Ruthenium-based alloy-loaded 1T-phase molybdenum disulfide nanosheet, and synthesis process and application thereof

Abstract

The invention discloses a ruthenium-based alloy-loaded 1T-phase molybdenum disulfide nanosheet, a synthesis process and application, and the synthesis process comprises the following steps: (1) dissolving a molybdenum source and a sulfur source in water, and carrying out hydrothermal treatment to obtain a 1T-phase MoS2 nanoflower; (2) dispersing the 1T-phase molybdenum disulfide nanoflowers in an organic solution, carrying out ultrasonic treatment, and then washing and drying to obtain 1T-phase molybdenum disulfide nanosheets; (3) dispersing the 1T-phase molybdenum disulfide nanosheet in water to obtain turbid liquid I; (4) adding a ruthenium source and a transition metal source into the turbid liquid I to obtain turbid liquid II; and (5) mixing the turbid liquid II with a reducing agent, reacting under an ultrasonic condition, and washing and drying after the reaction is finished to obtain the ruthenium-based alloy loaded 1T-phase molybdenum disulfide nanosheet. According to the invention, the production process is simplified, the use of precious metals is reduced, and the production cost is reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalysts, and particularly relates to a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, a synthesis process and an application thereof. Background Art

[0002] As a clean energy source with high energy density and environmental friendliness, hydrogen fuel can effectively alleviate the growing energy demand problem and the environmental pollution problem caused by fossil fuels. Hydrogen production by electrolysis of water is an effective means for sustainable hydrogen production, and a catalyst is required to improve the hydrogen production efficiency. However, currently, noble metals with ultra-low overpotential are generally used as catalysts, but their high cost and scarcity instead increase the production cost of water splitting for hydrogen production.

[0003] Supported catalysts are those in which the active components (usually metals, metal oxides or other active substances) are loaded onto a support, and the support is usually an inorganic material with a large specific surface area and excellent mechanical properties. Supported catalysts are widely used in industrial catalysis because they can effectively reduce the use of noble metals and enhance the efficiency and stability of catalytic reactions.

[0004] Currently, the preparation methods of supported catalysts mainly include sol-gel method, co-precipitation method, electrodeposition method, chemical vapor deposition method and impregnation method. The sol-gel method and the co-precipitation method require heat treatment after mixing the metal precursor with the support, which takes a long time and has a relatively high synthesis temperature. The preparation processes of the electrodeposition method and the chemical vapor deposition method are complex and the cost is high, which is not suitable for large-scale production. The impregnation method is simple to operate, but it depends on a batch reactor, resulting in uneven mixing of chemicals, making it difficult to provide a uniform nucleation and growth environment. At the same time, when using the impregnation method to prepare highly dispersed ultrafine nanocatalysts, a large amount of surfactants and stabilizers often need to be added to prevent nanoparticle aggregation, but these substances will affect the catalytic activity of the material. In addition, the traditional impregnation method has problems such as discontinuous reaction, difficulty in scaling up and low yield.

[0005] In summary, it is necessary to propose a new catalyst and synthesis process to solve the above problems. Summary of the Invention

[0006] To solve the above technical problems, the purpose of the present invention is to provide a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, a synthesis process and an application thereof, which simplifies the production process, reduces the use of noble metals and lowers the production cost.

[0007] To achieve the above invention purpose, the technical solutions adopted by the present invention are as follows:

[0008] In the first aspect of the present invention, a synthesis process of a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy is proposed as follows:

[0009] (1) Dissolve the molybdenum source and sulfur source in water, and obtain 1T-phase MoS 2 nano-flowers after hydrothermal treatment;

[0010] (2) Disperse the 1T-phase molybdenum disulfide nano-flowers in an organic solution, and after ultrasonic treatment, wash and dry to obtain 1T-phase molybdenum disulfide nanosheets, where the organic solution is a dispersant solution;

[0011] (3) Disperse the 1T-phase molybdenum disulfide nanosheets in water to obtain suspension I;

[0012] (4) Add the ruthenium source and transition metal source to suspension I to obtain suspension II;

[0013] (5) Mix suspension II with a reducing agent and react under ultrasonic conditions. After the reaction, wash and dry to obtain 1T-phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy.

[0014] Preferably, in step (1), the hydrothermal treatment temperature is 180-240 °C, and the treatment time is 16-24 h.

[0015] Preferably, in step (1), the molar ratio of the molybdenum source to the sulfur source is 1:(2-5), more preferably 1:(2-4).

[0016] Preferably, in step (1), the molybdenum source includes one or both of sodium molybdate and ammonium molybdate. After the molybdenum source is dissolved in water, the concentration of molybdenum element in water is 0.01-0.05 mol / L.

[0017] Preferably, in step (1), the sulfur source includes one or more of thiourea, L-cysteine, and thioacetamide.

