BiOCl photocatalytic material as well as preparation method and application thereof

Abstract

The invention relates to the technical field of BiOCl photocatalytic material preparation and water pollution degradation, in particular to a BiOCl photocatalytic material and a preparation method and application thereof.The preparation method comprises the following steps that soluble Bi salt is dissolved in a solvent and subjected to ultrasonic treatment, a first solution is obtained, soluble chloride salt is dissolved in the solvent and stirred, and a second solution is obtained; adding the second solution into the first solution, stirring and mixing at room temperature, carrying out an ultrasonic microwave chemical reaction to obtain a suspension, and carrying out post-treatment on the suspension to obtain the BiOCl photocatalytic material. The photocatalytic material is used for effectively removing mercury ions in a water body.

Description

Technical Field

[0001] The invention relates to the technical field of BiOCl photocatalytic material preparation and water pollution degradation, and in particular to a BiOCl photocatalytic material and a preparation method and application thereof. Background Art

[0002] In the past few decades, the rapid economic development and accelerated urbanization have brought about a large number of sewage discharge and water pollution problems. Common water pollutants include organic pollutants, inorganic pollutants, nutrients, suspended solids, pathogenic microorganisms, etc. Among them, organic pollutants in water refer to carbon-containing compounds, which mainly come from industrial wastewater, agricultural discharge and domestic sewage, posing a threat to water ecology and human health. These pollutants are numerous and complex, often with strong stability and toxicity, difficult to degrade naturally, and may accumulate in organisms, leading to eutrophication and biological toxicity of water bodies. The difficulties faced in treating these pollutants include their difficulty in degradation, high treatment costs, by-product generation, complexity of treatment technology selection and regulatory requirements. Meeting these challenges usually requires a combination of multiple technologies such as biological treatment, chemical redox, adsorption, membrane separation technology and advanced oxidation methods to ensure effective removal of pollutants and protect the water environment and human health.

[0003] Traditional sewage treatment methods have some disadvantages. First, they may produce secondary pollution. For example, the sludge produced by chemical precipitation method needs additional treatment, otherwise it may cause environmental problems. Secondly, traditional treatment methods often require high energy consumption. For example, the high-load activated sludge method requires a lot of energy for air blowing and heating, which increases operating costs. In addition, these methods have limited efficiency in treating difficult-to-degrade pollutants, and the maintenance and operating costs are also high. Especially when the treatment scale is expanded, the maintenance costs will increase significantly. In addition, traditional facilities usually occupy a large area, which is not conducive to areas with tight land resources. At the same time, some treatment processes take a long time and may not be suitable for real-time or rapid treatment needs. The advantages of photocatalysis in treatment efficiency, environmental protection and energy consumption make it a powerful supplement to traditional methods, especially when treating difficult-to-degrade pollutants.

[0004] Photocatalytic degradation uses photocatalysts (such as titanium dioxide) to accelerate the degradation of organic pollutants under light, and has significant advantages. First, it can efficiently degrade a variety of organic pollutants, including difficult-to-degrade chemicals, while avoiding secondary pollution. Second, compared with traditional chemical treatment methods, photocatalytic degradation is energy-saving and environmentally friendly because it mainly uses sunlight or ultraviolet light sources. This technology is widely applicable to the treatment of a variety of water bodies and wastewater, and photocatalysts are generally non-toxic, stable and reusable, thereby reducing material costs and processing expenses. These characteristics make photocatalytic degradation a promising sustainable water treatment technology.

[0005] BiOCl has significant applications and advantages in the photocatalytic degradation process. As a photocatalyst, it mainly uses its excellent light absorption ability and large specific surface area to improve the degradation efficiency. BiOCl can effectively generate photogenerated electron and hole pairs under visible light, thereby enhancing the degradation ability of organic pollutants. Its advantages also include high chemical stability and corrosion resistance, which makes it have a long service life in practical applications. In addition, BiOCl has a moderate band gap width, which enables it to work effectively in a wide spectral range, further improving its photocatalytic performance.

