Non-noble metal single-atom doped molybdenum carbide catalysts and methods of making same

Abstract

The application relates to a preparation method of a non-noble metal single-atom doped molybdenum carbide catalyst, wherein C3N4 is used as a self-sacrifice template, dopamine hydrochloride and alkali are sequentially added into a solvent A, then in-situ polymerization is carried out, a polydopamine layer is coated on the surface of the C3N4 to obtain a precursor A; a metal source is dissolved in a solvent B, then the precursor A is impregnated, and the solvent is evaporated to obtain a precursor B; the precursor B is subjected to heat treatment at 600-1200 DEG C under an inert gas atmosphere, and the non-noble metal single-atom doped molybdenum carbide catalyst is obtained. The application also relates to a molybdenum carbide-based hydrogenation catalyst prepared by the method, the activity component has high dispersity, a two-dimensional porous structure is beneficial to the adsorption and diffusion of reactants, the preparation method is simple and easy to implement, and the catalyst has excellent catalytic performance in selective hydrogenation of aromatic nitro compounds, selective hydrogenation of quinoline and the like.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of preparation and application of nanomaterials, and particularly relates to a hydrogenation catalyst and a preparation method thereof. BACKGROUND

[0002] The catalytic hydrogenation technology has been widely applied not only in petroleum chemical industry and petroleum refining, but also in medicine, fine chemical industry and other organic synthesis as a core technology. As the core of the catalytic hydrogenation technology, the development of high-performance hydrogenation catalyst has been widely concerned by researchers. At present, metal catalysts are mainly used in most catalytic hydrogenation reactions, which are mainly divided into two categories: noble metal and non-noble metal. The noble metal hydrogenation catalysts mainly include Pd, Pt, Ru and Ir, and the non-noble metal hydrogenation catalysts mainly include Fe, Co, Ni and Cu. The noble metal catalysts are widely used in industrial hydrogenation due to their excellent performance under mild conditions. However, the high cost and low reserves of the noble metal catalysts greatly restrict the development of related industries.

[0003] The traditional non-noble metal hydrogenation catalysts mainly include Ni-based, Co-based, Fe-based and Cu-based catalysts. However, due to the low Tamman temperature of these metals, the metals are prone to agglomeration during the preparation process, and it is difficult to highly disperse the metals on the surface of the carrier, resulting in a low density of active sites on the surface of the catalyst. In addition, according to the energy band theory, compared with noble metals (such as Pd, Pt and Ir), the number of "d-band holes" of non-noble metals is relatively large, which does not match the number of electron transfer required for H2 activation, resulting in a low intrinsic activity of the catalyst. Therefore, the hydrogenation reaction catalyzed by the non-noble metal catalyst usually needs to be carried out under high temperature and high pressure, and the high reaction temperature is easy to cause sintering and carbon deposition of the catalyst, thereby leading to deactivation of the catalyst. The whole process not only has high energy consumption, but also has a low safety factor of the reaction process. In addition, some fine chemicals with high added value are unstable under such harsh reaction conditions, thereby seriously limiting the application field of the non-noble metal catalyst.

[0004] In summary, in order to realize the cost reduction and efficiency increase of industrial production, and the efficient production of fine chemicals with high added value, it is an urgent problem to be solved in the chemical industry to develop a new type of high-performance non-noble metal hydrogenation catalyst. SUMMARY

[0005] The present application aims to avoid the shortcomings of the prior art and provide a molybdenum carbide-based hydrogenation catalyst with a two-dimensional sheet-shaped porous structure, a method for preparing the catalyst for hydrogenation reaction of nitro compounds and quinoline, which realizes high dispersion of molybdenum carbide and metal sites, and exhibits excellent performance in catalytic hydrogenation of aromatic nitro compounds and quinoline under mild conditions.

