Preparation of silica-coated silver molybdate nanophotocatalytic material, product and application

Abstract

The application discloses a kind of preparation and product and application of silica-coated silver molybdate nano photocatalytic material, the method includes: silver source and organic silicon source are dissolved in 70 mL anhydrous ethanol according to 100 mmol:1~3 mmol and are ultrasonically dispersed 20~30 min, then stirring 1~2 h;10 mL deionized water is added dropwise in the above suspension, and sol is formed;50 mmol of ammonium molybdate is added in the above sol, and after continuous stirring 1~2 h, it is added in 100 mL reactor, and 160~180 ℃ is reacted 12~18 h, and SiO2-coated silver molybdate precursor is obtained, is washed with deionized water 3~5 times, and is dried in vacuum oven at 60~80 ℃;SiO2-coated silver molybdate precursor is calcined at 400~550 ℃ for 3~5 h.The obtained silica-coated silver molybdate is first adsorbed to methyl orange in darkness and reaches equilibrium, then under ultraviolet light catalytic condition, after 60 min, the degradation of methyl orange reaches 99.8%.

Description

TECHNICAL FIELD

[0001] The present application relates to nanometer photocatalytic material and its preparation and application, specifically to a preparation method of a silica-coated silver molybdate nanometer photocatalytic material, a product and application thereof. BACKGROUND

[0002] Discharge of printing and dyeing wastewater is one of the important reasons for water pollution. A large amount of commercial dyes are discharged every year, which are stable in chemical properties and cause great harm to the ecological environment. The semiconductor material can be activated under sunlight, which can effectively oxidize and degrade organic matter into small molecules such as carbon dioxide and water.

[0003] Silver molybdate is an important semiconductor photocatalyst in the molybdate family, which has good photocatalytic activity. However, the spectral response range of silver molybdate material is narrow, and the photogenerated carrier separation efficiency is low, so the photocatalytic efficiency in the visible light region is low. Therefore, in view of this problem, researchers prepare coated materials based on silver molybdate to improve the photocatalytic activity, thereby greatly improving the photocatalytic performance in the visible light region.

[0004] The present application provides a preparation method of a silica-coated silver molybdate nanometer photocatalytic material. The silica-coated silver molybdate nanometer photocatalytic material is prepared by a sol-assisted solvothermal method. The preparation process is relatively simple and easy to operate. SUMMARY

[0005] In order to overcome the insufficient photocatalytic performance of the existing silver molybdate, the present application aims to provide a preparation method of a silica-coated silver molybdate nanometer photocatalytic material.

[0006] Another purpose of the present application is to provide a silica-coated silver molybdate nanometer photocatalytic material product obtained by the above method.

[0007] Another purpose of the present application is to provide an application of the above product.

[0008] The purpose of the present application is achieved by the following scheme: a preparation method of a silica-coated silver molybdate nanometer photocatalytic material, which prepares a silica-coated silver molybdate nanometer photocatalytic material by a solvothermal method, including the following steps:

[0009] (1) Dissolve 100 mmol of silver source and 1-3 mmol of organic silicon source in 70 mL of anhydrous ethanol, and ultrasonically disperse for 20-30 min, and then stir for 1-2 h;

[0010] (2) Add 10 mL of deionized water dropwise to the above suspension to form a sol;

[0011] (3) 50 mmol of ammonium molybdate is added to the sol, and after continuous stirring for 1-2 h, 100 mL of the reaction kettle is added, and the reaction is carried out at 160-180 ℃ for 12-18 h to obtain a SiO2-coated silver molybdate precursor, which is washed with deionized water for 3-5 times and dried in a vacuum oven at 60-80 ℃;

[0012] (4) The SiO2-coated silver molybdate precursor is calcined at 400-550 ℃ for 3-5 h to obtain a SiO2-coated silver molybdate.

[0013] Preferably, in the step (1), the silver source is one or a combination of silver acetate, silver nitrate or silver chlorate.

[0014] Preferably, in the step (1), the silicon source is one or a combination of tetraethyl orthosilicate or tetrabutyl orthosilicate.

