Carbon-supported platinum-ruthenium catalyst, membrane electrode and preparation method and application of carbon-supported platinum-ruthenium catalyst and membrane electrode

Abstract

The invention relates to a carbon-supported platinum-ruthenium catalyst, a membrane electrode and a preparation method and application of the carbon-supported platinum-ruthenium catalyst. The catalyst comprises a carrier and an active component supported on the carrier, the carrier is a sulfur modified carbon carrier, and the active components comprise Pt and Ru; wherein in an XRD spectrogram of the catalyst, a Pt (111) characteristic peak exists when 2 theta is 39.7-39.9 degrees, a Pt (220) characteristic peak exists when 2 theta is 67.4-67.5 degrees, the ratio of the unit mass metal normalization peak intensity of the Pt (111) characteristic peak to the full width at half maximum is not larger than 1.0, and the ratio of the unit mass metal normalization peak intensity of the Pt (220) characteristic peak to the full width at half maximum is not larger than 0.1. Compared with a commercial catalyst, the catalyst disclosed by the invention has higher activity and toxicity resistance, and has better tolerance to H2S.

Description

Technical Field

[0001] This disclosure relates to the field of electrochemical technology, specifically to a carbon-supported platinum-ruthenium catalyst, a membrane electrode, and its preparation method and application. Background Technology

[0002] Platinum-carbon catalysts are commonly used in electrocatalysis and serve as anode and cathode catalysts in proton exchange membrane hydrogen fuel cells. While Pt / C catalysts exhibit high activity as anode catalysts, they suffer from poor resistance to poisoning. Trace amounts of H2S impurities in H2 strongly adsorb onto the surface of the noble metal Pt, causing cumulative and irreversible poisoning of the catalyst. This necessitates extremely high H2S requirements in national standards for hydrogen fuel cells, demanding levels below 4 ppb, which drastically increases the cost of hydrogen purification. Therefore, resistance to H2S toxicity is crucial for anode catalysts used in proton exchange membrane fuel cells.

[0003] Because H2S has a strong poisoning effect on Pt, current research on catalysts to combat H2S poisoning mainly focuses on PtRu / C catalysts. However, current PtRu / C catalysts have not yet been widely used due to activity and stability issues, and their resistance to poisoning still needs further improvement. Therefore, developing PtRu / C catalysts with high resistance to poisoning, high activity, and high stability, and applying them to membrane electrode assemblies, is key to solving the rapid degradation of hydrogen fuel cell anodes when exposed to sulfur-containing poisons in practical applications. Summary of the Invention

[0004] The purpose of this disclosure is to provide a carbon-supported platinum-ruthenium catalyst, a membrane electrode, a method for preparing the catalyst, and its application. Compared with commercial catalysts, this catalyst has higher activity and resistance to poisoning, and better tolerance to H2S.

[0005] To achieve the above objectives, a first aspect of this disclosure provides a catalyst comprising a support and an active component supported on the support; the support is a sulfur-modified carbon support, and the active component comprises Pt and Ru; In the XRD spectrum of the catalyst, there is a Pt (111) characteristic peak at 2θ of 39.7~39.9° and a Pt (220) characteristic peak at 2θ of 67.4~67.5°. The ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is not greater than 1.0, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is not greater than 0.1.

[0006] Optionally, the active component is formed as an atomic cluster, the average particle size of which is 1.0~3.0 nm.

[0007] Optionally, in the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.2 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV.

[0008] Optionally, based on the total mass of the catalyst, the mass fraction of platinum is 1-50%, preferably 5-40%; the mass fraction of ruthenium is 1-40%, preferably 5-30%; and the atomic ratio of Pt to Ru is 0.5-2:1.

[0009] Optionally, the sulfur-modified carbon support is sulfur-modified conductive carbon black; in the sulfur-modified carbon support, the total sulfur content is 1-8% by weight, preferably 3-6% by weight. Preferably, the sulfur content on the surface of the sulfur-modified carbon support is 0.1-6% by weight, and more preferably 0.5-3% by weight.

