Carbon-supported platinum group metal catalysts, methods for producing the same, and their applications

Abstract

The present invention relates to a platinum-carbon catalyst, its manufacturing method and its application. 1s Among the spectral peaks, except for the presence of a characteristic peak between 399 eV and 400.5 eV, there is no other characteristic peak between 395 eV and 405 eV; and the support of the platinum-carbon catalyst is nitrogen-doped conductive carbon black. In the present invention, by modifying the conductive carbon black support of the platinum-carbon catalyst and controlling the doping form of the doping element, the mass-specific activity and electrochemical area of ​​the platinum-carbon catalyst can be significantly improved, and the stability and ability to inhibit carbon corrosion of the platinum-carbon catalyst can also be improved. Furthermore, the present invention provides a simple method for preparing the platinum-carbon catalyst.

Description

Detailed Description of the Invention

[0001] 〔Technical Field〕 The present invention relates to a carbon-supported platinum group metal catalyst, a method for producing the same, and its application. In particular, it relates to a carbon-supported platinum group metal catalyst for a proton membrane hydrogen fuel cell, a method for producing the same, and its application.

[0002] 〔Background Art〕 The oxygen reduction reaction (ORR) is an important reaction in the field of electrochemistry. For example, in fuel cells and metal-air batteries, the oxygen reduction reaction is a major factor affecting battery performance. Atom-doped carbon materials can be directly used as catalysts for the oxygen reduction reaction. When used as an oxygen reduction catalyst, it has been reported in the literature that elements such as nitrogen, phosphorus, boron, sulfur, fluorine, chlorine, bromine, and iodine are doped into carbon materials. Here, nitrogen has a radius close to that of carbon atoms and is easily incorporated into the carbon lattice, so it is the most commonly used doping element. There are many reports on doped carbon materials directly used as fuel cell catalysts, but there is a large difference compared with platinum-carbon catalysts.

[0003] To date, the most effective oxygen reduction catalyst is the platinum-carbon catalyst, but the platinum-carbon catalyst still has drawbacks. On the one hand, platinum resources are scarce and expensive. On the other hand, currently available commercial platinum-carbon catalysts have insufficient platinum metal dispersion, are prone to aggregation and deactivation, and the surface area of platinum is clearly reduced over time due to the dissolution and aggregation of platinum at the cathode of the hydrogen fuel cell, thereby affecting the service life of the fuel cell. The prior art mainly improves the performance of platinum-carbon catalysts by controlling the particle size, morphology and structure of platinum, as well as the specific surface area and pore structure of the carrier, but there are also reports in the literature on improving the performance of platinum-carbon catalysts by modifying the carbon carrier.

[0004] Carbon supports can improve the specific surface area of ​​the catalyst, reduce the aggregation of metal particles, and improve metal utilization. Increasing the platinum load on the carbon support can result in thinner and better-performing membrane electrodes; however, significantly increasing the platinum load can easily lead to the accumulation of platinum metal particles, causing a sharp decrease in the utilization rate of the active site. Furthermore, the platinum load in platinum-carbon catalysts used in hydrogen fuel cells is at least 20% by weight, making them extremely difficult to manufacture compared to chemically produced platinum-carbon catalysts (with a platinum load of less than 5% by weight).

[0005] The problem of platinum-carbon catalyst deactivation due to carbon corrosion in proton exchange membrane fuel cells is a subject of great interest in this field. Furthermore, platinum accelerates the rate of carbon corrosion, and the more platinum supported, the faster the carbon corrosion becomes. On the other hand, a higher number of defects in the carbon support is advantageous in increasing the amount of platinum supported, but at the same time, carbon corrosion is intensified accordingly. On the other hand, a higher degree of graphitization mitigates carbon corrosion, but it chemically inactivates the carbon support surface, making it difficult to uniformly disperse platinum on the carbon support.

[0006] The information disclosed in the aforementioned background art is solely for the purpose of deepening understanding of the background of the present invention and therefore may include information not yet known to those skilled in the art.

[0007] [Summary of the Invention] The first object of the present invention is to provide a carbon-supported platinum group metal catalyst that can significantly improve weight-specific activity and electrochemical area, especially when the amount of platinum supported is large. The second object of the present invention is to improve the overall performance of the catalyst, particularly significantly improving weight-specific activity and electrochemical area, based on the above object. The third object of the present invention is to improve the carbon corrosion resistance of the carbon-supported platinum group metal catalyst, based on the above object. The fourth object of the present invention is to provide a simple method for producing a carbon-supported platinum group metal catalyst, in addition to the above object. Other objects of the present invention will become clear from the following detailed discussion and examples of the present invention.

[0008] To achieve one or more of the above objectives, the present invention provides technical solutions in the following embodiments.

[0009] [1] XPS analysis of carbon-supported platinum group metal catalysts 1s Regarding the spectral peaks, there is a characteristic peak between 399 ev and 400.5 ev, and there are no other characteristic peaks, or substantially none, between 395 ev and 405 ev. The support for the carbon-supported platinum group metal catalyst is nitrogen-doped conductive carbon black. The carbon-supported platinum group metal catalyst is characterized by containing platinum in an amount that may be 20% to 70% by weight, preferably 40% to 70% by weight, for example, 45% to 65% by weight.

[0010] [2] The carbon-supported platinum group metal catalyst according to embodiment [1], wherein the support for the carbon-supported platinum group metal catalyst is sulfur-nitrogen-doped conductive carbon black.

[0011] [3] S in XPS analysis 2P The carbon-supported platinum group metal catalyst according to embodiment [1], characterized in that, with respect to the spectral peaks, between 160 ev and 170 ev, the peak area between 163 ev and 166 ev accounts for more than 92%, or exceeds 95%, or exceeds 98%, or a peak exists only between 163 ev and 166 ev.

[0012] [4] The carbon-supported platinum group metal catalyst according to embodiment [1], characterized in that the conductive carbon black is common conductive carbon black, super conductive carbon black, or extra conductive carbon black.

[0013] [5] The carbon-supported platinum group metal catalyst according to embodiment [1], wherein the platinum group metal is selected from platinum (Pt), palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os), and ruthenium (Ru), preferably selected from platinum, palladium, rhodium, and iridium, and more preferably selected from platinum and palladium, for example, platinum.

[0014] [6] The carbon-supported platinum group metal catalyst according to embodiment [1], characterized in that the carbon-supported platinum group metal catalyst has a resistivity of less than 10 Ω·m, preferably less than 2 Ω·m.

[0015] [7] A hydrogen fuel cell characterized in that a carbon-supported platinum group metal catalyst described in any one of embodiments [1] to

[11] is used as the anode and / or cathode of the hydrogen fuel cell.

[0016] [8] Nitrogen-doped conductive carbon black, and N in XPS analysis 1s A carbon material characterized by having a distinctive peak between 399 ev and 400.5 ev in its spectrum, but lacking any other distinctive peaks between 395 ev and 405 ev.

[0017] [9] A method for producing a carbon-supported platinum group metal catalyst according to any one of embodiments [1] to [6], comprising the following steps (1) to (3): (1) A carbon source immersion step, in which the carbon material and a nitrogen source aqueous solution are mixed (optionally, a small amount of ethanol is added as needed (for example, to disperse the carbon material in a 20% ethanol aqueous solution)), and the mixture is immersed to obtain a nitrogen source immersed carbon material; (2) The nitrogen-source immersed carbon material obtained in step (1) is heated in an inert gas at a heating rate of 8°C / min to 15°C / min to 1000°C to 1500°C, and then subjected to constant temperature treatment for 0.5 hours to 10 hours to obtain nitrogen-doped carbon material; and, (3) A platinum group metal support step, wherein the platinum group metal is supported on the nitrogen-doped carbon material obtained in step (2) above, The carbon material is preferably conductive carbon black.

[0018]

[10] The method according to embodiment [9], characterized in that the constant temperature treatment in step (2) is performed at a temperature of 1150°C to 1450°C.

[0019]

[11] The method according to embodiment [9], characterized in that the nitrogen source is aqueous ammonia or urea.

[0020]

[12] The method according to embodiment [9], characterized in that the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2 when calculated as the element of nitrogen contained.

[0021]

[13] The method according to embodiment [6], characterized in that the carbon material has an oxygen content of more than 4% by weight as determined by XPS analysis.

[0022]

[14] The method according to embodiment [9], characterized in that the step of supporting the platinum group metal includes the following (a) to (c): (a) Disperse the nitrogen-doped carbon material obtained in step (2) and the platinum group metal precursor in an aqueous phase and adjust the pH value to 8-12; (b) Adding a reducing agent for reduction; and (c) Separate the solid and subject it to post-treatment to obtain a platinum-carbon catalyst.

[0023]

[15] The platinum group metal precursor is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate. The method according to embodiment

[14] , characterized in that the concentration of the platinum group metal precursor is 0.5 mol / L to 5 mol / L.

[0024]

[16] In step (b) above, the reducing agent is selected from the group consisting of citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, and glycerol. The molar ratio of the reducing agent to the platinum is 2 to 100. The method according to embodiment

[14] , characterized in that the reduction is carried out at a temperature of 50°C to 150°C for 2 to 15 hours.

[0025] While not limited to any known theory, preferably, based on the analysis of experimental data of the characteristic peak between 163ev and 166ev (for example, as disclosed and discussed in the embodiments of the present invention), the characteristic peak between 163ev and 166ev is considered to be the characteristic peak of thiophene sulfur. In one embodiment, preferably, the characteristic peak of thiophene sulfur is considered to be bimodal.

[0026] Heteroatoms and carbon materials have various bonding modes, and various interactions exist between heteroatoms. The bonding mode between heteroatoms and carbon materials, as well as the interactions between heteroatoms, can be affected by different manufacturing methods, raw materials, and different operating steps and conditions in the doping process. As a result, the properties of heteroatoms and carbon materials differ greatly, and their functions change significantly. In this field, controlling the bonding mode between heteroatoms and carbon materials, and the interactions between heteroatoms, is a challenge when doping atoms. Research in the present invention has shown that when doping conductive carbon black, it is possible to produce carbon materials with unique properties by controlling the bonding mode between heteroatoms and conductive carbon black, as well as the interactions between heteroatoms. As a result, specific activity and electrochemical area are significantly improved, the overall performance of the catalyst is improved, the stability of specific activity and electrochemical area is improved, and the carbon corrosion resistance of carbon-supported platinum group metal catalysts is improved.

[0027] Compared to conventional technology, the present invention can achieve the following beneficial technical effects.

[0028] 1. The present invention provides a simple method for producing a type of conductive carbon black having a surface doped with atoms possessing unique properties. Compared with existing doped carbon materials, the sulfur doped on the surface of the conductive carbon black can exist only in the form of thiophene sulfur, and the nitrogen doped on the surface can exist only in the form of pyrrole nitrogen. These characteristics can significantly improve the weight-specific activity and electrochemical area of ​​carbon-supported platinum group metal catalysts. Furthermore, the surface of the conductive carbon black can be doped with phosphorus and / or boron, where the phosphorus doped on the surface has a characteristic peak only between 132.5 eV and 134.5 eV, and the boron doped on the surface has a characteristic peak only between 189 eV and 191 eV. As a result, the overall performance of the carbon-supported platinum group metal catalyst can be improved, particularly the weight-specific activity and the stability of the electrochemical area. Furthermore, the surface of the conductive carbon black can be doped with multiple (e.g., 3 or 4) heteroatoms, which is advantageous for improving the carbon corrosion resistance of the carbon-supported platinum group metal catalyst.

