Carbon-supported platinum-ruthenium catalyst, its preparation method and application

Abstract

The present disclosure relates to a carbon-supported platinum-ruthenium catalyst, a preparation method and application thereof, the catalyst comprising a carbon carrier and an active component supported on the carbon carrier, the active component comprising Pt and Ru; in the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.3 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV; in the XRD spectrum of the catalyst, the (111) characteristic peak of Pt exists at 2θ of 39.8°~40.2°. Compared with a commercial carbon-supported platinum-ruthenium catalyst, the catalyst of the present disclosure has better activity and stability, and can greatly reduce the catalyst dosage in a membrane electrode.

Description

Technical Field

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

[0002] Hydrogen energy has the characteristics of high energy density, high calorific value, wide availability, and clean and pollution-free operation. As countries pay increasing attention to global climate change and energy revolution, hydrogen energy, as a clean and efficient energy carrier, has become an important support for building a sustainable society.

[0003] Water electrolysis is currently a relatively mature and simple method for producing hydrogen. It mainly includes alkaline water electrolysis (ALK), proton exchange membrane (PEM) water electrolysis, and anion exchange membrane (AEM) water electrolysis. PEM water electrolysis technology, with its high electrolysis efficiency, safety, reliability, compact structure, and rapid response to renewable energy, is widely recognized as one of the most promising hydrogen production technologies. However, due to the acidic, high-voltage environment of PEM water electrolysis, only the precious metal Ir-based catalyst at the anode is relatively stable. Ir, as a byproduct of Pt, has small reserves, while PEM water electrolysis requires a large amount of Ir, resulting in high costs and limiting its commercialization. Alkaline water electrolysis is currently the most mature water electrolysis technology. It does not require the use of precious metals, resulting in very low equipment manufacturing costs, but its operating current density is very low, typically less than 0.5 A / cm³. 2 This results in extremely large hydrogen production equipment. AEM can combine the advantages of PEM and alkaline water electrolysis, increasing current density and reducing the use of precious metals. However, under alkaline conditions, the kinetics of the hydrogen evolution reaction are 2-3 orders of magnitude lower than under acidic conditions, making the hydrogen evolution reaction crucial. Whether using ALK or AEM for water electrolysis, achieving a high current density (not less than 1 A / cm³) is essential. 2 The cathode still requires a Pt-based catalyst. To reduce costs and the use of Pt, the development of Pt-based alloy catalysts is an important direction. However, the microstructure of alloy catalysts is highly variable, and in most cases, their stability is far lower than that of pure platinum catalysts, which limits their practical application. Summary of the Invention

[0004] The purpose of this disclosure is to provide a carbon-supported platinum-ruthenium catalyst, its preparation method, and its application, which exhibits superior activity and stability.

[0005] To achieve the above objectives, a first aspect of this disclosure provides a carbon-supported platinum-ruthenium catalyst, the catalyst comprising a carbon support and an active component supported on the carbon support, the active component comprising Pt and Ru; In the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.3 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV; in the XRD spectrum of the catalyst, there is a (111) characteristic peak of Pt at 2θ of 39.8°~40.2°.

[0006] Optionally, the active component includes nanocrystals, which contain Pt crystals and Ru dispersed in the Pt crystals; the average particle size of the nanocrystals is 1.2~3.5 nm.

[0007] Optionally, the characteristic peak of Ru is absent in the XRD pattern of the catalyst.

[0008] Optionally, based on the total mass of the catalyst, the total mass fraction of the active component is 15-50%, and the atomic ratio of Pt to Ru is 0.5-2:1.

[0009] Optionally, the carbon support may further include a heteroatom-doped carbon support, wherein the heteroatom includes S and / or N elements.

[0010] A second aspect of this disclosure provides a method for preparing a carbon-supported platinum-ruthenium catalyst, the method comprising: (1) The platinum source, ruthenium source and carbon support are impregnated in a solvent, and the precursor is obtained after removing the solvent; (2) In a reducing atmosphere, the precursor in step (1) is heat-treated at 220~500°C.

