阅读说明：本技术 一种BiOI/MoS2异质结复合光催化剂及其制备方法和应用 (BiOI/MoS2Heterojunction composite photocatalyst and preparation method and application thereof ) 是由 郝雷 鞠鹏 张雨 翟晓凡 曹为 蒋凤华 李景喜 孙承君 于 2020-07-29 设计创作，主要内容包括：本发明属于光催化领域,具体涉及一种BiOI/MoS<Sub>2</Sub>异质结复合光催化剂及其制备方法和应用。BiOI/MoS<Sub>2</Sub>异质结复合光催化剂由MoS<Sub>2</Sub>和BiOI组成,其中,BiOI与MoS<Sub>2</Sub>的质量比为0.02:1～0.1:1。BiOI/MoS<Sub>2</Sub>异质结复合光催化剂采用两步操作获得,首先通过水热合成法制备花状MoS<Sub>2</Sub>,然后在超声条件下分散剥离,并加入Bi(NO<Sub>3</Sub>)<Sub>3</Sub>·5H<Sub>2</Sub>O和KI,最终在水热条件下得到BiOI/MoS<Sub>2</Sub>异质结复合光催化剂。本发明构建了具有可见光响应的BiOI/MoS<Sub>2</Sub>异质结,加速了光生载流子的分离,在可见光下具有高效的光催化活性和稳定性,对水体中的有害微生物和染料污染物具有高效的杀灭和降解效果,在水体净化和海洋防污等领域具有很好的实用价值和潜在的应用前景。(The invention belongs to the field of photocatalysis, and particularly relates to a BiOI/MoS 2 A heterojunction composite photocatalyst and a preparation method and application thereof. BiOI/MoS 2 Heterojunction composite photocatalyst composed of MoS 2 And BiOI, wherein the BiOI and MoS 2 The mass ratio of (A) to (B) is 0.02: 1-0.1: 1. BiOI/MoS 2 The heterojunction composite photocatalyst is obtained by two-step operation, and flower-shaped MoS is prepared by hydrothermal synthesis method 2 Then dispersed and stripped under ultrasonic condition, and Bi (NO) is added 3 ) 3 ·5H 2 O and KI, and finally obtaining the BiOI/MoS under the hydrothermal condition 2 A heterojunction composite photocatalyst. The invention constructs the visible light responseBiOI/MoS of 2 The heterojunction accelerates the separation of photon-generated carriers, has high-efficiency photocatalytic activity and stability under visible light, has high-efficiency killing and degrading effects on harmful microorganisms and dye pollutants in water, and has good practical value and potential application prospect in the fields of water purification, marine antifouling and the like.)

1. BiOI/MoS₂The heterojunction composite photocatalyst is characterized in that the BiOI/MoS₂The heterojunction composite photocatalyst consists of bismuth oxyiodide BiOI and molybdenum disulfide MoS₂Composition of BiOI and MoS₂The mass ratio of (A) to (B) is 0.02: 1-0.1: 1.

2. The BiOI/MoS of claim 1₂The heterojunction composite photocatalyst is characterized in that the BiOI/MoS₂The preparation method of the heterojunction composite photocatalyst comprises the following steps:

1)MoS₂the preparation of (1):

sequentially adding ammonium molybdate NH into ultrapure water₄)₆Mo₇O₂₄·5H₂O-Thioacetamide CH₄N₂S, transferring the dissolved solution into a high-pressure reaction kettle with a polytetrafluoroethylene lining, and putting the high-pressure reaction kettle into an electric heating constant-temperature air blast drying oven for heat treatment at 200-240 ℃ for 12-20 h; then cooling the reaction kettle to room temperature, and obtaining the MoS with the flower-like structure through suction filtration, washing and drying₂；

2)BiOI/MoS₂Preparing a heterojunction composite photocatalyst:

the MoS obtained in the step 1) is treated₂Adding into ethylene glycol, adding polyvinylpyrrolidone PVP and bismuth nitrate Bi (NO)₃)₃·5H₂O, performing ultrasonic dispersion to obtain a dispersion liquid A; adding potassium iodide KI into ultrapure water to be completely dissolved to obtain a suspension B; dropwise adding the dispersion liquid B into the suspension liquid A, continuously stirring for 30-90 min, transferring the mixed liquid into a high-pressure reaction kettle with a polytetrafluoroethylene lining, and putting the high-pressure reaction kettle into an electric heating constant-temperature blast drying oven for heat treatment at the temperature of 140-200 ℃ to 24 ℃48 h; after the reaction is finished, cooling the reaction kettle to room temperature, and performing suction filtration, washing and drying to obtain the BiOI/MoS₂A heterojunction composite photocatalyst.

