Tungsten disulfide self-supporting integrated electrode catalyst and preparation method and application thereof

Abstract

The invention provides a tungsten disulfide self-supporting integrated electrode catalyst and a preparation method and application thereof. Aiming at the problems that the conventional block tungsten disulfide is poor in conductivity, and most active edge sites are buried in a stacked layered structure, so that the intrinsic activity and active site exposure rates of the conventional block tungsten disulfide are not ideal, the invention provides the nano tungsten disulfide with the obvious crack interlaced structure; crack-shaped layer gaps with the thickness of 3-5 microns are formed among the units due to interlayer action; a large number of tiny flower-shaped secondary structures are uniformly distributed on the surface of each sheet-shaped unit, and the secondary structures are formed by gathering sheet-shaped crystal forms with the size of 0.5-1 mu m and are in a randomly-arranged flower cluster form. The overpotentials of the catalyst under the current density of 10 mA / cm and 100 mA / cm are only 36 mV and 73 mV respectively, the electrocatalytic performance is excellent, the preparation method is simple and rapid, the reaction temperature is low, the repeatability is good, and the catalyst is especially suitable for continuous large-scale industrial production.

Description

Technical Field

[0001] This invention belongs to the field of electrocatalytic materials technology, specifically relating to a tungsten disulfide self-supporting integrated electrode catalyst, its preparation method, and its application. Background Technology

[0002] Hydrogen energy, due to its high energy density and clean, carbon-free nature, is considered an important component of the future energy system. Electrolysis of water is currently a crucial method for obtaining high-purity hydrogen, with the core challenge being the development of efficient, stable, and low-cost electrocatalysts to reduce the overpotential of the hydrogen evolution reaction. Tungsten disulfide, as a typical two-dimensional transition metal chalcogenide, exhibits broad application prospects in reactions such as water splitting, oxygen reduction, and nitrogen reduction due to its unique electronic structure and excellent electrocatalytic performance. However, existing conventional bulk tungsten disulfide has poor conductivity, and most active edge sites are buried in the stacked layered structure, resulting in unsatisfactory intrinsic activity and active site exposure rates.

[0003] Currently, strategies to improve the catalytic performance of tungsten disulfide mainly include: nano-sizing to increase specific surface area, compositing with highly conductive substrates (such as carbon materials) to promote electron transport, and constructing defects or performing heteroatom doping to adjust the electronic structure. Chinese patent application CN202210400373.2 reports a tungsten disulfide composite nanoparticle and its preparation method, along with its application in the electrocatalysis of the hydrogen evolution reaction. The core of this method is the preparation of tungsten disulfide composite nanoparticles using pulsed laser deposition combined with a rapid annealing method. Chinese patent application CN201810289107.0 reports an oxygen plasma locally enhanced WS2 / RGO material, its preparation, and an electrocatalytic hydrogen production device and its preparation method. This method employs a one-step hydrothermal method to load tungsten disulfide onto redox graphene, and utilizes oxygen plasma treatment to construct more catalytically active sites on the WS2 surface, thus enabling its application in the field of electrocatalysis.

[0004] However, the above-mentioned technical solutions also have obvious defects: on the one hand, the pulsed laser deposition and rapid annealing process of CN202210400373.2, the hydrothermal synthesis, oxygen plasma treatment and micro-nano device assembly process of CN201810289107.0 all involve multiple precise operations, and the overall process is complex and cumbersome; on the other hand, neither of the two solutions has completely solved the problem of poor bonding between the catalyst and the substrate, and if conventional binders are used to directly coat the tungsten disulfide catalyst onto the electrode, not only will the catalytic active sites be easily covered by the binder, resulting in a decrease in the utilization rate of the reaction sites, but the catalyst will also detach due to insufficient bonding between the catalyst and the substrate.