[0006] Existing methods for preparing BiOCl photocatalytic materials include solvothermal method, precipitation method, hydrothermal method, solid phase reaction method and sol-gel method, but these methods have the problems of requiring high temperature and high pressure, complex operation, uneven products, high requirements on raw material purity and low photocatalytic performance of the prepared materials during the preparation process. Summary of the invention

[0007] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a BiOCl photocatalytic material and a preparation method and application thereof. The present invention utilizes microwave radiation as an energy source and ultrasound to promote mixing and mass transfer, thereby achieving efficient synthesis of BiOCl in a short time. The BiOCl photocatalytic material prepared by the ultrasound-microwave synergistic method exhibits excellent photocatalytic performance.

[0008] In order to solve the above technical problems, the present invention adopts the following technical solutions:

[0009] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0010] Dissolving a soluble Bi salt in a first solvent, and subjecting to ultrasonic treatment to obtain a first solution, and dissolving a soluble chloride salt in a second solvent, and stirring to obtain a second solution;

[0011] The second solution is added to the first solution, stirred and mixed at room temperature, and ultrasonic microwave chemical reaction is performed to obtain a suspension, and the suspension is post-treated to obtain a BiOCl photocatalytic material.

[0012] The present invention prepares BiOCl photocatalytic material by ultrasonic-microwave synergistic method, which exhibits excellent photocatalytic performance. Microwave radiation is used as an energy source to rapidly heat the reaction system. Ultrasonic waves promote mixing and mass transfer, and efficient synthesis of BiOCl can be achieved at a relatively low temperature in a short time, thereby reducing the risk of decomposition of heat-sensitive materials. In addition, ultrasonic-microwave synergistic effect improves product selectivity, reduces by-product generation, and improves purity. Meanwhile, microwaves provide uniform temperature distribution, and ultrasonic waves promote mixing, thereby improving experimental repeatability. The preparation method of the present invention is simple and easy to implement, does not require expensive equipment and harsh production conditions, has mild reaction conditions, can be rapidly synthesized, has good uniformity of the product, and the prepared material is non-toxic, tasteless, pollution-free, and can be reused, and is suitable for removing organic pollutants from industrial wastewater.

[0013] In a preferred embodiment of the present invention, the ultrasonic frequency is 20KHz to 25KHz.

[0014] In a preferred embodiment of the present invention, the microwave power is 160W to 480W.

[0015] In a preferred embodiment of the present invention, the ultrasonic microwave chemical reaction time is 0.5h to 3h.

[0016] In a preferred embodiment of the present invention, the ultrasonic microwave chemical reaction temperature is 80°C to 120°C.

[0017] In a preferred embodiment of the present invention, the usage ratio of the soluble Bi salt to the first solvent is 0.01 mol:10 mL to 25 mL, the soluble Bi salt is Bi(NO3)3·5H2O, and the first solvent is ethylene glycol, ethanol or methanol.

[0018] In a preferred embodiment of the present invention, the usage ratio of the soluble chloride salt to the second solvent is 0.012 mol:10 mL to 25 mL, the soluble chloride salt is NaCl or KCl, and the second solvent is ethylene glycol, ethanol or methanol.

[0019] In a preferred embodiment of the present invention, the volume ratio of the second solution to the first solution is 1:1.

[0020] Another object of the present invention is to provide a BiOCl photocatalytic material prepared by any of the preparation methods described above.

[0021] The third object of the present invention is to provide an application of the above-mentioned BiOCl photocatalytic material in catalytic degradation of organic pollutants.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention prepares BiOCl photocatalytic materials through an ultrasonic-microwave synergistic method and exhibits excellent photocatalytic performance. Microwave radiation is used as an energy source to rapidly heat the reaction system. Ultrasonic waves promote mixing and mass transfer, and efficient synthesis of BiOCl can be achieved at a relatively low temperature in a short time, thereby reducing the risk of decomposition of heat-sensitive materials. In addition, the ultrasonic-microwave synergistic effect improves product selectivity, reduces by-product generation, and improves purity. Meanwhile, microwaves provide uniform temperature distribution, and ultrasonic waves promote mixing, thereby improving the repeatability of the experiment. The preparation method of the present invention is simple and easy to implement, does not require expensive equipment and harsh production conditions, has mild reaction conditions, is rapidly synthesized, and has good uniformity of the product. The prepared material is non-toxic, tasteless, pollution-free, and can be reused, and is suitable for the removal of organic pollutants in industrial wastewater.