[0006] To achieve the above object, the technical scheme adopted by the present application is as follows: a preparation method of a non-noble metal single-atom doped molybdenum carbide catalyst, comprising the following steps:

[0007] Step one, preparation of precursor A:

[0008] First, disperse C3N4 in solvent A and ultrasonic for 10-120 minutes to obtain C3N4 solvent with a concentration of 10-100 g / L; then, add dopamine hydrochloride to the C3N4 solvent and add alkali under stirring at room temperature to obtain precursor solution A;

[0009] Then, after the obtained precursor solution A is subjected to polymerization reaction at a temperature of 25-80℃ for 0.5-72h, it is sequentially subjected to filtration, washing and drying to obtain precursor A;

[0010] The mass ratio of C3N4, dopamine hydrochloride and alkali is (0.1-5):(0.1-1):(0.1-1); and the solvent A is one or two of methanol, ethanol, isopropanol and water.

[0011] Step two, preparation of precursor B:

[0012] After the molybdenum source, metal source and precursor A are sequentially added to solvent B and mixed, the solvent B is removed by heating to 40-90℃, and then dried to obtain precursor B containing metal ions on the surface;

[0013] The mass ratio of the molybdenum source, metal source and precursor A is (1-10):(0.1-1):(10-100).

[0014] The solvent B is one or two of methanol, ethanol, isopropanol and water.

[0015] Step three, preparation of non-noble metal molybdenum carbide-based hydrogenation catalyst:

[0016] Under the condition of pure nitrogen or pure argon atmosphere, the precursor B is subjected to pyrolysis treatment, the pyrolysis treatment time is 0.5-6h, the heating rate is 0.5-20℃ / min, and after the pyrolysis treatment temperature is raised to 600-1200℃, the temperature is lowered, and the non-noble metal molybdenum carbide-based hydrogenation catalyst is obtained after the temperature is lowered to room temperature.

[0017] Further, the alkali in step one is one or any two of ammonium carbonate, ammonium bicarbonate, ammonia, diethylamine and tris-hydroxymethyl aminomethane.

[0018] Further, the molybdenum source in step two is any one of ammonium molybdate, sodium molybdate, molybdenum chloride, phosphomolybdic acid, molybdic acid and molybdenum acetylacetone.

[0019] Further, the metal source in step two is one or two of Fe source, Co source, Ni source and Cu source.

[0020] Further, the Fe source in the metal source is derived from ferric nitrate or ferric acetate or iron acetylacetonate or ferric chloride; the Co source in the metal source is derived from cobalt acetylacetonate or cobalt chloride or cobalt nitrate or cobalt acetate; the Ni source in the metal source is derived from nickel acetylacetonate or nickel chloride or nickel nitrate or nickel acetate; and the Cu source in the metal source is derived from copper chloride or copper nitrate or copper acetate or copper acetylacetonate.

[0021] Further, the solvent A is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1-1).

[0022] Further, the solvent B is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1-1).

[0023] Further, the catalytically active component is a two-dimensional sheet structure molybdenum carbide catalyst doped with iron or cobalt or nickel or copper atoms.

[0024] The beneficial effects of the present application are:

[0025] The method provided by the present application can effectively avoid the agglomeration of the metal in the preparation process of the catalyst by using the strong interaction between the molybdenum carbide formed in situ during the pyrolysis process and the metal source (Fe, Co, Ni or Cu), realizing the high dispersion of the metal sites, and realizing the doping of the metal atoms (Fe, Co, Ni or Cu) into the crystal lattice of the molybdenum carbide, and the strong electronic interaction between the metal and the molybdenum carbide, which effectively modulates the electronic properties of the active sites on the surface of the catalyst, thereby improving the intrinsic activity of the catalyst, and the preparation method is simple and easy to implement, suitable for industrial large-scale production, and expected to replace Raney nickel catalyst for application in the synthesis of related chemicals, and has good application prospect.

