Preparation device and method of Ti3O5 powder material

Abstract

The invention discloses a preparation device and method of a Ti3O5 powder material, and belongs to the technical field of preparation of oxide functional powder materials. TiO2 powder is used as a raw material, sodium chloride-potassium chloride-calcium chloride is used as an electrolyte, zinc and / or tin is used as a cathode, and a graphite rod is used as an anode; and a zinc-stann-TiO2 powder-chlorine salt sandwich type electrolysis device system is constructed through density difference, so that TiO2 powder is directly electrolyzed to prepare a Ti3O5 powder material. According to the device and the method, the traditional Ti3O5 powder material preparation process flow is greatly shortened, and the zinc-tin cathode and the electrolyte can be repeatedly used, so that the cost is greatly reduced; in the electrolysis process, side reactions are few, the reaction process is environmentally friendly, no harmful substance is discharged, and the prepared Ti3O5 powder material is high in purity.

Description

Technical Field

[0001] The present application relates to the field of preparation of oxide functional powder materials, and relates to a method and device for preparing titanium pentoxide (Ti3O5) powder materials using low-cost titanium dioxide (TiO2), and in particular to a device and method for preparing Ti3O5 powder materials. Background Art

[0002] Ti3O5 is a metal oxide with unique phase change properties and a melting point as high as 2180°C. As a novel phase change material, Ti3O5 undergoes a bistable metal-semiconductor phase transition when exposed to external stimuli such as light, heat, pressure, and electric current. This phase transition is accompanied by changes in the material's physical properties, such as electrical conductivity and magnetic properties, as well as the absorption and release of energy. In the field of data storage, this phase change property enables Ti3O5 to be used in the development of high-density, fast-response data storage devices, potentially increasing data storage capacity and read / write speeds. In thermal storage, its energy absorption and release properties can be used to develop efficient thermal storage materials, improving energy efficiency. In the field of optoelectronic devices, Ti3O5's optoelectronic properties offer potential applications in photoelectric conversion and light detection, allowing it to be used in the manufacture of high-performance optoelectronic devices. Furthermore, in the field of vacuum coating, Ti3O5 is a high-refractive-index material for visible and infrared spectroscopy. It can be used to deposit Ti3O5 thin films in optical coatings, supporting the performance improvement of optical devices.

[0003] Currently, the preparation methods of Ti3O5 have many limitations. Earlier methods have used high-temperature sintering to reduce nano-titanium dioxide powder to produce λ-Ti3O5 powder. However, this method is costly, dangerous, complex, and has low yields and production efficiency. For example, patent CN111217390B provides a method for preparing λ-Ti3O5 powder, which includes: adding butyl titanate or propyl titanate to stirred anhydrous ethanol under heating conditions and continuously stirring until uniformly mixed to obtain a first mixture; adding polyethylene glycol to the stirred first mixture and continuously stirring until uniformly mixed to obtain a second mixture; drying the second mixture to obtain a gel; and sintering the gel at 1050°C to 1100°C under an inert atmosphere for 2 to 6 hours, cooling it to room temperature in air, and grinding it to obtain λ-Ti3O5 powder. This patented preparation method involves high-temperature sintering and other operations, which are costly and dangerous. There are also methods for preparing λ-Ti3O5 powder using carbothermal reduction, but this method requires coating the nano-titanium dioxide with a layer of inorganic material, which is cumbersome and costly. Patent CN104973622B provides a method for preparing λ-Ti3O5, a photoinduced phase change memory material. Nano-TiO2 powder with a particle size of less than 100 nm, pretreated with an aluminate or zirconate coupling agent, is used as the raw material. This is then evenly dispersed with a carbonaceous reducing agent in a mixed medium and dried to obtain a mixed powder. The mixed powder is then pressed into blocks and reduced at 900-1250°C in a nitrogen or argon atmosphere for 0.5-6 hours before being cooled to room temperature.