[0005] In summary, developing an integrated tungsten disulfide-based electrode with high conductivity channels, high active site exposure rate, and structural stability is crucial for promoting its practical application. Summary of the Invention

[0006] To address the problems of poor conductivity and the fact that most active edge sites are buried in the stacked layered structure of conventional bulk tungsten disulfide, resulting in unsatisfactory intrinsic activity and active site exposure, this invention provides a tungsten disulfide with a specific and distinct crack-interwoven morphology, endowing the catalyst with high conductivity and high active site density. Simultaneously, since the tungsten disulfide is grown directly on a tungsten metal mesh, a robust integrated (self-supporting, monolithic catalyst) catalyst system is constructed. During synthesis, the tungsten metal mesh is used as a raw material; in the catalytic stage, thanks to the support of the highly conductive metal mesh, each layer and each part of the catalyst receives an ample electron supply, significantly improving the electron transport efficiency within the catalyst layer and greatly enhancing the material's conductivity. In the testing stage, the catalyst directly grown on the tungsten metal mesh constitutes an integrated electrode, eliminating the need for other supports. This effectively avoids the catalyst reloading problem present in traditional catalyst testing, reducing costs and significantly improving catalyst stability and lifespan.

[0007] To achieve the above objectives, the present invention provides a tungsten disulfide self-supporting integrated electrode catalyst, wherein the microstructure of the tungsten disulfide self-supporting integrated electrode catalyst is an interwoven structure with obvious cracks: the main body of the interwoven structure is composed of plate-like units, and crack-like gaps with a thickness of 3-5 μm are formed between the units due to interlayer interaction; and on the surface of each plate-like unit, a large number of tiny flower-like secondary structures are distributed, which are formed by the aggregation of plate-like crystals with a size of 0.5-1 μm, and present as a randomly arranged flower cluster.

[0008] In a preferred embodiment, the tungsten disulfide self-supporting integrated electrode catalyst has overpotentials of 36 mV and 73 mV relative to the reversible hydrogen electrode in 0.5 M H2SO4 electrolyte at current densities of 10 mA / cm² and 100 mA / cm², respectively.

[0009] Another objective of this invention is to provide a method for preparing the above-mentioned tungsten disulfide self-supporting integrated electrode catalyst, specifically using sulfur powder as a sulfur source, tungsten mesh as a tungsten source, chemical vapor deposition technology, and rapid cooling method to prepare tungsten disulfide covering a tungsten mesh substrate.

[0010] This invention provides a self-supporting integrated electrode catalyst for tungsten disulfide with a specific morphology. The designed preparation method is simple and safe, with a low reaction temperature, and eliminates the need for a substrate, thus avoiding the introduction of impurities. Precise control of the nanostructure can be achieved through efficient and rapid methods. The resulting tungsten disulfide self-supporting integrated electrode catalyst, due to its distinct interwoven crack structure and fully exposed active sites, offers high activity and high stability, making it widely applicable in the field of nanomaterial electrocatalysis and possessing broad industrial prospects.

[0011] To achieve the above objectives, the present invention provides a method for preparing the above-mentioned tungsten disulfide self-supporting integrated electrode catalyst, specifically including the following steps:

[0012] In a dual-temperature zone chemical vapor deposition system, sulfur powder is placed upstream of the gas path, and a tungsten metal mesh is placed downstream of the gas path. Chemical vapor deposition is carried out sequentially through a heating program and an isothermal program. After the isothermal program is completed, rapid cooling is performed to obtain the tungsten disulfide self-supporting integrated electrode catalyst with a distinct crack-interwoven structure.

[0013] In a preferred embodiment, the sulfur powder is of analytical grade, with a particle size ≤75μm, and the amount of sulfur powder used is 0.05-0.3g.

[0014] In a preferred embodiment, the tungsten metal mesh has a purity of ≥99.95% and a mesh size of 150-200 mesh; preferably, the area of ​​the tungsten metal mesh is 5*5cm. 2 More preferably, the area of ​​the tungsten metal mesh is 1*1cm. 2 The corresponding sulfur powder dosage is 0.05-0.15g; most preferably, the tungsten mesh is a tungsten mesh that has undergone ultrasonic pretreatment; the purpose of ultrasonic cleaning is to remove impurities from the surface of the tungsten mesh, so conventional pretreatment methods known to those skilled in the art can be used, such as cleaning with deionized water and anhydrous ethanol for 1000-3000s at room temperature.

