A method for preparing and applying an iron titanate / zinc indium sulfide composite material

Abstract

This invention belongs to the field of photocatalysis technology for composite materials, and provides a method for preparing and applying an iron titanate / indium zinc sulfide composite material. The preparation method involves a two-step hydrothermal in-situ growth process. First, iron titanate is prepared by stirring, hydrothermal reaction, and calcination of iron and titanium sources. Then, iron titanate is mixed with zinc, indium, and sulfur sources, ultrasonically dispersed, and subjected to hydrothermal reaction to obtain the composite material. The raw materials are abundant, the operation is simple, and no complex equipment or processes are required, reducing preparation costs and facilitating large-scale industrial production. The obtained composite material has a good crystal structure, which reduces the recombination probability of photogenerated carriers and significantly improves photocatalytic activity. The iron titanate / indium zinc sulfide composite material exhibits good visible light degradation performance for various dye wastewaters.

Description

Technical Field

[0001] This invention belongs to the field of composite material photocatalysis technology, specifically relating to a method for preparing and applying an iron titanate / indium zinc sulfide composite material. Background Technology

[0002] With the increasing severity of the global energy crisis and environmental pollution, the development of efficient and sustainable environmental governance and energy conversion technologies has become a research hotspot. Photocatalysis, as a highly promising green technology, has attracted widespread attention. Photocatalytic reactions utilize photogenerated carriers (electron-hole pairs) produced by a photocatalyst under illumination to drive a series of chemical reactions, thereby achieving functions such as pollutant degradation, water splitting for hydrogen production, and carbon dioxide reduction.

[0003] Among numerous photocatalysts, composite materials exhibit unique advantages. By combining materials with different properties, key performance characteristics of photocatalysts, such as light absorption, separation efficiency of photogenerated carriers, and stability, can be effectively improved. For example, combining semiconductor materials with good light absorption capabilities with materials possessing high specific surface area and excellent electron transport properties can broaden the spectral response range of photocatalysts, increase the migration rate of photogenerated carriers, and thus enhance photocatalytic activity.

[0004] Composite material photocatalysis has wide applications in environmental governance and energy. In the environmental field, photocatalysis can be used to degrade harmful gases in the air, such as formaldehyde, benzene, and other volatile organic compounds, as well as organic pollutants in water, such as dyes and pesticide residues. Through photocatalytic reactions, these pollutants can be completely decomposed into harmless carbon dioxide and water, achieving environmental purification. In the energy field, photocatalytic water splitting to produce hydrogen provides a feasible way to obtain clean energy. Utilizing solar energy to split water into hydrogen and oxygen, hydrogen, as a highly efficient and clean energy carrier, holds promise for alleviating the current energy crisis. Furthermore, photocatalytic carbon dioxide reduction can convert carbon dioxide into valuable fuels or chemicals, achieving carbon recycling.

[0005] However, composite material photocatalysis still faces many challenges. First, the high recombination rate of photogenerated carriers severely limits further improvements in photocatalytic efficiency. Although combining different materials can promote the separation of photogenerated carriers to some extent, in practical applications, photogenerated electrons and holes are still prone to recombination, resulting in low quantum efficiency of the photocatalytic reaction. Second, the stability of photocatalysts cannot be ignored. During long-term photocatalytic reactions, photocatalysts may undergo aggregation and deactivation, affecting their lifespan and practical application performance. Furthermore, existing composite material preparation methods are often complex and costly, hindering large-scale industrial production.

[0006] To address these issues, developing a highly efficient, stable, and easily prepared composite photocatalyst is of significant practical importance. Zinc indium sulfide (ZnIn2S4), as a ternary sulfide semiconductor material, possesses a suitable bandgap and good visible light absorption, offering a large specific surface area and numerous active sites, making it a highly promising photocatalytic material. Iron titanate (FeTiO3), as a perovskite oxide, exhibits excellent chemical stability and optical properties. Many studies have used ZnIn2S4 or iron titanate as base materials to construct composite materials for application in environmental or energy fields. Truong et al. (10.1016 / j.catcom.2011.12.025) synthesized a FeTiO3 / TiO2 composite material using a simple hydrothermal method. This material possesses unique band structure, effective charge transfer between the two semiconductors, and the low bandgap of FeTiO3, resulting in significant photocatalytic activity for the reduction of CO2 to CH3OH under visible and UV-Vis irradiation. Yuan et al. (10.1016 / j.cclet.2013.06.011) successfully synthesized a novel core-shell composite material TiO2@ZnIn2S4 by a simple and flexible hydrothermal method. This composite material is more efficient than TiO2 and ZnIn2S4 in the photocatalytic degradation of methylene blue.

