Indium zinc sulfide ZnIn4S7 platelet particles in a layered structure, and a preparation method and application thereof

Abstract

The application discloses layered structure indium zinc sulfide ZnIn4S7 flaky particle and a preparation method and application thereof, and belongs to the technical field of photocatalytic material preparation. According to a certain molar ratio of Zn:In:S:alkali, a sulfur source, a zinc source, an indium source and alkali are mixed and uniformly ground, and are put into a closed system at a certain filling ratio, and after being kept at 100-250 DEG C for 1-12 hours, a new layered structure indium zinc sulfide ZnIn4S7 flaky particle is obtained through water washing, suction filtration and drying. In the preparation process of the layered structure indium zinc sulfide ZnIn4S7 flaky particle, no solvent is needed, and the reaction time is short (ZnIn4S7 flaky particles can be obtained only after 1 hour of reaction), and the layered structure indium zinc sulfide ZnIn4S7 flaky particle has the advantages of simple process, short time consumption, low energy consumption, low cost, high yield, no toxic gas emission, no pollution, suitability for mass production and the like. In addition, the new layered structure indium zinc sulfide ZnIn4S7 flaky particle prepared by the application is applied to the field of degradation of organic pollutants and hydrogen production by water photolysis as a visible light photocatalyst.

Description

Technical Field

[0001] This invention belongs to the field of photocatalytic material preparation technology, specifically relating to a layered structure of indium zinc sulfide (ZnIn4S7) sheet-like particles, its preparation method, and its application. Background Technology

[0002] Ternary metal sulfide indium zinc sulfide (ZnIn2S4, Zn 10 In 16 S 34 Indium zinc sulfide (IZ), such as Zn3In2S6, is a class of narrow bandgap semiconductor materials. With a narrow bandgap (2.3–2.4 eV), it can be excited under visible light irradiation, and the photogenerated electrons that transition to the conduction band exhibit strong reducing properties, demonstrating excellent photocatalytic water splitting for hydrogen production and degradation. Therefore, IZ is widely studied as a photocatalyst.

[0003] Currently, indium zinc sulfide (ZnIn2S4, Zn) is being prepared. 10 In 16 S 34 The main method for producing indium zinc sulfide (Zn3In2S6) is hydrothermal. Zinc sources (ZnCl2, Zn(CH3COO)2, ZnSO4, or Na2ZnO2), indium sources (InCl3, Na3InO3, or In(NO3)3), and sulfur sources (thiourea, thioacetamide, or Na2S) are dissolved in water at a specific molar ratio. The mixture is then reacted at 120–200℃ for 12–24 hours. After washing and filtration, indium zinc sulfide (ZnIn2S4, Zn3In2S6) with different structures is obtained. 10 In 16 S 34 The hydrothermal method for preparing indium zinc sulfide (Zn3In2S6) has advantages such as high purity and good crystal development, but it also suffers from low yield, long reaction cycle, large waste volume, and potential environmental pollution. In addition, some researchers have used ZnCl2, InCl3·4H2O, and thiourea in a Zn:In:S molar ratio of 1:2:4 in a ball mill jar, and ball milled them for 2 hours at 600 r / min to obtain indium zinc sulfide (ZnIn2S4) particles. While the ball milling method for preparing ZnIn2S4 particles has the advantage of high yield, it suffers from severe dust pollution, low product purity, and difficulty in water washing and filtration separation, all of which contribute to environmental pollution and hinder green large-scale production. Summary of the Invention

[0004] The purpose of this invention is to provide layered zinc indium sulfide (ZnIn4S7) sheet-like particles, their preparation method, and applications. This method offers advantages such as simple operation, mild reaction conditions, low equipment requirements, high yield, short processing time, no toxic gas emissions, no introduction of other organic solvents, and no pollution, enabling green large-scale production. The layered zinc indium sulfide (ZnIn4S7) sheet-like particles obtained by this method exhibit strong photocatalytic performance.

[0005] To achieve the above objectives, the preparation method of the present invention is as follows: zinc source, indium source, sulfur source, and alkali are mixed and ground evenly according to the molar ratio of Zn:In:S:alkali = 1:4:(7~12):(1~8), and then filled into a sealed container. After being kept at 100~250℃ for 1~12 hours, the mixture is washed with water, filtered, and dried to obtain layered zinc indium sulfide ZnIn4S7 sheet particles.

[0006] The zinc source is a soluble zincate, such as Na2ZnO2, Na2Zn(OH)4, or ZnCl2.

[0007] The indium source is a soluble indium salt, Na3InO or InCl3.

[0008] The sulfur source is a sulfur-containing compound with a melting point below 250°C: L-cysteine, thioacetamide, or thiourea.

[0009] The alkali is LiOH·H2O, NaOH, or KOH.

[0010] The sealed container is a high-pressure reactor.

