Method for manufacturing black titanium dioxide photocatalyst sterilization filter and black titanium dioxide photocatalyst sterilization filter manufactured by the method

Abstract

Disclosed are a method for manufacturing a black titanium dioxide photocatalytic sterilization filter and a black titanium dioxide photocatalytic sterilization filter manufactured by the method. According to one aspect of the present embodiment, provided is a method for manufacturing a black titanium dioxide photocatalytic sterilization filter, the method comprising the steps of: applying a titanium dioxide (TiO2) solution to a porous plate to coat; applying, to the porous plate having the titanium dioxide solution coated thereon, a reducing agent solution in which a reducing agent for oxygen deficiency is dissolved, and then heating, to synthesize the titanium dioxide coating layer into a black titanium dioxide coating layer; applying a metal compound solution to the porous plate having the black titanium oxide coating layer formed thereon; and irradiating light to the porous plate having the metal compound solution applied thereto to allow a metal to be deposited on the black titanium dioxide.

Description

Method for manufacturing a black titanium dioxide photocatalytic sterilizing filter and a black titanium dioxide photocatalytic sterilizing filter manufactured by the method

[0001] The present invention relates to a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter and a black titanium dioxide photocatalytic sterilizing filter manufactured by the method, and more specifically, to a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter capable of increasing a surface area by using black titanium dioxide as a photocatalyst and greatly improving photocatalytic efficiency in visible light by depositing a metal nanomaterial on black titanium dioxide, thereby enhancing antibacterial performance, and to a black titanium dioxide photocatalytic sterilizing filter manufactured by the method.

[0002] The content described in this section merely provides background information for the present embodiment and does not constitute prior art.

[0003] Recently, as social and economic losses due to fine dust and respiratory viruses have increased, interest in removing harmful substances from the air has increased.

[0004] In particular, in many developed countries, air pollutant concentrations have risen above the Air Quality Guidelines (AQG) published by the World Health Organization (WHO). Air pollutants cause symptoms such as coughing, angina, and shortness of breath through the respiratory system, and can have long-term negative effects on various organs. Demand is growing for new antibacterial and sterilizing materials to block these air pollutants.

[0005] Conventionally, most air purification systems utilize HEPA (High Efficiency Particulate Air) filters. However, these filters suffer from low efficiency and high waste disposal costs. In particular, HEPA filters lack the selectivity and efficiency to simultaneously capture and remove various airborne pollutants, such as volatile organic compounds (VOCs), CO2, and bioaerosols.

[0006] Another method uses light to remove airborne pollutants. Most existing light-based sterilizers and antibacterial devices use ultraviolet light, such as UV lamps, as a light source. However, this method has drawbacks: high power consumption, short lamp life, and the potential for harmful effects on the human body when exposed to UV light.

[0007] To solve these problems, research into the production of antibacterial filters using photocatalysts has been actively conducted recently.

[0008] A photocatalyst is a substance that can remove harmful factors in the air (bacteria, viruses, VOCs, etc.) by forming reactive oxygen species when exposed to light. Photocatalysts include titanium dioxide (TiO2), zinc oxide (ZnO), cadmium sulfide (CdS), and tungsten oxide (WO3).

[0009] Among these photocatalysts, titanium dioxide (TiO2) photocatalyst has the advantages of high photoreactivity, chemical stability, non-toxicity, environmental friendliness, and low cost, and the hydroxyl radicals generated by the photocatalytic reaction have high oxidizing power and can oxidize harmful compounds and bacteria in the air, thereby purifying the air.

[0010] More specifically, when ultraviolet rays are irradiated on a photocatalyst, electrons and holes are generated, and the generated electrons and holes are converted into oxygen, water, and OH. - It reacts with the back to generate hydroxyl radicals. At this time, the generated hydroxyl radicals decompose organic substances by oxidizing them, thereby decomposing odorous substances, viruses, and bacteria present in the air, thereby purifying the air.

[0011] Therefore, in order to increase the sterilization efficiency of the photocatalyst, the generation of hydroxyl radicals must be increased.

[0012] Several methods have been attempted to increase the generation rate of hydroxyl radicals. For example, there is a method of increasing the generation rate of electrons and holes by depositing metal components such as platinum (Pt), gold (Au), silver (Ag), palladium (Pd), ruthenium (Ru), cobalt (Co), nickel (Ni), iron (Fe), copper (Cu), or chromium (Cr) on titanium dioxide (TiO2) photocatalytic particles, and a method of adding antibacterial metals such as silver (Ag) or copper (Cu) to exhibit antibacterial properties even in the absence of light irradiation.

[0013] Depending on whether a metal component is deposited on the photocatalyst particles and the deposition method, the generation rate of electrons and holes in the titanium dioxide (TiO2) photocatalyst varies.

[0014] Therefore, it is important to deposit a metal component on the surface of a titanium dioxide photocatalyst in an optimal manner and under optimal conditions to increase the generation rate of electrons and holes and thus increase the amount of hydroxyl radicals produced.

