A method for controllable preparation of a two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template.

Abstract

This invention belongs to the field of controllable preparation technology of high-entropy nanomaterials and water electrolysis catalysts, specifically disclosing a method for preparing a high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template. At least five metal precursors are added to deionized water, followed by ammonium fluoride and urea. The mixture is ultrasonically mixed and stirred to obtain a template two-dimensional high-entropy hydroxide. The obtained two-dimensional high-entropy hydroxide template is placed in the center of a single-temperature zone tube furnace, and argon gas is continuously introduced into a quartz tube. A sulfidation reaction is carried out under an argon atmosphere to obtain the target product, the two-dimensional high-entropy sulfide. This invention's method for synthesizing two-dimensional high-entropy sulfides solves problems such as high synthesis temperature, uneven element distribution, and unstable two-dimensional structure, avoiding phase separation and segregation phenomena that occur during high-temperature synthesis. This reduces production costs and process difficulty, and allows for the synthesis of a series of high-performance two-dimensional high-entropy sulfide water electrolysis catalysts.

Description

I. Technical Field:

[0001] This invention relates to a high-throughput, universal, and low-cost controllable low-temperature synthesis technology for two-dimensional high-entropy sulfide water electrolysis catalysts, belonging to the field of controllable preparation technology of high-entropy nanomaterials and water electrolysis catalysts. Specifically, it relates to a method for controllably preparing two-dimensional high-entropy sulfide high-efficiency water electrolysis catalysts based on two-dimensional high-entropy hydroxide templates. II. Background Technology:

[0002] The excessive consumption of non-renewable fossil fuels has exacerbated the global energy and environmental crisis, leading to an urgent need for the development of clean, efficient, and sustainable energy conversion technologies. Water electrolysis for hydrogen production is a clean, efficient, green, and scalable energy conversion process. Theoretically, the water decomposition voltage is 1.23V, but in practice, the industrial water decomposition voltage is 1.8V–2.0V. This is due to the existence of the water dissociation energy barrier, resulting in overpotential (actual water electrolysis voltage minus theoretical water electrolysis voltage). Overpotential leads to increased resource consumption during water decomposition, causing a rapid increase in hydrogen production costs. Therefore, there is an urgent need to develop a low-cost, low-overpotential, high-performance water electrolysis catalyst to realize the industrialization of water electrolysis for hydrogen production.

[0003] Two-dimensional high-entropy sulfides are two-dimensional nanomaterial systems composed of five or more elements in approximately equiatomic proportions. Their structure possesses ultrathin two-dimensional planar characteristics, resulting in highly exposed surface active sites. The mixture of multiple elements contributes to rich surface chemical properties and diverse electronic structures. The presence of these multiple elements provides a large number of surface active sites, enabling two-dimensional high-entropy sulfides to exhibit higher activity and selectivity in catalytic reactions. For example, in the electrocatalytic hydrogen evolution reaction (HER), they demonstrate excellent catalytic performance, reducing reaction overpotential and increasing reaction rate. Furthermore, the synergistic effect between different elements can optimize the electronic structure and physicochemical properties of the material, making it superior to single-component materials in fields such as energy storage and catalysis. By changing the types and proportions of elements, the performance of two-dimensional high-entropy sulfides can be precisely controlled to meet the needs of different application scenarios. The complex configuration resulting from the high-entropy structure and the interactions between multiple elements typically result in excellent thermal and chemical stability, maintaining structural and performance stability under harsh environmental conditions. However, due to the high sulfidation temperature of sulfides and the tendency for phase / structure segregation to occur at high temperatures, the synthesis of two-dimensional high-entropy sulfides faces significant challenges. Achieving uniform mixing of different elements and controlling their ultrathin thickness requires precise control of temperature, pressure, and energy fields to achieve the desired properties in terms of size, phase, shape, cross-section, and surface decoration. Two-dimensional high-entropy sulfides, possessing both rich surface chemical properties and ultra-high conductivity, have become essential core materials for promoting the development of highly efficient water electrolysis catalysts.

