Heterostructure electrocatalyst for ruthenium monatomic synergistic sulfur vacancy regulation as well as preparation method and application of heterostructure electrocatalyst

Abstract

The invention discloses a heterostructure electrocatalyst with ruthenium monatomic synergistic sulfur vacancy regulation and control as well as a preparation method and application of the heterostructure electrocatalyst. The heterostructure electrocatalyst is a Ru-VS-MoS2 / NixSy (at) CC self-supporting electrode, cC represents carbon cloth, and the electrocatalyst takes a carbon cloth substrate as a conductive self-supporting framework and has a three-dimensional fiber structure; moS2 / NixSy grows on the surface of the carbon cloth in situ to form a MoS2 / NixSy heterostructure, and MoS2 is rich in sulfur vacancies VS and defects so as to enhance the catalytic activity of a basal plane; the MoS2 / Ni < x > S < y > heterostructure is in a nano sheet shape; ruthenium single atoms are anchored at sulfur vacancies or defect sites of MoS2 and are used as active catalytic components. According to the invention, atomic dispersion of active sites and electronic structure optimization are accurately controlled, the use amount of noble metal is greatly reduced while excellent catalytic activity is maintained, the application of an industrial electrolytic cell is realized in combination with a preparation process capable of being amplified, and a breakthrough solution is provided for commercial application of a water electrolysis hydrogen production technology.

Description

Technical Field

[0001] This application belongs to the field of hydrogen production by water electrolysis, and relates to a heterostructure electrocatalyst with ruthenium single atom synergistic sulfur vacancy regulation, its preparation method and application. Background Technology

[0002] Hydrogen energy, as a clean and efficient renewable energy source, is considered an important component of the future energy system. Hydrogen production through water electrolysis can achieve zero carbon emissions and produce high-purity hydrogen, fully aligning with the goal of carbon neutrality. Among various water electrolysis technologies, anion exchange membrane (AEM) electrolysis is becoming the most promising hydrogen production technology due to its combination of the high efficiency of proton exchange membrane (PEM) electrolysis and the low cost of traditional alkaline electrolysis. Particularly in the field of hydrogen evolution reaction (HER) under alkaline conditions, AEM technology demonstrates broad prospects for industrial application due to its low equipment cost and mature process. Platinum-based catalysts exhibit excellent HER activity, but their high cost and scarcity severely restrict their large-scale application. Therefore, the core bottleneck of this technology lies in the development of efficient and low-cost electrocatalysts.

[0003] In recent years, transition metal-based electrocatalysts, especially molybdenum-based materials, have attracted much attention due to their unique electronic structure and platinum-like hydrogen adsorption properties. Among them, layered molybdenum disulfide (MoS2) stands out for its high hydrogen adsorption free energy (ΔG) at its edge sites. H* With a potential energy level close to platinum (≈0.08 eV), MoS2 has become a research hotspot. However, MoS2 lacks basal active sites (ΔG). H* The low temperature (≈2eV) limits its overall catalytic performance, especially in alkaline media where the slow dissociation kinetics of water molecules are more pronounced, further restricting its hydrogen evolution performance.

[0004] For example, Li et al. constructed a single-atom Ru-modified MoS2 / MoP heterostructure on carbon cloth using electrostatic deposition, which significantly improved the basic HER activity; Xu et al. designed Ru nanoparticles anchored in a MoS2 / carbon fiber paper composite substrate, exhibiting highly efficient catalytic properties through multi-interface synergistic effects; and Jian's research group prepared 1T / 2HMoS2 / Ti3C2T using an ultrasonic-mechanical stirring method. xHeterogeneous structures exhibit excellent catalytic activity in both acidic and alkaline media. For example, patent CN118727040A discloses a 1T-MoS2 supported ruthenium single-atom lattice catalyst and its preparation method. The 1T-MoS2 supported Ru single-atom lattice catalyst comprises: a substrate, a metal 1T-MoS2 layer coated on the substrate, and Ru single-atom lattice supported on the surface of the metal 1T-MoS2 layer. The mass content of Mo atoms is 6.5–8.5 wt.%, and the mass content of Ru atoms is 0.04–0.11 wt.%, relative to 100 g of the 1T-MoS2 supported Ru single-atom lattice catalyst. Nevertheless, existing technologies still suffer from problems such as complex preparation processes, high costs, and insufficient catalyst activity and stability.