[0007] However, to date, there have been no reports on the materials, preparation methods, and applications of combining zinc indium sulfide and iron titanate to construct iron titanate / zinc indium sulfide composite materials.

[0008] In view of the above background and current research status, this invention is proposed. Summary of the Invention

[0009] The purpose of this invention is to provide a method for preparing an iron titanate / indium zinc sulfide composite material. This method involves in-situ growth via a two-step hydrothermal process, which is simple and utilizes abundant raw materials. The composite material prepared by this method exhibits a good crystal structure, excellent carrier transport characteristics, and high photocatalytic activity.

[0010] Another objective of this invention is to provide an application of an iron titanate / indium zinc sulfide composite material in the field of removing environmental pollutants.

[0011] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0012] In a first aspect, the present invention provides a method for preparing an iron titanate / zinc indium sulfide composite material, comprising the following steps:

[0013] (1) Preparation of iron titanate: Add iron source to anhydrous ethanol, stir until completely dissolved, then add titanium source dropwise, and add ethylenediamine dropwise under continuous stirring to form a sol. Then carry out hydrothermal reaction, cool, wash with water, wash with alcohol, vacuum dry, and calcine under inert gas protection to obtain iron titanate.

[0014] (2) Preparation of iron titanate / zinc indium sulfide composite material: The iron titanate, zinc source, indium source and sulfur source obtained in step (1) are added to anhydrous ethanol in a certain proportion, hexadecyltrimethylammonium bromide is added, and after ultrasonic dispersion to form a solution, it is transferred to a hydrothermal reactor for reaction. The obtained solid is centrifuged, washed and dried to obtain iron titanate / zinc indium sulfide composite material.

[0015] In this invention, both the hydrothermal reaction and calcination operations are carried out in equipment commonly used in the field. This application does not impose any special limitations, such as the hydrothermal reaction being carried out in a hydrothermal reactor and the calcination being carried out in a tubular furnace.

[0016] In the preparation method of the iron titanate / zinc indium sulfide composite material of the present invention, the iron source in step (1) is one of ferric nitrate, ferric chloride and ferric sulfate.

[0017] In the preparation method of the iron titanate / zinc indium sulfide composite material of the present invention, the titanium source in step (1) is one of tetrabutyl titanate and / or tetraisopropyl titanate.

[0018] In the preparation method of the iron titanate / zinc indium sulfide composite material of the present invention, the zinc source in step (2) is one of zinc nitrate hydrate, zinc acetate dihydrate or zinc chloride.

[0019] In the preparation method of the iron titanate / indium zinc sulfide composite material of the present invention, the indium source in step (2) is one of indium nitrate hydrate, indium trichloride hydrate or indium sulfate.

[0020] In the preparation method of the iron titanate / zinc indium thiosulfate composite material of the present invention, the sulfur source in step (2) is one of thioacetamide, sodium sulfide or thiourea.

[0021] In the preparation method of the iron titanate / zinc indium sulfide composite material of the present invention, the molar ratio of zinc atoms, indium atoms and sulfur atoms in step (2) is 1:2:6.

[0022] In some embodiments, the hydrothermal reaction conditions in step (1) are: temperature of 160~200℃ and reaction time of 8~24 hours.

[0023] In some embodiments, the calcination conditions in step (1) are: temperature of 650~700℃, time of 2~3 hours, and calcination atmosphere of nitrogen.

[0024] In some embodiments, the hydrothermal reaction conditions in step (2) are: temperature of 150~200℃ and reaction time of 8~24 hours.

