A method for preparing nano-zinc sulfide powder and its product

Abstract

This application provides a method for preparing nano-zinc sulfide powder and its product, comprising: loading sulfur powder and zinc powder into a first crucible and a second crucible respectively; placing the first crucible and the second crucible into different furnace bodies of a chemical vapor deposition (CVD) furnace; placing a ceramic deposition chamber into the deposition zone furnace body of the CVD furnace; evacuating the CVD furnace to a vacuum level less than or equal to 400 Pa; at room temperature, heating the furnace body containing the first crucible to 300-350 °C at a rate of 5-10 °C / min, heating the furnace body containing the second crucible to 550-650 °C at a rate of 20-30 °C / min, and heating the deposition zone furnace body to 580-680 °C at a rate of 25-35 °C / min; after each furnace body has been heated to the predetermined temperature and held for 8-10 hours, introducing sulfur-carrying gas into the first crucible and zinc-carrying gas into the second crucible; after the reaction is completed, directly turning off the power supply to each furnace body, cooling down, and then opening the furnace to collect the nano-zinc sulfide powder. The obtained nano zinc sulfide powder has high purity, white appearance, and uniform size.

Description

Technical Field

[0001] This application relates to the field of nanomaterials, and in particular to a method for preparing nano-zinc sulfide powder and its product. Background Technology

[0002] Zinc sulfide is a widely used wide-bandgap semiconductor material, which has been extensively applied in electroluminescent devices, optoelectronic devices, photocatalysis, and other fields. Meanwhile, due to its wear resistance, high strength, high temperature resistance, strong hiding power (higher than zinc oxide), and non-toxicity, zinc sulfide powder is also widely used in injection molding, coatings, automotive paints, flame retardants, and other industries. Currently, research on the preparation technology of zinc sulfide nanomaterials has become a hot topic.

[0003] Although there has been a great deal of research on the preparation of nano zinc sulfide powder, various preparation techniques also have their shortcomings. Currently, there is a need for an industrial preparation method for nano zinc sulfide powder with high purity and uniform size. Summary of the Invention

[0004] The purpose of this application is to provide a method for preparing nano-zinc sulfide powder and the resulting product. The specific technical solution is as follows:

[0005] The first aspect of this application provides a method for preparing nano-zinc sulfide powder, which includes the following steps:

[0006] (1) Sulfur powder and zinc powder are loaded into the first crucible and the second crucible respectively. The first crucible and the second crucible are placed in different furnace bodies of the chemical vapor deposition furnace respectively. The ceramic deposition chamber is placed in the deposition area furnace body of the chemical vapor deposition furnace. The chemical vapor deposition furnace is evacuated to a vacuum degree of less than or equal to 400 Pa.

[0007] (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 300-350℃ at a rate of 5-10℃ / min, the furnace body containing the second crucible is heated to 550-650℃ at a rate of 20-30℃ / min, and the furnace body in the deposition area is heated to 580-680℃ at a rate of 25-35℃ / min.

[0008] (3) After each furnace body is heated to the predetermined temperature and kept at that temperature for 1 to 3 hours, sulfur-carrying gas is introduced into the first crucible and zinc-carrying gas is introduced into the second crucible. The sulfur-carrying gas is composed of argon and hydrogen, and the zinc-carrying gas is argon.

[0009] (4) After the reaction is complete, turn off the power to each furnace, cool down and then open the furnace to collect the nano zinc sulfide powder.

[0010] In some embodiments of this application, the purity of the sulfur powder is >99%, and the purity of the zinc powder is >99%.

[0011] In some embodiments of this application, the mass ratio of sulfur powder to zinc powder is 1:2 to 1:4, preferably 1:2.5 to 1:3.

[0012] In some embodiments of this application, the gas volumetric flow rate of the zinc-carrying gas is Q. Zn L / min, the gas volumetric flow rate of sulfur-carrying gas is Q S L / min, satisfying: 0.5 Zn / Q S <1.