[0010] A second aspect of this disclosure provides a method for preparing a carbon-supported platinum-ruthenium catalyst, the method comprising: A platinum source, a ruthenium source, a sulfur-modified carbon support, and a reducing agent were mixed to obtain a mixed solution. The pH of the mixed solution was adjusted to 10-12. The pH-adjusted mixed solution was reacted at 110-150℃. After the reaction was completed, the solution was washed until the pH of the filtrate was neutral. The reaction product was then dried. The reducing agent includes a polyol having 2 to 3 carbon atoms.

[0011] Optionally, the mixing conditions include: being carried out under stirring conditions for 8 to 14 hours; the reducing agent includes one or more of ethylene glycol and 1,2-propanediol, preferably ethylene glycol; The reaction conditions include a temperature of 120-150°C and a time of 1-4 hours.

[0012] Optionally, the platinum source is a platinum-containing soluble compound, which includes one or more of chloroplatinic acid, chloroplatinate, tetraammineplatinum acetate, and platinum acetylacetonate; the ruthenium source is a ruthenium-containing soluble compound, which includes one or more of ruthenium trichloride and ammonium ruthenium chloride.

[0013] Optionally, the amount of platinum source, calculated as platinum element, is 0.01~1.0 g relative to 1 g of the sulfur-modified carbon support; and the amount of ruthenium source, calculated as ruthenium element, is 0.01~1.0 g relative to 1 g of the sulfur-modified carbon support.

[0014] Optionally, the method for preparing the sulfur-modified carbon support includes: impregnating the carbon support with a solution containing sulfur; The conditions for the impregnation treatment include: a temperature of 10~80℃, a time of 1~5h, and a weight ratio of carbon carrier to sulfur of 2~20:1. The carbon carrier is conductive carbon black; the surface oxygen content of the conductive carbon black is 4% by weight or more; the resistivity of the conductive carbon black is less than 10 Ω·m; and the specific surface area of ​​the conductive carbon black is 200~2000 m². 2 / g.

[0015] The third aspect of this disclosure provides a carbon-supported platinum-ruthenium catalyst prepared by the method described in the second aspect of this disclosure.

[0016] The fourth aspect of this disclosure provides an anti-poisoning membrane electrode, the membrane electrode comprising a proton exchange membrane and an anode catalyst layer coated on one side of the proton exchange membrane, the anode catalyst layer comprising the catalysts described in the first and third aspects of this disclosure.

[0017] The fifth aspect of this disclosure provides the application of the catalyst described in the first and third aspects of this disclosure or the membrane electrode described in the fourth aspect of this disclosure in a fuel cell.

[0018] Through the above technical solution, the catalyst disclosed herein comprises a sulfur-modified carbon support and an active component supported on the support; the active component is formed as atomic clusters. In the catalyst disclosed herein, the active component exists in the form of atomic clusters, exhibiting high dispersion and higher activity and resistance to toxicity compared to commercial catalysts, as well as superior tolerance to H2S.

[0019] Other features and advantages of this disclosure will be described in detail in the following detailed description section. Attached Figure Description

[0020] The accompanying drawings are provided to further illustrate the present disclosure and form part of the specification. They are used together with the following detailed description to explain the present disclosure, but do not constitute a limitation thereof. In the drawings: Figure 1 These are the XRD patterns of the carbon-supported platinum-ruthenium catalysts of Example 1 and Comparative Examples 1-3 of this disclosure.

[0021] Figure 2 This is the XPS spectrum of the carbon-supported platinum-ruthenium catalyst S 2p of Example 1 of this disclosure.

[0022] Figure 3 These are XPS spectra of the carbon-supported platinum-ruthenium catalyst Ru 3p of Example 1 and Comparative Examples 1-3 of this disclosure.

