Ni-MoS2atNiS2 catalyst as well as preparation method and application thereof
The in-situ one-step method for preparing NiS2 molecular fence-coated Ni-MoS2 structures solves the problem of oxidation and dissolution of Ni-MoS2 catalysts under alkaline conditions, improves the stability and activity of the catalyst, and promotes the application of water electrolysis for hydrogen production technology.
Patent Information
- Application Number
- CN202511487314.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-01-02
AI Technical Summary
Existing Ni-MoS2 catalysts are easily oxidized and dissolved under alkaline hydrogen evolution conditions, resulting in poor catalytic stability. Furthermore, existing preparation methods are difficult to effectively encapsulate the Ni-MoS2 core, affecting its stability and activity.
A Ni-MoS2 structure (Ni-MoS2@NiS2) with a NiS2 molecular fence was prepared in situ in one step. Ni-MoS2 was confined in the NiS2 molecular fence through a solvothermal method and calcination process to form a core-shell structure, which prevents oxidation and promotes the diffusion of catalytic reaction species.
This significantly improved the stability and activity of the Ni-MoS2 catalyst, optimized the hydrogen production performance of water electrolysis, and provided a new approach for the design of non-precious metal-based water electrolysis catalysts.
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Figure CN121250431A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of water electrolysis for hydrogen production technology, and particularly relates to a Ni-MoS2@NiS2 catalyst, its preparation method, and its application. Background Technology
[0002] Hydrogen, as a clean and sustainable energy carrier, boasts advantages such as high energy density and zero carbon emissions, making it an ideal alternative to traditional fossil fuels. In recent years, with the vigorous development of low-cost renewable energy sources (such as wind and solar power) in my country, hydrogen production through water electrolysis driven by renewable energy represents an important direction for the future development of clean energy technologies. To date, water electrolysis for hydrogen production still faces many challenges, especially the hydrogen evolution reaction (HER) catalyst. Currently, commercially available HER catalysts are still precious metal-based catalysts, represented by Pt. The high price and scarcity of these catalysts severely restrict the widespread application of water electrolysis for hydrogen production. Therefore, developing low-cost, highly active, and stable non-precious metal-based HER catalysts is crucial for promoting the commercial application of water electrolysis for hydrogen production.
[0003] Among numerous non-noble metal-based catalysts, molybdenum disulfide (MoS2) is widely considered an ideal alternative to Pt-based HER catalysts due to its unique electronic structure and physicochemical properties. Since the edge sites of MoS2 were confirmed to possess hydrogen adsorption Gibbs free energy (∆G) similar to that of Pt... H *), and given the typically inert nature of the basal planes, which constitute the majority of the catalyst composition, significant breakthroughs have been achieved in optimizing the HER activity of MoS2-based catalysts. On one hand, researchers have increased the number of edge active sites to enhance HER activity through geometric engineering (such as vertical arrays, porous structures, stepped surface structures, and hollow structures). On the other hand, electronic structure manipulation strategies (such as atomic doping, surface defects, strain, phase transitions, and heterojunctions) have been employed to activate the inert basal planes, thereby improving their intrinsic HER activity. Although optimized MoS2 catalysts exhibit comparable HER catalytic activity to commercial Pt-based catalysts, this high activity is often accompanied by poor stability; that is, the catalytic activity and stability of catalysts typically show an inverse trend. Unfortunately, effective strategies for maintaining the long-term stability of highly active MoS2-based catalysts are still lacking.
[0004] In summary, the following problems exist:
[0005] 1) Highly active Ni-doped MoS2 (Ni-MoS2) is easily oxidized and dissolved under alkaline hydrogen evolution conditions, resulting in poor catalytic stability. Therefore, developing effective strategies to address the activity-stability trade-off faced by Ni-MoS2 catalysts remains a significant challenge.