[0013] In some embodiments of this application, the gas volumetric flow rate Q of the zinc-carrying gas Zn The flow rate is from 0.5 L / min to 2.5 L / min.

[0014] In some embodiments of this application, the gas volumetric flow rate Q of the sulfur-carrying gas S The flow rate is from 1 L / min to 3 L / min.

[0015] In some embodiments of this application, the gas volume flow rate of argon in the sulfur-carrying gas is Q. Ar L / min, the gas volume flow rate ratio of hydrogen in the sulfur-carrying gas is Q H L / min, satisfying: 1≤Q Ar / Q H ≤2.

[0016] In some embodiments of this application, the sulfur-carrying gas and zinc-carrying gas are shut off when the furnace temperature in the deposition zone is <200°C, and the furnace is opened to collect nano-zinc sulfide powder when the furnace temperature in the deposition zone is <40°C.

[0017] A second aspect of this application provides a nano-zinc sulfide powder prepared by the preparation method provided in this application.

[0018] ​This application provides a method for preparing nano-zinc sulfide powder and its product. Sulfur powder and zinc powder are respectively loaded into a first crucible and a second crucible. The first and second crucibles are placed in different furnace bodies of a chemical vapor deposition (CVD) furnace. A ceramic deposition chamber is placed in the deposition zone of the CVD furnace. The CVD furnace is evacuated to a vacuum level less than or equal to 400 Pa. At room temperature, the furnace body containing the first crucible is heated to 300-350°C at a rate of 5-10°C / min. The furnace containing the second crucible is heated to 550-650℃ at a rate of 20-30℃ / min, and the furnace in the deposition area is heated to 580-680℃ at a rate of 25-35℃ / min. After all furnaces have reached the predetermined temperature and been held for 1-3 hours, sulfur-carrying gas is introduced into the first crucible, and zinc-carrying gas is introduced into the second crucible. The sulfur-carrying gas consists of argon and hydrogen, and the zinc-carrying gas is argon. After the reaction is complete, the power to each furnace is turned off, and after cooling, the furnace is reopened to collect the nano-zinc sulfide powder. The method for preparing nano-zinc sulfide powder in this application uses readily available and inexpensive raw materials, making it easy to achieve industrial production. The nano-zinc sulfide powder prepared according to the method of this application has the characteristics of high purity, white appearance, and uniform size.

[0019] Of course, implementing any product or method of this application does not necessarily require achieving all of the advantages described above at the same time. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0021] Figure 1 X-ray diffraction pattern of zinc sulfide standard card;

[0022] Figure 2 The X-ray diffraction pattern of Example 1;

[0023] Figure 3 This is a transmission electron microscope image of Example 1;

[0024] Figure 4 The X-ray diffraction pattern of Example 2;

[0025] Figure 5 This is a transmission electron microscope image of Example 2;

[0026] Figure 6 This is a product appearance diagram of Example 3. Detailed Implementation

[0027] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art based on this application are within the scope of protection of this application.

[0028] Currently, methods for preparing nano-zinc sulfide powder are categorized into liquid-phase, solid-phase, and gas-phase methods. Liquid-phase methods, such as hydrothermal methods, have been extensively studied. While hydrothermal methods yield products with relatively uniform size, industrial production is challenging, and they generate significant waste liquid, causing environmental pollution. Solid-phase methods typically involve grinding zinc salts with sodium sulfide to gradually generate nano-zinc sulfide, but the resulting nano-zinc sulfide particles tend to have inconsistent sizes, and incomplete reactions are a concern. Chemical vapor deposition (CVD) is mostly used for preparing zinc sulfide films, with limited research on its application in preparing nano-zinc sulfide powder. Based on these issues, this application provides a method for preparing nano-zinc sulfide powder and its product.

