CN114497599A

CN114497599A - Sulfur nitrogen phosphorus boron doped carbon material, platinum carbon catalyst, and preparation method and application thereof

Info

Publication number: CN114497599A
Application number: CN202011152364.3A
Authority: CN
Inventors: 赵红; 荣峻峰; 顾贤睿; 张家康; 彭茜; 王厚朋; 张云阁; 谢南宏
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: 2020-10-26
Filing date: 2020-10-26
Publication date: 2022-05-13
Anticipated expiration: 2040-10-26
Also published as: CN114497599B

Abstract

The invention relates to a sulfur nitrogen phosphorus boron doped carbon material, a platinum carbon catalyst, and a preparation method and application thereof. In XPS analysis of the carbon material doped with sulfur, nitrogen, phosphorus, boron and carbon, only the characteristic peak of thiophene sulfur exists between 160eV and 170 eV. The fuel cell platinum-carbon catalyst using the sulfur-nitrogen-phosphorus-boron-carbon doped carbon material as the carrier, in particular to a platinum-carbon catalyst with high platinum loading, has excellent catalytic performance and carbon corrosion resistance.

Description

Sulfur nitrogen phosphorus boron doped carbon material, platinum carbon catalyst, and preparation method and application thereof

Technical Field

The invention relates to a sulfur nitrogen phosphorus boron doped carbon material, a platinum carbon catalyst using the carbon material as a carrier, and preparation methods and applications of the carbon material and the platinum carbon catalyst.

Background

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 so as to obtain more suitable 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. Although there are many reports of the direct use of doped carbon materials as fuel cell catalysts and some research results show better activity, there is a wide gap and distance from commercial use compared to platinum carbon catalysts. On the one hand, the knowledge of the bonding mode of the heteroatom and the carbon material, the interaction between the heteroatoms and the catalytic mechanism is not sufficient in the field; on the other hand, each heteroatom has multiple bonding modes with the carbon material, and multiple functions exist among the heteroatoms, so that the situation is very complicated when multiple heteroatoms are doped, and therefore, how to control the bonding modes and the interactions among the heteroatoms and the carbon material is difficult for doping atoms. In addition, such catalysts are generally not suitable for acidic environments, especially for important Proton Exchange Membrane Fuel Cells (PEMFCs).

To date, the most effective oxygen reduction catalyst is the platinum carbon catalyst, but the platinum carbon catalyst still has deficiencies for large scale commercial applications. On the one hand, platinum is scarce and expensive, and the cost thereof accounts for about 40% of the total cost of the fuel cell. On the other hand, the currently used commercial platinum-carbon catalyst has undesirable platinum metal dispersion and is easy to agglomerate and deactivate, and the platinum surface area of the hydrogen fuel cell cathode is obviously reduced along with the time due to platinum dissolution and agglomeration, so that the service life of the fuel cell is influenced. It is highly desirable in the art to greatly increase the utilization of platinum metal and to increase its catalytic activity and stability in order 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 of improving the performance of platinum carbon catalysts by modifying the carbon support.

The carbon carrier can improve the specific surface area of the catalyst, reduce the agglomeration of metal particles and improve the metal utilization rate. The platinum-carrying amount of the carbon carrier is increased, so that a thinner membrane electrode with better performance can be manufactured, but the platinum-carrying amount is greatly increased, 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. In addition, the platinum loading capacity 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 capacity is less than 5 wt%).

The problem of deactivation of platinum carbon catalysts due to carbon corrosion in proton exchange membrane fuel cells has attracted a great deal of attention in the art. It is reported in the literature that, theoretically, when the potential is more than 0.2V, corrosion of the carbon support occurs. In practice, the problem of carbon corrosion is only obvious when the potential is greater than 1.2V. When the battery is in open-circuit operation, the cathode potential can be higher than 0.9V, and in the starting/stopping process of the battery, the cathode local interface potential can even reach 1.6V, so that the carbon corrosion reaction is greatly accelerated, and the performance of the platinum-carbon catalyst is sharply reduced. In addition, platinum also accelerates the carbon corrosion rate, with greater amounts of platinum loading causing faster carbon corrosion. The conductive carbon black is low in price and is a platinum carbon catalyst carrier used in industry, but the corrosion resistance of the conductive carbon black is poor. On the one hand, the carbon carrier has a large number of defect sites, which is beneficial to increasing the platinum carrying amount, but at the same time, the carbon corrosion is intensified. On the other hand, increasing the degree of graphitization alleviates carbon corrosion, but also renders the surface of the carbon support chemically inert, making it difficult to uniformly disperse platinum on the carbon support.

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 carbon material having unique properties and a simple process for its preparation. The second purpose of the invention is to improve the carbon corrosion resistance of the platinum-carbon catalyst on the basis of the carbon material. The third object of the present invention is to provide a platinum-carbon catalyst having more excellent overall performance and a simple process for producing the same, based on the aforementioned objects. It is a fourth object of the present invention to provide a platinum-carbon catalyst with a higher platinum loading in addition to the aforementioned objects.

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

1. A sulfur nitrogen phosphorus boron doped carbon material characterized in that S is analyzed by XPS_2PAmong the peaks, there is only a characteristic peak of thiophene-type sulfur between 160eV and 170 eV.

2. A S, N, P, B doped carbon material according to any one of the preceding claims characterised in that N is analysed by XPS_1sAmong the peaks, the peak area between 399eV and 400.5eV is 70% or more, preferably 80% or more, more preferably 90% or more of the total area of the peak between 390eV and 410 eV.

3. A sulfur, nitrogen, phosphorus and boron doped carbon material according to any one of the preceding claims, characterized in that B is analyzed by XPS_1sAmong the peaks, there is a characteristic peak between 189eV and 191.5 eV.