[0023] Figure 4 These are XPS spectra of the carbon-supported platinum-ruthenium catalyst Pt 4f of Example 1 and Comparative Examples 1-3 of this disclosure.

[0024] Figure 5 This is a STEM diagram of Embodiment 1 of this disclosure.

[0025] Figure 6 This is the STEM diagram of Comparative Example 2 of this publication.

[0026] Figure 7 This is the constant voltage curve of the carbon-supported platinum-ruthenium catalyst of Example 1 of this disclosure to resist H2S toxicity.

[0027] Figure 8 This is the voltage-constant curve of the carbon-supported platinum-ruthenium catalyst of Comparative Example 2 of this disclosure to resist H2S toxicity. Detailed Implementation

[0028] The specific embodiments of this disclosure will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit this disclosure.

[0029] The first aspect of this disclosure provides a catalyst comprising a support and an active component supported on the support; the support is a sulfur-modified carbon support, and the active component comprises Pt and Ru; In the XRD spectrum of the catalyst, there is a Pt (111) characteristic peak at 2θ of 39.7~39.9° and a Pt (220) characteristic peak at 2θ of 67.4~67.5°. The ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is not greater than 1.0, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is not greater than 0.1.

[0030] The catalyst disclosed herein comprises a sulfur-modified carbon support and an active component supported on the support; the active component is formed as atomic clusters. In the catalyst disclosed herein, the active component exists in the form of atomic clusters, exhibiting high dispersion, higher activity and resistance to toxicity compared to commercial catalysts, and superior tolerance to H2S.

[0031] According to one embodiment of the present disclosure, in the XRD spectrum of the catalyst, the ratio of the normalized metal intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is 0.05 to 0.1, and the ratio of the normalized metal intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is 0.008 to 0.08.

[0032] According to one embodiment of this disclosure, the active component is formed as atomic clusters, the average particle size of which is 1.0~3.0 nm, preferably 1.5~2.8 nm. This embodiment is beneficial for improving the activity and resistance to poisoning of the catalyst.

[0033] According to one embodiment of this disclosure, in the XPS spectrum of the catalyst, the 4f 7 / 2 characteristic peak of Pt is located at 71.4 ± 0.3 eV, and the 3p 3 / 2 characteristic peak of Ru is located at 461.9~463.4 eV. In commercial catalysts, the 3p 3 / 2 characteristic peak of Ru is typically located around 461.4 eV. Compared to commercial catalysts, the 3p 3 / 2 characteristic peak of Ru in the catalyst of this disclosure is shifted to a higher electron volt level by 0.4~2.0 eV, indicating that the valence state of Ru in the catalyst of this disclosure is mostly changed from 0 to +2 and +4, which is beneficial to improving the activity of the catalyst.

[0034] According to one embodiment of this disclosure, based on the total mass of the catalyst, the mass fraction of platinum is 1-50%, preferably 5-40%; the mass fraction of ruthenium is 1-40%, preferably 5-30%; and the atomic ratio of Pt to Ru is 0.5-2:1, preferably 1-2:1. Compared to commercial catalysts, the catalyst of this disclosure has a lower metal loading and better activity and resistance to poisoning.

[0035] According to one embodiment of this disclosure, the sulfur-modified carbon support is sulfur-modified conductive carbon black; in the sulfur-modified carbon support, the total sulfur content is 1-8% by weight, preferably 3-6% by weight; preferably, the surface sulfur content in the sulfur-modified carbon support is 0.1-6% by weight, preferably 0.5-3% by weight. The above embodiment is beneficial for highly dispersing the active component on the support, and is beneficial for improving the activity and anti-toxicity of the catalyst.

[0036] A second aspect of this disclosure provides a method for preparing a carbon-supported platinum-ruthenium catalyst, the method comprising: A platinum source, a ruthenium source, a sulfur-modified carbon support, and a reducing agent were mixed to obtain a mixed solution. The pH of the mixed solution was adjusted to 10-12. The pH-adjusted mixed solution was reacted at 110-150℃. After the reaction was completed, the solution was washed until the pH of the filtrate was neutral. The reaction product was then dried. The reducing agent includes alcohols having 2 to 3 carbon atoms.