[0004] With the deepening research on two-dimensional high-entropy sulfide materials, various preparation methods have been reported. Common high-entropy alloy synthesis methods, such as thermal shock, solvothermal, and cation exchange methods, each have their own advantages, disadvantages, and applicable ranges, and require precise control of reaction parameters (such as temperature, pressure, reaction time, and solvent selection). Furthermore, the synthesis process may encounter problems such as inhomogeneous reactions, impure products, and uneven elemental distribution. Direct sulfidation has attracted widespread research attention due to its simple operation; however, this method requires stringent synthesis conditions, demanding a high-temperature / high-pressure synthesis environment, and is prone to phase / structure separation during preparation. Therefore, the high-throughput controllable preparation of two-dimensional high-entropy sulfides faces significant challenges. In-situ sulfidation using two-dimensional high-entropy hydroxides as templates can effectively avoid the phase / structure separation problems caused by high-temperature sulfidation, further reducing the required sulfidation temperature and enabling efficient, high-throughput synthesis of high-performance two-dimensional high-entropy sulfides. III. Summary of the Invention:

[0005] The technical problem this invention aims to solve is the challenges of existing direct sulfidation methods for producing two-dimensional high-entropy sulfides, including the demanding high-temperature and high-pressure reaction conditions, uneven reaction leading to phase / structure separation, impure products, and uneven elemental distribution. To reduce the difficulty of synthesizing two-dimensional high-entropy sulfides and to controllably prepare high-throughput two-dimensional high-entropy sulfides, this invention provides a method for preparing a highly efficient water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template. Using this invention, the high-efficiency water electrolysis catalyst can effectively reduce the sulfidation temperature and avoid phase / structure separation. In the first step of the high-entropy hydroxide synthesis process, stirring is added to effectively prevent phase separation of different metal elements and promote effective bonding of different elements. Then, using the synthesized high-entropy hydroxide as a template, further in-situ sulfidation is performed to form two-dimensional high-entropy sulfides, thereby improving the material's conductivity and stability.

[0006] To solve the above problems, the technical solution adopted by the present invention is as follows:

[0007] This invention provides a method for controllably preparing a two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template. The preparation method includes the following steps:

[0008] a. Add at least five metal precursors, ammonium fluoride and urea to a polytetrafluoroethylene liner, and add deionized water to form a precursor solution;

[0009] b. The precursor solution obtained in step a is ultrasonically mixed evenly and then transferred to a reaction vessel;

[0010] c. Next, the reaction vessel is placed in an oil bath and stirred. The reaction is carried out at 100-200°C. The product after the reaction is washed and dried to obtain a two-dimensional high-entropy hydroxide.

[0011] d. Take 10-100 mg of the two-dimensional high-entropy hydroxide obtained in step c and place it in the middle of a single-temperature zone tube furnace. Place the crucible containing sulfur powder at the front gas inlet of the tube furnace. The mass ratio between the amount of sulfur powder added and the amount of the two-dimensional high-entropy hydroxide taken is 5-20:1.

[0012] e. Remove impurity gases from the atmosphere of the quartz tube in the tubular furnace by introducing argon gas with a purity of 99.999% at a flow rate of 300-600 sccm to remove other gases in the quartz tube for 10-20 minutes; inert argon gas is continuously introduced as a protective gas during the reaction process.

[0013] f. Once the temperature of the tube furnace reaches 300-400℃, push the sulfur powder from the crucible in and maintain the temperature for 30-60 minutes.

[0014] g. Argon gas is continuously introduced in step e until the temperature drops to room temperature. After the reaction is complete, the argon gas is turned off to obtain the product, a two-dimensional high-entropy sulfide.

[0015] According to the above-described method for controllably preparing a two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the at least five metal precursors in step a are based on four metal salts: FeCl2·4H2O, NiCl2, RuCl3, and MoCl5, and then at least one of the following is added: TaCl5, MnCl2·4H2O, CoCl2, CuCl2, NbCl5, ZnCl2, WCl6, VCl3, Rh(NO3)3, H2PtCl6·6H2O, IrCl3, PdCl2, GrCl3·6H2O, AgNO3, SnCl2·2H2O, SbCl3, and ReCl3; the total amount of all metal precursors added in step a is 0.05–0.15 mmol, and the amount of each metal precursor is the same.

[0016] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the molar ratio of the total amount of all metal precursors, ammonium fluoride, and urea added in step a is 1:1 to 4:1 to 8.

[0017] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the total mass ratio of all metal precursors, ammonium fluoride, and urea to deionized water in step a is 1:20 to 100.

[0018] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the ultrasonic time in step b is 5–15 min.