[0006] 2) Currently widely used multi-step strategies for preparing heterogeneous shell encapsulation structures typically involve directly coating the shell onto a pre-synthesized core substrate, inevitably leading to the oxidation of the Ni-MoS2 core. However, the in-situ one-step preparation of Ni-MoS2 structures coated with NiS2 molecular fences (Ni-MoS2@NiS2) has not yet been reported. Furthermore, the structure-activity relationship between the coated catalyst structure and its HER performance in water electrolysis, as well as the catalytic stability mechanism, lacks in-depth investigation. Summary of the Invention
[0007] To address the aforementioned technical problems, this invention proposes a Ni-MoS2@NiS2 catalyst, its preparation method, and its applications. This invention proposes a "molecular fence" strategy to solve this problem, confining a highly active nickel-doped molybdenum disulfide (Ni-MoS2) catalyst within a molecularly selective NiS2 molecular fence (denoted as Ni-MoS2@NiS2). Electrochemical HER performance testing shows that the constructed NiS2 molecular fence significantly improves the stability of the Ni-MoS2 catalyst and further optimizes its catalytic activity. Therefore, the Ni-MoS2@NiS2 catalyst synthesized in this invention has promising application prospects in the field of water electrolysis for hydrogen production and provides a new approach for the rational design of efficient and stable electrocatalysts.
[0008] To achieve the above objectives, the present invention provides the following technical solution:
[0009] A method for preparing a Ni-MoS2@NiS2 catalyst includes the following steps:
[0010] Molybdenum-nickel alkoxide precursors were prepared by a solvothermal method using molybdenum and nickel sources as raw materials.
[0011] The Ni-MoS2@NiS2 catalyst was prepared by calcining the molybdenum-nickel alkoxide precursor with sublimed sulfur powder under an inert atmosphere.
[0012] Beneficial Effects: This invention employs an in-situ one-step method (calcining the precursor to synthesize Ni-MoS2@NiS2 in one step) to prepare a Ni-MoS2 structure (Ni-MoS2@NiS2) with a NiS2 molecular fence coating. This NiS2 molecular fence can encapsulate the catalyst, preventing the approach of species toxic to the catalyst (Ni-MoS2), while allowing the free diffusion of species related to the catalytic reaction. This results in significantly improved catalytic stability in the alkaline hydrogen evolution reaction and further optimizes the catalytic activity.
[0013] Optionally, the molybdenum source is molybdenum acetylacetonate (MoO2(acac)2), and the nickel source is nickel nitrate hexahydrate;
[0014] Furthermore, the molar ratio of molybdenum in the molybdenum source to nickel in the nickel source is 1:0.5-2. Preferably, it is 1:1, 1:2, or 2:1.
[0015] Optionally, the specific steps of the solvothermal method are as follows:
[0016] The molybdenum source and nickel source are dissolved in a solvent and then reacted at 160-180°C for 6-10 hours.
[0017] Furthermore, the solvent is a mixed solution of glycerol and isopropanol; the volume ratio of the two is 1:3.
[0018] Optionally, the gas used in the inert atmosphere is argon, with a flow rate of 20-40 mL / min.
[0019] Optionally, the mass ratio of the molybdenum nickel alkoxide precursor to sublimed sulfur powder is 1:40-60.
[0020] Optionally, the calcination conditions are as follows: heating to 350-450°C at a heating rate of 2-5°C / min, and then calcining at this temperature for 4-8 hours.
[0021] A Ni-MoS2@NiS2 catalyst was prepared by the above-described preparation method.
[0022] Optionally, the Ni-MoS2@NiS2 catalyst is a Ni-doped MoS2 confined within a NiS2 molecular gate, forming a core-shell structure.
[0023] The above-mentioned Ni-MoS2@NiS2 catalyst is used in the field of hydrogen evolution through water electrolysis.
[0024] Compared with the prior art, the present invention has the following advantages and technical effects:
[0025] The Ni-MoS2@NiS2 water electrolysis HER catalyst synthesized in this invention is obtained through a simple one-step thermal preparation. It exhibits excellent water electrolysis HER activity and stability, and has potential application prospects in the industrial hydrogen production field of water electrolysis. It provides theoretical guidance and technical support for the design, synthesis and practical application of other non-precious metal-based water electrolysis catalysts. Attached Figure Description
[0026] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:
[0027] Figure 1 The XRD and Raman spectra of Ni-MoS2@NiS2, Ni-MoS2 and NiS2 prepared in Example 1 of this invention are shown in (a) and (b) respectively.
[0028] Figure 2 The images shown are (a) low-magnification and (b) high-magnification TEM images of Ni-MoS2@NiS2 prepared in Example 1 of this invention.
[0029] Figure 3 The HAADF-STEM diagram (a) and the corresponding mapping diagram (b) of Ni-MoS2@NiS2 are shown.
