A p-nimo4@mesh-ni2p core-shell structure catalyst, a preparation method and application thereof

Abstract

The application discloses a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst and a preparation method and application thereof. The preparation method of the catalyst comprises the following steps: step 1, cleaning treatment is performed on a nickel substrate; step 2, a precursor NiMoO4 is synthesized on the nickel substrate through a hydrothermal method; step 3, the NiMoO4 is converted into a precursor NiMoO4 / Ni(OH)2 through a secondary hydrothermal method; and step 4, a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst is prepared through phosphorization of the NiMoO4 / Ni(OH)2. The core of the catalyst is a phosphorus-doped NiMoO4 rod-shaped array, and the shell is a fishing net-shaped Ni2P layer. The catalyst exhibits excellent performance in a hydrogen evolution reaction, has high activity and stability, and is suitable for clean hydrogen energy production.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalysts, specifically relating to a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst, its preparation method, and its application. Background Technology

[0002] Electrocatalytic water splitting is a promising clean hydrogen production method, with the hydrogen evolution reaction (HER) as the core process, requiring catalysts with high activity, excellent stability, and cost-effectiveness. While noble metal catalysts (such as Pt) perform well in HER, their high cost limits their large-scale application. Non-noble metal catalysts based on transition metals have become a research focus due to their significant cost reduction advantages. Although various non-noble metal electrocatalysts have been proposed in recent years to improve water splitting efficiency, their performance still lags behind noble metal catalysts, especially in electrocatalytic activity and long-term stability, limiting their widespread application. Firstly, many catalysts suffer from inadequate structural design, resulting in insufficient exposure of active sites and thus limiting their catalytic activity. This structural deficiency prevents the catalysts from fully realizing their potential in practical applications. Secondly, the regulation of electronic structure is one of the key factors affecting catalytic performance; many catalysts exhibit slow HER kinetics due to ineffective optimization of their internal electronic structure. In addition, many powdered catalysts are currently connected to the electrodes using binders, which reduces the conductivity of the catalyst and thus affects its electrochemical performance. Furthermore, the binder may decompose or fall off during long-term use, resulting in a reduction in the active surface area of ​​the catalyst and thus reducing catalytic efficiency. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst, its preparation method, and its applications. It aims to solve problems in existing technologies such as insufficient active area, inadequate electronic structure regulation, and poor conductivity and stability due to the use of binders. Through this invention, the electrochemical activity, conductivity, and long-term stability of the catalyst are significantly improved, exhibiting excellent performance and sustained stability in the hydrogen evolution reaction.

[0004] To achieve the above objectives, this invention provides a method for preparing a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst, comprising the following steps:

[0005] Step 1, Nickel substrate treatment: Place the nickel substrate (2 cm × 5 cm) in 3M hydrochloric acid for ultrasonic cleaning for 5 minutes to remove the surface oxide layer and oil stains; then clean it 3 times alternately with ethanol and deionized water, and finally let it air dry at room temperature.

[0006] The purpose of this step is to provide a clean substrate for subsequent catalyst growth, ensuring good adhesion and uniformity of the catalyst.

[0007] Step 2, Preparation of precursor NiMoO4: Nickel salt and ammonium molybdate ((NH4)6Mo7O) are mixed. 24 Dissolve 4H₂O in 80 mL of deionized water and stir until the solution is clear. Transfer the solution to a 100 mL Teflon-lined autoclave, place the nickel substrate treated in step 1 vertically, and carry out a hydrothermal reaction. After the reaction is complete, cool to room temperature, remove the nickel substrate loaded with the yellow precipitate, wash it successively with deionized water and ethanol, and dry it in a 60 °C oven to obtain the precursor nickel molybdate (NiMoO₄).

[0008] This step forms a rod-shaped array structure with a large specific surface area on a nickel substrate through a hydrothermal reaction, which helps to increase the loading of subsequent active materials and serves as a fast electron transfer channel for the hydrogen evolution reaction process.

[0009] Step 3: Preparation of the precursor NiMoO4 / Ni(OH)2: Nickel salt, ammonium fluoride (NH4F), and urea (CO(NH2)2) were dissolved in 60 mL of deionized water and stirred until the solution was clear. The nickel substrate loaded with NiMoO4 obtained in Step 2 was immersed in the solution and transferred to a 100 mL Teflon-lined autoclave for hydrothermal reaction. After the hydrothermal reaction was completed, the substrate was cooled to room temperature, removed, washed successively with deionized water and ethanol, and dried in a 60 °C oven to obtain the precursor NiMoO4 / Ni(OH)2.