[0004] These existing preparation methods struggle to meet the market's demand for large-scale, high-quality Ti3O5 powder. On the one hand, high costs limit its widespread application, especially in cost-sensitive applications. On the other hand, complex processes and low yields make the supply of Ti3O5 powder unstable, making it difficult to meet the growing market demand. Therefore, there is a need for a safer, more reliable, simpler, lower-cost, and more efficient method for preparing Ti3O5 powder. Summary of the Invention

[0005] Based on the above shortcomings of the prior art, the purpose of this application is to provide a device and method for preparing Ti3O5 powder material.

[0006] This application uses TiO2 powder as the raw material, sodium chloride-potassium chloride-calcium chloride as the electrolyte, and zinc and tin as the cathode. By leveraging density differences to construct a "zinc-tin-TiO2 powder-chloride salt" sandwich electrolysis system, TiO2 powder can be directly electrolyzed to produce Ti3O5 powder. This application significantly shortens the traditional Ti3O5 powder preparation process, and the zinc-tin and chloride salt materials can be reused, significantly reducing costs. The electrolysis process has few side reactions, making it environmentally friendly and free of harmful emissions. The resulting Ti3O5 powder is of high purity.

[0007] This application provides the following technical solutions:

[0008] The technical solution of the present application provides a method for preparing Ti3O5 powder material, which is based on a "sandwich" electrolysis device and includes the following steps:

[0009] (a) zinc particles and tin particles are evenly placed at the bottom of a container of an electrolysis device to form a zinc-tin layer; TiO2 powder is placed on top of the zinc-tin layer to form a raw material layer; sodium chloride, potassium chloride, and calcium chloride are evenly mixed and placed on top of the raw material layer to form a chloride layer, thereby obtaining a "zinc-tin-TiO2 powder-chloride" three-layer system;

[0010] (b) sealing the container described in step (a) with a container cover, introducing an inert gas protection, and heating the "zinc tin-TiO2 powder-chloride salt" system to a target temperature;

[0011] (c) When the "zinc-tin-TiO2 powder-chloride salt" three-layer system is in a molten state, a graphite rod is inserted into the container through a hole in the container lid and placed in the chloride salt layer to serve as an anode; a molybdenum wire is inserted through a hole in the side wall of the container and placed in the zinc-tin layer, with the zinc-tin layer serving as a cathode and the molybdenum wire being used for electrical conduction; a power supply is connected between the graphite rod and the molybdenum wire, the power supply is turned on, and a voltage is applied between the cathode and the anode to perform electrolysis to obtain an electrolysis product;

[0012] (d) removing the electrolytic product obtained in the above step (c) from the container, separating the solidified chloride layer and the zinc-tin layer to obtain a powder product of the raw material layer, and washing the powder product with hydrochloric acid and deionized water in sequence, and drying it to finally obtain the Ti3O5 powder material.

[0013] Furthermore, the "sandwich" type electrolysis device comprises:

[0014] a container and a container lid, both of which can be sealed and used for the reaction;

[0015] The air inlet pipe and the air outlet pipe are connected to the interior of the container through the container cover;

[0016] A graphite rod, a molybdenum wire, and a power supply; the graphite rod serves as the anode for the electrolytic reaction, and the molybdenum wire serves as a conductive wire connecting the cathode and the anode; one end of the graphite rod and the molybdenum wire are placed inside the container, and the other end is arranged outside the container and connected to the positive and negative electrodes of the power supply, respectively;

[0017] The heating wire is spirally arranged around the circumference of the container and is used for heating and melting the chloride salt layer, the raw material layer and the zinc-tin layer inside the container.

[0018] Furthermore, the air inlet pipe and the air outlet pipe are respectively provided with valves; the valves are always kept open during the reaction to allow the protective gas to enter;

[0019] Furthermore, the container cover is provided with a hole for passing the graphite rod; the container side wall is provided with a hole for passing the molybdenum wire; and sealing gaskets are provided at the above holes to maintain sealing;

[0020] Furthermore, the material of the container is quartz or corundum; the shape of the container is not specifically limited, and can be preferably any one of cylindrical, rectangular or spherical, to ensure that the various materials can be spread over the container after being heated and melted to form a stable "zinc tin-TiO2 powder-chloride salt" three-layer structure;

[0021] Furthermore, the outside of the air inlet pipe is connected to an inert gas generating device;

[0022] Furthermore, the heating wire is connected to a heating power source.