[0029] 2. The doped conductive carbon black of the present invention is suitable for the production of carbon-supported platinum group metal catalysts with a high platinum support, and when the platinum group metal support reaches 70% by weight, it exhibits excellent overall catalytic performance and carbon corrosion resistance.

[0030] 3. In practical applications of hydrogen fuel cells, the amount of platinum supported in carbon-supported platinum group metal catalysts is typically 20% by weight or more, and it is extremely difficult to produce catalysts with a high amount of platinum group metals that exhibit excellent performance. Chemical reduction is a simple method, but the utilization rate of platinum group metals is low, and the catalytic activity is relatively low. However, by using the doped conductive carbon black produced by the present invention as a support and employing a chemical reduction method in the aqueous phase, it is possible to easily produce catalysts with a high amount of platinum that have both good weight-specific activity and stability.

[0031] The present invention provides the following exemplary embodiments, or combinations thereof, as examples.

[0032] A first set of exemplary embodiments of the present invention include the following:

[0033] 1. N in XPS analysis 1s A platinum-carbon catalyst characterized by having a distinctive peak between 399 eV and 400.5 eV in its spectrum, but lacking any other distinctive peaks between 395 eV and 405 eV.

[0034] 2. The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that the platinum contains platinum in an amount of 20% to 70% by weight, preferably 40% to 70% by weight, based on the weight of the catalyst.

[0035] 3. The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that the platinum-carbon catalyst has a resistivity of less than 10 Ω·m.

[0036] 4. The carbon-supported platinum group metal catalyst according to exemplary embodiment 1, characterized in that the support of the carbon-supported platinum group metal catalyst is nitrogen-doped conductive carbon black, nitrogen-doped graphene, or nitrogen-doped carbon nanotubes.

[0037] 5. The platinum-carbon catalyst according to exemplary embodiment 4, characterized in that the conductive carbon black is EC-300J, EC-600JD, ECP600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0038] 6. A method for producing a carbon-supported platinum group metal catalyst, comprising the following (1) to (3): (1) A carbon source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) The nitrogen-source immersed carbon material obtained in step (1) is heated in an inert gas at a heating rate of 8°C / min to 15°C / min to 1000°C to 1500°C, and then subjected to constant temperature treatment for 0.5 hours to 10 hours to obtain nitrogen-doped carbon material; and, (3) Platinum support step, wherein a platinum group metal is supported on the nitrogen-doped carbon material obtained in step (2) above.

[0039] 7. The method according to exemplary embodiment 6, characterized in that the constant temperature treatment in step (2) is performed at a temperature of 1150°C to 1450°C.

[0040] 8. The method according to exemplary embodiment 6, characterized in that the nitrogen source is aqueous ammonia or urea.

[0041] 9. The method according to exemplary embodiment 6, characterized in that the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, calculated as the element of nitrogen contained.

[0042] 10. The method according to exemplary embodiment 6, characterized in that the carbon material is conductive carbon black, graphene, or carbon nanotubes.

[0043] 11. The method according to exemplary embodiment 10, characterized in that the conductive carbon black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0044] 12. The method according to exemplary embodiment 6, characterized in that the carbon material has an oxygen content of more than 4% by weight as determined by XPS analysis.

[0045] 13. The method according to exemplary embodiment 6, characterized in that the carbon material has a resistivity of less than 10 Ω·m.

[0046] 14. The carbon material has a specific surface area of ​​10 m². 2 / g~2000m 2 The method according to exemplary embodiment 6, characterized in that it is / g.

[0047] 15. The method according to exemplary embodiment 6, characterized in that the platinum loading step includes the following (a) to (c): (a) Disperse the nitrogen-doped carbon material obtained in step (2) and the platinum precursor in an aqueous phase and adjust the pH value to 8-12; (b) Adding a reducing agent for reduction; and (c) Separate the solid and subject it to post-treatment to obtain a platinum-carbon catalyst.

[0048] 16. The platinum group metal precursor is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate. The method according to exemplary embodiment 15, characterized in that the concentration of the platinum group metal precursor is 0.5 mol / L to 5 mol / L.

[0049] 17. In step (b) above, the reducing agent is selected from the group consisting of citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, and glycerol. The molar ratio of the reducing agent to the platinum is 2 to 100. The method according to exemplary embodiment 15, characterized in that the reduction is carried out at a temperature of 50°C to 150°C for 2 to 15 hours.

[0050] 18. A platinum-carbon catalyst characterized in that the catalyst is manufactured by the method described in any one of the exemplary embodiments 6 to 17.

[0051] 19. A hydrogen fuel cell characterized in that the platinum-carbon catalyst described in any one of the exemplary embodiments 1 to 5 and 18 is used as the anode and / or cathode of the hydrogen fuel cell.

[0052] A second set of exemplary embodiments of the present invention include the following:

[0053] 1. The material comprises a carbon carrier and a platinum metal supported on the carbon carrier, wherein the carbon carrier is a sulfur-nitrogen-doped carbon material. S in XPS analysis 2P A platinum-carbon catalyst characterized by having a distinctive peak in its spectrum between 163ev and 166ev, specifically between 160ev and 170ev.

[0054] 2. N in XPS analysis 1s The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that, regarding spectral peaks, it has a characteristic peak between 399 ev and 400.5 ev, but does not have any other characteristic peaks between 390 ev and 410 ev.

[0055] 3. The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that platinum is included in an amount of 20% to 70% by weight, preferably 40% to 70% by weight, based on the weight of the catalyst.

[0056] The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that the distinctive peaks between 4.163ev and 166ev are located at 163.4±0.5ev and 164.7±0.5ev.

[0057] 5. The platinum-carbon catalyst according to exemplary embodiment 1, characterized in that the sulfur-nitrogen-doped carbon material is sulfur-nitrogen-doped conductive carbon black, sulfur-nitrogen-doped graphene, or sulfur-nitrogen-doped carbon nanotubes.

[0058] 6. A method for producing a platinum-carbon catalyst, comprising (1) and (2) below: (1) Process for producing sulfur-nitrogen-doped carbon material; (2) A step of supporting platinum using the sulfur-nitrogen-doped carbon material obtained in step (1) as a support; Here, the step (1) includes an operation of doping sulfur and an operation of doping nitrogen. The operation of doping sulfur includes placing the carbon material in an inert gas containing thiophene and treating it at 1000°C to 1500°C for 0.5 hours to 10 hours. The operation of doping nitrogen is performed before, after, or simultaneously with the operation of doping sulfur.

[0059] 7. The method according to exemplary embodiment 6, wherein the weight ratio of the carbon material to thiophene is 20:1 to 2:1, calculated as the element of sulfur contained in thiophene.

[0060] 8. The method according to exemplary embodiment 6, wherein the operation of doping sulfur is performed at a temperature of 1150°C to 1450°C.

[0061] 9. The method according to exemplary embodiment 6, wherein the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, calculated as the element of nitrogen contained in the nitrogen source.

[0062] 10. The method according to exemplary embodiment 6, wherein the carbon material is conductive carbon black, graphene, or carbon nanotube.

[0063] 11. The method according to exemplary embodiment 6, wherein the carbon material has a resistivity of less than 10 Ω·m and a specific surface area of 10 m 2 / g to 2000 m 2 / g.

[0064] 12. The method according to exemplary embodiment 6, wherein the step of supporting platinum includes the following (a) to (c): (a) Disperse the nitrogen-doped carbon material obtained in (1) and the platinum group metal precursor in an aqueous phase and adjust the pH value to 8 to 12; (b) Add a reducing agent for reduction; and (c) Separating the solid and subjecting it to post-treatment to obtain the platinum-carbon catalyst.

[0065] In 13.(a), the platinum precursor is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate. The method according to exemplary embodiment 12, characterized in that the concentration of the platinum precursor is 0.5 mol / L to 5 mol / L.

[0066] 14. In step (b), the reducing agent is selected from the group consisting of citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, or glycerol. The molar ratio of the reducing agent to the platinum is 2 to 100. The method according to exemplary embodiment 12, characterized in that the reduction is carried out at a temperature of 60°C to 90°C for 4 to 15 hours.

[0067] 15. A method for producing a platinum-carbon catalyst, comprising the following (1) to (3): (1) A carbon source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) The nitrogen source immersion carbon material obtained in (1) is treated in thiophene containing an inert gas at 1000°C to 1500°C for 0.5 to 10 hours to obtain a nitrogen-doped carbon material; and, (3) A step of supporting platinum using the sulfur-nitrogen-doped carbon material obtained in (2) as a support.

[0068] 16. A platinum-carbon catalyst characterized in that the catalyst is manufactured by the method described in any one of the exemplary embodiments 6 to 15.

[0069] 17. A hydrogen fuel cell characterized by using a platinum-carbon catalyst described in any one of exemplary embodiments 1 to 5 and 16 as the anode and / or cathode of the hydrogen fuel cell.

[0070] A third set of exemplary embodiments of the present invention include the following:

[0071] 1. N in XPS analysis 1s A nitrogen-doped carbon material characterized by having a distinctive peak between 399 ev and 400.5 ev in its spectrum, but lacking any other distinctive peaks between 395 ev and 405 ev.

[0072] 2. The nitrogen-doped carbon material according to exemplary embodiment 1, characterized in that the nitrogen-doped carbon material has a nitrogen content of 0.1% to 10% by weight as determined by XPS analysis.

[0073] 3. The nitrogen-doped carbon material according to exemplary embodiment 1, characterized in that the nitrogen-doped carbon material has an oxygen content of more than 4% by weight as determined by XPS analysis.

[0074] 4. The nitrogen-doped carbon material according to exemplary embodiment 1, characterized in that the carbon material has a resistivity of less than 10 Ω·m.

[0075] 5. The nitrogen-doped carbon material has a specific surface area of ​​10 m². 2 / g~2000m 2 A nitrogen-doped carbon material according to exemplary embodiment 1, characterized in that it is / g.

[0076] 6. The nitrogen-doped carbon material according to exemplary embodiment 1, characterized in that the nitrogen-doped carbon material is nitrogen-doped conductive carbon black, nitrogen-doped graphene, or nitrogen-doped carbon nanotubes.

[0077] 7. The nitrogen-doped carbon material according to exemplary embodiment 6, characterized in that the conductive carbon black is EC-300J, EC-600JD, ECP600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0078] 8. The carbon support is nitrogen-doped conductive carbon black, and N is found in XPS analysis. 1s Regarding the spectral peaks, there is a characteristic peak between 399 ev and 400.5 ev, but no other characteristic peaks between 395 ev and 405 ev. XPS analysis revealed that the oxygen content was 4% to 15% by weight, and the nitrogen content was 0.2% to 5% by weight, and Specific surface area is 200 m 2 / g~2000m 2 A carbon support for platinum-carbon catalysts, characterized by having a density of / g.