[0029] The first aspect of this application provides a method for preparing nano-zinc sulfide powder, which includes the following steps:

[0030] (1) Sulfur powder and zinc powder are loaded into the first crucible and the second crucible respectively. The first crucible and the second crucible are placed in different furnace bodies of the chemical vapor deposition furnace respectively. The ceramic deposition chamber is placed in the deposition area furnace body of the chemical vapor deposition furnace. The chemical vapor deposition furnace is evacuated to a vacuum degree of less than or equal to 400 Pa.

[0031] (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 300-350℃ at a rate of 5-10℃ / min, the furnace body containing the second crucible is heated to 550-650℃ at a rate of 20-30℃ / min, and the furnace body in the deposition area is heated to 580-680℃ at a rate of 25-35℃ / min.

[0032] (3) After each furnace body is heated to the predetermined temperature and kept at that temperature for 1 to 3 hours, sulfur-carrying gas is introduced into the first crucible and zinc-carrying gas is introduced into the second crucible. The sulfur-carrying gas is composed of argon and hydrogen, and the zinc-carrying gas is argon.

[0033] (4) After the reaction is complete, turn off the power to each furnace, cool down and then open the furnace to collect the nano zinc sulfide powder.

[0034] The inventors of this application discovered that when the deposition furnace pressure is less than or equal to 400 Pa, the boiling points of zinc powder and sulfur powder decrease, and sulfur vapor reacts with hydrogen gas to generate hydrogen sulfide gas. Under the influence of inert argon gas, zinc vapor reacts with hydrogen sulfide gas to generate zinc sulfide. The presence of argon and hydrogen gas reduces the possibility of zinc oxide impurities forming in the product. This application, by controlling the furnace temperature in the deposition zone at 580-680℃, facilitates the deposition of zinc sulfide within the furnace, easily generating uniformly sized nano-zinc sulfide powder.

[0035] In some embodiments of this application, the purity of sulfur powder is >99%, and the purity of zinc powder is >99%. The inventors of this application have discovered that when high-purity zinc powder and sulfur powder are selected as raw materials, the generation of other impurities in the product nano zinc sulfide powder is suppressed, thereby improving the purity of the product nano zinc sulfide powder.

[0036] In some embodiments of this application, the mass ratio of sulfur powder to zinc powder is 1:2 to 1:4, preferably 1:2.5 to 1:3. The inventors of this application have discovered that when the mass ratio of sulfur powder to zinc powder is controlled within the above range, a larger ratio can enrich Zn atoms, allowing hydrogen sulfide to react more thoroughly with Zn, while simultaneously inhibiting the decomposition of hydrogen sulfide gas.

[0037] This application does not impose any particular restrictions on the quality of zinc powder and sulfur powder added, as long as the above-mentioned mass ratio of sulfur powder to zinc powder is met within the capacity of the chemical vapor deposition furnace, the purpose of this application can be achieved.

[0038] In some embodiments of this application, the gas volumetric flow rate of the zinc-carrying gas is Q. Zn L / min, the gas volumetric flow rate of sulfur-carrying gas is Q S L / min, satisfying: 0.5 Zn / Q S <1. Without being limited to any particular theory, controlling the gas volume flow rate of zinc-carrying gas and the gas volume flow rate of sulfur-carrying gas within the above-mentioned range can better control the formation of nano-zinc sulfide powder.

[0039] In some of the proposed implementation schemes, the gas volume flow rate Q of the zinc carrier gas is... Zn The flow rate should be between 0.5 L / min and 2.5 L / min. Controlling the gas volumetric flow rate of the zinc carrier gas within this range allows for better control of the formation rate of zinc sulfide and the formation of nano-zinc sulfide powder structures. Insufficient or excessive flow rate of the zinc carrier gas will affect the formation of nano-zinc sulfide powder.

[0040] In some embodiments of this application, the gas volumetric flow rate Q of the sulfur-carrying gas S ​The flow rate should be between 1 L / min and 3 L / min. Controlling the gas volumetric flow rate of the sulfur-carrying gas within this range allows for better control of the zinc sulfide formation rate.