[0018] Preferably, in step (2), the ultrasonic power is 100-1000 W; more preferably, the ultrasonic power is 150-500 W; more preferably, the ultrasonic frequency is 20-40 kHz, and the ultrasonic power is 150-300 W.

[0019] Preferably, in step (2), the organic solution includes one or more of N-methylpyrrolidone, dimethylformamide, and sodium cholate solution.

[0020] Preferably, in step (4), the molar ratio of the ruthenium source to the transition metal source is (1-5):(1-5).

[0021] Preferably, the transition metal source includes one or more of an iron source, a cobalt source, a nickel source, and a copper source.

[0022] Preferably, in step (5), the ultrasonic power is 1-100 W; more preferably, the ultrasonic frequency is 20-60 kHz, and the ultrasonic power is 20-60 W.

[0023] Preferably, in step (5), the reducing agent includes one or more of sodium borohydride, sodium citrate, and hydrazine hydrate.

[0024] Preferably, in step (2), the treatment is carried out in an ultrasonic microreactor.

[0025] In step (5), the reaction is carried out in an ultrasonic microreactor. The flow rate of suspension II into the ultrasonic microreactor after mixing with the reducing agent is 5 - 20 ml / min.

[0026] In the second aspect of the present invention, the present invention provides a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, which includes a carrier and a ruthenium-based alloy. The carrier is a 1T-phase molybdenum disulfide nanosheet.

[0027] Preferably, calculated by mass percentage, the content of the ruthenium-based alloy is 1 - 20 wt%.

[0028] In the third aspect of the present invention, the present invention provides an application of a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy. The 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy is used as a catalyst in the electrolytic water cathode hydrogen evolution production.

[0029] Beneficial effects:

[0030] The present invention uses an ultrasonic microreactor to prepare a novel electrolytic water hydrogen production catalyst. This catalyst uses 1T-phase MoS 2 nanosheets with metalloid properties as a carrier to load a ruthenium-based alloy. The successful loading of the alloy activates the inert basal plane of the 1T-phase MoS 2 nanosheets and improves the catalytic activity of the 1T-phase MoS 2 . In addition, the introduction of transition metal atoms improves the antioxidant ability of ruthenium metal, reduces the cost of the catalyst, and weakens the interaction between ruthenium and hydrogen ions, which is beneficial to the desorption of adsorbed hydrogen.

[0031] The ultrasonic microreactor integrates the microreactor and the acoustic cavitation effect of ultrasonic waves. Compared with the traditional batch reactor, the microreactor realizes rapid mixing of solutions. Due to the acoustic cavitation effect, extreme conditions such as high temperature and high pressure generated when cavitation bubbles in the liquid collapse produce intense shock waves and local flows. This not only improves the reduction ability of the ruthenium-based alloy but also generates more S vacancies on the 1T-phase MoS 2 . In addition, the acoustic cavitation effect also promotes the dispersion of metal particles on the carrier, inhibits the generation of large-sized metal clusters, and improves the utilization efficiency of precious metals. The prepared 1T-phase MoS 2 loaded with small-sized ruthenium-based alloy exhibits catalytic activity similar to that of commercial Pt / C catalysts. Compared with the traditional batch reactor, the process of the present invention can achieve continuous production and large-scale preparation of the catalyst.

[0032] The process flow of the present invention is simple and easy to operate, with less equipment investment and low production cost. The synthesis process of the present invention is easy to scale up and can quickly achieve large-scale production. Description of the Drawings

[0033] Figure 1 The following shows a schematic diagram of the synthesis process of the present invention;

[0034] Figure 2 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 1;

[0035] Figure 3 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 2;

[0036] Figure 4 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 3;

[0037] Figure 5 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 4;

[0038] Figure 6 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 5;

[0039] Figure 7 The following shows the transmission electron microscope photograph and EDX elemental mapping image of Example 6;

[0040] Figure 8 The following shows the electrochemical test graphs of Examples 1-4;

[0041] Figure 9 The following shows the electrochemical test graphs of Examples 4-6;

[0042] Figure 10 The following shows the electrochemical test graphs of Example 4 and Examples 7-10;

[0043] Figure 11 The following shows the electrochemical test graphs of Example 9 and Examples 11-14;

[0044] Figure 12 The following shows the electrochemical test graphs of Example 13 and Examples 15-17;

[0045] Figure 13 The following shows the electrochemical test graphs of Example 13 and Comparative Examples 1-6. Detailed Description of the Invention

[0046] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific embodiments of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can be obtained based on these drawings and other embodiments can be obtained.

[0047] The present invention provides a 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, which includes a carrier and a ruthenium-based alloy. The carrier is a 1T-phase molybdenum disulfide nanosheet. Preferably, calculated by mass percentage, in the 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, the content of the ruthenium-based alloy is 1-20 wt%.

