Preparation method of a nitrogen-doped carbon material

Abstract

The present invention discloses a method for preparing nitrogen-doped carbon materials, which belongs to the field of electrocatalysis technology. The present invention uses ion beam sputtering technology to perform nitrogen doping treatment on carbon materials to prepare nitrogen-doped carbon materials, which can be used as carriers to improve the catalytic performance of carbon-supported catalysts. The present invention first uses an auxiliary ion source to induce the diffusion of N + The beam assists in cleaning the surface of the carbon material. After cleaning, the screen pressure is adjusted to make the divergent N + The beam intensity is reduced and low-energy divergence N is used. + Beam bombards the carbon material surface, N + Nitrogen-doped carbon materials are obtained by elastically colliding with carbon atoms on the surface of carbon materials, thereby replacing carbon atoms. This material has the advantages of short preparation time, low preparation temperature, and high nitrogen content. When used as a support for carbon-supported Au-based catalysts, it can effectively improve the hydrogen evolution and hydrogenation performance of carbon-supported Au-based catalysts.

Description

Technical Field

[0001] The present invention belongs to the technical field of electrocatalysis, and in particular relates to a method for preparing a nitrogen-doped carbon material. Background Art

[0002] Carbon-supported metal catalysts are excellent catalysts. In order to improve their catalytic performance, in addition to changing the type and structure of the supported metal, modification of the carbon substrate is also an effective method to improve catalytic performance, such as doping non-metallic elements N, S, F, etc. into the carbon substrate, among which N doping is considered to be the best choice. Nitrogen-doped carbon materials refer to a new type of material in which nitrogen atoms are introduced into the carbon structure, replacing C atoms, forming bonds with surrounding C atoms or incorporating into the carbon skeleton. Nitrogen doping increases the conductivity of the carbon material, changes the local electronic structure of the carbon material, promotes the adsorption of reactants, and produces a good metal-support interaction with the supported metal. It is an effective method to improve the electrocatalytic performance of carbon-supported metal catalysts. At present, the preparation methods of nitrogen-doped carbon materials mainly include post-synthesis method and in-situ synthesis method. Although these two preparation methods have their own advantages, there are also some problems such as high preparation temperature, long preparation time, and low nitrogen content. Summary of the Invention

[0003] In order to solve the problems of high preparation temperature, long preparation time and low nitrogen content in nitrogen-doped carbon materials, the present invention provides a method for preparing nitrogen-doped carbon materials, using an auxiliary ion source to induce low-intensity divergent N + The nitrogen-doped carbon material prepared by beam bombarding the carbon material surface can form pyridinic nitrogen, graphitic nitrogen, and N-oxide species on the carbon material surface in a short time at a low temperature (210°C). The nitrogen content can reach 13.89at%. This can be used in the field of electrocatalysis to effectively enhance the catalytic performance of the material.

[0004] To achieve the above object, the present invention provides the following technical solutions:

[0005] A nitrogen-doped carbon material that uses an auxiliary ion source to induce low-intensity divergent N + The beam bombards the surface of the carbon material, making N + By replacing the C atoms on the surface of the carbon material, nitrogen-doped carbon material is obtained.

[0006] Furthermore, an auxiliary ion source is used to induce low-intensity divergent N + The beam current intensity is 40mA.

[0007] Furthermore, the carbon material is graphite fiber cloth or graphite sheet.

[0008] Furthermore, the divergence N + The beam bombardment time is 90-180s.

[0009] Furthermore, the nitrogen content in the nitrogen-doped carbon material is 6.02-13.89 at%. The nitrogen content on the surface of the nitrogen-doped carbon material can be determined based on the N + The beam bombardment time is adjusted. The nitrogen species include pyridinic nitrogen, graphitic nitrogen and N-oxide species.

[0010] The present invention also provides a method for preparing the nitrogen-doped carbon material, comprising the following steps:

[0011] 1) placing the carbon material in 0.5 mol / L sulfuric acid, acetone and deionized water in sequence for ultrasonic cleaning, and dehydrating and drying to obtain a pretreated carbon material;

[0012] 2) When the vacuum chamber pressure reaches 3.0×10 -2 Pa, the sample stage was heated to 210 °C and the vacuum chamber pressure reached 8.0 × 10 -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The beam is used to assist in cleaning the surface of the pretreated carbon material; after cleaning, the screen pressure is adjusted to make the divergent N + The beam intensity is reduced, and low-intensity N is used. + The beam bombards the carbon material to obtain nitrogen-doped carbon material.

[0013] Furthermore, the parameters during the auxiliary cleaning process are: cathode 16.2-16.5 A, anode 53-61 V, screen voltage 0.5 kV, beam current 50 mA, acceleration 200 V, and time 300 s.

[0014] Furthermore, the screen voltage was adjusted to 0.35 kV, and the anode and cathode parameters were adjusted to make the divergent N + The beam current intensity is 40mA.

[0015] Furthermore, the parameters during the bombardment process are: cathode 15.9-17A, anode 54-56V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and sputtering time 90-180s.

[0016] The present invention also provides an application of the nitrogen-doped carbon material as a Au-based catalyst carrier, wherein the Au-based catalyst is Au, Au-Ni, Au-Ti, Au-Ni-Ce or Au-Ti-Ce.