[0030] Figure 4 In the middle, (a) is the HER polarization curve of Ni-MoS2@NiS2 and the control sample, (b) is the overpotential, and (c) is the Tafel curve;
[0031] Figure 5 Stability test curves for Ni-MoS2@NiS2 and Ni-MoS2. Detailed Implementation
[0032] 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.
[0033] 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.
[0034] 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.
[0035] 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.
[0036] 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.
[0037] This invention discloses a method for preparing a Ni-MoS2@NiS2 catalyst, comprising the following steps:
[0038] Molybdenum acetylacetonate (MoO2(acac)2) and nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio of 1:1 (here 1:2 or 2:1)) were dissolved in a mixed solution of glycerol and isopropanol with continuous stirring. The resulting mixture was transferred to an 80 mL stainless steel reactor and kept at 160-180 °C for 6-10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the above-prepared molybdenum-nickel alkoxide precursor and sublimed sulfur powder were calcined in a tube furnace at 350-450 °C for 4-8 hours under an ultrapure argon atmosphere to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0039] In some optional embodiments, the molar ratio of molybdenum in molybdenum acetylacetonate to nickel in nickel nitrate hexahydrate is 1:0.5-2, preferably 1:1, 1:2 or 2:1.
[0040] In some alternative embodiments, the volume ratio of glycerol to isopropanol is 1:3.
[0041] In some alternative embodiments, the mass ratio of the molybdenum nickel alkoxide precursor to sublimed sulfur powder is 1:40-60.
[0042] In some alternative embodiments, the argon flow rate is 20-40 mL / min.
[0043] In some alternative embodiments, the heating rate before calcination is 2-5 °C / min.
[0044] Unless otherwise specified, "room temperature" in this invention refers to 20-30℃.
[0045] All raw materials used in this invention were purchased from the market.
[0046] The technical solution of the present invention will be further illustrated by the following embodiments.
[0047] Example 1
[0048] A method for preparing a Ni-MoS2@NiS2 catalyst includes the following steps:
[0049] 0.25 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.25 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio 1:1) were dissolved in a mixture of 10 mL glycerol and 30 mL isopropanol, and the mixture was stirred continuously. The resulting mixture was transferred to an 80 mL stainless steel reactor and kept at 160 °C for 10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the prepared molybdenum-nickel alkoxide precursor was calcined with sublimed sulfur powder (mass ratio 1:50) in a tube furnace at 450 °C (heating rate 5 °C / min) for 4 hours under an ultrapure argon atmosphere (flow rate 40 mL / min) to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0050] Example 2
[0051] The only difference from Example 1 is that the molar ratio of molybdenum in molybdenum acetylacetonate to nickel in nickel nitrate hexahydrate is 1:2. The specific preparation process is as follows:
[0052] 0.25 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.50 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio of 1:2) were dissolved in a mixed solution of 10 mL glycerol and 30 mL isopropanol, and the mixture was stirred continuously. The resulting solution was transferred to an 80 mL stainless steel reactor and kept at 160 °C for 10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the above-prepared molybdenum-nickel alkoxide precursor was calcined with sublimed sulfur powder (mass ratio 1:50) in a tube furnace at 450 °C (heating rate 5 °C / min) for 4 hours under an ultrapure argon atmosphere (flow rate 40 mL / min) to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0053] Example 3
[0054] The only difference from Example 1 is that the molar ratio of molybdenum in molybdenum acetylacetonate to nickel in nickel nitrate hexahydrate is 2:1. The specific preparation process is as follows:
[0055] 0.50 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.25 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio of 2:1) were dissolved in a mixed solution of 10 mL glycerol and 30 mL isopropanol, and the mixture was stirred continuously. The resulting solution was transferred to an 80 mL stainless steel reactor and kept at 160 °C for 10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the above-prepared molybdenum-nickel alkoxide precursor was calcined with sublimed sulfur powder (mass ratio 1:50) in a tube furnace at 450 °C (heating rate 5 °C / min) for 4 hours under an ultrapure argon atmosphere (flow rate 40 mL / min) to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0056] Example 4