[0041] In some embodiments of this application, the gas volume flow rate of argon in the sulfur-carrying gas is Q. Ar L / min, the gas volume flow rate ratio of hydrogen in the sulfur-carrying gas is Q H L / min, satisfying: 1≤Q Ar / Q H ≤2. The inventors of this application have discovered that the formation of zinc sulfide requires the presence of a reducing gas. By introducing inert gas argon and reducing gas hydrogen, the possibility of zinc oxide being formed due to the presence of a small amount of oxygen can be reduced, thereby further improving the purity of the zinc sulfide product.

[0042] This application does not impose any particular restrictions on the reaction time before turning off the furnace power in (4). The reaction time is determined according to the amount of raw materials added, as long as the purpose of this application can be achieved.

[0043] In some embodiments of this application, the sulfur-carrying gas and zinc-carrying gas are shut off when the furnace temperature in the deposition zone is below 200°C, and the furnace is opened to collect nano-zinc sulfide powder when the furnace temperature in the deposition zone is below 40°C. The phrase "furnace temperature in the deposition zone below 200°C" means the furnace temperature only needs to be below 200°C, for example, 199°C, 198°C, 195°C, 190°C, etc. Similarly, "furnace temperature in the deposition zone below 40°C" means the furnace temperature only needs to be below 40°C, for example, 39°C, 38°C, 37°C, 35°C, etc. Controlling the temperatures for shutting off the sulfur-carrying gas and zinc-carrying gas and the temperatures for furnace opening and collection within the above ranges can reduce the formation of other impurities in the nano-zinc sulfide powder and improve its purity.

[0044] The second aspect of this application provides a nano-zinc sulfide powder prepared by the preparation method provided in this application. The nano-zinc sulfide powder provided in this application has high purity, a white appearance, and uniform size.

[0045] Example

[0046] The embodiments and comparative examples provided below illustrate the implementation of this application in more detail. Various tests and evaluations were conducted according to the methods described below. Furthermore, unless otherwise specified, "parts" and "%" are quality standards.

[0047] Test methods and equipment:

[0048] X-ray diffraction analysis:

[0049] This application uses an X-ray diffraction (XRD) analyzer to analyze the crystal structure of the nano zinc sulfide powder in the examples. The test conditions are: instrument model Rigaku SmartLab, Cu target 9kW, range 5-90°, and scanning speed of 5° / min.

[0050] Transmission electron microscopy observation:

[0051] This application employs transmission electron microscopy (TEM) to analyze the microstructure of the nano-zinc sulfide powder in the examples. The testing conditions were as follows: instrument model JEM-F200 (JEOL, Japan Electronics Corporation). The nano-zinc sulfide powder in the examples was first ultrasonically dispersed in anhydrous ethanol before TEM analysis.

[0052] X-ray fluorescence spectroscopy analysis:

[0053] This application uses X-ray fluorescence spectrometry (XRF) to analyze the composition of the nano-zinc sulfide powder in Example 3. The instrument model is Panaco AXIOS. The nano-zinc sulfide powder in the example was pressed into discs with a diameter of 25 mm before analysis.

[0054] Example 1

[0055] (1) Put 10 kg of sulfur powder into the first crucible and 30 kg of zinc powder into the second crucible. Place the first crucible and the second crucible into different furnace bodies of the chemical vapor deposition furnace respectively. Place the ceramic deposition chamber into the deposition area furnace body of the chemical vapor deposition furnace and evacuate the chemical vapor deposition furnace to a vacuum degree of 400 Pa.

[0056] (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 300°C at a rate of 6°C / min, the furnace body containing the second crucible is heated to 600°C at a rate of 20°C / min, and the furnace body in the deposition area is heated to 610°C at a rate of 25°C / min.