[0017] Furthermore, a sputtering ion source was used to extract Ar + The Au target was bombarded with a beam to prepare nitrogen-doped carbon-supported Au-based catalyst. The bombardment parameters were: cathode 14.3-14.5 A, anode 51-56 V, screen voltage 2 kV, beam current 70 mA, acceleration 140 V, and sputtering time 900 s.

[0018] Compared with the prior art, the present invention has the following advantages and technical effects:

[0019] 1. The present invention uses an ion beam sputtering device to prepare nitrogen-doped carbon materials. During sputtering, the vacuum chamber is in a high vacuum environment (8.0×10 -4 Pa), there is no intermediate pollutant, the prepared nitrogen-doped carbon material is highly pure, and the preparation process is simple.

[0020] 2. The present invention can control the divergence N + The beam bombardment time was adjusted to obtain nitrogen-doped carbon materials with different nitrogen contents.

[0021] 3. The nitrogen-doped carbon material prepared by the present invention can be used as a support. After preparation, it can be directly subjected to ion beam sputtering to prepare nitrogen-doped carbon-supported metal catalysts. This improves the electrical conductivity of the carbon material. The nitrogen species on the surface also provide anchor points for metal particles subsequently deposited on the surface of the nitrogen-doped carbon material, increasing atomic dispersion and fostering favorable metal-support interactions with the deposited metal, thereby enhancing catalytic performance. Furthermore, the nitrogen species can alter the local electronic structure of the carbon material, facilitating electron transfer and promoting the adsorption of reactants.

[0022] 4. The preparation time of the present invention is short and the preparation temperature is low, and the nitrogen content on the surface of the prepared nitrogen-doped carbon material can reach up to 13.89at%. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0024] Figure 1 The full XPS spectra in the range of 0-1400 eV of Comparative Example 1 and Example 1 are shown;

[0025] Figure 2 The XPS spectra of element C in Comparative Example 1 and Example 1 are shown;

[0026] Figure 3 The XPS spectra of the N element in Comparative Example 1 and Example 1 are shown;

[0027] Figure 4 1 is a comparison diagram of hydrogen evolution cyclic voltammetry curves (hydrogen evolution CV curves) of Comparative Example 2, Example 3, Example 5, and Example 6;

[0028] Figure 5 1 is a comparison diagram of polarization curves (LSV curves) of Comparative Example 2, Example 3, Example 5, and Example 6;

[0029] Figure 61 is a comparison diagram of hydrogenation cyclic voltammetry curves (hydrogenation CV curves) of Comparative Example 3, Example 7, Comparative Example 4, and Example 8;

[0030] Figure 7 It is a comparison diagram of the Tafel curves of Comparative Example 3, Example 7, Comparative Example 4 and Example 8. DETAILED DESCRIPTION

[0031] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0032] It should be understood that the terms described herein are intended only to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges herein, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between any intermediate value within a stated value or stated range and any other stated value or intermediate value within the stated range is also encompassed by the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.

[0033] Unless otherwise indicated, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the art. Although only preferred methods and materials are described herein, any methods and materials similar or equivalent to those described herein may also be used in the practice or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of any conflict with any incorporated document, the contents of this specification shall prevail.

[0034] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention without departing from the scope or spirit of the invention. Other embodiments will be apparent to those skilled in the art from the present invention. The present description and examples are intended to be illustrative only.

[0035] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0036] The raw materials used in the following examples of the present invention are all commercially available.

[0037] The present invention provides a nitrogen-doped carbon material, which uses an auxiliary ion source to induce low-intensity divergent N + The beam bombards the surface of the carbon material, making N + By replacing the C atoms on the surface of the carbon material and constructing nitrogen species on the surface of the carbon material, nitrogen-doped carbon material is obtained.

[0038] In some preferred embodiments, an auxiliary ion source is used to extract low-intensity divergent N + The beam current intensity is 40mA.

[0039] In some preferred embodiments, the carbon material is graphite fiber cloth or graphite sheet. The graphite fiber cloth is a plain weave acrylic graphite fiber cloth with an area density of 0.311 g cm -2 , graphite flakes are high-purity graphite flakes with a purity of ≥99.90%.

[0040] In some preferred embodiments, the bombardment time is 90-180 s.

[0041] In some preferred embodiments, the nitrogen content in the nitrogen-doped carbon material is 6.02-13.89 at%. The nitrogen content on the surface of the nitrogen-doped carbon material can be determined based on the N divergence. + The beam bombardment time is adjusted. The nitrogen species include pyridinic nitrogen, graphitic nitrogen and N-oxide species.