[0057] The only difference from Example 1 is that the mass ratio of the molybdenum nickel alkoxide precursor to sublimed sulfur powder is 1:40. The specific preparation process is as follows:
[0058] 0.25 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.25 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio 1:1) were dissolved in a mixed solution of 10 mL glycerol and 30 mL isopropanol, and the mixture was stirred continuously. The resulting solution was transferred to an 80 mL stainless steel reactor and kept at 160 °C for 10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the prepared molybdenum-nickel alkoxide precursor was calcined with sublimed sulfur powder (mass ratio 1:40) in a tube furnace at 450 °C (heating rate 5 °C / min) for 4 hours under an ultrapure argon atmosphere (flow rate 40 mL / min) to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0059] Example 5
[0060] The only difference from Example 1 is that the mass ratio of the molybdenum nickel alkoxide precursor to sublimed sulfur powder is 1:60. The specific preparation process is as follows:
[0061] 0.25 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.25 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molybdenum to nickel molar ratio 1:1) were dissolved in a mixed solution of 10 mL glycerol and 30 mL isopropanol, and the mixture was stirred continuously. The resulting solution was transferred to an 80 mL stainless steel reactor and kept at 160 °C for 10 hours. After cooling to room temperature, the product was separated by centrifugation with ethanol and dried under vacuum at 60 °C for 24 hours. Subsequently, the above-prepared molybdenum-nickel alkoxide precursor was calcined with sublimed sulfur powder (mass ratio 1:60) in a tube furnace at 450 °C (heating rate 5 °C / min) for 4 hours under an ultrapure argon atmosphere (flow rate 40 mL / min) to obtain a Ni-MoS2 structure (Ni-MoS2@NiS2) catalyst with a NiS2 molecular fence coating.
[0062] Comparative Example 1
[0063] NiS2 was selected as the reference sample.
[0064] The only difference between the preparation process of NiS2 and that of Example 1 is that only nickel nitrate hexahydrate was added during the synthesis of the precursor, and molybdenum acetylacetonate was not added.
[0065] Comparative Example 2
[0066] Ni-MoS2 was used as a comparison sample.
[0067] The only difference between the preparation process of Ni-MoS2 and Example 1 is that, in the synthesis of the precursor, the amounts of molybdenum acetylacetonate and nickel nitrate hexahydrate used are: 0.25 mmol of molybdenum acetylacetonate (MoO2(acac)2) and 0.025 mmol of nickel nitrate hexahydrate Ni(NO3)2·6H2O (molar ratio of molybdenum to nickel is 1:0.1).
[0068] Effect verification
[0069] I. The synthesized sample was analyzed using X-ray powder diffraction (XRD) and Raman spectroscopy.
[0070] Figure 1 The images show (a) XRD and (b) Raman spectra of Ni-MoS2@NiS2 prepared in Example 1, Ni-MoS2 prepared in Comparative Example 2, and NiS2 prepared in Comparative Example 1. It can be observed that the diffraction peaks of the Ni-MoS2@NiS2 sample are consistent with the corresponding MoS2 and NiS2 standard cards, indicating the successful synthesis of the Ni-MoS2@NiS2 catalyst. Furthermore, Raman spectroscopy... Figure 1Figure (b) further verifies the composition of Ni-MoS2@NiS2. As can be seen from the figure, at 376 cm⁻¹... -1 and 408 cm -1 The Raman peaks at these locations are attributed to the E1 2g and A 2g of MoS2, respectively. 1g Vibration modes, while 286 and 338 cm -1 The peak at that location belongs to NiS2. The above results indicate that the Ni-MoS2@NiS2 catalyst was successfully synthesized in Example 1. II. The microstructure of the Ni-MoS2@NiS2 sample was tested using field emission transmission electron microscopy (TEM).
[0071] Figure 2 These are (a) low-magnification and (b) high-magnification TEM images of Ni-MoS2@NiS2 prepared in Example 1 of this invention; Figure 2 As shown in Figure 2(a), the core-shell structure of Ni-MoS2@NiS2 nanospheres can be observed. Moreover, the high-resolution transmission electron microscopy (HR-TEM) image recorded on the shell shows clear lattice fringes with a spacing of 0.28 nm, which belong to the 200 crystal plane of NiS2, indicating that the shell of the nanospheres is composed of NiS2 (Figure 2(b)).