[0037] According to one embodiment of this disclosure, the mixing conditions include: carrying out the mixture under stirring conditions for 8 to 14 hours. This embodiment facilitates a more uniform mixing of the metal and the carrier.

[0038] According to one embodiment of this disclosure, the reaction conditions include a temperature of 120-150°C and a time of 1-4 hours. This embodiment facilitates the formation of atomic clusters of the active component, thereby improving the catalyst's activity and resistance to poisoning.

[0039] According to one embodiment of this disclosure, the platinum source is a platinum-containing soluble compound, which includes one or more of chloroplatinic acid, chloroplatinate, tetraammineplatinum acetate, and platinum acetylacetonate; the ruthenium source is a ruthenium-containing soluble compound, which includes one or more of ruthenium trichloride and ammonium ruthenium chloride.

[0040] According to one embodiment of this disclosure, the reducing agent includes one or more of ethylene glycol and 1,2-propanediol, preferably ethylene glycol. The above embodiment is advantageous for obtaining catalysts with superior activity and resistance to toxicity.

[0041] According to one embodiment of this disclosure, the amount of platinum source, calculated as platinum element, is 0.01 to 1.0 g relative to 1 g of the sulfur-modified carbon support; and the amount of ruthenium source, calculated as ruthenium element, is 0.01 to 1.0 g relative to 1 g of the sulfur-modified carbon support.

[0042] According to one embodiment of this disclosure, the method for preparing the sulfur-modified carbon support includes: impregnating the carbon support with a solution containing sulfur. This embodiment is beneficial for improving the catalyst's resistance to poisoning.

[0043] According to one embodiment of this disclosure, the impregnation treatment conditions include: a temperature of 10~80℃, preferably 20~60℃, a time of 1~5h, preferably 2~4h, and a weight ratio of carbon carrier to sulfur of 2~20:1, preferably 2~15:1; the carbon carrier is conductive carbon black; the surface oxygen content of the conductive carbon black is 4% by weight or more; the resistivity of the conductive carbon black is 10Ω·m or less; and the specific surface area of ​​the conductive carbon black is 200~2000m². 2 / g. The above-described embodiments are beneficial for improving the catalyst's resistance to poisoning. In this disclosure, the surface oxygen content of conductive carbon black refers to the oxygen content analyzed by XPS testing.

[0044] According to one embodiment of this disclosure, the conductive carbon black includes one or more of EC-300J, EC-600JD, ECP600JD, VXC72, VXC72R, Black Pearls 2000, PRINTEX XE2-B, PRINTEX L6, and HIBLAXK 40B2.

[0045] The third aspect of this disclosure provides a carbon-supported platinum-ruthenium catalyst prepared by the method described in the second aspect of this disclosure.

[0046] The fourth aspect of this disclosure provides an anti-poisoning membrane electrode, the membrane electrode comprising a proton exchange membrane and an anode catalyst layer coated on one side of the proton exchange membrane, the anode catalyst layer comprising the catalysts described in the first and third aspects of this disclosure.

[0047] The fifth aspect of this disclosure provides the application of the catalyst described in the first and third aspects of this disclosure or the membrane electrode described in the fourth aspect of this disclosure in a fuel cell.

[0048] The present disclosure will be further described in detail below with reference to the embodiments. Unless otherwise specified, all reagents in this disclosure are commercially available.

[0049] Instruments, methods and conditions for XRD analysis: X-ray diffraction (XRD) analysis was performed on a Shimadzu XRD-6000 X-ray diffractometer from Japan. The test conditions included: tube voltage 40 kV, tube current 40 mA, Cu target Kα radiation, and 2θ scan range of 10° to 80°.