3. The BiOI/MoS of claim 2₂The heterojunction composite photocatalyst is characterized in that (NH) in the step 1)₄)₆Mo₇O₂₄·5H₂O and CH₄N₂The molar ratio of S is 1: 20-30.

4. The BiOI/MoS of claim 2₂The heterojunction composite photocatalyst is characterized in that the ultrasonic dispersion time in the step 2) is 4-8 hours.

5. The BiOI/MoS of claim 2₂The heterojunction composite photocatalyst is characterized in that Bi (NO) in the step 2)₃)₃·5H₂The ratio of the amount of O to the amount of KI material was 3: 1.

6. The BiOI/MoS of any one of claims 1 to 5₂Application of the heterojunction composite photocatalyst in degradation of dye.

7. The use of claim 6, wherein the dye is rhodamine B (RhB).

8. The BiOI/MoS of any one of claims 1 to 5₂The application of the heterojunction composite photocatalyst in killing harmful microorganisms.

9. The use of claim 8, wherein said harmful microorganism is pseudomonas aeruginosa (p.

Technical Field

The invention belongs to the technical field of photocatalysis, and particularly relates to a BiOI/MoS₂A heterojunction composite photocatalyst and a preparation method and application thereof.

Background

As is well known, global environmental pollution is becoming more serious, and water pollution has become a major problem to human beings. In the ocean, biofouling issues have also limited human exploration of the ocean. To overcome this problem, scientists have conducted a great deal of research. The semiconductor material provides a new method for solving the problems. Semiconductor materials are widely used in human society, and their use in various fields is also being explored. Since the discovery of TiO by Fujishima et al₂Since the photocatalytic performance, more and more photocatalyst materials are developed and applied^[1,2]. Among them, bismuth oxyiodide (BiOI) is a promising photocatalytic material due to its narrow band gap width (1.7-1.9eV) and two-dimensional layered structure of graphene-like^[3]. In addition, the BiOI has the advantages of being inexpensive and easy to manufacture, but the BiOI also has some disadvantages to overcome, such as a strong recombination capability of electrons and holes in the BiOI due to a too small band gap. Furthermore, the conduction band position of the BiOI is more positive than the reduction potential of hydrogen, which prevents the generation of active groups. These factors have all hindered the further development of the BiOI material.

Therefore, in order to improve these defects and thereby enhance the photocatalytic activity of the BiOI, it is necessary to appropriately modify the BiOI.

[1]A.Fujishima,K.Honda.Electrochemical photolysis of water at asemiconductor electrode.Nature,1972,238,37-38.

[2]S.N.Frank,A.J.Bard.Heterogeneous photocatalytic oxidation ofcyanide and sulfite in aqueous solutions at semiconductorpowders.J.Phys.Chem.,1977,81,1484-1488.

[3]J.Su,X.X.Zou,G.D.Li,X.Wei,C.Yan,Y.N.Wang,J.Zhao,L.J.Zhou,J.S.Chen.Macroporous V₂O₅-BiVO₄composites:effect of heterojunction on thebehavior of photogenerated charges.J.Phys.Chem.C,2011,115,8064-8071。

Disclosure of Invention

The invention aims to provide a BiOI/MoS aiming at the problems in the prior art₂The heterojunction composite photocatalyst, the preparation method and the application thereof make up for the defects of the prior art.

The BiOI/MoS provided by the invention₂A composite photocatalyst is prepared from bismuth oxyiodide (BiOI) and molybdenum disulfide (MoS)₂) Composition of BiOI and MoS₂The mass ratio of (A) to (B) is 0.02: 1-0.1: 1.