[0079] 9. The carbon carrier according to exemplary embodiment 8, characterized in that the conductive carbon black is EC-300J, EC-600JD, ECP600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0080] 10. A method for producing nitrogen-doped carbon material, comprising (1) and (2) below: (1) A carbon source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) A process for producing nitrogen-doped carbon material, in which the nitrogen-source immersed carbon material obtained in (1) is heated to 1000°C to 1500°C in an inert gas at a heating rate of 8°C / min to 15°C / min, and then subjected to constant temperature treatment for 0.5 hours to 10 hours.

[0081] The method according to exemplary embodiment 10, characterized in that the constant temperature treatment in 11.(2) is performed at a temperature of 1150°C to 1450°C.

[0082] 12. The method according to exemplary embodiment 10, characterized in that the nitrogen source is aqueous ammonia or urea.

[0083] 13. The method according to exemplary embodiment 10, characterized in that the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, preferably 25:1 to 1:1.5, calculated as the elemental nitrogen contained in the nitrogen source.

[0084] 14. Use of a nitrogen-doped carbon material or carbon support described in any one of Embodiments 1 to 9 as an electrode material in electrochemistry.

[0085] 15. A fuel cell characterized by using a nitrogen-doped carbon material or carbon carrier described in any one of the exemplary embodiments 1 to 9.

[0086] 16. The fuel cell according to exemplary embodiment 15, characterized in that the fuel cell is a hydrogen fuel cell.

[0087] 17. A metal-air battery characterized by using a nitrogen-doped carbon material or carbon carrier described in any one of the exemplary embodiments 1 to 9.

[0088] 18. The metal-air battery according to exemplary embodiment 17, characterized in that the metal-air battery is a lithium-air battery.

[0089] Further features and advantages of the present invention will be described below with reference to embodiments.

[0090] [Brief explanation of the drawing] [Embodiment I] Figure I-1 shows the XPS spectrum of the nitrogen-doped carbon support of Example 1.

[0091] Figure I-2 shows the XPS spectrum of the nitrogen-doped carbon support of Example 3.

[0092] Figure I-3 shows the XPS spectrum of the platinum-carbon catalyst of Example 5.

[0093] Figure I-4 shows the polarization curve of the platinum-carbon catalyst of Example 5 around 5000 cycles.

[0094] Figure I-5 shows the XPS spectrum of the platinum-carbon catalyst of Example 6.

[0095] Figure I-6 shows the XPS spectrum of the platinum-carbon catalyst of Example 7.

[0096] Figure I-7 shows the XPS spectrum of the platinum-carbon catalyst of Example 8.

[0097] Figure I-8 shows the polarization curve of the platinum-carbon catalyst of Comparative Example 3 around 5000 cycles.

[0098] [Embodiment II] Figure II-1 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-1.

[0099] Figure II-2 shows the XPS spectrum of nitrogen in the sulfur-nitrogen-doped carbon material of Example II-1.

[0100] Figure II-3 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-2.

[0101] Figure II-4 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-3.

[0102] Figure II-5 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-4.

[0103] Figure II-6 shows the TEM pattern of the platinum-carbon catalyst of Example II-5.

[0104] Figure II-7 shows the polarization curve of the platinum-carbon catalyst of Example II-5.

[0105] Figure II-8 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-5.

[0106] Figure II-9 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-5.

[0107] Figure II-10 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-7.

[0108] Figure II-11 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-7.

[0109] Figure II-12 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-1.

[0110] Figure II-13 shows the TEM pattern of the platinum-carbon catalyst of Comparative Example II-1.

[0111] Figure II-14 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-1.

[0112] Figure II-15 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-2.

[0113] Figure II-16 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-3.

[0114] [Modes for carrying out the invention] The embodiments of the present invention will be described below, but please understand that the scope of protection of the present invention is not limited to these embodiments or the principled description thereof, and the scope of protection is defined by the claims.

[0115] In the context of this Spectrum, any features or technical means not specifically discussed herein shall be understood in the sense known in the art without any substantial modification unless otherwise indicated. Furthermore, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the resulting technical solution or technical idea shall be considered part of the original disclosure or description, but shall not be considered new content not disclosed or anticipated herein unless a person skilled in the art believes the combination is clearly unreasonable.

[0116] All features disclosed herein can be combined in any way and should be understood as disclosures of the present invention unless a person skilled in the art would consider such combinations to be obviously unreasonable. The numerical points disclosed herein include not only the individual numbers specifically mentioned in the examples but also the endpoints of each numerical range. Any range formed by a combination of such numerical points should be considered disclosed or described herein.

[0117] Technical and scientific terms used herein are defined by the definitions specifically given herein, but other terms for which no definition is given shall be understood according to their common meaning in the art.

[0118] The “doped elements” in this invention include or are selected from nitrogen, phosphorus, boron, sulfur, fluorine, chlorine, bromine, and iodine.

[0119] In the present invention, an element “doped” material means that one or more elements specifically mentioned are doped into the material, but the material may be doped with one or more other elements specifically mentioned (in particular elements commonly used in the art).

[0120] In the present invention, the element in which a material is “doped” means that one or more elements specifically mentioned are doped into the material; however, in one embodiment, the material may be doped with elements other than the one or more elements specifically mentioned, and preferably the material does not contain any other doping elements other than the one or more elements specifically mentioned.

[0121] In this invention, unless otherwise identifiable as “carbon material containing doped elements” according to the context or its own definition, other references to “carbon material” refer to carbon material that does not contain doped elements. The same applies to the subconcepts of carbon material.

[0122] In the present invention, "carbon black" and "carbon black" are interchangeable terms used to substitute for each other. In the present invention, graphene, carbon nanotubes, and conductive carbon black, which can be used in the carbon materials of the present invention, each have concepts that are well known in the art and belong to different concepts from each other. However, according to the present invention, a carbon material may contain one or more other carbon materials in low amounts, as long as it remains within the range of carbon materials well recognized by those skilled in the art. For example, "graphene" may contain trace amounts (e.g., less than 1% by weight or less than 0.1% by weight) of conductive carbon black and / or carbon nanotubes for various reasons. Preferably, for example, for the purposes of the present invention, conductive carbon black contains less than 5% by weight, preferably less than 2% by weight of graphene and / or carbon nanotubes.

[0123] In this invention, "inert gas" refers to a gas that does not significantly affect the properties of the carbon material doped during the manufacturing process of this invention. The same applies to the sub-concepts of carbon material.

[0124] A numerical range as defined in this invention includes the endpoints of the numerical range. A “range” disclosed herein is given as a lower and upper limit (e.g., one or more lower limits with one or more upper limits). A given range may be defined by selecting lower and upper limits that define the boundaries of a given range. All ranges defined in this manner are encompassed and can be combined. That is, any lower limit can be combined with any upper limit to form a range. For example, if the ranges 60-110 and 80-120 are enumerated for a particular parameter, it is understood that the ranges 60-120 and 80-110 are also intended. Furthermore, if the enumerated lower limits are 1 and 2 and the enumerated upper limits are 3, 4 and 5, then 1-3, 1-4, 1-5, 2-3, 2-4, and 2-5 are all intended.

[0125] In the present invention, unless otherwise indicated, the terms “comprising,” “including,” “containing,” “having,” and similar terms are intended to be broad in definition but should also be interpreted as encompassing narrow in definition. For example, “comprising” means that other elements not enumerated may also be included, but it also means disclosure of only the enumerated elements. Furthermore, as used herein, “comprising / including” is intended to identify the presence of a feature, integer, process, or component mentioned, but does not exclude the presence or addition of one or more other features, integers, processes, components, or groups thereof. Furthermore, the term “comprising” is intended to include embodiments encompassed by the terms “substantially consisting of” and “consisting of.” Similarly, the term “substantially consisting of” is intended to include embodiments encompassed by the term “consisting of.”

[0126] In the present invention, all embodiments and preferred embodiments referred to herein can be combined with each other to form new technical solutions unless otherwise indicated. In particular, with respect to embodiments I and II of the present invention, for example, the technical features and technical solutions referred to herein can be combined internally and with each other, insofar as the combination does not contradict the spirit of the invention.

[0127] In the present invention, all technical features and preferred technical features referred to herein can be combined with each other to form new technical solutions, unless otherwise indicated.

[0128] In this invention, unless otherwise evident from the context or its own definition, all references to "pore volume" refer to the total pore volume of single-site adsorption at maximum P / P0.

[0129] In the present invention, "substantially no other characteristic peaks between 395ev and 405ev" means that, with the exception of the characteristic peak between 399ev and 400.5ev (for example, preferably the characteristic peak of pyrroleous nitrogen), the peak area of ​​each other characteristic peak is less than 10%, preferably less than 5%.

[0130] [Embodiment I] Embodiment I of the present invention is an N in XPS analysis 1s The present invention provides a platinum-carbon catalyst that exhibits a characteristic peak between 399 eV and 400.5 eV in its spectrum, but lacks any other characteristic peaks between 395 eV and 405 eV.

[0131] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention does not contain any doping elements other than nitrogen.

[0132] In one embodiment of Embodiment I, the platinum group metal is platinum.

[0133] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention does not contain any metal elements other than platinum.

[0134] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention contains platinum in an amount of 0.1% to 80% by weight, preferably 20% to 70% by weight, and more preferably 40% to 70% by weight, based on the weight of the catalyst.

[0135] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention has a resistivity of less than 10.0 Ω·m, preferably less than 2 Ω·m.

[0136] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention has a specific surface area of ​​80 m². 2 / g~1500m 2 / g, preferably 100m 2 / g~200m 2 It is / g.

[0137] In one embodiment of Embodiment I, the support for the carbon-supported platinum group metal catalyst according to the present invention is nitrogen-doped conductive carbon black, nitrogen-doped graphene, or nitrogen-doped carbon nanotubes.

[0138] In one embodiment of Embodiment I, the conductive carbon black in the carbon-supported platinum group metal catalyst according to the present invention may be one or more of the superconducting carbon blacks from the Ketjen black series, the conductive carbon blacks from the Cabot series, and the conductive carbon blacks from the EVONIK-DEGUSSA series, preferably one or more of Ketjen black EC-300J, Ketjen black EC-600JD, Ketjen black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0139] Embodiment I of the present invention also provides a method for producing a carbon-supported platinum group metal catalyst, comprising the following (1) to (3): (1) A carbon source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) A process for producing nitrogen-doped carbon material, wherein the nitrogen-source immersed carbon material obtained in step (1) is heated in an inert gas at a heating rate of 8°C / min to 15°C / min to 1000°C to 1500°C, and then subjected to constant temperature treatment for 0.5 hours to 10 hours; and (3) A platinum group metal (e.g., platinum) support step, wherein the nitrogen-doped carbon material obtained in step (2) is used as a support to support a platinum group metal (e.g., platinum).