[0010] This step provides a precursor for the subsequent phosphating process by depositing Ni(OH)2 on a NiMoO4 rod array.

[0011] Step 4, Preparation of P-NiMoO4@Mesh-Ni2P: The precursor NiMoO4 / Ni(OH)2 obtained in step 3 and sodium hypophosphite (Na2H2PO2·H2O) were placed in a tube furnace and calcined under an argon atmosphere to finally form the P-NiMoO4@Mesh-Ni2P core-shell structure catalyst.

[0012] Furthermore, the nickel salt used in step 1 can be one or more of nickel nitrate, nickel sulfate, or nickel chloride.

[0013] Furthermore, the concentration of nickel ions in step 2 is 0.01~0.2 mol·L⁻¹. -1 The molar ratio of nickel to molybdenum is 1:0.5~3.

[0014] Furthermore, in step 2, the hydrothermal reaction temperature is 100~160 ℃ and the time is 4~14 h.

[0015] Furthermore, the concentration of nickel ions in step 3 is 0.01~0.1 mol·L⁻¹. -1 The concentration of ammonium fluoride is 0.05~0.5 mol·L⁻¹. -1 The concentration of urea is 0.1~1.0 mol·L⁻¹. -1 .

[0016] Furthermore, the temperature of the hydrothermal reaction in step 3 is 90~150 ℃.

[0017] Furthermore, in step 3, the hydrothermal reaction time is 3~16 h. If the time is too short, the precursor NiMoO4 / Ni(OH)2 cannot be obtained; if the time is too long, the Ni(OH)2 coating layer is too thick, which hinders the exposure of the internal NiMoO4 structure.

[0018] Furthermore, the phosphating temperature in step 4 is 320~380 ℃, the calcination time is 2~6 h, and the heating rate is 2~10 ℃ min. -1 If the temperature is too low, Ni(OH)2 in the precursor cannot be converted into nickel phosphide (Ni2P); if the temperature is too high, the Ni2P structure collapses.

[0019] Furthermore, in step 4, the ratio of the area of ​​the nickel substrate to the amount of sodium hypophosphite is 1 cm². 2 : 0.05~2g.

[0020] On the other hand, this invention also provides a P-NiMoO4@Mesh-Ni2P core-shell structured catalyst prepared by the above method. This catalyst exhibits a unique core-shell structure, with a core consisting of a phosphorus-doped nickel molybdate (P-NiMoO4) rod-like array structure and a shell consisting of a mesh-like Ni2P layer (Mesh-Ni2P) coating the top of the P-NiMoO4. The Mesh-Ni2P provides abundant active sites, while the P-NiMoO4 core provides a rapid electron transfer channel. Furthermore, the interaction between the core P-NiMoO4 and the shell Mesh-Ni2P modulates the electronic structure, optimizes the adsorption energy of the HER intermediate, and thus significantly improves the catalytic performance.

[0021] In another aspect, this invention provides the application of P-NiMoO4@Mesh-Ni2P core-shell structure catalysts in the hydrogen evolution reaction.

[0022] The present invention has the following beneficial effects:

[0023] (1) Structural optimization: The P-NiMoO4@Mesh-Ni2P core-shell structure catalyst significantly improved the activity of the hydrogen evolution reaction through the synergistic effect of the core and shell. The rod-shaped array structure increased the specific surface area and exposed more active sites.

[0024] (2) The catalyst prepared by the method of the present invention can withstand a current density of 10 mA·cm⁻¹. -2 At this current density, it exhibits a low hydrogen evolution overpotential of only 56 mV and can operate stably for 100 hours, demonstrating excellent stability.

[0025] (3) A binder-free self-supporting preparation method is adopted, which allows the catalyst to grow directly on the nickel substrate, thereby possessing excellent conductivity and ensuring efficient electrocatalytic performance.

