A Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst and its preparation method

Abstract

The present invention discloses a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst and a preparation method thereof, belonging to the technical field of new materials. The method comprises the following steps: S0: Synthesize Bi2MoO6 hierarchical porous microspheres; S1: Completely dissolve zinc acetate dihydrate and indium nitrate hydrate in ethylene glycol to obtain a type I solution; S2: Add the Bi2MoO6 microspheres into the type I solution and completely disperse to form a type II suspension; S3: Dissolve thioacetamide with a quantitative molar mass ratio in the type II suspension to obtain a turbid solution; S4: Perform a hydrothermal reaction on the turbid solution, and dry the product obtained from the hydrothermal reaction after centrifugation and washing to obtain the Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst. The synthesis method has mild reaction conditions and is simple and easy to operate. Compared with single Bi2MoO6 and ZnIn2S4, the synthesized composite photocatalyst has significantly enhanced CO2 reduction performance.

Description

Technical Field

[0001] The present invention relates to a method for preparing microcrystals, specifically a Bi2MoO6@ZnIn2S4 hierarchical S-type heterostructure photocatalyst and a preparation method thereof, belonging to the technical field of new materials. Background Art

[0002] The problems of energy shortage and global warming caused by the overconsumption of fossil fuels and the excessive emission of CO2 have attracted increasing attention. Using solar energy to reduce CO2 to hydrocarbon fuels (such as CO and CH4) through photocatalysts has become a promising strategy to solve these two problems simultaneously. Nevertheless, due to the high dissociation energy of C=O (~750 kJ·mol -1 )), the conversion efficiency of CO2 is quite low, and developing high-performance photocatalysts is the key to improving the CO2 conversion rate. A large number of photocatalysts (such as TiO2, ZnO, CdS, CdSe, CsPbBr3, ZnIn2S4) are increasingly used for photocatalytic CO2 reduction.

[0003] Ternary metal sulfide ZnIn2S4, as a representative photocatalyst, has attracted great attention due to its narrow bandgap (2.34 - 2.48 eV), relatively negative conduction band potential, layered structure, non-toxicity, and good chemical stability. However, single ZnIn2S4 has low photocatalytic activity for CO2 reduction due to insufficient visible light response ability, severe recombination of photo-generated carriers, and fewer active sites that are not conducive to the adsorption and activation of CO2. Constructing heterostructures and hierarchical structures are two effective strategies to overcome the above disadvantages of single ZnIn2S4. In recent years, a new type of S-scheme heterostructure composed of a reduced photocatalyst and an oxidized photocatalyst not only accelerates the separation of photo-generated electrons and holes but also maintains the original redox ability. Currently, many S-scheme heterostructure photocatalysts (TiO2 / CsPbBr3, AgBr / BiOBr, In4SnS8 / Cs3Bi2Br9, ZnMn2O4 / ZnO, etc.) have been reported and have good photocatalytic activity for CO2 reduction, attracting great attention. At the same time, hierarchical micro / nanostructures (such as sea urchin-like, flower-like, dendritic, and nanoplate-assembled porous microsphere structures) have many advantages: (1) A high specific surface area can provide abundant active sites, which is conducive to the adsorption and activation of catalytic reaction molecules; (2) The unique structure can serve as a scaffold to anchor useful materials and avoid their aggregation and condensation; (3) Multiple reflections and scattering of light in the interconnected porous network can be utilized to improve the light absorption ability, thereby providing more photo-generated charges and effectively improving the catalytic activity. Therefore, by anchoring ZnIn2S4 onto a suitable hierarchical oxidized photocatalyst and reasonably constructing a hierarchical S-scheme heterostructure based on ZnIn2S4, the photocatalytic performance of CO2 reduction can be significantly improved.

