CN-115999588-B - Preparation method and application of nanoparticle heterojunction visible light catalyst

Abstract

The invention discloses a preparation method of a nano particle heterojunction photocatalyst Bi 4 V 2 O 11 /Ag/AgCl, which comprises the steps of dissolving Bi (NO 3 ) 3 ·5H 2 O、NH 4 VO 3 and urea in glycol aqueous solution, regulating the pH value of the obtained mixed solution to 8.0-10.0 by using dilute ammonia water, transferring the mixed solution into a reaction kettle for hydrothermal synthesis, naturally cooling, alternately washing by using deionized water and ethanol, drying to obtain Bi 4 V 2 O 11 powder, sequentially adding Bi 4 V 2 O 11 powder, naCl and AgNO 3 into ultrapure water, stirring to obtain the mixed solution, irradiating the mixed solution with a 300W xenon lamp for 45-60min, centrifuging to obtain a precipitate, washing and drying to obtain the nano particle heterojunction photocatalyst which can reduce the photo-generated electron hole recombination rate.

Inventors

• LU JINFENG
• HU JIAQI
• NI LINJIE
• MAO JIE
• YANG YUE
• LI SHANSHAN
• WANG YIFEI

Assignees

• 南开大学

Dates

Publication Date

20260512

Application Date

20221110

Claims (4)

1. 1. The preparation method of the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst is characterized by comprising the following steps of: (1) Dissolving Bi (NO 3 ) 3 ·5H 2 O、NH 4 VO 3 and urea in glycol water solution to obtain a mixed solution 1, regulating the pH value of the obtained mixed solution 1 to 8.0-10.0 by using dilute ammonia water, transferring the mixed solution 1 into a reaction kettle for hydrothermal synthesis, naturally cooling, alternately washing with deionized water and ethanol, and drying to obtain Bi 4 V 2 O 11 powder; (2) Sequentially adding the obtained Bi 4 V 2 O 11 powder, naCl and AgNO 3 into ultrapure water, stirring to obtain a mixed solution 2, irradiating the mixed solution 2 with a 300W xenon lamp, centrifuging to obtain a precipitate, alternately washing with deionized water and ethanol, drying, and naturally cooling to obtain the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst, wherein the particle size of the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst is 3-10 nm, ag/AgCl accounts for 15-35% of the total weight of the catalyst, and the balance Bi 4 V 2 O 11 .
2. 2. The method for preparing the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst according to claim 1, wherein in the step (1), the concentration of the dilute ammonia water is 1-3 mol/L, and the pH is adjusted to 8.0-10.0.
3. 3. The method for preparing a Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst according to claim 1, wherein in the step (2), the 300W xenon lamp irradiation time is 45-60 min.
4. 4. The use of the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst prepared by the preparation method of the Bi 4 V 2 O 11 /Ag/AgCl nanoparticle heterojunction photocatalyst according to any one of claims 1 to 3 for degrading organic pollutants, wherein the organic pollutants are tetracycline or ciprofloxacin.

Description

Preparation method and application of nanoparticle heterojunction visible light catalyst Technical Field The invention belongs to the technical field of environmental remediation and pollution control, and particularly relates to a preparation method and application of a Bi 4V2O11/Ag/AgCl nanoparticle heterojunction photocatalyst, wherein the photocatalyst is used for removing antibiotics remained in water under visible light. Background In recent years, antibiotics, personal care products and other pharmaceutical toxic organic chemicals are frequently detected in water environments. However, many studies have reported that antibiotics, particularly tetracyclines, are frequently detected in sewage treatment plants, and it is difficult to effectively remove these emerging contaminants by conventional sewage treatment processes due to long-term stability and low biodegradability, so that it is necessary to find a suitable water restoration technology and thus an effective way to deeply treat residual antibiotics in water environments. On one hand, the photocatalysis technology has the advantages of mild reaction conditions, low energy consumption, less secondary pollution and the like, plays an important role in the treatment of water environment pollutants, but the problems of too high photo-generated electron-hole recombination rate, insufficient oxidation capacity and the like severely restrict the development prospect, and on the other hand, the metal nano particles as cocatalysts can trigger a metal plasma induction effect, so that the charge separation efficiency is improved, the light absorption capacity of the material is improved, and the degradation-resistant organic pollutants can be effectively removed by introducing the photocatalyst into the photocatalysis field, but the problems of unstable metal nano particles, metal ion dissolution and the like exist. Therefore, if the photocatalysis technology and the metal nano particles can be coupled, the visible light absorption range can be increased, the rate of photo-generated electron-hole recombination can be reduced, and the degradation performance of pollutants is greatly improved. As a typical Bi-based photocatalyst, bi 4V2O11 has a good photocatalytic performance, however, since the light absorption capacity is limited, the recombination speed of photo-generated charges is high, which limits the wide application of Bi 4V2O11, and if Bi 4V2O11 forms a heterojunction with a semiconductor having a suitable energy band structure, the photo-generated electron and hole recombination efficiency can be greatly reduced, thereby improving the catalytic performance of Bi 4V2O11. The invention application with the application number 202011474708.2 discloses a Bi 4V2O11/BiVO4 heterojunction photocatalyst which is simple in process, high in efficiency and beneficial to industrial production, and the heterojunction photocatalyst is applied to degradation of rhodamine B as an organic pollutant. According to the invention, the Bi 4V2O11/BiVO4 heterojunction photocatalyst is obtained by a hydrothermal method, and rhodamine B is degraded by using visible light as a light source. However, the catalyst is not easy to control the formation of the catalyst particle size in the synthesis process, and aggregation of particles can easily occur, so that photo-generated electron-hole pairs are easy to recombine, and the number of active sites of the catalyst is reduced and the catalytic efficiency is reduced. The invention application number 201710290817.0 discloses a method for preparing a CdS/Bi 4V2O11 heterojunction photocatalyst with low energy consumption, the invention adopts a two-step solvothermal method to prepare the CdS/Bi 4V2O11 heterojunction photocatalyst, and the catalytic activity of the prepared photocatalyst is inspected by adjusting two parts of different molar ratios, so that rhodamine B can be degraded in a photocatalytic manner. But the surface charge transfer efficiency of the material is not high. The invention application with the application number 202010721850.6 discloses a Bi 4V2O11/g-C3N4 heterojunction photocatalyst, a preparation method and application thereof, and the Bi 4V2O11/g-C3N4 heterojunction photocatalyst prepared by an in-situ hydrothermal method can be used for catalytic reduction of CO 2. However, the preparation method of the material is complex, and the required catalytic reduction time is long. In addition, different environments have larger influence on the activity of the catalyst, the catalyst is more easily agglomerated in water environment, and the application difficulty is higher. Therefore, the research and development of the metal nanoparticle heterojunction photocatalyst which is simple in preparation method, can be applied to water environment, can control and prepare proper particle size, can improve the transfer efficiency of photo-generated electrons and inhibit the recombination of electron hole pairs, and can rap