[0015] In a preferred embodiment, the heating process includes: heating from room temperature to 350°C in the upstream gas path where the sulfur powder is located over 20-60 minutes; heating from room temperature to 650°C in the downstream gas path where the tungsten mesh is located over 20-60 minutes; and heating the areas where the sulfur powder and the tungsten mesh are located simultaneously.

[0016] In a preferred embodiment, the heating rate upstream of the gas path containing the sulfur powder is 5-15℃ / min; the heating rate downstream of the gas path containing the tungsten mesh is 10-20℃ / min; preferably, the heating rate upstream of the gas path containing the sulfur powder is 7.5℃ / min; and the heating rate downstream of the gas path containing the tungsten mesh is 16.25℃ / min.

[0017] In a preferred embodiment, the isothermal program includes: maintaining a temperature of 350°C for 1-30 minutes upstream of the gas path containing the sulfur powder; and maintaining a temperature of 650°C for 1-30 minutes downstream of the gas path containing the tungsten mesh.

[0018] In a preferred embodiment, the carrier gas used in the heating program and / or the isothermal program is argon, and the flow rate of the carrier gas is 50-150 sccm; preferably, the flow rate of the carrier gas used in the heating program and the isothermal program is the same; more preferably, the flow rate of argon used in the heating program and the isothermal program is 100 sccm.

[0019] The carrier gas flow rate has a significant impact on the formation and morphology of nanostructures. A higher carrier gas flow rate can enhance the transport efficiency of reactant molecules, which helps to form uniform nanostructures, but may also promote rapid consumption of raw materials and premature deposition of products. Conversely, a lower carrier gas flow rate may cause reactants to remain in the reaction chamber for too long, resulting in localized overheating and uneven growth. Therefore, the appropriate carrier gas flow rate designed in this invention is crucial for achieving the ideal crack-interwoven structure and flower cluster morphology. Furthermore, because the thermodynamic conditions for WS2 synthesis are relatively mild, and the sulfur source (S) is highly volatile and reactive, it is sufficient to directly sulfide the tungsten source. Therefore, using only chemically stable and safe argon as the carrier gas allows for the simple and efficient preparation of high-quality WS2.

[0020] In a preferred embodiment, the rapid cooling specifically includes the following steps: after the constant temperature is completed, immediately open the insulation cover of the tubular furnace and continuously introduce argon gas at a flow rate of 200-600 sccm, cooling to room temperature within 5-15 minutes.

[0021] In this invention, a strategy of rapidly cooling by opening the insulation cover and flushing with high-throughput carrier gas is adopted. The purpose is to synthesize tungsten disulfide with an interwoven structure with obvious cracks and abundant edge defects. Therefore, the defined conditions are significant for the preparation of high-quality materials.

[0022] Compared with the prior art, the technical solution of the present invention has the following advantages:

[0023] This invention employs atmospheric pressure chemical vapor deposition (CVD) to rapidly and with low energy consumption prepare tungsten disulfide self-supporting integrated electrode catalysts that combine high activity and high stability. The designed method exhibits good reproducibility and is simple to operate, making it particularly suitable for continuous large-scale industrial production.

[0024] The catalyst prepared in this invention uses a tungsten mesh as a conductive substrate to construct a self-supporting integrated structure. This integrated design significantly improves the material's conductivity and structural stability, while avoiding the transfer and loading steps required in traditional powder or thin-film catalyst testing. This reduces testing costs and further optimizes electron transport performance. Furthermore, by introducing a rapid cooling step during chemical vapor deposition synthesis, a distinctly cracked interwoven structure, numerous micron-sized flower-like secondary structures, and abundant edge defects were successfully induced. In a three-electrode system hydrogen evolution reaction test, the catalyst exhibited overpotentials of only 36 mV and 73 mV at current densities of 10 mA / cm² and 100 mA / cm², respectively, demonstrating electrocatalytic performance comparable to commercial noble metal Pt / C catalysts (Pt / C exhibits overpotentials of 50 mV and 148 mV at the same current densities). Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the experimental apparatus for preparing tungsten disulfide self-supporting integrated electrode catalyst by chemical vapor deposition according to the present invention.