[0019] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the stirring speed in step c is 400-600 r / min, and the reaction time is 2-10 h.

[0020] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the length of the crucible in step d is 10-15 cm, and the length from the crucible to the constant temperature zone of the tube furnace is 20-25 cm.

[0021] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the argon gas flow rate during the reaction in step e is 50–200 sccm.

[0022] According to the above-described method for preparing a highly efficient two-dimensional high-entropy sulfide electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, the heating rate of the tubular furnace in step f is 1–10 °C / min.

[0023] As can be seen from the above, the technical solution of the present invention has the following steps: First, low-temperature technology is used to assist in the synthesis of two-dimensional high-entropy hydroxides to ensure the effective formation of the high-entropy structure; Second, the two-dimensional high-entropy hydroxides are used as templates for in-situ low-temperature sulfidation to effectively and universally prepare two-dimensional high-entropy sulfides (i.e., by controlling the sulfidation temperature, sulfur powder quality and reaction time to sulfidate the two-dimensional high-entropy hydroxides, thereby effectively synthesizing structurally stable and highly conductive two-dimensional high-entropy sulfides).

[0024] The positive and beneficial effects of this invention are as follows:

[0025] 1. The technical solution of this invention utilizes a two-dimensional high-entropy hydroxide template and synthesizes it through low-temperature technology, which solves the problems of phase separation and segregation of different metal elements in current two-dimensional high-entropy materials, promotes the effective combination of different elements into a high-entropy structure; and uses this template for in-situ sulfidation, successfully preparing 29 kinds of two-dimensional high-entropy sulfides, proving that this method can achieve universal preparation of two-dimensional high-entropy materials.

[0026] 2. Compared with the prior art, the technical solution of this invention uses two-dimensional high-entropy hydroxides as templates and then performs in-situ sulfidation treatment, which can reduce the temperature required for high-entropy sulfides. The sulfidation temperature currently used is below 400℃, avoiding the technical limitations of high temperature and high pressure required for the synthesis of two-dimensional high-entropy sulfides; at the same time, it effectively avoids problems such as phase / structure separation caused by high-temperature sulfidation.

[0027] 3. The preparation method of this invention requires a lower temperature during the reaction process, effectively reducing the difficulty of synthesis. Furthermore, the method has lower equipment requirements, a simple operation process, and requires only two steps, effectively reducing production time and energy consumption. It can also be universally applicable and used for large-scale production of a series of high-performance two-dimensional high-entropy hydroxides and two-dimensional high-entropy sulfides. Therefore, the method of this invention can be considered an ideal method for the industrial production of two-dimensional high-entropy hydroxides and two-dimensional high-entropy sulfides. IV. Description of the attached drawings:

[0028] Figure 1 This invention presents a schematic diagram of an apparatus for the controllable preparation of a two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template; the controllable preparation of two-dimensional high-entropy sulfides is achieved using a two-dimensional high-entropy hydroxide as a template.

[0029] Figure 2 This invention implements all embodiments of the controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalysts based on two-dimensional high-entropy hydroxide templates; that is, a series of two-dimensional high-entropy sulfides prepared by the method of this invention, including 17 pentagonal two-dimensional high-entropy sulfides, 8 hexaagonal two-dimensional high-entropy sulfides, 3 heptagonal two-dimensional high-entropy sulfides, and 1 octagonal two-dimensional high-entropy sulfide.

[0030] Figure 3 SEM image of the pentagonal FeNiRuMoPt-S prepared in Example 1 of this invention;

[0031] Depend on Figure 3 It can be seen that the prepared pentagonal two-dimensional high-entropy sulfide exhibits a two-dimensional nanoflower structure.

[0032] Figure 4 EDS mapping diagram of the pentagonal FeNiRuMoPt-S prepared in Example 1 of this invention;

[0033] Depend on Figure 4 It can be seen that Fe, Ni, Ru, Mo, Pt and S in the prepared pentagonal FeNiRuMoPt-S successfully formed a solid solution phase structure without elemental separation.

[0034] Figure 5 LSV diagram of hydrogen evolution performance of pentagonal FeNiRuMoPt-S prepared in Example 1 of this invention;

[0035] Depend on Figure 5 It can be seen that FeNiRuMoPt-S exhibits excellent hydrogen evolution performance at 10 mA / cm². -2 The overpotential is only 50mV.

