A type of WO 2.72 Preparation methods of ZnS photocatalytic composite materials and their application in photocatalytic hydrogen production

Abstract

This invention discloses a WO 2.72 Preparation method of ZnS photocatalytic composite material and its application in photocatalytic hydrogen production. 2.72 The preparation method of the ZnS photocatalytic composite material includes the following steps: synthesizing ZnS and WO3 separately using a hydrothermal method. 2.72 The obtained ZnS and WO 2.72 Add to anhydrous ethanol, stir for 2–6 hours, filter, wash, and dry to obtain WO3. 2.72 / ZnS photocatalytic composite material. The catalyst obtained in this invention exhibits excellent catalytic performance in photocatalytic hydrogen production. Under xenon lamp irradiation with a current of 20A, in an aqueous solution of lactic acid, the hydrogen production rate reached 1132 μmol / g / h after continuous irradiation for 1 hour.

Description

A type of WO 2.72 Preparation methods of ZnS photocatalytic composite materials and their application in photocatalytic hydrogen production Technical Field

[0001] This invention belongs to the field of photocatalytic materials, and specifically relates to a WO3-O4 ...5-O4-O4-O4-O 2.72 Preparation methods of ZnS photocatalytic composite materials and their application in photocatalytic hydrogen production Background Technology

[0002] Currently, the energy use situation in human society presents a diversified trend, with the following main characteristics: 1. Diversified energy structure: Traditional fossil fuels still dominate: Oil, natural gas, and coal remain the main global energy sources, accounting for approximately 80% of total energy consumption. Oil is mainly used for transportation, while coal is mainly used for power generation and industrial production. 2. Continuously growing energy consumption: Global energy demand is rising: With population growth and economic development, global energy demand is constantly increasing. Developing countries, in particular, such as India, are experiencing a significant increase in energy consumption. 3. Energy transition and decarbonization: Carbon reduction targets and policies: To address climate change, many countries and regions worldwide have proposed carbon neutrality targets and are actively promoting the development and application of low-carbon energy technologies, such as electric vehicles, hydrogen energy, and carbon capture technology. Photocatalysis is a process that uses light energy to excite a catalyst to produce a chemical reaction. Its main mechanism is that the photocatalyst absorbs light energy, generating electron-hole pairs. These electrons and holes can react with surrounding chemical substances, thereby triggering a series of redox reactions. Photocatalysis technology has received widespread attention due to its high efficiency, environmental friendliness, and ability to utilize light energy for reactions.

[0003] Zinc sulfide (ZnS) photocatalysts are important semiconductor materials that have attracted widespread attention in the field of photocatalysis due to their unique physical and chemical properties. Advantages: High photocatalytic activity: ZnS exhibits high photocatalytic activity, especially under ultraviolet light irradiation. Chemical stability: ZnS demonstrates good chemical stability under both acidic and alkaline conditions. Environmental friendliness: ZnS is non-toxic and pollution-free, making it an environmentally friendly photocatalytic material. It has various applications in photocatalysis, such as: Water splitting for hydrogen production: ZnS, as a photocatalyst, can split water into hydrogen and oxygen, providing a clean method for hydrogen production. Degradation of organic pollutants: ZnS can degrade organic pollutants, such as dyes and pesticides, purifying water bodies and the environment. Air purification: ZnS can be used to remove harmful substances from the air, such as volatile organic compounds (VOCs). 2.72 It is an important photocatalyst, exhibiting outstanding performance in the field of photocatalysis due to its unique structure and optical properties. Its advantages include: high photocatalytic activity: WO3 2.72It exhibits high photocatalytic activity, especially demonstrating excellent performance under visible light. Good light response: its wide photogap and oxygen-deficient structure enable it to effectively respond to ultraviolet and some visible light. Strong chemical stability: WO3 2.72 It exhibits high chemical stability under various environmental conditions and is not easily corroded by light.

[0004] Photocatalytic hydrogen production is an environmentally friendly and sustainable method that does not rely on fossil fuels; it directly utilizes sunlight to split water, and is expected to achieve large-scale, low-cost hydrogen production. Summary of the Invention

[0005] The purpose of this invention is to provide a WO4 with high catalytic efficiency. 2.72 Preparation method of / ZnS photocatalytic material.

[0006] The technical solution adopted in this invention is: a WO 2.72 The preparation method of / ZnS photocatalytic composite material includes the following steps:

[0007] 1) ZnS and WO3 were synthesized separately using a hydrothermal method. 2.72 ;

[0008] 2) Combine the ZnS and WO obtained in step 1). 2.72 Add to anhydrous ethanol, stir for 2–6 hours, filter, and wash.