[0140] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the constant temperature treatment can be carried out at a temperature of 1000°C to 1500°C, preferably 1150°C to 1450°C, for 0.5 hours to 10 hours, preferably 1 hour to 5 hours, and more preferably 2 hours to 4 hours.

[0141] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the nitrogen source may be aqueous ammonia and / or urea.

[0142] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, preferably 25:1 to 1:1.5, calculated as the element of nitrogen contained in the nitrogen source.

[0143] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the carbon material may be conductive carbon black, graphene, or carbon nanotubes.

[0144] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the conductive carbon black may be common conductive carbon black, super conductive carbon black, or extra conductive carbon black. For example, the conductive carbon black may be one or more of the super conductive carbon blacks of the Ketjen black series, the conductive carbon blacks of the Cabot series, and the conductive carbon blacks of the EVONIK-DEGUSSA series, preferably one or more of Ketjen black EC-300J, Ketjen black EC-600JD, Ketjen black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2.

[0145] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the method for producing conductive carbon black and the raw materials are not limited. As the conductive carbon black, acetylene black, furnace carbon black, etc., can be used.

[0146] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I, conductive carbon black I D / I G The value is usually 0.8 to 5, preferably 1 to 4. For the Raman spectrum, 1320 cm⁻¹ -1 The nearby peak is Peak D, at 1580cm. -1 The nearby peak is Peak G, and I D represents the intensity of the D peak, and I G This represents the intensity of the G peak.

[0147] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the graphene or carbon nanotube may be unoxidized graphene or carbon nanotube, or it may be oxidized graphene or carbon nanotube.

[0148] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment I of the present invention, the carbon material has an oxygen content of 4% by weight or more, preferably 4% to 15% by weight, as determined by XPS analysis.

[0149] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the carbon material has a resistivity of less than 10 Ω·m, preferably less than 5 Ω·m, and more preferably less than 2 Ω·m.

[0150] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the carbon material in step (1) has a specific surface area of ​​10 m². 2 / g~2000m 2 The concentration is per gram, and the pore volume is between 0.2 mL / g and 6.0 mL / g.

[0151] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, in an embodiment for producing a nitrogen-doped carbon material, a carbon material and an aqueous solution of a nitrogen source are mixed, immersed (generally for 12 to 72 hours), dried (generally at 70°C to 120°C), then placed in a tubular furnace and heated (at an arbitrary heating rate of 8°C / min to 15°C / min), then treated at a high temperature (1000°C to 1500°C, preferably 1150°C to 1450°C) for a certain period of time (which may be 0.5 to 10 hours, generally 1 to 5 hours), thereby obtaining a nitrogen-doped carbon material.

[0152] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment I of the present invention, the nitrogen-doped carbon material produced in step (2) can be easily dispersed in the aqueous phase. However, it is difficult to directly disperse some carbon materials, such as Ketjen black, in the aqueous phase.

[0153] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the step of supporting a platinum group metal (e.g., platinum) includes the following (a) to (c): (a) Disperse the nitrogen-doped carbon material obtained in step (2) and a platinum group metal precursor (e.g., a platinum precursor) in an aqueous phase and adjust the pH to 8-12 (preferably, adjust the pH to 10±0.5); (b) Adding a reducing agent for reduction; and (c) Separate the solid and subject it to post-processing to obtain a carbon-supported platinum group metal (e.g., carbon-supported platinum) catalyst.

[0154] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the platinum group metal precursor (e.g., platinum precursor) is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate, and the concentration of the platinum group metal precursor (e.g., platinum precursor) is 0.5 mol / L to 5 mol / L.

[0155] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, in step (a), the pH of the aqueous phase is adjusted using an aqueous solution of sodium carbonate, an aqueous solution of potassium carbonate, an aqueous solution of potassium hydroxide, an aqueous solution of sodium hydroxide, or aqueous ammonia.

[0156] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, in step (b), the reducing agent is one or more selected from citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, and glycerol.

[0157] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, in step (b), the molar ratio of the reducing agent to the platinum is 2 to 100.

[0158] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, in step (b), the reduction is carried out at a temperature of 50°C to 150°C, preferably 60°C to 90°C, for 4 to 15 hours, preferably 8 to 12 hours.

[0159] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment I of the present invention, the post-treatment includes washing, filtration, and drying.

[0160] Embodiment I of the present invention also provides a carbon-supported platinum group metal catalyst produced by the method of any embodiment of Embodiment I of the present invention described above.

[0161] Embodiment I of the present invention also provides a hydrogen fuel cell that uses a carbon-supported platinum group metal catalyst according to any embodiment of Embodiment I of the present invention described above in the anode and / or cathode of the hydrogen fuel cell.

[0162] This invention provides a platinum-carbon electrode catalyst for anodic hydrogen oxidation or cathode oxygen reduction reactions in hydrogen fuel cells by employing a simple method of doping nitrogen on the surface of a carbon material in the form of pyrrole nitrogen. This results in a higher half-wave potential compared to conventional catalysts having the same carbon material and platinum load, and significantly improves the catalyst's ECSA, as well as its weight-specific activity and stability.

[0163] In one embodiment of Embodiment I, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some embodiments, ECSA is 55m 2 g -1 -Pt or greater, for example, 55m 2 g -1 -Pt~140m 2 g -1 -This is within the range of Pt.

[0164] In one embodiment of Embodiment I, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some embodiments, the reduction in weight specific activity after 5000 cycles is less than 10%.

[0165] In one embodiment of Embodiment I, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some embodiments the half-wave potential is greater than 0.88 V, for example, 0.88 V to 0.92 V.

[0166] In one embodiment of Embodiment I, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some embodiments, the weight specific activity is 0.11 A mg -1 - It is greater than Pt, for example 0.11Amg -1 -Pt~0.44Amg -1 -Pt

[0167] In one embodiment of Embodiment I, the carbon-supported platinum group metal catalyst according to the present invention is a platinum-carbon catalyst.

[0168] [Embodiment II] Embodiment II of the present invention comprises a carbon carrier and a platinum metal supported on the carbon carrier, wherein the carbon carrier is a sulfur-nitrogen-doped carbon material, and XPS analysis shows S 2P Regarding spectral peaks, the present invention provides a carbon-supported platinum group metal catalyst in which characteristic peaks are present only between 163ev and 166ev, and between 160ev and 170ev.

[0169] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst according to the present invention (e.g., platinum-carbon catalyst) does not contain doping elements other than sulfur and nitrogen.

[0170] In one embodiment of Embodiment II, the platinum group metal is platinum.

[0171] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention does not contain any metal elements other than platinum.

[0172] In one embodiment of Embodiment II, XPS analysis of the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention shows that a characteristic peak exists only between 163 eV and 166 eV. 2P It shows spectral peaks.

[0173] In one embodiment of Embodiment II, XPS analysis of the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention does not show a characteristic peak between 166 eV and 170 eV.

[0174] In one embodiment of Embodiment II, XPS analysis of the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention shows a characteristic peak between 399 eV and 400.5 eV, but no other characteristic peak between 390 eV and 410 eV. 1s It shows spectral peaks.

[0175] In one embodiment of Embodiment II, XPS analysis of the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention shows one or two characteristic peaks between 399 ev and 400.5 ev. 1s It shows spectral peaks.

[0176] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst according to the present invention (e.g., platinum-carbon catalyst) contains platinum in an amount of 0.1% to 80% by weight, preferably 20% to 70% by weight, and more preferably 40% to 70% by weight, based on the weight of the catalyst.

[0177] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst according to the present invention (e.g., platinum-carbon catalyst) has a resistivity of less than 10.0 Ω·m, preferably less than 2.0 Ω·m.

[0178] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention has a specific surface area of ​​80 m². 2 / g~1500m 2 / g, preferably 100m 2 / g~200m 2 It is / g.

[0179] In one embodiment of Embodiment II, for a carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention, the sulfur-nitrogen-doped carbon material is sulfur-nitrogen-doped conductive carbon black, sulfur-nitrogen-doped graphene, or sulfur-nitrogen-doped carbon nanotubes. The conductive carbon black may be one or more of the superconducting carbon blacks of the Ketjen black series, the conductive carbon blacks of the Cabot series, and the conductive carbon blacks of the EVONIK-DEGUSSA series, preferably one or more of Ketjen black EC-300J, Ketjen black EC-600JD, Ketjen black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2. The graphene or carbon nanotubes may be oxidized graphene or carbon nanotubes, or unoxidized graphene or carbon nanotubes.

[0180] In one embodiment of Embodiment II, for the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention, the characteristic peak between 163ev and 166ev is bimodal, and in some Embodiment II-, the two peaks are located at 163.4±0.5ev and 164.7±0.5ev, respectively.

[0181] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention contains sulfur in a content of 0.2% to 3% by weight and nitrogen in a content of 0.1% to 5% by weight, based on the weight of the support of the carbon-supported platinum group metal catalyst as measured by XPS testing.

[0182] Embodiment II of the present invention also provides a method for producing a carbon-supported platinum group metal catalyst (e.g., a platinum-carbon catalyst), comprising the following (1) and (2): (1) Process for producing sulfur-nitrogen-doped carbon material; (2) A step of supporting a platinum group metal (e.g., platinum) using the sulfur-nitrogen-doped carbon material obtained in step (1) as a support; Here, step (1) includes the operation of doping with sulfur and the operation of doping with nitrogen, The sulfur-doping operation includes placing the carbon material in an inert gas containing thiophene and treating it at 1000°C to 1500°C (preferably constant temperature treatment) for 0.5 to 10 hours. The nitrogen doping operation is performed before, after, or simultaneously with the sulfur doping operation.

[0183] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, in the sulfur doping operation, the temperature is raised at a rate of 8°C / min or higher (which may be 8°C / min to 15°C / min) as needed.

[0184] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, any conventionally known nitrogen doping method can be used when the nitrogen doping operation is performed before, after, or simultaneously with the sulfur doping operation. In one embodiment, the nitrogen doping operation is performed before the sulfur doping operation, in which the carbon material and the nitrogen source are mixed and treated in an inert gas for 0.5 to 10 hours at 300°C to 1500°C (preferably treated at a constant temperature). In another embodiment, the nitrogen doping operation is performed after the sulfur doping operation, in which the sulfur-doped carbon material and the nitrogen source are mixed and treated in an inert gas for 0.5 to 10 hours at 300°C to 1500°C (preferably treated at a constant temperature).

[0185] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the nitrogen doping operation may be performed simultaneously with the sulfur doping operation, and the same operating conditions as for the sulfur doping operation may be used. In one embodiment, the carbon material is mixed with a nitrogen source and then subjected to the nitrogen doping operation and the sulfur doping operation simultaneously under the same conditions as for the sulfur doping operation.

[0186] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the weight ratio of the carbon material to the thiophene is 20:1 to 2:1, preferably 10:1 to 4:1, and more preferably 8:1 to 4:1, calculated as the sulfur element contained in the thiophene.

[0187] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the sulfur doping operation is preferably carried out at a temperature of 1100°C to 1400°C, more preferably 1200°C to 1400°C.

[0188] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the sulfur doping operation and the nitrogen doping operation are each carried out for 1 to 5 hours, preferably 2 to 4 hours.