[0011] The filling ratio is 1% to 80%.

[0012] The layered zinc indium sulfide (ZnIn4S7) sheet particles prepared by the above method have a sheet-like structure with a particle diameter of 3–6 μm and a sheet thickness of 50–100 nm. The XRD diffraction peak has a characteristic peak at 2θ = 11.27°, which corresponds to an interlayer spacing of 0.75 nm.

[0013] Furthermore, the layered indium zinc sulfide (ZnIn4S7) sheet particles can be used as a photocatalyst to degrade organic pollutants and produce hydrogen through photocatalytic water splitting.

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] This invention involves mixing and grinding a zinc source, an indium source, a sulfur source, and an alkali, then uniformly filling the mixture into a sealed system. After holding at 100–250°C for 1–12 hours, the mixture is washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles. This is similar to previously reported ZnIn2S4 and Zn... 10 In16 S 34 Compared with other methods for preparing indium zinc sulfide photocatalysts such as Zn3In2S6, the layered indium zinc sulfide ZnIn4S7 sheet particles prepared in this invention do not require the addition of solvents and have a short reaction time (ZnIn4S7 sheet particles can be obtained in just 1 hour). This method offers advantages such as simple process, short processing time, low energy consumption, low cost, high yield, no toxic gas emissions, no pollution, and suitability for mass production. Furthermore, the novel layered indium zinc sulfide ZnIn4S7 sheet particles prepared in this invention have been applied as visible light photocatalysts in the degradation of organic pollutants and photocatalytic water splitting for hydrogen production. Attached Figure Description

[0016] Figure 1 The XRD pattern of indium zinc sulfide prepared in Example 1 of this invention;

[0017] Figure 2 The XRD pattern of indium zinc sulfide prepared in Example 2 of this invention;

[0018] Figure 3 The XRD pattern of indium zinc sulfide prepared in Example 5 of this invention;

[0019] Figure 4 This is a scanning electron microscope image of indium zinc sulfide prepared in Example 7 of the present invention;

[0020] Figure 5 This is a photocatalytic degradation diagram of indium zinc sulfide prepared in Example 8 of the present invention;

[0021] Figure 6 The image shows the photocatalytic hydrogen production of indium zinc sulfide prepared in Example 9 of this invention; Detailed Implementation

[0022] To enable those skilled in the art to better understand the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0023] The present invention will now be described in further detail with reference to the accompanying drawings:

[0024] Example 1:

[0025] Zinc source Na2ZnO2, indium source Na3InO, sulfur source thioacetamide, and alkali LiOH·H2O were mixed and ground evenly in a molar ratio of Zn:In:S:alkali = 1:4:7:1 and then placed into a high-pressure reactor at a filling ratio of 1%. After being kept at 100°C for 1 hour, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0026] See Figure 1 The image shown is the XRD pattern of indium zinc sulfide particles prepared in Example 1 of this invention. Figure 1 It can be seen that the indium zinc sulfide particles prepared by this invention are pure in phase, free of impurities, and have good crystallinity.

[0027] Example 2:

[0028] Zinc source ZnCl2, indium source InCl3, sulfur source thiourea, and alkali NaOH were mixed and ground evenly in a molar ratio of Zn:In:S:alkali = 1:4:7:8. The mixture was then placed into a high-pressure reactor at a filling ratio of 80%. After being kept at 250°C for 12 hours, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0029] See Figure 2 The image shown is the XRD pattern of indium zinc sulfide particles prepared in Example 2 of this invention. Figure 2 It can be seen that the indium zinc sulfide particles prepared by this invention are pure in phase, free of impurities, and have good crystallinity.

[0030] Example 3:

[0031] Zinc source Na2Zn(OH)4, indium source InCl3, sulfur source L-cysteine, and base KOH were mixed and ground evenly in a molar ratio of Zn:In:S:base = 1:4:12:1. The mixture was then placed into a high-pressure reactor at a filling ratio of 1% and kept at 180°C for 4 hours. After washing with water, filtration, and drying, layered zinc indium sulfide (ZnIn4S7) flake particles were obtained.

[0032] Example 4:

[0033] Zinc source ZnCl2, indium source Na3InO, sulfur source thiourea, and alkali LiOH·H2O were mixed and ground evenly in a molar ratio of Zn:In:S:alkali = 1:4:12:8 and then placed into a high-pressure reactor at a filling ratio of 15%. After being kept at 220°C for 6 hours, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0034] Example 5:

[0035] Zinc source Na2ZnO2, indium source Na3InO, sulfur source thioacetamide, and alkali NaOH were mixed and ground evenly in a molar ratio of Zn:In:S:alkali = 1:4:10:8. The mixture was then placed into a high-pressure reactor at a filling ratio of 30%. After being kept at 160°C for 6 hours, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0036] See Figure 3 The image shown is the XRD pattern of indium zinc sulfide particles prepared in Example 5 of this invention. Figure 3 It can be seen that the indium zinc sulfide particles prepared by this invention are pure in phase, free of impurities, and have good crystallinity.