4. A sulfur, nitrogen, phosphorus and boron doped carbon material according to any one of the preceding claims, characterized in that B is analyzed by XPS_1sAmong the spectrum peaks, there are two characteristic peaks between 189ev and 191.5 ev.

5. A S, N, P, B doped carbon material according to any one of the preceding claims characterised in that P is analysed by XPS_2PAmong the spectral peaks, there are two characteristic peaks between 133.5eV and 135.5 eV.

6. The carbon material doped with sulfur, nitrogen, phosphorus and boron is characterized in that in XPS analysis, the mass fraction of sulfur is 0.01-6%, the mass fraction of nitrogen is 0.01-8%, the mass fraction of phosphorus is 0.01-6%, and the mass fraction of boron is 0.01-6%; preferably, the mass fraction of sulfur is 0.1-2%, preferably the mass fraction of nitrogen is 0.1-4%, preferably the mass fraction of phosphorus is 0.1-4%, preferably the mass fraction of boron is 0.1-4%.

7. The carbon material doped with boron, sulfur, nitrogen, phosphorus and the like according to any one of the above, characterized by having a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <3 Ω · m.

8. A sulfur, nitrogen, phosphorus and boron 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.

9. A sulphur nitrogen phosphorus boron doped carbon material according to any preceding claim, 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.

10. A method of doping a carbon material comprising: (1) firstly, contacting a carbon material with a phosphorus source and a boron source, and treating (preferably treating at constant temperature) for 0.5-10 h at 300-800 ℃ in inert gas; (2) then contacting with a sulfur source and a nitrogen source, and treating in inert gas at 400-1000 ℃ for 0.5-10 h (preferably constant temperature treatment).

11. The method for doping a carbon material according to any one of the preceding claims, wherein 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.

12. the method for doping a carbon material as set forth in any of the preceding claims, wherein the mass ratio of the carbon material to the nitrogen source is 500: 1-5: 1; preferably 200: 1-10: 1.

13. the method for doping a carbon material according to any one of the preceding claims, wherein the mass ratio of the carbon material to the phosphorus source is 10000: 1-10: 1; preferably 2000: 1-20: 1.

14. the method for doping a carbon material according to any one of the preceding claims, wherein the mass ratio of the carbon material to the boron source is 10000: 1-10: 1; preferably 2000: 1-20: 1.

15. a method for doping a carbon material as recited in any of the preceding claims, wherein said sulfur source is elemental sulfur.

16. The method for doping a carbon material according to any one of the preceding claims, wherein the nitrogen source is ammonia water or urea.

17. The method for doping a carbon material according to any one of the preceding claims, wherein the phosphorus source is one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogenphosphate, dihydrogenphosphate, phosphite and hypophosphite.

18. The method for doping a carbon material according to any one of the preceding claims, wherein the boron source is one or more of boric acid and borate.

19. The method for doping a carbon material according to any one of the above items (1) and (2), wherein the treatment time is 1 to 5 hours, preferably 2 to 4 hours, independently of each other.

20. The method for doping a carbon material according to any one of the above items, wherein the temperature in (1) is 450 to 700 ℃.

21. The method for doping a carbon material according to any one of the above items, wherein the temperature in (2) is 550 to 900 ℃.

22. The method for doping a carbon material according to any one of the preceding claims, wherein the carbon material is graphene, carbon nanotubes or conductive carbon black; the conductive carbon Black is preferably EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

23. The method for doping a carbon material as set forth in any one of the preceding claims, wherein the carbon material has an oxygen mass fraction of more than 4%, preferably 4% to 15%, in XPS analysis.

24. The method for doping a carbon material according to any of the above, wherein the carbon material has a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <2 Ω · m.

25. The method for doping a carbon material as recited in any one of the above, wherein the carbon material has a specific surface area of 10m²/g～2000m²A/g, preferably of 200m²/g～2000m²(iv) g; the pore volume is 0.02mL/g to 6mL/g, preferably 0.2mL/g to 3 mL/g.

26. The carbon material doped with boron, nitrogen, phosphorus and sulfur prepared by the method for doping the carbon material.

27. The sulfur nitrogen phosphorus boron doped carbon material is applied to electrochemistry as an electrode material.

28. The platinum-carbon catalyst comprises a carbon carrier and platinum metal loaded on the carbon carrier, and is characterized in that the carbon carrier is a sulfur-nitrogen-phosphorus-boron doped carbon material, and S analyzed by XPS (X-ray diffraction) of the platinum-carbon catalyst_2PAmong the peaks, there is only a characteristic peak of thiophene-type sulfur between 160eV and 170 eV.

29. A platinum-carbon catalyst according to any one of the preceding claims, N as analyzed by XPS thereof_1sIn the spectrum peak, except that the characteristic peak area exists between 399eV and 400.5eV, other characteristic peaks do not exist between 390eV and 410 eV.

30. The platinum-carbon catalyst according to any one of the preceding claims, characterized in that in its XPS analysis there is no B between 185 and 200eV_1sAnd no P between 125ev and 145ev_2pCharacteristic peak of (2).

31. The platinum-carbon catalyst according to any one of the preceding claims, characterized in that the carbon material is graphene, carbon nanotubes or conductive carbon black; the conductive carbon Black is preferably EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

32. 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.

33. The platinum-carbon catalyst according to any one of the above, wherein the carbon carrier is a sulfur-nitrogen-phosphorus-boron-doped carbon material.

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

(1) a step of manufacturing a carbon support: firstly, contacting a carbon material with a phosphorus source and a boron source, and treating (preferably treating at constant temperature) for 0.5-10 h at 300-800 ℃ in inert gas; then contacting with a sulfur source and a nitrogen source, and treating (preferably treating at constant temperature) for 0.5-10 h at 400-1000 ℃ in inert gas to obtain the carbon carrier;

(2) a step of supporting platinum with the carbon carrier obtained in (1).

35. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, characterized in that in (1), the sulfur source is elemental sulfur.

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

37. the process for producing a platinum-carbon catalyst according to any one of the preceding claims, wherein in (1), the nitrogen source is ammonia water or urea.

38. The method for preparing any one of the platinum-carbon catalysts described above, wherein in (1), the mass ratio of the carbon material to the nitrogen source, based on the mass of nitrogen contained in the nitrogen source, is 500: 1-5: 1.

39. 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.

40. 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: 1-10: 1; preferably 2000: 1-20: 1.

41. the preparation method of any one of the platinum-carbon catalysts is characterized in that in the step (1), the boron source is one or more of boric acid and borate.

42. The method for producing a platinum-carbon catalyst according to any one of the preceding claims, characterized in that in (1), the mass ratio of the carbon material to the boron source is 10000: 1-10: 1; preferably 2000: 1-20: 1.

43. the preparation method of any one of the platinum-carbon catalysts is characterized in that the temperature is 450-700 ℃ in the operation of doping phosphorus and boron.

44. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, characterized in that the temperature is 550 ℃ to 900 ℃ in the sulfur and nitrogen doping operation.

45. The preparation method of any one of the platinum-carbon catalysts is characterized in that the treatment time in the phosphorus-boron doping operation and the sulfur-nitrogen doping operation is 1-5 h, preferably 2-4 h.

46. The preparation method of any one of the platinum-carbon catalysts described above, characterized in that in (1), the carbon material is graphene, carbon nanotubes or conductive carbon black; the conductive carbon Black is preferably EC-300J, EC-600JD, ECP-600JD, VXC72, Black pearls 2000, PRINTEX XE2-B, PRINTEX L6 or HIBLAXK 40B 2.

47. 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.

48. 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.

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

50. The method for preparing a platinum-carbon catalyst according to any one of the preceding claims, wherein the step (2) of supporting platinum comprises:

(a) dispersing the carbon carrier and the platinum precursor obtained in the step (1) 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.

51. 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.

52. 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.

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

54. 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 hetero atoms and the carbon material have various combination modes and various interactions, and the combination modes of the hetero atoms and the carbon material and the interactions between the hetero atoms can be influenced by different preparation methods and raw materials and different operation steps and conditions in the doping process, so that the properties of the hetero atoms and the carbon material are different, and the functions of the hetero atoms and the carbon material are changed. In the art, how to control the bonding mode of the heteroatom and the carbon material and the interaction between the heteroatoms is a difficulty in doping atoms. Controlling the manner in which the heteroatoms are bound to the carbon material and the interactions between the heteroatoms makes it possible to produce carbon materials with unique properties that make them suitable for particular applications. The research of the invention finds that the carbon corrosion resistance of the platinum-carbon catalyst can be improved more favorably when the carbon carrier is subjected to multi-element co-doping. The carbon material with uniform doping element combination mode can be prepared by carrying out sulfur nitrogen phosphorus boron four doping on the carbon material by a relatively simple method, and XPS analysis spectrum of the carbon material shows that sulfur doped on the surface of the carbon material exists in the form of thiophene type sulfur, nitrogen doped on the surface mainly exists in the form of pyrrole type nitrogen, boron doped on the surface has a characteristic peak only between 189ev and 191ev, and phosphorus doped on the surface has a characteristic peak only between 133.5ev and 135.5 ev. The inventor researches and finds that the characteristics are beneficial to improving the performance of the platinum-carbon catalyst of the hydrogen fuel cell, and particularly beneficial to improving the performance of the platinum-carrying platinum-carbon catalyst.

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

Compared with the existing doped carbon material, the carbon material has the advantages that the sulfur doped on the surface exists only in the form of thiophene type sulfur, the nitrogen doped on the surface mainly exists in the form of pyrrole type nitrogen, the boron doped on the surface has a characteristic peak only between 189ev and 191ev, and the phosphorus doped on the surface has a characteristic peak only between 133.5ev and 135.5ev, and the characteristics are found to be beneficial to improving the catalytic performance of the platinum-carbon catalyst of the fuel cell.

The carbon material is suitable for manufacturing a platinum-carbon catalyst with high platinum loading, and still has excellent comprehensive catalytic performance and carbon corrosion resistance when the platinum loading is up to 70 wt%.

And thirdly, 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 chemical reduction method has simple process, but the utilization rate of platinum is low and the catalytic activity is lower. However, a high platinum-carrying amount catalyst having excellent specific activity and stability can be easily produced by an aqueous chemical reduction method using the carbon material produced by the present invention as a carrier.

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 sulfur for a S-N-P-B doped carbon material of example 1.

FIG. 2 is an XPS spectrum of nitrogen for a S-N-P-B doped carbon material of example 1.

FIG. 3 is an XPS spectrum of the phosphorus of the S-N-P-B doped carbon material of example 1.

FIG. 4 is an XPS spectrum of boron from a S-N-P-B doped carbon material of example 1.

FIG. 5 is an XPS spectrum of sulfur for S-N-P-B doped carbon material of example 2.

FIG. 6 is an XPS spectrum of nitrogen for a S-N-P-B doped carbon material of example 2.

FIG. 7 is an XPS spectrum of phosphorus for a S-N-P-B doped carbon material of example 2.

FIG. 8 is an XPS spectrum of boron from a S-N-P-B doped carbon material of example 2.

Fig. 9 is an XPS spectrum of sulfur for the platinum carbon catalyst of example 3.

Figure 10 is an XPS spectrum of nitrogen for the platinum carbon catalyst of example 3.

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

Figure 12 is an XPS spectrum of nitrogen for the platinum carbon catalyst of example 5.

