CO poisoning resistant PtRu electrocatalyst for fuel cell and preparation method of CO poisoning resistant PtRu electrocatalyst

Abstract

The invention relates to the technical field of fuel cells, and mainly relates to a CO poisoning resistant PtRu electrocatalyst for a fuel cell and a preparation method of the CO poisoning resistant PtRu electrocatalyst. The preparation method comprises the following steps: uniformly mixing a platinum-ruthenium nanoparticle suspension and a carbon powder suspension, and then separating out a solid to obtain a catalyst precursor; and annealing the catalyst precursor in a reducing atmosphere, and cooling to obtain the CO poisoning resistant PtRu electrocatalyst for the fuel cell. The platinum-ruthenium nanoparticles are directly loaded on the carbon material, the loading process is simple and easy to operate, the effect is obvious, the particles are uniformly distributed, and no obvious atom agglomeration phenomenon occurs. And the prepared catalyst has the characteristics of good HOR catalytic effect, high stability, strong CO toxicity resistance and capability of being prepared on a large scale, and has great positive significance in actual fuel cell application.

Description

Technical Field

[0001] This application relates to the technical field of fuel cells, and mainly relates to a PtRu electrocatalyst resistant to CO poisoning for fuel cells and a preparation method thereof. Background Art

[0002] In energy storage and conversion devices, fuel cells, as an important electrochemical energy conversion technology, can directly and efficiently convert the chemical energy stored in fuels into electrical energy, and have broad application prospects. Fuel cells use solid ion exchange membranes to conduct hydroxide ions (OH⁻) or protons (H + ) in the solid membrane, with high safety. Fuel cells have the advantages of high specific power and specific energy, environmental friendliness, no electrolyte loss, and fast load response, and have great application potential in portable power sources and vehicle power sources.

[0003] Fuel cells undergo a hydrogen oxidation reaction (HOR) at the anode and an oxygen reduction reaction (ORR) at the cathode. The HOR reaction occurring at the anode uses hydrogen as an energy source. However, the oxidation reaction rate of hydrogen is relatively low, and a catalyst is required to accelerate the reaction rate. The hydrogen sources for fuel cells are diverse. For example, hydrogen produced by electrolyzing water has high purity, but the cost of electrolyzing water to produce hydrogen is relatively high; more commonly used is gray hydrogen produced by industrial production, but its purity is not high, and it contains other gases such as carbon monoxide (CO) produced by industrial production. The commonly used Pt catalysts or Pt-based alloy catalysts in fuel cells are more susceptible to the influence of CO in the hydrogen source, resulting in catalyst poisoning and loss of catalytic performance. This is mainly because CO shows a strong adsorption tendency on the surface of platinum group metals (PGM), and the active sites of the catalyst are easily occupied by CO, leading to catalyst poisoning. Even when the CO content reaches only 10 μmol / mol, it will seriously affect the HOR performance of the Pt catalyst. To weaken the adsorption of CO on the Pt surface, the surface of the catalyst can be affected by regulating the composition and morphology. For example, adding transition elements to the Pt catalyst can adjust the d-band center of the catalyst, thereby weakening the CO adsorption ability. Currently, the research on CO-resistant catalysts is relatively extensive, but the existing technologies still have the following deficiencies: (1) During the synthesis process of platinum-based alloy catalysts, the nanoparticles are prone to agglomeration at high temperatures, resulting in low utilization rate of surface atoms, directly affecting the CO-resistant activity of the catalyst. (2) Platinum and transition elements are prone to phase separation when forming alloys, and there will be Pt-rich regions and transition element-rich regions in the particles, making it difficult to form alloys and affecting the synergistic effect between them. (3) Usually, the synthesis methods of platinum-based alloy catalysts are relatively complex and difficult to scale up for large-scale preparation.

[0004] Despite the significant efforts dedicated to developing fuel cell anode catalysts with high CO tolerance, there are still major challenges regarding the solubility, stability, and anti-poisoning ability of these catalysts under the influence of CO. Therefore, there is a need for improvement and development in the existing technology. Summary of the Invention

[0005] In view of the deficiencies of the above-mentioned prior art, the purpose of this application is to provide a CO-resistant PtRu electrocatalyst for fuel cells and its preparation method, aiming to solve the problem that existing catalysts are easily poisoned by CO in the hydrogen source.

