palladium and ruthenium are evenly distributed. At this point, the amount of ruthenium precursor added can precisely adjust the coordination environment and reduction barrier of the bimetallic ions, allowing palladium and ruthenium ions to nucleate synchronously and grow uniformly. XRD pattern as shown... Figure 3 As shown in (c), the diffraction peak of palladium at 2θ = 39.217° belongs to the PdRu alloy. Furthermore, compared to the standard palladium card (JCPDS: 05-0681), the diffraction peak of palladium after doping with ruthenium shifts to a lower angle. This is mainly because ruthenium doping into the palladium lattice causes lattice expansion. XPS as... Figure 3 As shown in (d), Pd 0 3D 5 / 2 and Pd 0 3D 3 / 2 The characteristic peaks all shifted positively, indicating that the d-band center of palladium shifted downward, which is beneficial to improving catalyst performance and accelerating the reaction process. Example 4

[0024] A method for preparing a palladium-based alloy catalyst includes the following steps: (1) Weigh out 10 mg of palladium acetylacetone, 17.5 mg of ruthenium dodecylcarbonyl and 30 mg of ascorbic acid respectively.

[0025] (2) Add the weighed medicine to a sealed reaction tube containing 5 ml of oleylamine. Place the sealed reaction tube in an ultrasonic instrument for ultrasonic treatment for 1 hour.

[0026] (3) Place the ultrasonically sealed reaction tube directly into an oil bath preheated to 80°C, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirring.

[0027] (4) Maintain the oil bath temperature at 80℃ and react at a constant temperature for 12 h. After cooling to room temperature, centrifuge the obtained product, wash it with a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2, and dry it in an oven at 60℃ for 12 h to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0028] The catalyst prepared above is a ruthenium-doped two-dimensional palladium-based alloy catalyst, which does not contain an ordered mesoporous two-dimensional nanosheet structure. For example... Figure 4 (a) The TEM image shows a two-dimensional nanosheet morphology. However, because ruthenium ions are more easily reduced, the increased concentration of ruthenium ions leads to a significantly faster reduction rate than palladium ions. Ruthenium atoms rapidly precipitate and aggregate. The rapid growth of ruthenium atoms drives the lateral contraction of the nanosheets, inhibiting the directional formation of channels. Therefore, there are no regularly arranged channels on its surface. XRD is shown below. Figure 4 As shown in (b), the diffraction peak of palladium at 2θ = 39.416° belongs to the PdRu alloy. Furthermore, compared to the standard palladium card (JCPDS: 05-0681), the diffraction peak of palladium after doping with ruthenium shifts to a lower angle. This is mainly because ruthenium doping into the palladium lattice causes lattice expansion. XPS as... Figure 4 As shown in (c), Pd 0 3D 5 / 2 and Pd 0 3D 3 / 2 The characteristic peaks all shifted positively, indicating that the d-band center of palladium shifted downward, which is beneficial to improving catalyst performance and accelerating the reaction process. Example 5

[0029] A method for preparing a palladium-based alloy catalyst includes the following steps: (1) Weigh out 10 mg of palladium acetylacetonate, 21 mg of ruthenium dodecyl carbonyl and 30 mg of ascorbic acid respectively.

[0030] (2) Add the weighed medicine to a sealed reaction tube containing 5 ml of oleylamine. Place the sealed reaction tube in an ultrasonic instrument for ultrasonic treatment for 1 hour.

[0031] (3) Place the ultrasonically sealed reaction tube directly into an oil bath preheated to 80°C, ensuring that the liquid in the reaction tube is completely submerged below the surface of the oil bath, and turn on the magnetic stirring.

[0032] (4) Maintain the oil bath temperature at 80℃ and react at a constant temperature for 12 h. After cooling to room temperature, centrifuge the obtained product, wash it with a mixed solution of cyclohexane and ethanol in a volume ratio of 1:2, and dry it in an oven at 60℃ for 12 h to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

[0033] The catalyst prepared above is a ruthenium-doped two-dimensional palladium-based alloy catalyst, which does not contain an ordered mesoporous two-dimensional nanosheet structure. For example... Figure 5 (a) shows a TEM image that depicts a two-dimensional nanosheet morphology, but its surface lacks regularly arranged channels. XRD is shown below. Figure 5As shown in (b), the diffraction peak of palladium at 2θ = 39.73146° belongs to the PdRu alloy. Furthermore, compared to the standard palladium card (JCPDS: 05-0681), the diffraction peak of palladium after doping with ruthenium shifts to a lower angle. This is mainly because ruthenium doping into the palladium lattice causes lattice expansion. XPS as... Figure 5 As shown in (c), Pd 0 3D 5 / 2 and Pd 0 3D 3 / 2 The characteristic peaks all shifted positively, indicating that the d-band center of palladium shifted downward, which is beneficial to improving catalyst performance and accelerating the reaction process.