[0025] Secondly, the present invention provides an application of the iron titanate / indium zinc sulfide composite material prepared by the above preparation method in the field of removing environmental pollutants.

[0026] The environmental pollutants include at least one of Rhodamine B, methylene blue, and methyl orange dye.

[0027] As a preferred embodiment, a method for preparing an iron titanate / zinc indium sulfide composite material includes the following steps:

[0028] (1) Preparation of iron titanate: Add iron source to anhydrous ethanol, stir until completely dissolved, then add titanium source dropwise, and add ethylenediamine dropwise under continuous stirring to form a sol. Then carry out hydrothermal reaction, cool, wash with water, wash with alcohol, vacuum dry, and calcine under inert gas protection to obtain iron titanate.

[0029] (2) Preparation of iron titanate / zinc indium sulfide composite material: The iron titanate, zinc source, indium source and sulfur source obtained in step (1) are added to anhydrous ethanol in a certain proportion, hexadecyltrimethylammonium bromide is added, and after ultrasonic dispersion to form a solution, it is transferred to a hydrothermal reactor for reaction. The obtained solid is centrifuged, washed and dried to obtain iron titanate / zinc indium sulfide composite material.

[0030] In step (1), the iron source is one of ferric nitrate, ferric chloride and ferric sulfate.

[0031] In step (1), the titanium source is one of tetrabutyl titanate and / or tetraisopropyl titanate.

[0032] In step (2), the zinc source is one of zinc nitrate hydrate, zinc acetate dihydrate, or zinc chloride.

[0033] In step (2), the indium source is one of indium nitrate hydrate, indium trichloride hydrate, or indium sulfate.

[0034] In step (2), the sulfur source is one of thioacetamide, sodium sulfide or thiourea.

[0035] In step (2), the molar ratio of zinc atoms, indium atoms and sulfur atoms is 1:2:6.

[0036] In step (1), the hydrothermal reaction conditions are: temperature 200℃ and reaction time 12 hours.

[0037] In step (1), the calcination conditions are: temperature of 700℃, time of 2 hours, and calcination atmosphere of nitrogen.

[0038] In step (2), the hydrothermal reaction conditions are: temperature 180℃ and reaction time 24 hours.

[0039] The beneficial effects of the technical solution provided by this invention are as follows: In terms of preparation method, a two-step hydrothermal in-situ growth method is adopted, which is simple to operate, requires no complex equipment or processes, and has widely available raw materials, reducing preparation costs and laying the foundation for large-scale industrial production. From the perspective of composite material performance, the prepared iron titanate / indium zinc sulfide composite material has a good crystal structure, which facilitates the efficient transport of photogenerated carriers within the material, reduces the probability of carrier recombination, and significantly improves photocatalytic activity, demonstrating superior efficiency in applications such as environmental pollutant removal. In the field of environmental remediation, this composite material can effectively remove dye pollutants such as Rhodamine B, methylene blue, and methyl orange, completely decomposing them into harmless carbon dioxide and water, helping to solve water pollution problems and achieve environmental purification. In summary, the technical solution of this invention demonstrates outstanding advantages in terms of ease of preparation, improved material performance, and environmental remediation applications, and is of great significance for promoting the development and practical application of composite material photocatalysis technology. Attached Figure Description

[0040] Figure 1 The image shown is the XRD pattern of the sample obtained in Example 1 of this invention. Detailed Implementation

[0041] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0042] The present invention will be further illustrated below by way of examples. Unless otherwise specified, the materials in the examples are prepared according to existing methods or purchased directly from the market.