[0023] Furthermore, the mass fraction ratio between the zinc particles and the tin particles in step (a) is (0-99%): (0-99%), and the sum of the mass fractions of the two is 100%; the mass fraction ratio is preferably (1:1) to (3:1), more preferably 1:1 or 3:1; in the chloride salt layer in step (a), the mass fraction ratio between sodium chloride, potassium chloride, and calcium chloride is (0-99%): (0-99%): (0-99%), and the sum of the mass fractions of the three is 100%;

[0024] Furthermore, in step (a), the mass fraction ratio of the zinc-tin layer, the raw material layer, and the chloride salt layer is (1-99%): (1-99%): (1-99%), and the sum of the mass fractions of the three is 100%;

[0025] Furthermore, the inert gas in step (b) is preferably nitrogen or argon; the target temperature in step (b) is 550-850°C;

[0026] Furthermore, the voltage in step (c) is 1.0 to 3.0 V; the electrolysis time in step (c) is 5 to 20 hours;

[0027] Furthermore, the chloride layer and zinc-tin layer obtained in step (d) are used in steps (a) to (c) to achieve recycling.

[0028] Compared with the existing technology, this application has the following characteristics and advantages:

[0029] 1. This application utilizes a unique "zinc-tin-TiO2 powder-chloride salt" sandwich electrolysis device structure. By utilizing density differences to create a three-layer electrolysis reaction system, this approach, unlike traditional complex preparation processes, provides a novel approach and method for preparing Ti3O5 powder materials. This unique structural setup facilitates efficient reactions between the various substances during the electrolysis process, improving the efficiency and specificity of the reaction.

[0030] 2. Using TiO2 powder as the raw material, sodium chloride-potassium chloride-calcium chloride as the electrolyte, and zinc and tin as the cathode, this carefully designed raw material and electrolyte combination fully utilizes the characteristics of each substance, achieving efficient conversion of TiO2 powder to Ti3O5 powder during the electrolysis process. This method features simple operation, a short process flow, controllable product morphology, and high added value, facilitating industrial production.

[0031] 3. The device provided herein features an external cathode, which facilitates assembly and disassembly of the structure while also preventing direct contact between the cathode and the two layers of material above. Some prior art devices utilize multiple stacked containers to hold materials, resulting in a complex structure. This device simplifies this structure by utilizing an external cathode. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The present application provides a schematic diagram of an apparatus for preparing Ti3O5 powder material in Example 1;

[0033] Figure 2 X-ray diffraction pattern of Ti3O5 powder material prepared in Example 1 of the present application;

[0034] Figure 3 This application prepares the SEM image of the fibrous Ti3O5 powder material in Example 2;

[0035] Figure 4 Macroscopic photograph of Ti3O5 powder material prepared in Example 3 of this application;

[0036] Reference numerals:

[0037] 1 container, 2 container cover, 3 air inlet pipe, 4 air outlet pipe, 5 graphite rod, 6 heating wire, 7 molybdenum wire, 8 chloride layer, 9 raw material layer, 10 zinc-tin layer, 11 power supply. DETAILED DESCRIPTION

[0038] In order to enable those skilled in the art to better understand the technical solutions of the present application, the present application is described in detail below with reference to specific embodiments. It should be noted that the following embodiments will help those skilled in the art to further understand the present application, but do not limit the present application in any form. It should be noted that, for those of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application. These all fall within the scope of protection of the present application.

[0039] All raw materials in this application are not particularly limited in their sources and can be purchased from the market or prepared according to conventional methods well known to those skilled in the art.

