CN114426268A

CN114426268A - Sulfur-phosphorus doped carbon material, platinum-carbon catalyst, and preparation methods and applications thereof

Info

Publication number: CN114426268A
Application number: CN202011012749.XA
Authority: CN
Inventors: 赵红; 王厚朋; 荣峻峰; 谢南宏; 张家康; 彭茜; 顾贤睿
Original assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Current assignee: Sinopec Research Institute of Petroleum Processing; China Petroleum and Chemical Corp
Priority date: 2020-09-24
Filing date: 2020-09-24
Publication date: 2022-05-03
Anticipated expiration: 2040-09-24
Also published as: CN114426268B

Abstract

The invention relates to a sulfur-phosphorus doped carbon material, a platinum-carbon catalyst, a preparation method and application thereof, wherein in XPS analysis of the sulfur-phosphorus doped carbon material, only one sulfur characteristic peak exists between 160ev and 170 ev; there is only one characteristic peak of phosphorus between 125eV and 145 eV. The platinum-carbon catalyst prepared from the sulfur-phosphorus doped carbon material has high quality specific activity, ECSA and stability.

Description

Sulfur-phosphorus doped carbon material, platinum-carbon catalyst, and preparation methods and applications thereof

Technical Field

The invention relates to a sulfur-phosphorus doped carbon material, a platinum-carbon catalyst, and a preparation method and application thereof.

Background

Carbon materials are widely available and abundant in nature, and have been widely used in various technical fields. In the field of chemistry, carbon materials are both important supports and commonly used catalysts. The carbon element has rich bonding modes, and the carbon material can be modified in various modes to obtain better performance.

The Oxygen Reduction Reaction (ORR) is a key reaction in the electrochemical field, for example in fuel cells and metal air cells, and is a major factor affecting cell performance. The carbon material doped with atoms can be directly used as a catalyst for oxygen reduction reaction. When used as an oxygen reduction catalyst, it has been reported in the literature that a carbon material is doped with elements such as nitrogen, phosphorus, boron, sulfur, fluorine, chlorine, bromine, iodine, etc., wherein nitrogen has a radius close to that of carbon atoms and easily enters into a carbon lattice, and thus is the most commonly used doping element. Phosphorus and nitrogen belong to the same main group, but in the case of a doped carbon material, phosphorus has characteristics that are substantially different from those of nitrogen due to differences in atomic radius and electronegativity. At present, in the literature reports about phosphorus-doped carbon materials, the catalytic performance of the materials is generally low, and the catalytic mechanism is not uniformly and definitely known. Although there are many reports of doped carbon materials as fuel cell catalysts and some research results show better activity, there is a large gap compared to platinum carbon catalysts and is far from commercial application. On one hand, the combination mode of the heteroatom and the carbon material and the catalytic mechanism thereof are not fully known in the field; on the other hand, each heteroatom has multiple bonding modes with the carbon material, and the situation is more complicated when multiple heteroatoms are doped, so that how to control the bonding mode of the heteroatoms and the carbon material is the difficulty of doping atoms. In addition, such catalysts are generally not suitable for acidic environments, especially for important Proton Exchange Membrane Fuel Cells (PEMFCs).

The most effective oxygen reduction catalyst to date is the platinum carbon catalyst, and the currently used commercial platinum carbon catalyst has an undesirable dispersion of platinum metal and is subject to agglomeration deactivation, and on the other hand, platinum dissolution and agglomeration at the cathode of a hydrogen fuel cell causes a significant decrease in platinum surface area over time, affecting fuel cell life. It is highly desirable in the art to substantially increase its catalytic activity and stability in an attempt to facilitate its large-scale commercial use. Factors influencing the activity and stability of the platinum-carbon catalyst are many and complex, and some literatures believe that the activity and stability of the platinum-carbon catalyst are related to the particle size, morphology and structure of platinum, and the type, property and platinum loading of a carrier. In the prior art, the performance of the platinum-carbon catalyst is improved mainly by controlling the particle size, morphology and structure of platinum, the specific surface area and pore structure of a carrier; there is also a literature report that modifying groups are attached to the carbon surface to improve the performance of platinum-carbon catalysts by modifying the carbon support.

The platinum loading of the platinum-carbon catalyst of the hydrogen fuel cell in practical application is at least more than 20 wt%, which is much more difficult than the manufacturing difficulty of the chemical platinum-carbon catalyst (the platinum loading is less than 5 wt%). The platinum-carrying quantity is improved, so that a thinner membrane electrode with better performance can be manufactured, but the platinum-carrying quantity is greatly improved, so that the accumulation among platinum metal particles is easily caused, and the utilization rate of an active site is sharply reduced. How to more effectively utilize the catalytic active sites of the platinum metal particles and increase the contactable three-phase catalytic reaction interface, thereby improving the platinum utilization rate and the comprehensive performance of the fuel cell and the metal-air battery, is a key problem to be solved in the field.

The carbon carrier has more defect sites which are beneficial to improving the platinum carrying amount, but simultaneously aggravates carbon corrosion and reduces the stability of the catalyst. The carbon corrosion can be effectively relieved by improving the graphitization degree, but the surface of the carbon carrier is chemically inert due to high graphitization degree, so that platinum is difficult to be uniformly dispersed on the carbon carrier, and the problem is particularly difficult when the platinum carrying amount is high.

The chemical reduction method is a commonly used method for preparing the platinum-carbon catalyst, and has the advantages of simple process and low utilization rate and catalytic activity of platinum. The reason for this may be that the platinum nanoparticles are not uniformly dispersed due to irregularities in the pore structure of the carbon support.

The information disclosed in the foregoing background section is only for enhancement of background understanding of the invention and may include information that is not already known to those of ordinary skill in the art.

Disclosure of Invention

It is a first object of the present invention to provide a doped carbon material in which the doping element is more uniformly combined with carbon. It is a second object of the present invention to provide a platinum carbon catalyst having an improved combination of properties. It is a third object of the present invention to provide a platinum-carbon catalyst with a higher platinum loading in addition to the aforementioned objects. A fourth object of the present invention is to improve the aqueous phase reduction process for making platinum carbon catalysts.

In order to achieve the above object, the present invention provides the following technical solutions.

1. A sulfur-phosphorus doped carbon material characterized by S analyzed by XPS_2PAmong the peaks, only the peak characteristic to the thiophene type sulfur was observed between 160 to 170 eV.