[0004] Bi2MoO6 has advantages such as a relatively narrow bandgap (<3 eV, can absorb visible light) and a relatively positive valence band potential, and has been widely studied in many fields such as photocatalytic oxygen production, nitric oxide removal, and organic pollutant degradation. In addition, Bi2MoO6 consists of alternating [Bi2O2] 2+ plates and [MoO4] 2-It consists of plates and has a unique layer structure, making it easy to synthesize hierarchical porous microspheres assembled from nanosheets. More importantly, its energy band structure can be well matched with that of ZnIn2S4. Therefore, Bi2MoO6 is an ideal candidate for coupling with ZnIn2S4 to prepare hierarchical S-scheme heterostructures. Inspired by the above analysis, an unprecedented hierarchical S-scheme heterostructure photocatalyst was successfully created by anchoring ZnIn2S4 nanosheets on the hierarchical porous Bi2MoO6 microspheres assembled from nanosheets. Through in-situ X-ray photoelectron spectroscopy (XPS), the S-scheme transfer mechanism of photo-generated carriers in the Bi2MoO6@ZnIn2S4 heterostructure was demonstrated. In addition, its unique hierarchical heterostructure not only improves the visible light response ability but also has a higher specific surface area, providing sufficient active sites for the adsorption and activation of CO2. Therefore, the optimal photocatalyst (Bi2MoO6@ZnIn2S4-0.4) can efficiently and selectively photoreduce CO2 to CO without any sacrificial agent. Summary of the Invention

[0005] An object of the present invention is to solve at least one of the technical problems existing in the prior art, and to provide a preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst.

[0006] The technical solution of the present invention is as follows:

[0007] A preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst, comprising the following steps:

[0008] S0: Synthesize hierarchical porous Bi2MoO6 microspheres.

[0009] S1: Completely dissolve zinc acetate dihydrate and indium nitrate hydrate in ethylene glycol to obtain a type I solution.

[0010] S2: Add the hierarchical porous Bi2MoO6 microspheres into the type I solution and disperse them completely to form a type II suspension.

[0011] S3: Dissolve a quantitative molar mass ratio of thioacetamide in the type II suspension to obtain a turbid solution.

[0012] S4: Perform a hydrothermal reaction on the turbid solution, and dry the product obtained from the hydrothermal reaction after centrifugation and washing; obtain a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst.

[0013] As a preferred embodiment of the present invention, in step S0, the synthesis method of the hierarchical porous Bi2MoO6 microspheres is as follows:

[0014] S01: Add bismuth nitrate pentahydrate and dodecyl trimethyl ammonium bromide into ethylene glycol. Wait until they are completely dissolved to obtain Solution A.

[0015] S02: Add sodium molybdate dihydrate into ethylene glycol. Wait until it is completely dissolved to obtain Solution B.

[0016] S03: Drop Solution B into Solution A drop by drop for hydrothermal reaction to obtain a milky white precipitate. Centrifuge the precipitate at high speed, wash it with deionized water, and finally dry it in a freeze dryer to prepare the product.

[0017] As a preferred embodiment of the present invention, in steps S01 - 02, the molar ratio of bismuth nitrate pentahydrate to sodium molybdate dihydrate is 1.8 - 2.2:1.

[0018] As a preferred embodiment of the present invention, in step S03, the temperature of the hydrothermal reaction is 80 - 200 °C, and the reaction time is 2 - 48 h.

[0019] As a preferred embodiment of the present invention, in step S03, the dropping speed is 0.5 - 2 drops per second.

[0020] As a preferred embodiment of the present invention, the molar ratio of zinc acetate dihydrate, indium nitrate hydrate, and thioacetamide is 1:2:4 - 8.

[0021] As a preferred embodiment of the present invention, in step S4, the temperature of the hydrothermal reaction is 80 - 200 °C, and the reaction time is 1 - 20 h.

[0022] As a preferred embodiment of the present invention, in step S4, freeze drying is used for drying.

[0023] The present invention also discloses a Bi2MoO6@ZnIn2S4 hierarchical S - type heterostructure photocatalyst prepared by the above - mentioned preparation method.

[0024] The beneficial effects of the present invention are as follows: The synthesis method has mild reaction conditions and is simple and easy to operate. This Bi2MoO6@ZnIn2S4 hierarchical S - type heterostructure photocatalyst can not only improve the visible - light response ability, but also significantly promote the spatial separation and transfer of photo - generated electrons and holes and maintain their original redox ability. In addition, it has a higher specific surface area, providing sufficient active sites, which is beneficial to the adsorption and activation of CO2. Therefore, compared with Bi2MoO6 hierarchical microspheres and ZnIn2S4 nanosheets, the above three advantages synergistically significantly enhance their photocatalytic CO2 reduction performance. Description of the Drawings

[0025] Figure 1XRD patterns and FTIR spectra of the products of the examples of the present invention (Bi2MoO6@ZnIn2S4-0.3, Bi2MoO6@ZnIn2S4-0.4, Bi2MoO6@ZnIn2S4-0.5, abbreviated as BMO@ZIS-0.3, BMO@ZIS-0.4, BMO@ZIS-0.5 respectively) and the comparative examples (Bi2MoO6 hierarchical microspheres and ZnIn2S4 nanosheets, abbreviated as BMO-PMs, ZIS-NFs).