[0040] The following embodiments are all based on a "sandwich" type electrolysis device, which is a sealed electrolysis device. The main part of the device is a container 1 and a container cover 2, which are sealed and used for reaction. During the reaction, the material inside the container 1 forms a stable "zinc-tin-TiO2 powder-chloride salt" three-layer structure from bottom to top, namely, zinc-tin layer 10-raw material layer 9-chloride salt layer 8, and is in a molten state.

[0041] The container lid 2 has three holes for connecting the air inlet pipe 3, the air outlet pipe 4, and the graphite rod 5. A hole is provided in the sidewall of the container 1 for connecting a molybdenum wire 7. One end of the graphite rod 5 is inserted into the chloride layer 8, while one end of the molybdenum wire 7 is inserted into the zinc-tin layer 10. The other ends of the graphite rod 5 and molybdenum wire 7 are located outside the container 1 and connected to the positive and negative electrodes of a power supply 11, respectively. In the reaction system, the chloride layer 8 serves as the electrolyte, the graphite rod 5 serves as the anode, and the zinc-tin layer 10 serves as the cathode.

[0042] The heating wire 6 is spirally arranged around the circumference of the container 1 and is connected to a heating power source for heating and melting the chloride layer 8, the raw material layer 9 and the zinc-tin layer 10 inside the container 1.

[0043] Example 1:

[0044] (a) A quartz crucible with an inner diameter of 6 cm was used as container 1. 100 g of zinc granules and 100 g of tin granules were placed at the bottom of the quartz crucible. 50 g of TiO2 powder was added, followed by a mixed salt of sodium chloride (50 g), potassium chloride (50 g), and calcium chloride (550 g).

[0045] (b) Turn on the heating power supply to make the heating wire 6 work, and introduce high-purity nitrogen to protect the temperature and raise it to 750℃. Due to the density effect of each component, a clear "zinc-tin-TiO2 powder-chloride salt" three-layer structure will be formed, such as Figure 1 shown.

[0046] (c) A graphite rod 5 was inserted into molten sodium chloride-potassium chloride-calcium chloride as the anode, and a molybdenum wire 7 was connected to the liquid zinc-tin layer 10 through the outside of the crucible as the cathode. A constant voltage of 2.0 V was applied to the anode and cathode, and electrolysis was performed for 10 hours to obtain an electrolysis product.

[0047] (d) The cooled crucible is then taken out and the solidified zinc-tin layer 10 and chloride layer 8 are removed to obtain a powder product. The powder product is washed with dilute hydrochloric acid and deionized water to obtain the final Ti3O5 product, whose X-ray diffraction pattern is as follows: Figure 2 As shown, there is an obvious characteristic peak of Ti3O5 single phase, which fully proves that the method and device proposed in this application can effectively prepare Ti3O5 powder material.

[0048] Example 2:

[0049] (a) A corundum crucible with an inner diameter of 8 cm was used as a container. 150 g of zinc particles and 50 g of tin particles were placed at the bottom of the crucible. 60 g of TiO2 powder (fibrous in microscopic appearance) was added, followed by a mixed salt of sodium chloride (300 g), potassium chloride (50 g), and calcium chloride (250 g).

[0050] (b) Turn on the heating power supply to make the heating wire 6 work, and introduce high-purity argon gas to protect and heat up to 600°C to form a clear "zinc-tin-TiO2 powder-chloride salt" three-layer structure.

[0051] (c) A graphite rod 5 was inserted into molten sodium chloride-potassium chloride-calcium chloride as the anode, and a molybdenum wire 7 was connected to the liquid zinc-tin layer 10 through the outside of the crucible as the cathode. A constant voltage of 2.2 V was applied to the anode and cathode, and electrolysis was performed for 15 hours to obtain an electrolysis product.

