阅读说明：本技术 一种棒状硫化镉复合钨酸铋z型异质结光催化材料的制备方法 (Preparation method of rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material ) 是由 李忠玉 张彤彤 孙卓 梁倩 周满 徐松 于 2019-11-14 设计创作，主要内容包括：本发明涉及一种棒状硫化镉复合钨酸铋Z型异质结光催化材料的制备方法,包括步骤：硫化镉纳米棒的制备、钨酸铋的制备和棒状硫化镉复合钨酸铋Z型异质结光催化材料的制备。本发明的有益效果是：该制备方法较为简单,制备条件容易控制,所制备的棒状硫化镉复合钨酸铋Z型异质结光催化材料具有无二次污染,光催化活性较好等优点,具有一定的应用价值。(The invention relates to a preparation method of a rodlike cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material, which comprises the following steps: the preparation method comprises the steps of preparing cadmium sulfide nanorods, preparing bismuth tungstate and preparing a rodlike cadmium sulfide composite bismuth tungstate Z-shaped heterojunction photocatalytic material. The invention has the beneficial effects that: the preparation method is simple, the preparation conditions are easy to control, and the prepared rodlike cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material has the advantages of no secondary pollution, good photocatalytic activity and the like, and has a certain application value.)

1. A preparation method of a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material is characterized by comprising the following steps:

(1) preparing cadmium sulfide nano rods: 4.66 g of Cd (NO)₃)₂·4H₂Dissolving O and 3.45 g of thiourea in 70 mL of ethylenediamine at the same time, and stirring at room temperature for 30 min; then transferring the mixture into a polytetrafluoroethylene-lined stainless steel autoclave, continuously reacting for 24 hours at 160 ℃, repeatedly washing the obtained product with deionized water and absolute ethyl alcohol after the autoclave is cooled to room temperature, and drying for 8 hours at 60 ℃;

(2) preparing bismuth tungstate: 0.97014g of Bi (NO) were weighed out₃)₃·5H₂O, 0.32985 g of Na₂WO₄·2H₂O, 0.05g CTAB, pouring the raw materials into a clean 100 mL beaker in sequence, adding 80 mL deionized water, and stirring at room temperature for 30 min; then transferring the mixture into a polytetrafluoroethylene stainless steel autoclave, and continuously reacting for 24 hours at 200 ℃; after the reaction is finished, cooling the reactant to room temperature, performing centrifugal separation, sequentially cleaning with water and ethanol, and drying the obtained product at 60 ℃ for 24 hours to obtain bismuth tungstate;

(3) preparing a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material: weighing cadmium sulfide prepared in the step (1) and bismuth tungstate prepared in the step (2), respectively adding the cadmium sulfide and the bismuth tungstate into 20 mL of absolute ethyl alcohol, and ultrasonically stirring for 1h to respectively obtain a cadmium sulfide suspension and a bismuth tungstate suspension; and dropwise adding the cadmium sulfide suspension into the bismuth tungstate suspension, carrying out ultrasonic treatment at room temperature for 1 hour, continuously stirring for 24 hours, then carrying out centrifugal collection, sequentially cleaning with water and ethanol, and finally drying the obtained product at 60 ℃ for 24 hours to obtain the rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material.

2. The preparation method of the rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material as claimed in claim 1, which is characterized in that: in the step (2), Bi (NO)₃)₃·5H₂O and Na₂WO₄·2H₂The molar ratio of O is 1: 1.

3. The preparation method of the rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material as claimed in claim 1, which is characterized in that: the mass ratio of the bismuth tungstate to the cadmium sulfide in the step (3) is 60 wt% -100 wt% respectively.

Technical Field

The invention belongs to the technical field of preparation and application of nano materials, and relates to a preparation method of a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material.

Background

Semiconductor photocatalysts have been extensively studied in many multidisciplinary areas of materials, chemistry, environment, etc. over the last few decades. Hundreds of semiconductor photocatalysts have been used in multifunctional applications, such as hydrogen (H)₂) Carbon dioxide emission reduction in production and energy fields, and sewage treatment and air purification in environmental pollution controlAnd (4) transforming. However, none of these semiconductor photocatalysts meets all the requirements of practical applications, such as high utilization of solar energy, high safety, high efficiency, high stability and low cost. Therefore, it is urgent to develop a photocatalytic material having excellent properties by optimizing the properties by coupling, adding a co-catalyst, constructing an appropriate heterojunction, and the like. The photocatalyst having a direct Z-type heterojunction shows considerably strong redox ability and hinders recombination of photogenerated carriers, compared to a conventional heterojunction. This is because the photogenerated electrons on the lower Conduction Band (CB) will recombine with the photogenerated holes on the higher Valence Band (VB), mimicking the photosynthesis of plants, to maintain the higher redox activity of the photogenerated carriers. Furthermore, the carrier mobility of a Z-type heterojunction is physically more feasible than a conventional heterojunction due to electrostatic attraction between photogenerated carriers.