[0057] (3) After each furnace body is heated to the predetermined temperature and kept at the temperature for 1 hour, argon and hydrogen are introduced into the first crucible, wherein the gas volume flow rate of argon is 1 L / min and the gas volume flow rate of hydrogen is 1 L / min. Argon is introduced into the second crucible, wherein the gas volume flow rate of argon is 1.8 L / min.

[0058] (4) After the reaction for 24 hours, the power supply to each furnace is turned off directly. When the furnace temperature is 190°C, the sulfur-carrying gas and zinc-carrying gas are turned off. When the furnace temperature is 35°C, the furnace is turned on and collected using a collection bag to obtain nano zinc sulfide powder.

[0059] Example 2

[0060] (1) Put 20 kg of sulfur powder into the first crucible and 50 kg of zinc powder into the second crucible. Place the first crucible and the second crucible into different furnace bodies of the chemical vapor deposition furnace respectively. Place the ceramic deposition chamber into the deposition area furnace body of the chemical vapor deposition furnace and evacuate the chemical vapor deposition furnace to a vacuum degree of 400 Pa.

[0061] (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 325°C at a rate of 8°C / min, the furnace body containing the second crucible is heated to 620°C at a rate of 25°C / min, and the furnace body in the deposition area is heated to 620°C at a rate of 30°C / min.

[0062] (3) After each furnace body is heated to the predetermined temperature and kept at the temperature for 1 hour, argon and hydrogen are introduced into the first crucible, wherein the gas volume flow rate of argon is 1.5 L / min and the gas volume flow rate of hydrogen is 1 L / min. Argon is introduced into the second crucible, wherein the gas volume flow rate of argon is 2 L / min.

[0063] (4) After reacting for 72 hours, the power supply to each furnace is turned off directly. When the furnace temperature is 190°C, the sulfur-carrying gas and zinc-carrying gas are turned off. When the furnace temperature is 35°C, the furnace is turned on and collected using a collection bag to obtain nano zinc sulfide powder.

[0064] Example 3

[0065] (1) 35 kg of sulfur powder is loaded into the first crucible and 100 kg of zinc powder is loaded into the second crucible. The first crucible and the second crucible are placed in different furnace bodies of the chemical vapor deposition furnace, respectively. The ceramic deposition chamber is placed in the deposition area furnace body of the chemical vapor deposition furnace, and the chemical vapor deposition furnace is evacuated to a vacuum degree of 400 Pa.

[0066] (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 330°C at a rate of 10°C / min, the furnace body containing the second crucible is heated to 630°C at a rate of 30°C / min, and the furnace body in the deposition area is heated to 580°C at a rate of 30°C / min.

[0067] (3) After each furnace body is heated to the predetermined temperature and kept at that temperature for 1 hour, argon and hydrogen are introduced into the first crucible, wherein the gas volume flow rate of argon is 1.5 L / min and the gas volume flow rate of hydrogen is 1.5 L / min. Argon is introduced into the second crucible, wherein the gas volume flow rate of argon is 2.5 L / min.

[0068] (4) After reacting for 160 hours, the power supply to each furnace is turned off directly. When the furnace temperature is 190°C, the sulfur-carrying gas and zinc-carrying gas are turned off. When the furnace temperature is 35°C, the furnace is turned on and collected using a collection bag to obtain nano zinc sulfide powder.

[0069] from Figure 2 and Figure 1The comparison shows that, with Figure 1 According to the comparison with the standard card of zinc sulfide, the XRD pattern in Example 1 shows that the main component of the product is zinc sulfide. Figure 3 The image shown is a transmission electron microscope (TEM) image of Example 1. Figure 3 It can be seen that the nano zinc sulfide powder in Example 1 has a uniform size, all around 100 nm.

