阅读说明：本技术 一种光催化剂的制备方法 (Preparation method of photocatalyst ) 是由 李秋霞 王九鑫 梁飞燕 于 2019-12-31 设计创作，主要内容包括：本发明公开了一种光催化剂的制备方法,属于光催化剂技术领域。该方法包括：步骤(1)：制备WO<Sub>3</Sub>-Bi<Sub>2</Sub>WO<Sub>6</Sub>；步骤(2)：通过WO<Sub>3</Sub>-Bi<Sub>2</Sub>WO<Sub>6</Sub>制备Ag<Sub>3</Sub>PO<Sub>4</Sub>-WO<Sub>3</Sub>-Bi<Sub>2</Sub>WO<Sub>6</Sub>。本发明中Bi<Sub>2</Sub>WO<Sub>6</Sub>的CB中积累的电子表现出很高的还原能力,可还原O<Sub>2</Sub>以生成·O<Sub>2</Sub><Sup>-</Sup>,WO<Sub>3</Sub>的VB中的空穴显示出高氧化能力,可氧化H<Sub>2</Sub>O生成大量的活性·OH自由基,Ag<Sub>3</Sub>PO<Sub>4</Sub>充当WO<Sub>3</Sub>和Bi<Sub>2</Sub>WO<Sub>6</Sub>之间的电荷传输桥,Ag<Sub>3</Sub>PO<Sub>4</Sub>和WO<Sub>3</Sub>-Bi<Sub>2</Sub>WO<Sub>6</Sub>之间异质结结构的形成有效地促进了Z轴机制下电子-空穴对的分离,增强了光催化性能和稳定性。(The invention discloses a preparation method of a photocatalyst, and belongs to the technical field of photocatalysts. The method comprises the following steps: step (1): preparation of WO 3 ‑Bi 2 WO 6 (ii) a Step (2): by WO 3 ‑Bi 2 WO 6 Preparation of Ag 3 PO 4 ‑WO 3 ‑Bi 2 WO 6 . Bi in the invention 2 WO 6 The accumulated electronic watch in CB (B) shows a high reducing ability and can reduce O 2 To produce O 2 ‑ ，WO 3 Has a high oxidation power, can oxidize H 2 O generates a large amount of active OH radicals, Ag 3 PO 4 Acting as WO 3 And Bi 2 WO 6 Charge transport bridges between, Ag 3 PO 4 And WO 3 ‑Bi 2 WO 6 The formation of the heterojunction structure between the two layers effectively promotes the separation of electron-hole pairs under a Z-axis mechanism, and the photocatalytic performance and stability are enhanced.)

1. A method for preparing a photocatalyst, the method comprising:

step (1): preparation of WO₃-Bi₂WO₆；

Step (2): by said WO₃-Bi₂WO₆Preparation of Ag₃PO₄-WO₃-Bi₂WO₆。

2. The method of claim 1, wherein the step (1) comprises: adding Bi (NO)₃)₃·5H₂O is dissolved in 11mL of 4mol/L HNO₃Stirring the solution for 10 minutes at 40 ℃ to obtain a mixed solution; adding Na dropwise to the mixed solution₂WO₄·2H₂O, after the dropwise addition is finished, stirring the mixture for 24 hours at the temperature of 40 ℃, then transferring the mixture into a 60ml Teflon-lined autoclave, keeping the mixture at the temperature of 160 ℃ for 20 hours, cooling the mixture to room temperature, and collecting precipitates; washing the precipitate with distilled water and ethanol for several times, and drying at 60 deg.C to obtain the WO₃-Bi₂WO₆。

3. The method of claim 2, wherein the WO is₃-Bi₂WO₆WO of Zhong₃And Bi₂WO₆The mass ratio of (A) to (B) is 0.2: 1.

4. The method according to claim 3, wherein the step (2) comprises: subjecting said WO to₃-Bi₂WO₆Dispersing in 60mL distilled water, stirring for 20min, and adding AgNO₃And stirred for 30 minutes to obtain a suspension; mixing Na₃PO₄Dissolving in 30mL of distilled water, and stirring for 30min to obtain a mixed solution; dropwise adding the mixed liquid into the suspension through an acid burette, heating in a water bath at 80 ℃ for 4 hours, and collecting solid; washing the solid with distilled water and ethanol for multiple times, and then drying the solid in a vacuum drying oven at 60 ℃ for 10 hours to obtain the Ag₃PO₄-WO₃-Bi₂WO₆。

5. The method of claim 4, wherein the Ag is selected from the group consisting of Ag, and combinations thereof₃PO₄-WO₃-Bi₂WO₆Middle Ag₃PO₄、WO₃And Bi₂WO₆The mass ratio of the components is 0.1 to0.5: 0.2: 0.1, preferably 0.3: 0.2: 0.1.

Technical Field

The invention relates to the technical field of photocatalysts, in particular to a preparation method of a photocatalyst.

Background

The photocatalyst is a general name of chemical substances capable of playing a role in catalysis under the excitation of photons, and is mainly applied to a plurality of advanced fields such as environmental purification, self-cleaning materials, advanced new energy, cancer medical treatment, high-efficiency antibiosis and the like.