[0037] Example 6:

[0038] Zinc source ZnCl2, indium source InCl3, sulfur source thiourea, and alkali KOH were mixed and ground evenly in a molar ratio of Zn:In:S:alkali = 1:4:10:1. The mixture was then placed into a high-pressure reactor at a filling ratio of 5%. After being kept at 200°C for 8 hours, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0039] Example 7:

[0040] Zinc source Na2Zn(OH)4, indium source InCl3, sulfur source L-cysteine, and base LiOH·H2O were mixed and ground evenly in a molar ratio of Zn:In:S:base = 1:4:8:1 and then placed into a high-pressure reactor at a filling ratio of 80%. After being kept at 250°C for 6 hours, the mixture was washed with water, filtered, and dried to obtain layered zinc indium sulfide (ZnIn4S7) flake particles.

[0041] See Figure 4 This is a scanning electron microscope (SEM) image of indium zinc sulfide particles prepared in Example 7 of this invention. Figure 4 It can be seen that the indium zinc sulfide particles prepared by this invention have uniform particle size and regular shape.

[0042] Example 8:

[0043] Zinc source Na2Zn(OH)4, indium source InCl3, sulfur source L-cysteine, and base NaOH were mixed and ground evenly in a molar ratio of Zn:In:S:base = 1:4:12:8. The mixture was then placed into a high-pressure reactor at a filling ratio of 40% and kept at 220°C for 10 hours. After washing with water, filtration, and drying, layered zinc indium sulfide (ZnIn4S7) flake particles were obtained.

[0044] See Figure 5 This is a photocatalytic degradation diagram of indium zinc sulfide particles prepared in Example 8 of this invention. Figure 5It can be seen that the indium zinc sulfide particles prepared by this invention have excellent photocatalytic degradation performance.

[0045] Example 9:

[0046] Zinc source Na2Zn(OH)4, indium source InCl3, sulfur source L-cysteine, and base KOH were mixed and ground evenly in a molar ratio of Zn:In:S:base = 1:4:9:1. The mixture was then placed into a high-pressure reactor at a filling ratio of 30% and kept at 150°C for 12 hours. After washing with water, filtration, and drying, layered zinc indium sulfide (ZnIn4S7) flake particles were obtained.

[0047] See Figure 6 This is a photocatalytic hydrogen production diagram of indium zinc sulfide particles prepared in Example 9 of this invention. Figure 6 It can be seen that the indium zinc sulfide particles prepared by this invention have excellent photocatalytic hydrogen production performance.

[0048] Example 10:

[0049] Zinc source Na2Zn(OH)4, indium source InCl3, sulfur source L-cysteine, and base KOH were mixed and ground evenly in a molar ratio of Zn:In:S:base = 1:4:9:4. The mixture was then placed into a high-pressure reactor at a filling ratio of 30% and kept at 200°C for 12 hours. After washing with water, filtration, and drying, layered zinc indium sulfide (ZnIn4S7) flake particles were obtained.

[0050] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. Process for the preparation of layered indium zinc sulfide ZnIn4S7 platelet particles, characterized in that: A zinc source, an indium source, a sulfur source and a base are mixed in a molar ratio of Zn:In:(7-12):(1-8), ground uniformly and filled into a sealed container, and then kept at 100-250 DEG C for 1-12 hours, and then washed with water, filtered and dried to obtain layered structure indium zinc sulfide ZnIn4S7 flaky particles; The zinc source is soluble zincate Na2ZnO2, Na2Zn(OH)4 or ZnCl2; The indium source is soluble indate Na3InO or InCl3; The sulfur source is a sulfur-containing compound with a melting point below 250 DEG C, such as L-cysteine, thioacetamide or thiourea; The base is LiOH·H2O, NaOH or KOH.

2. The method for preparing layered structure of indium zinc sulfide ZnIn4S7 platelet particles according to claim 1, characterized in that: The sealed container is a high-pressure reaction kettle.

3. The method for preparing layered structure of indium zinc sulfide ZnIn4S7 platelet particles according to claim 1, characterized in that: The filling ratio is 1%-80%.

4. Layered structure of indium zinc sulfide ZnIn4S7 platelet particles prepared by the method according to any one of claims 1 to 3, characterized in that: The indium zinc sulfide particles have a sheet structure, a particle diameter of 3-6 μm, a sheet thickness of 50-100 nm, and an XRD diffraction peak at 2 = 11.27°, and an interlayer spacing = 0.75 nm.

5. Layered structure indium zinc sulfide ZnIn4S7 flaky particles according to claim 4 as photocatalysts.

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