[0189] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, preferably 25:1 to 1:1.5, calculated as the element of nitrogen contained in the nitrogen source.

[0190] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, XPS analysis of the sulfur-nitrogen-doped carbon material according to the present invention shows S between 160 ev and 170 ev. 2P Regarding the spectral peaks, we show that a characteristic peak exists only between 163 ev and 166 ev.

[0191] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the characteristic peak between 163ev and 166ev of the carbon-supported platinum group metal catalyst according to the present invention is a bimodal peak, and in some Examples II-, the two peaks are located at 163.7±0.5ev and 165.0±0.5ev, respectively.

[0192] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the carbon material may be conductive carbon black, graphene, or carbon nanotubes. The conductive carbon black may be general conductive carbon black, superconducting carbon black, or extraconducting carbon black. For example, the conductive carbon black may be one or more of the superconducting carbon blacks of the Ketjen black series, the conductive carbon blacks of the Cabot series, and the conductive carbon blacks of the EVONIK-DEGUSSA series, preferably one or more of Ketjen black EC-300J, Ketjen black EC-600JD, Ketjen black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6, or HIBLAXK 40B2. The graphene or carbon nanotubes may be oxidized graphene or carbon nanotubes, or unoxidized graphene or carbon nanotubes.

[0193] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the method for producing conductive carbon black and the raw materials are not limited. As the conductive carbon black, acetylene black, furnace carbon black, etc., can be used.

[0194] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II, the carbon material is typically I D / I G The value is between 0.8 and 5, preferably between 1 and 4. For the Raman spectrum, 1320 cm⁻¹ -1 The nearby peak is Peak D, at 1580cm. -1 The nearby peak is Peak G, and I D represents the intensity of the D peak, and I G This represents the intensity of the G peak.

[0195] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the carbon material may have a resistivity of less than 10 Ω·m, preferably less than 5 Ω·m, and more preferably less than 2 Ω·m.

[0196] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the carbon material has an oxygen content of more than 2% by weight, for example, 2% to 15% by weight, preferably 2.5% to 12% by weight, as determined by XPS analysis.

[0197] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the specific surface area and pore volume of the carbon material can vary over a wide range. Typically, the specific surface area is 10 m². 2 / g~2000m 2 The pore volume is 0.02 mL / g to 6 mL / g.

[0198] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in one embodiment, the carbon material in step (1) is 200 m 2 / g~2000m 2 This is a conductive carbon black with a specific surface area of ​​1 / g.

[0199] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the inert gas may be nitrogen gas or argon gas.

[0200] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in one embodiment of the sulfur-doping operation, a carbon material is placed in a tubular furnace, a carrier gas containing thiophene is introduced, the tubular furnace is heated to 1000°C to 1500°C at a rate of 8°C / min to 15°C / min, and then subjected to constant temperature treatment for 0.5 hours to 10 hours.

[0201] The carrier gas can be nitrogen gas or argon gas.

[0202] The carrier gas may contain thiophene in an amount of 0.1% to 5.0% by volume.

[0203] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the step of supporting a platinum group metal (e.g., platinum) includes the following (a) to (c): (a) Disperse the sulfur-nitrogen-doped carbon material and platinum group metal precursor obtained in step (1) in an aqueous phase and adjust the pH to 8-12 (preferably, adjust the pH to 10 ± 0.5); (b) Adding a reducing agent for reduction; and (c) Separate the solid and subject it to post-processing to obtain a carbon-supported platinum group metal (e.g., carbon-supported platinum) catalyst.

[0204] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in step (a), the platinum group metal precursor (e.g., platinum precursor) is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate, and the concentration of the platinum group metal precursor (e.g., platinum precursor) is 0.5 mol / L to 5 mol / L.

[0205] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in step (a), the pH of the aqueous phase is adjusted using an aqueous sodium carbonate solution, an aqueous potassium hydroxide solution, an aqueous sodium hydroxide solution, or aqueous ammonia.

[0206] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in step (b), the reducing agent is one or more selected from citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, and glycerin.

[0207] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in step (b), the molar ratio of the reducing agent to platinum is 2 to 100.

[0208] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, in step (b), the reduction is carried out at a temperature of 50°C to 150°C, preferably 60°C to 90°C, for 4 to 15 hours, preferably 8 to 12 hours.

[0209] According to the method for producing a carbon-supported platinum group metal catalyst according to Embodiment II of the present invention, the sulfur-nitrogen-doped carbon material produced in step (1) can be easily dispersed in the aqueous phase. However, it is difficult to directly disperse some carbon materials, such as Ketjen black, in the aqueous phase.

[0210] According to the method for producing a carbon-supported platinum group metal catalyst of Embodiment II of the present invention, the post-treatment includes washing, filtration, and drying.

[0211] Embodiment II of the present invention also provides a method for producing a carbon-supported platinum group metal catalyst (e.g., a platinum-carbon catalyst), comprising the following (1) to (3): (1) A carbon source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) A process for producing a sulfur-nitrogen-doped carbon material, wherein the nitrogen-source immersed carbon material obtained in step (1) is treated in thiophene containing an inert gas at 1000°C to 1500°C (preferably constant temperature treatment) for 0.5 hours to 10 hours to provide a nitrogen-doped carbon material; and, (3) A step of supporting a platinum group metal (for example, platinum) using the sulfur-nitrogen-doped carbon material obtained in step (2) as a support.

[0212] In the method for producing a carbon-supported platinum group metal catalyst, the nitrogen-source-immersed carbon material in step (1) is first dried, and then step (2) is carried out.

[0213] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst of this embodiment (e.g., platinum-carbon catalyst) is produced by a method for producing a carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst).

[0214] Embodiment II of the present invention also provides a hydrogen fuel cell that uses a carbon-supported platinum group metal catalyst according to any embodiment of Embodiment II of the present invention described above in the anode and / or cathode of the hydrogen fuel cell.

[0215] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst according to the present invention (e.g., platinum-carbon catalyst) exhibits a reduction in weight specific activity of less than 10% after 5000 cycles when used in an oxygen reduction reaction.

[0216] In one embodiment of Embodiment II, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some Embodiment II-, the ECSA is 68.93m 2 g -1 -Pt or greater, for example, 60.0m 2 g -1 -Pt~100.0m 2 g -1 -Pt

[0217] In one embodiment of Embodiment II, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, the half-wave potential is greater than 0.890 V (e.g., 0.89 V to 0.91 V) in some Embodiment II-.

[0218] In one embodiment of Embodiment II, when the carbon-supported platinum group metal catalyst (e.g., platinum-carbon catalyst) according to the present invention is used in an oxygen reduction reaction, in some Examples II-, the weight specific activity is 0.15 A mg -1 -Pt greater than (for example, 0.15Amg) -1 -Pt~0.35Amg -1 -Pt)

[0219] Compared to the relatively low weight-specific activity and insufficient stability of conventional carbon-supported platinum group metal catalysts for hydrogen fuel cells, the present invention significantly improves the weight-specific activity and stability of carbon-supported platinum group metal catalysts, particularly those with a high platinum content, by doping the surface of the carbon support with sulfur and nitrogen in specific forms.

[0220] In one embodiment of Embodiment II, the carbon-supported platinum group metal catalyst of the present invention is a platinum-carbon catalyst.

[0221] [Examples] The present invention will be described in detail below with reference to specific examples. The following examples may help those skilled in the art to further understand the present invention, but none of them are intended to limit the present invention.

[0222] Unless otherwise specified, all reagents used in this invention are chemically pure and commercially available.

[0223] [Embodiment I] Reagents, instruments, and tests This invention detects elements on the surface of a material using an X-ray photoelectron spectroscopy (XPS). The X-ray photoelectron spectroscopy used is a VG Scientifc ESCALab 220i-XL model XPS spectrometer equipped with Avantage V5.926 software. The analysis and test conditions for the X-ray photoelectron spectroscopy are as follows: the excitation source is 330W monochromatic A1K α X-rays, and the base vacuum during the analysis test is 3 × 10⁻¹⁰ -9 The value was mbar. Furthermore, the electron bonding energy was corrected using the C1s peak of the element carbon (284.3 eV), and the late peak fitting software used was XPSPEAK.

[0224] The instruments, methods, and conditions for elemental analysis included an elemental analyzer (Vario EL Cube), a reaction temperature of 1150°C, weighing of 5 mg of sample, a reduction temperature of 850°C, a carrier gas helium flow rate of 200 mL / min, an oxygen flow rate of 30 mL / min, and oxygen introduction for 70 seconds.

[0225] The instruments, methods, and conditions for determining the weight of platinum in a platinum-carbon catalyst included taking 30 mg of the prepared Pt / C catalyst, adding 30 mL of aqua regia, condensing and refluxing at 120°C for 12 hours, cooling to room temperature, taking the supernatant for dilution, and measuring the Pt content in the supernatant by ICP-AES.

[0226] The high-resolution transmission electron microscope (HRTEM) used in this invention was the JEM-2100 (HRTEM) (manufactured by JEOL Ltd.), and the test conditions for the high-resolution transmission electron microscope included an acceleration voltage of 200 kV. The particle size of nanoparticles in the sample was measured by electron microscope images.

[0227] BET Test Method: In this invention, the pore structure characteristics of the sample were measured using a Quantachrome AS-6B analyzer, the specific surface area and pore volume of the catalyst were determined by the Brunauer-Emmett-Taller (BET) method, and the pore distribution curve was determined by calculating the desorption curve using the Barrett-Joyner-Halenda (BJH) method.

[0228] The Raman detection method used in this invention was a LabRAM HR UV-NIR type confocal Raman spectrometer with a laser wavelength of 532 nm, manufactured by HORIBA Corporation of Japan.

[0229] Electrochemical performance testing: The instruments used were a Solartron analytical EnergyLab and a Princeton Applied Research (Model 636A). The method and test conditions were as follows: the catalyst polarization curve LSV was measured at 1600 rpm in O2 saturated with 0.1 M HClO4, the CV curve was measured in 0.1 M HClO4 under an Ar atmosphere, and the electrochemically active region (ECSA) was calculated. Stability was measured by scanning in O2 saturated with 0.1 M HClO4 within the range of 0.6 V to 0.95 V for 5000 cycles, followed by the measurement of the LSV and ECSA. During the measurements, the catalyst was prepared in a uniformly dispersed slurry and coated onto a 5 mm diameter glassy carbon electrode. The platinum content of the catalyst on the electrode was 3 μg to 4 μg.

[0230] Resistivity test: A 4-probe resistivity tester was used. Instrument model KDY-1, and method and test conditions: The applied pressure was 3.9 ± 0.03 MPa and the current was 500 ± 0.1 mA.

[0231] The VXC72 (Vulcan XC72, manufactured by Kabot, USA) was purchased from Suzhou Yilongcheng Energy Science and Technology Co., Ltd. Test results using the above equipment and methods showed a specific surface area of ​​258 m². 2 The pore volume is 0.388 mL / g, the oxygen content is 8.72% by weight, and I D / I G The ratio was 1.02, and the resistivity was 1.22 Ω·m.