[0006] The technical solution of this application is as follows: In the first aspect, this application provides a preparation method for a CO-resistant PtRu electrocatalyst for fuel cells, which includes the following steps: Mix the platinum-ruthenium nanoparticle suspension and the carbon powder suspension evenly, and then separate the solid to obtain the catalyst precursor; Anneal the catalyst precursor in a reducing atmosphere and then cool it to obtain the CO-resistant PtRu electrocatalyst for fuel cells.

[0007] In this application, platinum-ruthenium nanoparticles are loaded on carbon materials. The loading process is simple and easy to operate, with obvious effects, uniform particle distribution, and not easy to agglomerate. Moreover, the addition of Ru weakens the adsorption and desorption of Pt to CO, starts to oxidize at low potentials, and the CO adsorbed on the surface is more easily oxidized, so it has excellent anti-CO poisoning performance.

[0008] Further, the platinum-ruthenium nanoparticle suspension is prepared by dispersing platinum-ruthenium nanoparticles in an organic solvent; the carbon powder suspension is prepared by dispersing carbon powder in an organic solvent; The organic solvent is chloroform.

[0009] Further, the platinum-ruthenium nanoparticle suspension and the carbon powder suspension are mixed according to the mass ratio of platinum-ruthenium nanoparticles to carbon powder of 0.4 - 0.8:1.

[0010] Further, the annealing temperature is 200 - 800 °C, and the heat preservation time is 0.1 - 10 h.

[0011] Further, every 250 mg of the platinum-ruthenium nanoparticles are dispersed in 10 - 1000 mL of an organic solvent; The preparation method of the platinum-ruthenium nanoparticles includes the following steps: Add the platinum precursor and the ruthenium precursor to a mixed solution composed of oleylamine, diphenyl ether, and o-diphenyl ether, then add 1,2-bis(decylthio)ethane, and heat and react completely under an inert atmosphere. After cooling, centrifuge to obtain the solid.

[0012] Further, the platinum precursor is platinum acetylacetonate, and the ruthenium precursor is ruthenium acetylacetonate; The molar ratio of the platinum precursor to the ruthenium precursor is 1-3:1-10; For every 0.1-3 g of the platinum precursor, 10-30 mL of oleylamine, 80-120 mL of diphenyl ether, 5-15 mL of o-diphenyl ether, and 0.6-0.7 g of 1,2-didecylene glycol are used.

[0013] Further, the inert atmosphere is argon; The heating temperature is 200-300 °C, and the time is 5-100 min; The centrifugation is carried out by placing the mixture obtained after the reaction in a centrifuge tube of a centrifuge, adding 5 g of absolute ethanol to every 1 g of the mixture, centrifuging at 8000-12000 rpm for 10-20 min, and then pouring off the supernatant.

[0014] Further, every 250 mg of carbon powder is dispersed in 10-1000 mL of an organic solvent; The carbon powder is obtained by calcining the carbon material in air at 185 °C for 4 h and then grinding; The carbon material is one or more of Vulcan XC72, KB300, KB600, BP2000, Toray carbon, and amorphous carbon.

[0015] Further, the separation of the solid is carried out by suction filtration and drying with n-hexane; The reducing atmosphere is an argon-hydrogen atmosphere, and the volume fraction of hydrogen in the argon-hydrogen atmosphere is 5-30%.

[0016] In a second aspect, the present application provides a CO-resistant PtRu electrocatalyst for a fuel cell, which is prepared by the preparation method of the CO-resistant PtRu electrocatalyst for a fuel cell as described in the first aspect.

[0017] Beneficial effects: The platinum-ruthenium particles prepared in the present application have nano-scale catalysts. Due to the small average particle size and uniform dispersion of the prepared platinum-ruthenium nanoparticles, they have good HOR catalytic effect, high stability, excellent CO poisoning resistance, and can be produced in large quantities. Then, the platinum-ruthenium nanoparticles are directly loaded on the carbon material, and the loading process is very simple and easy to operate, with obvious effects, uniform particle distribution, and no obvious atomic agglomeration phenomenon. Due to the small average particle size and uniform dispersion of the prepared platinum-ruthenium nanoparticles, they have good HOR catalytic effect, high stability, strong CO poisoning resistance, and can be prepared in large quantities, which has great positive significance in the actual application of fuel cells. Description of the Drawings

[0018] Figure 1TEM image of the PtRu-0 electrocatalyst prepared in Example 1 of this application.