2. The sulfur-phosphorus doped carbon material according to 1, wherein P is analyzed by XPS_2pAmong the spectral peaks, there is a characteristic peak between 125eV and 145 eV.

3. The sulfur-phosphorus doped carbon material according to 2, wherein the characteristic peaks of the thiophene-type sulfur are bimodal and are respectively 163.5 +/-0.5 ev and 164.7 +/-0.5 ev.

4. The sulfur-phosphorus doped carbon material according to any one of the above, characterized in that its resistivity is <10 Ω · m, preferably <5 Ω · m, more preferably <3 Ω · m.

5. The sulfur-phosphorus doped carbon material is characterized in that in XPS analysis, the sulfur mass fraction is 0.1-5%, and the phosphorus mass fraction is 0.01-5%; preferably, the mass fraction of sulfur is 0.2-3%, and the mass fraction of phosphorus is 0.02-3%; more preferably, the sulfur mass fraction is 0.3% to 2%. More preferably, the phosphorus content is 0.05-2 wt%.

6. A sulfur-phosphorus doped carbon material according to any one of the preceding claims, characterized in that it has a specific surface area of 10m²/g～2000m²A/g, preferably of 200m²/g～2000m²(ii)/g; the pore volume is 0.02mL/g to 6.0mL/g, preferably 0.2mL/g to 3.0 mL/g.

7. The sulfur-phosphorus doped carbon material is characterized in that the sulfur-phosphorus doped carbon material is sulfur-phosphorus doped graphene, sulfur-phosphorus doped carbon nano tubes or sulfur-phosphorus doped conductive carbon black.

8. A sulfur-phosphorus doped carbon material according to any one of the preceding claims, characterized in that said conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXAXK 40B 2.

9. A preparation method of a sulfur-phosphorus doped carbon material comprises the following steps:

(1) and (3) doping phosphorus: contacting a carbon material with a phosphorus source, and treating for 0.5-10 h at 300-800 ℃ in an inert gas to obtain a phosphorus-doped carbon material; and

(2) a step of doping sulfur: and (2) contacting the phosphorus-doped carbon material in the step (1) with a sulfur source, and treating for 0.5-10 h at 400-1500 ℃ in inert gas to obtain the phosphorus-doped carbon material.

10. The preparation method of the sulfur-phosphorus doped carbon material is characterized in that the phosphorus source is one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogen phosphate, dihydrogen phosphate, phosphite and hypophosphite.

11. The preparation method of the sulfur-phosphorus doped carbon material is characterized in that the mass ratio of the carbon material to the phosphorus source is 10000: 1-20: 1; preferably 2500: 1-30: 1.

12. the preparation method of the sulfur-phosphorus doped carbon material is characterized in that the sulfur source is elemental sulfur.

13. The preparation method of the sulfur-phosphorus doped carbon material is characterized in that the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1; preferably 10: 1-4: 1, more preferably 8: 1-4: 1.

14. the method for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, characterized in that the temperature in (1) is 400 ℃ to 600 ℃.

15. The method for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein the temperature in (2) is 1000 ℃ to 1500 ℃, preferably 1100 ℃ to 1300 ℃.

16. The process for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein the treatment time in (1) and/or (2) is 1 to 5 hours, preferably 2 to 4 hours.

17. The preparation method of the sulfur-phosphorus doped carbon material is characterized in that the carbon material is graphene, carbon nano tubes or conductive carbon black.

18. A process for the preparation of a carbon material doped with sulfur and phosphorus according to any one of the preceding claims, characterized in that the conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXAXK 40B 2.

19. The method for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein the carbon material in (1) has an oxygen mass fraction of more than 4%, preferably 4% to 15%, in XPS analysis.

20. The method for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein the carbon material in (1) has a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <2 Ω · m.

21. A process for producing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein the carbon material in (1) has a specific surface area of 10m²/g～2000m²A/g, preferably of 200m²/g～2000m²(ii)/g; the pore volume is 0.02mL/g to 6mL/g, preferably 0.2mL/g to 3 mL/g.

22. The method for preparing the sulfur-phosphorus doped carbon material is characterized in that in the step (1), the carbon material is contacted with a phosphorus source in a mode that: the carbon material is impregnated in an aqueous solution of a phosphorus source and then dried.

23. The method for preparing a sulfur-phosphorus doped carbon material according to any one of the preceding claims, wherein in (2), the phosphorus doped carbon material is contacted with a sulfur source in a manner that: the phosphorus doped carbon material is mixed with elemental sulphur.

24. A sulfur-phosphorus doped carbon material, which is characterized by being prepared by any one of the methods.

25. The sulfur-phosphorus doped carbon material is applied to electrochemistry as an electrode material.

26. The platinum-carbon catalyst is characterized by comprising a carbon carrier and platinum metal loaded on the carbon carrier, wherein the carbon carrier is a sulfur-phosphorus doped carbon material; XPS analyzed S of the platinum carbon catalyst_2PAmong the peaks, only the peak characteristic to the thiophene type sulfur was observed between 160 to 170 eV.

27. A platinum-carbon catalyst according to any one of the preceding claims, characterised in that P is analysed in its XPS_2pAmong the spectral peaks, there was no characteristic peak between 125 to 145 eV.

28. The platinum-carbon catalyst according to any of the preceding claims, characterized in that the platinum-carbon catalyst has a resistivity of <10 Ω · m, preferably <2 Ω · m.

29. The platinum-carbon catalyst is characterized in that the sulfur-phosphorus doped carbon material is sulfur-phosphorus doped graphene, sulfur-phosphorus doped carbon nano tubes or sulfur-phosphorus doped conductive carbon black.

30. A platinum-carbon catalyst according to any one of the preceding claims, characterised in that the conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXAXK 40B 2.

31. A method of preparing a platinum carbon catalyst comprising:

(1) a step of producing a phosphorus-doped carbon material: contacting a carbon material with a phosphorus source, and treating for 0.5-10 h at 300-800 ℃ in an inert gas to obtain a phosphorus-doped carbon material;

(2) a step of producing a sulfur-phosphorus doped carbon material: contacting the phosphorus-doped carbon material in the step (1) with a sulfur source, and treating for 0.5-10 h at 400-1500 ℃ in inert gas to obtain the phosphorus-doped carbon material;

(3) and (3) taking the sulfur and phosphorus doped carbon material obtained in the step (2) as a carrier to load platinum.

32. The preparation method of any one of the platinum-carbon catalysts is characterized in that in the step (1), the phosphorus source is one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogen phosphate, dihydrogen phosphate, phosphite and hypophosphite.

33. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, wherein in (1), the mass ratio of the carbon material to the phosphorus source is 10000: 1-20: 1; preferably 2500: 1-30: 1.

34. the method for preparing a platinum-carbon catalyst according to any one of the preceding claims, characterized in that in (2), the sulfur source is elemental sulfur.

35. The method for producing a platinum-carbon catalyst according to any one of the preceding claims, wherein in (2), the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1; preferably 10: 1-4: 1, more preferably 8: 1-4: 1.

36. the method for producing a platinum-carbon catalyst according to any of the above processes, wherein the temperature in the step (1) is 400 to 600 ℃.

37. The process for producing a platinum-carbon catalyst according to any of the above processes, wherein the temperature in the step (2) is 1000 to 1500 ℃, preferably 1100 to 1300 ℃.

38. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, wherein the treatment time in (1) and/or (2) is 1 to 5 hours, preferably 2 to 4 hours.

39. The preparation method of any one of the platinum-carbon catalysts is characterized in that the carbon material is graphene, conductive carbon black or carbon nanotubes.

40. The preparation method of any one of the platinum-carbon catalysts is characterized in that the conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXAXK 40B 2.

41. The method for producing a platinum-carbon catalyst according to any one of the preceding claims, wherein in (1), the carbon material has an oxygen mass fraction of more than 4%, preferably 4% to 15%, in XPS analysis.

42. The method for producing a platinum-carbon catalyst according to any one of the above processes, wherein (1) the carbon material has a resistivity of <10. omega. m, preferably <5. omega. m, more preferably <2. omega. m.

43. The method for producing a platinum-carbon catalyst according to any one of the preceding claims, wherein (1) the carbon material has a specific surface areaIs 10m²/g～2000m²A/g, preferably of 200m²/g～2000m²(ii)/g; the pore volume is 0.02mL/g to 6mL/g, preferably 0.2mL/g to 3 mL/g.

44. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, wherein the step of supporting platinum comprises:

(a) dispersing the sulfur-phosphorus doped carbon material obtained in the step (2) and a platinum precursor in a water phase, and adjusting the pH value to 8-12 (preferably, adjusting the pH value to 10 +/-0.5);

(b) adding a reducing agent for reduction;

(c) separating out solid, and post-treating to obtain the platinum-carbon catalyst.

45. The preparation method of any one of the platinum-carbon catalysts is characterized in that in (a), the platinum precursor is chloroplatinic acid, potassium chloroplatinate or sodium chloroplatinate; the concentration of the platinum precursor is 0.5-5 mol/L.

46. The preparation method of any one of the platinum-carbon catalysts is characterized in that in the step (b), the reducing agent is one or more 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 2-100; the reduction temperature is 60-90 ℃; the reduction time is 4-15 h.

47. A platinum-carbon catalyst is characterized by being prepared by any one of the preparation methods of the platinum-carbon catalyst.

48. A hydrogen fuel cell, characterized in that any of the foregoing platinum-carbon catalysts is used in the anode and/or cathode of the hydrogen fuel cell.

The heteroatom and the carbon material have various combination modes, and the combination mode of the heteroatom and the carbon material is influenced by different doping methods and raw materials and different operation steps and conditions in the doping process, so that the property difference of the heteroatom and the carbon material is caused, and the functions of the heteroatom and the carbon material are changed. The situation is more complicated when multiple heteroatoms are doped simultaneously. In the art, how to control the bonding mode of the heteroatom to the carbon material is a difficulty in doping atoms. Control of the manner in which heteroatoms are bonded to carbon materials makes it possible to produce materials with unique propertiesCarbon material, thereby making it suitable for a particular use. In the production of a platinum catalyst using a carbon material as a carrier, not only functions of dispersing and fixing platinum particles of the carbon material but also functions of electron transfer, diffusion of reactant molecules, and the like of the carbon material are considered. The invention discovers that a carbon material with unique properties can be obtained in a wide sulfur doping temperature range by doping the carbon material with phosphorus and then doping the carbon material with sulfur, and S of the sulfur can be obtained in XPS analysis of the carbon material_2pIn the spectrum, there is only one characteristic peak of sulfur between 160eV and 170 eV. Further research also finds that the sulfur-phosphorus doped carbon material can improve the comprehensive performance of the platinum-carbon catalyst of the hydrogen fuel cell.

Compared with the prior art, the invention can realize the following beneficial technical effects.

First, the manufacturing method of the present invention is simple, and a carbon material having a uniform sulfur-carbon binding mode can be obtained in a wide temperature range, and in XPS analysis of the carbon material, S of sulfur is present_2pIn the spectrogram, only the characteristic peak of the thiophenic sulfur exists.

Secondly, the platinum carrying amount of the platinum-carbon catalyst of the hydrogen fuel cell in practical application is generally more than 20 wt%, and the difficulty in manufacturing the high platinum carrying amount catalyst with excellent performance is great. The carbon material is particularly suitable for being used as a platinum-carbon catalyst, can improve the comprehensive performance of the platinum-carbon catalyst, and particularly can be used for preparing a platinum-carbon catalyst with high platinum loading capacity and excellent performance.

And thirdly, the chemical reduction method has simple process, but the utilization rate of platinum is low and the catalytic activity is low. However, the carbon material produced by the present invention is used as a carrier, and a chemical reduction method using an aqueous phase is used, so that a high-platinum-supported catalyst having good specific activity, ECSA and stability can be easily produced.

Fourthly, sulfur is generally considered to generate irreversible toxic action on the platinum catalyst, however, the invention discovers that the catalytic activity and the stability of the platinum-carbon catalyst are remarkably improved by carrying out sulfur-doping modification on the carbon material.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

FIG. 1 is an XPS spectrum of phosphorus for the sulfur-phosphorus doped carbon material of example 1.

FIG. 2 is an XPS spectrum of sulfur for the sulfur-phosphorous doped carbon material of example 1.

FIG. 3 is an XPS spectrum of oxygen for the sulfur and phosphorus doped carbon material of example 1.

FIG. 4 is an XPS spectrum of phosphorus for the sulfur-phosphorus doped carbon material of example 2.

FIG. 5 is an XPS spectrum of sulfur for the sulfur-phosphorous doped carbon material of example 2.

FIG. 6 is an XPS spectrum of phosphorus for the sulfur-phosphorus doped carbon material of example 3.