[0052] (d) The cooled crucible is then taken out and the solidified zinc-tin layer 10 and chloride layer 8 are removed to obtain a powder product. The powder product is washed with dilute hydrochloric acid and deionized water to obtain the final Ti3O5 product, whose microscopic morphology is as follows: Figure 3 As shown, the typical fiber morphology is consistent with the microscopic morphology of the raw material, which fully proves that the method and device proposed in this application can effectively design and prepare Ti3O5 powder materials with special morphology.

[0053] Example 3: Repeat the melting and electrolysis process twice

[0054] (a) A corundum crucible with an inner diameter of 5 cm was used as a container. 100 g of zinc granules and 100 g of tin granules were placed at the bottom of the corundum crucible. 30 g of TiO2 powder was added, followed by a mixed salt of sodium chloride (100 g), potassium chloride (100 g), and calcium chloride (100 g).

[0055] (b) Turn on the heating power supply to make the heating wire 6 work, and introduce high-purity nitrogen to protect the temperature and raise it to 650°C to maintain the temperature, forming a clear "zinc-tin-TiO2 powder-chloride salt" three-layer structure.

[0056] (c) A graphite rod 5 was inserted into molten sodium chloride-potassium chloride-calcium chloride as the anode, and a molybdenum wire 7 was connected to the liquid zinc-tin layer 10 through the outside of the crucible as the cathode. A constant voltage of 2.5 V was applied to the anode and cathode, and electrolysis was performed for 10 hours to obtain an electrolysis product.

[0057] (d) The cooled crucible is then removed, and a powder product is obtained after removing the solidified zinc-tin layer 10 and the chloride salt layer 8. The powder product is washed with dilute hydrochloric acid and deionized water to obtain the first batch of Ti3O5 product.

[0058] (e) The collected solidified zinc-tin layer 10 is placed back into a corundum crucible with a diameter of 5 cm, 30 g of TiO2 powder is added, and then the collected solidified chloride salt layer 8 is added.

[0059] (f) Turn on the heating power supply, activate the heating wire 6, and introduce high-purity nitrogen gas to raise the temperature to 650°C and maintain the temperature, continuing to form the "zinc-tin-TiO2 powder-chloride salt" three-layer structure. Repeat steps (c) to (d) to obtain a second batch of Ti3O5 product.

[0060] In this embodiment, Ti3O5 is continuously generated by repeating the electrolysis process. The macroscopic morphology of the Ti3O5 products obtained in the first and second batches is as follows: Figure 4 As shown, they all have typical blue-black characteristics, which fully proves that the method and device proposed in this application can effectively and continuously produce Ti3O5 powder materials.

[0061] In summary, based on the significant application value of TiO powder materials and the challenges of existing preparation technologies, this application proposes a novel preparation method and apparatus, aiming to promote the research and application of TiO powder materials. By reducing production costs, improving production efficiency and product quality, this approach provides strong support for the large-scale application of TiO powder.

[0062] The research results of this application's technology will help promote the application and development of TiO in fields such as data storage, thermal storage, optoelectronic devices, and vacuum coating, providing new impetus for technological advancement and industrial upgrading in related industries. Furthermore, the successful implementation of this application's technology will also provide useful reference and inspiration for the preparation of other metal oxide powders, promoting the overall development of the metal oxide materials field.

[0063] The above description of the embodiments is intended to facilitate understanding and use of the invention by those skilled in the art. It will be apparent that those skilled in the art can readily make various modifications to these embodiments and apply the general principles described herein to other embodiments without requiring inventive effort. Therefore, this application is not limited to the above-described embodiments. Any improvements and modifications made by those skilled in the art based on the disclosure of this application, without departing from the scope of this application, should be within the scope of protection of this application.