[0034] Performance testing: The FAOR electrocatalytic performance of the ordered mesoporous two-dimensional PdRu alloy catalyst prepared in Example 3 was tested. The test method included the following steps: The testing instrument was a CHI660 electrochemical workstation, using a three-electrode system. A carbon rod was used as the counter electrode, and an Ag / AgCl electrode as the reference electrode. The prepared ordered mesoporous two-dimensional PdRu alloy catalyst was used as the working electrode. The working electrode was prepared by dispersing 3 mg of catalyst and 5 μL of Nafion solution (5 wt%) in a mixed solution of 375 μL of water and 125 μL of isopropanol, followed by sonication for 1 h to obtain a homogeneous solution. Then, 4.27 μL of catalyst ink slurry was uniformly drop-coated onto a 3 mm diameter L-shaped glassy carbon electrode and allowed to air dry. Electrocatalytic FAOR testing was conducted at room temperature and atmospheric pressure. First, its mass activity was tested using a 0.5 M H2SO4 solution. Before testing, the H2SO4 electrolyte was purged with high-purity nitrogen for 30 min. The potential range was -0.2 to 1.0 V, and the scan rate was 50 mV s. -1 ,pass Figure 6 As shown in the CV curve in (a), Example 3 exhibits the highest specific activity compared to commercial 10% Pd / C. Peak current density was then measured in a mixed solution of 0.5 M H₂SO₄ and 0.5 M HCOOH. High-purity nitrogen was purged for 30 min before the test. The potential range was -0.2 to 1.0 V, and the scan rate was 50 mV s. -1 ,pass Figure 6 As can be seen from the CV curve in (b), Example 3 has the highest peak current density; Figure 7 For the stability test of Example 3 and commercial 10% Pd / C, after a stability test of 3600s, Example 3 still maintained high activity. The above results show that the ordered mesoporous two-dimensional PdRu alloy catalyst synthesized in Example 3 has ordered mesopores that are beneficial to charge transfer in the electrocatalytic test of formic acid oxidation and can accelerate the reaction.

[0035] As can be seen from the above embodiments, the advantage of the ordered mesoporous two-dimensional PdRu alloy catalyst for formic acid oxidation in fuel cells and its preparation method is that the dodecyltriruthenium is selected because the drug decomposes under heating conditions to form CO. CO acts as a structure directing agent, inducing the generation of two-dimensional nanosheets and effectively inhibiting the aggregation of metal atoms. In this process, the interaction between palladium and ruthenium atoms leads to the formation of ordered mesopores in the catalyst. When the ruthenium atom content is too low, the ruthenium atoms are sparsely dispersed in the palladium matrix, which cannot effectively regulate the reduction kinetics of palladium. Palladium ions are still reduced at their inherent rate, forming a flat two-dimensional sheet structure. When the ruthenium atom content is too high, because ruthenium ions are more easily reduced, the increased concentration of ruthenium ions leads to a significantly faster reduction rate than palladium ions. Ruthenium atoms precipitate and aggregate rapidly. The rapid growth of ruthenium atoms drives the lateral contraction of the nanosheets, inhibiting the directional formation of channels. Therefore, there are no regularly arranged channels on its surface. When the ruthenium atom content is at a critical value, the amount of ruthenium ions added can precisely regulate the coordination environment and reduction barrier of the bimetallic ions. Therefore, the surface morphology of the catalyst can be flexibly controlled by controlling the amount of ruthenium metal atoms incorporated. The ordered mesoporous two-dimensional PdRu alloy catalyst exhibits ordered mesopores that accelerate mass transfer kinetics and reduce interfacial mass transfer resistance during formic acid oxidation. Furthermore, its mesoporous structure significantly increases the specific surface area of ​​the two-dimensional nanostructure, fully exposing the catalyst's active sites. Leveraging its unique physical properties of mesoporous structure and regularly oriented channels, it demonstrates high activity, resistance to CO poisoning, and long-term cycling stability in the formic acid oxidation reaction. The method of this invention offers significant advantages for the synthesis of ordered mesoporous two-dimensional PdRu alloy catalysts.

[0036] The above description is only a preferred embodiment of the present invention. It should be noted that those skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be considered within the scope of protection of the present invention.

Claims

1. A palladium-based alloy catalyst, characterized in that, The catalyst is a ruthenium-doped two-dimensional palladium-based alloy catalyst, and the catalyst has an ordered mesoporous two-dimensional nanosheet structure.

2. The palladium-based alloy catalyst according to claim 1, characterized in that, The catalyst surface has regular channels.

3. The palladium-based alloy catalyst according to claim 1 or 2, characterized in that, The catalyst is 3 to 4 palladium atoms thick.

4. A method for preparing a palladium-based alloy catalyst, characterized in that, Includes the following steps: Weigh out the palladium source, dodecacarbonyltriruthenium, and ascorbic acid respectively; Add the weighed medicine to the oleamide, seal and sonicate to make the medicine more evenly dispersed. After ultrasonic treatment, a stirring and constant-temperature reaction is carried out. After the reaction was completed, the product was centrifuged, washed and dried to obtain an ordered mesoporous two-dimensional PdRu alloy catalyst.

5. The method for preparing the palladium-based alloy catalyst according to claim 4, characterized in that, The surface morphology of the catalyst can be controlled by adjusting the amount of ruthenium metal atoms incorporated.

6. The method for preparing the palladium-based alloy catalyst according to claim 4, characterized in that, The palladium source is palladium acetylacetone, palladium trifluoroacetylacetone, bis(benzoylacetone)palladium, bis(cyclopentadiene)palladium, or a carbonyl palladium complex.

7. The method for preparing the palladium-based alloy catalyst according to claim 4 or 6, characterized in that, When the palladium source is palladium acetylacetonate, the mass ratio of palladium acetylacetonate, ruthenium dodecylcarbonyl, and ascorbic acid is 1:(0.7-2.1):

3.

8. The method for preparing the palladium-based alloy catalyst according to claim 4, characterized in that, The constant temperature reaction is 60~100℃ and the time is 10~14h.

9. The method for preparing the palladium-based alloy catalyst according to claim 4, characterized in that, The centrifugation speed was 10,000 rpm, and the time was 10 minutes.

10. The application of the palladium-based alloy catalyst according to claims 1-3, characterized in that, The catalyst is used for the oxidation of formic acid in formic acid fuel cells.

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