FIG. 7 is an XPS spectrum of sulfur for the sulfur-phosphorous doped carbon material of example 3.

FIG. 8 is an XPS spectrum of phosphorus for the sulfur and phosphorus doped carbon material of example 4.

FIG. 9 is an XPS spectrum of sulfur for the sulfur-phosphorous doped carbon material of example 4.

FIG. 10 is an XPS spectrum of oxygen for the sulfur and phosphorus doped carbon material of example 4.

Fig. 11 is an XPS spectrum of sulfur for the platinum carbon catalyst of example 5.

Fig. 12 is an XPS spectrum of sulfur for the platinum carbon catalyst of example 6.

Fig. 13 is an XPS spectrum of sulfur of the sulfur-doped carbon material of comparative example 4.

Detailed Description

The present invention will be described in detail with reference to the following embodiments, but it should be understood that the scope of the present invention is not limited by these embodiments and the principle of the present invention, but is defined by the claims.

In the present invention, anything or matters not mentioned is directly applicable to those known in the art without any change except those explicitly described. Moreover, any embodiment described herein may be freely combined with one or more other embodiments described herein, and the technical solutions or ideas formed thereby are considered part of the original disclosure or description of the present invention and should not be considered as new matters not disclosed or contemplated herein, unless a person skilled in the art would consider such combination to be clearly unreasonable.

All of the features disclosed in this application can be combined in any combination which is understood to be disclosed or described in this application and which, unless clearly considered to be too irrational by a person skilled in the art, is to be considered as being specifically disclosed and described in this application. The numerical points disclosed in the present specification include not only the numerical points specifically disclosed in the examples but also the endpoints of each numerical range in the specification, and ranges in which any combination of the numerical points is disclosed or recited should be considered as ranges of the present invention.

Technical and scientific terms used herein are to be defined only in accordance with their definitions, and are to be understood as having ordinary meanings in the art without any definitions.

The "doping element" in the present invention means nitrogen, phosphorus, boron, sulfur, fluorine, chlorine, bromine and iodine.

In the present invention, unless the term "carbon material containing a doping element" is uniquely defined depending on the context or the self-definition, the term "carbon material" refers to a carbon material containing no doping element. So does the underlying concept of carbon material.

In the present invention, "carbon black" and "carbon black" are terms of art that can be substituted for each other.

The "inert gas" in the present invention means a gas which does not have any appreciable influence on the properties of the sulfur-phosphorus doped carbon material in the production process of the present invention. So does the underlying concept of carbon material.

In the present invention, all references to "pore volume" are to P/P, except where the context or self-definition may be clear₀The maximum single point adsorption total pore volume.

The invention provides a sulfur-phosphorus doped carbon material, S analyzed by XPS_2PAmong the peaks, only the peak characteristic to the thiophene type sulfur was observed between 160 to 170 eV.

The sulfur-phosphorus doped carbon material according to the present invention does not contain other doping elements except sulfur and phosphorus.

The sulfur-phosphorus doped carbon material according to the present invention contains no metal element.

According to the sulfur-phosphorus doped carbon material, the characteristic peaks of the thiophene sulfur are double peaks and are respectively located at 163.5 +/-0.5 ev and 164.7 +/-0.5 ev.

Sulfur-phosphorus doped carbon material according to the invention, P analyzed in XPS thereof_2pAmong the spectral peaks, there is a characteristic peak between 125eV and 145eV, which is located at 133.5 eV. + -. 0.5 eV.

The carbon material doped with sulfur and phosphorus according to the present invention has a resistivity of <10.0 Ω · m, preferably <5.0 Ω · m, more preferably <3.0 Ω · m.

According to the sulfur-phosphorus doped carbon material, in XPS analysis, the mass fraction of sulfur is 0.1-5%, and the mass fraction of phosphorus is 0.01-5%; preferably, the mass fraction of sulfur is 0.2-3%, and the mass fraction of phosphorus is 0.02-3%; more preferably, the sulfur mass fraction is 0.3% to 2%. The mass fraction of phosphorus is 0.05-2%.

The specific surface area and pore volume of the carbon material doped with sulfur and phosphorus according to the invention may vary within a wide range, for example the specific surface area may be 10m²/g～2000m²The pore volume may be from 0.02mL/g to 6.0 mL/g. In one embodiment, the specific surface area is 200m²/g～2000m²The pore volume is 0.2mL/g to 3.0 mL/g.

According to the sulfur-phosphorus doped carbon material, the sulfur-phosphorus doped carbon material is sulfur-phosphorus doped graphene, sulfur-phosphorus doped carbon nano tubes or sulfur-phosphorus doped conductive carbon black.

According to the sulfur-phosphorus doped carbon material, the Conductive carbon black can be common Conductive carbon black (Conductive Blacks), Super Conductive carbon black (Super Conductive Blacks) or Extra Conductive carbon black (Extra Conductive Blacks), for example, the Conductive carbon black can be one or more of Ketjen black series superconducting carbon black, Cabot series Conductive carbon black and series Conductive carbon black produced by Wingda Texas company; preferably Ketjen Black EC-300J, Ketjen Black EC-600JD, Ketjen Black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

The sulfur-phosphorus doped carbon material has no limitation on the preparation method and the source of the conductive carbon black. The conductive carbon black may be acetylene black, furnace black, or the like.

According to the sulfur-phosphorus doped carbon material of the present invention, sulfur and phosphorus are bonded to the carbon material in the form of chemical bonds.

Sulfur-phosphorus doped carbon material according to the invention, O analyzed in XPS thereof_1sAmong the spectral peaks, there is a symmetrical peak between 530ev and 535 ev.

The invention also provides a preparation method of the sulfur-phosphorus doped carbon material, which comprises the following steps:

According to the preparation method of the sulfur-phosphorus doped carbon material, in the steps (1) and (2), the temperature is raised if necessary, and the temperature raising rate is 1-20 ℃/min respectively, preferably 3-15 ℃/min, more preferably 8-15 ℃/min.

According to the method for producing a sulfur-phosphorus doped carbon material of the present invention, there is no particular limitation on the phosphorus source, and any phosphorus source that can be used in the art for doping a carbon material may be used in the present invention. The phosphorus source can be one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogen phosphate, dihydrogen phosphate, phosphite and hypophosphite.