Fig. 13 is a TEM image of the platinum-carbon catalyst of example 5.

FIG. 14 is an XPS spectrum of phosphorus for the phosphorus-doped carbon material of comparative example 4.

Fig. 15 is an XPS spectrum of boron of the boron-doped carbon material of comparative example 5.

Fig. 16 is an XPS spectrum of sulfur of the sulfur-doped carbon material of comparative example 6.

Fig. 17 is an XPS spectrum of nitrogen for the nitrogen-doped carbon material of comparative example 7.

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 defined according to their definitions and are understood according to their ordinary meanings in the art without definitions.

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

The numerical ranges defined in this disclosure include the endpoints of the numerical ranges.

In the present invention, unless it is uniquely identified as "carbon material containing a doping element" according to the context or self-limitation, the other references to "carbon material" refer to 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 boron-sulfur-nitrogen-phosphorus-doped carbon material in the preparation method 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 nitrogen phosphorus boron doped carbon material, S analyzed by XPS_2PAmong the peaks, there is only a characteristic peak of thiophene-type sulfur between 160eV and 170 eV.

According to the sulfur nitrogen phosphorus boron doped carbon material, sulfur, nitrogen, phosphorus and boron are combined with the carbon material in a chemical bond mode.

The sulfur nitrogen phosphorus boron doped carbon material does not contain other doping elements except sulfur, nitrogen, phosphorus and boron.

The sulfur nitrogen phosphorus boron doped carbon material does not contain metal elements.

According to the sulfur nitrogen phosphorus boron doped carbon material, the characteristic peak of the thiophene type sulfur is between 162ev and 166 ev.

According to the sulfur nitrogen phosphorus boron doped carbon material, the characteristic peaks of the thiophene sulfur are double peaks and are respectively located at 163.4 +/-0.5 ev and 164.6 +/-0.5 ev.

N in XPS analysis of a sulfur nitrogen phosphorus boron doped carbon material according to the invention_1sAmong the peaks, the peak area between 399eV and 400.5eV is 70% or more, preferably 80% or more, more preferably 90% or more of the total area of the peak between 390eV and 410 eV.

The S-N-P-B doped carbon material according to the present invention, in some examples, has N analyzed by XPS_1sIn the spectrum peaks, the characteristic peak area between 399eV and 400.5eV accounts for 90 to 99 percent of the total area of the characteristic peaks between 390eV and 410 eV.

N in XPS analysis of a sulfur nitrogen phosphorus boron doped carbon material according to the invention_1sAmong the spectral peaks, there are two characteristic peaks between 399ev and 400.5ev, one characteristic peak at 401.5ev +/-0.5 ev, and no other characteristic peaks between 390ev and 410 ev.

Sulfur according to the inventionNitrogen phosphorus boron doped carbon material, P analyzed in XPS thereof_2PAmong the spectral peaks, there are two characteristic peaks between 133ev and 135ev, and there are no other characteristic peaks between 125ev and 145 ev.

B-S-N-P-B doped carbon material in XPS analysis thereof according to the present invention_1sAmong the spectral peaks, there are two characteristic peaks between 189ev and 191.5ev, and there are no other characteristic peaks between 185ev and 200 ev.

B-S-N-P-B doped carbon material in XPS analysis thereof according to the present invention_1sAmong the peaks, there is a characteristic peak at 189.6 eV. + -. 0.5 eV.

According to the sulfur nitrogen phosphorus boron doped carbon material, in XPS analysis, the mass fraction of sulfur is 0.01-6%, the mass fraction of nitrogen is 0.01-6%, the mass fraction of phosphorus is 0.01-6%, and the mass fraction of boron is 0.01-6%; preferably, the mass fraction of sulfur is 0.1-2%, preferably the mass fraction of nitrogen is 0.1-4%, preferably the mass fraction of phosphorus is 0.1-4%, preferably the mass fraction of boron is 0.1-4%.

In some embodiments of the carbon material doped with S, N, P, and B according to the present invention, the sulfur content is 0.1-1.5 wt%, the nitrogen content is 0.1-3.5 wt%, the phosphorus content is 0.01-2.5 wt%, and the boron content is 0.1-2.5 wt% in XPS analysis

The carbon material doped with boron phosphorothioate according to the present invention has a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <3 Ω · m.

The sulfur nitrogen phosphorus boron doped carbon material according to the present invention is not particularly limited in its oxygen content. Generally, the XPS analysis of the oxygen content of the compound is 2 to 15 percent.

The specific surface area and pore volume of the S, N, P, B doped carbon material 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 nitrogen phosphorus boron doped carbon material, the sulfur nitrogen phosphorus boron doped carbon material can be sulfur nitrogen phosphorus boron doped graphene, sulfur nitrogen phosphorus boron doped carbon nano tube or sulfur nitrogen phosphorus boron doped conductive carbon black. The Conductive carbon black can be common Conductive carbon black (Conductive black), Super Conductive carbon black (Super Conductive black) or special Conductive carbon black (Extra Conductive black), 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 et Ltd; 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 nitrogen phosphorus boron 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 nitrogen phosphorus boron doped carbon material, the carbon nano tube or the graphene can be the carbon nano tube or the graphene subjected to oxidation treatment, and can also be the carbon nano tube or the graphene not subjected to oxidation treatment.

The invention also provides a doping method of the carbon material, which comprises the following steps: (1) the carbon material is firstly contacted with a phosphorus source and a boron source, and is treated (preferably constant temperature treatment) for 0.5 to 10 hours at 300 to 800 ℃ in inert gas to obtain a phosphorus-boron doped carbon material (intermediate product); (2) then contacting with a sulfur source and a nitrogen source, and treating for 0.5-10 h at 400-1000 ℃ in inert gas to obtain the sulfur nitrogen phosphorus boron doped carbon material.