[0043] The reagents and raw materials used in this invention are shown in Table 1 below:

[0044] Table 1. Reagents and raw materials used in this invention

[0045] Reagent Name Molecular formula Specification Manufacturer (Place of Origin) Ferric chloride <![CDATA[FeCl3·6H2O]]> Analytical Pure Shanghai McLean Biochemical Technology Co., Ltd. Ferric nitrate <![CDATA[Fe(NO3)3·9H2O]]> Analytical Pure Shanghai McLean Biochemical Technology Co., Ltd. ethylenediamine <![CDATA[C2H8N2·H2O]]> Analytical Pure Aladdin Chemical Reagent Co., Ltd. Tetrabutyl titanate <![CDATA[C 16 H 36 O4Ti]]> Analytical Pure Sinopharm Chemical Reagent Co., Ltd. Hexadecyltrimethylammonium bromide CTAB Analytical Pure Shanghai McLean Biochemical Technology Co., Ltd. Zinc acetate dihydrate <![CDATA[Zn(CH3COO)2·2H2O]]> Analytical Pure Sinopharm Chemical Reagent Co., Ltd. Indium nitrate hydrate <![CDATA[In(NO)3·xH2O]]> Analytical Pure Shanghai McLean Biochemical Technology Co., Ltd. Thioacetamide <![CDATA[C2H5NS]]> Analytical Pure Sinopharm Chemical Reagent Co., Ltd. Deionized water <![CDATA[H2O]]> <![CDATA[S<5 μs·cm -1 ]]> Hangzhou Wahaha Group Co., Ltd. Example 1

[0046] Accurately weigh 3.56 g of ferric nitrate and dissolve it in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, accurately pipette 3 mL of tetrabutyl titanate (approximately 3 g) and add it dropwise to the above solution. Continue stirring for 30 minutes, then transfer the solution to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Add ethylenediamine dropwise until a sol forms, then add anhydrous ethanol to approximately 70% concentration. React at 200 °C for 12 hours. The resulting precipitate is washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product is calcined in a tube furnace at 700 °C for 2 hours under nitrogen protection to obtain ferric titanate. Accurately weigh 0.5 g of the above-mentioned iron titanate and add it to 50 mL of anhydrous ethanol. Weigh 2 mmol of zinc acetate dihydrate, 4 mmol of indium nitrate hydrate and 12 mmol of thioacetamide into a 100 mL beaker, add 50 mL of anhydrous ethanol, stir to dissolve, then add 0.1 g of hexadecyltrimethylammonium bromide. Continue to sonicate and stir, then transfer to a 100 mL polytetrafluoroethylene-lined hydrothermal reactor. Add anhydrous ethanol to 75% of the total volume. After hydrothermal reaction at 180 °C for 24 hours, the obtained solid is centrifuged, washed with water and alcohol three times each, and vacuum dried at 60 °C for 24 hours to obtain the iron titanate / zinc indium thiosulfate composite material.

[0047] 100 mg of the prepared iron titanate / zinc indium sulfide composite material was placed in a beaker containing 100 mL of a 10 mg / L Rhodamine B solution. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated with a 300 W xenon lamp at a distance of 20 cm from the liquid surface for 60 minutes with stirring. After degradation, the solution was centrifuged and the absorbance at 554 nm was measured by a UV-Vis spectrophotometer. The degradation rate of Rhodamine B was calculated to be 95.6%.

[0048] The iron titanate / zinc indium sulfide composite material prepared in Example 1 of this invention was characterized by XRD using a Bruker D8 Advance X-ray diffractometer (Germany). The results are as follows: Figure 1 As shown. The test conditions were: Cu target Kα line, λ = 0.15406 nm, 2θ = 10°~70°, and scan rate of 10° / min. Figure 1 The product of Example 1 is a ferric titanate / zinc indium sulfide composite material. In the figure, the diffraction peaks at 27.4° and 47.5° correspond to the (102) and (110) crystal planes of zinc indium sulfide (JCPDS 65-2023), respectively. The remaining characteristic peaks belong to the (002), (200), (201), (110), (111), (112), (203), (004), (310), (400), and (113) crystal planes of ferric titanate (JCPDS 73-1631) in the Ccmm space group. All peaks are sharp, indicating that the prepared sample has a good crystal structure and high purity. Example 2