[0015] However, in the field of air purification using photocatalysts, most research / products still use ultraviolet light, and this is because it is difficult to develop photocatalyst materials that react effectively in visible light.

[0016] One embodiment of the present invention aims to provide a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter that can effectively react in visible light to enhance sterilizing performance, and a black titanium dioxide photocatalytic sterilizing filter manufactured by the method.

[0017] In addition, one embodiment of the present invention aims to provide a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter capable of increasing the deposition rate of a metal deposited on the surface of a photocatalyst by concentrating a metal compound on black titanium dioxide and photodepositing the metal compound, and a black titanium dioxide photocatalytic sterilizing filter manufactured by the method.

[0018] According to one aspect of the present invention, a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter is provided, comprising: a process for coating a porous plate by applying a titanium dioxide (TiO2) solution; a process for applying a reducing agent solution in which a reducing agent for oxygen deficiency is dissolved to the porous plate to which the titanium dioxide solution is applied, and then heating the solution to synthesize the titanium dioxide coating layer into a black titanium dioxide coating layer; a process for applying a metal compound solution to the porous plate on which the black titanium dioxide coating layer is formed, and a process for irradiating the porous plate to which the metal compound solution is applied with light to deposit the metal on the black titanium dioxide.

[0019] According to one aspect of the present embodiment, the method for manufacturing the black titanium dioxide photocatalytic sterilizing filter is characterized by a process of concentrating the metal compound solution through drying for a predetermined period of time after the process of applying the metal compound solution.

[0020] According to one aspect of the present embodiment, the method for manufacturing the black titanium dioxide photocatalytic sterilizing filter is characterized by further including a step of immersing the porous plate in an alcohol solution after concentrating the metal compound solution.

[0021] According to one aspect of the present embodiment, the alcohol solution is an ethanol (C2H6O) solution, and the ethanol solution is characterized in that it is prepared by mixing ethanol and distilled water in a volume ratio of 0.5 to 1.5: 8.5 to 9.5.

[0022] According to one aspect of the present embodiment, the metal compound is a gold compound, chloroauric acid (HAuCl4), and the metal compound solution is characterized in that it is a solution in which the chloroauric acid (HAuCl4) is dissolved in distilled water.

[0023] According to one aspect of the present embodiment, the molar concentration of the chloroauric acid solution is characterized by being 25 to 35 mM.

[0024] According to one aspect of the present embodiment, the light is characterized in that it is ultraviolet and has a wavelength of 300 to 400 nm.

[0025] According to one aspect of the present embodiment, a black titanium dioxide photocatalytic sterilizing filter manufactured by the above manufacturing method is provided.

[0026] According to one aspect of the present embodiment, the black titanium dioxide photocatalytic sterilizing filter is characterized in that it is activated at ultraviolet and visible light wavelengths of 200 nm to 800 nm to perform a sterilizing action.

[0027] According to one aspect of the present embodiment, an air purifier having the black titanium dioxide photocatalytic sterilizing filter is provided.

[0028] As described above, according to one aspect of the present embodiment, there is an advantage in that the sterilizing power can be greatly improved by maximizing the amount of hydroxyl radicals produced during photocatalytic action.

[0029] In addition, according to one aspect of the present embodiment, by concentrating a metal compound solution through a drying process on the surface of a plate and then photodepositing the metal to increase the deposition rate of the metal, there is an advantage in that the amount of hydroxy radicals generated can be increased when irradiating the sterilizing filter with visible light.

[0030] FIG. 1 is a flowchart illustrating a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter according to one embodiment of the present invention.

[0031] The present invention is susceptible to various modifications and embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the present invention to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the present invention. Throughout the description of each drawing, similar reference numerals have been used to designate similar components.

[0032] Terms such as first, second, A, and B may be used to describe various components, but these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The term "and / or" includes a combination of multiple related items described herein or any of multiple related items described herein.

[0033] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0034] The terminology used in this application is solely for the purpose of describing specific embodiments and is not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. It should be understood that terms such as "comprise" or "have" in this application do not preclude the presence or possibility of addition of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification.

[0035] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention belongs.

[0036] Terms defined in commonly used dictionaries should be interpreted to have a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted in an idealized or overly formal sense unless expressly defined in this application.

[0037] In addition, each configuration, process, procedure or method included in each embodiment of the present invention may be shared within a scope that is not technically inconsistent with each other.

[0038] FIG. 1 is a flowchart illustrating a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter according to one embodiment of the present invention.

[0039] Referring to FIG. 1, a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter according to an embodiment of the present invention may proceed as follows. A black titanium dioxide coating layer, which is a photocatalytic layer, may be formed on a porous plate that can be used as a sterilizing filter, and metal nanoparticles may be coated on the black titanium dioxide coating layer. Accordingly, according to a manufacturing method according to an embodiment of the present invention, even under light in the visible light wavelength range, the amount of hydroxyl radicals generated may be increased, thereby improving sterilizing power and reducing harmful effects on the human body.