[0005] To address this challenge, researchers have proposed various modification strategies, including defect engineering, heterostructure construction, and single-atom doping. However, in terms of industrial applications, existing electrocatalysts still heavily rely on the precious metal platinum, making it difficult to simultaneously meet the requirements of high performance, low cost, and large-scale production. Single-atom electrocatalysts, with their 100% atomic utilization and unique electronic structure, offer a new approach to solving these problems. However, traditional preparation methods suffer from issues such as the easy aggregation of metal atoms and the strong limitations of the support, restricting their practical application. Summary of the Invention

[0006] Addressing the technical problems of imprecise vacancy concentration control, insufficient catalytic activity, and easy agglomeration of metal atoms in the existing technologies, this application aims to provide a ruthenium single-atom synergistic sulfur vacancy-controlled heterostructure electrocatalyst, its preparation method, and its application. This invention is based on a ruthenium single-atom synergistic sulfur vacancy-controlled MoS2 / Ni... x S y The heterostructure catalyst Ru-Vs-MoS2 / Ni was successfully prepared by electrodeposition, hydrothermal treatment, and chemical etching. x S y @CC's self-supporting electrode material has creatively developed MoS2 / Ni with synergistic regulation of ruthenium single atoms and sulfur vacancies. x S y Heterogeneous electrocatalysts, through precise control of atomic-level dispersion of active sites and optimization of electronic structure, significantly reduce the amount of precious metals used while maintaining excellent catalytic activity. Combined with scalable preparation processes, they can be applied to industrial electrolyzers, providing a breakthrough solution for the commercial application of water electrolysis to produce hydrogen.

[0007] This invention provides the following technical solutions: Technical solution 1 provides a ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst (Ru-V) S -MoS2 / Ni x Sy @CC self-supporting electrode).

[0008] Furthermore, the electrocatalyst uses a carbon cloth substrate (CC) as a conductive self-supporting framework and has a three-dimensional fibrous structure; MoS2 / Ni x S y In-situ growth on the surface of carbon cloth to form MoS2 / Ni x S y Heterogeneous structure, in which MoS2 is rich in sulfur vacancies (V S To enhance the basal catalytic activity; the MoS2 / Ni x S y The heterostructure exhibits a nanosheet morphology; ruthenium single atoms (Ru) are anchored at sulfur vacancies or defect sites in MoS2, serving as an active catalytic component, optimizing the hydrogen adsorption free energy, and promoting the dissociation of water molecules in alkaline media. The Ru single atom refers to atomically dispersed ruthenium.

[0009] The Ni x S y The atomic percentage of nickel is 58–64 at.%, and the atomic percentage of sulfur is 42–36 at.%. The loading of ruthenium single atoms in the catalyst is 0.1–2.0 wt.%.

[0010] Technical solution 2 provides a method for preparing the above-mentioned ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst, including the following steps: S1. Pre-treat the carbon cloth; prepare a choline-based deep eutectic solvent; use the choline-based deep eutectic solvent as the electrolyte, the pre-treated carbon cloth as the working electrode, the nickel sheet as the counter electrode, and the non-mercury electrode as the reference electrode to perform electrode deposition to obtain Ni@CC; S2. Prepare a Na2MoO4 / CH4N2S mixed solution; place the Ni@CC obtained in step S1 into the Na2MoO4 / CH4N2S mixed solution, transfer it to a reaction vessel, and carry out a hydrothermal reaction; after the reaction is completed, allow it to cool naturally, wash, and dry to obtain MoS2 / Ni. x S y @CC material; where x and y take the values: x=1, y=1 and x=3, y=4; S3. The MoS2 / Ni obtained in step S2 x S y @CC is immersed in H2O2 solution to etch sulfur vacancies, and after washing and drying, V is obtained. S -MoS2 / Ni x S y @CC; To prepare a methanol solution of RuCl3, add V S -MoS2 / Ni x S y@CC and a hydrothermal reaction was carried out to finally obtain the target product Ru-V. S -MoS2 / Ni x S y @CC self-supporting electrode material, namely the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst.