[0026] Figure 2 (a) and (b) are scanning electron microscope (SEM) images of the comparative example (BMO-PMs) of the present invention, Figure 2 (c) is a transmission electron microscope (TEM) image of the comparative example (BMO-PMs) of the present invention, Figure 2 (d) is a high-resolution transmission electron microscope (HRTEM) image of the comparative example (BMO-PMs) of the present invention. Figure 2 (e) and (f) are SEM images of the example (BMO@ZIS-0.4) of the present invention, Figure 2 (g) is a TEM image of the example (BMO@ZIS-0.4) of the present invention, Figure 2 (h) is a HRTEM image of the example (BMO@ZIS-0.4) of the present invention, Figure 2 (i) is an elemental distribution map of the example (BMO@ZIS-0.4) of the present invention.

[0027] Figure 3 XPS spectra of the examples and comparative examples (BMO-PMs and ZIS-NFs) of the present invention under light and dark conditions.

[0028] Figure 4 (a) N2 adsorption-desorption isotherms and (b) pore size distribution curves of the examples and comparative examples (BMO-PMs and ZIS-NFs) of the present invention, Figure 4 (c) is the UV-visible absorption spectrum of the examples and comparative examples (BMO-PMs and ZIS-NFs) of the present invention, Figure 4 (d) is (αhν) of the comparative examples (BMO-PMs and ZIS-NFs) of the present invention 2 Function curve diagram with respect to hν.

[0029] Figure 5 (a) and (b) are photocatalytic CO2 reduction performance test diagrams of the examples and comparative examples (BMO-PMs and ZIS-NFs) of the present invention, Figure 5 (c) is the photocatalytic CO2 reduction cycle test diagram of the example (BMO@ZIS-0.4) of the present invention, Figure 5(d) is the photocatalytic CO2 reduction performance test chart of the embodiment of the present invention (BMO@ZIS-0.4) under different conditions.

[0030] Figure 6 (a) is the CO2 adsorption isotherm test chart of the embodiment of the present invention and comparative examples (BMO-PMs and ZIS-NFs). Figure 6 (b) is the CO temperature-programmed desorption curve of the embodiment of the present invention and comparative example (ZIS-NFs). Figure 6 (c) is the in-situ FTIR of the photocatalytic CO2 reduction of the embodiment of the present invention (BMO@ZIS-0.4). Detailed implementation manners

[0031] The present invention will be further described below in conjunction with embodiments and comparative examples.

[0032] Experimental preparation: Synthesis of Bi2MoO6 hierarchical porous microspheres: (1) Add 2 mmol of bismuth nitrate pentahydrate and 0.3 g of dodecyltrimethylammonium bromide to 15 mL of ethylene glycol, and then magnetically stir for 0.5 h until completely dissolved to obtain solution A; (2) Add 1 mmol of sodium molybdate dihydrate to 15 mL of ethylene glycol, and ultrasonicate for 10 min until completely dissolved to obtain solution B; (3) Dropwise add solution B into solution A, magnetically stir for 0.5 h, and then transfer the mixture to a 100 mL hydrothermal autoclave; (4) Hydrothermally react at 180 °C for 12 h to obtain a milky white precipitate, centrifuge at a high speed of 10000 rpm for 5 min, wash 3 times with deionized water, and finally dry in a freeze dryer for 12 hours to obtain Bi2MoO6 hierarchical porous microspheres.