According to the preparation method of the sulfur-phosphorus doped carbon material, the mass of the phosphorus source is calculated according to the mass of phosphorus contained in the phosphorus source, and the mass ratio of the carbon material to the phosphorus source is 10000: 1-20: 1; preferably 2500: 1-30: 1.

according to the preparation method of the sulfur-phosphorus doped carbon material, the sulfur source is elemental sulfur.

According to the preparation method of the sulfur-phosphorus doped carbon material, the mass of the sulfur source is calculated by the mass of the sulfur contained in the carbon material, and the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1; preferably 10: 1-4: 1, more preferably 8: 1-4: 1.

according to the preparation method of the sulfur-phosphorus doped carbon material, in the step (1), the temperature is 400-600 ℃.

According to the preparation method of the sulfur-phosphorus doped carbon material, in the step (2), the temperature can be 400-600 ℃, 600-1000 ℃ or 1000-1500 ℃.

According to the preparation method of the sulfur-phosphorus doped carbon material, (1) and (2), the treatment time is 1-5 h, preferably 2-4 h.

According to the preparation method of the sulfur-phosphorus doped carbon material, the carbon material can be carbon nano tubes, conductive carbon black or graphene. The conductive carbon black is one or more of Ketjen black series superconducting carbon black, Cabot series conductive carbon black and series conductive carbon black produced by Wingchuang Texaco company; preferably EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

According to the preparation method of the sulfur-phosphorus doped carbon material, I of the carbon material in (1)_D/I_GThe value is generally 0.8 to 5, preferably 1 to 4. In the Raman spectrum, it is located at 1320cm^-1The nearby peak is the D peak and is located at 1580cm^-1The nearby peak is the G peak, I_DRepresents the intensity of the D peak, I_GRepresenting the intensity of the G peak.

According to the preparation method of the sulfur-phosphorus doped carbon material, the inert gas is nitrogen or argon.

According to the method for producing a sulfur-phosphorus doped carbon material of the present invention, the carbon material in (1) has a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <2 Ω · m.

According to the preparation method of the sulfur-phosphorus doped carbon material, in XPS analysis of the carbon material in (1), the oxygen mass fraction is generally more than 4%, and preferably 4-15%.

According to the preparation method of the sulfur-phosphorus doped carbon material, the specific surface area of the carbon material in (1) can be changed in a large range. Generally, the specific surface area is 10m²/g～2000m²(ii)/g; the pore volume is 0.02 mL/g-6 mL/g.

According to the preparation method of the sulfur-phosphorus doped carbon material, in the step (1), the carbon material is contacted with a phosphorus source in the following way: the carbon material is impregnated in an aqueous solution of a phosphorus source and then dried.

According to the preparation method of the sulfur-phosphorus doped carbon material, (2), the contact mode of the phosphorus doped carbon material and a sulfur source is as follows: the phosphorus doped carbon material is mixed with elemental sulphur.

According to the method for preparing the sulfur-phosphorus doped carbon material, a metal-containing catalyst is not used in the process of preparing the sulfur-phosphorus doped carbon material.

A sulfur-phosphorus doped carbon material is prepared by any one of the methods.

The sulfur-phosphorus doped carbon material is applied to electrochemistry as an electrode material.

A platinum-carbon catalyst comprises a carbon carrier and platinum metal loaded on the carbon carrier, wherein the carbon carrier is a sulfur-phosphorus doped carbon material; s analyzed in XPS of the platinum-carbon catalyst_2PAmong the peaks, only the peak characteristic to the thiophene type sulfur was observed between 160 to 170 eV.

The platinum-carbon catalyst according to the present invention does not contain doping elements other than sulfur and phosphorus.

The platinum-carbon catalyst according to the present invention does not contain other metal elements than platinum.

According to the platinum-carbon catalyst of the present invention, sulfur and phosphorus are chemically bonded to the carbon material in the carbon support.

The platinum-carbon catalyst according to the present invention, its XPS analyzed P_2pAmong the spectral peaks, there was no characteristic peak between 125 to 145 eV.

According to the platinum-carbon catalyst, the sulfur-phosphorus doped carbon material is sulfur-phosphorus doped graphene, sulfur-phosphorus doped carbon nano tubes or sulfur-phosphorus doped conductive carbon black.

According to the platinum carbon catalyst of the invention, the conductive carbon black can be one or more of Ketjen black series superconducting carbon black, Cabot series conductive carbon black and series conductive carbon black produced by Wingda Gusai company; preferably Ketjen Black EC-300J, Ketjen Black EC-600JD, Ketjen Black ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

The preparation method and the source of the conductive carbon black are not limited by the platinum carbon catalyst. The conductive carbon black may be acetylene black, furnace black, or the like.

According to the platinum-carbon catalyst of the present invention, the mass fraction of platinum is 0.1% to 80%, preferably 20% to 70%, and more preferably 40% to 70% based on the mass of the catalyst.

The platinum-carbon catalyst according to the invention has a resistivity of <10.0 Ω · m, preferably <2.0 Ω · m.

According to the platinum-carbon catalyst of the present invention, the specific surface area of the platinum-carbon catalyst is 80m²/g～1500m²A/g, preferably of 100m²/g～200m²/g。

According to the platinum-carbon catalyst of the invention, a phosphorus signal (P, P) is detected in a TG-MS (thermogravimetric-mass spectrometry) test₂O₃And P₂O₅)。

The invention provides a preparation method of a platinum-carbon catalyst, which comprises the following steps:

According to the preparation method of the platinum-carbon catalyst, the temperature is raised in the steps (1) and (2) as required, and the temperature raising rate is 1-20 ℃/min, preferably 3-15 ℃/min, and more preferably 8-15 ℃/min.

According to the preparation method of the platinum-carbon catalyst, the phosphorus source is one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogen phosphate, dihydrogen phosphate, phosphite and hypophosphite.

According to the preparation method of the platinum-carbon catalyst, in the step (1), the mass of the phosphorus source is calculated according to the mass of phosphorus contained in the carbon material, and the mass ratio of the carbon material to the phosphorus source is 10000: 1-20: 1; preferably 2500: 1-30: 1.

according to the preparation method of the platinum-carbon catalyst, the sulfur source is elemental sulfur.

According to the preparation method of the platinum-carbon catalyst, in the step (2), the mass of the sulfur source is calculated by the mass of sulfur contained in the carbon material, and the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1; preferably 10: 1-4: 1, more preferably 8: 1-4: 1.

according to the preparation method of the platinum-carbon catalyst, in the step (1), the temperature is 400-600 ℃.