[0011] Optionally, in step (1), the carbon support is conductive carbon black; the surface oxygen content of the conductive carbon black is 4% by mass or more; and the specific surface area of ​​the conductive carbon black is 200~2000 m². 2 / g; The platinum source is a platinum-containing soluble compound, including one or more of chloroplatinic acid, chloroplatinate, and tetraammineplatinum acetate; The ruthenium source is a soluble compound containing ruthenium, including one or more of ruthenium trichloride and ammonium ruthenate. The solvent includes one or more of water, alcohol solvents and ketone solvents; preferably, the solvent includes water and / or alcohol solvents, and the alcohol solvent is preferably ethanol.

[0012] Optionally, in step (1), the total mass of the metal source, calculated as metal elements, is 0.17~1.0g relative to 1g of the carbon support, and the molar ratio of the platinum source to the ruthenium source is 0.5~2:1.

[0013] Optionally, in step (1), the soaking time is 10 hours or more, preferably 15 to 24 hours; In step (1), the solvent removal includes drying the impregnated mixture at a temperature below 100°C.

[0014] Optionally, in step (2), the reducing atmosphere includes hydrogen; preferably, the reducing atmosphere includes hydrogen and an inert gas, and the volume content of the hydrogen is 5-30% by volume. The inert gas is preferably nitrogen.

[0015] Optionally, in step (2), the heat treatment conditions include: a temperature of 260~450℃ and a time of 1~4h.

[0016] 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.

[0017] This fourth aspect of the disclosure provides the application of the catalyst described in the first and third aspects of the disclosure in the electrolysis of water.

[0018] Through the above technical solution, the catalyst disclosed herein includes a carbon support and an active component supported on the carbon support. The active component comprises Pt and Ru. 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 the XRD spectrum of the catalyst, the (111) characteristic peak of Pt is present at 2θ of 39.8°~40.2°. In the catalyst of this disclosure, Ru is highly dispersed in the crystal structure of Pt, but the crystal lattice structure of Pt is not changed. Pt and Ru form a homogeneous phase, which improves the stability and activity of the catalyst.

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

[0022] Figure 3 These are the LSV curves of the carbon-supported platinum-ruthenium catalysts of Example 1 and Comparative Examples 1-2 of this disclosure.

[0023] Figure 4 This is a STEM diagram of Embodiment 1 of this disclosure.

[0024] Figure 5 This is a STEM diagram of Embodiment 2 of this disclosure.

[0025] Figure 6 This is a STEM diagram of Comparative Example 1 of this publication.

[0026] Figure 7 This is the STEM diagram of Comparative Example 2 of this publication. Detailed Implementation

[0027] 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.

[0028] The first aspect of this disclosure provides a carbon-supported platinum-ruthenium catalyst, the catalyst comprising a carbon support and an active component supported on the carbon support, the active component comprising Pt and Ru; In the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.3 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV; in the XRD spectrum of the catalyst, there is a (111) characteristic peak of Pt at 2θ of 39.8°~40.2°.

[0029] The catalyst disclosed herein comprises a carbon support and an active component supported on the carbon support, the active component comprising Pt and Ru; in the XRD pattern of the catalyst, only the characteristic peak of Pt is present, and the (111) characteristic peak of Pt exists at 2θ of 39.8°~40.2°, indicating that the Pt in the catalyst of this disclosure forms a well-formed nanocrystalline structure, and Ru is dispersed in the Pt crystals without changing the crystal structure of Pt; in the XPS pattern of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.3 eV, without shift, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV, compared with the conventional 3p 3 / 2 characteristic peak of Ru at 461.4 eV, the 3p 3 / 2 characteristic peak of Ru in the catalyst of this application is shifted to a higher electron volt by 0.4~2.0. The presence of eV indicates that, compared to commercial catalysts, the Ru catalyst disclosed herein contains ruthenium in addition to the 0 valence, with +2 and +4 valences, thus improving the catalyst's stability and activity.