[0026] (4) The method of the present invention uses low-cost non-precious metal raw materials, which significantly reduces the production cost of catalysts, has good economic benefits, and has the potential for large-scale production. Attached Figure Description

[0027] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 A scanning electron microscope image of the precursor NiMoO4 prepared in Example 1 of this invention;

[0029] Figure 2 This is a scanning electron microscope image of the precursor NiMoO4 / Ni(OH)2 prepared in Example 1 of the present invention;

[0030] Figure 3 This is a scanning electron microscope image of P-NiMoO4@Mesh-Ni2P prepared in Example 1 of the present invention;

[0031] Figure 4 The X-ray powder diffraction pattern of P-NiMoO4@Mesh-Ni2P prepared in Example 1 of this invention;

[0032] Figure 5 The HER performance diagram of P-NiMoO4@Mesh-Ni2P prepared in Example 1 of this invention;

[0033] Figure 6 This is a HER stability test diagram of P-NiMoO4@Mesh-Ni2P prepared in Example 1 of the present invention;

[0034] Figure 7 This is a comparison diagram of the electroactive areas of the catalysts prepared in Example 1, Comparative Example 1, and Comparative Example 2 of the present invention. Detailed Implementation

[0035] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as a limitation of the present invention, but rather as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0036] It should be understood that the terminology used in this invention is merely for describing particular embodiments and is not intended to limit the invention. Furthermore, with respect to numerical ranges in this invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or intermediate value within a stated range, and any other stated value or intermediate value within said range, is also included in this invention. The upper and lower limits of these smaller ranges may be independently included or excluded from the range.

[0037] Unless otherwise stated, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. While only preferred methods and materials have been described herein, any methods and materials similar or equivalent to those described herein may be used in the implementation or testing of this invention. All references to this specification are incorporated by way of citation to disclose and describe methods and / or materials associated with those references. In the event of any conflict with any incorporated reference, the content of this specification shall prevail.

[0038] Various modifications and variations can be made to the specific embodiments described in this specification without departing from the scope or spirit of the invention, as will be apparent to those skilled in the art. Other embodiments derived from this specification will also be apparent to those skilled in the art. This specification and embodiments are merely exemplary.

[0039] The terms “include,” “including,” “have,” “contain,” etc., used in this article are all open-ended terms, meaning that they include but are not limited to.

[0040] Example 1

[0041] Step 1, Nickel substrate treatment: Immerse the nickel substrate (2 cm × 5 cm) in 3 M hydrochloric acid and ultrasonically clean for 5 minutes to remove the surface oxide layer and oil stains. Then clean it three times alternately with ethanol and deionized water, and finally air dry at room temperature.

[0042] Step 2, Preparation of the precursor NiMoO4: 0.8 mmol of ammonium molybdate ((NH4)6Mo7O) was added. 24 3.2 mmol of nickel nitrate (Ni(NO3)2·6H2O) and 4H2O were dissolved in 80 mL of deionized water and stirred until the solution was clear. The concentration of nickel ions in the solution was 0.04 mol·L⁻¹. -1The molar ratio of nickel to molybdenum was 1:1.75. The solution was transferred to a 100 mL Teflon-lined autoclave, and the nickel substrate treated in step 1 was placed vertically and subjected to a hydrothermal reaction at 150°C for 5 hours. After cooling to room temperature, it was removed, washed with deionized water and ethanol, and dried in an oven at 60°C to obtain the precursor NiMoO4.

[0043] Step 3: Preparation of the precursor NiMoO4 / Ni(OH)2: Dissolve 2 mmol nickel nitrate, 10 mmol ammonium fluoride (NH4F), and 20 mmol urea (CO(NH2)2) in 60 mL of deionized water and stir until the solution is clear. The concentration of nickel ions in the solution is 0.033 mol·L⁻¹. -1 The concentration of ammonium fluoride was 0.167 mol·L⁻¹. -1 The concentration of urea is 0.333 mol·L⁻¹. -1 The nickel substrate loaded with NiMoO4 obtained in step 2 was immersed in the solution and transferred to a 100 mL Teflon-lined autoclave for hydrothermal reaction at 120°C for 6 hours. After cooling to room temperature, it was removed, washed with deionized water and ethanol, and dried in a 60°C oven to obtain the precursor NiMoO4 / Ni(OH)2.

[0044] Step 4, Preparation of P-NiMoO4@Mesh-Ni2P: The precursor NiMoO4 / Ni(OH)2 obtained in Step 3 is mixed with 1.0 g of sodium hypophosphite (the ratio is 1 cm⁻¹). 2 Mix 0.1 g of the mixture and place it in a tube furnace for phosphating. The phosphating temperature is 350°C, the calcination time is 2 hours, and the heating rate is 5°C / min. -1 A P-NiMoO4@Mesh-Ni2P core-shell structured catalyst was obtained.