[0036] Figure 6The oxygen evolution performance (LSV) of the pentagonal FeNiRuMoPt-S prepared in Example 1 of this invention is shown in Figure 1.

[0037] Depend on Figure 6 It can be seen that FeNiRuMoPt-S exhibits excellent oxygen evolution performance at 10 mA / cm². -2 The overpotential is only 235mV.

[0038] Figure 7 SEM image of the hexa-membered FeNiRuMoCoW-S prepared in Example 2 of this invention;

[0039] Depend on Figure 7 It can be seen that the prepared hexa-element two-dimensional high-entropy sulfide exhibits a two-dimensional nanoflower structure.

[0040] Figure 8 EDS mapping diagram of the hexa-membered FeNiRuMoCoW-S prepared in Example 2 of this invention;

[0041] Depend on Figure 8 It can be seen that Fe, Ni, Ru, Mo, Co, W and S in the prepared hexa-membered FeNiRuMoCoW-S successfully formed a solid solution phase structure without elemental separation.

[0042] Figure 9 LSV diagram of hydrogen evolution performance of the hexa-membered FeNiRuMoCoW-S prepared in Example 2 of this invention;

[0043] Depend on Figure 9 It can be seen that FeNiRuMoCoW-S exhibits excellent hydrogen evolution performance at 10 mA / cm². -2 The overpotential was only 196mV.

[0044] Figure 10 The oxygen evolution performance (LSV) of the hexa-membered FeNiRuMoCoW-S prepared in Example 2 of this invention is shown in the diagram.

[0045] Depend on Figure 10 It can be seen that FeNiRuMoCoW-S exhibits excellent oxygen evolution performance at 10 mA / cm². -2 The overpotential is only 95mV.

[0046] Figure 11 SEM image of the heptagonal FeNiRuMoCoVZn-S prepared in Example 3 of this invention;

[0047] Depend on Figure 11 It can be seen that the prepared heptogenic two-dimensional high-entropy sulfide exhibits a two-dimensional nanoflower structure.

[0048] Figure 12EDS mapping diagram of the heptagonal FeNiRuMoCoVZn-S prepared in Example 3 of this invention;

[0049] Depend on Figure 12 It can be seen that Fe, Ni, Ru, Mo, Co, V, Zn and S in the prepared seven-element FeNiRuMoCoVZn-S successfully formed a solid solution phase structure without elemental separation.

[0050] Figure 13 LSV diagram of hydrogen evolution performance of the heptagonal FeNiRuMoCoVZn-S prepared in Example 3 of this invention;

[0051] Depend on Figure 13 It can be seen that FeNiRuMoCoVZn-S exhibits excellent hydrogen evolution performance at 10 mA / cm². -2 The overpotential is only 173mV.

[0052] Figure 14 The oxygen evolution performance (LSV) of the heptagonal FeNiRuMoCoVZn-S prepared in Example 3 of this invention is shown in Figure 3.

[0053] Depend on Figure 14 It can be seen that the seven-membered FeNiRuMoCoVZn-S exhibits excellent oxygen evolution performance at 10 mA / cm². -2 The overpotential is only 213mV.

[0054] Figure 15 SEM image of the octagonal FeNiRuMoCoVWZn-S prepared in Example 4 of this invention;

[0055] Depend on Figure 15 It can be seen that the prepared octagonal two-dimensional high-entropy sulfide exhibits a two-dimensional nanoflower structure.

[0056] Figure 16 EDS mapping diagram of the octagonal FeNiRuMoCoVWZn-S prepared in Example 4 of this invention;

[0057] Depend on Figure 16 It can be seen that Fe, Ni, Ru, Mo, Co, V, W, Zn and S in the prepared octagonal FeNiRuMoCoVWZn-S successfully formed a solid solution phase structure without elemental separation.

[0058] Figure 17 The hydrogen evolution performance (LSV) of the octagonal FeNiRuMoCoVWZn-S prepared in Example 4 of this invention is shown in Figure 4.

[0059] Depend on Figure 17 It can be seen that FeNiRuMoCoVWZn-S exhibits excellent hydrogen evolution performance at 10 mA / cm².-2 The overpotential is only 235mV.

[0060] Figure 18 The oxygen evolution performance (LSV) of the octagonal FeNiRuMoCoVWZn-S prepared in Example 4 of this invention is shown in Figure 4.