[0232] The Ketjenblack ECP600JD (manufactured by Lion Corporation, Japan) was purchased from Suzhou Yilongcheng Energy Science and Technology Co., Ltd. Test results using the above equipment and methods showed a specific surface area of ​​1362 m². 2 The pore volume is 2.29 mL / g, the oxygen content is 6.9% by weight, and I D / I G The ratio was 1.25, and the resistivity was 1.31 Ω·m.

[0233] A commercially available platinum-carbon catalyst (Johnson Matthey's trademark HISPEC4000) was purchased from Alfa Aesar. Test results showed a platinum content of 40.2% by weight.

[0234] [Example 1] This example illustrates the preparation of a nitrogen-doped carbon support according to the present invention.

[0235] 1 g of Vulcan XC72 was immersed in 20 mL of 2.5 wt% ammonia water for 24 hours, dried in an oven at 100°C, placed in a tubular furnace, heated to 1100°C at a rate of 8°C / min, subjected to constant temperature treatment for 3 hours, and allowed to cool naturally to obtain a nitrogen-doped carbon carrier referred to as carbon carrier A.

[0236] Sample characteristics and testing XPS analysis revealed a nitrogen content of 1.43% and an oxygen content of 9.31%, with a specific surface area of ​​239 m². 2 The resistance was 1.28 Ω·m, and the coefficient was / g.

[0237] Figure 1 shows the XPS spectrum of carbon support A in Example 1.

[0238] [Example 2] This example illustrates the preparation of a nitrogen-doped carbon support according to the present invention.

[0239] 1 g of Vulcan XC72 was immersed in 15 ml of 0.7 wt% urea aqueous solution for 24 hours, dried in an oven at 100°C, placed in a tubular furnace, heated to 1200°C at a rate of 10°C / min, subjected to constant temperature treatment for 3 hours, and allowed to cool naturally to obtain a nitrogen-doped carbon support called carbon support B.

[0240] Sample characteristics and testing XPS analysis revealed a nitrogen content of 0.68% and an oxygen content of 8.92%, with a resistivity of 1.25 Ω·m.

[0241] [Example 3] This example illustrates the preparation of a nitrogen-doped carbon support according to the present invention.

[0242] 10 mL of anhydrous ethanol was added to 1 g of Ketjenblack ECP600JD, then 25 mL of 10% by weight aqueous ammonia was added and the mixture was immersed for 24 hours, dried in an oven at 100°C, then placed in a tubular furnace, heated to 1100°C at a rate of 8°C / min, subjected to constant temperature treatment for 3 hours, and allowed to cool naturally to obtain a nitrogen-doped carbon support called carbon support C.

[0243] Sample characteristics and testing XPS analysis revealed a nitrogen content of 1.48% and an oxygen content of 11.22%, with a specific surface area of ​​1369 m². 2 The resistance was 1.36 Ω·m, and the coefficient was / g.

[0244] Figure 2 shows the XPS spectrum of carbon support C in Example 3.

[0245] [Example 4] This example illustrates the preparation of a nitrogen-doped carbon support according to the present invention.

[0246] 10 mL of anhydrous ethanol was added to 1 g of Ketjenblack ECP600JD, and then 20 mL of 1 wt% urea water was added and immersed for 24 hours, dried in an oven at 100 °C, placed in a tubular furnace, and the tubular furnace was heated to 1300 °C at a rate of 10 °C / min, subjected to a constant temperature treatment for 3 hours, and naturally cooled to obtain a nitrogen-doped carbon support designated as carbon support D.

[0247] Properties and tests of the sample The nitrogen content by XPS analysis was 1.31%, the oxygen content by XPS analysis was 9.54%, and the resistivity was 1.34 Ω·m.

[0248] [Example 5] This example is provided to illustrate the preparation of the platinum-carbon catalyst according to the present invention.

[0249] Carbon support A was dispersed in deionized water at a ratio of 250 mL of water per 1 g of carbon support, 3.4 mmol of chloroplatinic acid was added per 1 g of carbon support, and ultrasonically dispersed to form a suspension. A 1 mol / L aqueous sodium carbonate solution was added to adjust the pH value of the system to 10. The suspension was heated to 80 °C, and formic acid was added with stirring for a reduction reaction. The molar ratio of formic acid to chloroplatinic acid was 50:1, and the reaction was continued for 10 hours. The mixture obtained from the reaction was filtered, washed with deionized water until the pH value of the filtrate became neutral, filtered, and dried at 100 °C to obtain a platinum-carbon catalyst.

[0250] Properties and tests of the sample The platinum content of the platinum-carbon catalyst was 39.7%.

[0251] Figure 3 shows the XPS spectrum of the platinum-carbon catalyst of Example 5.

[0252] Figure 4 shows the polarization curves of the platinum-carbon catalyst of Example 5 before and after 5000 cycles.

[0253] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0254] [Example 6] This embodiment is provided to illustrate the preparation of a platinum-carbon catalyst.

[0255] A platinum-carbon catalyst was prepared according to the method of Example 5, except that carbon carrier B produced in Example 2 was used, and 1.3 mmol of chloroplatinic acid was added per gram of carbon carrier.

[0256] Sample characteristics and testing The platinum content of the platinum-carbon catalyst was 20.1% by weight.

[0257] Figure 5 shows the XPS spectrum of the platinum-carbon catalyst of Example 6.

[0258] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0259] [Example 7] This example is provided to illustrate the preparation of a platinum-carbon catalyst according to the present invention.

[0260] Carbon support C was dispersed in deionized water at a ratio of 250 mL of water per gram of carbon support, 12 mmol of chloroplatinic acid was added per gram of carbon support, and a suspension was formed by ultrasonic dispersion. A 1 mol / L aqueous potassium hydroxide solution was added to adjust the pH of the system to 10, the suspension was heated to 80°C, and sodium borohydride was added while stirring to carry out a reduction reaction, with a molar ratio of reducing agent to platinum precursor of 5:1. The reaction was continued for 12 hours, the mixture obtained from the reaction was filtered, washed until the pH of the solution became neutral, and dried at 100°C to obtain a carbon-supported platinum catalyst.

[0261] Sample characteristics and testing The platinum content by weight of the platinum-carbon catalyst was 70.0%.

[0262] Figure 6 shows the XPS spectrum of the platinum-carbon catalyst of Example 7.

[0263] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0264] Example 8 This example is provided to explain the preparation of a platinum-carbon catalyst.

[0265] A platinum-carbon catalyst was produced according to the method of Example 7, except that carbon support D produced in Example 4 was used and 1.3 mmol of chloroplatinic acid was added per 1 g of the carbon support.

[0266] Properties and Tests of Samples The platinum content weight of the platinum-carbon catalyst was 20.1%.

[0267] Figure 7 shows the XPS spectrum of the platinum-carbon catalyst of Example 8.

[0268] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0269] Comparative Example 1 A platinum-carbon catalyst was produced according to the method of Example 5, except that the support was Vulcan XC72.

[0270] Properties and Tests of Samples The platinum content weight of the platinum-carbon catalyst was 40.1%.

[0271] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0272] Comparative Example 2 A platinum-carbon catalyst was produced according to the method of Example 7, except that the support was Ketjenblack ECP600JD and 200 mL of water and 50 mL of ethanol per 1 g of the carbon support were used for dispersion when loading Pt.

[0273] Properties and Tests of Samples The platinum content weight of the platinum-carbon catalyst was 69.7%.

[0274] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0275] [Comparative Example 3] The platinum-carbon catalyst was a commercially available catalyst purchased under the trademark HISPEC 4000.

[0276] Sample characteristics and testing The platinum content by weight of the platinum-carbon catalyst was 40.2%.

[0277] Figure 8 shows the polarization curve of the platinum-carbon catalyst of Comparative Example 3 around 5000 cycles.

[0278] The results of the platinum-carbon catalyst performance test are shown in Table 1.

[0279] [Table 1]

[0280] [Embodiment II] Reagents, instruments, and tests This invention detects elements on the surface of a material using an X-ray photoelectron spectroscopy (XPS). The X-ray photoelectron spectroscopy used is a VG Scientifc ESCALab 220i-XL X-ray spectrometer equipped with Avantage V5.926 software. The analysis and test conditions for the X-ray photoelectron spectroscopy are as follows: the excitation source is 330W monochromatic A1K α X-rays, and the base vacuum during the analysis test is 3 × 10⁻¹⁰ -9 The value was mbar. Furthermore, the electron bonding energy was corrected using the C1s peak of the element carbon (284.3 eV), and the late peak fitting software was XPSPEAK. The characteristic peaks of thiophene sulfur and nitrogen in the spectrophotograph were characteristic peaks after peak fitting.

[0281] The instruments, methods, and conditions for elemental analysis included an elemental analyzer (Vario EL Cube), a reaction temperature of 1150°C, weighing of 5 mg of sample, a reduction temperature of 850°C, a carrier gas helium flow rate of 200 mL / min, an oxygen flow rate of 30 mL / min, and oxygen introduction for 70 seconds.

[0282] The instruments, methods, and conditions for determining the weight of platinum in a platinum-carbon catalyst included taking 30 mg of the prepared Pt / C catalyst, adding 30 mL of aqua regia, condensing and refluxing at 120°C for 12 hours, cooling to room temperature, taking the supernatant for dilution, and measuring the Pt content in the supernatant by ICP-AES.

[0283] The high-resolution transmission electron microscope (HRTEM) used in this invention was the JEM-2100 (HRTEM) (manufactured by JEOL Ltd.), and the test conditions for the high-resolution transmission electron microscope included an acceleration voltage of 200 kV. The particle size of nanoparticles in the sample was measured by electron microscope images.

[0284] BET Test Method: In this invention, the pore structure characteristics of the sample were measured using a Quantachrome AS-6B analyzer, the specific surface area and pore volume of the catalyst were determined by the Brunauer-Emmett-Taller (BET) method, and the pore distribution curve was determined by calculating the desorption curve using the Barrett-Joyner-Halenda (BJH) method.

[0285] The Raman detection method used in this invention was a LabRAM HR UV-NIR type confocal Raman spectrometer with a laser wavelength of 532 nm, manufactured by HORIBA Corporation of Japan.

[0286] Electrochemical performance testing: The instruments used were a Solartron analytical EnergyLab and a Princeton Applied Research (Model 636A). The method and test conditions involved measuring the catalyst's polarization curve LSV in O2 saturated with 0.1 M HClO4 at 1600 rpm, measuring the CV curve in 0.1 M HClO4 under an Ar atmosphere, and calculating the electrochemically active region ECSA. Electrochemical performance testing: The instruments used were a Solartron analytical EnergyLab and a Princeton Applied Research (Model 636A). The method and test conditions involved measuring the catalyst's polarization curve LSV in O2 saturated with 0.1 M HClO4 at 1600 rpm, measuring the CV curve in 0.1 M HClO4 under an Ar atmosphere, and calculating the electrochemically active region ECSA. Stability was measured by scanning in O2 saturated with 0.1 M HClO4 for 5000 cycles within the range of 0.6 V to 0.95 V, followed by the measurement of the LSV and ECSA described above. During the measurement, the catalyst was prepared in a uniformly dispersed slurry and coated onto a 5 mm diameter glassy carbon electrode. The platinum content of the catalyst on the electrode was 3 μg to 4 μg.

