A method for preparing non-noble metal multi-atom co-doped molybdenum disulfide and its application

Abstract

This invention discloses a method for preparing non-noble metal multi-atom co-doped molybdenum disulfide. Specifically, the method first involves uniformly mixing a precursor solution with multiple doped metal atoms with a molybdenum source solution, then reacting it with a sulfur-containing compound at a certain temperature. Finally, after solution treatment, the product is obtained by filtration and drying. The material prepared by this method has a well-defined structure, a single crystalline phase, and no metal atom clusters or non-molybdenum disulfide formation. The type and content of the incorporated non-noble metal heteroatoms are easily controlled. Experimental results have verified that this material exhibits excellent electrocatalytic hydrogen evolution reaction performance and has the potential to replace noble metal catalysts. This method is a universal method for preparing non-noble metal multi-atom co-doped molybdenum disulfide, characterized by its simple operation and ease of control.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of two-dimensional nanomaterials, and particularly relates to a non-noble metal multi-atom co-doped molybdenum disulfide preparation method and application thereof. BACKGROUND

[0002] In recent years, two-dimensional (2D) materials have attracted extensive attention in catalysis and other fields due to their unique structure and electronic properties (Y. Wang, D. H. Deng, X. H. Bao et al., Chem. Rev., 119, 1806-1854 (2019)). Transition metal dichalcogenides (TMDs) are one of the representative two-dimensional materials, which have a two-dimensional structure similar to graphene, and TMDs can be directly applied as catalysts in many reaction processes (L. Tang, D. H. Deng, X. H. Bao et al., Confinement Catalysis with 2D Materials for Energy Conversion. Adv. Mater. 31, 1901996 (2019)). On this basis, the electronic structure and catalytic activity of TMDs can also be regulated by methods such as manufacturing defects (J. F. Xie, Yi Xie et al., Adv. Mater. 25, 5807-5813 (2013)), compounding (X. Y. Meng, D. H. Deng, X. H. Bao et al., Nano Energy 61, 611-616 (2019)) and doping (S. Z. Yang, W. Zhou et al., Adv. Mater. 30, 1803477 (2018), J. Deng, D. H. Deng, X. H. Bao et al., Energy & Environmental Science 8, 1594-1601 (2015)). In addition, the form of TMDs also has a great influence on the catalytic activity. Compared with bulk materials, ultra-thin two-dimensional materials will expose more atomic surfaces under the same mass conditions (J. Deng, D. H. Deng, X. H. Bao et al., RSC Advances, 4, 34733-34738 (2014)), greatly improving the specific surface area, which provides more options for us to better optimize and design high-activity catalysts.

[0003] It has been reported that molybdenum disulfide (MoS2) has excellent activity for electrocatalytic hydrogen evolution reaction (HER) (Thomas F., Ib Chorkendorff et al., Science 317, 100 (2007)), but only a few unsaturated S atoms on the edge of MoS2 are used for simulation calculation to show that it has potential high HER activity, but most of them are in-plane saturated and inert S atoms. Theoretical calculation and experimental results show that MoS2 preferentially exposes the thermodynamically stable (002) basal plane (J.F. Xie, Yi Xie et al., Adv. Mater. 25, 5807-5813 (2013)), which greatly limits the application of MoS2 in HER reaction. The purpose of the above-mentioned doping is to change the local electronic structure by doping heteroatoms into molybdenum disulfide, greatly increasing the number of coordinated unsaturated sulfur atoms, thereby improving its hydrogen evolution activity. However, the current doping strategy is mostly single-atom or noble metal atom doping, which not only has limited activity regulation for molybdenum sulfide, but also has high cost of noble metals, greatly limiting the wide application of doping strategy. Therefore, non-noble metal multi-atom co-doping of molybdenum disulfide becomes a potential high-efficiency activity regulation strategy. However, in the process of co-doping multiple atoms, it is necessary to ensure that the original "sandwich" structure (S-Mo-S) of molybdenum disulfide is not destroyed and the aggregation of multiple heteroatoms to form a new phase is avoided. Therefore, the preparation of non-noble metal multi-atom co-doped molybdenum disulfide has great challenges. SUMMARY

[0004] Based on the above background technology, the present application aims to provide a preparation method of non-noble metal multi-atom co-doped molybdenum disulfide. The method co-dopes multiple elements into molybdenum disulfide by in-situ doping method. The doped molybdenum disulfide prepared by the method has excellent activity for electrocatalytic hydrogen evolution reaction. The atoms doped by the method contain two or more than two, which are non-noble metal multi-atom co-doping. The method is simple to operate and has a wide range of applications. The material has a broad application prospect in the fields of electrocatalysis and energy chemistry through doping regulation.