[0042] The present invention also provides a method for preparing the nitrogen-doped carbon material, comprising the following steps:

[0043] 1) Use an ultrasonic cleaning machine to clean the surface of the carbon material. In some preferred embodiments, prepare three beakers and add 0.5 mol / L H2SO4, acetone and deionized water respectively. Place the carbon material in a beaker filled with 0.5 mol / L H2SO4 and ultrasonically clean it for 12 minutes to remove metal pollutants on the surface of the carbon material; then continue to place the carbon material in a beaker filled with acetone and ultrasonically clean it for 12 minutes to remove organic pollutants on the surface of the carbon material; after cleaning, place it in a beaker filled with deionized water and ultrasonically clean it for 6 minutes to remove the H2SO4 and acetone remaining on the carbon material in the first two steps of cleaning, and finally immerse it in a tray filled with anhydrous ethanol for dehydration (6 minutes). After dehydration, move it into a digital display blower drying oven at 45°C for 40 minutes of drying. In addition, after each step in the cleaning process is completed, it is necessary to rinse with deionized water to remove pollutants attached to the surface of the carbon material when it leaves the cleaning liquid, and finally obtain a pretreated carbon material;

[0044] 2) The carbon material processed in step 1) was placed on the sample stage of the ion beam sputtering device, and the vacuum chamber pressure reached 3.0×10 -2 Pa, the sample stage was heated to 210 °C and the vacuum chamber pressure reached 8.0 × 10 -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The beam is used to assist in cleaning the surface of the carbon material; after cleaning, the screen pressure is reduced and the anode and cathode are adjusted so that the divergent N+ The beam intensity is reduced, and low-intensity N is used. + The beam bombards the carbon material, causing N + By elastically colliding with the C atoms on the surface of the carbon material and replacing the C atoms, nitrogen-doped carbon materials can be obtained.

[0045] In some preferred embodiments, the parameters during the auxiliary cleaning process are: cathode 16.2-16.5 A, anode 53-61 V, screen voltage 0.5 kV, beam current 50 mA, acceleration 200 V, and time 300 s.

[0046] In some preferred embodiments, the screen voltage is adjusted to 0.35 kV, and the anode and cathode parameters are adjusted to make the divergent N + The beam current intensity is 40mA.

[0047] In some preferred embodiments, the parameters during the bombardment process are: cathode 15.9-17A, anode 54-56V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and sputtering time 90-180s.

[0048] The present invention also provides an application of the nitrogen-doped carbon material as a Au-based catalyst carrier, wherein the Au-based catalyst is Au, Au-Ni, Au-Ti, Au-Ni-Ce or Au-Ti-Ce.

[0049] In some preferred embodiments, a sputtering ion source is used to extract Ar + The Au target was bombarded with a beam to prepare nitrogen-doped carbon-supported Au-based catalyst. The bombardment parameters were: cathode 14.3-14.5 A, anode 51-56 V, screen voltage 2 kV, beam current 70 mA, acceleration 140 V, and sputtering time 900 s.

[0050] The nitrogen-doped carbon material prepared by the present invention can be characterized using XPS to characterize its surface nitrogen species composition and surface nitrogen content. It can also serve as a support for Au-based catalysts, improving the hydrogen evolution and hydrogenation performance of carbon-supported Au-based catalysts. The hydrogen evolution performance of the carbon-supported Au-based catalysts was evaluated using cyclic voltammetry (CV) and linear polarization curves (LSV) using an electrochemical workstation and a three-electrode electrolytic cell. The hydrogen evolution peak area and exchange current density (i0) were obtained to evaluate the hydrogen evolution performance of the carbon-supported Au-based catalysts.

[0051] The three electrodes of the three-electrode electrolytic cell are a reference electrode (Ag / AgCl), a counter electrode (Pt sheet electrode), and a working electrode (the prepared carbon-supported Au-based catalyst or nitrogen-doped carbon-supported Au-based catalyst is cut into 3×4 cm pieces and clamped in a glassy carbon electrode fixture as the working electrode). The test liquid is 400 mL of a 0.5 mol / L H2SO4 solution, and the test temperature is 30°C. Before the test, the air inlet tube is inserted below the liquid surface and N2 is introduced to remove dissolved oxygen in the test liquid. After 15 minutes of ventilation, the air inlet tube is pulled above the liquid surface to ensure that the entire test process is protected by an N2 atmosphere to eliminate the influence of O2 on the test.

[0052] The test range of hydrogen evolution cyclic voltammetry curve is -0.3~1.65V (vsAg / AgCl), and the scan rate is 50mV s -1 The number of scanning cycles is 10, and the CV curve of the tenth cycle is taken to calculate the hydrogen evolution peak area of the sample (which directly reflects the number of surface active reaction sites).

[0053] LSV polarization curve, test range: -1.3~1.8V(vsAg / AgCl), scan rate: 10mV s -1 , take the data in the range of -0.4 to -0.28 V and calculate the exchange current density i0 according to formula (1). The magnitude of the exchange current density directly reflects the speed of the redox reaction on the sample surface. The larger the exchange current density i0, the faster the reaction.

[0054] lgA=KΔE+lgi0 (1)

[0055] in

[0056]

[0057] Where: K-constant; ΔE-overpotential; i0-exchange current density; F-Faraday constant; R-gas constant; T-electrode reaction temperature; Z-charge number; A-current.