[0024] 2. The present invention uses microwave radiation as an energy source and ultrasound to promote mixing and mass transfer, achieving efficient synthesis of BiOCl in a short time. Compared with traditional microwave and heat treatment methods, this method has higher energy utilization efficiency and more uniform temperature distribution, thereby effectively controlling the grain size and morphology of the product. The synthesized BiOCl photocatalyst particles have a nanometer-level particle size. This tiny particle size not only increases the specific surface area of ​​the material, but also significantly improves its photocatalytic activity. In the organic pollutant degradation experiment, the synthesized BiOCl photocatalyst exhibited excellent photocatalytic performance and was able to quickly and effectively degrade a variety of organic pollutants under visible light irradiation. This method not only improves the catalytic efficiency of BiOCl, but also demonstrates its wide application potential in the field of environmental remediation. Through the ultrasonic-microwave synergistic synthesis method, the present invention not only optimizes the photocatalytic performance of BiOCl, but also provides an efficient and economical synthesis route for its large-scale application.

[0025] 3. The present invention utilizes ultrasonic-microwave synergistic technology to complete the synthesis of BiOCl in a very short time. Microwave heating provides uniform energy distribution, significantly shortens the synthesis time, and improves production efficiency. This efficient synthesis method reduces energy consumption, making the overall production process more economical and environmentally friendly; the reaction can accurately control the temperature and pressure of the reaction during the synthesis process, thereby effectively controlling the particle size of the BiOCl photocatalyst. The generated nanoscale particles have a large specific surface area, which enhances the activity of the photocatalyst, so that it exhibits higher catalytic efficiency and reaction rate when degrading organic pollutants; the synthesized BiOCl photocatalyst exhibits excellent photocatalytic performance. Its small particle size and optimized crystal structure significantly improve the activity of the photocatalyst under visible light, enabling it to efficiently degrade various organic pollutants. This performance improvement gives it broad potential in environmental remediation applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1This is a physical picture of the BiOCl photocatalyst material prepared in Example 1 of the present invention.

[0027] Figure 2 This is the XRD spectrum of the BiOCl photocatalyst material prepared in Example 1 of the present invention.

[0028] Figure 3 (a) high-magnification and (b) low-magnification TEM spectra of the BiOCl photocatalyst material prepared in Example 1 of the present invention.

[0029] Figure 4 This is the light response diagram of the BiOCl photocatalyst material prepared in Example 1 of the present invention. DETAILED DESCRIPTION

[0030] The following is a detailed description of the technical solutions in the embodiments of the present invention in combination with the preferred embodiments and the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] It should be noted that all professional terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the scope of protection of the present invention. Unless otherwise specifically stated, various raw materials, reagents, instruments and equipment used in the following embodiments of the present invention can be purchased from the market or prepared by existing methods.

[0032] Bi-based materials have important applications in photocatalytic degradation. They are widely used in the development of photocatalysts because Bi-based materials such as Bi2O3 and BiVO4 show excellent photocatalytic performance and can effectively degrade organic pollutants in water. Among them, Bi2O3 has been widely studied and applied to the degradation of organic pollutants due to its good photocatalytic activity and wide light absorption range under visible light; Bi2WO6 is used to treat organic pollutants in water such as phenol and methyl orange due to its high photocatalytic activity and stability under visible light; Bi2S3 shows excellent photocatalytic performance under near-infrared light and is widely used in sewage treatment and antibacterial fields; Bi2O2CO3 is used to degrade a variety of organic pollutants such as methyl orange and methylene blue due to its high photocatalytic activity, especially under visible light. Its advantages include wide spectrum absorption capacity, good photocharge separation efficiency and high stability. These materials can generate strong photogenerated carriers under visible light irradiation, which improves the photocatalytic efficiency, and due to their stability, they can maintain efficient catalytic performance under various environmental conditions. Overall, Bi-based materials have performed well in the fields of environmental protection and wastewater treatment due to their excellent photocatalytic performance.