[0005] In order to achieve the above-mentioned purpose, the technical scheme of the present application is as follows:

[0006] In one aspect, the present application provides a multi-atom co-doped molybdenum disulfide, which is co-doped with two or more than two atoms, wherein the atoms are non-noble metal atoms.

[0007] Based on the above technical scheme, further, the non-noble metal is titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, and cadmium; and the atom-doped molybdenum disulfide is in a tubular, linear, spherical, sheet, three-dimensional foam or flower-like structure.

[0008] The application further provides a preparation method of the non-noble metal multi-atom co-doped molybdenum disulfide, comprising the following steps:

[0009] (1) adding a molybdenum source into a solvent to obtain A liquid, adding a doped non-noble metal atom precursor and a chelating agent into a solvent, stirring at 15-90℃ for 0.5-24h to obtain B liquid;

[0010] (2) adding the A liquid obtained in step (1) into the B liquid, mixing, mixing with a sulfur source under inert gas protection and sealing in a high-pressure reaction kettle, heating to 100-600℃ and keeping for 1-24h;

[0011] (3) treating the product obtained in step (2) in a solution for 1-16h, washing, suction filtering and drying to obtain the non-noble metal multi-atom co-doped molybdenum disulfide.

[0012] Based on the above technical scheme, further, in step (1), the molybdenum source is at least one of sodium molybdate, molybdenum chloride, molybdenum trioxide, ammonium molybdate, potassium molybdate, molybdenum phosphate, ammonium tetrathiomolybdate, molybdenum acetate, molybdenum oxalate, molybdenum acetylacetone, and molybdenum phosphide; the sulfur source is at least one of sulfur powder, thiourea, thioacetamide, carbon disulfide, sodium sulfide, potassium sulfide, ammonium tetrathiomolybdate, butanethiol, dimethyl sulfoxide, and potassium thiocyanate; and the chelating agent is at least one of ethylenediaminetetraacetic acid, amino triacetic acid, tartaric acid, gluconic acid, sodium citrate, citric acid monohydrate, ammonium citrate, and hydroxyethyl ethylenediamine triacetate.

[0013] Based on the above technical scheme, further, the molar ratio of molybdenum atoms in the molybdenum source to non-noble metal atoms is 10:0.1-20; the molar ratio of any two atoms in the doped non-noble metal atoms is 1:20-20:1; and the molar ratio of any one of the non-noble metal atoms to the chelating agent is 0.1-10; in step (2), the molar ratio of molybdenum atoms in the molybdenum source to sulfur atoms in the sulfur source is 1:500-10:1.

[0014] Based on the above technical scheme, further, in step (1), the chelating agent is added into the non-noble metal atom precursor solution and ultrasonically dispersed; in step (2), the molybdenum source aqueous solution and the non-noble metal atom precursor solution are mixed during the mixing process, and are dispersed in an ultrasonic water bath, with each ultrasonic dispersion time being 0.5-6h.

[0015] Based on the above technical scheme, further, in step (1), the solvent is at least one of water, methanol, formic acid, toluene, and cyclohexane.

[0016] Based on the above technical scheme, further, in step (2), the inert gas is at least one of helium, nitrogen, argon, and neon; and the heating rate is 0.5-40℃ / min.

[0017] Based on the above technical scheme, further, in step (3), the solution is at least one of sodium hydroxide solution, potassium hydroxide solution, toluene solution, ethanol solution, hydrochloric acid solution; wherein the concentration of sodium hydroxide solution, potassium hydroxide solution, ethanol solution, hydrochloric acid solution is 5-50wt%, the concentration of toluene solution is 20-70wt%; the washing is washed in ultrapure water and ethanol until the solution is neutral; the drying temperature is 25-150℃, and the drying time is 4-24h.