[0058] During hydrogenation testing, the prepared carbon-supported Au-based catalyst or nitrogen-doped carbon-supported Au-based catalyst was first cut into 3×3 cm pieces and immersed in a mixture of 5% by mass Nafion solution, 5% by mass polytetrafluoroethylene (PTFE), and deionized water in a 1:1:1 volume ratio for 10 minutes. The sample was then removed and placed in a Petri dish. After air-drying, the sample was calcined in a muffle furnace at 600°C for 40 seconds. The treated carbon-supported Au-based catalyst or nitrogen-doped carbon-supported Au-based catalyst was then hot-pressed onto a Nafion membrane to form a SPE membrane electrode. Hydrogenation CV and Tafel tests were performed using a water electrolysis-hydrogenation apparatus. The hydrogenation peak area and exchange current density (j0) were obtained to evaluate the hydrogenation performance of the carbon-supported Au-based catalyst.

[0059] The water electrolysis-hydrogenation apparatus consists of a DC regulated power supply, an anode reaction chamber, and a cathode reaction chamber. During testing, the prepared SPE membrane electrode was placed between the anode and cathode reaction chambers, secured in series with bolts. 100 mL of a 0.5 mol / L H₂SO₄ solution was added to the anode reaction chamber, and the temperature was set to 30°C. 50 mL of a mixed solution (12 mL of cyclohexene and 38 mL of a mixture of glycerol and PEG600, mixed and shaken for 30 minutes) was added to the cathode reaction chamber, and the temperature was set to 50°C. The cathode and anode terminals of the DC regulated power supply were connected to the ports on either side of the anode chamber, respectively, with a voltage set to 1.6 V. An Ag / AgCl electrode was placed in the salt bridge, and the leads of the electrochemical workstation were connected to the Ag / AgCl electrode, the working electrode lead, and the Pt mesh electrode. Hydrogenation cyclic voltammetry (CV) and Tafel curves of the samples were measured.

[0060] The hydrogenation cyclic voltammetry curve test range is -3.0 ~ 0V (vsAg / AgCl) with a scan rate of 50mv s -1 The number of scanning circles is 5, and the hydrogenation CV curve of the fifth circle is taken to calculate the hydrogenation peak area of the sample (which directly reflects the number of surface active reaction sites).

[0061] The logarithm of the electrode current density is plotted against the overpotential to obtain a Tafel plot. The hydrogenation exchange current density (j0) is determined by extrapolating the intersection of the tangent lines on both sides of the Tafel plot.

[0062] The following examples serve as further illustrations of the technical solutions of the present invention.

[0063] Example 1

[0064] Step 1) Use an ultrasonic cleaning machine to clean the surface of the graphite sheet, prepare three beakers, and add 0.5 mol / L H2SO4, acetone and deionized water respectively. Place the graphite sheet in a beaker filled with 0.5 mol / L H2SO4 and ultrasonically clean it for 12 minutes to remove metal pollutants on the surface of the graphite sheet; then continue to place the graphite sheet in a beaker filled with acetone and ultrasonically clean it for 12 minutes to remove organic pollutants on the surface of the graphite sheet; after cleaning, place it in a beaker filled with deionized water and ultrasonically clean it for 6 minutes to remove the H2SO4 and acetone remaining on the graphite sheet in the first two steps of cleaning, and finally immerse it in a tray filled with anhydrous ethanol for dehydration (6 minutes). After dehydration, move it into a digital display blower drying oven at 45°C for 40 minutes of drying. In addition, after each step in the cleaning process is completed, it is necessary to rinse with deionized water to remove pollutants attached to the surface of the graphite sheet when it leaves the cleaning liquid, and finally obtain a pretreated graphite sheet;

[0065] Step 2) Place the graphite sheet processed in step 1) on the sample stage of the ion beam sputtering device, and place it on the sample stage of the ion beam sputtering device. -2 Pa, the sample stage was heated to 210 °C and the vacuum chamber pressure reached 8.0 × 10 -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The carbon material surface was cleaned with the beam for 300s. The cleaning parameters were: cathode 16.5A, anode 60V, screen voltage 0.5kV, beam current 50mA, acceleration 200V. After cleaning, the screen voltage was reduced to 0.35kV, and the anode and cathode were adjusted to make the divergent N + The beam current intensity is stable at 40mA, and the N + The graphite sheet was bombarded with a beam and nitrogen doping treatment was performed for 180s. The bombardment parameters were: cathode 17A, anode 55V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and nitrogen-doped graphite sheet was obtained.

[0066] An arbitrary piece of nitrogen-doped graphite sheet prepared in this example was taken for XPS testing.

[0067] Comparative Example 1

[0068] Step 1) is the same as step 1) of Example 1, obtaining a pretreated graphite sheet;

[0069] Step 2) is not performed.

[0070] Randomly select a pretreated graphite sheet for XPS testing.

[0071] Example 2

[0072] Step 1) is the same as step 1) in Example 1;

[0073] Step 2) is the same as step 2) in Example 1, except that the bombardment time is 90 seconds, that is, the nitrogen doping treatment is performed for 90 seconds.

[0074] XPS analysis was performed on a random piece of nitrogen-doped graphite prepared in this example to determine the surface nitrogen content and composition of the sample. The results showed that the surface nitrogen content of the nitrogen-doped graphite sheet was 6.02 at %, and the surface nitrogen species were pyridinic nitrogen, graphitic nitrogen, and N-oxide species.