[0019] Figure 2 XRD pattern of the PtRu-0 electrocatalyst prepared in Example 1 of this application.

[0020] Figure 3 Comparison chart of HOR polarization curves of the catalysts of Comparative Example 1 and Example 1 of this application.

[0021] Figure 4 Comparison chart of anti-CO poisoning curves of the catalysts of Comparative Example 1 and Example 1 of this application.

[0022] Figure 5 TEM image of the PtRu-1 electrocatalyst prepared in Example 2 of this application.

[0023] Figure 6 XRD pattern of the PtRu-1 electrocatalyst prepared in Example 2 of this application.

[0024] Figure 7 Comparison chart of HOR polarization curves of the catalysts of Comparative Example 1 and Example 2 of this application.

[0025] Figure 8 Comparison chart of anti-CO poisoning curves of the catalysts of Comparative Example 1 and Example 2 of this application.

[0026] Figure 9 TEM image of the PtRu-2 electrocatalyst prepared in Example 3 of this application.

[0027] Figure 10 XRD pattern of the PtRu-2 electrocatalyst prepared in Example 3 of this application.

[0028] Figure 11 Comparison chart of HOR polarization curves of the catalysts of Comparative Example 1 and Example 3 of this application.

[0029] Figure 12 Comparison chart of anti-CO poisoning curves of the catalysts of Comparative Example 1 and Example 3 of this application. Detailed implementation manners

[0030] This application provides a CO-resistant PtRu electrocatalyst for fuel cells and its preparation method. To make the purpose, technical solution and effects of this application clearer and more definite, the following further details this application. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0031] This application provides a preparation method for a CO-resistant PtRu electrocatalyst for fuel cells, which includes the following steps: S1. Mix the platinum-ruthenium nanoparticle suspension and the carbon powder suspension evenly, and then separate the solid to obtain the catalyst precursor. S2. Anneal the catalyst precursor under a reducing atmosphere and then cool it to obtain the CO-resistant PtRu electrocatalyst for fuel cells.

[0032] In this application, platinum-ruthenium nanoparticles are loaded on the carbon material. The loading process is simple and easy to operate, with obvious effects, uniform particle distribution, and not easy to agglomerate. Moreover, the addition of Ru weakens the adsorption and desorption of CO by Pt, starts to oxidize at low potentials, and the CO adsorbed on the surface is more easily oxidized, so it has excellent CO poisoning resistance.

[0033] Further, the platinum-ruthenium nanoparticle suspension is prepared by dispersing platinum-ruthenium nanoparticles in an organic solvent; the carbon powder suspension is prepared by dispersing carbon powder in an organic solvent. Among them, the organic solvent is chloroform.

[0034] Further, every 250 mg of platinum-ruthenium nanoparticles are dispersed in 10 - 1000 mL of organic solvent, and specifically, they can be dispersed evenly by ultrasonic treatment for 20 - 30 min.

[0035] Further, the preparation method of the platinum-ruthenium nanoparticles includes the following steps: S0. Add the platinum precursor and the ruthenium precursor to a mixed solution composed of oleylamine, diphenyl ether, and o-diphenyl ether, then add 1,2-bis(decylthio)ethane, and heat and react completely under an inert atmosphere. After cooling, centrifuge to obtain the solid platinum-ruthenium nanoparticles.

[0036] Further, in step S0, the platinum precursor is platinum acetylacetonate, and the ruthenium precursor is ruthenium acetylacetonate. The molar ratio of the platinum precursor to the ruthenium precursor is 1 - 3:1 - 10. For every 0.1 - 3 g of the platinum precursor, 10 - 30 mL of oleylamine, 80 - 120 mL of diphenyl ether, 5 - 15 mL of o-diphenyl ether, and 0.6 - 0.7 g of 1,2-bis(decylthio)ethane are used.