[0026] The catalyst provided by the present application uses C3N4 with a two-dimensional sheet structure as a self-sacrificial template, uses the characteristics that C3N4 decomposes and releases small gas molecules at a higher temperature, constructs a molybdenum carbide-based hydrogenation catalyst with a two-dimensional sheet porous structure, which is beneficial to the exposure of the active sites on the surface of the catalyst, and the adsorption and diffusion of molecules in the reaction process, so that the catalyst has excellent catalytic hydrogenation performance, and does not ignite when encountering air, and is convenient to store. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 Fe-MoC prepared for example 1 of the present application 1-x TEM image of CN-700 catalyst;

[0028] Figure 2Co-MoC prepared for the present embodiment 2 1-x @Scanning electron micrograph of CN-700 catalyst

[0029] Figure 3 Co-MoC prepared for the present embodiment 2 1-x @Transmission electron micrograph of CN-700 catalyst

[0030] Figure 4 Co-MoC prepared for the present embodiment 3 1-x @X-ray diffraction pattern of CN-600 catalyst

[0031] Figure 5 Fe-MoC prepared for the present embodiment 4 1-x @X-ray diffraction pattern of CN-800 catalyst DETAILED DESCRIPTION

[0032] The principles and features of the present application are described below in conjunction with the accompanying drawings, which are only used to explain the present application and are not intended to limit the scope of the present application.

[0033] In order to achieve the above-mentioned purpose, the present application provides the following detailed embodiments:

[0034] Embodiment 1: A preparation method of a non-noble metal single-atom doped molybdenum carbide catalyst, comprising the following steps:

[0035] Step one, preparation of precursor A:

[0036] First, disperse C3N4 in solvent A and ultrasonic for 10-120 minutes to obtain a C3N4 solvent with a concentration of 10-100 g / L; then, add dopamine hydrochloride to the C3N4 solvent and add a base under stirring at room temperature to obtain a precursor solution A;

[0037] Then, after the obtained precursor solution A is subjected to a polymerization reaction at a temperature of 25-80℃ for 0.5-72h, it is sequentially subjected to filtration, washing and drying to obtain the precursor A;

[0038] The mass ratio of C3N4, dopamine hydrochloride and base is (0.1-5):(0.1-1):(0.1-1); the solvent A is one or two of methanol, ethanol, isopropanol and water; the base is one or any two of ammonium carbonate, ammonium bicarbonate, ammonia water, diethylamine and tris-hydroxymethyl aminomethane.

[0039] Step two, preparation of precursor B:

[0040] The molybdenum source, the metal source and the precursor A are sequentially added into the solvent B, mixed, heated to 40-90℃ to remove the solvent B, dried, and then the precursor B containing metal ions on the surface is obtained;

[0041] The mass ratio of the molybdenum source, the metal source and the precursor A is (1-10):(0.1-1):(10-100).

[0042] The solvent B is one or two of methanol, ethanol, isopropanol and water; the molybdenum source is any one of ammonium molybdate, sodium molybdate, molybdenum chloride, phosphomolybdate, molybdic acid and molybdenum acetylacetone.

[0043] The metal source is one or two of Fe source, Co source, Ni source and Cu source; the Fe source in the metal source is derived from ferric nitrate or ferric acetate or acetylacetone iron or ferric chloride; the Co source in the metal source is derived from acetylacetone cobalt or cobalt chloride or cobalt nitrate or cobalt acetate; the Ni source in the metal source is derived from acetylacetone nickel or nickel chloride or nickel nitrate or nickel acetate; the Cu source in the metal source is derived from copper chloride or copper nitrate or copper acetate or acetylacetone copper.

[0044] Step three, preparation of non-noble metal molybdenum carbide-based hydrogenation catalyst:

[0045] Under the condition of pure nitrogen or pure argon atmosphere, the precursor B is pyrolyzed, the pyrolysis treatment time is 0.5-6h, the heating rate is 0.5-20℃ / min, until the pyrolysis treatment temperature is heated to 600-1200℃, then cooled, and then taken out when the temperature is cooled to room temperature, thereby obtaining the non-noble metal molybdenum carbide-based hydrogenation catalyst.