[0048] In the present invention, the size of the 1T-phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy is 100-400 nm.

[0049] As a typical representative of transition metal sulfides, molybdenum disulfide (MoS 2 ) has a two-dimensional layered structure similar to that of graphene. According to the different geometric shapes formed by the different coordinations of Mo atoms and S atoms, MoS 2 produces different crystal phases. Among them, the 1T-phase MoS 2 has metal-like properties and better optoelectronic properties, and can be used as a carrier for hydrogen evolution catalysts. The metal ruthenium (Ru) has a metal-hydrogen (M-H) bond and strength similar to that of platinum (Pt), and its cost is lower than that of metal Pt, making it an effective substitute for Pt. However, the strong interaction between Ru and H * results in slow desorption of H*, which limits the HER performance of the catalyst. The transition metal element M (Fe, Co, Ni) has a weak M-H bond. In the present invention, Ru is combined with the transition metal M to form a RuM alloy and loaded on the 1T-phase MoS 2 . The present invention also provides an improved synthesis process, as shown in Figure 1 and specifically as follows:

[0050] (1) Dissolve the molybdenum source and the sulfur source in water, and obtain 1T-phase MoS 2 nano-flowers after hydrothermal treatment;

[0051] (2) Disperse the 1T-phase molybdenum disulfide nano-flowers in an organic solution, and after ultrasonic treatment, wash and dry to obtain 1T-phase molybdenum disulfide nanosheets with a size of 100-400 nm. Among them, the organic solution is a dispersant solution;

[0052] (3) Disperse the 1T-phase molybdenum disulfide nanosheets in water to obtain suspension I;

[0053] (4) Add the ruthenium source and the transition metal source to suspension I to obtain suspension II;

[0054] (5) Mix the suspension II with a reducing agent and react under ultrasonic conditions. After the reaction, wash and dry to obtain 1T-phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy.

[0055] In step (1), the hydrothermal treatment temperature is 180 - 240 °C, and the treatment time is 16 - 24 h.

[0056] The molybdenum source includes one or both of sodium molybdate and ammonium molybdate. After the molybdenum source is dissolved in water, the concentration of molybdenum element in water is 0.01 - 0.05 mol / L.

[0057] The sulfur source includes one or more of thiourea, L-cysteine, and thioacetamide.

[0058] Preferably, the molar ratio of the molybdenum source to the sulfur source is 1:(2 - 5), more preferably 1:(2 - 4).

[0059] In step (2), the 1T-phase molybdenum disulfide nanoflowers are dispersed in a dispersant organic solution, which is beneficial to obtaining 1T-phase molybdenum disulfide nanosheets with uniform size.

[0060] Preferably, in step (2), the ultrasonic frequency is 20 - 40 kHz, and the ultrasonic power is 150 - 300 W. The ultrasonic conditions have an impact on the yield of 1T-phase molybdenum disulfide nanosheets. When using a lower ultrasonic frequency and / or lower ultrasonic power, the yield of 1T-phase molybdenum disulfide nanosheets decreases.

[0061] Preferably, in step (2), the organic solution includes one or more of N-methylpyrrolidone, dimethylformamide, and sodium cholate solution. More preferably, when the organic solution is sodium cholate solution, the concentration of sodium cholate solution is 0.5 - 3 mg / ml.

[0062] In step (2), the ultrasonic treatment is carried out in an ultrasonic microreactor. It is easy to understand that the present invention does not limit the ultrasonic microreactor. For example, the ultrasonic microreactor can be the Jizi No. 1 of the ultrasonic microreactor product of Moge Microfluidic Technology, with an internal volume of 13.6 mL.

[0063] In the present invention, the 1T-phase MoS 2 nanoflowers prepared in step (1) are first ultrasonically dispersed in a dispersant solution and then in water, which can improve the yield of 1T-phase MoS 2 nanosheets. If the 1T-phase MoS 2 nanoflowers are directly ultrasonically dispersed in water, the yield of 1T-phase MoS 2 nanosheets is less, which is not conducive to subsequent preparation.

[0064] In step (4), the molar ratio of the ruthenium source to the transition metal source is (1 - 5):(1 - 5). The transition metal source includes one or more of an iron source, a cobalt source, a nickel source, and a copper source. During the subsequent reaction process, the ruthenium source and the transition metal source form a ruthenium-based alloy on the surface of the 1T-phase MoS 2 nanosheets.