[0075] Example 3

[0076] Step 1) is the same as step 1) of Example 1, except that the graphite sheet is replaced with graphite fiber cloth;

[0077] Step 2) is the same as step 2) in Example 1;

[0078] Step 3) The nitrogen-doped graphite fiber cloth prepared in step 2) is cut into a size of 3×4 cm, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0079] Comparative Example 2

[0080] Step 1) is the same as step 1) in Example 3;

[0081] Step 2) is not performed;

[0082] Step 3) Cut the graphite fiber cloth prepared in step 1) into a size of 3×4 cm, randomly select a sample, and perform hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0083] Results: The nitrogen-doped graphite fiber cloth prepared in Example 3 did not show a hydrogen evolution peak, and the exchange current density i0 was 0.405 mA cm -2 The graphite fiber cloth prepared in Comparative Example 2 did not show hydrogen evolution peak, and the exchange current density i0 was 0.307 mA cm -2 The exchange current density of Example 3 is increased by 31.92% compared with that of Comparative Example 2.

[0084] Example 4

[0085] Step 1) is the same as step 1) in Example 3;

[0086] Step 2) is the same as step 2) of Example 3, except that the bombardment time is 90 seconds, that is, the nitrogen doping treatment is performed for 90 seconds;

[0087] Step 3) The nitrogen-doped graphite fiber cloth prepared in step 2) is cut into a size of 3×4 cm, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0088] Results: The nitrogen-doped graphite fiber cloth prepared in Example 4 did not show a hydrogen evolution peak, and the exchange current density i0 was 0.359 mA cm -2 , the exchange current density is increased by 16.93% compared with that of comparative example 2.

[0089] Example 5

[0090] Step 1) is the same as step 1) in Example 3;

[0091] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au target on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The graphite fiber cloth surface was cleaned with a beam for 300s. The cleaning parameters were: cathode 16.3A, anode 59V, screen voltage 0.5kV, beam current 50mA, acceleration 200V. Then, a sputtering ion source was used to introduce high-energy Ar + The Au target was bombarded with a beam of 14.5A, anode 51V, screen voltage 2kV, beam current 70mA, acceleration 140V, and sputtering time 900s to prepare the Au / C catalyst.

[0092] Step 3) The Au / C catalyst prepared in step 2) is cut into 3×4 cm pieces, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0093] Results: The hydrogen evolution peak area of the Au / C catalyst prepared in Example 5 was 0.0148 mA·V, and the exchange current density i0 was 11.808 mA cm -2 .

[0094] Example 6

[0095] Step 1) is the same as step 1) in Example 5;

[0096] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au target on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N +The graphite fiber cloth surface was cleaned for 300s with the following cleaning parameters: cathode 16.5A, anode 61V, screen voltage 0.5kV, beam current 50mA, acceleration 200V; after cleaning, the screen voltage was reduced to 0.35kV, and the anode and cathode were adjusted to make the divergent N + The beam current intensity is stable at 40mA, using a divergent N with low beam current intensity. + The carbon material was bombarded with the beam and nitrogen doping was performed for 180 seconds. The parameters were: cathode 16.8A, anode 55V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and sputtering time 180s. Then the sputtering ion source was turned on to introduce high energy Ar + The Au target was bombarded with a beam to prepare the Au / NC catalyst. The bombardment parameters were: cathode 14.5A, anode 51V, screen voltage 2kV, beam current 70mA, acceleration 140V, and sputtering time 900s.

[0097] Step 3) The Au / NC catalyst prepared in step 2) is cut into a size of 3×4 cm, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0098] Results: The hydrogen evolution peak area of the Au / NC catalyst prepared in Example 6 was 0.473 mA·V, which was 3095.94% higher than that in Example 5; the exchange current density i0 was 27.951 mA cm -2 , an increase of 6801.48% compared with the third embodiment, and an increase of 136.71% compared with the fifth embodiment.

[0099] Comparative Example 3

[0100] Step 1) is the same as step 1) in Example 3;

[0101] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au and Ni targets on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The graphite fiber cloth surface was cleaned with the beam for 300s. Cleaning parameters: cathode 16.4A, anode 52V, screen voltage 0.5kV, beam current 50mA, acceleration 200V; after the auxiliary cleaning was completed, the sputtering ion source was turned on and Ar was introduced. + Au-Ni / C catalyst was prepared by beam co-sputtering of Au and Ni targets. Sputtering parameters were: cathode 14.4A, anode 53V, screen voltage 2kV, beam current 70mA, acceleration 140V, and sputtering time 900s.

[0102] Step 3) The Au-Ni / C catalyst prepared in step 2) was cut into 3×3 cm pieces and immersed in a mixture of 5% by mass Nafion solution, 5% by mass polytetrafluoroethylene (PTFE), and deionized water in a 1:1:1 volume ratio for 10 minutes. The sample was removed and placed in a Petri dish. After air drying, it was placed in a muffle furnace at 600°C for 40 seconds. The treated Au-Ni / C catalyst and Nafion membrane were hot-pressed to form a SPE-Au-Ni / C membrane electrode. Hydrogenation CV and Tafel tests were performed to obtain the hydrogenation peak area and exchange current density j0 of the sample.