According to the preparation method of the platinum-carbon catalyst, in the step (2), the temperature can be 400-600 ℃, 600-1000 ℃ or 1000-1500 ℃.

According to the preparation method of the platinum-carbon catalyst of the invention, in (1) and (2), the treatment time is 1h to 5h, preferably 2h to 4 h.

According to the preparation method of the platinum-carbon catalyst, the carbon material is graphene, conductive carbon black or carbon nanotubes. The conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

According to the preparation method of the platinum-carbon catalyst, in the step (1), in XPS analysis of the carbon material, the oxygen mass fraction is more than 4%, and preferably 4-15%.

According to the method for producing a platinum-carbon catalyst of the present invention, (1), the carbon material has a resistivity of <10 Ω · m, preferably <5 Ω · m, and more preferably <2 Ω · m.

According to the preparation method of the platinum-carbon catalyst of the present invention, in (1), the carbon material has a specific surface area of 10m²/g～2000m²A/g, preferably of 200m²/g～2000m²(ii)/g; the pore volume is 0.02mL/g to 6mL/g, preferably 0.2mL/g to 3 mL/g.

According to the preparation method of the platinum-carbon catalyst of the invention, in the step (1), the carbon material is contacted with the phosphorus source in the following way: the carbon material is impregnated in an aqueous solution of a phosphorus source and then dried.

According to the preparation method of the platinum-carbon catalyst of the invention, in the step (2), the phosphorus-doped carbon material is contacted with the sulfur source in the following manner: the phosphorus doped carbon material is mixed with elemental sulphur.

According to the preparation method of the platinum-carbon catalyst of the present invention, the step of supporting platinum comprises:

(b) adding a reducing agent for reduction;

According to the preparation method of the platinum-carbon catalyst, in the step (a), the platinum precursor is chloroplatinic acid, potassium chloroplatinate or sodium chloroplatinate; the concentration of the platinum precursor is 0.5-5 mol/L.

According to the preparation method of the platinum-carbon catalyst, in the step (b), the reducing agent is one or more 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 2-100; the reduction temperature is 60-90 ℃; the reduction time is 4-15 h.

A platinum-carbon catalyst is prepared by any one of the preparation methods of the platinum-carbon catalyst.

A hydrogen fuel cell using any one of the above sulfur-phosphorus doped carbon materials or any one of the above platinum-carbon catalysts in the anode and/or the cathode thereof.

The present invention will be described in detail with reference to specific examples. The following examples will assist those skilled in the art in further understanding the invention, but are not intended to limit the invention in any way.

Reagents, instruments and tests

Unless otherwise specified, all reagents used in the invention are analytically pure, and all reagents are commercially available.

The invention detects elements on the surface of the material by an X-ray photoelectron spectrum analyzer (XPS). The adopted X-ray photoelectron spectrum analyzer is prepared by VG scientific companyAn ESCALB 220i-XL type ray electron spectrometer with Avantage V5.926 software, wherein the X-ray photoelectron spectroscopy analysis test conditions are as follows: the excitation source is monochromatized A1K alpha X-ray, the power is 330W, and the basic vacuum is 3X 10 during analysis and test^-9mbar. In addition, the electron binding energy was corrected with the C1s peak (284.3eV) of elemental carbon, and the late peak processing software was XPSPEAK. The characteristic peak of the thiophene sulfur in the spectrogram is the characteristic peak after peak separation.

Apparatus and method of elemental analysis, conditions: an element analyzer (Vario EL Cube), the reaction temperature is 1150 ℃, 5mg of the sample is weighed, the reduction temperature is 850 ℃, the flow rate of carrier gas helium is 200mL/min, the flow rate of oxygen is 30mL/min, and the oxygen introducing time is 70 s.

The instrument, the method and the conditions for testing the mass fraction of platinum in the platinum-carbon catalyst are as follows: and (3) adding 30mL of aqua regia into 30mg of the prepared Pt/C catalyst, condensing and refluxing for 12h at 120 ℃, cooling to room temperature, taking supernatant liquid for dilution, and testing the Pt content in the supernatant liquid by using ICP-AES (inductively coupled plasma-atomic emission Spectrometry).

The high-resolution transmission electron microscope (HRTEM) adopted by the invention is JEM-2100(HRTEM) (Nippon electronics Co., Ltd.), and the test conditions of the high-resolution transmission electron microscope are as follows: the acceleration voltage was 200 kV. The particle size of the nanoparticles in the sample is measured by an electron microscope picture.

BET test method: in the invention, the pore structure property of a sample is measured by a Quantachrome AS-6B type analyzer, the specific surface area and the pore volume of the catalyst are obtained by a Brunauer-Emmett-Taller (BET) method, and the pore distribution curve is obtained by calculating a desorption curve according to a Barrett-Joyner-Halenda (BJH) method.

The Raman detection adopts a LabRAM HR UV-NIR laser confocal Raman spectrometer produced by HORIBA company of Japan, and the laser wavelength is 532 nm.

Electrochemical performance test, instrument Model Solartron analytical energy lab and Princeton Applied Research (Model 636A), methods and test conditions: polarization curve LSV of catalyst at 1600rpm₂Saturated 0.1M HClO₄Test in (1), CV Curve under Ar atmosphere 0.1M HClO₄To calculate the electrochemically active area ECSA. At O in the stability test₂Saturated 0.1M HClO₄After 5000 cycles of scanning in the range of 0.6V to 0.95V, LSV and ECSA were tested as described above. During the test, the catalyst is prepared into evenly dispersed slurry and coated on a glassy carbon electrode with the diameter of 5mm, and the platinum content of the catalyst on the electrode is 3-4 mu g.

Resistivity test four-probe resistivity tester, instrument model KDY-1, method and test conditions: the applied pressure is 3.9 plus or minus 0.03MPa, and the current is 500 plus or minus 0.1 mA.

TG-MS test: the test is carried out by adopting a German Chiz-resistant STA449F5-QMS403D type thermogravimetric-mass spectrometer, an ion source is an EI source, a quadrupole mass spectrometer adopts an MID mode, a transmission pipeline is a capillary tube with the length of 3 meters, and the temperature is 260 ℃; the temperature range is 55-1000 ℃, and the heating rate is 10 ℃/min.

VXC72(Vulcan XC72, produced by Kabot, USA) was purchased from Suzhou wingong sandisk energy science and technology, Inc. The results of the tests by the instrument method show that: specific surface area 258m²Per g, pore volume 0.388mL/g, oxygen mass fraction 8.72%, I_D/I_G1.02, and a resistivity of 1.22. omega. m.