[0009] WO3 obtained by drying 2.72 / ZnS photocatalytic composite material.

[0010] The above-described preparation method, wherein the WO 2.72 The preparation method includes the following steps: stirring tungsten source and anhydrous ethanol evenly, carrying out a hydrothermal reaction, cooling down, centrifuging and washing, and drying to obtain WO3. 2.72 .

[0011] In the above preparation method, the hydrothermal reaction is carried out at 180°C for 24 hours.

[0012] In the above preparation method, the tungsten source is tungsten chloride.

[0013] The ZnS preparation method described above includes the following steps: mixing zinc salt and sulfur source with water and stirring until homogeneous; transferring the mixture to a reaction vessel for hydrothermal reaction; cooling, centrifuging, washing, and drying to obtain ZnS.

[0014] In the above preparation method, the sulfur source used is thiourea, and the zinc salt is zinc acetate dihydrate.

[0015] In the above preparation method, the molar ratio of zinc salt to sulfur source is 1:2.

[0016] In the above preparation method, the hydrothermal reaction is carried out at 200°C for 4-8 hours.

[0017] WO prepared by the above method 2.72 Application of ZnS photocatalytic materials in photocatalytic hydrogen production.

[0018] The above application is performed using the following method: a photocatalytic sealed reaction tank is used as the reactor, lactic acid aqueous solution is used as the reaction medium, a xenon lamp is used as the light source, and simulated sunlight is used as the radiation light. 2.72 / ZnS is used as a catalyst for photocatalytic hydrogen production.

[0019] Preferably, in the above application, lactic acid is used as a hole sacrificial agent and the xenon lamp current is 20A.

[0020] The beneficial effects of this invention are: this invention uses a green and simple hydrothermal method and a simple impregnation method to prepare WO3. 2.72 / ZnS composite catalyst. The WO3 provided by this invention 2.72 ZnS photocatalytic material exhibits high catalytic efficiency and rapid reaction. Under xenon lamp irradiation with a current of 20A, in an aqueous solution of lactic acid, the hydrogen generation rate reached 1132 μmol / g / h after 1 hour of continuous illumination. Attached Figure Description

[0021] Figure 1 is a transmission electron microscope image of the ZnS photocatalytic material.

[0022] Figure 2 is WO 2.72 Transmission electron microscope image of photocatalytic materials.

[0023] Figure 3 is WO 2.72 Transmission electron microscopy image of the ZnS photocatalytic composite material.

[0024] Figure 4 is WO 2.72 X-ray diffraction (XRD) pattern of ZnS4 photocatalytic material.

[0025] Figure 5 is WO 2.72 X-ray diffraction (XRD) pattern of photocatalytic materials.

[0026] Figure 6 is WO 2.72 Solid-state UV absorption diagram of ZnS4 photocatalyst material.

[0027] Figure 7 is WO 2.72 / Photocatalytic hydrogen production performance of ZnS4 photocatalytic material. Detailed Implementation

[0028] To better understand the technical solution of the present invention, specific embodiments are provided for further explanation, but the solution is not limited thereto.

[0029] Example 1 WO2.72 The preparation method of ZnS photocatalytic material (I) is as follows:

[0030] 1. Preparation of ZnS:

[0031] Add 6 mmol of zinc acetate dihydrate and 12 mmol of thiourea to a beaker, add water and mix, then stir for 2-3 hours until homogeneous. Transfer the mixture to a reaction vessel, hydrothermally heat at 200°C for 5 hours, cool, centrifuge, wash, and dry at 80°C overnight.

[0032] 2. WO 2.72 Preparation:

[0033] Add 150 mg of tungsten chloride and 10 mL of anhydrous ethanol to the liner of the reactor and stir well. React hydrothermally at 180 °C for 24 hours, cool down, centrifuge and wash, and vacuum dry at 60 °C overnight.

[0034] 3. WO 2.72 Preparation of ZnS catalyst

[0035] Weigh out 0.05 mg WO 2.72 50 mg ZnS was added to 30 mL of anhydrous ethanol, stirred at room temperature for 5 hours, filtered, washed, and dried under vacuum at 60 °C overnight to obtain the composite catalyst.