[0011] Further, the pretreatment of carbon cloth in step S1 is specifically acid treatment, which involves immersing the carbon cloth in a nitric acid solution with a concentration of 0.5~1.0 mol / L, rinsing it repeatedly with deionized water, and then drying it in a drying oven at 60~80℃ for 6~12 hours.

[0012] Further, the choline-based deep eutectic solvent in step S1 contains 0.1~0.5 mol / L NiCl2, and the concentration of choline is 5~9 mol / L. The preparation steps are as follows: choline chloride and ethylene glycol are mixed at a molar ratio of 1:1.8~1:2.2 (preferably 1:2), and stirred at a constant temperature of 55~65℃ (preferably 60℃) for 20~25h (preferably 24h) under magnetic stirring until a colorless and transparent solution is formed. Then, 0.1~0.5 mol / L NiCl2·6H2O is added, and the mixture is stirred at a constant temperature of 55~65℃ (preferably 60℃) for 10~15h (preferably 12h) to finally obtain a green and transparent solution.

[0013] Furthermore, the electrodeposition time in step S1 is 1 to 3 hours.

[0014] Further, in the Na2MoO4 / CH4N2S mixed solution described in step S2, the concentration of Na2MoO4 is 0.05~0.08 mol / L, and the concentration of CH4N2S is 0.1~0.3 mol / L.

[0015] Furthermore, the conditions for the hydrothermal reaction in step S2 are: 180~220 ℃, 15~24 h, preferably 200 ℃ for 20 h.

[0016] Furthermore, the washing described in step S2 refers to washing with deionized water and ethanol in sequence.

[0017] Further, the concentration of the H2O2 solution in step S3 is 0.2~0.6 mol / L, preferably 0.5 mol / L.

[0018] Furthermore, the etching reaction time in step S3 is 60~30s, preferably 200s.

[0019] Further, the concentration of the methanol solution of RuCl3 prepared in step S3 is 0.002~0.006 mol / L.

[0020] Furthermore, the conditions for the hydrothermal reaction in step S3 are: 100~150℃, 2~6 h, preferably 4 h at 130℃.

[0021] Technical solution 3 provides the application of the above-mentioned ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst, wherein the catalyst is used for catalytic water electrolysis to produce hydrogen, the electrolyte is an alkaline electrolyte, and the product is high-purity hydrogen gas (H2). The alkaline electrolyte is a KOH or NaOH solution with a concentration of 1~5M.

[0022] Compared with the prior art, this application has at least the following improvements and beneficial effects: (1) Existing MoS2-based catalysts suffer from insufficient active sites and low utilization of noble metals in alkaline hydrogen evolution reactions. This invention addresses this problem by precisely anchoring Ru in single-atom form onto MoS2 / Ni. x S y In the heterostructure, and combined with the synergistic regulation of sulfur vacancies, a large number of highly active sites are created on the basal surface, creatively constructing a "Ru single atom-sulfur vacancy-heterojunction" synergistic system. This system is achieved through Ru single atom anchoring and sulfur vacancy (V... S Synergistic effect of ) to precisely regulate MoS2 / Ni x S y The electronic structure was optimized to improve the hydrogen adsorption free energy (ΔG). H* This structure significantly enhances the activity of the hydrogen evolution reaction (HER) under alkaline conditions. It also possesses excellent electronic conductivity and stability, which greatly reduces the amount of precious metals required while ensuring high activity, thus achieving high-efficiency catalytic performance with low precious metal content.

[0023] (2) This invention uses an innovative three-step method of electrodeposition-hydrothermal-liquid phase treatment to prepare Ru-V. S -MoS2 / Ni x S y @CC self-supporting electrode, with precise and controllable process parameters, enables one-step preparation of Ru single-atom modified heterostructure electrocatalysts on a heterostructure support via an optimized low-temperature hydrothermal method. Specifically, a combined process of electrodeposition-hydrothermal-chemical etching is employed, first electrodepositing Ni on carbon cloth, and then synthesizing MoS2 / Ni via hydrothermal method. x S y By constructing sulfur vacancies through selective etching with H2O2 and then using a low-temperature hydrothermal method to precisely anchor Ru single atoms, a synergistic active center of "Ru single atom-sulfur vacancy-heterogeneous structure" was successfully constructed under mild conditions. This avoids the high-temperature treatment and multi-step modification problems of traditional single-atom synthesis methods. The process is simple to operate and easy to scale up, significantly reducing energy consumption and production costs. It also solves the technical problems of insufficient basal activity and easy agglomeration of single atoms in traditional MoS2 catalysts.