Dye contaminants are inevitably released into aquatic environments due to the mass production of the textile industry, which is harmful to human health. Dyes are important organic contaminants that are released as wastewater in ecosystems and are an important source of aesthetic contamination, eutrophication, and turbulence in aquatic organisms. Most dyes have the ability to resist biodegradation and direct photolysis, and many nitrogen-containing dyes (such as rhodamine b (rhb)) undergo natural reductive anaerobic degradation to produce potentially carcinogenic aromatic amines, whereas biological oxidation and physicochemical treatments are generally ineffective at removing the dye. Therefore, extensive studies were made on RhB degradation. Photocatalytic degradation of RhB is considered to be one of the more promising strategies to address this crisis, e.g. TiO₂，Bi₂WO₆And Ag₃PO₄. However, these semiconductor photocatalysts exhibit unsatisfactory photoactivity.

Disclosure of Invention

In order to solve the problems in the prior art, embodiments of the present invention provide a method for preparing a photocatalyst. The method comprises the following steps: step (1): preparation of WO₃-Bi₂WO₆(ii) a Step (2): by said WO₃-Bi₂WO₆Preparation of Ag₃PO₄-WO₃-Bi₂WO₆。

Further, the step (1) includes: adding Bi (NO)₃)₃·5H₂O is dissolved in 11mL of 4mol/L HNO₃Stirring the solution for 10 minutes at 40 ℃ to obtain a mixed solution; adding Na dropwise to the mixed solution₂WO₄·2H₂O, after the dropwise addition is finished, stirring the mixture for 24 hours at the temperature of 40 ℃, then transferring the mixture into a 60ml Teflon-lined autoclave, keeping the mixture at the temperature of 160 ℃ for 20 hours, cooling the mixture to room temperature, and collecting precipitates; washing the precipitate with distilled water and ethanol for several times, and drying at 60 deg.C to obtain the WO₃-Bi₂WO₆。

Further, the WO₃-Bi₂WO₆WO of Zhong₃And Bi₂WO₆The mass ratio of (A) to (B) is 0.2: 1.

Further, the step (2) includes: subjecting said WO to₃-Bi₂WO₆Dispersing in 60mL distilled water, stirring for 20min, and adding AgNO₃And stirred for 30 minutes to obtain a suspension; mixing Na₃PO₄Dissolving in 30mL of distilled water, and stirring for 30min to obtain a mixed solution; dropwise adding the mixed liquid into the suspension through an acid burette, heating in a water bath at 80 ℃ for 4 hours, and collecting solid; washing the solid with distilled water and ethanol for multiple times, and then drying the solid in a vacuum drying oven at 60 ℃ for 10 hours to obtain the Ag₃PO₄-WO₃-Bi₂WO₆。

Further, the Ag₃PO₄-WO₃-Bi₂WO₆Middle Ag₃PO₄、WO₃And Bi₂WO₆The mass ratio of the components is 0.1-0.5: 0.2: 0.1, preferably 0.3: 0.2: 0.1.

The technical scheme provided by the embodiment of the invention has the following beneficial effects: bi in the invention₂WO₆The accumulated electronic watch in CB (B) shows a high reducing ability and can reduce O₂To produce O₂ ^-，WO₃Has a high oxidation power, can oxidize H₂O generates a large amount of active OH radicals, Ag₃PO₄Acting as WO₃And Bi₂WO₆Between the twoBridge, Ag₃PO₄And WO₃-Bi₂WO₆The formation of the heterojunction structure between the two layers effectively promotes the separation of electron-hole pairs under a Z-axis mechanism, and the photocatalytic performance and stability are enhanced.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a flow chart of a method for preparing a photocatalyst according to an embodiment of the present invention;

FIG. 2 is a flow chart of another method for preparing a photocatalyst provided in example two of the present invention;

FIG. 3 is Bi₂WO₆、WO₃-Bi₂WO₆And different mass fractions of Ag₃PO₄-WO₃-Bi₂WO₆XRD analysis pattern of (a);

FIG. 4 shows Bi₂WO₆、WO₃-Bi₂WO₆And different mass fractions of Ag₃PO₄-WO₃-Bi₂WO₆(ii) ultraviolet-visible diffuse reflectance spectroscopy;

FIG. 5 shows Bi₂WO₆、WO₃-Bi₂WO₆And different mass fractions of Ag₃PO₄-WO₃-Bi₂WO₆A photocurrent transient response diagram under visible light irradiation;

FIG. 6 shows Bi₂WO₆、WO₃-Bi₂WO₆And different mass fractions of Ag₃PO₄-WO₃-Bi₂WO₆The EIS Nyquist plot of (A);

FIG. 7 shows the absorption spectrum of RhB on Ag3PO4-WO3-Bi2WO6 (0.3: 0.2: 1) heterojunction with irradiation time and Bi under visible light irradiation₂WO₆、WO₃-Bi₂WO₆Ag of different mass fractions₃PO4-WO₃-Bi₂WO₆And the degradation rate of RhB without catalyst;

FIG. 8 shows Bi₂WO₆、WO₃-Bi₂WO₆Ag of different mass fractions₃PO4-WO₃-Bi₂WO₆And the degradation rate of RhB versus cycle time.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.