[0050] The X-ray photoelectron spectroscopy (XPS) analyzer was a VG Scientific ESCALab220i-XL model equipped with Avantage V5.926 software. The XPS analysis conditions were as follows: excitation source was monochromatic AlKα X-rays, power was 330 W, and the baseline vacuum was 3 × 10⁻⁶. -9 mbar. In addition, the electron binding energy was corrected using the C1s peak (284.3 eV) of elemental carbon, and the subsequent peaking software was XPSPEAK.

[0051] Instruments, methods, and conditions for testing the mass fraction of platinum and ruthenium in carbon-supported platinum-ruthenium catalyst: Take 30 mg of the prepared catalyst, add 30 mL of aqua regia, reflux at 120 °C for 12 h, cool to room temperature, take the supernatant, dilute it, and test the Pt and Ru content by ICP-AES.

[0052] The total sulfur content was tested using a sulfur-carbon analyzer; the surface sulfur content was tested using an X-ray photoelectron spectroscopy analyzer.

[0053] Aberration-corrected transmission electron microscopy (AC-STEM) was used, specifically the JEOL ARM200F model. The morphology and particle size of the metal particles were measured using STEM. The average particle size of the nanocrystals was calculated by taking 200 metal particles from the STEM image and calculating their average size.

[0054] Ketjenblack ECP600JD (manufactured by Lion Corporation, Japan). Using the aforementioned instrumental methods, the results show a specific surface area of ​​1362 m². 2 / g, pore volume 2.29mL / g, surface oxygen mass fraction 6.9wt%.

[0055] Commercial carbon-supported platinum-ruthenium catalyst (brand name TEC61E54DM, manufactured by Tanaka) with a total metal loading of 54 wt% and an atomic ratio of Pt to Ru of 1:1.5.

[0056] The following preparation examples are used to prepare sulfur-modified carbon supports.

[0057] Preparation Example 1 0.25 g of sulfur was dissolved in 70 ml of cyclohexane to form a homogeneous solution. 9.75 g of Ketjenblack ECP600JD was dispersed in the solution, stirred until homogeneous, impregnated for 5 h, and then vacuum dried at 50 °C to obtain sulfur-modified carbon conductive carbon black, designated as carbon support A. In carbon support A, the total sulfur content was 2.5% by weight; the surface sulfur content was 1.8% by weight.

[0058] Preparation Example 2 0.55 g of sulfur was dissolved in 70 ml of cyclohexane to form a homogeneous solution. 9.45 g of Ketjenblack ECP600JD was dispersed in the solution, stirred until homogeneous, impregnated for 5 h, and then vacuum dried at 50 °C to obtain sulfur-modified conductive carbon black, designated as carbon support B. In carbon support B, the total sulfur content was 5.5 wt%; the surface sulfur content was 3.5 wt%.

[0059] The following examples are used to prepare catalysts.

[0060] Example 1 Relative to each gram of carbon support, 2.30 mmol of chloroplatinic acid and 2.30 mmol of ruthenium trichloride were used. First, chloroplatinic acid and ruthenium trichloride were dissolved in 80 ml of ethylene glycol. 0.2 g of carbon support A was dispersed in the metal solution and stirred evenly for 10 h. Then, NaOH solution was added to adjust the pH to 10, and the mixture was placed in an oven at 120 °C for 4 h. After washing the filtrate with deionized water until neutral, it was dried under vacuum to obtain the catalyst.

[0061] Example 2 The method in this embodiment is the same as in Example 1, except that 2.77 mmol of chloroplatinic acid and 1.38 mmol of ruthenium chloride are added per gram of carbon support to obtain a Pt2Ru1 / C catalyst, with an atomic ratio of Pt to Ru of 2:1.

[0062] Example 3 The method in this embodiment is the same as that in Example 1, except that carbon support B is used to obtain the Pt1Ru1 / C catalyst.

[0063] Example 4 The method in this embodiment is the same as that in embodiment 1, except that the reaction conditions in this embodiment are 110°C and the reaction time is 6 hours.