Among various types of semiconductor photocatalysts under study, cadmium sulfide with a proper band gap (2.4 eV) is used for overcoming the defects of rapid recombination and photo-induced corrosion of photogenerated carriers, and many studies on modification are carried out on the aspect of research, including the construction of a heterojunction by compounding other semiconductor materials. Bismuth tungstate, which is a binary metal oxide and has a narrow band of 2.92 eV, has attracted increasing attention because the W atom in tungstate can significantly improve the conductivity as compared with a single metal oxide. The invention aims to synthesize a novel rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material by an in-situ hydrothermal method, and the prepared photocatalyst shows remarkably enhanced photocatalytic degradation efficiency due to slower recombination rate and prolonged service life of photon-generated carriers caused by fast electron injection from bismuth tungstate to cadmium sulfide.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: based on the problems, the invention provides a preparation method of a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material.

The technical scheme adopted by the invention for solving the technical problems is as follows: a preparation method of a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material comprises the following steps:

（1）preparing cadmium sulfide nano rods: 4.66 g of Cd (NO)₃)₂·4H₂O was dissolved in 70 mL of ethylenediamine together with 3.45 g of thiourea, and stirred at room temperature for 30 min. The mixture was then transferred to a stainless steel autoclave lined with polytetrafluoroethylene and allowed to react at 160 ℃ for 24 h, after the autoclave had cooled to room temperature, the resulting product was washed repeatedly with deionized water and absolute ethanol and dried at 60 ℃ for 8 h.

(2) Preparing bismuth tungstate: 0.97014g of Bi (NO) were weighed out₃)₃·5H₂O, 0.32985 g of Na₂WO₄·2H₂O, 0.05g CTAB, which were poured into a clean 100 mL beaker in sequence, 80 mL deionized water was added and stirred at room temperature for 30 min. The mixture was then transferred to a teflon stainless steel autoclave and the reaction was continued for 24 h at 200 ℃. After the reaction is finished, cooling the reactant to room temperature, performing centrifugal separation, sequentially cleaning with water and ethanol, and drying the obtained product at 60 ℃ for 24 hours to obtain the bismuth tungstate.

(3) Preparing a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material: and (3) weighing the cadmium sulfide prepared in the step (1) and the bismuth tungstate prepared in the step (2), respectively adding the cadmium sulfide and the bismuth tungstate into 20 mL of absolute ethyl alcohol, and ultrasonically stirring for 1h to respectively obtain a cadmium sulfide suspension and a bismuth tungstate suspension. Then dropwise adding the cadmium sulfide suspension into the bismuth tungstate suspension, and continuously stirring for 24 hours after carrying out ultrasonic treatment for 1 hour at room temperature. And then centrifugally collecting, sequentially cleaning with water and ethanol, and finally drying the obtained product at 60 ℃ for 24 hours to obtain the rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material.

Further, in the step (2), Bi (NO)₃)₃·5H₂O and Na₂WO₄·2H₂The molar ratio of O is 1: 1.

Further, the mass ratio of bismuth tungstate to cadmium sulfide in the step (3) is 60 wt% -100 wt% respectively.

The invention has the beneficial effects that: the preparation method is simple, the preparation conditions are easy to control, and the prepared rodlike cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material has the advantages of no pollution, good photocatalytic activity and the like, and has a certain practical application value.

Drawings

The invention is further described below with reference to the accompanying drawings.

FIG. 1 is a scanning electron microscope image of a rod-shaped cadmium sulfide composite bismuth tungstate Z-type heterojunction photocatalytic material prepared in example 1 of the present invention;

FIG. 2 is an X-ray diffraction pattern of the rod-shaped cadmium sulfide-bismuth tungstate composite Z-type heterojunction photocatalytic material prepared in example 1 of the present invention;

FIG. 3 is a diagram showing the photocatalytic activity of degraded rhodamine B (RhB) of the rodlike cadmium sulfide-bismuth tungstate Z-type heterojunction photocatalytic material prepared in example 1 of the present invention.

Detailed Description

The invention will now be further illustrated by reference to specific examples, which are intended to be illustrative of the invention and are not intended to be a further limitation of the invention.