[0065] In the present invention, the specific type of the transition metal source is not limited. The following are some applicable transition metal sources proposed in the present invention: the ruthenium source includes one or both of ruthenium chloride and ruthenium nitrate; the iron source includes one or both of iron chloride and iron nitrate; the cobalt source includes one or both of iron chloride and iron nitrate; the nickel source includes one or both of nickel chloride and nickel nitrate; the copper source includes one or both of copper chloride and copper nitrate. It is easy to understand that the above-mentioned transition metal sources are chlorides or nitrates because these two transition metal salts are soluble in water, and chloride ions or nitrate radicals are not required in the present invention. Any transition metal source applicable to the synthesis process of the present invention belongs to the transition metal source of the present invention.

[0066] In step (5), the ultrasonic frequency is 20 - 60 kHz, and the ultrasonic power is 20 - 60 W.

[0067] In step (5), the ultrasonic treatment is carried out in an ultrasonic microreactor. It is easy to understand that the present invention places no restrictions on the ultrasonic microreactor. For example, the ultrasonic microreactor can be Mozi-1, a product of Moge Microfluidic Technology, with an internal volume of 0.06 mL.

[0068] In step (5), the reducing agent includes one or more of sodium borohydride, sodium citrate, and hydrazine hydrate. The dosage of the reducing agent is a conventional dosage, and its purpose is to reduce the ruthenium source and the transition metal source to a ruthenium-based alloy.

[0069] In step (5), in the prepared 1T-phase MoS loaded with a ruthenium-based alloy 2 nanosheets, the ruthenium-based alloy includes one or more of ruthenium-iron alloy (RuFe), ruthenium-cobalt alloy (RuCo), ruthenium-nickel alloy (RuNi), and ruthenium-copper alloy (RuCu).

[0070] In step (2), the treatment is carried out in an ultrasonic microreactor; in step (5), the reaction is carried out in an ultrasonic microreactor, and the flow rate of the suspension II entering the ultrasonic microreactor after being mixed with the reducing agent is 5 - 20 ml / min.

[0071] In step (5), in the prepared 1T-phase molybdenum disulfide nanosheets loaded with a ruthenium-based alloy, the ruthenium-based alloy accounts for 1 - 20% of the mass of the 1T-phase molybdenum disulfide nanosheets loaded with the ruthenium-based alloy.

[0072] In step (5), the drying temperature is 50 - 70 °C.

[0073] The technical solution of the present invention will be introduced in detail below with specific embodiments.

[0074] Example 1

[0075] Add 3.5 mmol of thiourea and 1 mmol of ammonium molybdate to a 10 ml beaker, add 50 ml of deionized water, and then stir for 90 min. After that, transfer the solution to an 80 ml Teflon-lined stainless steel autoclave and heat at 180 °C for 24 hours; after cooling to room temperature, collect the product, wash it with deionized water and ethanol and centrifuge 4 times, and place the centrifuged product in a drying oven to dry for 12 h. Grind the obtained solid to obtain 1T-phase MoS 2 nano-flowers.

[0076] Disperse 1 g of 1T-phase MoS 2 nano-flowers in 100 ml of a sodium cholate solution with a concentration of 1.5 mg / ml, and then add it to an ultrasonic microreactor I (ultrasonic frequency: 20 kHz, ultrasonic power: 200 W) for treatment for 1 h. Collect the product, wash it with deionized water and ethanol and centrifuge 4 times, and place the centrifuged product in a drying oven to dry for 12 h. Grind the obtained solid to obtain 1T-phase MoS 2 nano-sheets.

[0077] Disperse 1T-phase MoS 2 nano-sheets in 10 ml of deionized water at a concentration of 5 mg / ml. Then add 0.01 mmol of ruthenium chloride and 0.01 mmol of cobalt chloride, and stir evenly to obtain suspension II.

[0078] Add suspension II and 10 ml of a sodium borohydride solution with a concentration of 1 mg / ml to ultrasonic microreactor II at a flow rate of 5 ml / min, ultrasonic frequency of 20 kHz, and ultrasonic power of 40 W. Collect the product, wash it with deionized water and ethanol and centrifuge 4 times, and place the centrifuged product in a drying oven to dry for 12 h. Grind the obtained solid to obtain 1T-phase MoS 2 nano-sheets loaded with RuCo alloy.

[0079] Observe the transmission electron microscope photos and EDX elemental mapping images of the above-prepared 1T-phase MoS 2 nano-sheets loaded with RuCo alloy material, and the results are as Figure 2 shown. It can be seen from Figure 2 that the prepared RuCo alloy is successfully loaded on the 1T-phase MoS 2 nano-sheets.

[0080] Add 5 mg of the prepared 1T-phase MoS 2The RuCo alloy material supported on nanosheets was added with 950 μL of absolute ethanol solution and 50 μL of 5% Nafion solution, and ultrasonically dispersed for 1 h to obtain a mixed solution; 6 μL of the above solution was pipetted onto a glassy carbon electrode and air-dried at room temperature to obtain a working electrode; a three-electrode system with a saturated calomel electrode as the reference electrode and a graphite rod as the counter electrode was used, and nitrogen was passed for more than 1 h to remove oxygen. Electrochemical tests were carried out in 0.5 M H 2 SO 4 as follows. As Figure 8 shown.