[0061] Depend on Figure 18 It can be seen that FeNiRuMoCoVWZn-S exhibits excellent oxygen evolution performance at 10 mA / cm². -2 The overpotential is only 280mV. V. Detailed Implementation Methods:

[0062] The present invention will be further illustrated below with reference to the embodiments, but this does not limit the scope of protection of the technical solution of the present invention.

[0063] Example 1:

[0064] This invention discloses a method for the efficient synthesis of pentagonal FeNiRuMoPt-S using pentagonal FeNiRuMoPt-OH as a template. The detailed steps are as follows:

[0065] a. Place 19.88 mg of FeCl2·4H2O, 13.25 mg of NiCl2, 20.85 mg of RuCl3, 27.30 mg of MoCl5 and 25.92 mg of H2PtCl6·6H2O powder into a 50 mL polytetrafluoroethylene liner, then add 151.67 mg of urea and 37.04 mg of ammonium fluoride, and then add 30 mL of deionized water to prepare a precursor solution;

[0066] b. Sonicate the precursor solution obtained in step a for 10 minutes to mix it evenly, and then transfer it to the reaction vessel;

[0067] c. Next, the reactor was placed in an oil bath and stirred. During the reaction, the stirring speed was controlled at 477 r / min, the reaction temperature was 150℃, and the reaction time was 6 h. After the reaction was completed, the reactor was frozen and dried in sequence to obtain the five-membered FeNiRuMoPt-OH.

[0068] d. Take 15mg of the five-element FeNiRuMoPt-OH obtained after drying in step c and place it in the middle of a single-temperature zone tube furnace. Place two crucibles containing sulfur powder at the front gas inlet of the tube furnace. The amount of sulfur powder added to each crucible is 640mg. The length of each crucible is 10cm and the length from the crucible to the temperature zone is 25cm.

[0069] e. Remove impurity gases from the atmosphere of the quartz tube in the tubular furnace by introducing argon gas with a purity of 99.999% at a flow rate of 300 sccm to remove other gases in the quartz tube for 10 min. During the reaction, argon gas is continuously introduced as a protective gas. The flow rate of the argon gas used as a protective gas in step e is 100 sccm.

[0070] f. When the temperature of the tube furnace reaches 350℃ (the heating rate is controlled at 5℃ / min during the heating process of the tube furnace), the sulfur powder in the first crucible is pushed in and the temperature is held for 30 minutes; then the sulfur powder in the second crucible is pushed in and the temperature is held for 30 minutes.

[0071] g. After the reaction is complete, argon gas is continuously introduced as described in step e until the temperature drops to room temperature. Then, the argon gas is turned off to obtain the product pentagonal FeNiRuMoPt-S.

[0072] Example 2:

[0073] This invention provides a method for the efficient synthesis of hexa-membered FeNiRuMoCoW-S using hexa-membered FeNiRuMoCoW-OH as a template. The detailed steps are as follows:

[0074] a. Place 19.88 mg of FeCl2·4H2O, 13.25 mg of NiCl2, 20.85 mg of RuCl3, 27.30 mg of MoCl5, 13.25 mg of CoCl2 and 40.05 mg of WCl6 powder into a 50 mL polytetrafluoroethylene liner, then add 151.67 mg of urea and 37.04 mg of ammonium fluoride, and then add 30 mL of deionized water to prepare a precursor solution;

[0075] b. Sonicate the precursor solution obtained in step a for 10 minutes to mix it evenly, and then put it into the reaction vessel;

[0076] c. Next, the reaction vessel was placed in an oil bath and stirred. The stirring speed was 477 r / min, the reaction temperature was 150℃, and the reaction time was 6 h. After the reaction was completed, the vessel was frozen and dried in sequence to obtain the hexa-membered FeNiRuMoCoW-OH.

[0077] d. Take 15mg of the dried hexavalent FeNiRuMoCoW-OH from step c and place it in the middle of a single-temperature zone tube furnace. Place two crucibles containing sulfur powder at the front gas inlet of the tube furnace. The amount of sulfur powder added to each crucible is 640mg. The length of each crucible is 10cm, and the length from the crucible to the temperature zone is 25cm.