[0030] In this disclosure, the XPS spectrum refers to the XPS spectrum corrected with the C1s peak at 284.3 eV.

[0031] In this disclosure, "carbon black" and "carbon black" are interchangeable technical terms.

[0032] In this disclosure, "inert gas" refers to a gas that does not cause any perceptible effect on the performance of the carbon support and catalyst in the preparation method of this disclosure.

[0033] According to one embodiment of this disclosure, the active component comprises nanocrystals, preferably, the active component exists in the form of nanocrystals. Further, the nanocrystals comprise Pt crystals and Ru dispersed within the Pt crystals; the average particle size of the nanocrystals is 1.2~3.5 nm, preferably 1.5~3.0 nm.

[0034] According to one embodiment of this disclosure, the XRD spectrum of the catalyst does not contain characteristic peaks of Ru, but only characteristic peaks of Pt. Ru is highly dispersed in the Pt crystal structure, and the two form a homogeneous phase, which further improves the stability of the catalyst.

[0035] According to one embodiment of this disclosure, based on the total mass of the catalyst, the total mass fraction of the active component is 15-50%, preferably 20-40%; the atomic ratio of Pt to Ru is 0.5-2:1, preferably 1-2:1. Compared with commercial carbon-supported platinum-ruthenium catalysts, the catalyst of this disclosure has a lower loading of active component, higher activity, and better stability.

[0036] According to one embodiment of this disclosure, the carbon support further includes a heteroatom-doped carbon support, wherein the heteroatoms include S and / or N elements. This embodiment facilitates the high dispersion of Ru within the Pt crystal, thereby improving the activity and stability of the catalyst.

[0037] According to one embodiment of this disclosure, the method for preparing the heteroatom-doped carbon support includes: impregnating the carbon support with a solution containing sulfur, and drying the resulting impregnation product. This embodiment facilitates the high dispersion of Ru in the Pt crystals, thereby improving the activity and stability of the catalyst.

[0038] In one embodiment, the impregnation treatment conditions include: a temperature of 10~80℃, preferably 20~60℃, and a time of 1~5h, preferably 2~4h. The above embodiment is beneficial for dispersing Pt crystals and improving the activity and stability of the catalyst.

[0039] A second aspect of this disclosure provides a method for preparing a carbon-supported platinum-ruthenium catalyst, the method comprising: (1) The platinum source, ruthenium source and carbon support are impregnated in a solvent, and the precursor is obtained after removing the solvent; (2) In a reducing atmosphere, the precursor in step (1) is heat-treated at 220~500°C.

[0040] According to one embodiment of this disclosure, in step (1), the carbon support is conductive carbon black, and the surface oxygen content of the conductive carbon black is 4% by mass or more; the specific surface area of ​​the conductive carbon black is 200~2000 m². 2 / g; 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. In this disclosure, the surface oxygen content of the conductive carbon black refers to the oxygen content analyzed by XPS testing.

[0041] According to one embodiment of this disclosure, in step (1), the platinum source is a platinum-containing soluble compound, such as one or more of chloroplatinic acid, chloroplatinate, and tetraammineplatinum acetate.

[0042] According to one embodiment of this disclosure, in step (1), the ruthenium source is a soluble compound containing ruthenium, such as one or more of ruthenium trichloride and ammonium ruthenate.

[0043] According to one embodiment of this disclosure, in step (1), the solvent includes one or more of water, alcohol solvents and ketone solvents; preferably, the solvent includes water and / or alcohol solvents, and the alcohol solvent is preferably ethanol.

[0044] According to one embodiment of this disclosure, in step (1), the total mass of the metal source, calculated as metal element, is 0.17~1.0g, preferably 0.25~0.67g, relative to 1g of the carbon support; the molar ratio of the platinum source to the ruthenium source is 0.5~2:1, preferably 1~2:1. The above embodiment is advantageous in enabling the catalyst of this disclosure to have high activity and stability even with low dosage.