[0049] Accurately weigh 3.56 g of ferric nitrate and dissolve it in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, accurately pipette 3 mL of tetrabutyl titanate (approximately 3 g) and add it dropwise to the above solution. Continue stirring for 30 minutes, then transfer the solution to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Add ethylenediamine dropwise until a sol forms, then add anhydrous ethanol to approximately 70% concentration. React at 200 °C for 12 hours. The resulting precipitate is washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product is calcined in a tube furnace at 700 °C for 2 hours under nitrogen protection to obtain ferric titanate. Accurately weigh 0.5 g of the above-mentioned iron titanate and add it to 50 mL of anhydrous ethanol. Weigh 2 mmol of zinc acetate dihydrate, 4 mmol of indium nitrate hydrate and 12 mmol of thioacetamide into a 100 mL beaker, add 50 mL of anhydrous ethanol, stir to dissolve, then add 0.1 g of hexadecyltrimethylammonium bromide. Continue to sonicate and stir, then transfer to a 100 mL polytetrafluoroethylene-lined hydrothermal reactor. Add anhydrous ethanol to 75% of the total volume. After hydrothermal reaction at 180 °C for 24 hours, the obtained solid is centrifuged, washed with water and alcohol three times each, and vacuum dried at 60 °C for 24 hours to obtain the iron titanate / zinc indium thiosulfate composite material.

[0050] 100 mg of the prepared iron titanate / zinc indium sulfide composite material was placed in a beaker containing 10 mL of a 10 mg / L methylene blue solution. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated with a 300 W xenon lamp at a distance of 20 cm from the liquid surface for 60 minutes with stirring. After degradation, the solution was centrifuged and the absorbance at 664 nm was measured by a UV-Vis spectrophotometer. The degradation rate of methylene blue was calculated to be 92.1%. Example 3

[0051] Accurately weigh 3.56 g of ferric nitrate and dissolve it in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, accurately pipette 3 mL of tetrabutyl titanate (approximately 3 g) and add it dropwise to the above solution. Continue stirring for 30 minutes, then transfer the solution to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Add ethylenediamine dropwise until a sol forms, then add anhydrous ethanol to approximately 70% concentration. React at 200 °C for 12 hours. The resulting precipitate is washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product is calcined in a tube furnace at 700 °C for 2 hours under nitrogen protection to obtain ferric titanate. Accurately weigh 0.5 g of the above-mentioned iron titanate and add it to 50 mL of anhydrous ethanol. Weigh 2 mmol of zinc acetate dihydrate, 4 mmol of indium nitrate hydrate and 12 mmol of thioacetamide into a 100 mL beaker, add 50 mL of anhydrous ethanol, stir to dissolve, then add 0.1 g of hexadecyltrimethylammonium bromide. Continue to sonicate and stir, then transfer to a 100 mL polytetrafluoroethylene-lined hydrothermal reactor. Add anhydrous ethanol to 75% of the total volume. After hydrothermal reaction at 180 °C for 24 hours, the obtained solid is centrifuged, washed with water and alcohol three times each, and vacuum dried at 60 °C for 24 hours to obtain the iron titanate / zinc indium thiosulfate composite material.

[0052] 100 mg of the prepared iron titanate / zinc indium sulfide composite material was placed in a beaker containing 100 mL of methyl orange solution with a concentration of 10 mg / L. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated with a 300 W xenon lamp at a distance of 20 cm from the liquid surface for 60 minutes with stirring. After degradation, the solution was centrifuged and the absorbance at 460 nm was measured by a UV-Vis spectrophotometer. The degradation rate of methyl orange was calculated to be 85.7%. Example 4

[0053] Accurately weigh 3.56 g of ferric nitrate and dissolve it in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, accurately pipette 3 mL of tetrabutyl titanate (approximately 3 g) and add it dropwise to the above solution. Continue stirring for 30 minutes, then transfer the solution to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Add ethylenediamine dropwise until a sol forms, then add anhydrous ethanol to approximately 70% concentration. React at 160 °C for 8 hours. The resulting precipitate is washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product is calcined in a tube furnace under nitrogen protection at 650 °C for 2 hours to obtain ferric titanate. Accurately weigh 0.5 g of the above-mentioned iron titanate and add it to 50 mL of anhydrous ethanol. Weigh 2 mmol of zinc acetate dihydrate, 4 mmol of indium nitrate hydrate and 12 mmol of thioacetamide into a 100 mL beaker, add 50 mL of anhydrous ethanol, stir to dissolve, then add 0.1 g of hexadecyltrimethylammonium bromide. Continue to sonicate and stir, then transfer to a 100 mL polytetrafluoroethylene-lined hydrothermal reactor. Add anhydrous ethanol to 75% of the total volume. After hydrothermal reaction at 150 °C for 8 hours, the obtained solid is centrifuged, washed with water and alcohol 3 times each, and vacuum dried at 60 °C for 24 hours to obtain the iron titanate / zinc indium thiosulfate composite material.