[0027] Figure 2 This is a scanning electron microscope image of tungsten disulfide nanoparticles grown on a tungsten mesh substrate as obtained in Example 1 of the present invention.

[0028] Figure 3 This is a scanning electron microscope image of the tungsten disulfide nanoparticles grown on a tungsten mesh substrate obtained in Comparative Example 1 of the present invention.

[0029] Figure 4 This is a transmission electron microscope image of tungsten disulfide nanoparticles grown on a tungsten mesh substrate as obtained in Example 1 of the present invention.

[0030] Figure 5 This is the Raman spectrum of tungsten disulfide nanoparticles grown on a tungsten mesh substrate obtained in Example 1 of the present invention;

[0031] Figure 6 The image shows the X-ray diffraction pattern of tungsten disulfide nanoparticles grown on a tungsten mesh substrate obtained in Example 1 of this invention.

[0032] Figure 7The figure shows the current density-electrode potential curves in the electrochemical hydrogen evolution reaction using the tungsten disulfide self-supporting integrated electrode obtained in Example 1 and Comparative Example 1 of this invention as the cathode catalyst in 0.5M H2SO4 electrolyte.

[0033] Figure 8 The tungsten disulfide self-supporting integrated electrode obtained in Example 1 of this invention was subjected to a 100-hour constant current test in 0.5M H2SO4 with a current density of 100 mA / cm². Detailed Implementation

[0034] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. However, it should be understood that the scope of protection of the present invention is not limited to the specific embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0035] The technical solution of this application will be described in detail below through specific embodiments. Figure 1 This is a schematic diagram of the synthesis process of the present invention. The synthesis process adopts a chemical vapor deposition dual-temperature zone synthesis method, with sulfur powder and tungsten metal mesh as reaction raw materials, respectively.

[0036] Unless otherwise specified, the technical means used in this invention are conventional means well known to those skilled in the art. All raw materials, reagents, instruments, and equipment used in this invention can be purchased commercially or prepared using existing methods. Unless otherwise specified, all reagents used in this invention are of analytical grade. In this invention, the room temperature is 25±2℃.

[0037] Example 1

[0038] A method for preparing a tungsten disulfide self-supporting integrated electrode includes the following steps:

[0039] Prepare a tungsten metal mesh and wash it with deionized water and anhydrous ethanol for 1000s at room temperature to obtain a tungsten source.

[0040] In a dual-temperature zone chemical vapor deposition system, 0.05 g of sulfur powder was weighed and placed in a quartz boat in the left temperature zone of the tubular furnace. Figure 1 T1 zone), tungsten mesh (area 1*1 cm) 2 ) placed in the quartz boat in the right-side temperature zone of the tube furnace ( Figure 1 (T2 zone in the middle).

[0041] Before heating, a vacuum is first evacuated to purge the air from the tube furnace. Then, argon gas is introduced as a carrier gas at a flow rate of 100 sccm, and this flow rate is maintained continuously at 100 sccm during both the heating and isothermal programs. Specific heating and isothermal programs are as follows:

[0042] During the heating process, the upstream of the gas path containing sulfur powder is heated from room temperature to 300℃ in 40 minutes at a rate of 7.5℃ / min; at the same time, the downstream of the gas path containing tungsten mesh is heated from room temperature to 650℃ in 40 minutes at a rate of 16.25℃ / min.

[0043] During the isothermal program, the upstream gas path containing sulfur powder is kept at 300℃ for 10 minutes, while the downstream gas path containing tungsten mesh is kept at 650℃ for 10 minutes.

