Preparation method of Ag3PO4 / UiO-66 composite photocatalyst

Abstract

The invention discloses a preparation method of Ag3PO4 composite photocatalytic particles, belongs to the field of preparation of photocatalytic materials, and aims to solve the problem of low photocatalytic efficiency. The preparation method comprises the following steps: 1, preparation of Uio-66: oxidizing and dissolving chlorine in N, N-dimethylformamide, carrying out ultrasonic dispersion to fully dissolve the chlorine, weighing terephthalic acid, a hydrochloric acid solution and N, N-dimethylformamide, respectively adding the weighed terephthalic acid, hydrochloric acid and N, N-dimethylformamide into the dispersed mixed solution, transferring the mixed solution into a reaction kettle, and heating the mixed solution in a drying oven at 80 DEG C for 24 hours; and cooling to room temperature, and collecting a solid product to obtain Uio-66. 2, preparation of an Ag3PO4 / UiO-66 compound: weighing UiO-66 powder, preparing a solution, and carrying out ultrasonic dispersion; adding a proper amount of silver nitrate solid, carrying out ultrasonic treatment, adding a disodium hydrogen phosphate dodecahydrate aqueous solution into the mixed solution, and carrying out suction filtration separation; and finally, drying in a 60 DEG C constant-temperature drying box to obtain the compounds with different proportions.

Description

Technical Field

[0001] The present invention belongs to the field of preparation of photocatalytic degradation materials, and relates to a preparation method of an Ag3PO4 / UiO-66 composite photocatalyst. Background Art

[0002] As a new type of water treatment technology, photocatalytic technology has gradually become a research hotspot. Under the excitation of natural light, nanoscale catalysts can degrade organic pollutants in wastewater (such as dyes, pesticides, organic fuels, etc.) to generate odorless and harmless substances such as carbon dioxide and water. Antibiotics are representatives of such pollutants. Antibiotics are a type of drug with a high usage frequency in people's daily lives. Due to the massive use and abuse of antibiotic drugs, they are continuously transported into environmental media and are frequently detected in river water samples in various basins. At the same time, the massive use of antibiotics has also led to an increasing number of drug-resistant bacteria and resistance genes in the environment, posing a potential threat to human health and the ecological environment. Therefore, the treatment research on antibiotic-polluted water bodies has received increasing attention. In recent years, research has shown that photocatalytic technology is expected to effectively degrade antibiotic organic pollutants. However, traditional inorganic semiconductor materials are limited by their own limitations (such as low specific surface area, difficulty in modification, etc.), which restricts the further improvement of their photocatalytic activity. The emerging MOFs materials have advantages such as a large specific surface area, high porosity, and highly adjustable structure that are incomparable to traditional materials, and are expected to become an ideal photocatalytic material for treating antibiotic-containing wastewater.

[0003] MOF is an ideal carrier material due to its rich pore structure and adjustable composition. Among them, UiO-66 is a rigid metal-organic framework material with Zr as the metal center and terephthalic acid (H2BDC) as the organic ligand, and has good hydrothermal stability and chemical stability. Summary of the Invention

[0004] The purpose of the present invention is to solve the problem of the low photocatalytic efficiency of UIO-66, and to provide a preparation method of an Ag3PO4 / UiO-66 composite photocatalyst.

[0005] The preparation method of the Ag3PO4 / UiO-66 composite photocatalyst of the present invention is realized according to the following steps:

[0006] I. Preparation of UiO-66: Weigh 0.7417 g of zirconium oxychloride and dissolve it in 40 mL of N,N-dimethylformamide. Sonicate it to disperse and fully dissolve. Weigh 0.4596 g of terephthalic acid, 4 mL of hydrochloric acid solution, and 20 mL of N,N-dimethylformamide, and add them to the above-mentioned well-dispersed mixture respectively. Transfer the mixture to three 20-mL reaction vessels, and the volume of the solution in each reaction vessel should not exceed half of the container volume. Heat it in an oven at 80 °C for 24 hours. After the reaction is completed, cool the temperature of the reaction vessel to room temperature, and collect the white solid product by centrifugation. First, wash it three times with N,N-dimethylformamide, and then wash it three times with ethanol. Place the product on a drying oven to dry completely to obtain UiO-66.;

[0007] II. Hydrothermal preparation of composite particles: Weigh 100 mg of UiO-66 powder, mix it with 5 mL of deionized water, and sonicate for 30 min to obtain a MOF dispersion. Add an appropriate amount of 100 mg of silver nitrate (AgNO3) solid to the MOF dispersion, continue to sonicate for 30 min to obtain a mixture of the MOF dispersion and the AgNO3 solution, and place it on a magnetic stirrer to start stirring. Weigh 70 mg of disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O) powder, dissolve it in 5 mL of deionized water, and gradually add it dropwise to the stirred mixture. Stop stirring after 4 h. Separate the solid powder from the reaction system by suction filtration and wash it three times with deionized water. Finally, dry it in a constant-temperature drying oven at 60 °C and then grind it to obtain the product.