[0046] Example 2: the same as example 1, except that the solvent A used in step one is water, and the base is ammonium bicarbonate; and the mass ratio of C3N4, dopamine hydrochloride and base is 1:0.2:0.1; then, polymerization is carried out at 30℃ for 12h;

[0047] In step two, cobalt nitrate is used as the metal source.

[0048] In step three, the pyrolysis treatment time is 1h, and the pyrolysis treatment heating rate is 5℃ / min.

[0049] Example 3: the same as example 1, except that the solvent A in step one is a mixed solution of water and methanol; the base is ammonia water and tris-hydroxymethyl aminomethane; and the polymerization time is 6h at 60℃.

[0050] In step two, acetylacetone molybdenum is used as the molybdenum source or cobalt acetate is used as the metal source.

[0051] And in step three, the pyrolysis treatment temperature is heated to 900℃ and then cooled.

[0052] Example 4: The same as example 1, except that: the solvent A in step one is a mixed solution of water and ethanol; the base is ammonium carbonate and ethylenediamine; and the polymerization time is 12h at 50℃;

[0053] Step two is to use ammonium molybdate as the molybdenum source or iron acetate or nickel nitrate as the metal source;

[0054] The treatment time of pyrolysis treatment in step three is 1h; the heating rate of pyrolysis treatment is 3℃ / min; and the temperature is raised to 800℃ and then lowered.

[0055] Example 5: The same as example 1, except that: the solvent A is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1-1).

[0056] Example 6: The same as example 1, except that: the solvent B is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1-1).

[0057] Example 7: The application also provides a non-noble metal molybdenum carbide-based hydrogenation catalyst prepared by the above method, which is a two-dimensional sheet structure molybdenum carbide catalyst with iron or cobalt or nickel or copper atom doping as the catalytically active component.

[0058] In order to further illustrate the technical effects of the application, the following specific experimental examples are provided:

[0059] Specific experimental example 1: As shown in the following, a preparation method of a non-noble metal single-atom doped molybdenum carbide catalyst, comprising the following steps: Figure 1

[0060] Step 1: 1.0g C3N4 is dispersed in 100mL methanol, and ultrasonic treatment is performed for 20 minutes.

[0061] Step 2: 1.0g dopamine hydrochloride is added to the solution obtained in step 1, and stirring is performed at room temperature for 20 minutes.

[0062] Step 3: 1.33g tris-hydroxymethyl aminomethane is added to the mixed solution in step 2, and then a polymerization reaction is performed at 30℃ for 36h, followed by filtration, washing and drying to obtain a precursor A.

[0063] Step 4: phosphomolybdic acid, iron acetylacetone and the precursor A are sequentially added to ethanol and mixed, and then heating is performed to 60℃ to remove the solvent ethanol, and drying is performed to obtain a precursor B containing metal ions on the surface.

[0064] ​Step 5: The precursor B was taken out after pyrolysis treatment for 2 h, the temperature rising rate was 2 ℃ / min, and the temperature was lowered after the pyrolysis treatment temperature was raised to 700 ℃, and the high-performance non-noble metal molybdenum carbide-based hydrogenation catalyst named Fe-MoC 1-x @CN-700.

[0065] In step 4, cobalt acetylacetonate was used as the metal source. The non-noble metal molybdenum carbide-based catalyst obtained in this experimental example was named Co-MoC 1-x @CN-700.

[0066] Figure 1 The Fe-MoC 1-x @CN-700 catalyst prepared in this experimental example was taken out after pyrolysis treatment for 2 h, the temperature rising rate was 2 ℃ / min, and the temperature was lowered after the pyrolysis treatment temperature was raised to 700 ℃, and the high-performance non-noble metal molybdenum carbide-based hydrogenation catalyst named Fe-MoC

[0067] Specific Experimental Example 2: As shown in Figure 2 , 3 the same as specific experimental example 1, except that:

[0068] In step 4, cobalt acetylacetonate was used as the metal source.