[0044] After the constant temperature is completed, the insulation cover of the tubular furnace is immediately opened for rapid cooling, and argon gas with a flow rate of 500 sccm is continuously introduced. It can be cooled to room temperature in 10 minutes, thus obtaining the tungsten disulfide self-supporting integrated electrode.

[0045] Example 2

[0046] A method for preparing a tungsten disulfide self-supporting integrated electrode includes the following steps:

[0047] Prepare a tungsten metal mesh and wash it with deionized water and anhydrous ethanol for 2000s at room temperature to obtain a tungsten source.

[0048] In a dual-temperature zone chemical vapor deposition system, 0.1 g of sulfur powder is weighed and placed in a quartz boat in the left temperature zone of the tubular furnace. A tungsten mesh (with an area of ​​1*1 cm) is used. 2 It is placed in a quartz boat in the right-side temperature zone of the tube furnace.

[0049] Before heating, a vacuum is first evacuated to purge the air from the tube furnace. Then, argon gas is introduced as a carrier gas at a flow rate of 100 sccm, and this flow rate is maintained continuously at 100 sccm during both the heating and isothermal programs. Specific heating and isothermal programs are as follows:

[0050] During the heating process, the upstream gas path containing sulfur powder is heated from room temperature to 300℃ at a rate of 7.5℃ / min over 40 minutes; simultaneously, the downstream gas path containing tungsten mesh is heated from room temperature to 650℃ at a rate of 16.25℃ / min over 40 minutes.

[0051] In the isothermal program, the upstream gas path containing sulfur powder is kept at 300℃ for 15 minutes, and the downstream gas path containing tungsten mesh is kept at 650℃ for 15 minutes.

[0052] After the constant temperature is completed, the insulation cover of the tubular furnace is immediately opened for rapid cooling, and argon gas with a flow rate of 500 sccm is continuously introduced. It can be cooled to room temperature in 10 minutes, thus obtaining the tungsten disulfide self-supporting integrated electrode.

[0053] Example 3

[0054] A method for preparing a tungsten disulfide self-supporting integrated electrode includes the following steps:

[0055] Prepare a tungsten metal mesh and wash it with deionized water and anhydrous ethanol for 3000s at room temperature to obtain a tungsten source.

[0056] In a dual-temperature zone chemical vapor deposition system, 0.15 g of sulfur powder is weighed and placed in a quartz boat in the left temperature zone of the tubular furnace. A tungsten mesh (with an area of ​​1*1 cm) is also placed inside. 2 It is placed in a quartz boat in the right-side temperature zone of the tube furnace.

[0057] Before heating, a vacuum is first evacuated to purge the air from the tube furnace. Then, argon gas is introduced as a carrier gas at a flow rate of 100 sccm, and this flow rate is maintained continuously at 100 sccm during both the heating and isothermal programs. Specific heating and isothermal programs are as follows:

[0058] During the heating process, the upstream gas path containing sulfur powder is heated from room temperature to 300℃ at a rate of 7.5℃ / min over 40 minutes; simultaneously, the downstream gas path containing tungsten mesh is heated from room temperature to 650℃ at a rate of 16.25℃ / min over 40 minutes.

[0059] In the isothermal program, the upstream gas path containing sulfur powder is kept at 300℃ for 20 minutes, and the downstream gas path containing tungsten mesh is kept at 650℃ for 30 minutes.

[0060] After the constant temperature is completed, the insulation cover of the tubular furnace is immediately opened for rapid cooling, and argon gas with a flow rate of 500 sccm is continuously introduced. It can be cooled to room temperature in 10 minutes, thus obtaining the tungsten disulfide self-supporting integrated electrode.

[0061] Comparative Example 1

[0062] A method for preparing a tungsten disulfide self-supporting integrated electrode includes the following steps:

[0063] Prepare a tungsten metal mesh and wash it with deionized water and anhydrous ethanol for 1000s at room temperature to obtain a tungsten source.