[0045] According to one embodiment of the present disclosure, in step (1), the soaking time is more than 10 hours, preferably 15 to 24 hours; in step (1), the solvent removal includes drying the impregnated mixture at a temperature of less than 100°C, for example, 60 to 95°C.

[0046] According to one embodiment of this disclosure, in step (2), the reducing atmosphere includes hydrogen; preferably, the reducing atmosphere includes hydrogen and an inert gas, wherein the volume content of hydrogen is 5-30% by volume; and the inert gas is preferably nitrogen. The above embodiment facilitates the formation of nanocrystals in the catalyst, thereby improving the activity and stability of the catalyst.

[0047] According to one embodiment of this disclosure, in step (2), the heat treatment conditions include: a temperature of 260~450℃ and a time of 1~4h. This embodiment facilitates the formation of nanocrystals in the catalyst, thereby improving the catalyst's activity and stability.

[0048] 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.

[0049] This fourth aspect of the disclosure provides the application of the catalyst described in the first and third aspects of the disclosure in the electrolysis of water.

[0050] According to one embodiment of this disclosure, the catalyst is used in the cathode of an AEM electrolyzer.

[0051] 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.

[0052] 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°.

[0053] 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.

[0054] 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.

[0055] 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 TEM. The average particle size of the nanocrystals was calculated by taking 200 metal particles from the TEM image and calculating their average size.

[0056] Electrochemical performance testing was conducted using Solartron analytical EnergyLab and Princeton Applied Research (Model 636A) instruments.

[0057] 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%.

[0058] 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.

[0059] Example 1 (1) Using Ketjenblack ECP600JD as the carbon support, chloroplatinic acid and ruthenium trichloride were dissolved in 15 ml of a 1:1 (volume ratio) water-ethanol solution at a ratio of 2.30 mmol chloroplatinic acid and 2.30 mmol ruthenium chloride per gram of carbon support. 1 g of carbon support was dispersed in the above solution, and after uniform dispersion, it was allowed to stand for 16 h and then dried in an oven at 60 °C to obtain the precursor. The total mass of the metal source, calculated as metal element, was 0.67 g relative to 1 g of the carbon support, and the molar ratio of platinum source to ruthenium source was 1:1. (2) The precursor was ground and placed in a tube furnace, heated to 300°C, and heat-treated for 2 hours in an atmosphere with a N2:H2 volume ratio of 4:1. Then, it was cooled in an N2 atmosphere to obtain the Pt1Ru1 / C catalyst. Based on the total mass of the catalyst, the total mass fraction of the active component was 40% by mass, and the atomic ratio of Pt to Ru was 1:1.

[0060] 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. The total mass of the metal source (based on metal element) is 0.67 g relative to 1 g of the carbon support, and the molar ratio of platinum source to ruthenium source is 2:1 to obtain the Pt2Ru1 / C catalyst. Based on the total mass of the catalyst, the total mass fraction of the active component is 40% by mass, and the atomic ratio of Pt to Ru is 2:1.

[0061] Example 3 The method in this embodiment is the same as in Example 1, except that a sulfur-modified carbon support is used. The preparation method of the sulfur-modified carbon support includes: dissolving 0.55g of sulfur in 70ml of cyclohexane to form a homogeneous solution, dispersing 9.45g of Ketjenblack ECP600JD in the solution, stirring until homogeneous, impregnating for 5 hours, and vacuum drying at 50℃ to obtain the sulfur-modified carbon support. Based on the total mass of the catalyst, the total mass fraction of the active component is 40%, and the atomic ratio of Pt to Ru is 1:1.

[0062] Example 4 The method in this embodiment is the same as in Example 1, except that in step (1), 0.845 mmol of chloroplatinic acid and 0.845 mmol of ruthenium chloride are added per gram of carbon support; and in step (2), the heat treatment temperature is 450°C to obtain the Pt1Ru1 / C catalyst. Based on the total mass of the catalyst, the total mass fraction of the active components is 20% by mass, and the atomic ratio of Pt to Ru is 1:1.

