Preparation method and application of cadmium sulfide in-situ polymerized maleic anhydride photocatalytic material
By in-situ polymerization of maleic anhydride on cadmium sulfide, a cadmium sulfide/maleic anhydride photocatalytic material was prepared, which solved the problems of photocorrosion of single CdS and low separation efficiency of photogenerated carriers, and achieved high efficiency and stability of photocatalytic performance, which is suitable for photocatalytic degradation of organic dyes.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SOUTH CHINA NORMAL UNIV
- Filing Date
- 2023-12-07
- Publication Date
- 2026-07-24
AI Technical Summary
Single CdS photocatalytic materials suffer from severe photocorrosion and poor photogenerated carrier separation efficiency, which affects the improvement of their photocatalytic activity.
A one-step photochemical synthesis method at room temperature was adopted to prepare cadmium sulfide/maleic anhydride photocatalytic materials using photoinitiated polymerization technology and low-power ultraviolet lamps. By in-situ polymerization of maleic anhydride on cadmium sulfide, the specific surface area was increased and the internal structure was controlled, thereby improving the separation efficiency of photogenerated electron-hole pairs.
The catalytic efficiency of single CdS is improved. The material exhibits strong degradation performance of organic dyes under visible light, and has good stability and repeatability, making it suitable for mass production.
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Figure CN117680197B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of photocatalysis technology, specifically relating to a method for preparing and applying a photocatalytic material for in-situ polymerization of cadmium sulfide maleic anhydride. Background Technology
[0002] CdS is an excellent semiconductor photocatalytic material with a suitable band gap and strong visible light absorption, exhibiting highly efficient photocatalytic performance under visible light and possessing significant research and application value in the field of photocatalysis. In recent years, with the rapid development of photocatalytic materials research, CdS has received increasing attention as an important catalytic material for the visible light degradation of dyes. However, CdS itself suffers from severe photocorrosion and poor photogenerated carrier separation efficiency, which seriously affects its further improvement in photocatalytic activity. Therefore, it is necessary to modify CdS to overcome its severe photocorrosion problem and better enable its application in photocatalysis. Summary of the Invention
[0003] To overcome the shortcomings of the prior art, this invention employs a one-step photochemical synthesis method at room temperature, utilizing photoinitiated polymerization technology and low-power ultraviolet lamps to prepare a cadmium sulfide / maleic anhydride photocatalytic material. This overcomes the severe photocorrosion phenomenon of single CdS, enabling it to be better applied in photocatalysis.
[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:
[0005] The first aspect of this invention provides a method for preparing a cadmium sulfide / maleic anhydride photocatalytic material, comprising the following steps:
[0006] S1. Dissolve the sulfur source and cadmium source in water, and dissolve the monomer maleic anhydride in an organic solvent, then combine the two solutions;
[0007] S2. Under stirring, the mixed solution from step S1 is placed under ultraviolet light and photopolymerized to obtain cadmium sulfide / maleic anhydride photocatalytic material.
[0008] This invention provides a method for preparing cadmium sulfide-based maleic anhydride photocatalytic materials through in-situ polymerization. This method employs a one-step photochemical synthesis at room temperature, utilizing photoinitiated polymerization technology and a low-power ultraviolet lamp. No external initiator is required, the conditions are mild and environmentally friendly, and the operation is simple and safe. The resulting catalytic material has an increased specific surface area, a greater chance of developing complexation centers, and its internal structure is also regulated by carboxyl groups. The separation efficiency of photogenerated electron-hole pairs is improved, thereby effectively enhancing the catalytic efficiency of single CdS.
[0009] Preferably, in step S1, the sulfur source includes (but is not limited to) sodium thiosulfate, and the cadmium source includes (but is not limited to) cadmium sulfate.
[0010] Preferably, in step S1, the molar ratio of the sulfur source to the cadmium source is 4-5:1. More preferably, the molar ratio of the sulfur source to the cadmium source is 4.5:1.
[0011] Preferably, in step S1, the volume ratio of water to organic solvent is 100:6.25-200. More preferably, the volume ratio of water to organic solvent is 4:1.
[0012] Preferably, in step S1, the concentration of maleic anhydride in the organic solvent is 0.2g / 6.25-200mL.
[0013] Preferably, in step S2, when dissolving the monomeric maleic anhydride in the organic solvent, a dispersant is also added, wherein the ratio of the dispersant to maleic anhydride is 6:1-5. The presence of the dispersant can make the degradation process more stable.
