Second-level ultra-fast preparation method of molybdenum disulfide-based piezoelectric catalytic material and water treatment application method of molybdenum disulfide-based piezoelectric catalytic material

Abstract

According to the method for preparing the molybdenum disulfide-based piezoelectric catalytic material in the second-level ultra-fast mode, the problems of complexity and high cost existing in a traditional method are solved through combination of ultrasonic treatment, rotary evaporation and magnetic induction heating. The method is simple to operate and short in preparation time, and the efficient molybdenum disulfide-based piezoelectric catalytic material can be prepared in a short time. Meanwhile, the material has excellent catalytic performance and stability and can be widely applied to the fields of electro-catalysis hydrogen evolution reaction, water treatment and the like.

Description

[Technical field]

[0001] The present invention relates to a method for preparing a molybdenum disulfide-based piezoelectric catalytic material ultra-fast in seconds, in particular to a method for preparing a molybdenum disulfide-based piezoelectric catalytic material by ultrasonic treatment, rotary evaporation and magnetic induction heating, and an application of the method in water treatment, belonging to the technical fields of material science and environmental engineering. [Background technology]

[0002] Molybdenum disulfide (MoS2) is a layered transition metal disulfide with unique physical and chemical properties. It has broad application prospects in catalysis, optoelectronics, sensing and other fields. Especially in the electrocatalytic hydrogen evolution reaction (HER), MoS2 is considered to be a potential high-efficiency catalyst to replace platinum. In recent years, with the increase in energy demand and the intensification of environmental problems, the development of efficient and low-cost catalytic materials to replace precious metal catalysts has become a research hotspot. MoS2 has attracted widespread attention due to its efficient catalytic performance, stability and abundant resources.

[0003] At present, the preparation methods of MoS2 mainly include hydrothermal / solvothermal method, chemical vapor deposition (CVD) method, liquid phase exfoliation method, etc. These methods have made certain progress in controlling the morphology and performance of the products, but they generally have problems such as complex preparation process, long time consumption, and high cost. In addition, it is difficult to achieve large-scale production during the preparation process, which also limits the promotion of MoS2 in practical applications.

[0004] In order to improve the catalytic performance of MoS2, researchers have introduced a variety of modification methods during the preparation process. For example, by doping different elements (such as nitrogen, phosphorus, etc.) or introducing defect structures, the electrocatalytic performance of MoS2 can be significantly improved. At the same time, compounding MoS2 with conductive materials (such as graphene, carbon nanotubes, etc.) can improve its conductivity and stability, and further improve its catalytic performance. However, these modification methods still face challenges in practical applications, such as complex processes and high costs.

[0005] Magnetic induction heating (MIH) is an emerging heating technology with the advantages of fast heating speed, concentrated energy, and strong controllability. It has been gradually applied to the field of material preparation in recent years. MIH can achieve high-temperature heating in a short time, effectively avoiding the temperature gradient problem caused by heat diffusion in traditional heating methods, thereby achieving precise control of the material microstructure.

[0006] Patent CN201910183384.8 discloses a method for controlling the synthesis of molybdenum disulfide particles in a mixed solvent system, using molybdenum source and sulfur source as reaction raw materials in a hydrothermal system to prepare molybdenum disulfide micro-nano particles; using different types of mixed solvents to achieve effective regulation of the microscopic morphology of molybdenum disulfide particles; controlling the size and dispersion of molybdenum disulfide particles by adding surfactants; using mixed solvents and surfactants to control the synthesis of molybdenum disulfide micro-nano particles. Patent CN201811279544.0 discloses a novel method for synthesizing oil-soluble molybdenum disulfide, using homemade molybdenum trioxide nanobelts as molybdenum source, potassium thiocyanate as sulfur source, hexadecylamine, sodium oleate, etc. as surfactants, and using a solvothermal method to prepare oil-soluble molybdenum disulfide. [Summary of the invention]

[0007] [Technical issues to be solved]

[0008] The purpose of the present invention is to provide a method for preparing molybdenum disulfide-based piezoelectric catalytic materials ultra-fast in seconds. The method is prepared by ultrasonic treatment, rotary evaporation and magnetic induction heating, has simple operation, low cost, short preparation time, and the product has excellent catalytic performance and stability, and can be effectively applied to the field of water treatment.