[0063] Example 5 The method in this embodiment is the same as that in embodiment 1, except that in step (1), 1.50 mmol of chloroplatinic acid and 3.74 mmol of ruthenium chloride are used per gram of carbon support, and the molar ratio of platinum source to ruthenium source is 1:2.5.

[0064] Example 6 The method in this embodiment is the same as that in embodiment 1, except that in step (2), the heat treatment temperature is 240°C.

[0065] Comparative Example 1 The method of this comparative example is the same as that of Example 1, except that the heat treatment temperature in step (2) is 600°C.

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

[0067] Comparative Example 3 The method of this comparative example is the same as that of Example 1, except that the heat treatment temperature in step (2) is 150°C.

[0068] Test Example 1 The catalysts obtained in Examples 1-6 and Comparative Examples 1-3 were subjected to XRD, XPS, and STEM tests. The XRD results are as follows: Figure 1 As shown, the characteristic peaks of Ru 3p in the XPS test are as follows: Figure 2 As shown, the results of STEM are as follows: Figures 4-7 As shown.

[0069] from Figure 1 , Figure 2 andFigure 4 It can be seen that in the XRD pattern of the catalyst of Example 1, there is a characteristic peak of Pt (111) at 2θ of 39.9°, indicating that Pt in the catalyst of Example 1 forms a nanocrystalline form. The XRD pattern does not have the characteristic peak of Ru, indicating that Ru is highly dispersed in the Pt nanocrystals in a single-atom state. In the XPS pattern, the characteristic peak of Ru 3p 3 / 2 is located at 462.6 eV, which is shifted to a higher electron volt by 1.2 eV. Ru is biased towards a higher valence state, with +2 and +4 valences, indicating that Ru is dispersed in the Pt crystal. In the STEM image, it can be seen that the active component of the catalyst of Example 1 exists in the form of nanocrystals, and the average particle size of the nanocrystals is 2.3 nm.

[0070] The XRD spectra of Examples 2-6 are the same as those of Example 1, with no Ru characteristic peaks and Pt (111) characteristic peaks located at 39.9°~40.0°. The XPS spectra of Examples 2-6 are the same as those of Example 1, with Ru 3p 3 / 2 characteristic peaks located at 461.9~463.4 eV.

[0071] In the XRD pattern of the catalyst in Comparative Example 2, the characteristic peak of Pt (111) is located at 40.8°, and the peak position has shifted, and the peak position is no longer in the position of Pt and Ru, indicating that the crystal form of Pt has changed. The STEM pattern of Comparative Example 2 is as follows... Figure 7 As shown, the catalyst exists as large particles. In Comparative Example 1, the characteristic peak of Pt(111) is located at 40.2°, forming a nanocrystalline structure, but sharp peaks appear in the XRD pattern, indicating the presence of a large number of large particles (as shown in the STEM image). Figure 6 Further analysis reveals that the Ru 3p 3 / 2 characteristic peak is located at 461.7 eV without shifting, indicating that the valence state of Ru is close to that of the commercial catalyst in Comparative Example 2, primarily being 0-valent Ru. Testing showed that the XRD pattern of the catalyst in Comparative Example 3 exhibited a rounded peak at 39.3°, indicating that the catalyst in Comparative Example 3 did not form a well-crystallized state, and the peak position of the Ru 3p 3 / 2 characteristic peak was 463.13 eV.

[0072] Test Example 2 The alkaline HER performance of the catalysts prepared in Examples 1-6 and Comparative Examples 1-3 was measured, and the results are shown in Table 1 and 2. Figure 3 As shown.

[0073] The catalyst is prepared into a uniformly dispersed slurry and coated onto a glassy carbon electrode with a diameter of 5 mm. The amount of metal catalyst on the electrode is controlled within the range of 8-10 μg. iR correction is required during calculation.