[0287] Resistivity test: A 4-probe resistivity tester was used. Instrument model KDY-1, and method and test conditions: The applied pressure was 3.9 ± 0.03 MPa and the current was 500 ± 0.1 mA.

[0288] The VXC72 (Vulcan XC72, manufactured by Kabot, USA) was purchased from Suzhou Yilongcheng Energy Science and Technology Co., Ltd. Test results using the above equipment and methods showed a specific surface area of ​​258 m². 2 The pore volume is 0.388 mL / g, the oxygen content is 8.72% by weight, and I D / IG The ratio was 1.02, and the resistivity was 1.22 Ω·m.

[0289] The Ketjenblack ECP600JD (manufactured by Lion Corporation, Japan) was purchased from Suzhou Yilongcheng Energy Science and Technology Co., Ltd. Test results using the above equipment and methods showed a specific surface area of ​​1362 m². 2 The pore volume is 2.29 mL / g, the oxygen content is 6.9% by weight, and I D / I G The ratio was 1.25, and the resistivity was 1.31 Ω·m.

[0290] A commercially available platinum-carbon catalyst (Johnson Matthey's trademark HISPEC4000) was purchased from Alfa Aesar. Test results showed a platinum content of 40.2% by weight.

[0291] [Example II-1] This embodiment is provided to illustrate the preparation of sulfur-nitrogen-doped carbon materials.

[0292] 1 g of Vulcan XC72 was immersed in 20 mL of 2 wt% ammonia water for 24 hours, dried in an oven at 100°C, then placed in a tubular furnace. Carrier gas (nitrogen) that had passed through a bubbling bottle filled with thiophene was supplied to the tubular furnace, heated to 1200°C at a rate of 10°C / min, subjected to constant temperature treatment for 3 hours, and allowed to cool naturally to obtain a sulfur-nitrogen-doped carbon material called carrier A. The weight ratio of Vulcan XC72 to thiophene was 3:1, and the amount of thiophene was calculated as the amount of sulfur contained in the thiophene. The amount of thiophene was controlled by the carrier gas supply rate, and the carrier gas supply rate corresponding to different amounts of thiophene was pre-adjusted according to the supply time.

[0293] Sample characteristics and testing I. Sulfur-nitrogen-doped carbon materials The sulfur content by weight determined by XPS analysis was 1.25%. The nitrogen content by weight determined by XPS analysis was 0.54%. The specific surface area is 211 m². 2 The pore volume is 0.421 mL / g, The resistivity was 1.31 Ω·m.

[0294] Figure II-1 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-1.

[0295] Figure II-2 shows the XPS spectrum of nitrogen in the sulfur-nitrogen-doped carbon material of Example II-1.

[0296] [Example II-2] 1 g of Vulcan XC72 was immersed in 20 mL of 20 wt% ammonia water for 24 hours, dried in an oven at 100°C, then placed in a tubular furnace. Carrier gas (nitrogen) that had passed through a bubbling bottle filled with thiophene was supplied to the tubular furnace, and the furnace was heated to 1300°C at a rate of 10°C / min for 3 hours. After natural cooling, a sulfur-nitrogen-doped carbon material called carrier B was obtained. The weight ratio of Vulcan XC72 to thiophene was 9:1, and the amount of thiophene was calculated as the amount of sulfur contained in the thiophene. The amount of thiophene was controlled by the carrier gas supply rate, and the carrier gas supply rate corresponding to different amounts of thiophene was pre-adjusted according to the supply time.

[0297] Sample characteristics and testing XPS analysis revealed a sulfur content of 0.91% and a nitrogen content of 0.62%, with a resistivity of 1.29 Ω·m.

[0298] Figure II-3 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-2.

[0299] [Example II-3] 10 mL of anhydrous ethanol was added to 1 g of Ketjenblack ECP600JD, and 20 mL of 20 wt% aqueous ammonia was added and the mixture was immersed for 24 hours. It was then dried in an oven at 100°C, and subsequently placed in a tubular furnace. Carrier gas (nitrogen) that had passed through a bubbling bottle filled with thiophene was supplied to the tubular furnace, and the mixture was heated to 1200°C at a rate of 10°C / min. This was subjected to constant temperature treatment for 3 hours, followed by natural cooling to obtain a sulfur-nitrogen-doped carbon material referred to as carrier C. The weight ratio of Ketjenblack ECP600JD to thiophene was 8:1, and the amount of thiophene was calculated as the amount of sulfur contained in the thiophene. The amount of thiophene was controlled by the carrier gas supply rate, and the carrier gas supply rate corresponding to different amounts of thiophene was pre-adjusted according to the supply time.

[0300] Sample characteristics and testing I. Sulfur-nitrogen-doped carbon materials XPS analysis revealed a sulfur content of 0.72% and a nitrogen content of 1.84%, with a specific surface area of ​​1317 m². 2 The resistance was 1.38 Ω·m, and the coefficient was / g.

[0301] Figure II-4 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-3.

[0302] [Example II-4] This embodiment is provided to illustrate the preparation of sulfur-nitrogen-doped carbon materials.

[0303] 1 g of Vulcan XC72 was immersed in 20 mL of 2 wt% ammonia water for 24 hours, dried in an oven at 100°C, then placed in a tubular furnace and heated to 1200°C at a rate of 10°C / min under the protection of nitrogen gas, and subjected to constant temperature treatment for 3 hours. Then, carrier gas (nitrogen) that had passed through a bubbling bottle filled with thiophene was supplied to the tubular furnace, and constant temperature treatment at 1200°C was continued for 3 hours, followed by natural cooling to obtain a sulfur-nitrogen-doped carbon material called carrier D. The weight ratio of Vulcan XC72 to thiophene was 3:1, and the amount of thiophene was calculated as the amount of sulfur contained in the thiophene. The amount of thiophene was controlled by the carrier gas supply rate, and the carrier gas supply rate corresponding to different amounts of thiophene was pre-adjusted according to the supply time.

[0304] Sample characteristics and testing I. Sulfur-nitrogen-doped carbon materials XPS analysis revealed a sulfur content of 1.14% and a nitrogen content of 0.14%.

[0305] Figure II-5 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-4.

[0306] [Example II-5] This example is provided to illustrate the preparation of a platinum-carbon catalyst according to the present invention.

[0307] Carbon carrier A was dispersed in deionized water at a ratio of 250 mL of water per gram of carbon carrier, 3.4 mmol of chloroplatinic acid per gram of carbon carrier was added, and a suspension was formed by ultrasonic dispersion. A 1 mol / L aqueous sodium carbonate solution was added to adjust the pH of the system to 10, the suspension was heated to 80°C, and formic acid was added while stirring to carry out a reduction reaction, with a molar ratio of formic acid to chloroplatinic acid of 50:1. The reaction was continued for 10 hours, the mixture obtained from the reaction was filtered, washed with deionized water until the pH of the filtrate became neutral, filtered, and dried at 100°C to obtain a platinum-carbon catalyst.

[0308] Sample characteristics and testing The platinum content of the platinum-carbon catalyst was 39.9% by weight.

[0309] Figure II-6 shows the TEM pattern of the platinum-carbon catalyst of Example II-5.

[0310] Figure II-7 shows the polarization curve of the platinum-carbon catalyst of Example II-5.

[0311] Figure II-8 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-5.

[0312] Figure II-9 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-5.

[0313] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0314] [Example II-6] This example is provided to illustrate the preparation of a platinum-carbon catalyst according to the present invention.

[0315] A platinum-carbon catalyst was prepared according to the method of Example II-5, except that carbon support B prepared in Example II-2 was used, and 1.3 mmol of chloroplatinic acid was added per gram of carbon support.

[0316] Sample characteristics and testing The platinum content of the platinum-carbon catalyst was 20.3% by weight.

[0317] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0318] [Example II-7] This example is provided to illustrate the preparation of a platinum-carbon catalyst according to the present invention.

[0319] Carbon support C was dispersed in deionized water at a ratio of 250 mL of water per gram of carbon support, 12 mmol of chloroplatinic acid was added per gram of carbon support, and a suspension was formed by ultrasonic dispersion. A 1 mol / L aqueous potassium hydroxide solution was added to adjust the pH of the system to 10, the suspension was heated to 80°C, and sodium borohydride was added while stirring to carry out a reduction reaction, with a molar ratio of reducing agent to platinum precursor of 5:1. The reaction was continued for 12 hours, the mixture obtained from the reaction was filtered, washed until the pH of the solution became neutral, and dried at 100°C to obtain a carbon-supported platinum catalyst.

[0320] Sample characteristics and testing The platinum content of the platinum-carbon catalyst was 69.8% by weight.

[0321] Figure II-10 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-7.

[0322] Figure II-11 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-7.

[0323] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0324] [Example II-8] This example is provided to illustrate the preparation of a platinum-carbon catalyst according to the present invention.

[0325] The platinum-carbon catalyst was prepared according to the method of Example II-5, except that the carbon support D prepared in Example II-4 was used.

[0326] Sample characteristics and testing The platinum content of the platinum-carbon catalyst was 39.9% by weight.

[0327] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0328] [Comparative Example II-1] Sulfur-nitrogen-doped carbon material was prepared in the same manner as in Example II-1, except that the tubular furnace was heated to 1200°C at a rate of 3°C / min.

[0329] A platinum-carbon catalyst was prepared in the same manner as in Example II-5, except that the carbon support was the sulfur-nitrogen-doped carbon material prepared in Comparative Example II-1.

[0330] Sample characteristics and testing I. Sulfur-nitrogen-doped carbon materials XPS analysis revealed a sulfur content of 1.29% by weight, a nitrogen content of 0.58% by weight, and a resistivity of 1.32 Ω·m.

[0331] Figure II-12 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-1.

[0332] II. Platinum-Carbon Catalysts The platinum content by weight of the platinum-carbon catalyst was 40.1%.

[0333] Figure II-13 shows the TEM pattern of the platinum-carbon catalyst of Comparative Example II-1.

[0334] Figure II-14 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-1.

[0335] [Comparative Example II-2] The sulfur-nitrogen-doped carbon material was prepared in the same manner as in Example II-1, except that a constant temperature treatment was performed at 700°C during the manufacturing of the sulfur-nitrogen-doped carbon material.

[0336] Sample characteristics and testing For the sulfur-nitrogen-doped carbon material of Comparative Example II-2, the sulfur content by weight, as determined by XPS analysis, was 0.967%, and the nitrogen content by weight, as determined by XPS analysis, was 0.92%.

[0337] Figure II-15 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-2.

[0338] [Comparative Example II-3] The platinum-carbon catalyst was a commercially available catalyst purchased under the trademark HISPEC 4000.

[0339] Sample characteristics and testing The platinum content by weight of the platinum-carbon catalyst was 40.2%.

[0340] Figure II-16 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-3.