[0024] (3) The prepared ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst can be directly used as a self-supporting electrode. While maintaining a low amount of precious metals, it achieves hydrogen evolution activity exceeding that of commercial Pt / C, exhibiting hydrogen evolution catalytic activity superior to that of commercial Pt / C electrocatalysts. The amount of precious metals is reduced by more than 90%, and the electrocatalyst achieves long-term stability of more than 300 hours through the stabilizing effect of sulfur coordination single atoms. This catalyst shows significant application advantages in AEM electrolyzers: it has excellent hydrogen evolution activity and stability comparable to commercial Pt / C, can be directly used as a self-supporting electrode, greatly simplifying the traditional manufacturing process, and can still maintain excellent catalytic performance and structural stability under alkaline working conditions. It solves the cost and stability problems of AEM electrolyzer electrocatalysts and the problems of insufficient activity and poor stability of existing non-precious metal catalysts under alkaline conditions, providing an efficient and reliable solution for the industrial application of water electrolysis hydrogen production technology. Attached Figure Description

[0025] Figure 1 This is a flowchart illustrating the technical process of the present invention. Figure 2 X-ray diffraction patterns of the samples prepared in Example 1 and Comparative Example 1; Figure 3 Transmission electron microscopy (TEM) image (left) and atomic resolution spherical aberration electron microscopy (ASME) image (right) of the sample prepared for Example 1; Figure 4 Performance test graphs of hydrogen production by water electrolysis for samples prepared in Example 1 and Comparative Example 1; Figure 5 The above is a performance test diagram of the AEM electrolytic cell for the sample prepared in Example 1; Figure 6 The image shows the stability test results of the AEM electrolyzer for the sample prepared in Example 1. Detailed Implementation

[0026] To enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be described in detail below with reference to specific embodiments. It should be noted that the following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any way. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0027] Unless otherwise specified, all raw materials used in this invention are not subject to any particular restriction on their source; they can be purchased from the market or prepared using conventional methods known to those skilled in the art. Carbon cloth (CC Suzhou Shengernuo Technology Co., Ltd.), nickel chloride hexahydrate (NiCl2·6H2O, 98%, Shanghai test), sodium molybdate dihydrate (Na2MoO4·2H2O, 99%, Shanghai test), thiourea (CH4N2S, 99%, Shanghai test), hydrogen peroxide (H2O2, 30wt%, Shanghai test), ruthenium trichloride hydrate (RuCl3·xH2O, 38.0-42.0%, Sigma), potassium hydroxide (KOH, 85%, Shanghai test), methanol (CH3OH, 99%, Shanghai test), anhydrous ethanol (C2H5OH, 99%, Shanghai test), commercial platinum-carbon catalyst (20wt%), Nafion solution (5wt%, Beijing Jingke Scientific Instruments Co., Ltd.), choline chloride (C5H 14 ClNO, 98%, Shanghai test), ethylene glycol (CH2OH, 99%, Shanghai test).

[0028] Example 1: A Ru-V S -MoS2 / Ni x S y @CC self-supporting electrode material like Figure 1 As shown, this embodiment provides a Ru-V S -MoS2 / Ni x S y The preparation steps of the @CC self-supporting electrode material (a heterostructure electrocatalyst with ruthenium single atom synergistic sulfur vacancy regulation) are as follows: Preparation of S1.Ni@CC: Pretreatment of carbon cloth (CC): Acid treatment: Immerse the carbon cloth in a nitric acid solution with a concentration of 0.5~1.0 mol / L, rinse repeatedly with deionized water, and then dry in a vacuum drying oven at 60~80℃ for 6~12 hours.