[0064] Example 5 The method in this embodiment is the same as in Example 1, except that 1.69 mmol of chloroplatinic acid and 3.38 mmol of ruthenium chloride are added per gram of carbon support to obtain the Pt1Ru2 / C catalyst, with an atomic ratio of Pt to Ru of 0.5:1.

[0065] Comparative Example 1 The carbon-supported platinum-ruthenium catalyst was prepared according to the method in Example 1, with the only difference being that the support was an unmodified carbon support, Ketjenblack ECP600JD.

[0066] Comparative Example 2 Commercial carbon-supported platinum-ruthenium catalyst, grade TEC61E54DM.

[0067] Comparative Example 3 The method used in this comparative example is the same as in Example 1, except that 2.30 mmol of chloroplatinic acid and 2.30 mmol of ruthenium trichloride are used per gram of carbon support. First, chloroplatinic acid and ruthenium trichloride are dissolved in 80 ml of an aqueous solution containing 25% ethanol. 0.2 g of carbon support A is dispersed in the metal solution and stirred evenly for 10 h. The mixture is then dried in an oven at 60 °C to obtain the precursor. The precursor is ground and placed in a tube furnace, heated to 150 °C, and heat-treated for 2 h in an atmosphere of N2:H2 = 4:1. The temperature is then lowered under the N2 atmosphere to obtain the catalyst.

[0068] Test Example 1 The catalysts obtained in Examples 1-5 and Comparative Examples 1-3 were subjected to XRD, XPS, and STEM tests. The XRD results are as follows: Figure 1 As shown, the XPS spectrum of S2p is as follows: Figure 2 As shown, the characteristic peaks of Ru 3p in the XPS test are as follows: Figure 3 As shown, the characteristic peaks of Pt 4f obtained by XPS testing are as follows: Figure 4 As shown, the results of STEM are as follows: Figures 5-6 As shown.

[0069] from Figures 1-5It can be seen that in the XRD pattern of the catalyst in Example 1, there is no characteristic peak of Ru, but there is a characteristic peak of Pt (111) at 2θ of 39.8° and a characteristic peak of Pt (220) at 2θ of 67.4°. The ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is 0.66, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is 0.08. The absence of a characteristic peak of Ru in the XRD pattern indicates that Ru is highly dispersed as single atoms in the atomic clusters. The characteristic peak of Ru 3p is located at 461.94 eV, shifted to a higher electron volt by 0.54 eV, indicating that Ru is biased towards a higher valence state. The characteristic peak of Pt 4f is located at 71.44 eV. The XPS pattern of S 2p indicates the presence of S element in the support. In the STEM image, it can be seen that the active component of the catalyst exists in the form of atomic clusters, with an average particle size of 2.0 nm.

[0070] The XRD spectra of Examples 2-5 are the same as those of Example 1. The characteristic peaks of Pt (111) are all located at 39.7°~39.9°, and the characteristic peaks of Pt (220) are present at 2θ of 67.4~67.5°. The ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is not greater than 1.0, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is not greater than 0.1. There are no characteristic peaks of Ru in the XRD spectra. The XPS spectra of Examples 2-5 are the same as those of Example 1. The characteristic peaks of Ru 3p are all located at 461.9~463.4 eV, and the characteristic peak of Pt 4f is located at 71.4±0.2 eV.