[0074] The HER test method for the hydrogen evolution reaction of water electrolysis includes: the polarization curve LSV of the catalyst is tested at 2500 rpm in 1.0 M KOH saturated with N2, with a potential range of -0.2~0.2 V (vs. RHE) and a scan rate of 0.01 V / s.

[0075] Table 1

[0076] As can be seen from the data in Table 1, the catalyst disclosed herein exhibits higher activity and stability, and a lower overpotential compared to the commercial catalyst in Comparative Example 2. A comparison of Examples 1 and 5 shows that within the preferred molar ratio of platinum to ruthenium source in this disclosure, the obtained catalyst exhibits higher activity and better stability. A comparison of Examples 1 and 6 shows that within the preferred heat treatment temperature range in this disclosure, the obtained catalyst exhibits higher activity, lower overpotential, and better stability.

[0077] 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.

[0078] 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.

[0079] 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 carbon support and an active component supported on the carbon support, the active component comprising Pt and Ru; In the XPS spectrum of the catalyst, the peak position of the 4f 7 / 2 characteristic peak of Pt is 71.4±0.3 eV, and the peak position of the 3p 3 / 2 characteristic peak of Ru is 461.9~463.4 eV; in the XRD spectrum of the catalyst, there is a (111) characteristic peak of Pt at 2θ of 39.8°~40.2°.

2. The catalyst according to claim 1, wherein, The active component includes nanocrystals, which contain Pt crystals and Ru dispersed in the Pt crystals; the average particle size of the nanocrystals is 1.2~3.5 nm.

3. The catalyst according to claim 1, wherein, The characteristic peak of Ru is not present in the XRD pattern of the catalyst.

4. The catalyst according to claim 1, wherein, Based on the total mass of the catalyst, the total mass fraction of the active component is 15-50%, and the atomic ratio of Pt to Ru is 0.5-2:

1.

5. The catalyst according to claim 1, wherein, The carbon support also includes a heteroatom-doped carbon support, wherein the heteroatoms include S and / or N elements.

6. A method for preparing a carbon-supported platinum-ruthenium catalyst, characterized in that, The method includes: (1) The platinum source, ruthenium source and carbon support are impregnated in a solvent, and the precursor is obtained after removing the solvent; (2) In a reducing atmosphere, the precursor in step (1) is heat-treated at 220~500°C.

7. The method according to claim 6, wherein, In step (1), the carbon support is conductive carbon black; the surface oxygen content of the conductive carbon black is 4% by mass or more; and the specific surface area of ​​the conductive carbon black is 200~2000 m². 2 / g; The platinum source is a platinum-containing soluble compound, including one or more of chloroplatinic acid, chloroplatinate, and tetraammineplatinum acetate; The ruthenium source is a soluble compound containing ruthenium, including one or more of ruthenium trichloride and ammonium ruthenate. The solvent includes one or more of water, alcohol solvents and ketone solvents; preferably, the solvent includes water and / or alcohol solvents, and the alcohol solvent is preferably ethanol.

8. The method according to claim 6, wherein, In step (1), the total mass of the metal source, calculated as metal elements, is 0.17~1.0g relative to 1g of the carbon support, and the molar ratio of the platinum source to the ruthenium source is 0.5~2:

1.

9. The method according to claim 6, wherein, In step (1), the soaking time is more than 10 hours, preferably 15 to 24 hours; In step (1), the solvent removal includes drying the impregnated mixture at a temperature below 100°C.

10. The method according to claim 6, wherein, In step (2), the reducing atmosphere includes hydrogen; preferably, the reducing atmosphere includes hydrogen and an inert gas, and the volume content of the hydrogen is 5-30% by volume. The inert gas is preferably nitrogen.

11. The method according to claim 6, wherein, In step (2), the heat treatment conditions include: a temperature of 260~450℃ and a time of 1~4h.

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

13. The use of the catalyst according to any one of claims 1 to 5 and claim 12 in the electrolysis of water.

14. The application according to claim 13, wherein, Application of the catalyst in the cathode of an AEM electrolyzer.

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