Ketjenblack ECP600JD (manufactured by Lion corporation, japan) was purchased from tsuzhou wingong sandisk energy science and technology limited. The results of the tests by the instrument method show that: specific surface area 1362m²G, pore volume 2.29mL/g, oxygen mass fraction 6.9%, I_D/I_G1.25, and resistivity of 1.31. omega. m.

Commercial platinum carbon catalyst (trade name HISPEC4000, manufactured by Johnson Matthey corporation) was purchased from Alfa Aesar. The test result shows that: the mass fraction of platinum was 40.2%.

Example 1

This example illustrates a sulfur-phosphorus doped carbon material according to the present invention.

1g of Vulcan XC72 was immersed in 15mL of a 4.0 wt% aqueous phosphoric acid solution for 16 h; drying in an oven at 100 ℃; and then placing the mixture into a tube furnace, heating the tube furnace to 400 ℃ at the speed of 10 ℃/min, carrying out constant temperature treatment for 3h, and naturally cooling to obtain the phosphorus-doped carbon material.

Uniformly mixing the phosphorus-doped carbon material with 0.167g of elemental sulfur, putting the mixture into a tubular furnace, heating the tubular furnace to 400 ℃ at the speed of 8 ℃/min, and carrying out constant-temperature treatment for 3 hours; and naturally cooling to obtain the sulfur-phosphorus doped carbon material.

Sample characterization and testing

The sulfur-phosphorus doped carbon material of the embodiment has a sulfur mass fraction of 1.44% by XPS analysis; the mass fraction of phosphorus analyzed by XPS was 1.57%; the specific surface area is 239m²(ii)/g; the resistivity was 1.31. omega. m.

Example 2

1g of Vulcan XC72 was immersed in 15mL of 4.8 wt% aqueous sodium phosphate solution for 24 h; drying in an oven at 100 ℃; and then putting the mixture into a tube furnace, heating the tube furnace to 400 ℃ at the speed of 8 ℃/min, carrying out constant temperature treatment for 3h, and naturally cooling to obtain the phosphorus-doped carbon material.

Uniformly mixing the phosphorus-doped carbon material with 0.2g of elemental sulfur, putting the mixture into a tubular furnace, heating the tubular furnace to 1400 ℃ at the speed of 8 ℃/min, and carrying out constant-temperature treatment for 3 hours; and naturally cooling to obtain the sulfur-phosphorus doped carbon material numbered as a carbon carrier A.

Sample characterization and testing

In the sulfur-phosphorus doped carbon material in the embodiment, the sulfur mass fraction analyzed by XPS is 0.97%; the mass fraction of phosphorus analyzed by XPS was 0.55%; specific surface area of 231m²(ii)/g; the resistivity was 1.27. omega. m.

Example 3

Adding 10mL of absolute ethanol into 1g of Ketjenblack ECP600JD, and then adding 25mL of 1.8 wt% phosphoric acid aqueous solution for impregnation for 24 h; drying in an oven at 100 ℃; and then placing the mixture into a tube furnace, heating the tube furnace to 600 ℃ at the speed of 10 ℃/min, carrying out constant temperature treatment for 3h, and naturally cooling to obtain the phosphorus-doped carbon material.

Uniformly mixing the phosphorus-doped carbon material with 0.15g of elemental sulfur, putting the mixture into a tubular furnace, heating the tubular furnace to 700 ℃ at the speed of 10 ℃/min, and carrying out constant-temperature treatment for 3 hours; and naturally cooling to obtain the sulfur-phosphorus doped carbon material.

Sample characterization and testing

The sulfur-phosphorus doped carbon material has the sulfur mass fraction of 1.41 percent through XPS analysis; the mass fraction of phosphorus analyzed by XPS was 0.18%; the specific surface area is 1325m²(ii)/g; the resistivity was 1.37. omega. m.

Example 4

Adding 10mL of absolute ethanol into 1g of Ketjenblack ECP600JD, and then adding 25mL of 1 wt% sodium phosphate aqueous solution for soaking for 16 h; drying in an oven at 100 ℃; and then placing the mixture into a tube furnace, heating the tube furnace to 600 ℃ at the speed of 10 ℃/min, carrying out constant temperature treatment for 3h, and naturally cooling to obtain the phosphorus-doped carbon material.

Uniformly mixing the phosphorus-doped carbon material with 0.25g of elemental sulfur, putting the mixture into a tubular furnace, heating the tubular furnace to 1200 ℃ at the speed of 10 ℃/min, and carrying out constant-temperature treatment for 3 hours; and naturally cooling to obtain the sulfur-phosphorus doped carbon material numbered as a carbon carrier B.

Sample characterization and testing

The sulfur-phosphorus doped carbon material has the sulfur mass fraction of 1.06 percent through XPS analysis; the mass fraction of phosphorus analyzed by XPS was 0.11%; the specific surface area is 1306m²(ii)/g; the resistivity was 1.35. omega. m.

Example 5

This example serves to illustrate the platinum carbon catalyst of the present invention.

Dispersing a carbon carrier A into deionized water according to the proportion that 250mL of water is used for each gram of carbon carrier, adding 3.4mmol of chloroplatinic acid into each gram of carbon carrier, performing ultrasonic dispersion to form a suspension, and adding 1mol/L of sodium carbonate aqueous solution to enable the pH value of the system to be 10; heating the suspension to 80 ℃, adding formic acid to carry out reduction reaction while stirring, wherein the molar ratio of the formic acid to the chloroplatinic acid is 50:1, and continuously maintaining the reaction for 10 hours; and filtering the reacted mixture, washing the mixture by deionized water until the pH value of the filtrate is neutral, filtering the mixture, and drying the filtrate at 100 ℃ to obtain the platinum-carbon catalyst.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 40.2%.

No P was found in XPS analysis of the platinum-carbon catalyst between 125eV and 145eV_2pCharacteristic peak of (2).

Detection of P, P in TG-MS test₂O₃And P₂O₅Of the signal of (1).

The results of the platinum carbon catalyst performance tests are shown in table 1.

Example 6

Dispersing a carbon carrier B into deionized water according to the proportion that 250mL of water is used for each gram of carbon carrier, adding 12mmol of chloroplatinic acid into each gram of carbon carrier, performing ultrasonic dispersion to form a suspension, and adding 1mol/L of potassium hydroxide aqueous solution to adjust the pH value of the system to 10; heating the suspension to 80 ℃, adding sodium phosphine under stirring for reduction reaction, wherein the molar ratio of the reducing agent to the platinum precursor is 5:1, and maintaining the reaction for 12 hours; and filtering the reacted mixture, washing until the pH value of the solution is neutral, and drying at 100 ℃ to obtain the carbon-supported platinum catalyst.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 69.8%.