[0015] The application provides a SiO2-coated silver molybdate nano-photocatalytic material prepared according to any of the above methods.

[0016] The application provides an application of the SiO2-coated silver molybdate nano-photocatalytic material in degrading methyl orange in dye wastewater.

[0017] Beneficial effects:

[0018] The application provides a preparation method of a SiO2-coated silver molybdate nano-photocatalytic material, and the SiO2-coated silver molybdate nano-photocatalytic material is prepared by a sol-assisted solvothermal method. The preparation process is relatively simple and easy to operate. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 It is a UV photocatalytic degradation diagram of the SiO2-coated silver molybdate nano-photocatalytic material of Example 1. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0021] Example 1

[0022] A SiO2-coated silver molybdate nano-photocatalytic material is prepared by a solvothermal method, and is prepared according to the following steps:

[0023] (1) AgNO3 and tetraethyl orthosilicate were dissolved in 70 mL of anhydrous ethanol at 100 mmol: 1 mmol, ultrasonic dispersion for 20 min, and stirring for 1 h to obtain a suspension;

[0024] (2) 10 mL of deionized water was added dropwise to the above suspension to form a sol;

[0025] (3) 50 mmol of ammonium molybdate was added to the above sol, continuously stirred for 1 h, and then added to a 100 mL reaction kettle, reacted at 160 ℃ for 18 h, and then washed with deionized water for 5 times, and dried in a vacuum oven at 60 ℃;

[0026] (4) The SiO2-coated silver molybdate precursor was calcined at 400 ℃ for 5 h to obtain the SiO2-coated silver molybdate.

[0027] Figure 1 is a UV light catalytic degradation diagram of the SiO2-coated silver molybdate photocatalytic material.

[0028] The SiO2-coated silver molybdate photocatalytic material first reached equilibrium in the adsorption of methyl orange in the dark, and then under the condition of UV light catalysis, the degradation of methyl orange reached 99.8% after 60 min.

[0029] Example 2

[0030] A SiO2-coated silver molybdate nano-photocatalytic material was prepared according to the following steps, which was similar to the steps of Example 1:

[0031] (1) Ag acetate and tetraethyl orthosilicate were dissolved in 70 mL of anhydrous ethanol at 100 mmol: 2 mmol, ultrasonic dispersion for 30 min, and stirring for 2 h to obtain a suspension;

[0032] (2) 10 mL of deionized water was added dropwise to the above suspension to form a sol;

[0033] (3) 50 mmol of ammonium molybdate was added to the above sol, continuously stirred for 2 h, and then added to a 100 mL reaction kettle, reacted at 180 ℃ for 12 h, and then washed with deionized water for 5 times, and dried in a vacuum oven at 80 ℃;

[0034] (4) The SiO2-coated silver molybdate precursor was calcined at 450 ℃ for 4 h to obtain the SiO2-coated silver molybdate.

[0035] Example 3

[0036] A SiO2-coated silver molybdate nano-photocatalytic material was prepared according to the following steps, which was similar to the steps of Example 1:

[0037] (1) ultrasonic dispersion of 100 mmol of silver chlorate and 3 mmol of tetrabutyl orthosilicate in 70 mL of anhydrous ethanol for 30 min, followed by stirring for 2 h to obtain a suspension;

[0038] (2) dropwise addition of 10 mL of deionized water to the suspension to form a sol;

[0039] (3) addition of 50 mmol of ammonium molybdate to the sol, continuous stirring for 2 h, and then addition to a 100 mL reaction kettle, reaction at 180 ℃ for 12 h to obtain a SiO2-coated silver molybdate precursor, which was washed with deionized water for 5 times and dried in a vacuum oven at 80 ℃;

[0040] (4) calcination of the SiO2-coated silver molybdate precursor at 500 ℃ for 3 h to obtain a silica-coated silver molybdate.