[0018] In addition, the application also provides the application of the above-mentioned non-noble metal multi-atom co-doped molybdenum disulfide or the non-noble metal multi-atom co-doped molybdenum disulfide obtained by the above-mentioned preparation method in an electrocatalytic hydrogen evolution reaction.

[0019] The application has the following beneficial effects:

[0020] 1. The prepared non-noble metal multi-atom co-doped molybdenum disulfide material has a clear structure, a single crystal phase, and the doped atoms are uniformly distributed in the material without the formation of single metal clusters or metal particles.

[0021] 2. The prepared non-noble metal multi-atom co-doped molybdenum disulfide material has a rich variety of metal heteroatoms that can be used, and the ratio between components can be controlled within a wide range.

[0022] 3. The added chelating agent in the prepared non-noble metal multi-atom co-doped molybdenum disulfide can significantly improve its performance in hydrogen production by electrolysis of water in an acidic environment.

[0023] 4. The preparation process of the prepared non-noble metal multi-atom co-doped molybdenum disulfide is simple, easy to control, easy to scale up, the required precursors are widely available, and the prepared material has good catalytic stability and good industrial application prospects. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 a is a transmission electron microscope (TEM) image of the sample of Comparative Example 1, and 1b is a partial enlarged view;

[0025] Figure 2 a is a transmission electron microscope (TEM) image of the sample of Example 1, and 2b is a partial enlarged view;

[0026] Figure 3 X-ray diffraction spectrum (XRD) of the samples of Examples 1, 2 and 4, and Comparative Example 1;

[0027] Figure 4 Electrocatalytic hydrogen evolution activity test diagram of Examples 1, Comparative Example 1 and Comparative Example 2 under acidic conditions. DETAILED DESCRIPTION

[0028] The whole material preparation process is described in detail below through specific examples. Meanwhile, the examples only give part of the conditions for realizing material preparation, and do not mean that these conditions must be met to achieve the purpose, and the scope of the claims of the present application is not limited by the examples.

[0029] Comparative Example 1

[0030] (1) 0.9 g of ammonium molybdate was dissolved in 20 mL of water, and after ultrasonic dispersion, 10 mL of carbon disulfide was sealed into a 60 mL high-pressure reaction kettle under argon protection;

[0031] (2) The high-pressure kettle in (1) was placed at 400℃ for 4 h;

[0032] (3) The sample obtained in (2) was treated with 6 mol / L NaOH solution at 60℃ for 3 h, and then washed with ultrapure water and ethanol and suction filtered. -1

[0033] (4) The sample obtained in (3) was placed in a 80℃ oven for drying, to obtain few-layer molybdenum disulfide (FL-MoS2).

[0034] Comparative Example 2

[0035] (1) 0.9 g of ammonium molybdate was dissolved in 10 mL of water, and after ultrasonic dispersion, 17 mL of distilled water was taken in a 20 mL sample bottle, followed by adding 0.1417 g of iron nitrate nonahydrate and 0.0972 g of cobalt nitrate hexahydrate, stirring for 0.5 h to obtain B liquid; then 3 mL of the above A liquid was slowly added to the B liquid, stirring for 10 min, and then 10 mL of carbon disulfide was sealed into a 60 mL high-pressure reaction kettle under argon protection;

[0036] (2) The high-pressure kettle in (1) was placed at 400℃ for 4 h.

[0037] (3) The sample obtained in (2) was treated with 6 mol / L NaOH solution at 60℃ for 3 h, and then washed with ultrapure water and ethanol and suction filtered. -1

[0038] (4) The sample obtained in (3) was placed in a 80℃ oven for drying, to obtain iron and cobalt co-doped molybdenum disulfide (8Fe8Co-MoS2).