[0069] In step 5, the pyrolysis treatment temperature was 700 ℃.

[0070] The non-noble metal molybdenum carbide-based catalyst obtained in this example was named Co-MoC 1-x @CN-700.

[0071] Figure 2 The Co-MoC 1-x @CN-700 catalyst prepared in this experimental example was taken out after pyrolysis treatment for 2 h, the temperature rising rate was 2 ℃ / min, and the temperature was lowered after the pyrolysis treatment temperature was raised to 700 ℃, and the high-performance non-noble metal molybdenum carbide-based hydrogenation catalyst named Fe-MoC

[0072] Figure 3 The Co-MoC 1-x @CN-700 catalyst prepared in this experimental example was taken out after pyrolysis treatment for 2 h, the temperature rising rate was 2 ℃ / min, and the temperature was lowered after the pyrolysis treatment temperature was raised to 700 ℃, and the high-performance non-noble metal molybdenum carbide-based hydrogenation catalyst named Fe-MoC

[0073] Specific Experimental Example 3: As shown in Figure 4 the same as specific experimental example 1, except that:

[0074] In step 4, cobalt acetylacetonate was used as the metal source.

[0075] In step 5, the temperature of pyrolysis treatment is 600℃.

[0076] The non-noble metal molybdenum carbide-based catalyst obtained in this example is named Co-MoC 1-x @CN-600.

[0077] Figure 4 The Co-MoC prepared in this example is named Co-MoC 1-x @CN-600 catalyst, it can be seen that the characteristic diffraction peaks attributed to Co do not appear in the X-ray diffraction pattern of the Co-doped molybdenum carbide catalyst prepared, indicating that the Co of the catalyst is in a highly dispersed state.

[0078] Specific Experimental Example 4: As shown in Figure 5 the same as Specific Experimental Example 1, except that:

[0079] In step 5, the temperature of pyrolysis treatment is 800℃.

[0080] The non-noble metal molybdenum carbide-based catalyst obtained in this example is named Fe-MoC 1-x @CN-800.

[0081] Figure 5 The Fe-MoC prepared in this example is named Fe-MoC 1-x @CN-800 catalyst, it can be seen that the characteristic diffraction peaks attributed to Fe do not appear in the X-ray diffraction pattern of the Fe-doped molybdenum carbide catalyst prepared, indicating that increasing the pyrolysis treatment temperature to 800℃ does not cause significant agglomeration of Fe in the catalyst.

[0082] Specific Experimental Example 5: The same as Specific Experimental Example 1, except that:

[0083] In step 4, acetyl nickel is used as the metal source.

[0084] In step 5, the temperature of pyrolysis treatment is 800℃.

[0085] The non-noble metal molybdenum carbide-based catalyst obtained in this example is named Ni-MoC 1-x @CN-800.

[0086] Specific Experimental Example 6: The same as Specific Experimental Example 1, except that:

[0087] In step 4, cobalt nitrate is used as the metal source. The non-noble metal molybdenum carbide-based catalyst obtained in this example is named Co-MoC 1-x @CN-700-NO.

[0088] Specific Experimental Example 7: The same as Specific Experimental Example 1, except that:

[0089] In step 4, cobalt chloride is used as the metal source.

[0090] The non-noble metal molybdenum carbide-based catalyst obtained in this experimental example is named Co-MoC 1-x @CN-700-Cl.

[0091] Experimental Example 8: The same as Experimental Example 1, except that:

[0092] In step 4, cobalt acetate is used as the metal source.

[0093] The non-noble metal molybdenum carbide-based catalyst obtained in this experimental example is named Co-MoC 1-x @CN-700-Ac.

[0094] Comparative Experimental Example 1: The same as Experimental Example 1, except that:

[0095] In step 4, only phosphomolybdic acid is added. The prepared catalyst is denoted as MoC 1-x @CN-700.