[0078] e. Remove impurity gases from the atmosphere of the quartz tube in the tubular furnace by introducing argon gas with a purity of 99.999% at a flow rate of 300 sccm to remove other gases in the quartz tube for 10 min. During the reaction, argon gas is continuously introduced as a protective gas. The flow rate of the argon gas used as a protective gas in step e is 100 sccm.

[0079] f. When the temperature of the tube furnace reaches 350℃ (the heating rate of the tube furnace is 5℃ / min), push the sulfur powder in the first crucible into the furnace and keep it at a constant temperature for 30 minutes; then push the sulfur powder in the second crucible into the furnace and keep it at a constant temperature for 30 minutes.

[0080] g. After the reaction is complete, argon gas is continuously introduced as described in step e until the temperature drops to room temperature. Then, the argon gas is turned off to obtain the product hexa-membered FeNiRuMoCoW-S.

[0081] Example 3:

[0082] This invention provides a method for the efficient synthesis of heptagonal FeNiRuMoCoVZn-S using heptagonal FeNiRuMoCoVZn-OH as a template. The detailed steps are as follows:

[0083] a. Place 19.88 mg of FeCl2·4H2O, 13.25 mg of NiCl2, 20.85 mg of RuCl3, 27.30 mg of MoCl5, 13.25 mg of CoCl2, 16.2 mg of VCl3 and 13.64 mg of ZnCl2 powder into a 50 mL polytetrafluoroethylene liner, then add 151.67 mg of urea and 37.04 mg of ammonium fluoride, and then add 30 mL of deionized water to prepare a precursor solution;

[0084] b. Sonicate the precursor solution obtained in step a for 10 minutes to mix it evenly, and then put it into the reaction vessel;

[0085] c. Next, the reaction vessel was placed in an oil bath and stirred. The stirring speed was 477 r / min, the reaction temperature was 150℃, and the reaction time was 6 h. After the reaction was completed, it was frozen and dried in sequence to obtain the seven-membered FeNiRuMoCoVZn-OH.

[0086] d. Take 15mg of the dried seven-component FeNiRuMoCoVZn-OH from step c and place it in the middle of a single-temperature zone tube furnace. Place two crucibles containing sulfur powder at the front gas inlet of the tube furnace. The amount of sulfur powder added to each crucible is 640mg. The length of each crucible is 10cm, and the length from the crucible to the temperature zone is 25cm.

[0087] e. Remove impurity gases from the atmosphere of the quartz tube in the tubular furnace by introducing argon gas with a purity of 99.999% at a flow rate of 300 sccm to remove other gases in the quartz tube for 10 min. During the reaction, argon gas is continuously introduced as a protective gas. The flow rate of the argon gas used as a protective gas in step e is 100 sccm.

[0088] f. When the temperature of the tube furnace reaches 350℃ (the heating rate during the heating process of the tube furnace is 5℃ / min), push the sulfur powder in the first crucible into the furnace and keep it at a constant temperature for 30 minutes; then push the sulfur powder in the second crucible into the furnace and keep it at a constant temperature for 30 minutes.

[0089] g. After the reaction is complete, argon gas is continuously introduced as described in step e until the temperature drops to room temperature. Then, the argon gas is turned off to obtain the product heptagonal FeNiRuMoCoVZn-S.

[0090] Example 4:

[0091] This invention provides a method for the efficient synthesis of octagonal FeNiRuMoCoVWZn-S using octagonal FeNiRuMoCoVWZn-OH as a template. The detailed steps are as follows:

[0092] a. Place 19.88 mg of FeCl2·4H2O, 13.25 mg of NiCl2, 20.85 mg of RuCl3, 27.30 mg of MoCl5, 13.25 mg of CoCl2, 16.2 mg of VCl3, 13.64 mg of ZnCl2 and 40.05 mg of WCl6 powder into a 50 mL polytetrafluoroethylene liner, then add 151.67 mg of urea and 37.04 mg of ammonium fluoride, and then add 30 mL of deionized water to prepare a precursor solution;

[0093] b. Sonicate the precursor solution obtained in step a for 10 minutes to mix it evenly, and then put it into the reaction vessel;

[0094] c. Next, the reaction vessel was placed in an oil bath and stirred. The stirring speed was 477 r / min, the reaction temperature was 150℃, and the reaction time was 6 h. After the reaction was completed, it was frozen and dried in sequence to obtain the octagonal FeNiRuMoCoVWZn-OH.