[0033] At present, there are several ways to improve the performance of BiOCl in the photocatalytic degradation process. First, doping with different elements (such as N, S, Fe, etc.) can adjust its band structure and expand the light response range, thereby improving the photocatalytic activity. Secondly, preparing BiOCl into nanosize can increase the specific surface area, improve the separation efficiency of photogenerated electrons and holes, and further improve the catalytic performance. Composite is another effective method. Composite with other semiconductor materials (such as TiO2, ZnO, etc.) to form a heterojunction can enhance the separation efficiency of photogenerated electron-hole pairs, thereby improving the photocatalytic activity. In addition, through surface modification, such as surface coating or doping treatment, the surface properties of BiOCl can be improved, and its adsorption capacity and photocatalytic performance for pollutants can be enhanced. Finally, the use of photosensitizers or light absorbers to expand the absorption range of BiOCl for visible light can also improve its photocatalytic effect under visible light. The combination of these methods can significantly improve the photocatalytic degradation ability of BiOCl.

[0034] Based on the reported hydrothermal synthesis of BiOCl photocatalyst, this application develops an innovative ultrasonic-microwave synergistic method for preparing BiOCl photocatalyst, which significantly improves the performance of the photocatalyst and the microstructure of the material. Ultrasonic-microwave synergistic reaction synthesis has significant advantages over traditional ultrasonic and microwave methods. First, it can significantly increase the reaction rate, ultrasound promotes mixing and mass transfer, and microwaves quickly heat the reaction system. Secondly, this combination can react efficiently at lower temperatures and reduce the risk of decomposition of heat-sensitive materials. In addition, the synergistic effect improves product selectivity, reduces by-product generation, and improves purity. At the same time, microwaves provide uniform temperature distribution and ultrasound promotes mixing, thereby improving the repeatability of the experiment. In the preparation of nanomaterials, this combination helps to control particle size and morphology and improve material properties.

[0035] The present invention uses microwave radiation as an energy source and ultrasound to promote mixing and mass transfer. The method achieves efficient synthesis of BiOCl in a short time. Compared with traditional microwave and heat treatment methods, this method has higher energy utilization efficiency and more uniform temperature distribution, thereby effectively controlling the grain size and morphology of the product. The synthesized BiOCl photocatalyst particles have a nanometer-level particle size. This tiny particle size not only increases the specific surface area of ​​the material, but also significantly improves its photocatalytic activity. In the organic pollutant degradation experiment, the synthesized BiOCl photocatalyst exhibits excellent photocatalytic performance and can quickly and effectively degrade a variety of organic pollutants under visible light irradiation. This method not only improves the catalytic efficiency of BiOCl, but also demonstrates its wide application potential in the field of environmental remediation. Through the ultrasonic-microwave synergistic synthesis method, the present invention not only optimizes the photocatalytic performance of BiOCl, but also provides an efficient and economical synthesis route for its large-scale application.

[0036] Studies have shown that the material has a stable structure, good removal efficiency for organic pollutants in water, fast removal and high removal rate, many recycling times, and no secondary pollution. The raw materials required for this process are abundant, the preparation process is simple, and the cost is saved. The catalyst has certain acid and alkali resistance and is easy to use, which is suitable for the removal of organic pollutants in industrial wastewater.

[0037] Example 1

[0038] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0039] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0040] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0041] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 240 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0042] Example 2

[0043] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0044] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 10 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0045] (2) Dissolve 0.012 mol of NaCl in 10 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0046] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 240 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0047] Example 3

[0048] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0049] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 20 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0050] (2) Dissolve 0.012 mol of NaCl in 20 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0051] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 240 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0052] Example 4

[0053] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0054] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 25 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0055] (2) Dissolve 0.012 mol of NaCl in 25 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0056] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 240 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0057] Example 5

[0058] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0059] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0060] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0061] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 160 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0062] Example 6

[0063] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0064] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0065] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0066] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 320 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0067] Example 7

[0068] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0069] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0070] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0071] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C., with an ultrasonic frequency of 25 kHz and a microwave power of 400 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C. for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0072] Example 8

[0073] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0074] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0075] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0076] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 110 ° C, with an ultrasonic frequency of 25 kHz and a microwave power of 480 W. After reacting for 1 h, it was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0077] Example 9

[0078] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0079] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0080] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0081] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in an ultrasonic microwave chemical reactor at 80 ° C, with an ultrasonic frequency of 20 kHz and a microwave power of 240 W. After reacting for 0.5 h, it was cooled to room temperature. The resulting suspension was centrifuged, and the resulting solid was washed three times with deionized water and anhydrous ethanol respectively, and then dried in a vacuum drying oven at 60 ° C for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0082] Example 10

[0083] A method for preparing a BiOCl photocatalyst comprises the following steps:

[0084] (1) Dissolve 0.01 mol of Bi(NO3)3·5H2O in 15 mL of ethylene glycol and sonicate for 1 h to form a transparent solution A.