[0029] Preparation of choline-based deep eutectic solvent electrolyte containing 0.2 M NiCl2·6H2O: Choline chloride and ethylene glycol were mixed at a molar ratio of 1:2 and stirred at 60℃ for 24 h under magnetic stirring at 500 rpm. Then, 25 mL of the solution was taken, 1.2 g NiCl2·6H2O was added, and stirring was continued at 60℃ for 3~12 h to obtain a green transparent liquid.

[0030] Using 25 mL of choline-based deep eutectic solvent containing 0.2 M NiCl2·6H2O as the electrolyte, a three-electrode system (pretreated carbon cloth (CC) as the working electrode, a nickel sheet as the counter electrode, and a non-mercury electrode as the reference electrode) was used for electrodeposition at a constant potential of -0.6 V to -0.9 V for 1 to 3 h. After electrodeposition, the carbon cloth (CC) was directly removed, washed with deionized water and ethanol in sequence, and dried to obtain Ni@CC.

[0031] S2.MoS2 / Ni x S y Preparation of @CC: Take 2.5 mmol Na2MoO4·2H2O and 7.5 mmol CH4N2S in the same container, dissolve them in 30 mL of deionized water, and sonicate until completely dissolved to obtain a clear and transparent Na2MoO4 / CH4N2S mixed solution.

[0032] The Ni@CC electrodeposited in step S1 was placed in a Na2MoO4 / CH4N2S mixed solution, transferred to a high-pressure reactor, and reacted at 200℃ for 20 h. After the reaction was completed, it was allowed to cool naturally, washed successively with deionized water and ethanol, and dried to obtain MoS2 / Ni. x S y @CC materials.

[0033] S3.Ru-V S -MoS2 / Ni x S y Preparation of @CC: The MoS2 / Ni obtained in step S2 x S y @CC was immersed in 0.5 mol / L H2O2 solution for 200 seconds to etch sulfur vacancies. After washing and drying, V was obtained. S -MoS2 / Ni x S y @CC. Dissolve 30 mg of RuCl3·xH2O (x represents the number of water molecules of crystallization, usually 3, i.e., RuCl3·3H2O, but may be 1 or 2 depending on the preparation conditions) in 30 mL of methanol, and then add V... S -MoS2 / Ni x S y @CC reacted at 130℃ for 4 hours, eventually yielding the target product Ru-V. S -MoS2 / Ni x S y @CC self-supporting electrode material, namely the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst.

[0034] Comparative Example 1: A MoS2@CC self-supporting electrode material This comparative example only loads MoS2 onto carbon cloth (CC) and does not contain other active ingredients.

[0035] Pretreatment of carbon cloth (CC): Acid treatment: Immerse the carbon cloth in a nitric acid solution with a concentration of 0.5~1.0 mol / L, rinse repeatedly with deionized water, and then dry in a vacuum drying oven at 60~80℃ for 6~12 hours.

[0036] 2.5 mmol Na₂MoO₄·2H₂O and 7.5 mmol CH₄N₂S were placed in the same container and dissolved in 30 mL of deionized water. The solution was sonicated until completely dissolved, yielding a clear and transparent Na₂MoO₄ / CH₄N₂S mixed solution. The treated carbon cloth (CC) was then placed in the Na₂MoO₄ / CH₄N₂S mixed solution and transferred to a high-pressure reactor. The reaction was carried out at 200 °C for 20 h. After the reaction was completed, the material was allowed to cool naturally, washed successively with deionized water and ethanol, and dried to obtain MoS₂@CC material.

[0037] Example 2: A Ru-V S -MoS2 / Ni x S y Performance Characterization of @CC Self-Supporting Electrode Materials The characterization methods used in this embodiment, such as XRD patterns, transmission electron microscopy, and atomic resolution spherical aberration electron microscopy, are all existing technologies, so their methods will not be described in detail.

[0038] The performance testing method for hydrogen production by water electrolysis is as follows: The HER performance is evaluated using a standard three-electrode system in a 1.0 M KOH electrolyte. The Ru-V... S -MoS2 / Ni x S y The @CC electrode was used as the working electrode, the graphite rod as the counter electrode, and the Hg / HgO electrode as the reference electrode. All electrochemical tests were performed on a CHI 1140D / 660E electrochemical workstation. Linear sweep voltammetry (LSV) was used for the measurements at 2 mV·s. -1 The current density-voltage curve was obtained by scanning at a certain rate.