[0045] Example 2

[0046] Step 1, Nickel substrate treatment: Immerse the nickel substrate (2 cm × 5 cm) in 3 M hydrochloric acid and ultrasonically clean for 5 minutes to remove the surface oxide layer and oil stains. Then clean it three times alternately with ethanol and deionized water, and finally air dry at room temperature.

[0047] Step 2, Preparation of the precursor NiMoO4: 0.8 mmol of ammonium molybdate ((NH4)6Mo7O) was added. 24 3.2 mmol of nickel nitrate (Ni(NO3)2·6H2O) and 4H2O were dissolved in 80 mL of deionized water and stirred until the solution was clear. The concentration of nickel ions in the solution was 0.04 mol·L⁻¹. -1The molar ratio of nickel to molybdenum was 1:1.75. The solution was transferred to a 100 mL Teflon-lined autoclave, and the nickel substrate treated in step 1 was placed vertically and subjected to a hydrothermal reaction at 150°C for 5 hours. After cooling to room temperature, it was removed, washed with deionized water and ethanol, and dried in an oven at 60°C to obtain the precursor NiMoO4.

[0048] Step 3: Preparation of the precursor NiMoO4 / Ni(OH)2: Dissolve 1 mmol nickel nitrate, 5 mmol ammonium fluoride (NH4F), and 10 mmol urea (CO(NH2)2) in 60 mL of deionized water and stir until the solution is clear. The concentration of nickel ions in the solution is 0.017 mol·L⁻¹. -1 The concentration of ammonium fluoride is 0.085 mol·L⁻¹. -1 The concentration of urea is 0.167 mol·L⁻¹. -1 The nickel substrate loaded with NiMoO4 obtained in step 2 was immersed in the solution and transferred to a 100 mL Teflon-lined autoclave for hydrothermal reaction at 150°C for 4 hours. After cooling to room temperature, it was removed, washed with deionized water and ethanol, and dried in a 60°C oven to obtain the precursor NiMoO4 / Ni(OH)2.

[0049] Step 4, Preparation of P-NiMoO4@Mesh-Ni2P: The precursor NiMoO4 / Ni(OH)2 obtained in Step 3 was mixed with 2.0 g of sodium hypophosphite (the ratio was 1 cm⁻¹). 2 Mix 0.2 g of the ingredients and place them in a tube furnace for phosphating. The phosphating temperature is 350°C, the calcination time is 2 hours, and the heating rate is 5°C / min. -1 A P-NiMoO4@Mesh-Ni2P core-shell structured catalyst was obtained.

[0050] Example 3

[0051] Step 1, Nickel substrate treatment: Immerse the nickel substrate (2 cm × 5 cm) in 3 M hydrochloric acid and ultrasonically clean for 5 minutes to remove the surface oxide layer and oil stains. Then clean it three times alternately with ethanol and deionized water, and finally air dry at room temperature.

[0052] Step 2, Preparation of the precursor NiMoO4: 0.6 mmol of ammonium molybdate ((NH4)6Mo7O) was added. 24 2.4 mmol of nickel nitrate (Ni(NO3)2·6H2O) and 2.4 mmol of nickel nitrate (Ni(NO3)2·6H2O) were dissolved in 80 mL of deionized water and stirred until the solution was clear. The concentration of nickel ions in the solution was 0.03 mol·L⁻¹. -1The molar ratio of nickel to molybdenum was 1:1.75. The solution was transferred to a 100 mL Teflon-lined autoclave, and the nickel substrate treated in step 1 was placed vertically and subjected to a hydrothermal reaction at 120°C for 12 hours. After cooling to room temperature, the substrate was removed, washed with deionized water and ethanol, and dried in an oven at 60°C to obtain the NiMoO4 precursor.