[0081] Example 2

[0082] The difference between this example and Example 1 is that suspension II and 10 ml of a sodium borohydride solution with a concentration of 1 mg / ml were introduced into ultrasonic microreactor II at a flow rate of 10 ml / min. The remaining steps of this example are the same as those of Example 1.

[0083] Figure 3 showed the transmission electron microscope (TEM) images and energy-dispersive X-ray (EDX) elemental mapping images of the 1T-phase MoS 2 nanosheets supported RuCo alloy material prepared in this example.

[0084] Example 3

[0085] The difference between this example and Example 1 is that suspension II and 10 ml of a sodium borohydride solution with a concentration of 1 mg / ml were introduced into ultrasonic microreactor II at a flow rate of 15 ml / min.

[0086] Figure 4 showed the transmission electron microscope (TEM) images and energy-dispersive X-ray (EDX) elemental mapping images of the 1T-phase MoS 2 nanosheets supported RuCo alloy material prepared in this example.

[0087] Example 4

[0088] The difference between this example and Example 1 is that suspension II and 10 ml of a sodium borohydride solution with a concentration of 1 mg / ml were introduced into ultrasonic microreactor II at a flow rate of 20 ml / min.

[0089] Figure 5 showed the transmission electron microscope (TEM) images and energy-dispersive X-ray (EDX) elemental mapping images of the 1T-phase MoS 2 nanosheets supported RuCo alloy material prepared in this example.

[0090] Based on Examples 1-4, it Figure 8 can be seen that the electrochemical performance of the prepared catalyst was tested, and it was found that when the solution was introduced into ultrasonic microreactor II at a flow rate of 20 ml / min, the 1T-phase MoS2 The HER performance of RuCo alloy supported on nanosheets is the best, with an overpotential of -141 mV at a current density of 10 mA·cm -2 .

[0091] The experimental conditions of Examples 1-4 are shown in Table 1 below.

[0092] Table 1 Experimental conditions of Examples 1-4

[0093] Flow rate (ml / min) Ultrasonic power (W) Ru source (mmol) Co source (mmol) Example 1 5 40 0.01 0.01 Example 2 10 40 0.01 0.01 Example 3 15 40 0.01 0.01 Example 4 20 40 0.01 0.01

[0094] Example 5

[0095] The difference between this example and Example 4 is that suspension II and 10 ml of sodium borohydride solution with a concentration of 1 mg / ml were introduced into ultrasonic microreactor II at a flow rate of 20 ml / min. The ultrasonic frequency was 20 kHz and the ultrasonic power was 20 W. The remaining steps of this example are the same as those of Example 4.

[0096] Figure 6 Show the transmission electron microscope photos and EDX element mapping images of the 1T-phase MoS 2 nanosheet-supported RuCo alloy material.

[0097] Example 6

[0098] The difference between this example and Example 4 is that suspension II and 10 ml of sodium borohydride solution with a concentration of 1 mg / ml were introduced into ultrasonic microreactor II at a flow rate of 20 ml / min. The ultrasonic frequency was 20 kHz and the ultrasonic power was 60 W. The remaining steps of this example are the same as those of Example 4.

[0099] Figure 7 Show the transmission electron microscope photos and EDX element mapping images of the 1T-phase MoS 2 nanosheet-supported RuCo alloy material.

[0100] Based on Examples 4-6, the electrochemical performance of the prepared catalysts was tested. It can be seen that when the power of ultrasonic microreactor II is 40 W, the HER performance of the 1T-phase MoS Figure 9 nanosheet-supported RuCo alloy is the best, with an overpotential of -141 mV at a current density of 10 mA·cm 2 . -2 The experimental conditions of Examples 4-6 are shown in Table 2 below.

[0101] Table 2 Experimental conditions of Examples 4-6

[0102] Table 2 Experimental conditions of Examples 4-6

[0103] Flow rate (ml / min) Ultrasonic power (W) Ru source (mmol) Co source (mmol) Example 4 20 40 0.01 0.01 Example 5 20 20 0.01 0.01 Example 6 20 60 0.01 0.01

[0104] Example 7

[0105] The difference between this example and Example 4 is that 1T-phase MoS 2 nano-sheets are dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.02 mmol of ruthenium chloride and 0.02 mmol of cobalt chloride are added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 4.

[0106] Example 8

[0107] The difference between this example and Example 4 is that 1T-phase MoS 2 nano-sheets are dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.03 mmol of ruthenium chloride and 0.03 mmol of cobalt chloride are added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 4.