[0039] Comparative Example 3

[0040] (1) 0.9 g of ammonium molybdate and 0.3226 g of cobalt nitrate hexahydrate were dissolved in 20 mL of water, and after ultrasonic dispersion, 0.2169 g of ferrocene was added to 10 mL of carbon disulfide, stirring for 0.5 h to obtain B liquid; under argon protection, the A and B liquids were mixed and sealed into a 60 mL high-pressure reaction kettle;​​

[0041] (2) The autoclave in (1) is placed at 400°C for 4h;

[0042] (3) The sample obtained in (2) is treated with 6mol L-1 NaOH solution at 60°C for 3h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0043] (4) The sample obtained in (3) is dried in an 80°C oven to obtain iron-cobalt co-doped molybdenum disulfide (8Fe8Co-MoS2-ferrocene).

[0044] Comparative Example 4

[0045] (1) 0.9g ammonium molybdate is dissolved in 10mL water, ultrasonic dispersion, uniform after A liquid, take 10mL distilled water in 20mL sample bottle, then add 0.4709g iron nitrate nonahydrate and 0.2372g copper nitrate 2.5 water, stirring 0.5h, for B liquid; again, the above A liquid, slowly added to B liquid, stirring 10min, and 10mL carbon disulfide is sealed to 60mL high pressure reaction kettle under argon protection;

[0046] (2) The autoclave in (1) is placed at 400°C for 4h;

[0047] (3) The sample obtained in (2) is treated with 6mol L-1 NaOH solution at 60°C for 3h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0048] (4) The sample obtained in (3) is dried in an 80°C oven to obtain iron-cobalt co-doped molybdenum disulfide (8Fe8Cu-MoS2).

[0049] Comparative Example 5

[0050] (1) 0.9g ammonium molybdate is dissolved in 10mL water, ultrasonic dispersion, uniform after A liquid, take 10mL distilled water in 20mL sample bottle, then add 0.4709g iron nitrate nonahydrate and 0.3234g nickel nitrate hexahydrate, stirring 0.5h, for B liquid; again, the above A liquid, slowly added to B liquid, stirring 10min, and 10mL carbon disulfide is sealed to 60mL high pressure reaction kettle under argon protection;

[0051] (2) The autoclave in (1) is placed at 400°C for 4h;

[0052] (3) The sample obtained in (2) is treated with 6mol L-1 NaOH solution at 60°C for 3h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0053] ​​​(4) The sample obtained in (3) is dried in an oven at 80°C to obtain iron-nickel co-doped molybdenum disulfide (8Fe8Ni-MoS2).

[0054] Comparative Example 6

[0055] (1) Dissolve 0.9g ammonium molybdate in 10mL of water, disperse by ultrasonication, and after uniform dispersion, it becomes solution A. Take 10mL of distilled water into a 20mL sample bottle, then add 0.3234g nickel nitrate hexahydrate and 0.3226g cobalt nitrate hexahydrate, stir for 0.5h, and it becomes solution B. Then slowly add the above solution A into solution B, stir for 10min, and then seal it with 10mL of carbon disulfide into a 60mL high-pressure reactor under argon protection.

[0056] (2) Place the autoclave in (1) at 400℃ for 4 hours;

[0057] (3) The sample obtained in (2) is heated in 6 mol L -1 The solution was treated with sodium hydroxide at 60°C for 3 hours, then washed with ultrapure water and ethanol and filtered.

[0058] (4) The sample obtained in (3) is dried in an oven at 80°C to obtain nickel-cobalt co-doped molybdenum disulfide (8Ni8Co-MoS2).

[0059] Example 1

[0060] (1) Dissolve 0.9g ammonium molybdate in 10mL of water, disperse by ultrasonication, and obtain solution A after homogeneity. Take 17mL of distilled water into a 20mL sample bottle, add 0.2450g citric acid monohydrate, stir to dissolve, then add 0.1417g ferric nitrate nonahydrate and 0.0972g cobalt nitrate hexahydrate, stir for 0.5h to obtain solution B. Take 3mL of the above solution A and slowly add it to solution B, stir for 10min, and then seal it with 10mL of carbon disulfide in a 60mL high-pressure reactor under argon protection.

[0061] (2) Place the autoclave in (1) at 400℃ for 4 hours;

[0062] (3) The sample obtained in (2) is heated in 6 mol L -1 The sample was treated with sodium hydroxide solution at 60°C for 3 hours. Then it was washed with ultrapure water and ethanol and filtered.