[0064] In a dual-temperature zone chemical vapor deposition system, 0.05 g of sulfur powder is weighed and placed in a quartz boat in the left temperature zone of the tubular furnace. A tungsten mesh (with an area of ​​1*1 cm) is also placed inside. 2 It is placed in a quartz boat in the right-side temperature zone of the tube furnace.

[0065] Before heating, a vacuum is first evacuated to purge the air from the tube furnace. Then, argon gas is introduced as a carrier gas at a flow rate of 100 sccm, and this flow rate is maintained continuously at 100 sccm during both the heating and isothermal programs. Specific heating and isothermal programs are as follows:

[0066] During the heating process, the upstream of the gas path containing sulfur powder is heated from room temperature to 300℃ in 40 minutes at a rate of 7.5℃ / min; at the same time, the downstream of the gas path containing tungsten mesh is heated from room temperature to 650℃ in 40 minutes at a rate of 16.25℃ / min.

[0067] In the isothermal program, the upstream gas path containing sulfur powder is kept at 300℃ for 10 minutes, and the downstream gas path containing tungsten mesh is kept at 650℃ for 10 minutes.

[0068] After the isothermal period, the insulated cover of the tubular furnace was kept closed, and argon gas was continuously introduced at a flow rate of 100 sccm. After 60 minutes, the device was cooled to room temperature, and a tungsten disulfide self-supporting integrated electrode was obtained.

[0069] Application Example 1

[0070] The nano-tungsten disulfide prepared in Example 1 was characterized, and the results are as follows: Figure 2-5 As shown.

[0071] in, Figure 2 The image shown is a scanning electron microscope (SEM) image of the nano-tungsten disulfide obtained in Example 1, compared to the nano-tungsten disulfide prepared in Comparative Example 1. Figure 3 The material obtained in Example 1 has obvious large cracks and a large number of tiny flower-like and flaky structures on its surface.

[0072] Figure 4 The image shows a transmission electron microscope (TEM) image of the nano-tungsten disulfide obtained in Example 1. As can be seen from the image, the tungsten disulfide has a regular edge structure under TEM. The interplanar spacings of 0.23 nm and 0.27 nm correspond to the (013) and (011) crystal planes of WS2, respectively, which proves that the material is WS2.

[0073] Figure 5 The figure shows the Raman spectrum of the nano-tungsten disulfide obtained in Example 1. The A spectrum of WS2 is also shown. 1g The vibration signal verified the successful synthesis of WS2.

[0074] Figure 6 The X-ray diffraction of the nano-tungsten disulfide obtained in Example 1 shows that the diffraction peaks in the figure are in good agreement with the standard PDF card of WS2, indicating that WS2 was successfully synthesized.

[0075] Application Example 2

[0076] The electrochemical performance of the tungsten disulfide self-supporting integrated electrodes prepared in Example 1 and Comparative Example 1 was tested. The specific experimental methods included:

[0077] Linear sweep voltammetry (LSV) measurements were performed on an electrochemical workstation (CHI660E). A W-grid-supported nano-WS2 catalyst was used as the working electrode, and Ag / AgCl and Pt electrodes were used as the reference and counter electrodes, respectively. All potentials mentioned are related to the reversible hydrogen electrode (RHE): E RHE =E （Ag / AgCl） +0.059*pH +0.197 V. Electrochemical measurements were performed in 0.5 M H₂SO₄. High-purity Ar gas was bubbled into the electrolyte for 30 min prior to measurement. Linear sweep voltammetry (LSV) measurements were performed at a scan rate of 5 mV / s between 0 and -0.6 V relative to Ag / AgCl. All results were corrected for 95% ohmic potential drop (iR).