[0103] Results: The hydrogenation peak area of the Au-Ni / C catalyst prepared in comparative example 3 was 0.396 mA·V; the exchange current density j0 was 1.697×10 -3 mA cm -2 .

[0104] Example 7

[0105] Step 1) is the same as step 1) in Example 3;

[0106] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au and Ni targets on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The graphite fiber cloth surface was cleaned with the beam for 300s. The cleaning parameters were: cathode 16.2A, anode 53V, screen voltage 0.5kV, beam current 50mA, acceleration 200V. After the auxiliary cleaning was completed, the screen voltage was reduced to 0.35kV, and the anode and cathode parameters were adjusted to make the divergent N + The beam current intensity is stable at 40mA, using a divergent N with low beam current intensity. + The carbon material was bombarded with the beam and nitrogen doping was performed for 180 seconds. The bombardment parameters were: cathode 16.2A, anode 56V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and sputtering time 180s. The sputtering ion source was then turned on to introduce high energy Ar + The Au-Ni / NC catalyst was prepared by bombarding the Au and Ni targets with a beam current of 14.3A cathode, 56V anode, 2kV screen voltage, 70mA beam current, 140V acceleration, and 900s sputtering time.

[0107] Step 3) is the same as step 3) of comparative example 3.

[0108] Results: The hydrogenation peak area of the Au-Ni / NC catalyst prepared in Example 7 was 0.682 mA·V, which was 72.22% higher than that in Comparative Example 3; the exchange current density j0 was 2.071×10 -3 mA cm -2 , an increase of 22.03% compared with comparative example three.

[0109] Comparative Example 4

[0110] Step 1) is the same as step 1) in Example 3;

[0111] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au, Ni and Ce targets on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The graphite fiber cloth was cleaned with the beam for 300s. The cleaning parameters were: cathode 16.2A, anode 54V, screen voltage 0.5kV, beam current 50mV, acceleration 200V. After the cleaning was completed, the sputtering ion source was turned on to introduce high-energy Ar + The Au-Ni-Ce / C catalyst was prepared by bombarding Au, Ni, and Ce targets with a beam current of 13.9A at the cathode, 56V at the anode, 2kV at the screen voltage, 70mA at the beam current, 140V at the acceleration, and 900s at the sputtering time.

[0112] Step 3) is the same as step 3) of comparative example 3.

[0113] Results: The hydrogenation peak area of the Au-Ni-Ce / C catalyst prepared in Comparative Example 4 was 0.309 mA·V; the exchange current density j0 was 2.179×10 -3 mA cm -2 .

[0114] Example 8

[0115] Step 1) is the same as step 1) in Example 3;

[0116] Step 2) Place the graphite fiber cloth obtained in step 1) on the sample stage of the ion beam sputtering device, place the sample stage in the vacuum chamber of the ion beam sputtering device, and install the Au, Ni and Ce targets on the target stage. -2 Pa, the sample stage was heated to 210°C. -4 Pa, the auxiliary ion source is turned on to induce the divergence of N +The graphite fiber cloth was cleaned with the beam for 300s. The cleaning parameters were: cathode 16.3A, anode 55V, screen voltage 0.5kV, beam current 50mA, acceleration 200V. After cleaning, the screen voltage was reduced to 0.35kV, and the anode and cathode were adjusted to make the divergent N + The beam current intensity is stable at 40mA, using a divergent N with low beam current intensity. + The carbon material was bombarded with the beam and nitrogen doping treatment was carried out for 180s. The bombardment parameters were: cathode 15.9A, anode 54V, screen voltage 0.35kV, beam current 40mA, acceleration 200V, and sputtering time 180s. Then the main sputtering source of the ion beam was turned on to introduce high energy Ar + The Au-Ni-Ce / NC catalyst was prepared by bombarding Au, Ni, and Ce targets with a beam current of 14.3A cathode, 52V anode, 2kV screen voltage, 70mA beam current, 140 acceleration, and 900s sputtering time.

[0117] Step 3) is the same as step 3) of comparative example 3.

[0118] Results: The hydrogenation peak area of the Au-Ni-Ce / NC catalyst prepared in Example 8 was 0.483 mA·V, which was 56.31% higher than that of Comparative Example 4; the exchange current density j0 was 2.516×10 -3 mA cm -2 , an increase of 15.46% compared with comparative example 4.

[0119] Comparative Example 5

[0120] Step 1) is the same as step 1) in Example 3;

[0121] Step 2) is the same as step 2) of comparative example 3, except that the Ni target is replaced with a Ti target to prepare an Au-Ti / C catalyst;

[0122] Step 3) is the same as step 3) of comparative example 3.

[0123] Results: The hydrogenation peak area of the Au-Ti / C catalyst prepared in Comparative Example 5 was 0.215 mA·V; the exchange current density j0 was 0.937×10 -3 mA cm -2 .

[0124] Embodiment 9

[0125] Step 1) is the same as step 1) in Example 3;

[0126] Step 2) is the same as step 2) of Example 7, except that the Ni target is replaced with a Ti target to prepare an Au-Ti / NC catalyst;

[0127] Step 3) is the same as step 3) of comparative example 3.