[0108] Example 9

[0109] The difference between this example and Example 4 is that 1T-phase MoS 2 nano-sheets are dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.04 mmol of ruthenium chloride and 0.04 mmol of cobalt chloride are added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 4.

[0110] Example 10

[0111] The difference between this example and Example 4 is that 1T-phase MoS 2 nano-sheets are dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.05 mmol of ruthenium chloride and 0.05 mmol of cobalt chloride are added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 4.

[0112] Based on Example 4 and Examples 7 - 10, Figure 10 it can be seen that the electro-chemical performance of the prepared catalyst was tested, and it was found that as the input amounts of ruthenium and cobalt increased, the HER performance of 1T-phase MoS 2 nano-sheets loaded with RuCo alloy gradually improved and tended to be stable after the input amount reached 0.04 mmol. Compared with Example 9 with an addition amount of 0.04 mmol, when 0.05 mmol of ruthenium chloride and 0.05 mmol of cobalt chloride were added, there was a slight increase at a current density of 10 mA·cm -2 , and the overpotential was -58 mV. Based on the mass activity comparison, the composition of Example 9 is used for the next ratio optimization.

[0113] The experimental conditions of Example 4 and Examples 7-10 are shown in Table 3 below.

[0114] Table 3 Experimental conditions of Example 4 and Examples 7-10

[0115] Flow rate (ml / min) Ultrasonic power (W) Ru source (mmol) Co source (mmol) Example 4 20 40 0.01 0.01 Example 7 20 40 0.02 0.02 Example 8 20 40 0.03 0.03 Example 9 20 40 0.04 0.04 Example 10 20 40 0.05 0.05

[0116] Example 11

[0117] The difference between this example and Example 9 is that: the 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.02 mmol of ruthenium chloride and 0.06 mmol of cobalt chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 9.

[0118] Example 12

[0119] The difference between this example and Example 9 is that: the 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.027 mmol of ruthenium chloride and 0.053 mmol of cobalt chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 9.

[0120] Example 13

[0121] The difference between this example and Example 9 is that: the 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.053 mmol of ruthenium chloride and 0.027 mmol of cobalt chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 9.

[0122] Example 14

[0123] The difference between this example and Example 9 is that: the 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.06 mmol of ruthenium chloride and 0.02 mmol of cobalt chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 9.

[0124] Based on Example 9 and Examples 11-14, Figure 11 it can be seen that the prepared catalysts were tested for electrochemical performance, and it was found that the input amounts of ruthenium and cobalt in different proportions had a certain influence on the performance of the catalysts. Within the scope of the present invention, the prepared catalysts had good performance. When 0.053 mmol of ruthenium chloride and 0.027 mmol of cobalt chloride were added, the performance of the catalyst was the best, at 10 mA·cm -2The overpotential is -43 mV at a current density of

[0125] The experimental conditions of Example 9 and Examples 11 - 14 are shown in Table 4 below.

[0126] Table 4 Experimental conditions of Example 9 and Examples 11 - 14

[0127] Flow rate (ml / min) Ultrasonic power (W) Ru source (mmol) Co source (mmol) Example 9 20 40 0.04 0.04 Example 11 20 40 0.02 0.06 Example 12 20 40 0.027 0.053 Example 13 20 40 0.053 0.027 Example 14 20 40 0.06 0.02

[0128] Example 15

[0129] The difference between this example and Example 13 is that: 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.053 mmol of ruthenium chloride and 0.027 mmol of iron chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 13.

[0130] Example 16

[0131] The difference between this example and Example 13 is that: 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.053 mmol of ruthenium chloride and 0.027 mmol of nickel chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 13.

[0132] Example 17

[0133] The difference between this example and Example 13 is that: 1T-phase MoS 2 nanosheets were dispersed in 10 ml of deionized water at a concentration of 5 mg / ml. Then 0.053 mmol of ruthenium chloride and 0.027 mmol of copper chloride were added and stirred evenly to obtain suspension II. The remaining steps of this example are the same as those of Example 13.

[0134] Based on Example 13 and Examples 15 - 17, Figure 12 it can be seen that the prepared catalyst was tested for electrochemical performance, and it was found that the catalysts with different Ru-based alloys loaded on 1T-phase MoS 2 nanosheets all achieved good results. Among them, when 0.053 mmol of ruthenium chloride and 0.027 mmol of cobalt chloride were added, the effect was the best, and the overpotential was -43 mV at a current density of 10 mA·cm -2 The overpotential is -43 mV at a current density of

[0135] The experimental conditions of Example 13 and Examples 15 - 17 are shown in Table 5 below.