[0078] Results and Discussion:

[0079] Figure 7 The electrocatalytic performance of the tungsten disulfide self-supporting integrated electrode, the commercial noble metal Pt / C catalyst, and the metal W mesh prepared in Example 1 and Comparative Example 1 were compared. The figures show that the material obtained in Example 1 exhibited better electrocatalytic performance at 10 and 100 mA / cm². 2 The overpotentials at current densities were 36 mV and 72 mV, respectively, exhibiting electrocatalytic performance comparable to commercial noble metal Pt / C catalysts, far superior to the electrochemical performance of the material prepared in Comparative Example 1, while also demonstrating good cycling stability. Figure 8 ).

[0080] In summary, the experiments show that the present invention successfully prepared a self-supporting integrated electrode catalyst of tungsten disulfide, which has a large number of edge active sites and effectively solved the problems of weak bonding between traditional powdered tungsten disulfide catalysts and substrates and increased interfacial resistance caused by the use of insulating polymer binders. It exhibits excellent electrocatalytic activity in the HER catalysis process.

[0081] The foregoing description of specific exemplary embodiments of the invention is for illustrative and explanatory purposes. These descriptions are not intended to limit the invention to the precise forms disclosed, and it will be apparent that many changes and variations can be made in accordance with the foregoing teachings. The exemplary embodiments were chosen and described in order to explain the specific principles of the invention and its practical application, thereby enabling those skilled in the art to implement and utilize various different exemplary embodiments of the invention, as well as various different choices and variations. The scope of the invention is intended to be defined by the claims and their equivalents.

Claims

1. A tungsten disulfide self-supporting integrated electrode catalyst, characterized in that, The microstructure of the tungsten disulfide is an interwoven structure with obvious cracks: the main body of the interwoven structure is composed of plate-like units, and crack-like gaps with a thickness of 3-5 μm are formed between the units due to interlayer interaction; and on the surface of each plate-like unit, a large number of tiny flower-like secondary structures are distributed, which are formed by the aggregation of plate-like crystals with a size of 0.5-1 μm, and present as a randomly arranged flower cluster.

2. The tungsten disulfide self-supporting integrated electrode catalyst as described in claim 1, characterized in that, The tungsten disulfide self-supporting integrated electrode catalyst, in 0.5M H2SO4 electrolyte, has overpotentials of 36mV and 73mV relative to the reversible hydrogen electrode at current densities of 10mA / cm² and 100mA / cm², respectively.

3. The method for preparing the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 1 or 2, characterized in that, Includes the following steps: In a dual-temperature zone chemical vapor deposition system, sulfur powder is placed upstream of the gas path, and a tungsten metal mesh is placed downstream of the gas path. Chemical vapor deposition is carried out sequentially through a heating program and an isothermal program. After the isothermal program is completed, rapid cooling is performed to obtain the tungsten disulfide self-supporting integrated electrode catalyst with a distinct crack-interwoven structure.

4. The preparation method of the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 3, characterized in that, The heating process includes: heating from room temperature to 350°C in the upstream gas path where the sulfur powder is located over 20-60 minutes; and simultaneously heating from room temperature to 650°C in the downstream gas path where the tungsten mesh is located over 20-60 minutes.

5. The method for preparing the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 4, characterized in that, The heating rate upstream of the gas path containing the sulfur powder is 5-15℃ / min; the heating rate downstream of the gas path containing the tungsten mesh is 10-20℃ / min.

6. The method for preparing the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 3, characterized in that, The constant temperature program includes: maintaining a temperature of 350°C for 1-30 minutes upstream of the gas path where the sulfur powder is located; and maintaining a temperature of 650°C for 1-30 minutes downstream of the gas path where the tungsten mesh is located.

7. The method for preparing the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 3, characterized in that, In the heating program and / or the isothermal program, the carrier gas used is argon, and the flow rate of the carrier gas is 50-150 sccm.

8. The method for preparing the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 3, characterized in that, The rapid cooling specifically includes the following steps: after the constant temperature is completed, immediately open the insulation cover of the tubular furnace and continuously introduce argon gas at a flow rate of 200-600 sccm, cooling to room temperature within 5-15 minutes.

9. The application of the tungsten disulfide self-supporting integrated electrode catalyst as described in claim 1 or 2 in the field of electrocatalysis.

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