[0054] 100 mg of the prepared iron titanate / zinc indium sulfide composite material was placed in a beaker containing 100 mL of a 10 mg / L Rhodamine B solution. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated with a 300 W xenon lamp at a distance of 20 cm from the liquid surface for 60 minutes with stirring. After degradation, the solution was centrifuged and the absorbance at 554 nm was measured by a UV-Vis spectrophotometer. The degradation rate of Rhodamine B was calculated to be 90.8%. Example 5

[0055] Accurately weigh 3.56 g of ferric nitrate and dissolve it in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, accurately pipette 3 mL of tetrabutyl titanate (approximately 3 g) and add it dropwise to the above solution. Continue stirring for 30 minutes, then transfer the solution to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Add ethylenediamine dropwise until a sol forms, then add anhydrous ethanol to approximately 70% concentration. React at 200 °C for 24 hours. The resulting precipitate is washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product is calcined in a tube furnace at 700 °C for 2 hours under nitrogen protection to obtain ferric titanate. Accurately weigh 0.5 g of the above-mentioned iron titanate and add it to 50 mL of anhydrous ethanol. Weigh 2 mmol of zinc acetate dihydrate, 4 mmol of indium nitrate hydrate and 12 mmol of thioacetamide into a 100 mL beaker, add 50 mL of anhydrous ethanol, stir to dissolve, then add 0.1 g of hexadecyltrimethylammonium bromide. Continue to sonicate and stir, then transfer to a 100 mL polytetrafluoroethylene-lined hydrothermal reactor. Add anhydrous ethanol to 75% of the total volume. After hydrothermal reaction at 200 °C for 24 hours, the obtained solid is centrifuged, washed with water and alcohol three times each, and vacuum dried at 60 °C for 24 hours to obtain the iron titanate / zinc indium thiosulfate composite material.

[0056] 100 mg of the prepared iron titanate / zinc indium sulfide composite material was placed in a beaker containing 100 mL of a 10 mg / L Rhodamine B solution. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated with a 300 W xenon lamp at a distance of 20 cm from the liquid surface for 60 minutes with stirring. After degradation, the solution was centrifuged and the absorbance at 554 nm was measured by a UV-Vis spectrophotometer. The degradation rate of Rhodamine B was calculated to be 97.3%. Comparative Example 1

[0057] 3.56 g of ferric nitrate was accurately weighed and dissolved in 50 mL of anhydrous ethanol to form a reddish-brown solution. While stirring, 3 mL of tetrabutyl titanate (approximately 3 g) was accurately pipetted dropwise into the above solution. After stirring for 30 minutes, the solution was transferred to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Ethylenediamine was added dropwise until a sol was formed. Anhydrous ethanol was added until the solution reached approximately 70%, and the reaction was carried out at 200 °C for 12 hours. The resulting precipitate was washed with water and then with alcohol, and finally dried under vacuum at 60 °C. The product was calcined in a tube furnace at 700 °C for 2 hours under nitrogen protection to obtain the ferric titanate monomer material.