[0008] The present invention proposes a simple preparation method for composite particles, which effectively improves the photocatalytic effect.

[0009] The preparation method of the Ag3PO4 / UiO-66 composite photocatalyst described in the present invention has the following beneficial effects:

[0010] 1. The preparation method is simple and easy to operate.

[0011] 2. The Ag3PO4 / UiO-66 composite photocatalyst is compounded, effectively improving the photocatalytic oxidation performance. Description of the Drawings

[0012] Figure 1 is the XRD pattern of UiO-66 obtained in the example;

[0013] Figure 2 The XRD pattern of the Ag3PO4 / UiO-66 composite photocatalyst obtained in the example;

[0014] Figure 3 is the absorption curve of UiO-66 obtained in the example during the degradation of methylene blue.

[0015] Figure 4It is the absorption curve when the Ag3PO4 / UiO-66 composite photocatalyst obtained in the embodiment degrades methylene blue. Detailed implementation manners Detailed implementation manner one:

[0017] The preparation method of the Ag3PO4 / UiO-66 composite photocatalyst in this implementation manner is carried out according to the following steps:

[0018] I. Preparation of UiO-66: Weigh 0.7417 g of zirconium oxychloride and dissolve it in 40 mL of N,N-dimethylformamide. Ultrasonically disperse it to make it fully dissolve. Weigh 0.4596 g of terephthalic acid, 4 mL of hydrochloric acid solution, and 20 mL of N,N-dimethylformamide, and add them to the above-mentioned well-dispersed mixture respectively. Transfer it to 3 20-mL reaction kettles, and the volume of the solution in each reaction kettle does not exceed half of the container volume. Heat it in an oven at 80 °C for 24 hours. When the reaction is over, cool the temperature of the reaction kettle to room temperature, and centrifuge to collect the white solid product. First, wash it 3 times with N,N-dimethylformamide, and then wash it 3 times with ethanol. Place the product on a drying oven to dry completely to obtain UiO-66.

[0019] II. Hydrothermal preparation of composite particles: Weigh 100 mg of UiO-66 powder, mix it with 5 mL of deionized water, and ultrasonically disperse it for 30 min to obtain a MOF dispersion. Add an appropriate amount of 100 mg of silver nitrate (AgNO3) solid to the MOF dispersion, continue to ultrasonically disperse it for 30 min to obtain a mixture of the MOF dispersion and the AgNO3 solution, and place it on a magnetic stirrer to start stirring. Weigh 70 mg of disodium hydrogen phosphate dodecahydrate ((Na2HPO4·12H2O)) powder, dissolve it in 5 mL of deionized water, and dropwise add it to the stirred mixture. Stop stirring after 4 h. Separate the solid powder from the reaction system by suction filtration and wash it 3 times with deionized water. Finally, dry it in a constant temperature drying oven at 60 °C and then grind it to obtain. Detailed implementation manner two:

[0021] The difference between this implementation manner and the first detailed implementation manner is that the amount of silver nitrate in step II is 150 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 105 mg. Detailed implementation manner three:

[0023] The difference between this implementation manner and the first or second detailed implementation manner is that the amount of silver nitrate in step II is 200 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 140 mg Detailed implementation manner four:

[0025] The difference between this implementation manner and any one of the first to third detailed implementation manners is that the amount of silver nitrate in step II is 250 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 170 mg.. Specific Embodiment 5:

[0027] The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that the amount of silver nitrate in Step 2 is 300 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 210 mg.