Claims

1. A method for preparing silica-coated silver molybdate nanophotocatalyst material, characterized in that, The preparation of silica-coated silver molybdate nano-photocatalysts via a solvothermal method includes the following steps: (1) Dissolve the silver source and the organosilicon source in 70 mL of anhydrous ethanol at a ratio of 100 mmol: 1~3 mmol, disperse them by ultrasonication for 20~30 min, and then stir for 1~2 h to obtain a suspension; (2) Add 10 mL of deionized water dropwise to the above suspension to form a sol; (3) Add 50 mmol of ammonium molybdate to the above sol, stir continuously for 1-2 h, then add to 100 mL of reaction vessel, react at 160-180℃ for 12-18 h to obtain SiO2-coated silver molybdate precursor, wash with deionized water 3-5 times, and dry in a vacuum oven at 60-80℃. (4) The SiO2-coated silver molybdate precursor was calcined at 400~550℃ for 3~5 h to obtain silica-coated silver molybdate; The silver source is one or a combination of silver acetate, silver nitrate, or silver chlorate.

2. The method for preparing silica-coated silver molybdate nanophotocatalyst material according to claim 1, characterized in that, The organosilicon source is one or a combination of tetraethyl orthosilicate or tetrabutyl orthosilicate.

3. The method for preparing a silica-coated silver molybdate nanophotocatalyst material according to any one of claims 1 to 2, characterized in that, Prepare according to the following steps: (1) Silver nitrate and tetraethyl orthosilicate were dissolved in 70 mL of anhydrous ethanol at a ratio of 100 mmol: 1 mmol and ultrasonically dispersed for 20 min, then stirred for 1 h to obtain a suspension; (2) Add 10 mL of deionized water dropwise to the above suspension to form a sol; (3) Add 50 mmol of ammonium molybdate to the above sol, stir continuously for 1 h, then add to 100 mL of reaction vessel, react at 160℃ for 18 h to obtain SiO2 coated silver molybdate precursor, wash with deionized water 5 times, and dry in a vacuum oven at 60℃. (4) The SiO2-coated silver molybdate precursor was calcined at 400℃ for 5 h to obtain silica-coated silver molybdate.

4. The method for preparing a silica-coated silver molybdate nanophotocatalyst material according to any one of claims 1 to 2, characterized in that, Prepare according to the following steps: (1) Silver acetate and tetraethyl orthosilicate were dissolved in 70 mL of anhydrous ethanol at a ratio of 100 mmol: 2 mmol and ultrasonically dispersed for 30 min, then stirred for 2 h to obtain a suspension. (2) Add 10 mL of deionized water dropwise to the above suspension to form a sol; (3) Add 50 mmol of ammonium molybdate to the above sol, stir continuously for 2 h, then add to 100 mL of reaction vessel, react at 180 °C for 12 h to obtain SiO2-coated silver molybdate precursor, wash with deionized water 5 times, and dry in a vacuum oven at 80 °C. (4) The SiO2-coated silver molybdate precursor was calcined at 450 °C for 4 h to obtain silica-coated silver molybdate.

5. The method for preparing a silica-coated silver molybdate nanophotocatalyst material according to any one of claims 1 to 2, characterized in that, Prepare according to the following steps: (1) Silver chlorate and tetrabutyl silicate were dissolved in 70 mL of anhydrous ethanol at a ratio of 100 mmol: 3 mmol and ultrasonically dispersed for 30 min, then stirred for 2 h to obtain a suspension; (2) Add 10 mL of deionized water dropwise to the above suspension to form a sol; (3) Add 50 mmol of ammonium molybdate to the above sol, stir continuously for 2 h, then add to 100 mL of reaction vessel, react at 180℃ for 12 h to obtain SiO2 coated silver molybdate precursor, wash with deionized water 5 times, and dry in a vacuum oven at 80℃. (4) The SiO2-coated silver molybdate precursor was calcined at 500°C for 3 h to obtain silica-coated silver molybdate.

6. A silica-coated silver molybdate nanophotocatalyst material, characterized in that... Prepared according to any one of claims 1-5.

7. An application of the silica-coated silver molybdate nanophotocatalyst material according to claim 6 in the degradation of methyl orange in dye wastewater treatment.

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