[0039] The performance testing method for the AEM electrolyzer is as follows: in a 1.0 M KOH electrolyte, the electrolyzer is tested at a voltage range of 1.0~2.0 V and a constant voltage of 2 mV·s. -1 The current density-voltage (jV) curve is obtained by scanning the rate.

[0040] The stability test method for the AEM electrolyzer is as follows: at 1.0 M KOH and 60℃, and at 100 mA·cm⁻¹... -2The system operates continuously at a constant current density for 100-500 hours, monitoring voltage changes over time.

[0041] like Figure 2 As shown in the XRD pattern, the Ru-V obtained in Example 1... S -MoS2 / Ni x S y The main characteristic peaks of the @CC self-supporting electrode material sample match the standard peaks of the 2H phase MoS2. After hydrothermal reaction with electrodeposited Ni@CC, new characteristic peaks appeared, corresponding to NiS (PDF #12-0041) and Ni3S4 (PDF #14-1469), respectively, confirming the MoS2 / Ni x S y (x=1, y=1; x=3, y=4) Formation of multiphase heterostructures. With the introduction of S vacancies and Ru atom doping, the interlayer spacing of MoS2 increases, causing the diffraction peaks in the XRD pattern to shift to lower angles. However, no peaks of metallic Ru appear in the figure, indicating that the Ru content is low and may exist in single-atom form. In contrast, MoS2@CC in Comparative Example 1 only shows diffraction peaks of pure-phase MoS2, proving that Ru single-atom doping and Ni... x S y The heterojunction plays a key role in synergistically regulating the spacing of MoS2 layers, thereby improving HER performance.

[0042] from Figure 3 It can be observed that the MoS2 lattice exhibits distinct regions of atomic absence (circled in the left image). These regions of discontinuous arrangement of locally missing atoms represent the successfully introduced sulfur vacancies (S-vacancy). Meanwhile, Ru-V... S -MoS2 / Ni x S y The @CC self-supporting electrode material sample shows uniformly distributed white bright spots (brighter contrast points). These bright spots correspond to Ru atoms dispersed in single-atom form (circled in the right image), confirming the presence of Ru single atoms in V. S -MoS2 / Ni x S y Successful anchoring on the substrate. These structural features collectively validate the successful construction of the "S vacancy-Ru single atom" synergistic system, providing abundant active sites for the catalyst.

[0043] from Figure 4 As can be seen from the example, the Ru-V obtained in Example 1 S -MoS2 / Ni x S yThe @CC self-supporting electrode material sample exhibits a hydrogen evolution overpotential of only 14 mV at a current density of 10 mA / cm², exceeding the performance of commercial Pt / C catalysts, while maintaining a Ru mass fraction below 2.0 wt.%, demonstrating a significant cost advantage. However, the MoS₂@CC self-supporting electrode material obtained in Comparative Example 1 shows a hydrogen evolution overpotential as high as 145 mV at the same current density. This result fully demonstrates the ultra-high atom utilization efficiency of the "Ru single atom-S vacancy" synergistic system, significantly enhancing the intrinsic activity of its catalytic active sites.

[0044] from Figure 5 As can be seen from the example, the Ru-V obtained in Example 1 S -MoS2 / Ni x S y The @CC self-supporting electrode material sample outperformed commercial Pt / C catalysts in practical electrolyzer applications, a result that fully reveals its potential for industrial application.

[0045] from Figure 6 As can be seen from the example, the Ru-V obtained in Example 1 S -MoS2 / Ni x S y The @CC self-supporting electrode material sample exhibited stable performance for over 300 hours during actual operation in the electrolytic cell, fully demonstrating its feasibility for industrial application.

[0046] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst, characterized in that, The heterostructured electrocatalyst is Ru-V. S -MoS2 / Ni x S y @CC self-supporting electrode; CC represents carbon cloth, and the electrocatalyst uses a carbon cloth substrate as a conductive self-supporting skeleton and has a three-dimensional fiber structure. MoS2 / Ni x S y In-situ growth on the surface of carbon cloth to form MoS2 / Ni x S y Heterogeneous structure, in which MoS2 is rich in sulfur vacancies V S To enhance the basal catalytic activity; the MoS2 / Ni x S y The heterostructure exhibits a nanosheet-like morphology; Ruthenium single atoms are anchored at sulfur vacancies or defect sites in MoS2, serving as an active catalytic component.