According to the doping method of the carbon material of the present invention, the carbon material may be graphene, carbon nanotubes, or conductive carbon black. 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 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 doping method of the carbon material, the carbon nanotube or the graphene can be the carbon nanotube or the graphene which is subjected to oxidation treatment, or the carbon nanotube or the graphene which is not subjected to oxidation treatment.

The method for doping the carbon material according to the present invention is not limited to the method for producing the conductive carbon black and the source thereof. The conductive carbon black may be acetylene black, furnace black, or the like.

According to the doping method of the carbon material, I of the carbon material_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 method for doping a carbon material of the present invention, the carbon material is preferably contacted with a phosphorus source and a boron source in a mixed manner. The present invention is not limited to the order and manner of mixing the carbon material with the phosphorus source and the boron source, and one skilled in the art can select an appropriate order and manner based on the teachings and/or prior knowledge of the present invention. The present invention provides a preferred mixing method: the carbon material is mixed with a phosphorus source and a boron source solution (preferably an aqueous solution), impregnated and dried.

According to the method for doping a carbon material of the present invention, the phosphorus boron doped carbon material (intermediate product) is preferably contacted with the sulfur source and the nitrogen source in a mixed manner. The present invention is not limited to the order and manner of mixing the intermediate product with the sulfur and nitrogen sources, and those skilled in the art can select an appropriate order and manner based on the teachings and/or prior knowledge of the present invention. The present invention provides a preferred mixing method: the intermediate product is first mixed with a nitrogen source solution, preferably an aqueous solution, impregnated and then dried, and then mixed with a sulfur source, such as elemental sulfur.

According to the doping method of the carbon material, the temperature is raised as required in any operation process, the temperature raising rate can be 1-20 ℃/min, and the preferable temperature raising rate is 3-15 ℃/min; more preferably, the mixing rate is 3-7 deg.C/min when doping boron and phosphorus, and 5-10 deg.C/min when doping nitrogen and sulfur.

According to the doping method of the carbon material of the present invention, (1) and (2), the treatment time is 1 to 5 hours, preferably 2 to 4 hours, independently of each other.

According to the method for doping a carbon material of the present invention, in (1), the temperature is 450 to 700 ℃.

According to the method for doping a carbon material of the present invention, in (2), the temperature is 550 to 900 ℃.

According to the doping method of the carbon material, the sulfur source is elemental sulfur.

According to the doping method of the carbon material, 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 doping method of the carbon material of the present invention, the nitrogen source is ammonia water or urea.

According to the doping method of the carbon material, the mass ratio of the carbon material to the nitrogen source is 500: 1-5: 1, preferably 200: 1-10: 1.

according to the doping method of the carbon material, the phosphorus source is one or more of phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogen phosphate, dihydrogen phosphate, phosphite and hypophosphite.

According to the doping method of the carbon material, 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: 1-10: 1; preferably 2000: 1-20: 1.

according to the doping method of the carbon material of the present invention, the boron source is one or more of boric acid and borate.

According to the doping method of the carbon material, the mass of the boron source is calculated by the mass of boron contained in the boron source, and the mass ratio of the carbon material to the boron source is 10000: 1-10: 1; preferably 2000: 1-20: 1.

according to the doping method of the carbon material of the present invention, the inert gas is nitrogen or argon.

According to the doping method of the carbon material, the carbon material has an oxygen mass fraction of generally more than 4%, preferably 4% to 15% in XPS analysis.

According to the method for doping a carbon material of the present invention, the carbon material has a resistivity of <10 Ω · m, preferably <5 Ω · m, more preferably <2 Ω · m.

According to the method for doping a carbon material of the present invention, the specific surface area of the carbon material may vary over a wide 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 method for doping a carbon material of the present invention, in one embodiment, (1) the carbon material impregnated with a phosphorus source and a boron source in an aqueous solution is dried, placed in a tube furnace, and the tube furnace is heated to 300 ℃ to 800 ℃ (preferably 450 ℃ to 700 ℃) at a rate of 3 ℃/min to 7 ℃/min in an inert gas, and then subjected to constant temperature treatment for 0.5h to 10h to obtain a phosphorus-boron doped carbon material (intermediate product); (2) drying the intermediate product which is soaked in the water solution with the nitrogen source, then uniformly mixing the dried intermediate product with sulfur powder, then placing the mixture in a tubular furnace, heating the tubular furnace to 400-1000 ℃ (preferably 550-900 ℃) at the speed of 5-10 ℃/min in inert gas, and then carrying out constant temperature treatment for 0.5-10 h to obtain the sulfur nitrogen phosphorus boron doped carbon material.

The inert gas is nitrogen or argon.

According to the doping method of the carbon material of the present invention, a metal-containing catalyst is not used in the doping of the carbon material.

The invention also provides a sulfur nitrogen phosphorus boron doped carbon material prepared by any one of the methods.

Any one of the above-described carbon materials doped with sulfur, nitrogen, phosphorus and boron of the present invention is used as an electrode material in electrochemistry.

The invention provides a platinum-carbon catalyst, which comprises a carbon carrier and platinum metal loaded on the carbon carrier, wherein the carbon carrier is a sulfur-nitrogen-phosphorus-boron doped carbon material, and S analyzed by XPS of the platinum-carbon catalyst_2PAmong the peaks, there is only a characteristic peak of thiophene-type sulfur between 160eV and 170 eV.

According to the platinum-carbon catalyst, the characteristic peak of the thiophene sulfur is between 162ev and 166 ev.

According to the platinum-carbon catalyst, the characteristic peaks of the thiophene sulfur are double peaks and are respectively located at 163.4 +/-0.5 ev and 164.6 +/-0.5 ev.