[0053] Step 3: Preparation of the precursor NiMoO4 / Ni(OH)2: Dissolve 1 mmol nickel nitrate, 5 mmol ammonium fluoride (NH4F), and 10 mmol urea (CO(NH2)2) in 60 mL of deionized water and stir until the solution is clear. The concentration of nickel ions in the solution is 0.017 mol / L. -1 The concentration of ammonium fluoride is 0.085 mol·L⁻¹. -1 The concentration of urea is 0.167 mol·L⁻¹. -1 The nickel substrate loaded with NiMoO4 obtained in step 2 was immersed in the solution and transferred to a 100 mL Teflon-lined autoclave for hydrothermal reaction at 120°C for 12 hours. After cooling to room temperature, it was removed, washed with deionized water and ethanol, and dried in a 60°C oven to obtain the precursor NiMoO4 / Ni(OH)2.

[0054] Step 4, Preparation of P-NiMoO4@Mesh-Ni2P: The precursor NiMoO4 / Ni(OH)2 obtained in Step 3 is mixed with 1.0 g of sodium hypophosphite (the ratio is 1 cm⁻¹). 2 Mix 0.1 g of the mixture and place it in a tube furnace for phosphating. The phosphating temperature is 350°C, the calcination time is 2 hours, and the heating rate is 5°C / min. -1 A P-NiMoO4@Mesh-Ni2P core-shell structured catalyst was obtained.

[0055] Physical characterization: The P-NiMoO4@Mesh-Ni2P core-shell structure catalyst and its precursor obtained in Example 1 were physically characterized, and the results are as follows:

[0056] Scanning electron microscope image of the precursor NiMoO4 ( Figure 1 The image shows a smooth micro / nanorrod array structure; a scanning electron microscope image of the precursor NiMoO4 / Ni(OH)2. Figure 2 The image shows that Ni(OH)₂ exhibits an interwoven nanosheet structure, coating the top of the NiMoO₄ micro / nanoring array structure. (SEM image of P-NiMoO₄@Mesh-Ni₂P) Figure 3It exhibits a unique core-shell structure, with a core consisting of a phosphorus-doped nickel molybdate (P-NiMoO4) rod-like array; the shell is a mesh-like Ni2P layer covering the top of the P-NiMoO4. X-ray diffraction patterns show ( Figure 4 The main components include Ni2P (PDF# 03-0953) and NiMoO4 (PDF#45-0142). During the phosphating process, P is also doped into the core NiMoO4.

[0057] Application in the hydrogen evolution reaction:

[0058] The P-NiMoO4@Mesh-Ni2P catalyst prepared in Example 1 was tested for activity and stability in the hydrogen evolution reaction.

[0059] (1) Activity test: The HER catalytic performance of P-NiMoO4@Mesh-Ni2P was evaluated using a standard three-electrode system in 1.0 M KOH solution. The polarization curves obtained by linear sweep voltammetry (LSV) were used to assess the catalytic activity. Figure 5 The results show that this catalyst requires only 49 mV overpotential to drive 10 mA·cm² in the hydrogen evolution reaction. -2 The current density is close to that of the Pt / C catalyst (25 mV). Furthermore, the nickel substrate (Ni Foam) exhibits poor activity at 10 mA·cm⁻¹. -2 At the current density, the overpotential was 267 mV, indicating that the catalytic activity of the self-supporting electrode used in the test came from the P-NiMoO4@Mesh-Ni2P catalyst supported on the nickel substrate surface.

[0060] (2) Stability test: at -100 mAcm -2 At the specified current density, the catalyst operated stably for 100 hours without significant activity degradation. Figure 6 ).

[0061] Comparative Example 1

[0062] The difference from Example 1 is that in step 3, a bare nickel substrate was used instead of a nickel substrate loaded with the precursor NiMoO4 for the second hydrothermal reaction, while the other steps remained the same, thereby preparing a catalyst with Ni2P grown on a nickel substrate.

[0063] Electrochemical activity tests on the Ni2P catalyst showed that, in the hydrogen evolution reaction, · [the desired effect] was achieved by [a specific method / mechanism] to obtain 10 mA·cm [a specific reaction / mechanism]. -2 The current density requires an overpotential of 176 mV. Figure 5 Its activity is significantly lower than that of the P-NiMoO4@Mesh-Ni2P catalyst in Example 1 (49 mV).

[0064] Comparative Example 2

[0065] The difference from Example 1 is that the second hydrothermal reaction in step 3 is not performed. The nickel substrate supported on NiMoO4 prepared in step 2 is used directly for phosphating to obtain a phosphorus-doped nickel molybdate catalyst (P-NiMoO4) grown on the nickel substrate.