[0036] (II) Testing

[0037] 1. Figures 1 and 2 show the prepared ZnS and WO3. 2.72 Transmission electron microscopy (TEM) images of the photocatalytic materials, as shown in Figures 1 and 2, reveal that the prepared ZnS is aggregated into particles; while WO... 2.72 It then displays spherical spines similar to those of a sea urchin.

[0038] 2. Figure 3 shows the prepared WO3. 2.72 The transmission electron microscope (TEM) image of the / ZnS photocatalytic material, as shown in Figure 3, reveals that the prepared catalyst exhibits both aggregated granular morphology of zinc sulfide and urchin-like morphology of blue tungsten trioxide, indicating the successful preparation of the composite material.

[0039] 3. Figure 4 shows the prepared WO3. 2.72 The X-ray diffraction (XRD) pattern of the ZnS photocatalytic material, as shown in Figure 4, shows that no WO3-related material was observed. 2.72 The characteristic peaks of the composite material were observed, but both ZnS and WO were observed in the transmission electron microscopy image of the composite material (Figure 3). 2.72 Therefore, no WO-related entries appeared. 2.72 The characteristic peaks may be due to WO 2.72 The amount added is small, and it is too dispersed on ZnS.

[0040] 4. Figure 5 shows the prepared WO3. 2.72 The XRD pattern shows that the peaks of the prepared catalyst correspond well with those of the standard card, indicating that WO3... 2.72 Successful preparation.

[0041] 5. Figure 6 shows the prepared WO3. 2.72 The solid-state UV absorption spectrum of ZnS shows that WO3 is loaded onto ZnS. 2.72 Subsequently, its absorbance in the long-wavelength direction increased significantly, and the absorption band edge also shifted. This also reflects the reason for the improved catalyst performance.

[0042] Example 2 WO 2.72 Application of ZnS photocatalytic materials in photocatalytic hydrogen production.

[0043] Xenon lamps from Zhongjiao Jinyuan were used to test the photocatalytic hydrogen production performance of the catalyst.

[0044] The method is as follows: A photocatalytic sealed reaction tank is used as the reactor. Before the reaction, inert gas is used to exhaust the gas. Lactic acid aqueous solution is used as the reaction medium, a xenon lamp is used as the light source, simulated sunlight is used as the radiation light, and the prepared WO3 is used as the reaction medium. 2.72 ZnS, WO 2.72 / ZnS was used as a catalyst for photocatalytic hydrogen production, and the products were detected by gas chromatography.

[0045] Figure 7 shows WO 2.72 The image shows the photocatalytic hydrogen production effect of the ZnS photocatalytic material. As can be seen from the image, when the two are combined, the hydrogen production rate of the catalyst increases by nearly 2 times, reaching 1132 μmol / g / h. This indicates that WO3... 2.72 The addition of WO3 helps improve the photocatalytic hydrogen production performance of ZnS. This is because modifying ZnS with a small amount of WO3... 2.72 Subsequently, the absorbance of the composite material increased, allowing it to absorb more light and generate more photogenerated carriers. These carriers can then participate in the reaction, thereby improving photocatalytic performance and increasing hydrogen production.

Claims

1. A type of WO 2.72 The application of ZnS photocatalytic composite materials in photocatalytic hydrogen production is characterized by... The method is as follows: a photocatalytic sealed reaction tank is used as the reactor, lactic acid aqueous solution is used as the reaction medium, a xenon lamp is used as the light source, and simulated sunlight is used as the radiation light. 2.72 / ZnS is used as a catalyst for photocatalytic hydrogen production; the WO 2.72 The preparation method of ZnS photocatalytic composite material includes the following steps: 1) ZnS and WO3 are synthesized separately by hydrothermal method. 2.72 The ZnS preparation method includes the following steps: Zinc acetate dihydrate and thiourea are mixed with water at a molar ratio of 1:2 and stirred until homogeneous. The mixture is then transferred to a reaction vessel for hydrothermal reaction at 200°C for 4-8 hours. After cooling, centrifugation, washing, and drying, ZnS is obtained. The WO3... 2.72 The preparation method includes the following steps: tungsten chloride and anhydrous ethanol are stirred evenly, hydrothermally reacted at 180℃ for 24 hours, cooled, centrifuged, washed, and dried to obtain WO3. 2.72 ;2) Take the 50mg ZnS and 0.05mg WO obtained in step 1) 2.72 Add to anhydrous ethanol, stir for 2-6 hours, filter, wash, and dry to obtain WO3. 2.72 / ZnS photocatalytic composite material.

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