[0071] The XRD spectrum of Comparative Example 1 is similar to that of Example 1. In the XPS spectrum, the characteristic peak of Ru 3p is located at 462.47 eV, and the range is between 461.9 and 463.4 eV, indicating that more Ru in Comparative Example 1 is in a higher valence state. However, the characteristic peak of Pt 4f is located at 71.70 eV, indicating that Pt is shifted towards a higher valence state. In the XRD spectrum of the catalyst of Comparative Example 2, the characteristic peak of Pt (111) is located at 40.8°, indicating a shift in peak position. The peak position is not at the location of Pt and Ru. Furthermore, the ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is 2.98, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is 0.36, indicating that Pt and Ru in the catalyst of Comparative Example 2 do not form atomic clusters. Figure 6The STEM image further shows that in the XPS image, the Ru 3p characteristic peak is located at 461.42 eV, and the valence state of Ru is mainly 0. The XRD spectrum of Comparative Example 3 has the same ratio of normalized peak intensity to full width at half maximum (FWHM) per unit mass as that of Example 1, but its Pt (111) characteristic peak is located at 39.3°, the Ru 3p characteristic peak is located at 463.05 eV in the XPS image, and the Pt 4f characteristic peak is located at 71.89 eV.

[0072] Test Example 2 The catalysts prepared in Examples 1-5 and Comparative Examples 1-3 were used to prepare film electrodes, and their electrocatalytic hydrogenation reaction performance was tested. The results are shown in Table 1.

[0073] Methods for preparing catalysts into film electrodes include: (1) Preparation of slurry for catalyst layer Cathode catalyst slurry: Weigh 1g of 40wt% Pt / C (HISPEC4000, produced by Johnson Matthey) catalyst, add 26.6g of water, disperse evenly, add 46.6g of isopropanol and 9g of 5wt% Nafion solution, mix evenly and set aside.

[0074] Anode catalyst slurry: Weigh 1g of platinum-ruthenium catalyst prepared in Examples 1-5 and Comparative Examples 1-3 respectively, add 26.6g of water, disperse evenly, add 46.6g of isopropanol and 9g of 5wt% Nafion solution, mix evenly and set aside.

[0075] (2) Preparation of membrane electrode The cathode catalyst layer slurry and the anode catalyst layer slurry were coated on both sides of the proton exchange membrane by spraying, and then cured to form the cathode catalyst layer and the anode catalyst layer, so that the platinum loading in both the cathode and anode catalyst layers was 0.1 mg / cm³. 2 The effective area of ​​the membrane electrode is 5 cm². 2 .

[0076] The testing instrument was a Scribner 850e.

[0077] Test Example 3 The H2S toxicity resistance of the catalysts prepared in Examples 1-5 and Comparative Examples 1-3 was determined, and the results are shown in Table 1 and 2. Figures 7-8 As shown.

[0078] The testing instrument was a Scribner 850e; the testing method included introducing oxygen into the cathode, introducing hydrogen into the anode first, and then introducing hydrogen containing a certain concentration of H2S at different times.

[0079] Table 1

[0080] As can be seen from the data in Table 1, the catalyst of this disclosure has a lower loading of active components compared to the commercial catalyst in Comparative Example 2, but exhibits higher activity and better resistance to poisoning. A comparison of Examples 1 and 4 shows that within the preferred molar ratio of platinum source to ruthenium source in this disclosure, the obtained catalyst exhibits higher activity and better resistance to poisoning. A comparison of Examples 1 and 5 shows that within the preferred reaction conditions of this disclosure, the obtained catalyst exhibits higher activity and better resistance to poisoning.

[0081] The preferred embodiments of this disclosure have been described in detail above with reference to the accompanying drawings. However, this disclosure is not limited to the specific details of the above embodiments. Within the scope of the technical concept of this disclosure, various simple modifications can be made to the technical solutions of this disclosure, and these simple modifications all fall within the protection scope of this disclosure.

[0082] It should also be noted that the various specific technical features described in the above embodiments can be combined in any suitable manner without contradiction. To avoid unnecessary repetition, this disclosure will not describe the various possible combinations separately.

[0083] Furthermore, various different embodiments of this disclosure can be combined in any way, as long as they do not violate the spirit of this disclosure, they should also be regarded as the content disclosed in this disclosure.