[0033] Synthesis of Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst and ZnIn2S4 nanosheets: (1) First, a certain amount of zinc acetate dihydrate and indium nitrate hydrate were completely dissolved in 30 mL of ethylene glycol under stirring at a molar ratio of 1:2 to obtain Solution I; (2) 0.3 g of the prepared Bi2MoO6 was added to the above solution and ultrasonically stirred until completely dispersed to form Suspension II; (3) A quantitative mass ratio of thioacetamide (zinc acetate dihydrate: indium nitrate hydrate: thioacetamide = 1:2:4) was dissolved in Suspension II, and magnetically stirred for 0.5 h, and then this suspension was transferred to a 50 mL hydrothermal reactor; (4) After hydrothermal reaction at 120 °C for 2 h, the product was centrifuged, washed and dried to obtain the Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst. The calculated mass ratio (Q) of ZnIn2S4 to Bi2MoO6 was 0.3, 0.4, and 0.5, respectively, and the corresponding samples were named BMO@ZIS-0.3, BMO@ZIS-0.4, and BMO@ZIS-0.5, which showed good performance in photocatalysis; (5) The synthesis of ZnIn2S4 nanosheets was the same as the above synthesis method except that Bi2MoO6 was not added.

[0034] Example

[0035] Synthesis of BMO@ZIS-0.3, BMO@ZIS-0.4, and BMO@ZIS-0.5:

[0036] (1) A certain amount of zinc acetate dihydrate and indium nitrate hydrate were completely dissolved in 30 mL of ethylene glycol under stirring at a molar ratio of 1:2 to obtain Solution I.

[0037] (2) 0.3 g of the prepared Bi2MoO6 was added to the above solution and ultrasonically stirred until completely dispersed to form Suspension II.

[0038] (3) A quantitative molar mass ratio of thioacetamide (zinc acetate dihydrate: indium nitrate hydrate: thioacetamide = 1:2:4) was dissolved in Suspension II, and then magnetically stirred for 0.5 h, and then this suspension was transferred to a 50 mL hydrothermal reactor.

[0039] (4) After hydrothermal reaction at 120 °C for 2 h, the product was centrifuged, washed and dried to obtain the Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst.

[0040] Comparative Example

[0041] To prove that the BMO@ZIS-0.4 hierarchical structure can enhance the visible light response ability, provide abundant active sites, and the S-type heterojunction can accelerate the migration and separation of photo-generated carriers, we obtained single Bi2MoO6 and ZnIn2S4 through different routes.

[0042] (a) The synthesis of Bi2MoO6 hierarchical porous microspheres is as follows:

[0043] (1) Add 2 mmol of bismuth nitrate pentahydrate and 0.3 g of dodecyltrimethylammonium bromide to 15 mL of ethylene glycol, and then magnetically stir for 0.5 h until completely dissolved to obtain solution A.

[0044] (2) Add 1 mmol of sodium molybdate dihydrate to 15 mL of ethylene glycol, and ultrasonicate for 10 min until completely dissolved to obtain solution B.

[0045] (3) Drop solution B into solution A drop by drop, magnetically stir for 0.5 h, and then transfer the mixture to a 100 mL hydrothermal reactor.

[0046] (4) After hydrothermal reaction at 180 °C for 12 h, a milky white precipitate is obtained, centrifuged at 10000 rpm for 5 min, washed 3 times with deionized water, and finally dried in a freeze dryer for 12 hours to obtain Bi2MoO6 hierarchical porous microspheres.

[0047] (b) The synthesis of ZnIn2S4 nanosheets is as follows:

[0048] (1) Completely dissolve 1 mmol of zinc acetate dihydrate and 2 mmol of indium nitrate hydrate in 30 mL of ethylene glycol under stirring to form solution I.

[0049] (2) Add 4 mmol of thioacetamide to the above solution, and ultrasonically stir until completely dissolved to form solution II.

[0050] (3) After hydrothermal reaction at 120 °C for 2 h, the product is centrifuged, washed, and dried to obtain ZnIn2S4 nanosheets.

[0051] The products were analyzed by XRD, SEM, TEM, UV-visible absorption spectroscopy, XPS, N2 adsorption-desorption isotherms, CO2 adsorption isotherms, CO temperature-programmed desorption curves, and in-situ FTIR of CO2 photoreduction.