Claims

1. A method for preparing Ti3O5 powder material, characterized in that: The method is based on a "sandwich" electrolysis device and includes the following steps: (a) zinc particles and tin particles are evenly placed on the bottom of a container (1) of an electrolysis device to form a zinc-tin layer (10); TiO2 powder is placed on top of the zinc-tin layer (10) to form a raw material layer (9); sodium chloride, potassium chloride, and calcium chloride are evenly mixed and placed on top of the raw material layer (9) to form a chloride layer (8), thereby obtaining a "zinc-tin-TiO2 powder-chloride" three-layer system; (b) adding a container cover (2) to the container (1) of step (a), sealing the container, introducing an inert gas for protection, and heating the "zinc-tin-TiO2 powder-chloride salt" system to a target temperature; (c) when the "zinc-tin-TiO2 powder-chloride" three-layer system is in a molten state, a graphite rod (5) is inserted into the container (1) through a hole on the container cover (2) and placed in the chloride layer (8) as an anode; a molybdenum wire (7) is inserted into the hole on the side wall of the container (1) and placed in the zinc-tin layer (10), the zinc-tin layer (10) serving as a cathode, and the molybdenum wire (7) is used for conducting electricity; a power supply is connected between the graphite rod (5) and the molybdenum wire (7), the power supply is turned on, and a voltage is applied between the cathode and the anode to perform electrolysis to obtain an electrolysis product; (d) removing the electrolytic product obtained in step (c) from the container (1), separating the solidified chloride layer (8) and the zinc-tin layer (10), obtaining a powder product of the raw material layer (9), and finally obtaining the Ti3O5 powder material after washing and drying the powder product.

2. The method for preparing a Ti3O5 powder material according to claim 1, wherein: The "sandwich" type electrolysis device includes the following structure: A container (1) and a container cover (2), both of which are sealed and used for reaction; the container (1) is made of quartz or corundum; The air inlet pipe (3) and the air outlet pipe (4) are connected to the interior of the container (1) through the container cover (2); A graphite rod (5), a molybdenum wire (7), and a power supply (11); the graphite rod (5) serves as an anode for electrolytic reaction, and the molybdenum wire (7) serves as a conductive wire connecting the cathode and the anode; one end of the graphite rod (5) and the molybdenum wire (7) are placed inside the container (1), and the other ends are arranged outside the container (1) and are respectively connected to the positive and negative electrodes of the power supply (11); A heating wire (6) is spirally arranged around the circumference of the container (1) for heating.

3. The method for preparing a Ti3O5 powder material according to claim 2, wherein: The air inlet pipe (3) and the air outlet pipe (4) are respectively provided with valves; The container cover (2) is provided with a hole for passing the graphite rod (5); the side wall of the container (1) is provided with a hole for passing the molybdenum wire (7); and sealing gaskets are provided at these holes to maintain sealing.

4. The method for preparing a Ti3O5 powder material according to claim 2, wherein: The outside of the air inlet pipe (3) is connected to an inert gas generating device; and the heating wire (6) is connected to a heating power source.

5. The method for preparing a Ti3O5 powder material according to claim 1, wherein: The mass fraction ratio of the zinc particles to the tin particles in step (a) is (0-99%): (0-99%), and the sum of their mass fractions is 100%.

6. The method for preparing a Ti3O5 powder material according to claim 1, wherein: In the chloride salt layer (8) of step (a), the mass fraction ratio of sodium chloride, potassium chloride and calcium chloride is (0-99%): (0-99%): (0-99%), and the sum of the mass fractions of the three is 100%.

7. The method for preparing a Ti3O5 powder material according to claim 1, wherein: The mass fraction ratio of the zinc-tin layer (10), the raw material layer (9) and the chloride salt layer (8) in step (a) is (1-99%): (1-99%): (1-99%), and the sum of the mass fractions of the three is 100%.

8. The method for preparing a Ti3O5 powder material according to claim 1, wherein: The inert gas in step (b) is nitrogen or argon; and the target temperature in step (b) is 550-850°C.

9. The method for preparing a Ti3O5 powder material according to claim 1, wherein: The voltage in step (c) is 1.0 to 3.0 V; and the electrolysis time in step (c) is 5 to 20 hours.

10. The method for preparing a Ti3O5 powder material according to claim 1, characterized in that: The chloride layer (8) and zinc-tin layer (10) obtained in step (d) are used in steps (a) to (c) for recycling.

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