[0037] This application prepares platinum-ruthenium nanoparticles by the sol-gel method, and by optimizing the alloy structure, single atoms or ultra-small clusters of Pt atoms are evenly dispersed in the Ru system, increasing the interface between Pt atoms and Ru atoms, thereby inhibiting the agglomeration of Ru, improving the catalytic utilization rate of Pt and Ru atoms, and improving the catalytic performance and stability for HOR.

[0038] Further, in step S0, the inert atmosphere is argon. Specifically, before the reaction, the air can be discharged by introducing argon for 20 - 30 min, and the reaction is carried out while maintaining the argon reflux state.

[0039] Further, in step S0, the heating temperature is 200 - 300 °C and the time is 5 - 100 min.

[0040] Further, in step S0, the cooling can be carried out by natural cooling; after cooling, the centrifugation can be carried out by placing the mixture obtained after the reaction in a centrifuge tube of a centrifuge, adding 5 g of absolute ethanol to every 1 g of the mixture, centrifuging at 8000 - 12000 rpm for 10 - 20 min, and pouring off the supernatant. The obtained black nanoparticles are platinum - ruthenium nanoparticles.

[0041] In this application, the addition of Ru weakens the adsorption and desorption of CO by Pt, and can start to oxidize at a low potential, making the adsorbed CO on the surface easier to oxidize. Therefore, the prepared catalyst has excellent anti - CO poisoning performance. Due to the small average particle size and uniform dispersion of the prepared platinum - ruthenium nanoparticles, they have good HOR catalytic effect, high stability, excellent anti - CO poisoning performance, and can be produced in large quantities.

[0042] Further, 250 mg of carbon powder is dispersed in 10 - 1000 mL of organic solvent, and it can be specifically dispersed evenly by ultrasonic treatment for 20 - 30 min.

[0043] Further, the carbon powder is obtained by calcining the carbon material at 185 °C for 4 h and then grinding. Among them, the calcined carbon material can be ground until it is evenly dispersed. The carbon material can specifically be one or more of Vulcan XC72, KB300, KB600, BP2000, Toraycarbon, and amorphous carbon.

[0044] In this application, in addition to removing the surfactant on the surface of the carbon material by calcining the carbon material, after calcining, the platinum - ruthenium nanoparticles can be better loaded on the surface of the carbon material. Specifically, if the calcining temperature is too low or the calcining time is too short, the catalyst is not easy to be loaded. If the calcining is excessive, the carbon material will be oxidized, which will instead affect the loading performance of the carbon material.

[0045] Further, in step S1, the platinum - ruthenium nanoparticle suspension and the carbon powder suspension are mixed according to the mass ratio of platinum - ruthenium nanoparticles to carbon powder of 0.4 - 0.8:1.

[0046] In this application, when the mass ratio of platinum to ruthenium in the platinum - ruthenium nanoparticles is controlled at 0.32 - 0.4:1, by controlling the mass ratio of platinum - ruthenium nanoparticles to carbon powder, the platinum loading can be controlled at 7% - 10%, and the ruthenium loading can be controlled at 17% - 20%.

[0047] Further, in step S1, the separation of the solid is carried out by suction filtration and drying with n - hexane.

[0048] Further, in step S2, the reducing atmosphere is an argon-hydrogen atmosphere, and the volume percentage of hydrogen in the argon-hydrogen atmosphere is 5-30%.

[0049] Further, in step S2, the annealing temperature is 200-800 °C, and the heat preservation time is 0.1-10 h. In this application, sintering is carried out by annealing treatment to fix the platinum-ruthenium nanoparticles loaded on the surface of the carbon powder.

[0050] This application directly loads the prepared platinum-ruthenium nanoparticles on the carbon material after air calcination. The loading process is very simple and easy to operate, with obvious effects, uniform particle distribution, and no obvious atomic agglomeration phenomenon.

[0051] This application also provides a fuel cell anti-CO poisoning PtRu electrocatalyst, which is prepared by the preparation method of the fuel cell anti-CO poisoning PtRu electrocatalyst as described above. In this application, the prepared platinum-ruthenium particles are catalysts with nanoscale prepared by the sol-gel method. Due to the small average particle size and uniform dispersion of the prepared platinum-ruthenium nanoparticles, they have the characteristics of good HOR catalytic effect, high stability, strong anti-CO poisoning property, and can be prepared in large quantities, which has great positive significance in the actual application of fuel cells.