[0028] Example:

[0029] The preparation method of the Ag3PO4 / UiO-66 composite photocatalyst in this example is implemented according to the following steps:

[0030] I. Preparation of UiO-66: Weigh 0.7417 g of zirconium oxychloride and dissolve it in 40 mL of N,N-dimethylformamide. Ultrasonically disperse it to make it fully dissolve. Weigh 0.4596 g of terephthalic acid, 4 mL of hydrochloric acid solution, and 20 mL of N,N-dimethylformamide, and add them to the above-mentioned well-dispersed mixed solution respectively. Transfer it to 3 20-mL reaction kettles, and the volume of the solution in each reaction kettle does not exceed half of the container volume. Heat it in an oven at 80 °C for 24 hours. When the reaction is over, cool the temperature of the reaction kettle to room temperature, and centrifuge to collect the white solid product. First, wash it 3 times with N,N-dimethylformamide, and then wash it 3 times with ethanol. Place the product on a drying oven to dry completely to obtain UiO-66.

[0031] II. Preparation of Ag3PO4 / UiO-66 composite: Weigh 100 mg of UiO-66 powder, mix it with 5 mL of deionized water, and ultrasonically disperse it for 30 min to prepare a MOF dispersion. Add an appropriate amount (100 mg, 150 mg, 200, 250 mg, 300 mg) of silver nitrate (AgNO3) solid to the MOF dispersion, continue to ultrasonically disperse it for 30 min to obtain a mixed solution of MOF dispersion and AgNO3 solution, and place it on a magnetic stirrer to start stirring. Weigh an appropriate amount (70 mg, 105 mg, 140 mg, 175 mg, 210 mg) of disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O) powder, dissolve it in 5 mL of deionized water, and dropwise add it to the stirred mixed solution. Stop stirring after 4 h. Fourth step: Separate the solid powder from the reaction system by suction filtration and wash it 3 times with deionized water. Finally, dry it in a constant temperature drying oven at 60 °C and then grind it to obtain it.

[0032] From Figure 1 (UiO-66) and Figure 2 the XRD patterns of (Ag3PO4 / UiO-66), obvious diffraction peaks appear, which are basically consistent with the literature records.

Claims

1. A preparation method of Ag3PO4 / UiO-66 composite photocatalyst, characterized in that The method is implemented according to the following steps: I. Preparation of precursor UiO-66: Weigh 0.7417 g of zirconium oxychloride and dissolve it in 40 mL of N,N-dimethylformamide. Ultrasonically disperse it to fully dissolve. Weigh 0.4596 g of terephthalic acid, 4 mL of hydrochloric acid solution, and 20 mL of N,N-dimethylformamide, and add them to the above-dispersed mixture respectively. Transfer it to three 20-mL reaction kettles, and the volume of the solution in each reaction kettle does not exceed half of the container volume; heat it in an oven at 80 °C for 24 hours; when the reaction is over, cool the temperature of the reaction kettle to room temperature, and centrifuge to collect the white solid product; first wash it 3 times with N,N-dimethylformamide, and then wash it 3 times with ethanol, and place the product on a drying oven to dry completely to obtain UiO-66; II. Preparation of Ag3PO4 / UiO-66: Weigh 100 mg of UiO-66 powder, mix it with 5 mL of deionized water, and ultrasonically disperse it for 30 min to prepare a MOF dispersion. Add an appropriate amount of 100 mg of silver nitrate (AgNO3) solid to the MOF dispersion, and continue to ultrasonically disperse it for 30 min to obtain a mixed solution of the MOF dispersion and the AgNO3 solution, and place it on a magnetic stirrer to start stirring. Weigh 70 mg of disodium hydrogen phosphate dodecahydrate (Na2HPO4·12H2O) powder, dissolve it in 5 mL of deionized water, and add it dropwise to the stirred mixed solution. Stop stirring after 4 h. Separate the solid powder from the reaction system by suction filtration and wash it 3 times with deionized water. Finally, dry it in a constant-temperature drying oven at 60 °C and then grind it to obtain composites with different ratios.

2. Specific Embodiment 2: The difference between this embodiment and Specific Embodiment 1 is that the amount of silver nitrate in step II is 150 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 105 mg.

3. Specific Embodiment 3: The difference between this embodiment and Specific Embodiment 1 or 2 is that the amount of silver nitrate in step II is 200 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 140 mg.

4. Specific Embodiment 4: The difference between this embodiment and any one of Specific Embodiments 1 to 3 is that the amount of silver nitrate in step II is 250 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 170 mg.

5. Specific Embodiment 5: The difference between this embodiment and any one of Specific Embodiments 1 to 4 is that the amount of silver nitrate in step II is 300 mg, and the amount of disodium hydrogen phosphate dodecahydrate is 210 mg.

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