[0096] Comparative Experimental Example 2: The same as Experimental Example 1, except that:

[0097] In step 4, only iron acetylacetonate is added. The prepared catalyst is denoted as Fe@CN-700.

[0098] Comparative Experimental Example 3: The same as Experimental Example 1, except that:

[0099] In step 4, only cobalt acetylacetonate is added. The prepared catalyst is denoted as Co@CN-700.

[0100] Table 1 is the reaction data of the catalysts prepared in Experimental Example 1, Comparative Experimental Example 1 and Comparative Experimental Example 2 for the selective hydrogenation of m-chloronitrobenzene, and the reaction conditions are as follows: catalyst dosage 20 mg, reactant: 0.5 mmol, solvent: ethanol 5 mL, reaction temperature 80°C, hydrogen pressure 1 MPa, reaction time 20 min.

[0101] Table 1 Different catalysts for selective hydrogenation of p-chloronitrobenzene

[0102]

[0103] The selectivity refers to the selectivity of p-chloroaniline in the product.

[0104] As can be seen from Table 1, compared with the single metal Fe@CN-700 and MoC 1-x @CN-700 catalyst, the Fe-doped Fe-MoC 1-x @CN-700 catalyst exhibits more excellent performance for the selective hydrogenation of m-chloronitrobenzene.

[0105] Table 2 is the reaction data of the catalysts prepared in specific experimental example 2, comparative experimental example 2 and comparative experimental example 3 for selective hydrogenation of p-nitrophenol and quinoline, the reaction conditions are: catalyst dosage 30 mg, reactant: 0.5 mmol, solvent: ethanol 5 mL, the reaction time of p-nitrophenol is 18 h, and the reaction time of quinoline is 12 h.

[0106] Table 2 is the reaction data of the catalysts prepared in specific experimental example 2, comparative experimental example 2 and comparative experimental example 3 for selective hydrogenation of p-nitrophenol and quinoline, the reaction conditions are: catalyst dosage 30 mg, reactant: 0.5 mmol, solvent: ethanol 5 mL, the reaction time of p-nitrophenol is 18 h, and the reaction time of quinoline is 12 h.

[0107]

[0108] The selectivity of p-nitrophenol hydrogenation refers to the selectivity of p-aminophenol in the product, and the selectivity of quinoline hydrogenation refers to the selectivity of 1,2,3,4-tetrahydroquinoline in the product.

[0109] As can be seen from Table 2, compared with single-metal Co@CN-700 and MoC 1-x @CN-700 catalyst, the Co-doped Co-MoC 1-x @CN-700 catalyst exhibits excellent p-nitrophenol selective hydrogenation performance under mild reaction conditions. In addition, compared with single-metal Co@CN-700 and MoC 1-x @CN-700 catalyst, the Co-MoC 1-x @CN-700 catalyst also exhibits excellent quinoline selective hydrogenation performance.

[0110] Taking the cobalt atom-doped molybdenum carbide catalyst as an example, when the type of metal cobalt precursor is changed, the Co-MoC 1-x @CN-700-Ac catalyst prepared by taking cobalt nitrate as the metal source exhibits the optimal catalytic performance in p-nitrophenol hydrogenation and quinoline hydrogenation.

[0111] In order to further embody the universality of the catalysts in the application field of catalytic hydrogenation, the catalysts prepared in specific experimental example 2, comparative experimental example 2 and comparative experimental example 3 are applied to the reaction of preparing imine by catalytic hydrogenation coupling of nitrobenzene and benzaldehyde.

[0112] Table 3 is the reaction results of different catalysts for catalytic hydrogenation coupling of nitrobenzene and benzaldehyde

[0113]

[0114] The conversion rate in the reaction refers to the conversion rate of nitrobenzene, and the selectivity in the reaction refers to the selectivity of benzylidene aniline in the product.