[0136] Table 5 Experimental conditions of Example 13 and Examples 15 - 17

[0137] Flow rate (ml / min) Ultrasonic power (W) Ru source (mmol) Transition metal source Example 13 20 40 0.053 Cobalt chloride (0.027 mmol) Example 15 20 40 0.053 Iron chloride (0.027 mmol) Example 16 20 40 0.053 Nickel chloride (0.027 mmol) Example 17 20 40 0.053 Copper chloride (0.027 mmol)

[0138] Comparative Example 1

[0139] The difference between this comparative example and Example 13 is that during the preparation process, only the suspension II and 10 ml of a sodium borohydride solution with a concentration of 1 mg / ml were added to the ultrasonic microreactor II, but no ultrasonic treatment was performed, and other steps remained unchanged.

[0140] Comparative Example 2

[0141] The difference between this comparative example and Example 13 is that during the preparation process, cobalt chloride was not added, and other steps remained unchanged.

[0142] Comparative Example 3

[0143] The difference between this comparative example and Example 13 is that during the preparation process, ruthenium chloride was not added, and other steps remained unchanged.

[0144] Comparative Example 4

[0145] The difference between this comparative example and Example 13 is that 1T-phase MoS 2 nanosheets were not prepared, and only the mixed solution of ruthenium chloride and cobalt chloride was reduced to prepare RuCo alloy, and other steps remained unchanged.

[0146] Comparative Example 5

[0147] The difference between this comparative example and Example 13 is that during the preparation process, the suspension II and 10 mg of sodium borohydride were added to a beaker, the total volume of the solution was 10 ml, ultrasonic treatment was performed for 1 min using an ultrasonic probe, and the ultrasonic power was 540 W, and other steps remained unchanged.

[0148] Comparative Example 6

[0149] The difference between this comparative example and Example 13 is that during the preparation process, the suspension II, 10 mg of sodium borohydride, and 10 ml of water were added to a beaker, the total volume of the solution was 20 ml, ultrasonic treatment was performed for 1 min using an ultrasonic probe, and the ultrasonic power was 540 W, and other steps remained unchanged.

[0150] Comparative Example 7

[0151] The difference between this comparative example and Example 13 is that during the preparation of the suspension II, only 1T-phase MoS 2 nanosheets were dispersed in water without adding any metal salts.

[0152] The materials prepared in Comparative Examples 1-6 were subjected to electrochemical tests. As Figure 13 shown. By Figure 13It can be seen that the catalyst with ruthenium-based alloy supported on 1T-phase MoS nanosheets prepared using an ultrasonic microreactor has the best HER performance. 2 The catalysts with ruthenium-based alloy supported on 1T-phase MoS nanosheets prepared using an ultrasonic microreactor have the best HER performance.

[0153] X-ray photoelectron spectroscopy (XPS) experiments were carried out on the catalyst of Example 13, Comparative Example 1, Comparative Example 7 and 1T-phase MoS nanosheets, and the atomic ratios of different materials were obtained, as shown in Table 6. It can be obtained from Table 6 that the ratio of Ru atoms to Co atoms in Example 13 is higher than that in Comparative Example 1, which indicates that ultrasound can improve the reduction ability of Ru metal in the ultrasonic microreactor. According to the XPS results of Comparative Example 7 and 1T-phase MoS nanosheets, it is found that the ratio of S atoms to Mo atoms in Comparative Example 7 is lower than that of 1T-phase MoS nanosheets. 2 X-ray photoelectron spectroscopy (XPS) experiments were carried out on the catalyst of Example 13, Comparative Example 1, Comparative Example 7 and 1T-phase MoS nanosheets, and the atomic ratios of different materials were obtained, as shown in Table 6. It can be obtained from Table 6 that the ratio of Ru atoms to Co atoms in Example 13 is higher than that in Comparative Example 1, which indicates that ultrasound can improve the reduction ability of Ru metal in the ultrasonic microreactor. According to the XPS results of Comparative Example 7 and 1T-phase MoS nanosheets, it is found that the ratio of S atoms to Mo atoms in Comparative Example 7 is lower than that of 1T-phase MoS nanosheets. 2 nanosheets. This shows that the 1T-phase MoS2 nanosheets can increase the concentration of S vacancies after being treated by the ultrasonic microreactor II. 2 nanosheets. This shows that the 1T-phase MoS2 nanosheets can increase the concentration of S vacancies after being treated by the ultrasonic microreactor II.

[0154] In summary, the ultrasonic microreactor technology has shown a significant performance improvement in the catalyst preparation process, and its unique process mechanism plays a key role in optimizing the structure and performance of materials. On the one hand, the high-frequency vibration and cavitation effect generated by ultrasonic waves in the microreactor can effectively break the aggregates between molecules, and promote the formation of S vacancies on the catalyst surface through strong microjets and local high-temperature and high-pressure environments. These S vacancies, as active sites, not only improve the binding ability between the catalyst and reactant molecules, but also accelerate the electron transfer in the reaction process, thus significantly enhancing the hydrogen evolution reaction (HER) activity of the material. On the other hand, the reducing environment of ultrasonic waves can enhance the reduction rate of metal ions, enabling Ru atoms to be evenly distributed on the surface of the support and further reducing the overpotential of the catalyst. Through these synergistic effects, the HER performance of this material not only rivals that of commercial Pt / C catalysts, but even surpasses it in some aspects.