[0052] Figure 1 a is the XRD pattern of the products of the examples and comparative examples. From Figure 1It can be seen from (a) that no impurity phases are generated in the examples and comparative examples (Bi2MoO6 and ZnIn2S4). JCPDS No. 21-0102 is the standard XRD pattern of Bi2MoO6, and JCPDS No. 65-2023 is the standard XRD pattern of ZnIn2S4. Although the characteristic peaks of ZnIn2S4 cannot be observed in BMO@ZIS-0.3, BMO@ZIS-0.4, and BMO@ZIS-0.5, the reason is that the content of ZnIn2S4 is less and its dispersion is better. Figure 1 (b) is the FTIR diagram of the examples and comparative examples. It should be noted that the typical peaks of ZnIn2S4 (880 cm -1 ) and Bi2MoO6 (526 and 750 cm -1 ) can be clearly detected in the Bi2MoO6@ZnIn2S4 composite, proving that the Bi2MoO6@ZnIn2S4 composite is in a state where ZnIn2S4 and Bi2MoO6 coexist.

[0053] Figure 2 (a) and (b) are the SEM diagrams of the products of the comparative example (Bi2MoO6). Figure 2 (c) and (d) are the TEM diagrams of the products of the comparative example (Bi2MoO6), indicating that Bi2MoO6 is a microsphere assembled by nanosheets. Figure 2 (e) and (f) are the SEM diagrams of the products of the example (BMO@ZIS-0.4). Figure 2 (g) and (h) are the TEM diagrams of the products of the example (BMO@ZIS-0.4), indicating that ZnIn2S4 nanosheets are anchored on the hierarchical microspheres of nanosheet-assembled Bi2MoO6. Figure 2 (i) is the EDX elemental distribution diagram of the product of the example (BMO@ZIS-0.4), indicating that the example (BMO@ZIS-0.4) is composed of six elements: Bi, Mo, O, Zn, In, and S.

[0054] Figure 3 are the in-situ XPS diagrams of the products of the examples and comparative examples (Bi2MoO6 and ZnIn2S4). It can be seen from the figure that the electron flow direction in the example is from ZnIn2S4 to Bi2MoO6 in the dark and from Bi2MoO6 to ZnIn2S4 under light illumination, proving the S-type transfer mechanism of photogenerated carriers in the example.

[0055] Figure 4(a) and (b) are the (a) N2 adsorption - desorption isotherms and (b) pore size distribution curves of the examples and comparative examples (Bi2MoO6 and ZnIn2S4), indicating that the specific surface area of the examples is significantly higher than that of single Bi2MoO6. Therefore, the heterostructure with a large specific surface area can provide abundant surface active sites, which is beneficial to the adsorption and activation of CO2, thus promoting photocatalytic CO2 reduction. Figure 4 (c) and (d) are the UV - Vis diffuse reflectance spectra of the examples and comparative examples and the function curve of the comparative examples (Bi2MoO6 and ZnIn2S4) (αhν) 2 with respect to hν, indicating the significantly enhanced visible - light response ability of the examples. The band - gap widths of the comparative examples Bi2MoO6 and ZnIn2S4 are 2.94 and 2.61 eV, respectively.

[0056] Figure 5 (a) and (b) are the photocatalytic CO2 reduction performance test diagrams of the examples and comparative examples (Bi2MoO6 and ZnIn2S4). The example BMO@ZIS - 0.4 has the optimal photocatalytic CO2 reduction performance for CO production (the CO production rate and selectivity are 23.11 μmol g -1 h -1 and 93.1%), which is significantly higher than that of the comparative examples (Bi2MoO6 and ZnIn2S4). Figure 5 (c) is the photocatalytic CO2 reduction cycle test diagram of the example BMO@ZIS - 0.4, indicating that the example has excellent cycle stability. Figure 5 (d) is the photocatalytic CO2 reduction performance test diagram of the example BMO@ZIS - 0.4 under different conditions, illustrating that the CO2 photoreduction reaction in the example is photo - driven in the presence of the photocatalyst, and the carbon source of the product only comes from the injected CO2.