[0052] The following is further illustrated by specific examples.

[0053] Comparative Example 1 Take the commercially available platinum-carbon catalyst (40% Pt / C) with a platinum loading of 40% as Comparative Example 1.

[0054] Example 1 The preparation method of the PtRu-0 electrocatalyst in Example 1 includes the following steps: Add 0.12 g of platinum acetylacetonate and 1.2 g of ruthenium acetylacetonate to a three-necked flask containing a mixed solution of 20 mL of oleylamine, 100 mL of diphenyl ether, and 10 mL of o-diphenyl ether. Then add 0.63 g of 1,2-decanediol, introduce argon for 20 min to discharge air, heat to 260 °C under the condition of maintaining argon reflux (argon atmosphere) and react for 30 min. After natural cooling, add 5 g of absolute ethanol to every 1 g of the obtained mixture, and then centrifuge at 10000 rpm for 10 min. The black nanoparticles obtained by pouring off the supernatant are platinum-ruthenium nanoparticles.

[0055] KB600 is heated to 185 °C and then air-calcined for 4 h, and ground until evenly dispersed to obtain carbon powder. Every 250 mg of carbon powder is dispersed in 80 mL of chloroform to obtain a carbon powder suspension.

[0056] A platinum-ruthenium nanoparticle suspension was obtained by dispersing 250 mg of platinum-ruthenium nanoparticles in 80 mL of chloroform. The platinum-ruthenium nanoparticle suspension and the carbon powder suspension were mixed according to the mass ratio of platinum-ruthenium nanoparticles to carbon powder of 0.57:1 and shaken evenly, and then filtered with n-hexane and dried to obtain a catalyst precursor.

[0057] The catalyst precursor was heated to 400 °C in an argon-hydrogen atmosphere (the volume ratio of hydrogen in the argon-hydrogen atmosphere was 5%) and held for 1 h, and then naturally cooled to obtain the PtRu-0 electrocatalyst of Example 1.

[0058] The TEM image of the PtRu-0 electrocatalyst prepared in Example 1 is as Figure 1 shown, and the XRD image is as Figure 2 shown.

[0059] The platinum-carbon catalyst of Comparative Example 1 and the PtRu-0 electrocatalyst prepared in Example 1 were subjected to RED testing. 5 mg of the catalyst was put into 500 μL of ultrapure water and sonicated to make an ink, and the ink was dropped on the surface of the platinum-carbon electrode according to the ratio of 10 μL per square centimeter, and Nafion solution was dropped as an adhesive according to the ratio of 15 μL per square centimeter to make a working electrode. In the electrolytic cell, a 0.1 M KOH solution was used as the electrolyte, a reversible hydrogen was used as the reference electrode, and a platinum wire was used as the counter electrode. Before each test, the electrolyte was purged with argon, and then hydrogen was introduced to reach the saturation state. The working electrode was maintained at 0 V for 2 s to eliminate cation adsorption. The HOR polarization curves of the electrocatalysts of Comparative Example 1 and Example 1 were measured by RDE testing in a 0.1 M KOH solution saturated with H2 at a scan rate of 20 mV / s. The comparison diagram of the measured polarization curves is as Figure 3 (40% Pt / C in the figure is Comparative Example 1, and PtRu-0 is Example 1) shown.

[0060] The platinum-carbon catalyst of Comparative Example 1 and the PtRu-0 electrocatalyst prepared in Example 1 were subjected to anti-CO poisoning testing. Argon was introduced into the electrolytic cell containing a 0.1 M KOH solution for 30 min, and then a reversible hydrogen was prepared in the 0.1 M KOH solution as the reference electrode, and a platinum wire was used as the counter electrode. The above-prepared working electrode was used as a three-electrode system. After the preparation of the reversible hydrogen was completed, the working electrode was activated in a saturated Ar electrolyte at a rate of 50 mV / s between 0.05 V and 0.8 V vs. RHE until a stable CV curve was obtained. After the activation was completed, the background current was measured, and then a CO curve sweep was performed at a rate of 50 mV / s between -0.05 V and 0.8 V vs. RHE at a rotation speed of 900 rpm to obtain a CO sweep curve. The comparison diagram of the CO sweep curves of Comparative Example 1 and Example 1 is as Figure 4 (40% Pt / C in the figure is Comparative Example 1, and PtRu-0 is Example 1) shown.