[0085] (2) Dissolve 0.012 mol of NaCl in 15 mL of ethylene glycol and stir until it is completely dissolved to form a transparent solution B.

[0086] (3) Solution B was slowly poured into solution A. At this time, the solution turned milky white. After stirring at room temperature for 30 min, the mixture was transferred to a 100 mL reaction bottle and placed in a 120°C ultrasonic microwave chemical reactor with an ultrasonic frequency of 40 kHz and a microwave power of 240 W. After reacting for 3 h, the mixture was cooled to room temperature and the resulting suspension was centrifuged. The resulting solid was washed three times with deionized water and anhydrous ethanol, respectively, and then dried in a 60°C vacuum drying oven for 12 h. The resulting solid was ground to obtain BiOCl nanosheets.

[0087] The instruments and characterization methods used in the present invention are as follows:

[0088] (1) X-ray diffractometer (XRD) uses German Bruker D8ADVANCE wide-angle X-ray diffractometer, Cu target Scanning range: 0~10°.

[0089] (2) Transmission electron microscopy (SEM) was used to record the scanned sample images using JEM2100PLUS.

[0090] (3) The electrochemical workstation is Chenhua CHI760E.

[0091] The testing process is as follows:

[0092] 50 mL of a standard solution of organic pollutants (dyes, drugs, etc.) of a certain concentration was prepared and placed in the photocatalytic cell. 20 mg of BiOCl photocatalyst was added and the pH was adjusted. The solution was stirred for 30 min in the dark to eliminate adsorption. The solution was reacted for 1 h under a xenon lamp with a light source of 300 W. Samples were taken every 10 min and filtered to determine the degradation efficiency by testing the ultraviolet absorption peak of the organic pollutants.

[0093] When testing the photoelectric response of the photocatalyst, 10 mg of BiOCl photocatalyst was dissolved in 1 mL of ethanol and ultrasonicated for 1 h. The completely ultrasonically dispersed solution was dropped onto a 1 cm*3 cm FTO sheet. The photoresponse current of the photocatalyst was tested under a xenon lamp light source of 300 W and an electrolyte of NaSO4 using a three-electrode system, with a Pt sheet electrode as the counter electrode and an Ag / AgCl electrode as the reference electrode.

[0094] The chemical reagents used in the embodiments of the present invention are provided by Sinopharm Chemical Reagent Co., Ltd.

[0095] Results Analysis

[0096] Figure 1 This is a physical picture of the BiOCl photocatalyst material prepared in Example 1 of the present invention. Figure 2 The XRD spectrum of the BiOCl photocatalyst material prepared in Example 1 of the present invention shows clear diffraction peaks by comparison with the standard card (PDF#06-0249), and all peak positions are highly consistent with the standard values ​​of BiOCl. This shows that the synthesized BiOCl material has good crystallinity. In addition, no impurity peaks appear in the spectrum, which further verifies the selectivity of the reaction and the purity of the synthesis process. These results show that the ultrasonic microwave method used can effectively prepare high-purity BiOCl photocatalytic materials, laying a solid foundation for its further research in photocatalytic applications.

[0097] Figure 3 (a) High-magnification and (b) low-magnification TEM spectra of the BiOCl photocatalyst material prepared in Example 1 of the present invention. The analysis results show that the synthesized BiOCl mainly presents a uniform nanorod-like structure with a width range of 10nm to 20nm and a length range of 50nm to 70nm. This structural feature shows that the morphology and size of BiOCl can be effectively controlled during the synthesis process, and the uniform nanorod-like structure helps to increase the surface area of ​​the photocatalytic reaction, thereby improving its photocatalytic performance. The clarity and consistency of the TEM image further verify the effectiveness and repeatability of the synthetic method adopted, and provide an important morphological basis for further research on BiOCl in photocatalytic applications.