[0063] (4) The sample obtained in (3) is dried in an oven at 80°C to obtain iron-cobalt co-doped molybdenum disulfide (8Fe8Co-MoS2-CA).

[0064] Figure 2 This is a transmission electron microscope (TEM) image of the iron-cobalt co-doped molybdenum disulfide prepared in Example 1. Figure 2It can be seen that the sample is a two-dimensional layered structure, and exposes a uniform surface and rich edges, without other clusters or impurities. Figure 3 The X-ray diffraction spectrum of the sample shows that the obtained sample is composed of 2H phase molybdenum sulfide, and no diffraction peak related to the doped metal appears in a certain doping atom concentration range, further proving that there is no agglomeration phenomenon between the various doped elements, and that the doped elements do not form a new independent crystal phase structure, which is consistent with the TEM result.

[0065] Example 2

[0066] (1) 0.9 g of ammonium molybdate was dissolved in 10 mL of water, ultrasonic dispersion, and then 17 mL of distilled water was taken in a 20 mL sample bottle, 0.490 g of citric acid was added, stirred and dissolved, then 0.1417 g of iron nitrate nonahydrate and 0.0972 g of cobalt nitrate hexahydrate were added, stirred for 0.5 h, and then 3 mL of the above A liquid was slowly added to the B liquid, stirred for 10 min, and then 10 mL of carbon disulfide was sealed in a 60 mL high-pressure reaction kettle under argon protection;

[0067] (2) The high-pressure kettle in (1) was placed at 400°C for 4 h;

[0068] (3) The sample obtained in (2) was treated with 6 mol / L NaOH solution at 60°C for 3 h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0069] (4) The sample obtained in (3) was placed in a 80°C oven for drying to obtain iron and cobalt co-doped molybdenum disulfide (8Fe8Co-MoS2-2CA).

[0070] Example 3

[0071] (1) 0.9 g of ammonium molybdate was dissolved in 10 mL of water, ultrasonic dispersion, and then 17 mL of distilled water was taken in a 20 mL sample bottle, 0.490 g of citric acid was added, stirred and dissolved, then 0.1417 g of iron nitrate nonahydrate and 0.0972 g of cobalt nitrate hexahydrate were added, stirred for 0.5 h, and then 3 mL of the above A liquid was slowly added to the B liquid, stirred for 10 min, and then 10 mL of carbon disulfide was sealed in a 60 mL high-pressure reaction kettle under argon protection;

[0072] (2) The high-pressure kettle in (1) was placed at 400°C for 4 h;

[0073] (3) The sample obtained in (2) was treated with 6 mol / L NaOH solution at 60°C for 3 h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0074] ​​(4) The sample obtained in (3) is placed in a 80°C oven for drying to obtain iron and cobalt co-doped molybdenum disulfide (8Fe8Co-MoS2-4CA).

[0075] Example 4

[0076] (1) 0.9 g of ammonium molybdate is dissolved in 10 mL of water, ultrasonic dispersion, and then 17 mL of distilled water is taken in a 20 mL sample bottle, 0.2450 g of citric acid monohydrate is added, stirred and dissolved, then 0.2834 g of iron nitrate nonahydrate and 0.1944 g of cobalt nitrate hexahydrate are added, stirred for 0.5 h, and then 3 mL of the above A liquid is slowly added to the B liquid, stirred for 10 min, and then 10 mL of carbon disulfide is sealed in a 60 mL high-pressure reaction kettle under argon protection;

[0077] (2) The high-pressure kettle in (1) is placed at 400°C for 4 h;

[0078] (3) The sample obtained in (2) is treated with 6 mol / L NaOH solution at 60°C for 3 h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0079] (4) The sample obtained in (3) is placed in a 80°C oven for drying to obtain iron and cobalt co-doped molybdenum disulfide (16Fe16Co-MoS2-CA).