[0057] Figure 6 (a) is the CO2 adsorption isotherm test diagram of the examples and comparative examples (Bi2MoO6 and ZnIn2S4), indicating that compared with the comparative example (Bi2MoO6), the CO2 adsorption capacity of the example BMO@ZIS - 0.4 is significantly enhanced (3.82 cm 3 / g), which is significantly enhanced and beneficial to CO2 reduction. Figure 6 (b) is the CO temperature - programmed desorption curve of the examples and comparative examples (ZnIn2S4) of the present invention, illustrating that the example BMO@ZIS - 0.4 is beneficial to CO desorption, thus highly selectively reducing CO2 to CO. Figure 6 (c) is the in - situ Fourier transform infrared curve of the CO2 photoreduction of the examples of the present invention. As the irradiation time increases, the peak intensity representing the intermediate formed during the photocatalytic process gradually increases. The examples show peaks at 1550 and 1567 cm-1 The two peaks that appear at [location] belong to the COOH* intermediate, indicating that CO2 is reduced to CO and CH4 with COOH* as the intermediate.

[0058] Application Example 1

[0059] Five products obtained from the examples and comparative examples: Bi2MoO6, BMO@ZIS-0.3, BMO@ZIS-0.4, BMO@ZIS-0.5, ZnIn2S4. Specifically, 50 mg of the photocatalyst was placed on the reactor with an area of 4.2 cm 2 . A 300W xenon lamp was used as the light source for the photocatalytic reaction. Before irradiation, the reactor was evacuated using a vacuum pump, and then high-purity CO2 gas was introduced into the reaction device to reach ambient pressure. 0.4 mL of deionized water was injected into the reaction flask. The prepared photocatalyst was equilibrated in a CO2 atmosphere for several hours. The temperature of the reaction system was maintained at 25 °C through circulating cooling water. During irradiation, 0.5 mL of gas was withdrawn from the reaction flask every hour and analyzed subsequently using a gas chromatograph (GC9790 IIA, Zhejiang Fujian Analytical Instrument Co., Ltd., China), which was equipped with FID and TCD detectors.

[0060] On the premise of no conflict, those skilled in the art can freely combine and superimpose the above additional technical features.

[0061] The above-described embodiments only represent the preferred embodiments of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, other corresponding changes and deformations can also be made according to the technical solutions and concepts described above, and all such changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

1. A preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst, characterized in that It includes the following steps: S0: Synthesize Bi2MoO6 hierarchical porous microspheres; S1: Completely dissolve zinc acetate dihydrate and indium nitrate hydrate in ethylene glycol to obtain Class I solution; S2: Add Bi2MoO6 hierarchical porous microspheres into the Class I solution and completely disperse to form Class II suspension; S3: Dissolve thioacetamide with a quantitative molar mass ratio in the Class II suspension to obtain a turbid solution; S4: Perform hydrothermal reaction on the turbid solution, and subject the product obtained from the hydrothermal reaction to centrifugation, washing, and then freeze-drying to obtain a Bi2MoO6@ZnIn2S4 hierarchical S-type heterostructure photocatalyst; In step S0, the synthesis method of the Bi2MoO6 hierarchical porous microspheres is as follows: S01: Add bismuth nitrate pentahydrate and dodecyl trimethyl ammonium bromide into ethylene glycol, and wait for them to completely dissolve to obtain Solution A; S02: Add sodium molybdate dihydrate into ethylene glycol, and wait for it to completely dissolve to obtain Solution B; S03: Dropwise add Solution B into Solution A, perform hydrothermal reaction to obtain a milky white precipitate, perform high-speed centrifugation separation on the precipitate, wash it with deionized water, and finally dry it in a freeze dryer.

2. The preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst according to claim 1, characterized in that: In steps S01 - 02, the molar ratio of bismuth nitrate pentahydrate to sodium molybdate dihydrate is 1.8 - 2.2:

1.

3. The preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst according to claim 1, characterized in that: In step S03, the temperature of the hydrothermal reaction is 80 - 200 °C, and the reaction time is 2 - 48 h.

4. The preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst according to claim 1, characterized in that: In step S03, the dropping rate is 0.5 - 2 drops / second.

5. The preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst according to claim 1, characterized in that: The molar ratio of the zinc acetate dihydrate, indium nitrate hydrate, and thioacetamide is 1:2:4 - 8.

6. The preparation method of a Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst according to claim 1, characterized in that: In step S4, the temperature of the hydrothermal reaction is 80 - 200 °C, and the reaction time is 1 - 20 h.

7. A Bi2MoO6@ZnIn2S4 hierarchical S-scheme heterostructure photocatalyst, characterized in that: It is prepared by using the preparation method according to any one of claims 1 - 6.

Images