[0098] Figure 4The light response diagram of the BiOCl photocatalyst material prepared in Example 1 of the present invention was tested using a 300W xenon lamp (PLS-SXE300C: wavelength range: 420nm≤λ≤780nm, light intensity: 300mW / cm 2 ) as the light source, the photocurrent response curve of BiOCl was tested in a three-electrode system, the FTO photoelectrode loaded with 20mg BiOCl was used as the anode, the Pt sheet was used as the counter electrode, and the Ag / AgCl electrode was used as the reference electrode. The test was conducted at a voltage of 0.7V vs.Ag / AgCl for 120s, and the light source was blocked at intervals of 10s to determine the photoresponse of the material. As can be seen from the figure, the maximum photocurrent response of BiOCl can reach 0.27mA / cm 2 , and showed good stability. This result shows that BiOCl material has excellent photoelectric conversion performance under light, and can effectively convert light energy into electrical energy. The stable photocurrent response also reflects the potential advantages of this material in photocatalytic applications, indicating that it has good application prospects in the field of optoelectronics. These performance characteristics provide strong support for further exploring the application of BiOCl in photocatalysis and photoelectrochemical reactions.

[0099] In summary, the present invention utilizes ultrasonic-microwave synergistic technology to complete the synthesis of BiOCl in a very short time. Microwave heating provides uniform energy distribution, significantly shortens the synthesis time, and improves production efficiency. This efficient synthesis method reduces energy consumption, making the overall production process more economical and environmentally friendly; the reaction can accurately control the temperature and pressure of the reaction during the synthesis process, thereby effectively controlling the particle size of the BiOCl photocatalyst. The generated nanoscale particles have a large specific surface area, which enhances the activity of the photocatalyst, so that it exhibits higher catalytic efficiency and reaction rate when degrading organic pollutants; the synthesized BiOCl photocatalyst exhibits excellent photocatalytic performance. Its small particle size and optimized crystal structure significantly improve the activity of the photocatalyst under visible light, enabling it to efficiently degrade various organic pollutants. This performance improvement gives it broad potential in environmental remediation applications.

[0100] It should be noted that when the present invention involves a numerical range, it should be understood that the two endpoints of each numerical range and any value between the two endpoints can be selected. Since the steps and methods used are the same as those in the embodiments, in order to avoid redundancy, the present invention describes a preferred embodiment. Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they know the basic creative concept. Therefore, the attached claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0101] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for preparing a BiOCl photocatalytic material, characterized in that: The following steps are involved: Dissolving a soluble Bi salt in a first solvent, and subjecting to ultrasonic treatment to obtain a first solution, and dissolving a soluble chloride salt in a second solvent, and stirring to obtain a second solution; The second solution is added to the first solution, stirred and mixed at room temperature, and ultrasonic microwave chemical reaction is performed to obtain a suspension, and the suspension is post-treated to obtain a BiOCl photocatalytic material.

2. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The ultrasonic frequency is 20KHz~40KHz.

3. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The microwave power is 160W~480W.

4. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The ultrasonic microwave chemical reaction time is 0.5h to 3h.

5. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The ultrasonic microwave chemical reaction temperature is 80℃~120℃.

6. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The usage ratio of the soluble Bi salt to the first solvent is 0.01 mol:10 mL to 25 mL, the soluble Bi salt is Bi(NO3)3·5H2O, and the first solvent is ethylene glycol, ethanol or methanol.

7. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The usage ratio of the soluble chloride salt to the second solvent is 0.012 mol:10 mL to 25 mL, the soluble chloride salt is NaCl or KCl, and the second solvent is ethylene glycol, ethanol or methanol.

8. The method for preparing the BiOCl photocatalytic material according to claim 1, characterized in that: The volume ratio of the second solution to the first solution is 1:

1.

9. A BiOCl photocatalytic material prepared by the preparation method according to any one of claims 1 to 8.

10. Use of the BiOCl photocatalytic material according to claim 9 in catalytic degradation of organic pollutants.

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