[0061] Example 2 The preparation method of the PtRu-1 electrocatalyst of Example 2 comprises the following steps: Add 0.12 g of platinum acetylacetonate and 1.20 g of ruthenium acetylacetonate into a three-necked flask containing a mixed solution of 20 mL of oleylamine, 100 mL of diphenyl ether and 10 mL of o-diphenyl ether, then add 0.63 g of 1,2-decanediol, introduce argon for 20 min to expel air, heat to 260 °C under the condition of maintaining argon reflux (argon atmosphere) and react for 30 min. After natural cooling, add 5 g of absolute ethanol to every 1 g of the obtained mixture, then centrifuge at 10000 rpm for 10 min, and pour out the supernatant. The obtained black nanoparticles are platinum-ruthenium nanoparticles.

[0062] Heat KB600 to 185 °C and then burn it in air for 4 h, grind it until it is evenly dispersed to obtain carbon powder, and disperse every 250 mg of carbon powder in 80 mL of chloroform to obtain a carbon powder suspension.

[0063] Disperse every 250 mg of platinum-ruthenium nanoparticles in 80 mL of chloroform to obtain a platinum-ruthenium nanoparticle suspension. Mix the platinum-ruthenium nanoparticle suspension and the carbon powder suspension according to the mass ratio of platinum-ruthenium nanoparticles to carbon powder of 0.57:1, shake evenly, and filter and dry with n-hexane to obtain a catalyst precursor.

[0064] Heat the catalyst precursor to 400 °C in an argon-hydrogen atmosphere (the volume fraction of hydrogen in the argon-hydrogen atmosphere is 5%), keep it warm for 1 h and then cool it naturally, and then heat it to 185 °C in an air atmosphere, keep it warm for 1 h and then cool it naturally to obtain the PtRu-1 electrocatalyst of Example 2.

[0065] The TEM image of the PtRu-1 electrocatalyst prepared in Example 2 is as Figure 5 shown, and the XRD image is as Figure 6 shown.

[0066] Perform RED test on the PtRu-1 electrocatalyst prepared in Example 2. Put 5 mg of the catalyst into 500 μL of ultrapure water and ultrasonically make it into an ink, and drop the ink on the surface of the platinum-carbon electrode according to the proportion of 10 μL per square centimeter, and drop Nafion solution as an adhesive according to the proportion of 15 μL per square centimeter to make a working electrode. Use a 0.1 M KOH solution as the electrolyte in the electrolytic cell, use a reversible hydrogen electrode as the reference electrode, and a platinum wire as the counter electrode. Before each test, purge the electrolyte with argon, and then introduce hydrogen to reach a saturated state. The working electrode is maintained at 0 V for 2 s to eliminate cation adsorption. The HOR polarization curves of the PtRu-1 electrocatalysts of Comparative Example 1 and Example 2 are measured at a scan rate of 20 mV / s in a 0.1 M KOH solution saturated with H2 by RDE test. The comparison diagram of the measured polarization curves is asFigure 7 (In the figure, 40% Pt / C is Comparative Example 1 and PtRu-1 is Example 2).

[0067] The PtRu-1 electrocatalyst prepared in Example 2 was subjected to anti-CO poisoning test. Argon was introduced into the electrolytic cell containing 0.1 M KOH solution for 30 min, and then reversible hydrogen was prepared in 0.1 M KOH solution as the reference electrode, a platinum wire was used as the counter electrode, and the working electrode prepared above was used as the three-electrode system. After the preparation of reversible hydrogen, the working electrode was activated in a saturated Ar electrolyte at a rate of 50 mV / s between 0.05 V and 0.8 V vs. RHE until a stable CV curve was obtained. After the activation, the background current was measured, and then a CO curve sweep was performed at a rate of 50 mV / s between -0.05 V and 0.8 V vs. RHE at a rotation speed of 900 rpm to obtain a CO sweep curve. The comparison chart of the CO sweep curves of Comparative Example 1 and Example 2 is as shown in Figure 8 (In the figure, 40% Pt / C is Comparative Example 1 and PtRu-1 is Example 2).