Provided BiOI/MoS₂The preparation method of the heterojunction composite photocatalyst comprises the following steps:

1)MoS₂the preparation of (1):

ammonium molybdate ((NH) is added into ultrapure water in turn₄)₆Mo₇O₂₄·5H₂O) and thioacetamide (CH)₄N₂S), magnetically stirring until the solution is completely dissolved, transferring the dissolved solution into a high-pressure reaction kettle with a polytetrafluoroethylene lining, and putting the high-pressure reaction kettle into an electric heating constant-temperature air blast drying oven for heat treatment at 200-240 ℃ for 12-20 hours; then cooling the reaction kettle to room temperature, and obtaining the MoS with the flower-like structure through suction filtration, washing and drying at 60 DEG C₂；

2)BiOI/MoS₂Preparing a heterojunction composite photocatalyst:

the MoS obtained in the step 1) is treated₂Adding into ethylene glycolIn the above-mentioned reaction solution, polyvinylpyrrolidone (PVP) and bismuth nitrate (Bi (NO) are added₃)₃·5H₂O), ultrasonic dispersion to obtain a dispersion liquid A; adding potassium iodide (KI) into ultrapure water to be completely dissolved to obtain a suspension B; dropwise adding the dispersion liquid B into the suspension liquid A under magnetic stirring, continuously carrying out magnetic stirring for 30-90 min, transferring the mixed liquid into a high-pressure reaction kettle with a polytetrafluoroethylene lining, and putting the high-pressure reaction kettle into an electric heating constant-temperature air-blast drying oven for heat treatment at 140-200 ℃ for 24-48 h; after the reaction is finished, cooling the reaction kettle to room temperature, and obtaining the BiOI/MoS after suction filtration, washing and drying for 6h at 60 DEG C₂A heterojunction composite photocatalyst.

(NH) in said step 1)₄)₆Mo₇O₂₄·5H₂O and CH₄N₂The molar ratio of S is 1: 20-30;

the ultrasonic dispersion time in the step 2) is 4-8 h;

bi (NO) in the step 2)₃)₃·5H₂The ratio of the amount of O to the amount of KI material was 3: 1.

In another aspect, the invention also provides BiOI/MoS₂The application of the heterojunction composite photocatalyst in degrading dyes;

the dye is rhodamine B (RhB);

in another aspect, the invention also provides BiOI/MoS₂The application of the heterojunction composite photocatalyst in killing harmful microorganisms.

The harmful microorganism is pseudomonas aeruginosa (P.

The invention has the beneficial effects that:

the invention is realized by combining BiOI and MoS₂Compounding, constructing a composite material with a heterostructure, accelerating the separation of photon-generated carriers on the surface of the composite material, further improving the photocatalytic performance, and carrying out the treatment on the BiOI and the MoS₂The practical application of the two materials in the field of photocatalysis is of great significance.

(1) The invention adopts the simple hydrothermal synthesis method to prepare the BiOI/MoS₂The heterojunction composite photocatalyst can effectively degrade RhB and inactivate P.aeruginosa;

(2) BiOI/MoS prepared by the invention₂The heterojunction composite photocatalyst has good visible light absorption performance and photocatalytic performance, and the photocatalytic activity is compared with that of BiOI and MoS₂Are all obviously improved;

(3) MoS prepared by the invention₂/Bi₂WO₆The heterojunction composite photocatalyst has good stability and reusability;

(4) BiOI/MoS prepared by the invention₂The heterojunction composite photocatalyst has a type II heterostructure, accelerates the separation of photon-generated carriers, improves the visible light catalytic activity, and has good practical value and potential application prospect in the fields of water purification, marine antifouling and the like.

Drawings

FIG. 1 is an XRD pattern of a sample prepared according to the present invention, wherein the abscissa is 2 θ (angle) and the unit is degree; intensity on the ordinate, in a.u. (absolute units);

FIG. 2 is a Field Emission Scanning Electron Microscope (FESEM) photograph of a sample prepared according to the present invention: (A) MoS₂，(B)BiOI，(C,D)BiOI/MoS₂；

FIG. 3 is a graph of the ultraviolet-visible diffuse reflectance spectrum (UV-DRS) of a sample prepared according to the present invention, wherein the abscissa is the Wavelength (Wavelength) in nm (nanometers) and the ordinate is the Absorbance (Absorbance) in a.u (absolute units);

FIG. 4 shows the variation of RhB concentration with Time (A) and the variation of bacterial survival with Time (B) in the photocatalytic degradation reaction of Pseudomonas aeruginosa in the sample prepared by the present invention, wherein the abscissa of the graph A is Time in min and the ordinate is C_t/C₀，C₀Initial concentration of RhB before reaction initiation, C_tThe RhB concentration at reaction time t; on the graph B, the ordinate represents the survivability ratio in%.

Detailed Description

The present invention is further illustrated by the following specific examples, which are intended to provide a more complete understanding of the invention by one of ordinary skill in the art, and are not intended to be limiting in any way.