Claims

1. A carbon-supported platinum-ruthenium catalyst, characterized in that, The catalyst comprises a support and an active component supported on the support; the support is a sulfur-modified carbon support, and the active component comprises Pt and Ru; In the XRD spectrum of the catalyst, there is a Pt (111) characteristic peak at 2θ of 39.7~39.9° and a Pt (220) characteristic peak at 2θ of 67.4~67.5°. The ratio of the normalized peak intensity per unit mass of the Pt (111) characteristic peak to the full width at half maximum (FWHM) is not greater than 1.0, and the ratio of the normalized peak intensity per unit mass of the Pt (220) characteristic peak to the full width at half maximum (FWHM) is not greater than 0.

1.

2. The catalyst according to claim 1, wherein, The active component is formed into atomic clusters, and the average particle size of the atomic clusters is 1.0~3.0 nm.

3. The catalyst according to claim 1, wherein, In the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.2 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV.

4. The catalyst according to claim 1, wherein, Based on the total mass of the catalyst, the mass fraction of platinum is 1-50%, preferably 5-40%; the mass fraction of ruthenium is 1-40%, preferably 5-30%; and the atomic ratio of Pt to Ru is 0.5-2:

1.

5. The catalyst according to claim 1, wherein, The sulfur-modified carbon support is sulfur-modified conductive carbon black; in the sulfur-modified carbon support, the total sulfur content is 1-8% by weight, preferably 3-6% by weight. Preferably, the sulfur content on the surface of the sulfur-modified carbon support is 0.1-6% by weight, and more preferably 0.5-3% by weight.

6. A method for preparing a carbon-supported platinum-ruthenium catalyst, characterized in that, The method includes: A platinum source, a ruthenium source, a sulfur-modified carbon support, and a reducing agent were mixed to obtain a mixed solution. The pH of the mixed solution was adjusted to 10-12. The pH-adjusted mixed solution was reacted at 110-150℃. After the reaction was completed, the solution was washed until the pH of the filtrate was neutral. The reaction product was then dried. The reducing agent includes a polyol having 2 to 3 carbon atoms.

7. The method according to claim 6, wherein, The mixing conditions include: being carried out under stirring for 8-14 hours; the reducing agent includes one or more of ethylene glycol and 1,2-propanediol, preferably ethylene glycol; The reaction conditions include a temperature of 120-150°C and a time of 1-4 hours.

8. The method according to claim 6, wherein, The platinum source is a platinum-containing soluble compound, which includes one or more of chloroplatinic acid, chloroplatinate, tetraammineplatinum acetate, and platinum acetylacetonate; the ruthenium source is a ruthenium-containing soluble compound, which includes one or more of ruthenium trichloride and ammonium ruthenium chloride.

9. The method according to claim 6, wherein, The amount of platinum source, calculated as platinum element, is 0.01~1.0 g relative to 1 g of the sulfur-modified carbon support; the amount of ruthenium source, calculated as ruthenium element, is 0.01~1.0 g relative to 1 g of the sulfur-modified carbon support.

10. The preparation method according to claim 6, wherein, The method for preparing the sulfur-modified carbon support includes: impregnating the carbon support with a solution containing sulfur. The conditions for the impregnation treatment include: a temperature of 10~80℃, a time of 1~5h, and a weight ratio of carbon carrier to sulfur of 2~20:

1. The carbon carrier is conductive carbon black; the surface oxygen content of the conductive carbon black is 4% by weight or more; the resistivity of the conductive carbon black is less than 10 Ω·m; and the specific surface area of ​​the conductive carbon black is 200~2000 m². 2 / g.

11. A carbon-supported platinum-ruthenium catalyst prepared by the method according to any one of claims 6 to 10.

12. A poison-resistant membrane electrode, characterized in that, The membrane electrode includes a proton exchange membrane and an anode catalyst layer coated on one side of the proton exchange membrane, wherein the anode catalyst layer includes the catalyst according to any one of claims 1 to 5 and 11.

13. The application of the catalyst according to any one of claims 1 to 5 and 11 or the membrane electrode according to claim 12 in a fuel cell.

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