[0080] Example 5

[0081] (1) 0.9 g of ammonium molybdate is dissolved in 10 mL of water, ultrasonic dispersion, and then 17 mL of distilled water is taken in a 20 mL sample bottle, 0.2450 g of citric acid monohydrate is added, stirred and dissolved, then 0.2834 g of iron nitrate nonahydrate and 0.1944 g of cobalt nitrate hexahydrate are added, stirred for 0.5 h, and then 3 mL of the above A liquid is slowly added to the B liquid, stirred for 10 min, and then 10 mL of carbon disulfide is sealed in a 60 mL high-pressure reaction kettle under argon protection;

[0082] (2) The high-pressure kettle in (1) is placed at 400°C for 4 h;

[0083] (3) The sample obtained in (2) is treated with 6 mol / L NaOH solution at 60°C for 3 h, and then washed with ultrapure water and ethanol and suction filtered; -1

[0084] (4) The sample obtained in (3) is placed in a 80°C oven for drying to obtain iron and cobalt co-doped molybdenum disulfide (4Fe8Co-MoS2-CA).

[0085] Example 6

[0086] ​​(1) Dissolve 0.9g ammonium molybdate in 10mL of water, disperse by ultrasonication, and after uniformity, it becomes solution A. Take 17mL of distilled water into a 20mL sample bottle, add 0.2450g citric acid monohydrate, stir to dissolve, then add 0.1417g ferric nitrate nonahydrate and 0.0486g cobalt nitrate hexahydrate, stir for 0.5h, and it becomes solution B. Take 3mL of the above solution A, slowly add it to solution B, stir for 10min, and then seal it with 10mL of carbon disulfide in a 60mL high-pressure reactor under argon protection.

[0087] (2) Place the autoclave in (1) at 400℃ for 4 hours;

[0088] (3) The sample obtained in (2) is heated in 6 mol L -1 The solution was treated with sodium hydroxide at 60°C for 3 hours, then washed with ultrapure water and ethanol and filtered.

[0089] (4) The sample obtained in (3) is dried in an oven at 80°C to obtain iron-cobalt co-doped molybdenum disulfide (8Fe4Co-MoS2-CA).

[0090] Example 7

[0091] The iron-cobalt co-doped molybdenum disulfide material with citric acid obtained in Example 1, the few-layer molybdenum disulfide material in Comparative Example 1, and the iron-cobalt co-doped molybdenum disulfide material without citric acid obtained in Comparative Example 2 were used as catalysts for the electrocatalytic hydrogen evolution reaction. The effects of the presence or absence of citric acid and the presence or absence of non-noble metal atoms doped molybdenum disulfide on the electrocatalytic hydrogen evolution activity were investigated.

[0092] 1. Evaluation method for electrocatalytic hydrogen evolution performance: A linear voltammetric experiment was conducted using a three-electrode system. The reference electrode was an Ag / AgCl electrode, the counter electrode was a carbon rod electrode, and the electrolyte was 0.5 mol / L argon-saturated electrolyte. -1 For the sulfuric acid solution, a 5mm glassy carbon electrode was selected as the working electrode. The catalyst electrode preparation method is as follows:

[0093] Add 1 mL of ethanol solution to 4 mg of sample, then add 20 μL of 5 wt% Nafion solution and ultrasonically disperse until a slurry is formed. Then take 25 μL of the above slurry and apply it to the surface of a glassy carbon electrode, and let it air dry for later use.

[0094] 2. Test conditions: At 25℃, a rotating disk electrode was used at a rotation speed of 1600 rpm, with a voltage of 2 mV / s. -1 It is performed at a linear scan rate.

[0095] 3. Test results: iron-cobalt co-doped molybdenum disulfide exhibits excellent electrocatalytic activity in an acidic medium in the presence of citric acid, and the hydrogen evolution performance is significantly improved compared to iron-cobalt doped molybdenum disulfide without the presence of citric acid. The hydrogen evolution activity order is as follows: iron-cobalt co-doped molybdenum disulfide-citric acid > iron-cobalt co-doped molybdenum disulfide > few-layer molybdenum disulfide.