Platinum-carbon catalyst according to the invention, N in its XPS analysis_1sAmong the spectral peaks, there were characteristic peaks between 399ev and 400.5ev, and there were no other characteristic peaks between 390ev and 410 ev.

The platinum-carbon catalyst according to the present invention, in some embodiments, N analyzed by XPS thereof_1sAmong the spectral peaks, there are two characteristic peaks between 399ev and 400.5ev, and there are no other characteristic peaks between 390ev and 410 ev.

The platinum-carbon catalyst according to the present invention has no B between 185ev and 200ev in its XPS analysis_1sAnd no P between 125ev and 145ev_2pCharacteristic peak of (2).

The platinum-carbon catalyst according to the invention detected P, P in the TG-MS (thermogravimetric-mass spectrometry) test₂O₃And P₂O₅Of the signal of (1).

According to the platinum-carbon catalyst of the present invention, boron signals (B and B) were detected in TG-MS (thermogravimetric-mass spectrometry) test₂O₃)。

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

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, nitrogen, phosphorus and boron are chemically bonded to a carbon material.

According to the platinum-carbon catalyst of the present invention, the carbon support is any one of the above-described sulfur, nitrogen, phosphorus and boron doped carbon materials of the present invention.

According to the platinum-carbon catalyst of the present invention, the carbon material may be graphene, carbon nanotubes, or conductive carbon black. 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 Wingchuang Texaco 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.

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。

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

(1) a step of manufacturing a carbon support: firstly, contacting a carbon material with a phosphorus source and a boron source, and treating (preferably, treating at constant temperature) for 0.5-10 h at 300-800 ℃ in an inert gas; then contacting with a sulfur source and a nitrogen source, and treating (preferably treating at constant temperature) for 0.5-10 h at 400-1000 ℃ in inert gas to obtain the carbon carrier;

(2) a step of supporting platinum with the carbon carrier obtained in (1).

According to the preparation method of the platinum-carbon catalyst of the present invention, (1), "the contact manner of the carbon material with the sulfur source, the nitrogen source, the phosphorus source and the boron source" is the same as that of the corresponding parts in the foregoing, and the details are not repeated herein.

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 (1), 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; preferably, the ratio of 8: 1-4: 1.

according to the preparation method of the platinum-carbon catalyst, the nitrogen source is ammonia water or urea.

According to the preparation method of the platinum-carbon catalyst, in the step (1), the mass ratio of the carbon material to the nitrogen source is 500: 1-5: 1, preferably 200: 1-10: 1.

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: 1-10: 1; preferably 2000: 1-20: 1.

according to the preparation method of the platinum-carbon catalyst, the boron source is one or more of boric acid and borate.

According to the preparation method of the platinum-carbon catalyst of the invention, (1) the mass of the boron source is calculated by the mass of boron contained therein, and the mass ratio of the carbon material to the boron source is 10000: 1-10: 1; preferably 2000: 1-20: 1.

according to the preparation method of the platinum-carbon catalyst, the temperature is raised as required in the step (1), wherein the temperature rise rate can be 1-20 ℃/min, and is preferably 3-15 ℃/min; more preferably, the mixing rate is 3-7 deg.C/min when doping boron and phosphorus, and 5-10 deg.C/min when doping nitrogen and sulfur.

According to the preparation method of the platinum-carbon catalyst, in the operation of doping phosphorus and boron in the step (1), the temperature is 450-700 ℃.

According to the preparation method of the platinum-carbon catalyst, in the operation of doping sulfur and nitrogen in the step (1), the temperature is 550-900 DEG C

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

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

According to the preparation method of the platinum-carbon catalyst of the invention, (1), the carbon material can be graphene, carbon nanotubes or conductive carbon black; the conductive carbon Black is 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 platinum-carbon catalyst, the carbon material doped with sulfur, nitrogen, phosphorus and boron prepared in the step (1) can be easily dispersed in a water phase. However, it is difficult to disperse the carbon material such as ketjen black directly in the aqueous phase.

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.

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

A hydrogen fuel cell comprising an anode and/or a cathode, wherein any one of the platinum-carbon catalysts described above is used.

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 an ESCALB 220i-XL type ray photoelectron spectrum analyzer which is manufactured by VG scientific company and is provided with Avantage V5.926 software, and the X-ray photoelectron spectrum 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 peaks of thiophene-type sulfur, nitrogen, phosphorus and boron in the spectrogram are the characteristic peaks 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 1.0V to 1.5V, 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 method: 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 258m²(g), pore volume 0.388mL/g, oxygen mass fraction 8.72% by XPS analysis, I_D/I_G1.02, and a resistivity of 1.22. omega. m.

Ketjenblack ECP600JD (Ketjen Black, produced by Lion, Japan) was purchased from Suzhou wingong sandisk energy science and technology Co., Ltd. The results of the tests by the instrument method show that: specific surface area 1362m²Volume of pores/g, 2.29mL/g, XPS analysis oxygen mass fraction of 6.9%, I_D/I_G1.25, and resistivity of 1.31. omega. m.

Black Pearls 2000 (produced by Kabott, USA) is purchased from Suzhou wingong sandisk energy science and technology, Inc. The results of the tests by the instrument method show that: specific surface area 1479m²(g), XPS analysis oxygen mass fraction 9.13%; I_D/I_G1.14, and resistivity of 1.19. 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 the preparation of a carbon material doped with sulfur, nitrogen, phosphorus and boron in accordance with the present invention.

Dipping 1g of Vulcan XC72 in 15mL of aqueous solution with 0.5 wt% of sodium borate and 2.5 wt% of phosphoric acid for 16 h; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 450 ℃ at the speed of 5 ℃/min, and carrying out constant temperature treatment for 2 h; and naturally cooling to obtain the phosphorus-boron doped carbon material.