[0014] Preferably, in step S2, the ultraviolet irradiation involves placing two low-power ultraviolet lamps above the solution. The ultraviolet lamps have a specification of 254nm and 8W, and the irradiation time is no less than 24 hours.
[0015] Preferably, in step S1, the organic solvent includes (but is not limited to) ethanol.
[0016] Preferably, in step S2, the stirring speed is 200-300 r / min.
[0017] The second aspect of the present invention provides a cadmium sulfide / maleic anhydride photocatalytic material prepared by the preparation method described in the first aspect.
[0018] The third aspect of this invention provides the application of the cadmium sulfide / maleic anhydride photocatalytic material described in the second aspect in the photocatalytic degradation of organic dyes.
[0019] Preferably, the organic dye includes (but is not limited to) rhodamine B.
[0020] The fourth aspect of the present invention provides a method for photocatalytic degradation of organic dyes, specifically: adding the cadmium sulfide / maleic anhydride photocatalytic material described in the second aspect to a solution containing organic dyes, dispersing it evenly by ultrasonication, and then subjecting it to blue light degradation for no less than 1 hour.
[0021] Compared with the prior art, the beneficial effects of the present invention are:
[0022] This invention discloses a method for preparing a cadmium sulfide / maleic anhydride photocatalytic material. The method uses a sulfur source, a cadmium source, and maleic anhydride monomer as raw materials, and polymerizes maleic anhydride in situ on cadmium sulfide under ultraviolet light initiation. The resulting cadmium sulfide / maleic anhydride photocatalytic material exhibits strong degradation performance of organic dyes under visible light, and also demonstrates excellent stability and reproducibility. Furthermore, the preparation method of this invention is simple, can be prepared at room temperature, requires no external initiator, and is mild and environmentally friendly, making it easily mass-producible. The synthesized cadmium sulfide / maleic anhydride photocatalytic material overcomes the limitations of poor photocatalytic performance of single CdS, and has extremely broad application prospects in the degradation of polluting dyes. Attached Figure Description
[0023] Figure 1 A scanning electron microscope image of a single CdS material;
[0024] Figure 2 Scanning electron microscope image of maleic anhydride material produced by in-situ polymerization of cadmium sulfide;
[0025] Figure 3 Performance graphs of catalytic materials synthesized by different methods (solvothermal method, photopolymerization method);
[0026] Figure 4 Performance chart of in-situ polymerized maleic anhydride photocatalyst (with and without dispersant);
[0027] Figure 5 Performance graphs of in-situ polymerized maleic anhydride photocatalysts (with different monomer amounts);
[0028] Figure 6 Performance graphs of in-situ polymerized maleic anhydride photocatalysts (with different water-to-alcohol ratios);
[0029] Figure 7 The repeated test performance graph of the in-situ polymerized maleic anhydride photocatalyst material of cadmium sulfide;
[0030] Figure 8 The image shows the stability test performance of the in-situ polymerized maleic anhydride photocatalyst material made from cadmium sulfide. Detailed Implementation
[0031] The specific embodiments of the present invention will be further described below. It should be noted that these descriptions are for the purpose of aiding understanding the present invention, but do not constitute a limitation thereof. Furthermore, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.
[0032] Unless otherwise specified, the experimental methods used in the following embodiments are conventional methods, and the experimental materials used in the following embodiments are all available through conventional commercial channels.
[0033] Example 1: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0034] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer was uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and mixed evenly. The mixture was then placed in a 125 mm crystallizing dish, and two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution. The solution was stirred at a speed of 220 r / min for 24 h to obtain a pale yellow solution. The pale yellow particles were then collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0035] Example 2: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0036] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0037] Example 3: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0038] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.1 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0039] Example 4: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0040] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.3 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0041] Example 5: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0042] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.4 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0043] Example 6: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0044] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.5 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0045] Example 7: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0046] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 6.25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0047] Example 8: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0048] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 20 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0049] Example 9: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0050] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 33.3 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0051] Example 10: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0052] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 50 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0053] Example 11: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0054] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 100 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0055] Example 12: Preparation of in-situ polymerized maleic anhydride photocatalyst material by photopolymerization method
[0056] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 200 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and placed in a 125 mm crystallizing dish. Two low-power UV lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm above the solution, and the solution was stirred at a speed of 220 r / min for 24 h. A pale yellow solution was obtained after stirring. The pale yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide / maleic anhydride.