[0115] As shown in Table 3, compared with single-metal Co@CN-700 and MoC 1-xCN-700 catalyst, Co atom doped Co-MoC 1-x The CN-700 catalyst also exhibits excellent catalytic performance in the catalytic hydrogenation coupling of nitrobenzene and benzaldehyde under mild reaction conditions.

[0116] Therefore, the non-noble metal single-atom doped molybdenum carbide catalyst involved in the present application exhibits excellent catalytic performance in various catalytic hydrogenation reactions, that is, has good universality in the field of catalytic hydrogenation.

[0117] The above merely describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A method for preparing a non-noble metal single-atom doped molybdenum carbide catalyst, characterized in that, Includes the following steps: Step 1: Preparation of precursor A: First, C3N4 is dispersed in solvent A and sonicated for 10–120 minutes to obtain a C3N4 mixture with a concentration of 10–100 g / L; then, dopamine hydrochloride is added to the C3N4 mixture, and alkali is added while stirring at room temperature to obtain precursor solution A. Then, the obtained precursor liquid A is subjected to polymerization reaction at a temperature of 25-80℃ for 0.5-72h, and then filtered, washed and dried to obtain precursor A. The mass ratio of C3N4 to dopamine hydrochloride and base is (0.1~5):(0.1~1):(0.1~1); the solvent A is one or two of methanol, ethanol, isopropanol and water. The base is one or any two of the following: ammonium carbonate, ammonium bicarbonate, ammonia, diethylamine, and tris(hydroxymethyl)aminomethane; Step 2, Preparation of Precursor B: Molybdenum source, metal source and precursor A are added to solvent B in sequence and mixed well. The mixture is then heated to 40~90℃ to remove solvent B. After drying, precursor B containing metal ions on its surface is obtained. The mass ratio of molybdenum source, metal source, and precursor A is (1~10):(0.1~1):(10~100). Solvent B is one or two of methanol, ethanol, isopropanol, and water; The molybdenum source can be any one of ammonium molybdate, sodium molybdate, molybdenum chloride, phosphomolybdic acid, molybdic acid, or molybdenum acetylacetonate. The metal source is one or two of Fe, Co, Ni, and Cu sources; Step 3: Preparation of non-noble metal single-atom doped molybdenum carbide catalyst: Precursor B is subjected to pyrolysis under a pure nitrogen or pure argon atmosphere for 0.5 to 6 hours at a heating rate of 0.5 to 20 °C / min until the pyrolysis temperature reaches 600 to 1200 °C. The temperature is then lowered until it reaches room temperature, at which point the precursor is removed to obtain the non-noble metal single-atom doped molybdenum carbide catalyst.

2. The preparation method of the non-noble metal single-atom doped molybdenum carbide catalyst as described in claim 1, characterized in that, The Fe source in the metal source is derived from ferric nitrate, ferric acetate, ferric acetylacetone, or ferric chloride; the Co source in the metal source is derived from cobalt acetylacetone, cobalt chloride, cobalt nitrate, or cobalt acetate; the Ni source in the metal source is derived from nickel acetylacetone, nickel chloride, nickel nitrate, or nickel acetate; and the Cu source in the metal source is derived from copper chloride, copper nitrate, copper acetate, or copper acetylacetone.

3. The method for preparing a non-noble metal single-atom doped molybdenum carbide catalyst as described in claim 1 or 2, characterized in that, Solvent A is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1~1).

4. The method for preparing a non-noble metal single-atom doped molybdenum carbide catalyst as described in claim 1 or 2, characterized in that, The solvent B is any two of methanol, ethanol, isopropanol and water, and the volume ratio of any two is 1:(0.1~1).

5. A non-noble metal single-atom doped molybdenum carbide catalyst prepared by the preparation method described in claim 1 or 2, characterized in that, The catalyst is a two-dimensional sheet-like molybdenum carbide catalyst doped with iron, cobalt, nickel, or copper atoms.

Images