[0072] Figure 3 The images shown are HAADF-STEM images (a) and corresponding mapping images (b) of Ni-MoS2@NiS2 prepared in Example 1. The high-angle annular dark-field scanning transmission electron microscope (HAADF-STEM) images further reveal that Ni-MoS2@NiS2 exhibits a core-shell structure. Figure 3 In (a)), the elemental mapping spectrum shows that Mo is mainly distributed inside the nanospheres, while Ni is distributed on the outer shell of the nanospheres. Figure 3 (b)). These results indicate that MoS2 species are confined in situ within the NiS2 shell.
[0073] III. The hydrogen evolution reaction (HER) performance of Ni-MoS2@NiS2 and the control sample was tested in 1 M KOH solution using a standard three-electrode system.
[0074] Figure 4 In the middle section, (a) is the HER polarization curve of Ni-MoS2@NiS2 prepared in Example 1 and the comparative sample, (b) is the overpotential, and (c) is the Tafel curve;
[0075] Figure 5 The stability test curves of Ni-MoS2@NiS2 and Ni-MoS2 prepared in Example 1 are shown.
[0076] Depend on Figure 4 As shown in (a) and (b), at 10 and 100 mA cm -2 At the specified current densities, the overpotentials of Ni-MoS2@NiS2 (56 and 138 mV) are close to those of commercially available noble metal Pt / C (39 and 104 mV), and significantly lower than those of Ni-MoS2 (98 and 205 mV) and NiS2 (245 and 375 mV) comparison samples, indicating that the Ni-MoS2@NiS2 catalyst possesses superior performance. Furthermore, compared to Ni-MoS2 and NiS2, Ni-MoS2@NiS2 exhibits a lower Tafel slope, suggesting faster HER reaction kinetics.
[0077] Furthermore, the electrocatalytic stability of both Ni-MoS2@NiS2 and Ni-MoS2 catalysts was tested at -0.15 V. Figure 5 The chronoamperometry curves show that the current density of Ni-MoS2 gradually decreases as the catalytic reaction proceeds, indicating its poor stability. In stark contrast, due to the protection of the NiS2 molecular barrier, the Ni-MoS2@NiS2 catalyst maintained a stable current density without significant fluctuations during the 240-hour test period. In conclusion, the presence of the NiS2 barrier layer significantly improves the HER activity and stability of the Ni-MoS2 catalyst, making it a promising candidate for hydrogen production through water electrolysis.
[0078] The above are merely preferred embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.
Claims
1. A preparation method of a Ni-MoS2@NiS2 catalyst, characterized in that, The method comprises the following steps: A molybdenum-nickel alcoholate precursor is prepared by using a molybdenum source and a nickel source as raw materials through a solvothermal method; The molybdenum-nickel alcoholate precursor is calcined with sulfur powder under an inert atmosphere to obtain the Ni-MoS2@NiS2 catalyst.
2. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 1, characterized in that, The molybdenum source is molybdenum acetylacetonate, and the nickel source is nickel nitrate hexahydrate.
3. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 2, characterized in that, The molar ratio of molybdenum in the molybdenum source to nickel in the nickel source is 1:0.5-2.
4. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 1, characterized in that, The solvothermal method comprises the following steps: The molybdenum source and the nickel source are dissolved in a solvent, and then reacted at 160-180℃ for 6-10 hours.
5. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 4, characterized in that, The solvent is a mixed solution of glycerol and isopropyl alcohol, and the volume ratio of glycerol to isopropyl alcohol is 1:
3.
6. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 1, characterized in that, The mass ratio of the molybdenum-nickel alcoholate precursor to sulfur powder is 1:40-60.
7. The preparation method of the Ni-MoS2@NiS2 catalyst according to claim 1, characterized in that, The calcination condition is as follows: the temperature is raised to 350-450℃ at a temperature raising rate of 2-5℃ / min, and then calcined at this temperature for 4-8 hours.
8. A Ni-MoS2@NiS2catalyst characterized by, The Ni-MoS2@NiS2 catalyst is prepared by the preparation method of any one of claims 1-7. 9.The Ni-MoS 2 @ NiS 2 catalyst of claim 8, wherein, The Ni-MoS2@NiS2 catalyst is a core-shell structure in which Ni-doped MoS2 is confined in a NiS2 molecular grid.
10. Application of the Ni-MoS2@NiS2 catalyst of claim 8 in the field of water electrolysis hydrogen evolution.