2. The ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 1, characterized in that, The Ni x S y The atomic percentage of nickel is 58–64 at.%, and the atomic percentage of sulfur is 42–36 at.%. The loading of ruthenium single atoms in the catalyst is 0.1–2.0 wt.%.

3. A method for preparing a heterostructure electrocatalyst with ruthenium single-atom synergistic sulfur vacancy regulation as described in any one of claims 1-2, characterized in that, Includes the following steps: S1. Pre-treat the carbon cloth; prepare an electrolyte based on a choline-based deep eutectic solvent; Ni@CC was obtained by electrodeposition using a choline-based deep eutectic solvent with added NiCl2 as the electrolyte, pretreated carbon cloth as the working electrode, a nickel sheet as the counter electrode, and a non-mercury electrode as the reference electrode. S2. Prepare a Na2MoO4 / CH4N2S mixed solution; place the Ni@CC obtained in step S1 into the Na2MoO4 / CH4N2S mixed solution, transfer it to a reaction vessel, and carry out a hydrothermal reaction; after the reaction is completed, allow it to cool naturally, wash, and dry to obtain MoS2 / Ni. x S y @CC materials; S3. The MoS2 / Ni obtained in step S2 x S y @CC is immersed in H2O2 solution to etch sulfur vacancies, and after washing and drying, V is obtained. S -MoS2 / Ni x S y @CC; To prepare a methanol solution of RuCl3, add V S -MoS2 / Ni x S y @CC and a hydrothermal reaction was carried out to finally obtain the target product Ru-V. S -MoS2 / Ni x S y @CC self-supporting electrode material, namely the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst.

4. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 3, characterized in that, The pretreatment of carbon cloth described in step S1 specifically involves acid treatment; The choline-based deep eutectic solvent in step S1 contains 0.1~0.5 mol / L NiCl2; The electrodeposition time in step S1 is 1 to 3 hours.

5. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 4, characterized in that, The acid treatment step is as follows: immerse the carbon cloth in a nitric acid solution with a concentration of 0.5~1.0mol / L, rinse repeatedly with deionized water, and then dry in a drying oven at 60~80℃ for 6~12 hours; The preparation steps of the choline-based deep eutectic solvent are as follows: choline chloride and ethylene glycol are mixed at a molar ratio of 1:1.8 to 1:2.2, and stirred at a constant temperature of 55 to 60°C for 20 to 25 hours until a colorless and transparent solution is formed. Then, 0.1 to 0.5 mol / L of NiCl2 is added, and the mixture is stirred at a constant temperature of 55 to 65°C for 10 to 15 hours to finally obtain a green and transparent solution.

6. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 3, characterized in that, The values ​​of x and y in step S2 are: x=1, y=1 and x=3, y=4; In the Na2MoO4 / CH4N2S mixed solution described in step S2, the concentration of Na2MoO4 is 0.05~0.08 mol / L and the concentration of CH4N2S is 0.1~0.3 mol / L.

7. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 3, characterized in that, The conditions for the hydrothermal reaction in step S2 are: 180~220℃, 15~24h.

8. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 3, characterized in that, The concentration of the H2O2 solution in step S3 is 0.2~0.6 mol / L; the etching reaction time in step S3 is 60~300s; and the concentration of the methanol solution for preparing RuCl3 in step S3 is 0.002~0.006 mol / L.

9. The method for preparing the ruthenium single-atom synergistic sulfur vacancy-regulated heterostructure electrocatalyst according to claim 3, characterized in that, The conditions for the hydrothermal reaction in step S3 are: 100~150 ℃, 2~6 h.

10. The application of a heterostructure electrocatalyst with ruthenium single-atom synergistic sulfur vacancy regulation as described in any one of claims 1-2, characterized in that, The catalyst is used to catalyze the electrolysis of water to produce hydrogen. The electrolyte is an alkaline electrolyte, and the product is high-purity hydrogen. The alkaline electrolyte is a KOH or NaOH solution with a concentration of 1~5 M.

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