[0128] Results: The hydrogenation peak area of the Au-Ti / NC catalyst prepared in Example 9 was 0.277 mA·V, which was 28.83% higher than that in Comparative Example 5; the exchange current density j0 was 1.217×10 -3 mA cm -2 , an increase of 29.88% compared with comparative example 5.

[0129] Comparative Example 6

[0130] Step 1) is the same as step 1) in Example 3;

[0131] Step 2) is the same as step 2) of comparative example 4, except that the Ni target is replaced with a Ti target to prepare an Au-Ti-Ce / C catalyst;

[0132] Step 3) is the same as step 3) of comparative example 3.

[0133] Results: The hydrogenation peak area of the Au-Ti-Ce / C catalyst prepared in Comparative Example 6 was 0.453 mA·V; the exchange current density j0 was 1.133×10 -3 mA cm -2 .

[0134] Example 10

[0135] Step 1) is the same as step 1) in Example 3;

[0136] Step 2) is the same as step 2) of Example 8, except that the Ni target is replaced with a Ti target to prepare the Au-Ti-Ce / NC catalyst;

[0137] Step 3) is the same as step 3) of comparative example 3.

[0138] Results: The hydrogenation peak area of the Au-Ti-Ce / NC catalyst prepared in Example 10 was 0.849 mA·V, which was 87.41% higher than that in Comparative Example 6; the exchange current density j0 was 1.392×10 -3 mA cm -2 , an increase of 22.85% compared with comparative example six.

[0139] Figure 1 The full spectrum of Comparative Example 1 and Example 1 in the 0-1400 eV range shows diffraction peaks for C, O, and N, indicating successful introduction of nitrogen onto the carbon material surface. The surface element content (at%) of the samples was calculated using CasaXPS software. The surface element content of Comparative Example 1 was 94.49 at%, O 3.72 at%, and N 1.79 at%, while the surface element content of Example 1 was 79.38 at%, O 6.73 at%, and N 13.89 at%. After 180 s of N emission, the surface element content of the sample was 94.49 at%, O 3.72 at%, and N 1.79 at%.+ After beam bombardment, the surface nitrogen content of Example 1 is increased by 675.97% compared with that of Comparative Example 1.

[0140] Figure 2 The C1s spectrum of element C in Comparative Example 1 and Example 1 ( Figure 2 1 and 4), can be fitted into three peaks, the three peak areas are the total area of C1s, where the peak area represents the relative atomic content of the corresponding chemical state. The sample is subjected to peak fitting by CasaXPS software, the corresponding chemical state is determined according to the binding energy, and the relative atomic content of the corresponding chemical state is calculated. The three peaks of comparative example 1 appear at the binding energies of 284.80eV, 285.87eV and 286.82eV, which are CC (81.69at%, Figure 2 2), CN (13.11at%, Figure 2 3) and CO (5.20at%, Figure 2 4). The three peaks of Example 1 appear at 284.80eV (CC 71.14at%, Figure 2 6), 286.23eV (CN 22.10at%, Figure 2 7) and 287.92eV (CO 6.76at%, Figure 2 8) binding energy. The appearance of CN further demonstrates the successful introduction of N onto the sample surface. Furthermore, the CN content in Example 1 is 40.67% higher than that in Comparative Example 1. It can be seen that compared with Comparative Example 1, the CN peak in Example 1 shifts by 0.36 eV toward higher binding energy. This is because the electronegativity of N is higher than that of C. The large amount of N introduced causes electrons from C to transfer to the N atoms, thereby shifting the electronegativity of CN toward higher binding energy.

[0141] Figure 3 is the N1s spectrum of the N element in Comparative Example 1 and Example 1 ( Figure 3 1 and 4), can be fitted into three peaks, the three peak areas are the total area of N1s, where the peak area represents the relative atomic content of the corresponding chemical state. The sample is subjected to peak fitting by CasaXPS software, the corresponding chemical state is determined according to the binding energy, and the relative atomic content of the corresponding chemical state is calculated. The three peaks of comparative example 1 appear at 399.08eV, 400.17eV and 402.82eV binding energies, which are pyridine nitrogen (10.70at%, Figure 3 2), graphitic nitrogen (71.39at%, Figure 3 3) and N-oxide species (17.91at%, Figure 3 4). The three peaks of Example 1 appear at 399.01eV (pyridine nitrogen 59.02at%, Figure 36), 400.90eV (graphitic nitrogen 34.45at%, Figure 3 7) and 403.05eV (N- oxide species 6.53at%, Figure 3 8) binding energy. After nitrogen doping treatment, the surface nitrogen species of Comparative Example 1 and Example 1 are the same, while the content of pyridinic nitrogen in Example 1 is increased, indicating that the introduced nitrogen on the surface of Example 1 is mostly in the form of pyridinic nitrogen. Pyridinic nitrogen can serve as an anchoring point for subsequent metal deposition, thereby increasing the stability and dispersibility of the metal. At the same time, pyridinic nitrogen increases the structural defects of the support, which is beneficial to the adsorption of the hydrogenation substrate on the catalyst surface.