[0058] 100 mg of the prepared iron titanate monomer material was placed in a beaker containing 100 mL of a 10 mg / L Rhodamine B solution. After sonication for 5 minutes and dark adsorption for 30 minutes, the solution was irradiated for 60 minutes with a 300 W xenon lamp at a distance of 20 cm from the liquid surface under stirring. After degradation, the absorbance of the solution at 554 nm was measured by a UV-Vis spectrophotometer after centrifugation. The degradation rate of Rhodamine B was calculated to be 20.2%. Comparative Example 2

[0059] 2 mmol zinc acetate dihydrate, 4 mmol indium nitrate hydrate, and 12 mmol thioacetamide were weighed into a 100 mL beaker, 50 mL anhydrous ethanol was added, and the mixture was stirred and dissolved. Then 0.1 g cetyltrimethylammonium bromide was added, and the mixture was sonicated and stirred. The mixture was then transferred to a 100 mL hydrothermal reactor lined with polytetrafluoroethylene. Anhydrous ethanol was added to 75% of the total volume. After hydrothermal reaction at 180 °C for 24 hours, the resulting solid was centrifuged, washed with water and alcohol three times each, and then vacuum dried at 60 °C for 24 hours to obtain the zinc indium thiosulfate monomer material.

[0060] 100 mg of the prepared zinc indium sulfide monomer material was placed in a beaker containing 100 mL of a 10 mg / L Rhodamine B solution. After sonication for 2 minutes and dark adsorption for 30 minutes, the solution was irradiated for 60 minutes with a 300 W xenon lamp at a distance of 20 cm from the liquid surface under stirring. After degradation, the solution was centrifuged and the absorbance at 554 nm was measured by a UV-Vis spectrophotometer. The degradation rate of Rhodamine B was calculated to be 46.8%.

[0061] As can be seen from Comparative Examples 1 and 2, the prepared iron titanate monomer materials and indium zinc sulfide monomer materials showed a significant decrease in the degradation effect of Rhodamine B under the same conditions compared with the iron titanate / indium zinc sulfide composite materials. This is mainly because neither the iron titanate monomer materials nor the indium zinc sulfide monomer materials formed a spatial electric field that could efficiently separate photogenerated carriers, and photogenerated electrons and holes were easily reactivated.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for preparing an iron titanate / indium zinc sulfide composite material, characterized in that, Includes the following steps: (1) Preparation of iron titanate: Add iron source to anhydrous ethanol, stir until completely dissolved, then add titanium source dropwise, and add ethylenediamine dropwise under continuous stirring to form a sol. Then carry out hydrothermal reaction, cool, wash with water, wash with alcohol, vacuum dry, and calcine under inert gas protection to obtain iron titanate. (2) Preparation of iron titanate / zinc indium sulfide composite material: The iron titanate, zinc source, indium source and sulfur source obtained in step (1) are added to anhydrous ethanol in a certain proportion, hexadecyltrimethylammonium bromide is added, and after ultrasonic dispersion to form a solution, it is transferred to a hydrothermal reactor for reaction. The obtained solid is centrifuged, washed and dried to obtain iron titanate / zinc indium sulfide composite material. In step (1), the hydrothermal reaction conditions are: temperature 160~200℃, reaction time 8~24 hours; in step (1), the calcination conditions are: temperature 650~700℃, time 2~3 hours, calcination atmosphere is nitrogen; in step (2), the hydrothermal reaction conditions are: temperature 150~200℃, reaction time 8~24 hours.

2. The preparation method according to claim 1, characterized in that, The iron source mentioned in step (1) is one of ferric nitrate, ferric chloride and ferric sulfate.

3. The preparation method according to claim 1, characterized in that, The titanium source mentioned in step (1) is one of tetrabutyl titanate and / or tetraisopropyl titanate.

4. The preparation method according to claim 1, characterized in that, The zinc source mentioned in step (2) is one of zinc nitrate hydrate, zinc acetate dihydrate, or zinc chloride.

5. The preparation method according to claim 1, characterized in that, The indium source mentioned in step (2) is one of indium nitrate hydrate, indium trichloride hydrate, or indium sulfate.

6. The preparation method according to claim 1, characterized in that, The sulfur source mentioned in step (2) is one of thioacetamide, sodium sulfide or thiourea.

7. The preparation method according to claim 1, characterized in that, In step (2), the molar ratio of zinc atoms, indium atoms and sulfur atoms is 1:2:

6.

8. The application of an iron titanate / indium zinc sulfide composite material obtained by any one of claims 1 to 7 in the removal of environmental pollutants.

9. The application according to claim 8, characterized in that, The environmental pollutants include at least one of Rhodamine B, methylene blue, and methyl orange dye.

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