[0070] from Figure 4 and Figure 1 The comparison shows that, compared with the zinc sulfide standard card, the XRD pattern in Example 2 indicates that the main components of the product are cubic zinc sulfide and a small amount of hexagonal zinc sulfide. From Figure 5 It can be seen that the nano zinc sulfide powder in Example 2 has a uniform size, all around 100 nm.

[0071] from Figure 6 As can be seen, the nano-zinc sulfide powder obtained in Example 3 is white in appearance. Furthermore, XRF analysis shows that the nano-zinc sulfide powder in Example 3 contains only zinc and sulfur elements, with a zinc content of 65.43% by mass and a sulfur content of 34.563% by mass. The purity of the nano-zinc sulfide powder is 99.996%, indicating high purity of the obtained product.

[0072] As can be seen from the above embodiments, the preparation method of nano zinc sulfide powder provided in this application uses readily available and inexpensive raw materials, and the operation steps are relatively simple, making it easy to achieve industrial production. The nano zinc sulfide powder prepared by the preparation method provided in this application has the characteristics of high purity, white appearance and uniform size, which meets the requirements of high-quality nano zinc sulfide powder.

[0073] It should be noted that, in this document, the terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0074] The above description is merely a preferred embodiment of this application and is not intended to limit the scope of protection of this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application are included within the scope of protection of this application.

Claims

1. A method for preparing nano-zinc sulfide powder, wherein, The preparation method includes: (1) Sulfur powder and zinc powder are respectively loaded into the first crucible and the second crucible. The first crucible and the second crucible are respectively placed in different furnace bodies of the chemical vapor deposition furnace. The ceramic deposition chamber is placed in the deposition area furnace body of the chemical vapor deposition furnace. The chemical vapor deposition furnace is evacuated to a vacuum degree of less than or equal to 400 Pa. (2) Under room temperature conditions, the furnace body containing the first crucible is heated to 300-350°C at a rate of 5-10°C / min, the furnace body containing the second crucible is heated to 550-650°C at a rate of 20-30°C / min, and the furnace body of the deposition area is heated to 580-680°C at a rate of 25-35°C / min. (3) After all furnace bodies have been heated to the predetermined temperature and held for 1 to 3 hours, sulfur-carrying gas is introduced into the first crucible and zinc-carrying gas is introduced into the second crucible. The sulfur-carrying gas is composed of argon and hydrogen, and the zinc-carrying gas is argon. The gas volume flow rate of the zinc-carrying gas is Q. Zn L / min, the gas volumetric flow rate of the sulfur-carrying gas is Q. S L / min, satisfying: 0.5 Zn / Q S <1, the gas volumetric flow rate Q of the zinc-carrying gas Zn The gas volumetric flow rate Q of the sulfur-carrying gas is 1.8 L / min to 2.5 L / min. S The flow rate is 2.5 L / min to 3 L / min;​ (4) After the reaction is complete, turn off the power to each furnace, cool down and then open the furnace to collect the nano zinc sulfide powder.

2. The preparation method according to claim 1, wherein, The purity of the sulfur powder is >99%, and the purity of the zinc powder is >99%.

3. The preparation method according to claim 1, wherein, The mass ratio of sulfur powder to zinc powder is 1:2 to 1:

4.

4. The preparation method according to claim 1, wherein, The mass ratio of sulfur powder to zinc powder is 1:2.5 to 1:

3.

5. The preparation method according to claim 1, wherein, The gas volume flow rate of argon in the sulfur-carrying gas is Q. Ar The gas volume flow rate of hydrogen in the sulfur-carrying gas is Q, where L / min is the flow rate. H L / min, satisfying: 1≤Q Ar / Q H ≤2.

6. The preparation method according to claim 1, wherein, When the furnace temperature in the deposition zone is <200℃, the sulfur-carrying gas and the zinc-carrying gas are shut off; when the furnace temperature in the deposition zone is <40℃, the furnace is opened to collect the nano-zinc sulfide powder.

7. A nano zinc sulfide powder prepared by any one of claims 1 to 6.

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