[0142] Figure 4 The hydrogen evolution CV curves of Comparative Example 2, Example 3, Example 5, and Example 6 are shown in the accompanying drawings. The hydrogen evolution peak areas calculated based on the hydrogen evolution peaks are 0 mA·V, 0 mA·V, 0.0148 mA·V, and 0.473 mA·V, respectively, indicating that nitrogen doping improves the hydrogen evolution performance of the samples.

[0143] Figure 5 The LSV curves of Comparative Example 2, Example 3, Example 5, and Example 6 are shown in Table 2. The exchange current density i0 of the samples calculated according to Formula 2 is 0.307 mA cm -2 , 0.405mA cm -2 、11.808mA cm -2 and 27.951 mA cm -2 , indicating that nitrogen doping increases the rate of hydrogen evolution reaction of the sample.

[0144] Figure 6 The hydrogenation CV curves of Comparative Example 3, Example 7, Comparative Example 4, and Example 8 show that the hydrogenation peak areas of the samples are 0.396 mA·V, 0.682 mA·V, 0.309 mA·V, and 0.483 mA·V, respectively, indicating that nitrogen doping improves the hydrogenation performance of the samples.

[0145] Figure 7 The Tafel curves of Comparative Example 3, Example 7, Comparative Example 4 and Example 8 are calculated using the extrapolation method to calculate the exchange current density j0 of the samples: 1.697×10 -3 mA cm -2 , 2.071×10 -3 mA cm -2 , 2.179×10 -3 mAcm -2 and 2.516×10 -3 mA cm -2 , indicating that nitrogen doping increases the rate of hydrogenation reaction of the sample.

[0146] Comparative Example 7

[0147] Step 1) is the same as step 1) in Example 3;

[0148] Step 2) is the same as step 2) of Example 3, except that the bombardment time is 240 seconds, that is, the nitrogen doping treatment is performed for 240 seconds;

[0149] Step 3) The nitrogen-doped graphite fiber cloth prepared in step 2) is cut into a size of 3×4 cm, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0150] Results: The nitrogen-doped graphite fiber cloth prepared in Comparative Example 7 did not show a hydrogen evolution peak, and the exchange current density i0 was 0.342 mA cm -2 , the exchange current density is increased by 11.40% compared with the comparative example 2.

[0151] Comparative Example 8

[0152] Step 1) is the same as step 1) in Example 3;

[0153] Step 2) is the same as step 2) of Example 3, except that the beam intensity during bombardment is 60 mA.

[0154] Step 3) The nitrogen-doped graphite fiber cloth prepared in step 2) is cut into a size of 3×4 cm, and a piece of sample is randomly selected for hydrogen evolution CV and LSV tests to obtain the hydrogen evolution peak area and exchange current density i0 of the sample.

[0155] Results: The nitrogen-doped graphite fiber cloth prepared in Comparative Example 8 did not show a hydrogen evolution peak, and the exchange current density i0 was 0.327 mA cm -2 , the exchange current density is increased by 6.51% compared with the comparative example 2.

[0156] The above are merely preferred embodiments of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. Application of a nitrogen-doped carbon material as an Au-based catalyst carrier, characterized in that: The Au-based catalyst is Au, Au-Ni, Au-Ti, Au-Ni-Ce or Au-Ti-Ce; a nitrogen-doped carbon material is used as a substrate, and a sputtering ion source is used to introduce Ar + The nitrogen-doped carbon-supported Au-based catalyst was prepared by bombarding Au target, Au target-Ni target, Au target-Ti target, Au target-Ni target-Ce target or Au target-Ti target-Ce target with a beam current of 70 mA, an acceleration of 140 V and a sputtering time of 900 s. The nitrogen-doped carbon material uses an auxiliary ion source to induce low-intensity divergent N + The beam bombards the surface of the carbon material, making N + Replace the C atoms on the surface of the carbon material to obtain nitrogen-doped carbon material; use the auxiliary ion source to induce low-intensity divergent N + The beam intensity is 40 mA; the nitrogen content in the nitrogen-doped carbon material is 6.02-13.89 at %; The method for preparing the nitrogen-doped carbon material comprises the following steps: 1) placing the carbon material in 0.5 mol / L sulfuric acid, acetone, and deionized water in sequence for ultrasonic cleaning, and dehydrating and drying to obtain a pretreated carbon material; 2) When the vacuum chamber pressure reaches 3.0×10 -2 Pa, the sample stage was heated to 210 °C and the vacuum chamber pressure reached 8.0 × 10 -4 Pa, the auxiliary ion source is turned on to induce the divergence of N + The beam was used to assist in cleaning the surface of the pretreated carbon material. The parameters during the auxiliary cleaning process were: cathode 16.2-16.5A, anode 53-61V, screen voltage 0.5kV, beam current 50mA, acceleration 200V, and time 300s. After cleaning, adjust the screen pressure to make the divergent N + The beam intensity is reduced, and low-intensity N is used. + The carbon material is bombarded with a beam with the bombardment parameters of: cathode 15.9-17A, anode 54-56V, screen voltage 0.35kV, beam 40mA, acceleration 200V, sputtering time 90-180s, thereby obtaining nitrogen-doped carbon material.

2. The use according to claim 1, characterized in that The carbon material is graphite fiber cloth or graphite sheet.

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