[0057] Comparative Example 1: Preparation of Cadmium Sulfide / Maleic Anhydride Composite Material by Solvothermal Method
[0058] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. Separately, 0.2 g of maleic anhydride monomer and 0.6 g of PVP dispersant were uniformly dispersed in 25 mL of anhydrous ethanol. After complete dispersion, the two solutions were combined and mixed evenly. The mixture was then placed in a high-pressure reactor and polymerized at 150 °C for 24 h to obtain an orange-yellow solution. The orange-yellow particles were collected by centrifugation and washed three times each with anhydrous ethanol and deionized water. Finally, the particles were dried at 60 °C for 24 h to obtain the orange-yellow product.
[0059] Comparative Example 2: Preparation of Cadmium Sulfide by Photopolymerization
[0060] 2.48 g of sodium thiosulfate (sulfur source) and 11.54 g of cadmium sulfate (cadmium source) were uniformly dispersed in 100 mL of water at a molar ratio of 4.5:1. The solution was then placed in a 125 mm crystallizing dish, and two low-power ultraviolet lamps (254 nm, 8 W) were placed parallel to each other 4.6 cm directly above the solution. The solution was stirred at a speed of 220 r / min for 24 h to obtain a pale yellow solution. The pale yellow particles were then collected by centrifugation, washed three times with deionized water, and finally dried at 60 °C for 24 h to obtain the pale yellow product cadmium sulfide.
[0061] Experiment Example 1: Characterization and Performance Testing
[0062] (1) Morphological observation
[0063] The morphology of the photopolymerized single cadmium sulfide in Comparative Example 2 and the photopolymerized cadmium sulfide / maleic anhydride photocatalyst in Example 1 was observed. Figure 1 Morphology of photo-induced in-situ polymerization of single CdS. Figure 2The image shows the morphology of maleic anhydride produced by photo-initiated in-situ polymerization of cadmium sulfide. Numerous small microspheres were observed growing on the surface of cadmium sulfide. Furthermore, in Examples 2-12, the photopolymerized cadmium sulfide / maleic anhydride photocatalyst also showed the growth of numerous small microspheres on the surface of cadmium sulfide.
[0064] (2) Effects of different synthesis methods on the degradation dye Rhodamine B
[0065] 30 mg of the cadmium sulfide / maleic anhydride photocatalyst material obtained in Comparative Example 1 and Example 2 were weighed and placed in 50 mL of a 18 mg / L Rhodamine B solution. The solution was sonicated for 2 minutes to ensure uniform dispersion of the photocatalyst material. The sonicated solution was then placed under a blue lamp (simulating visible light) for 1 hour to degrade the dye Rhodamine B. The changes in the photodegradation of Rhodamine B by the cadmium sulfide / maleic anhydride material were recorded at 10-minute intervals. The performance curves obtained in Comparative Example 1 and Example 2 are shown below. Figure 3 As shown, a comparison of the two synthesis methods reveals that the catalytic material obtained by photopolymerization exhibits superior degradation performance under visible light.
[0066] (3) Degradation effect of cadmium sulfide in-situ polymerized maleic anhydride photocatalyst (with or without dispersant) on the dye Rhodamine B.
[0067] 30 mg of the cadmium sulfide / maleic anhydride photocatalyst materials obtained in Examples 1 and 2 were weighed and placed in 50 mL of a 18 mg / L Rhodamine B solution. The solution was sonicated for 2 minutes to ensure uniform dispersion. The sonicated solution was then placed under a blue lamp (simulating visible light) for 1 hour to degrade the dye Rhodamine B. The changes in the photodegradation of Rhodamine B by the cadmium sulfide / maleic anhydride material were recorded at 10-minute intervals. The performance curves obtained in Examples 1 and 2 are shown below. Figure 4 As shown, the cadmium sulfide in-situ polymerized maleic anhydride material of the present invention exhibits more stable degradation performance in the presence of a dispersant.
[0068] (4) Degradation effect of cadmium sulfide in-situ polymerized maleic anhydride photocatalyst (different monomer amounts) on the dye Rhodamine B.
[0069] 30 mg of the cadmium sulfide / maleic anhydride photocatalyst material obtained in Examples 2-6 were weighed and placed in 50 mL of a 18 mg / L Rhodamine B solution. The solution was sonicated for 2 minutes to ensure uniform dispersion. The sonicated solution was then placed under a blue lamp (simulating visible light) for 1 hour to degrade the dye Rhodamine B. The changes in the photodegradation of Rhodamine B by the cadmium sulfide / maleic anhydride material were recorded at 10-minute intervals. The performance curves obtained in Examples 2-6 are shown below. Figure 5As shown, it can be seen that, in terms of monomer composite amount, the cadmium sulfide / maleic anhydride photocatalytic material obtained by adding 0.2g maleic anhydride has the best degradation performance under visible light, and can degrade 92% in 30min and 99% in 1h, while single CdS can only degrade 64% in 1h under the same conditions.