Dipping the phosphorus-boron doped carbon material in 20mL of ammonia water solution with the ammonia concentration of 1.2 wt% for 24 h; drying in an oven at 100 ℃; then evenly mixing the sulfur with 0.167g of elemental sulfur, putting the mixture into a tubular furnace, heating the tubular furnace to 900 ℃ at the speed of 8 ℃/min, and carrying out constant temperature treatment for 3 h; and naturally cooling to obtain the sulfur nitrogen phosphorus boron doped carbon material which is numbered as a carbon carrier A.

Sample characterization and testing

The sulfur mass fraction by XPS analysis was 0.6%; the nitrogen mass fraction by XPS analysis was 2.7%; the mass fraction of phosphorus analyzed by XPS was 1.9%; the boron mass fraction of XPS analysis is 1.8%; the specific surface area is 236m²(ii)/g; resistivity of 1.32. omega. m.

In FIG. 2, the ratio of the sum of characteristic peak areas between 399eV and 400.5eV to the other characteristic peak areas between 390eV and 410eV is 10.8.

Example 2

Adding 10mL of absolute ethanol into 1g of Ketjenblack ECP600JD, and then adding 25mL of aqueous solution with boric acid concentration of 0.8 wt% and sodium dihydrogen phosphate concentration of 0.4 wt% for impregnation for 20 h; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 700 ℃ at the speed of 5 ℃/min, and carrying out constant temperature treatment for 2 h; and naturally cooling to obtain the boron-phosphorus doped carbon material.

Adding the boron-phosphorus doped carbon material into 35mL of aqueous solution with urea concentration of 0.1 wt% for soaking for 20h, and drying in an oven at 100 ℃; then evenly mixing the mixture with 0.25g of elemental sulfur and nitrogen, putting the mixture into a tubular furnace, heating the tubular furnace to 550 ℃ at the speed of 6 ℃/min, and carrying out constant temperature treatment for 3 h; and naturally cooling to obtain the sulfur nitrogen boron phosphorus doped carbon material numbered as a carbon carrier B.

Sample characterization and testing

The sulfur mass fraction by XPS analysis was 0.9%; the nitrogen mass fraction by XPS analysis was 1.7%(ii) a The mass fraction of phosphorus analyzed by XPS is 0.4%; the boron mass fraction of XPS analysis is 2.1%; the specific surface area is 1341m²(ii)/g; resistivity was 1.39. omega. m.

In FIG. 6, the ratio of the sum of characteristic peak areas between 399eV and 400.5eV to the other characteristic peak areas between 390eV and 410eV is 13.7.

Example 3

This example illustrates the preparation of a platinum carbon catalyst according to the 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 39.7%.

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

P, P detected in TG-MS test of platinum-carbon catalyst₂O₃And P₂O₅Of the signal of (1).

In XPS analysis of platinum-carbon catalystsNo B between 185ev and 200ev_1sCharacteristic peak of (2).

Detection of B and B in TG-MS test of platinum-carbon catalyst₂O₃Of the signal of (1).

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

Example 4

This example illustrates the preparation of a platinum carbon catalyst.

A platinum carbon catalyst was prepared according to the method of example 3, except that: per gram of carbon support 1.3mmol of chloroplatinic acid was added.

Sample characterization and testing

The platinum mass fraction of the platinum-carbon catalyst was 20.3%.

Example 5

Dispersing a carbon carrier B into a solution according to the proportion of using 600mL of water and 600mL of glycol per gram of carbon carrier, adding 12mmol of chloroplatinic acid per gram of carbon carrier, adding sodium acetate according to the molar ratio of the sodium acetate to the chloroplatinic acid of 2:1, 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 sodium borohydride into the suspension under stirring to perform reduction reaction, wherein the molar ratio of the sodium borohydride to the chloroplatinic acid is 5:1, 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 70.2%.

Fig. 13 is a TEM image of the platinum-carbon catalyst of example 5.

No B was found in XPS analysis of the platinum-carbon catalyst at 185 to 200eV_1sCharacteristic peak of (2).

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%.

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

Comparative example 2

According to the proportion of using 600mL of water and 600mL of ethylene glycol per gram of carbon carrier, dispersing Ketjenblack ECP600JD in a solution, adding 12mmol of chloroplatinic acid per gram of carbon carrier, adding sodium acetate according to the molar ratio of the sodium acetate to the chloroplatinic acid of 2:1, performing ultrasonic dispersion to form a 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 sodium borohydride into the suspension under stirring to perform reduction reaction, wherein the molar ratio of the sodium borohydride to the chloroplatinic acid is 5:1, 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 69.9%.

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%.

The results of the platinum carbon catalyst performance test are shown in Table 1.

Comparative example 4

This comparative example serves to illustrate the preparation of a phosphorus doped carbon material.

1g of Vulcan XC72 was immersed in 15mL of a 0.8 wt% aqueous phosphoric acid solution for 16 h; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 400 ℃ at the speed of 8 ℃/min, and carrying out constant temperature treatment for 2 h; and naturally cooling to obtain the phosphorus-doped carbon material.

Sample characterization and testing

Comparative example 5

This comparative example serves to illustrate the preparation of a boron doped carbon material.

1g of Vulcan XC72 was immersed for 16h in 15mL of 4.5 wt% aqueous sodium borate solution; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 400 ℃ at the speed of 10 ℃/min, and carrying out constant temperature treatment for 3 h; and naturally cooling to obtain the boron-doped carbon material.

Sample characterization and testing

Comparative example 6

This comparative example serves to illustrate the preparation of a sulfur-doped carbon material.