[0095] d. Take 15mg of the dried octagonal FeNiRuMoCoVWZn-OH from step c and place it in the middle of a single-temperature zone tube furnace. Place two crucibles containing sulfur powder at the front gas inlet of the tube furnace. The amount of sulfur powder added to each crucible is 640mg. The length of each crucible is 10cm, and the length from the crucible to the temperature zone is 25cm.

[0096] e. Remove impurity gases from the atmosphere of the quartz tube in the tubular furnace by introducing argon gas with a purity of 99.999% at a flow rate of 300 sccm to remove other gases in the quartz tube for 10 min. During the reaction, argon gas is continuously introduced as a protective gas. The flow rate of the argon gas used as a protective gas in step e is 100 sccm.

[0097] f. When the temperature of the tube furnace reaches 350℃ (the heating rate during the heating process of the tube furnace is 5℃ / min), push the sulfur powder in the first crucible into the furnace and keep it at a constant temperature for 30 minutes; then push the sulfur powder in the second crucible into the furnace and keep it at a constant temperature for 30 minutes.

[0098] g. After the reaction is complete, argon gas is continuously introduced as described in step e until the temperature drops to room temperature. Then, the argon gas is turned off to obtain the product octet FeNiRuMoCoVWZn-S.

Claims

1. A method for preparing a two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on a two-dimensional high-entropy hydroxide template, characterized in that, The preparation method comprises the following steps: a. adding at least five metal precursors, ammonium fluoride and urea into a polytetrafluoroethylene liner, and adding deionized water to form a precursor solution; The at least five metal precursors are based on four metal salts of FeCl2·4H2O, NiCl2, RuCl3 and MoCl5, and H2PtCl6·6H2O, or CoCl2 and WCl6, or CoCl2, VCl3 and ZnCl2, or CoCl2, VCl3, ZnCl2 and WCl6 are further added; the total amount of the added substances of all the metal precursors is 0.05-0.15 mmol, and the amounts of substances of the metal precursors are the same; b. uniformly mixing the precursor solution obtained in step a by ultrasonic mixing, and transferring to a reaction kettle; c. then placing the reaction kettle into an oil bath pot for stirring, reacting at 100-200°C, and washing and drying the product after reaction to obtain a two-dimensional high-entropy hydroxide; d. placing 10-100 mg of the two-dimensional high-entropy hydroxide obtained in step c in the middle position of a single-temperature-zone tube furnace, placing a crucible containing sulfur powder in the front end gas inlet position of the tube furnace, and the mass ratio between the added amount of sulfur powder and the two-dimensional high-entropy hydroxide is 5-20:1; e. removing impurity gases in the atmosphere of the quartz tube of the tube furnace, and purging 99.999% pure argon at a flow rate of 300-600 sccm to remove other gases in the quartz tube, and the purging time is 10-20 min; inert argon is continuously purged as a protective gas during the reaction; f. pushing the sulfur powder in the crucible into the tube furnace when the temperature of the tube furnace rises to 300-400°C, and the constant temperature time is 30-60 min; g. continuously purging the argon in step e until the temperature is lowered to room temperature, and the argon is turned off after the reaction is completed to obtain the product two-dimensional high-entropy sulfide.

2. The method for controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The molar ratio of the total amount of all the metal precursors, ammonium fluoride and urea added in step a is 1:1-4:1-8.

3. The method for controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The total amount of all the metal precursors, ammonium fluoride and urea added in step a and the mass ratio of deionized water is 1:20-100.

4. The method for controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The ultrasonic time in step b is 5-15 min.

5. The method for controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The stirring speed in step c is 400-600 r / min, and the reaction time is 2-10 h.

6. The method for controllable preparation of two-dimensional high-entropy sulfide high-efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The length of the crucible in step d is 10-15 cm, and the length from the crucible to the constant temperature zone of the tube furnace is 20-25 cm.

7. The method for controllable preparation of two-dimensional high-entropy sulfide high- efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The purging flow rate of argon in step e during the reaction is 50-200 sccm.

8. The method for controllable preparation of two-dimensional high-entropy sulfide high- efficiency water electrolysis catalyst based on two-dimensional high-entropy hydroxide templates according to claim 1, characterized in that: The heating rate of the temperature of the tube furnace in step f is 1-10°C / min.

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