[0155] In addition, the ultrasonic microreactor technology adopted in the present invention has many unique advantages in terms of process. Its reaction space is small and the energy is concentrated, making the reaction conditions more controllable, while avoiding the side reactions and non-uniformity problems that are prone to occur in traditional large-scale reactions. The ultrasonic microreactor also has the ability of continuous manufacturing, which means that real-time regulation can be achieved during the material synthesis process, effectively improving the production efficiency and the stability of product quality. At the same time, this technology is easy to scale up, breaking through the bottleneck between laboratory synthesis and industrial application. Compared with traditional catalyst preparation methods, this process shows excellent potential in energy-saving, high-efficiency and green preparation, providing strong technical support for the industrial production of low-cost and high-performance catalysts in the future.

[0156] Table 6 Example 13, Comparative Example 1, Comparative Example 7 and 1T-phase MoS 2XPS data of nanosheets

[0157] Ru Co Mo S Example 13 14.86 9.39 28.18 47.57 Comparative Example 1 2.55 5.64 35.84 55.97 Comparative Example 7 -- -- 16.4 29.5 1T-phase MoS2 nanosheets -- -- 19.62 32.71

[0158] The above has elaborated in detail on the embodiments provided by the present invention. Specific examples are used herein to elaborate on the principles and implementation manners of the present invention. The description of the above embodiments is only used to help understand the core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principles of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy, characterized in that: as follows: (1) dissolving a molybdenum source and a sulfur source in water, and obtaining 1T phase MoS2 nanoflowers after hydrothermal treatment; (2) dispersing the 1T phase MoS2 nanoflowers in an organic solution, subjecting the mixture to ultrasonic treatment, and then washing and drying the mixture to obtain 1T phase MoS2 nanosheets, wherein the organic solution is a dispersant solution; (3) dispersing 1T phase MoS2 nanosheets in water to obtain suspension I; (4) adding a ruthenium source and a transition metal source to the suspension I to obtain a suspension II; (5) The suspension II is mixed with a reducing agent and reacted under ultrasonic conditions. After the reaction is completed, the suspension is washed and dried to obtain 1T phase MoS2 nanosheets loaded with ruthenium-based alloy.

2. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to claim 1, characterized in that: In step (2), the treatment is carried out in an ultrasonic microreactor; In step (5), the reaction is carried out in an ultrasonic microreactor, and the flow rate of the suspension II and the reducing agent entering the ultrasonic microreactor after mixing is 5 to 20 ml / min.

3. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to claim 2, characterized in that: In step (5), the ultrasonic frequency is 20 to 60 kHz, and the ultrasonic power is 1 to 100 W; Preferably, the ultrasonic power is 20-60W.

4. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to claim 2, characterized in that: In step (2), the ultrasonic frequency is 20 to 40 kHz, and the ultrasonic power is 10 to 1000 W; Preferably, the ultrasonic power is 150-500W.

5. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to any one of claims 1 to 4, characterized in that: In step (1), the molar ratio of the molybdenum source to the sulfur source is 1:(2-5); Preferably, the molar ratio of the molybdenum source to the sulfur source is 1:(2-4).

6. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to claim 5, characterized in that: In step (1), the molybdenum source includes one or both of sodium molybdate and ammonium molybdate, and after the molybdenum source is dissolved in water, the concentration of the molybdenum element in the water is 0.01 to 0.05 mol / L; The sulfur source includes one or more of thiourea, L-cysteine ​​and thioacetamide.

7. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to any one of claims 1 to 4, characterized in that: In step (4), the molar ratio of the ruthenium source to the transition metal source is (1-5):(1-5).

8. The synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy according to claim 7, characterized in that: The transition metal source includes one or more of an iron source, a cobalt source, a nickel source, and a copper source.

9. A 1T phase molybdenum disulfide nanosheet loaded with a ruthenium-based alloy, characterized in that: The invention is prepared by the synthesis process of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy as described in any one of claims 1 to 8, comprising a carrier and a ruthenium-based alloy, wherein the carrier is a 1T phase molybdenum disulfide nanosheet.

10. An application of 1T phase molybdenum disulfide nanosheets loaded with ruthenium-based alloy, characterized in that: The 1T phase molybdenum disulfide nanosheet loaded with ruthenium-based alloy prepared by the synthesis process described in any one of claims 1 to 8 is used as a catalyst in the production of cathode hydrogen evolution in water electrolysis.

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