[0070] (5) Degradation effect of cadmium sulfide in-situ polymerized maleic anhydride photocatalyst (with different water-to-alcohol ratios) on the dye Rhodamine B
[0071] 30 mg of the cadmium sulfide / maleic anhydride photocatalyst material obtained in Examples 7-12 were weighed and placed in 50 mL of a 18 mg / L Rhodamine B solution. The solution was sonicated for 2 minutes to ensure uniform dispersion. The sonicated solution was then placed under a blue lamp (simulating visible light) for 1 hour to degrade the dye Rhodamine B. The changes in the photodegradation of Rhodamine B by the cadmium sulfide / maleic anhydride material were recorded at 10-minute intervals. The performance curves obtained in Examples 7-12 are shown below. Figure 6 As shown, it can be seen that when the water-to-alcohol ratio is 4:1, the cadmium sulfide / maleic anhydride photocatalyst exhibits the best degradation performance under visible light.
[0072] (6) Repeatability test of cadmium sulfide / maleic anhydride photocatalytic material for degrading dye Rhodamine B
[0073] The cadmium sulfide / maleic anhydride photocatalyst material obtained in Example 2 was continuously subjected to blue light degradation performance tests, and the repeated degradation performance curves are shown below. Figure 7 As shown, the catalytic material exhibits good repeatability in the catalytic degradation of Rhodamine B under visible light.
[0074] (7) Stability test of cadmium sulfide / maleic anhydride photocatalytic material for degrading dye Rhodamine B
[0075] The cadmium sulfide / maleic anhydride photocatalyst material obtained in Example 4 was placed in a natural environment at room temperature for three months. After three months, its blue light degradation performance was tested again, and the degradation performance curves obtained are shown below. Figure 8 As shown in the figure, the catalytic material has good stability.
[0076] In summary, this invention utilizes sulfur source, cadmium source, and monomeric maleic anhydride as raw materials to in-situ polymerize maleic anhydride on cadmium sulfide under ultraviolet light initiation, yielding a cadmium sulfide in-situ polymerized maleic anhydride photocatalytic material. This material exhibits strong degradation of Rhodamine B under visible light, and also demonstrates excellent stability and reproducibility. Furthermore, the preparation method of this invention is simple, safe, requires no external initiator, operates under mild and environmentally friendly conditions, and is easily mass-produced. It overcomes the limitations of current single-CdS photocatalytic performance and has extremely broad application prospects in the degradation of polluting dyes.
[0077] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and these variations still fall within the protection scope of the present invention.
Claims
1. A method for preparing a cadmium sulfide / maleic anhydride photocatalytic material, characterized in that, Includes the following steps: S1. Dissolve sodium thiosulfate and cadmium sulfate in water at a molar ratio of 4-5:
1. Separately, dissolve maleic anhydride monomer in an organic solvent and add a dispersant. The ratio of the dispersant to maleic anhydride is 6:1-5. Then combine the two solutions. S2. Under stirring, the mixed solution from step S1 is placed under a 254nm, 8W ultraviolet lamp for at least 24 hours to obtain cadmium sulfide / maleic anhydride photocatalyst material after photopolymerization reaction.
2. The method for preparing a cadmium sulfide / maleic anhydride photocatalytic material according to claim 1, characterized in that, In step S1, the volume ratio of water to organic solvent is 100:6.25-200.
3. The method for preparing a cadmium sulfide / maleic anhydride photocatalytic material according to claim 1, characterized in that, In step S1, the concentration of maleic anhydride in the organic solvent is 0.2g / 6.25-200mL.
4. The cadmium sulfide / maleic anhydride photocatalytic material prepared by the preparation method according to any one of claims 1-3.
5. The application of the cadmium sulfide / maleic anhydride photocatalytic material according to claim 4 in the photocatalytic degradation of organic dyes.
6. The application according to claim 5, characterized in that, The organic dyes include Rhodamine B.
7. A method for photocatalytic degradation of organic dyes, characterized in that, The cadmium sulfide / maleic anhydride photocatalyst material according to claim 4 is added to a solution containing organic dye, ultrasonically dispersed, and then placed under blue light for degradation for no less than 1 hour.