[0009] [Technical solution]

[0010] A method for preparing a molybdenum disulfide-based piezoelectric catalytic material at ultra-fast speed in seconds and a water treatment application thereof, characterized in that the method comprises the following steps:

[0011] (1) 100 mg of molybdenum pentachloride (MoCl5) and 500 mg of thiourea were dissolved in 10 mL of ethanol and treated with ultrasound for 20 minutes to obtain a transparent solution.

[0012] (2) Add 50 mg of carbon black to the above transparent solution and mix well.

[0013] (3) The mixture was dried by rotary evaporation at 40°C.

[0014] (4) The dried mixture was further dried in a vacuum oven at 60°C for 8 hours.

[0015] (5) The dried material was loaded onto an iron sheet covered with a piece of graphite paper with a thickness of 0.01 mm. The size of the iron sheet was 2.5 cm×2.5 cm×0.2 mm.

[0016] (6) Place the above assembly at the center of the refractory brick in a quartz tube and purge it with high-purity argon gas (flow rate of 100 mL / min) for 10 minutes.

[0017] (7) The quartz tube was placed in a four-turn induction coil with a diameter of 5 cm and subjected to magnetic induction heating for 10 seconds under a controlled current (200 A).

[0018] (8) After magnetic induction heating, the sample was allowed to cool naturally to room temperature to obtain the molybdenum disulfide piezoelectric catalytic material.

[0019] [Beneficial Effects]

[0020] The MoS2-based piezoelectric catalytic material prepared by this method not only exhibits excellent catalytic performance in the electrocatalytic hydrogen evolution reaction, but also shows good results in water treatment applications. This provides new ideas and methods for the promotion of MoS2-based materials in practical applications, and has important research value and application prospects.

Brief Description of the Drawings

[0021] Figure 1 : A transmission electron microscope (TEM) image of the MoS2 piezoelectric catalytic material prepared after Example 1 is shown, showing its microstructure.

[0022] Figure 2 : The Raman spectrum (Raman) of the MoS2 piezoelectric catalytic material prepared after Example 1 is shown, reflecting its chemical composition and structural characteristics.

[0023] Figure 3 : The effect diagram of the MoS2 piezoelectric catalytic material prepared after Example 1 in the degradation of Rhodamine b organic pollutant is shown, indicating its application potential in water treatment. [Specific implementation method]

[0024] Embodiment 1:

[0025] (1) 100 mg of molybdenum pentachloride (MoCl5) and 500 mg of thiourea were dissolved in 10 mL of ethanol and treated with ultrasound for 20 minutes to obtain a transparent solution.

[0026] (2) Add 50 mg of carbon black to the above transparent solution and mix well.

[0027] (3) The mixture was dried by rotary evaporation at 40°C.

[0028] (4) The dried mixture was further dried in a vacuum oven at 60°C for 8 hours.

[0029] (5) The dried material was loaded onto an iron sheet covered with a piece of graphite paper with a thickness of 0.01 mm. The size of the iron sheet was 2.5 cm×2.5 cm×0.2 mm.

[0030] (6) Place the above assembly at the center of the refractory brick in a quartz tube and purge it with high-purity argon gas (flow rate of 100 mL / min) for 10 minutes.

[0031] (7) The quartz tube was placed in a four-turn induction coil with a diameter of 5 cm and subjected to magnetic induction heating for 10 seconds under a controlled current (200 A).

[0032] (8) After magnetic induction heating, the sample was allowed to cool naturally to room temperature to obtain the molybdenum disulfide piezoelectric catalytic material.

[0033] (9) The prepared piezoelectric catalyst material was added to a water sample containing 10 mg / L of organic pollutants such as rhodamine b at a mass concentration of 10 mg / L. The removal rate of the pollutants was measured after ultrasonic treatment for 5 minutes to evaluate the piezoelectric catalytic efficiency of the material. The treatment results are shown in the attached Figure 3 .

[0034] Embodiment 2:

[0035] (1) Take 200 mg of molybdenum pentachloride (MoCl5) and 200 mg of thiourea and dissolve them in 10 mL of ethanol, add 5 wt% of ferric chloride, and treat by ultrasonic for 20 minutes to obtain a transparent solution.

[0036] (2) Add 50 mg of carbon black to the above transparent solution and mix well.