[0066] Electrochemical activity tests on the P-NiMoO4 catalyst showed that at 10 mA·cm⁻¹, -2 When the hydrogen evolution reaction is carried out at a current density of , an overpotential of 201 mV needs to be applied ( Figure 5 Its activity is much lower than that of the P-NiMoO4@Mesh-Ni2P catalyst (49 mV) prepared in Example 1.

[0067] Furthermore, as Figure 7 As shown, compared with the catalysts of Comparative Examples 1 and 2, the P-NiMoO4@Mesh-Ni2P catalyst prepared in Example 1 has a lower Tafel slope (47.8 mV dec). -1 () Figure 7 (a) indicates that it has faster hydrogen evolution reaction kinetics. Simultaneously, the catalyst also exhibits a larger active surface area (254.4 mF cm⁻¹). -2 () Figure 7 b). These results demonstrate that the P-NiMoO4@Mesh-Ni2P core-shell structure is an electrocatalyst for hydrogen evolution reaction exhibiting excellent performance.

[0068] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for preparing a P-NiMoO 4 @Mesh-Ni 2 P core-shell structure catalyst, characterized in that, The method comprises the following steps: Step 1, nickel substrate treatment: the nickel substrate is placed in 3M hydrochloric acid for ultrasonic cleaning for 5 minutes to remove the surface oxide layer and oil stains; then the nickel substrate is cleaned with ethanol and deionized water alternately for 3 times, and is dried at room temperature; Step 2, preparation of precursor NiMoO4: nickel salt and ammonium molybdate are dissolved in 80 mL deionized water, and the solution is stirred until it is clear; the solution is transferred to a 100 mL Teflon-lined autoclave, the treated nickel substrate in step 1 is placed vertically, and a hydrothermal reaction is carried out; after the reaction is completed, the nickel substrate is cooled to room temperature, cleaned with deionized water and ethanol, and dried in a 60°C oven to obtain the precursor NiMoO4; Step 3, preparation of precursor NiMoO4 / Ni(OH)2: nickel salt, ammonium fluoride and urea are dissolved in 60 mL deionized water, and the solution is stirred until it is clear; the nickel substrate loaded with NiMoO4 obtained in step 2 is immersed in the solution, and a hydrothermal reaction is carried out in a 100 mL Teflon-lined autoclave; after the reaction is completed, the nickel substrate is cooled to room temperature, cleaned with deionized water and ethanol, and dried in a 60°C oven to obtain the precursor NiMoO4 / Ni(OH)2; Step 4: preparation of P-NiMoO4@Mesh-Ni2P: the nickel substrate loaded with the precursor NiMoO4 / Ni(OH)2 in step 3 and sodium hypophosphite are simultaneously placed in a tube furnace for phosphating treatment to obtain a P-NiMoO4@Mesh-Ni2P core-shell structure catalyst; The core is a phosphorus-doped nickel molybdate (P-NiMoO4) rod array structure, and the shell is a fishing net-shaped nickel phosphide layer (Mesh-Ni2P) which is coated on the top of the rod array structure.

2. The production method according to claim 1, characterized by, The concentration of the nickel salt in step 2 is 0.01-0.2 mol / L -1 The molar ratio of nickel to molybdenum is 1:0.5-3.

3. The production method according to claim 1, characterized by, The hydrothermal reaction temperature in step 2 is 100-160°C, and the time is 4-14 h.

4. The production method according to claim 1, characterized by, The concentration of the nickel salt in step 3 is 0.01-0.1 mol·L -1 The concentration of the ammonium fluoride is 0.05-0.5 mol·L -1 The concentration of the urea is 0.1-1.0 mol·L -1 .

5. The production method according to claim 1, characterized by, The hydrothermal reaction temperature in step 3 is 90-150°C, and the time is 3-16 h.

6. The production method according to claim 1, characterized by, The ratio of the area of the nickel substrate and the amount of sodium hypophosphite used in Step 4 is 1 cm 2 : 0.05 ~ 2 g.

7. The production method according to claim 1, characterized by, The phosphating temperature in Step 4 is 320-380 °C, the calcination time is 2-6 h, and the heating rate is 2-10 °C min -1 .

8. The P-NiMoO4@Mesh-Ni2P core-shell structure catalyst prepared by the preparation method of any one of claims 1-7.

9. Application of the P-NiMoO4@Mesh-Ni2P core-shell structure catalyst of claim 8 in a hydrogen evolution reaction.

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