Uniformly mixing 1g of Ketjenblack ECP600JD with 0.25g of elemental sulfur and nitrogen, putting the mixture into a tube furnace, heating the tube furnace to 500 ℃ at the speed of 5 ℃/min, and carrying out constant-temperature treatment for 3 h; and naturally cooling to obtain the sulfur-doped carbon material.

Sample characterization and testing

Comparative example 7

This comparative example is illustrative of the preparation of a nitrogen doped carbon material.

1g of Vulcan XC72 in 20mL of 2.5 wt% ammonia solution for 24 h; drying in an oven at 100 ℃; then placing the tube furnace into a tube furnace, heating the tube furnace to 1100 ℃ at the speed of 8 ℃/min, and carrying out constant temperature treatment for 3 h; and naturally cooling to obtain the nitrogen-doped carbon material.

Sample characterization and testing

TABLE 1

Claims

2. The boron-phosphorous-sulfur-doped carbon material as claimed in claim 1, wherein N is analyzed by XPS_1sAmong the spectral peaks, the characteristic peak area between 399eV and 400.5eV accounts for more than 70% of the total area of the characteristic peaks between 390eV and 410 eV.

3. The boron-phosphorous-sulfur-doped carbon material as claimed in claim 1, wherein B is analyzed by XPS_1sAmong the peaks, there is a characteristic peak between 189eV and 191.5 eV.

4. The boron-sulfur-nitrogen-phosphorus-doped carbon material according to claim 1, which is a boron-sulfur-nitrogen-phosphorus-doped graphene, a boron-sulfur-nitrogen-phosphorus-doped carbon nanotube or a boron-sulfur-nitrogen-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. The carbon material doped with sulfur, nitrogen, phosphorus and boron according to claim 1, wherein the mass fraction of sulfur, phosphorus and boron is 0.01 to 6%, 0.01 to 6% and 0.01 to 6% respectively, in XPS analysis.

7. A method of doping a carbon material comprising: (1) firstly, contacting a carbon material with a phosphorus source and a boron source, and treating for 0.5-10 h at 300-800 ℃ in an inert gas; (2) then contacting with a sulfur source and a nitrogen source, and treating for 0.5 h-10 h in inert gas at 400-1000 ℃.

8. The method for doping a carbon material as claimed in claim 7, wherein the sulfur source is elemental sulfur.

9. The method for doping a carbon material according to claim 7, wherein the mass ratio of the carbon material to the sulfur source is 20: 1-2: 1.

10. the method for doping a carbon material as claimed in claim 7, wherein the nitrogen source is ammonia and/or urea.

11. The method for doping a carbon material as claimed in claim 7, wherein the mass ratio of the carbon material to the nitrogen source is 500: 1-5: 1.

12. the method for doping a carbon material as claimed in claim 7, wherein the phosphorus source is one or more selected from phosphoric acid, phosphate, pyrophosphate, polyphosphate, hydrogenphosphate, dihydrogenphosphate, phosphite and hypophosphite.

13. The method for doping a carbon material according to claim 7, wherein the mass ratio of the carbon material to the phosphorus source is 10000: 1-10: 1.

14. the method for doping a carbon material as claimed in claim 7, wherein the boron source is one or more of boric acid and a borate.

15. The method for doping a carbon material according to claim 7, wherein the mass ratio of the carbon material to the boron source is 10000: 1-10: 1.

16. a sulfur nitrogen phosphorus boron doped carbon material characterized by being produced by the method of any one of claims 7 to 15.

17. Use of the carbon material doped with sulfur, nitrogen, phosphorus and boron as claimed in any one of claims 1 to 6 and 16 as an electrode material in electrochemistry.

18. The platinum-carbon catalyst comprises a carbon carrier and platinum metal loaded on the carbon carrier, and is characterized in that the carbon carrier is a sulfur-nitrogen-phosphorus-boron doped carbon material, and S analyzed by XPS (X-ray diffraction) of the platinum-carbon catalyst_2PAmong the peaks, there is only a characteristic peak of thiophene-type sulfur between 160eV and 170 eV.

19. Platinum-carbon catalyst according to claim 18, characterised in that the N analyzed in its XPS_1sIn the spectrum peaks, except that there are characteristic peaks between 399eV and 400.5eV, there are no other characteristic peaks between 390eV and 410 eV.

20. Platinum-carbon catalyst according to claim 18, characterized in that in its XPS analysis there is no B between 185 and 200eV_1sAnd no P between 125ev and 145ev_2pCharacteristic peak of (2).

21. A platinum-carbon catalyst according to claim 18, wherein the carbon support is the boron-phosphorous-sulfur doped carbon material according to any one of claims 1 to 6 and 16.

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

(1) a step of manufacturing a carbon support: firstly, contacting a carbon material with a phosphorus source and a boron source, and treating for 0.5-10 h at 300-800 ℃ in an inert gas; then contacting with a sulfur source and a nitrogen source, and treating for 0.5 h-10 h at 400-1000 ℃ in inert gas to obtain the carbon carrier;

(2) a step of supporting platinum with the carbon carrier obtained in (1).

23. The method for preparing a platinum-carbon catalyst according to claim 22, wherein the step (2) of supporting platinum comprises:

(a) dispersing the carbon carrier and the platinum precursor obtained in the step (1) in a water phase, and adjusting the pH to 8-12;

(b) adding a reducing agent for reduction;

24. The method for preparing a platinum-carbon catalyst according to claim 22, 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.

25. The method for preparing a platinum-carbon catalyst according to claim 22, 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.

26. A platinum carbon catalyst, characterised in that it is obtainable by a process according to any one of claims 22 to 25.

27. A hydrogen fuel cell, characterized in that a platinum-carbon catalyst according to any one of claims 18 to 21 and 26 is used in an anode and/or a cathode of the hydrogen fuel cell.