Detection of P, P in TG-MS test₂O₃And P₂O₅Of the signal of (1).

Comparative example 1

Dispersing Vulcan XC72 in deionized water according to the proportion that each gram of carbon carrier uses 250mL of water, adding 3.4mmol of chloroplatinic acid into each gram of carbon carrier, performing ultrasonic dispersion to form suspension, and adding 1mol/L of sodium carbonate aqueous solution to ensure that the pH value of the system is 10; heating the suspension to 80 ℃, adding formic acid to carry out reduction reaction while stirring, wherein the molar ratio of the formic acid to the chloroplatinic acid is 50:1, and continuously maintaining the reaction for 10 hours; and filtering the reacted mixture, washing the mixture by deionized water until the pH value of the filtrate is neutral, filtering the mixture, and drying the filtrate at 100 ℃ to obtain the platinum-carbon catalyst.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 40.1%.

Comparative example 2

Dispersing Ketjenblack ECP600JD according to the proportion of 200mL of water to 50mL of ethanol used for each gram of carbon carrier, adding 12mmol of chloroplatinic acid into each gram of carbon carrier, performing ultrasonic dispersion to form a suspension, and adding 1mol/L of potassium hydroxide aqueous solution to adjust the pH value of the system to 10; heating the suspension to 80 ℃, adding sodium phosphine under stirring for reduction reaction, wherein the molar ratio of the reducing agent to the platinum precursor is 5:1, and maintaining the reaction for 12 hours; and filtering the reacted mixture, washing until the pH value of the solution is neutral, and drying at 100 ℃ to obtain the carbon-supported platinum catalyst.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 69.7%.

Comparative example 3

The platinum carbon catalyst was a commercial catalyst purchased under the designation HISPEC 4000.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 40.2%.

Comparative example 4

Mixing Vulcan XC72 and elemental sulfur uniformly, wherein the mass ratio of the Vulcan XC72 to the elemental sulfur is 6: 1, placing the carbon material in a tube furnace, heating the tube furnace to 400 ℃ at the speed of 8 ℃/min, then carrying out constant temperature treatment for 3h, and naturally cooling to obtain the sulfur-doped carbon material.

Sample characterization and testing

TABLE 1

Claims

2. The sulfur-phosphorus doped carbon material as claimed in claim 1, wherein P is analyzed by XPS_2pAmong the spectral peaks, there is a characteristic peak between 125eV and 145 eV.

3. The sulfur-phosphorus doped carbon material as claimed in claim 1, wherein the sulfur content is 0.1 to 5% by mass and the phosphorus content is 0.01 to 5% by mass in XPS analysis.

4. The sulfur-phosphorus doped carbon material according to claim 1, wherein the sulfur-phosphorus doped carbon material is sulfur-phosphorus doped graphene, sulfur-phosphorus doped carbon nanotubes or sulfur-phosphorus doped conductive carbon black.

5. The carbon material of claim 4, wherein the conductive carbon Black is EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXAXK 40B 2.

6. A preparation method of a sulfur-phosphorus doped carbon material comprises the following steps:

7. The method according to claim 6, wherein the phosphorus source is one or more selected from phosphoric acid, phosphates, pyrophosphates, polyphosphates, hydrogenphosphates, dihydrogenphosphates, phosphites and hypophosphites.

8. The production method according to claim 6, wherein the mass ratio of the carbon material to the phosphorus source is 10000: 1-20: 1.

9. the method according to claim 6, wherein the sulfur source is elemental sulfur.

10. The production method according to claim 6, wherein the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1.

11. the process according to claim 6, wherein the temperature in (2) is 1000 ℃ to 1500 ℃.

12. The method according to claim 6, wherein the carbon material in (1) has a specific resistance<10 omega. m, specific surface area of 10m²/g～2000m²(iv)/g, XPS analysis oxygen mass fraction greater than 4%.

13. The method according to claim 6, wherein the carbon material is contacted with the phosphorus source in the following manner in (1): the carbon material is impregnated in an aqueous solution of a phosphorus source and then dried.

14. A sulfur-phosphorus doped carbon material characterized by being produced by the method of any one of claims 6 to 13.

15. Use of the sulfur-phosphorus doped carbon material as claimed in any one of claims 1 to 5 and 14 as an electrode material in electrochemistry.

16. The platinum-carbon catalyst is characterized by comprising a carbon carrier and platinum metal loaded on the carbon carrier, wherein the carbon carrier is a sulfur-phosphorus doped carbon material; XPS analyzed S of the platinum carbon catalyst_2PAmong the peaks, only the peak characteristic to the thiophene type sulfur was observed between 160 to 170 eV.

17. Platinum-carbon catalyst according to claim 16, characterised in that P is analysed in its XPS_2pAmong the spectral peaks, there was no characteristic peak between 125 to 145 eV.

18. A method of preparing a platinum carbon catalyst comprising:

(1) a step of producing a phosphorus-doped carbon material: contacting a carbon material with a phosphorus source, and treating for 0.5-10 h at 300-800 ℃ in an inert gas to obtain a phosphorus-doped carbon material; and

19. The method for preparing a platinum-carbon catalyst according to claim 18, wherein the step of supporting platinum comprises:

(a) dispersing the sulfur-phosphorus doped carbon material obtained in the step (2) and a platinum precursor in a water phase, and adjusting the pH to 8-12;

(b) adding a reducing agent for reduction;

20. The method for preparing a platinum-carbon catalyst according to claim 19, wherein in (a), the platinum precursor is chloroplatinic acid, potassium chloroplatinate, or sodium chloroplatinate; the concentration of the platinum precursor is 0.5-5 mol/L.

21. The method for preparing a platinum-carbon catalyst according to claim 19, wherein in (b), the reducing agent is one or more 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 2-100; the reduction temperature is 60-90 ℃; the reduction time is 4-15 h.

22. A platinum carbon catalyst, characterized in that it is obtainable by a process according to any one of claims 18 to 21.

23. A hydrogen fuel cell characterized in that the platinum-carbon catalyst of claim 16 or 22 is used in the anode and/or the cathode of the hydrogen fuel cell.