[0068] Example 3 The preparation method of the PtRu-2 electrocatalyst in Example 3 includes the following steps: 0.12 g of platinum acetylacetonate and 1.2 g of ruthenium acetylacetonate were added to a three-necked flask containing a mixed solution of 20 mL of oleylamine, 100 mL of diphenyl ether and 10 mL of o-diphenyl ether. Then 0.63 g of 1,2-decanediol was added, and argon was introduced for 20 min to expel air. The mixture was heated to 260 °C and reacted for 30 min while maintaining an argon reflux state (argon atmosphere). After natural cooling, 5 g of absolute ethanol was added to each 1 g of the prepared mixture, and then centrifuged at 10000 rpm for 10 min. The black nanoparticles obtained by pouring off the supernatant were platinum-ruthenium nanoparticles.

[0069] KB600 was calcined in air at 185 °C for 4 h and ground until evenly dispersed to obtain carbon powder. 250 mg of carbon powder was dispersed in 80 mL of chloroform to obtain a carbon powder suspension.

[0070] 250 mg of platinum-ruthenium nanoparticles were dispersed in 80 mL of chloroform to obtain a platinum-ruthenium nanoparticle suspension. The platinum-ruthenium nanoparticle suspension and the carbon powder suspension were mixed in a ratio of 0.57:1 by mass of platinum-ruthenium nanoparticles to carbon powder and shaken evenly, and then filtered and dried with n-hexane to obtain a catalyst precursor.

[0071] The catalyst precursor was heated to 400 °C in an argon-hydrogen atmosphere (the volume ratio of hydrogen in the argon-hydrogen atmosphere was 5%) and kept for 1 h, then naturally cooled, and then heated to 185 °C in an air atmosphere and kept for 2 h, and then naturally cooled to obtain the PtRu-2 electrocatalyst of Example 3.

[0072] The TEM image of the PtRu-2 electrocatalyst prepared in Example 3 is as follows Figure 9 shown, and the XRD pattern is as follows Figure 10 shown.

[0073] The RED test was carried out on the PtRu-2 electrocatalyst prepared in Example 3. 5 mg of the catalyst was put into 500 μL of ultrapure water and sonicated to form an ink, and the ink was dropped on the surface of the platinum-carbon electrode at a ratio of 10 μL per square centimeter. Nafion solution was dropped at a ratio of 15 μL per square centimeter as an adhesive to make a working electrode. In the electrolytic cell, a 0.1 M KOH solution was used as the electrolyte, a reversible hydrogen was used as the reference electrode, and a platinum wire was used as the counter electrode. Before each test, the electrolyte was purged with argon, and then hydrogen was introduced to reach the saturated state. The working electrode was maintained at 0 V for 2 s to eliminate cation adsorption. The HOR polarization curves of the PtRu-2 electrocatalysts of Comparative Example 1 and Example 3 were measured at a scan rate of 20 mV / s in a 0.1 M KOH solution saturated with H2 by RDE test. The comparison diagram of the measured polarization curves is as follows Figure 11 (In the figure, 40% Pt / C is Comparative Example 1, and PtRu-2 is Example 3) shown.

[0074] The anti-CO poisoning test was carried out on the PtRu-2 electrocatalyst prepared in Example 3. Argon was introduced into the electrolytic cell containing a 0.1 M KOH solution for 30 min, and then a reversible hydrogen was prepared in the 0.1 M KOH solution as the reference electrode, and a platinum wire was used as the counter electrode. The above-prepared working electrode was used as a three-electrode system. After the preparation of the reversible hydrogen, the working electrode was activated in the saturated Ar electrolyte at a rate of 50 mV / s between 0.05 V and 0.8 V vs. RHE until a stable CV curve was obtained. After the activation, the background current was measured, and then a CO curve sweep was carried out at a rate of 50 mV / s between -0.05 V and 0.8 V vs. RHE at a rotation speed of 900 rpm to obtain a CO sweep curve. The comparison diagram of the CO sweep curves of Comparative Example 1 and Example 3 is as follows Figure 12 (In the figure, 40% Pt / C is Comparative Example 1, and PtRu-2 is Example 3) shown.