[0037] (3) The mixture was dried by rotary evaporation at 40°C.

[0038] (4) The dried mixture was further dried in a vacuum oven at 60°C for 8 hours.

[0039] (5) The dried material was loaded onto an iron sheet covered with a piece of graphite paper with a thickness of 0.01 mm. The size of the iron sheet was 2.5 cm×2.5 cm×0.2 mm.

[0040] (6) Place the above assembly at the center of the refractory brick in a quartz tube and purge it with high-purity argon gas (flow rate of 100 mL / min) for 10 minutes.

[0041] (7) The quartz tube was placed in a four-turn induction coil with a diameter of 5 cm and subjected to magnetic induction heating for 10 seconds under a controlled current (200 A).

[0042] (8) After magnetic induction heating, the sample was allowed to cool naturally to room temperature to obtain the iron-modified molybdenum disulfide piezoelectric catalytic material.

[0043] (9) The prepared iron-modified molybdenum disulfide piezoelectric catalyst material was added to a water sample containing 10 mg / L of organic pollutants such as rhodamine b at a mass concentration of 10 mg / L. The removal rate of the pollutants was measured after stirring for 30 minutes to evaluate the piezoelectric catalytic efficiency of the material.

Claims

1. A method for preparing a molybdenum disulfide-based piezoelectric catalytic material ultra-fast in seconds, comprising the following steps: (1) dissolving 200 mg to 500 mg of molybdenum pentachloride (MoCl5) and 200 mg to 500 mg of thiourea in 5 mL to 50 mL of ethanol, adding 0-20 wt % of ferric chloride, and treating by ultrasonication to obtain a transparent solution; (2) Add 50 mg to 200 mg of carbon black to the above transparent solution and mix well; (3) drying the mixture by rotary evaporation; (4) the dried mixture is further dried in a vacuum oven at 50° C. to 100° C. for 4 to 12 hours; (6) loading the dried substance onto an iron sheet covered with a graphite paper having a thickness of 0.01 mm to 0.05 mm, wherein the size of the iron sheet is 2 cm to 5 cm×2 cm to 5 cm×0.1 mm to 0.5 mm; (7) placing the above assembly at the center of the refractory brick in a quartz tube and purging with high-purity inert gas for 5 to 30 minutes; (8) placing the quartz tube in a multi-turn induction coil with a diameter of 3 cm to 7 cm and performing magnetic induction heating for 5 seconds to 30 seconds under a controlled current (X = 50 to 800 A); (9) After magnetic induction heating, the sample is allowed to cool naturally to room temperature, and finally a MoS2-based piezoelectric catalytic material is obtained for water treatment applications. (10) The prepared piezoelectric catalyst material was added to a water sample containing organic pollutants at a mass concentration of 10-1000 mg / L. The removal rate of the pollutants was measured after ultrasonic treatment for 1-60 minutes or stirring for 0.1-6 hours to evaluate the piezoelectric catalytic efficiency of the material.

2. The method according to claim 1, wherein the inert gas is argon, nitrogen or helium, and the flow rate of the inert gas is 50 mL / min to 500 mL / min.

3. The method according to claim 1, wherein the frequency of the magnetic induction heating is 50 kHz to 1 MHz, the time of the magnetic induction heating is 5 seconds to 60 seconds, and the power of the induction coil is 1 kW to 10 kW.

4. The method according to claim 1, wherein the conductivity of the graphite paper is 10 S / cm to 1000 S / cm.

5. The method according to claim 1, wherein the molar ratio of molybdenum pentachloride (MoCl5) to thiourea is 1:1 to 1:

3. The method according to claim 1 , wherein the particle size of the carbon black is 20 nm to 100 nm.

7. The method according to claim 1, wherein the surface of the iron sheet is pretreated to improve the adhesion of the graphite paper.

8. The method according to claim 1, wherein the obtained molybdenum disulfide-based piezoelectric catalytic material is used for piezoelectric catalytic degradation of organic matter in water and has high catalytic performance and stability.

9. The method according to claim 1, wherein the molybdenum disulfide-based piezoelectric catalytic material has a morphology of nanosheets or nanowires.

10. The method of claim 1, wherein the molybdenum disulfide-based piezoelectric catalytic material is used in water treatment applications, including but not limited to water purification and sewage treatment.

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