[0341] [Comparative Example II-4] 10 mL of anhydrous ethanol was added to 1 g of Ketjenblack ECP600JD, then 25 mL of 10% by weight aqueous ammonia was added and the mixture was immersed for 24 hours. The mixture was then dried in an oven at 100°C, placed in a tubular furnace, heated to 1100°C at a rate of 8°C / min, and supported at a constant temperature for 3 hours. After natural cooling, a nitrogen-doped carbon support was obtained.

[0342] The nitrogen-doped carbon carrier described above was dispersed in deionized water at a ratio of 250 mL of water per gram of carbon carrier. 12 mmol of chloroplatinic acid was added per gram of carbon carrier, and the suspension was dispersed ultrasonically. A 1 mol / L aqueous potassium hydroxide solution was added to adjust the pH of the system to 10. The suspension was heated to 80°C, and sodium borohydride was added while stirring to carry out a reduction reaction. The molar ratio of the reducing agent to the platinum precursor was 5:1, and the reaction was continued for 12 hours. The mixture obtained from the reaction was filtered, washed until the pH of the solution became neutral, and dried at 100°C to obtain a carbon-supported platinum catalyst.

[0343] Sample characteristics and testing XPS analysis of the nitrogen-doped carbon carrier revealed a nitrogen content of 1.48% by weight.

[0344] The platinum content by weight of the platinum-carbon catalyst was 70.0%.

[0345] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0346] [Comparative Example II-5] Ketjenblack ECP600JD was placed in a tubular furnace, and carrier gas (nitrogen) that had passed through a bubbling bottle filled with thiophene was supplied to the tubular furnace. The furnace was heated to 1200°C at a rate of 10°C / min and processed at a constant temperature for 3 hours, followed by natural cooling to obtain a sulfur-doped carbon support. The weight ratio of Ketjenblack ECP600JD to thiophene was 20:1, and the amount of thiophene was calculated as the amount of sulfur contained in the thiophene. The amount of thiophene was controlled by the carrier gas supply rate, and the carrier gas supply rate corresponding to different amounts of thiophene was pre-adjusted according to the supply time.

[0347] The sulfur-doped carbon carrier described above was dispersed in deionized water at a ratio of 250 mL of water per gram of carbon carrier, 12 mmol of chloroplatinic acid was added per gram of carbon carrier, and a suspension was formed by ultrasonic dispersion. A 1 mol / L aqueous potassium hydroxide solution was added to adjust the pH of the system to 10, the suspension was heated to 80°C, and sodium borohydride was added while stirring to carry out a reduction reaction, with a molar ratio of reducing agent to platinum precursor of 5:1. The reaction was continued for 12 hours, the mixture obtained from the reaction was filtered, washed until the pH of the solution became neutral, and dried at 100°C to obtain a carbon-supported platinum catalyst.

[0348] Sample characteristics and testing XPS analysis of the sulfur-doped carbon carrier revealed a sulfur content of 0.76% by weight.

[0349] The platinum content by weight of the platinum-carbon catalyst was 70.2%.

[0350] The results of the platinum-carbon catalyst performance test are shown in Table II-1.

[0351] [Table 2]

[0352] As shown in Figures II-12 and II-15, the sulfur-doped carbon material not according to the present invention contained not only a characteristic peak between 163ev and 166ev (which was estimated by analysis to be a characteristic peak of thiopheneic sulfur), but also sulfur in an oxidized state.

[0353] As shown in Table II-1, when comparing the example with Comparative Example II-3, sulfur-nitrogen-doped conductive carbon black significantly improved the ECSA, weight-specific activity, and stability of the platinum-carbon catalyst.

[0354] As shown in Table II-1, a comparison of Example II-7 with Comparative Examples II-4 and II-5 revealed that conductive carbon black having a characteristic peak between 163ev and 166ev or a single pyrrole nitrogen simultaneously improved the overall performance of the platinum-carbon catalyst, such as its weight-specific activity and stability, compared to conductive carbon black having a characteristic peak between 163ev and 166ev or a single pyrrole nitrogen. [Brief explanation of the drawing]

[0355] [Figure I-1] Figure I-1 shows the XPS spectrum of the nitrogen-doped carbon support of Example 1. [Figure I-2] Figure I-2 shows the XPS spectrum of the nitrogen-doped carbon support of Example 3. [Figure I-3] Figure I-3 shows the XPS spectrum of the platinum-carbon catalyst of Example 5. [Figure I-4] Figure I-4 shows the polarization curve of the platinum-carbon catalyst of Example 5 around 5000 cycles. [Figure I-5] Figure I-5 shows the XPS spectrum of the platinum-carbon catalyst of Example 6. [Figure I-6] Figure I-6 shows the XPS spectrum of the platinum-carbon catalyst of Example 7. [Figure I-7] Figure I-7 shows the XPS spectrum of the platinum-carbon catalyst of Example 8. [Figure I-8]Figure I-8 shows the polarization curve of the platinum-carbon catalyst of Comparative Example 3 around 5000 cycles. [Figure II-1] Figure II-1 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-1. [Figure II-2] Figure II-2 shows the XPS spectrum of nitrogen in the sulfur-nitrogen-doped carbon material of Example II-1. [Figure II-3] Figure II-3 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-2. [Figure II-4] Figure II-4 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-3. [Figure II-5] Figure II-5 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Example II-4. [Figure II-6] Figure II-6 shows the TEM pattern of the platinum-carbon catalyst of Example II-5. [Figure II-7] Figure II-7 shows the polarization curve of the platinum-carbon catalyst of Example II-5. [Figure II-8] Figure II-8 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-5. [Figure II-9] Figure II-9 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-5. [Figure II-10] Figure II-10 shows the XPS spectrum of sulfur in the platinum-carbon catalyst of Example II-7. [Figure II-11] Figure II-11 shows the XPS spectrum of nitrogen in the platinum-carbon catalyst of Example II-7. [Figure II-12] Figure II-12 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-1. [Figure II-13] Figure II-13 shows the TEM pattern of the platinum-carbon catalyst of Comparative Example II-1. [Figure II-14] Figure II-14 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-1. [Figure II-15]Figure II-15 shows the XPS spectrum of sulfur in the sulfur-nitrogen-doped carbon material of Comparative Example II-2. [Figure II-16] Figure II-16 shows the polarization curve of the platinum-carbon catalyst of Comparative Example II-3.

Claims

1. XPS analysis of carbon-supported platinum group metal catalysts １ｓ Regarding the spectral peaks, there is a characteristic peak of pyrroleous nitrogen between 399 ev and 400.5 ev, and there are no other characteristic peaks, or substantially none, between 395 ev and 405 ev. Here, the electron bonding energy is corrected by the 284.3 eV C1s peak of the element carbon, and "substantially no other characteristic peaks between 395 eV and 405 eV" means that the peak area of ​​other characteristic peaks accounts for less than 10%. The support for the carbon-supported platinum group metal catalyst is nitrogen-doped conductive carbon black. The carbon-supported platinum group metal catalyst is characterized by containing platinum in an amount of 20% to 70% by weight, and is a carbon-supported platinum group metal catalyst for proton membrane hydrogen fuel cells.

2. The carbon-supported platinum group metal catalyst according to claim 1, characterized in that the support of the carbon-supported platinum group metal catalyst is sulfur-nitrogen-doped conductive carbon black.

3. S in XPS analysis ２Ｐ The carbon-supported platinum group metal catalyst according to claim 1, characterized in that, regarding the spectral peaks, between 160 ev and 170 ev, the peak area of ​​the peak between 163 ev and 166 ev accounts for more than 92%.

4. The carbon-supported platinum group metal catalyst according to claim 1, characterized in that the conductive carbon black is selected from one or more of the superconducting carbon black of the Ketjen black series, the conductive carbon black of the Cabot series, and the conductive carbon black of the Evonik-Degussa series.

5. The carbon-supported platinum group metal catalyst according to claim 1, characterized in that the catalyst further comprises a platinum group metal selected from palladium (Pd), rhodium (Rh), iridium (Ir), osmium (Os), and ruthenium (Ru).

6. The carbon-supported platinum group metal catalyst has a resistivity of less than 10 Ω·m. The carbon-supported platinum group metal catalyst according to claim 1, characterized in that the resistivity is measured using a four-probe resistivity tester of instrument model KDY-1, with an applied pressure of 3.9 ± 0.03 MPa and a current of 500 ± 0.1 mA.

7. A hydrogen fuel cell characterized in that a carbon-supported platinum group metal catalyst for proton membrane hydrogen fuel cells described in any one of claims 1 to 6 is used as the anode and / or cathode of the hydrogen fuel cell.

8. It is nitrogen-doped conductive carbon black, N in XPS analysis １ｓ This carbon material for proton membrane hydrogen fuel cells is characterized by having a characteristic peak of pyrroleous nitrogen between 399 eV and 400.5 eV in its spectrum, but lacking any other characteristic peaks between 395 eV and 405 eV, where the electron bonding energy is corrected by the 284.3 eV C1s peak of elemental carbon.

9. A method for producing a carbon-supported platinum group metal catalyst according to any one of claims 1 to 6, comprising the following steps (1) to (3): (1) A nitrogen source immersion step, in which a carbon material is mixed with an aqueous solution of a nitrogen source and immersed to obtain a nitrogen source immersed carbon material; (2) A process for producing the nitrogen-doped carbon material, wherein the nitrogen-source immersed carbon material obtained in step (1) is heated in an inert gas at a heating rate of 8°C / min to 15°C / min to 1000°C to 1500°C, and then subjected to constant temperature treatment for 0.5 hours to 10 hours; and (3) A platinum group metal support step, wherein the platinum group metal is supported on the nitrogen-doped carbon material obtained in step (2) above, The carbon material is conductive carbon black, in this process.

10. The method according to claim 9, characterized in that in step (2), the constant temperature treatment is performed at a temperature of 1150°C to 1450°C.

11. The method according to claim 9, characterized in that the nitrogen source is aqueous ammonia or urea.

12. The method according to claim 9, characterized in that the weight ratio of the carbon material to the nitrogen source is 30:1 to 1:2, calculated as the elemental nitrogen contained.

13. The method according to claim 9, characterized in that the carbon material has an oxygen content of more than 4% by weight as determined by XPS analysis.

14. The method according to claim 9, characterized in that the step of supporting the platinum group metal includes the following (a) to (c): (a) Disperse the nitrogen-doped carbon material and platinum group metal precursor obtained in step (2) in an aqueous phase and adjust the pH value to 8 to 12; (b) Adding a reducing agent for reduction; and (c) Separate the solid and subject it to post-treatment to obtain a platinum-carbon catalyst.

15. The platinum group metal precursor is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate. The method according to claim 14, characterized in that the concentration of the platinum group metal precursor is 0.5 mol / L to 5 mol / L.

16. In step (b) above, the reducing agent is selected from the group consisting of citric acid, ascorbic acid, formaldehyde, formic acid, ethylene glycol, sodium citrate, hydrazine hydrate, sodium borohydride, and glycerol. The molar ratio of the reducing agent to the platinum is 2 to 100. The method according to claim 14, characterized in that the reduction is carried out at a temperature of 50°C to 150°C for 2 to 15 hours.

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