[0075] It can be found by comparison that the catalyst prepared by the preparation method of the present application has good catalytic performance, anti-CO poisoning performance and stability. Even after subsequent air calcination, it will not cause large agglomeration of the catalyst or a significant decrease in performance. The comprehensive performance is also far superior to that of general commercial platinum-carbon catalysts, and it has better use performance and stability in practical applications. The catalyst material prepared in the examples of the present application has excellent anti-CO poisoning while realizing large-scale preparation of hundreds of grams, and is suitable for the anode catalyst of fuel cells, and has great practical value in the field of new energy electric vehicles.

[0076] It should be understood that the application of the present application is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations shall fall within the protection scope of the present application.

Claims

1. A method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst, characterized in that: The following steps are involved: The platinum ruthenium nanoparticle suspension and the carbon powder suspension are mixed evenly, and then the solid is separated to obtain a catalyst precursor; The catalyst precursor is annealed in a reducing atmosphere and then cooled to obtain the fuel cell CO-poisoning resistant PtRu electrocatalyst.

2. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 1, characterized in that: The platinum ruthenium nanoparticle suspension is prepared by dispersing platinum ruthenium nanoparticles in an organic solvent; the carbon powder suspension is prepared by dispersing carbon powder in an organic solvent; The organic solvent is chloroform.

3. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 2, characterized in that: The platinum ruthenium nanoparticle suspension and the carbon powder suspension are mixed in a ratio of 0.4-0.8:1 in terms of the mass ratio of the platinum ruthenium nanoparticles to the carbon powder.

4. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 1, characterized in that: The annealing temperature is 200-800° C., and the insulation time is 0.1-10 h.

5. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 2, characterized in that: Every 250 mg of the platinum ruthenium nanoparticles are dispersed in 10-1000 mL of an organic solvent; The method for preparing the platinum ruthenium nanoparticles comprises the following steps: Platinum precursor and ruthenium precursor are added to a mixed solution consisting of oleylamine, diphenyl ether and o-diphenyl ether, and then 1,2-diol is added. The mixture is heated under an inert atmosphere to complete the reaction, and then cooled and centrifuged to obtain a solid.

6. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 5, characterized in that: The platinum precursor is platinum acetylacetonate, and the ruthenium precursor is ruthenium acetylacetonate; The molar ratio of the platinum precursor to the ruthenium precursor is 1-3:1-10; For every 0.1-3 g of the platinum precursor, 10-30 mL of oleylamine, 80-120 mL of diphenyl ether, 5-15 mL of o-diphenyl ether and 0.6-0.7 g of 1,2-dihydric decanediol are used.

7. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 5, characterized in that: The inert atmosphere is argon; The heating temperature is 200-300°C and the heating time is 5-100min; The centrifugation is performed by placing the mixture obtained after the reaction in a centrifuge tube of a centrifuge, adding 5 g of anhydrous ethanol per 1 g of the mixture, centrifuging at 8000-12000 rpm for 10-20 min, and then discarding the supernatant.

8. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 2, characterized in that: Every 250 mg of carbon powder is dispersed in 10-1000 mL of organic solvent; The carbon powder is obtained by calcining the carbon material at 185° C. for 4 hours and then grinding it; The carbon material is one or more of Vulcan XC72, KB300, KB600, BP2000, Toray carbon, and amorphous carbon.

9. The method for preparing a fuel cell anti-CO poisoning PtRu electrocatalyst according to claim 1, characterized in that: The solid is separated and dried by suction filtration using n-hexane; The reducing atmosphere is an argon-hydrogen atmosphere, and the volume proportion of hydrogen in the argon-hydrogen atmosphere is 5-30%.

10. A fuel cell anti-CO poisoning PtRu electrocatalyst, characterized in that: The catalyst is prepared by the method for preparing the fuel cell CO-poisoning resistant PtRu electrocatalyst as described in any one of claims 1 to 9.

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