[0096] By the preparation method of the present application, the doping of larger atomic weight in the molybdenum sulfide crystal lattice within a certain concentration range is successfully achieved, and the hydrogen evolution performance of few-layer molybdenum sulfide is improved. The electron microscope image shows that the obtained sample is a two-dimensional layered structure, and the uniform surface and abundant edges are exposed, without other clusters or impurities. The X-ray diffraction spectrum shows that the obtained sample is composed of 2H phase molybdenum sulfide, and within a certain doping atomic concentration range, no diffraction peak related to the doping metal appears, further proving that there is no agglomeration between the various doping elements, and the doping elements do not form a new independent crystal phase structure, which is consistent with the TEM result.

[0097] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement to part or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for producing an atomically doped molybdenum disulfide, characterized by, Molybdenum disulfide is doped with two or more than two atoms simultaneously, wherein the atoms are non-noble metal atoms; The method comprises the following steps: (1) adding a molybdenum source into a solvent to obtain A liquid, adding a doped non-noble metal atom precursor and a chelating agent into the solvent, stirring at 15-90 ℃ for 0.5-24 h to obtain B liquid; (2) adding the A liquid obtained in step (1) into the B liquid, mixing, mixing with a sulfur source under inert gas protection, and sealing in a high-pressure reaction kettle, heating to 100-600 ℃, and keeping for 1-24 h; (3) treating the product obtained in step (2) in a solution for 1-16 h, washing, suction filtering, and drying to obtain the non-noble metal multi-atom co-doped molybdenum disulfide; In step (1), the chelating agent is at least one of ethylenediaminetetraacetic acid, amino triacetic acid, tartaric acid, gluconic acid, sodium citrate, citric acid monohydrate, ammonium citrate, and hydroxyethyl ethylenediamine triacetic acid; In step (3), the solution is at least one of sodium hydroxide solution, potassium hydroxide solution, toluene solution, ethanol solution, and hydrochloric acid solution.

2. The method of claim 1, wherein the method is characterized by: The non-noble metal is titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, and cadmium; and the atom-doped molybdenum disulfide is in a tubular, linear, spherical, flaky, three-dimensional foam, or flower-like structure.

3. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. The molybdenum source is at least one of sodium molybdate, molybdenum chloride, molybdenum trioxide, ammonium molybdate, potassium molybdate, ammonium phosphomolybdate, molybdenum acetate, molybdenum oxalate, molybdenum acetylacetone, and molybdenum phosphide; The sulfur source is at least one of sulfur powder, thiourea, thioacetamide, carbon disulfide, sodium sulfide, potassium sulfide, ammonium tetrathiomolybdate, butanethiol, dimethyl sulfoxide, and potassium thiocyanate.

4. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. The molar ratio of molybdenum atoms in the molybdenum source to non-noble metal atoms is 10:0.1-20; and the molar ratio of any two atoms in the doped non-noble metal atoms is 1:20-20:1; The molar ratio of molybdenum atoms in the molybdenum source to sulfur atoms in the sulfur source is 1:500-10:1; The molar ratio of any one of the non-noble metal atoms to the chelating agent is 0.1-10.

5. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. In step (1), the chelating agent is ultrasonically dispersed in the doped non-noble metal atom precursor solution; and in step (2), the molybdenum source aqueous solution and the non-noble metal atom precursor solution are mixed and dispersed in an ultrasonic water bath during the mixing process, and each ultrasonic dispersion time is 0.5-6 h.

6. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. In step (1), the solvent is at least one of water, methanol, formic acid, toluene, and cyclohexane.

7. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. In step (2), the inert gas is at least one of helium, nitrogen, argon, and neon; and the heating rate is 0.5-40 ℃ / min.

8. The method of claim 1, wherein the molybdenum disulfide is doped with atoms of a transition metal. In step (3), the concentration of the sodium hydroxide solution, the potassium hydroxide solution, the ethanol solution, and the hydrochloric acid solution is 5-50 wt%, and the concentration of the toluene solution is 20-70 wt%; The washing is washing in ultrapure water and ethanol until the solution is neutral; the drying temperature is 25-150 ℃, and the drying time is 4-24 h.

9. Application of the atom-doped molybdenum disulfide obtained by the preparation method of any one of claims 1-8 in an electrocatalytic hydrogen evolution reaction.

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