[0040] In addition, the present invention can further provide a sterilizing filter manufactured using a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, and can further provide a completed air purifier comprising a fan for circulating indoor air through the sterilizing filter, a sterilizing filter, and a case housing the fan. Furthermore, the air purifier can be manufactured in any shape using the sterilizing filter of the present invention.

[0041] Additionally, the black titanium dioxide photocatalytic sterilizing filter is activated by light in the ultraviolet and visible light wavelength range of 200 nm to 800 nm to perform sterilizing action.

[0042] Hereinafter, a method for manufacturing a black titanium dioxide photocatalytic sterilizing filter of the present invention will be described in detail.

[0043] First, a titanium dioxide (TiO2) solution is applied to the porous plate to coat it (S100).

[0044] A porous plate is a substrate with numerous pores. It defines the filter's external shape and serves as a support for coating photocatalytic materials. There are no specific restrictions on the material used for the porous plate; for example, it can be made of a glass fiber substrate or a glass plate.

[0045] Additionally, titanium dioxide can be replaced by complex oxides such as tungsten oxide (WO3), zirconium oxide (ZrO2), tin oxide (SnO2), vanadium oxide (V2O3), or strontium titanate (SrTiO3) if they can deplete oxygen that can absorb visible light as a photocatalyst.

[0046] Next, a titanium dioxide coating layer was formed using a reducing agent to form black titanium dioxide (TiO 2-x , black TiO2, B-TiO2) is synthesized as a coating layer (S200).

[0047] The black titanium dioxide coating layer increases the photocatalytic efficiency by forming porosity in the titanium dioxide coating layer and causing oxygen deficiency.

[0048] Additionally, the reducing agent can be implemented as a material that can be oxidized by easily losing its outermost electrons, such as magnesium, a group 2 element.

[0049] In the present invention, when a reducing agent solution containing the aforementioned reducing agent is applied to a titanium dioxide coating layer and then heated in a preset atmosphere, the titanium dioxide coating layer is synthesized into a black titanium dioxide coating layer. Here, the preset atmosphere may be an environment of about 400°C to 800°C in a nitrogen atmosphere.

[0050] Next, a metal compound solution is applied to the black titanium dioxide coating layer (S300).

[0051] A metal compound is a compound containing a metal for increasing the generation rate of hydroxyl radicals of a photocatalyst, and may be a gold compound, a silver compound, a platinum compound, etc. In the present invention, it is assumed that a gold compound is used for convenience, but it is not limited thereto.

[0052] The gold compound may be chloroauric acid (HAuCl4), gold trioxide (Au2O3), or gold nitrate (HAu(No3)4), and there is no limitation on any gold compound that can deposit gold on the photocatalytic coating plate.

[0053] A metal compound solution is a solution in which a metal compound is dissolved in distilled water.

[0054] Additionally, when the metal compound solution is a chloroauric acid solution, the molar concentration is preferably 25 to 35 mM.

[0055] This is because when the molar concentration of the chloroauric acid (HAuCl4) solution is lower than 25 mM, the deposition rate of gold deposited on the photocatalyst decreases, and when the molar concentration of the chloroauric acid (HAuCl4) solution is higher than 35 mM, gold is not deposited uniformly.

[0056] Next, the gold compound in the metal compound solution is dried to concentrate it (S400).

[0057] At this time, drying is carried out until all of the distilled water in the metal compound solution is dried, and for example, the metal compound solution can be naturally dried for 15 to 25 minutes.

[0058] Next, the porous plate containing the metal compound is immersed in an alcohol solution (S500).

[0059] Here, the reason for immersing in an alcohol solution is to increase the deposition rate of the metal compound during photodeposition.

[0060] An alcohol solution is a solution that mixes alcohol and distilled water. The alcohol can be ethanol (C2H5OH), methanol (CH3OH), or isopropyl alcohol (C3H7OH), and more specifically, ethanol (C2H5OH) is preferred. When a dried plate is immersed in an ethanol (C2H5OH) solution among alcohol solutions to deposit gold, the highest gold deposition rate can be secured.

[0061] The ethanol (C2H5OH) solution can be prepared by mixing ethanol (C2H5OH) and distilled water at a preset volume ratio. Here, the preset volume ratio can be 0.5 to 1.5 : 8.5 to 9.5 based on ethanol (C2H5OH) and distilled water. The reason is that when the ratio of ethanol (C2H5OH) is higher than 15%, the gold deposition rate decreases. This is because the movement of gold compounds that are decomposed into ions by ultraviolet rays is not smooth in the ethanol (C2H5OH) solution. On the other hand, when the ratio of ethanol (C2H5OH) is lower than 5%, the decomposition of gold compounds into ions does not proceed smoothly.

[0062] Next, light is irradiated onto the porous plate to cause gold to be deposited on the black titanium dioxide (S600).

[0063] The light irradiated on the plate immersed in the alcohol solution has an ultraviolet wavelength range, and the irradiated light causes the chloroauric acid in the solution to decompose into gold ions, hydrogen ions, and chloride ions. The gold ions are then deposited on the plate coated with black titanium dioxide.

[0064] Here, when irradiated with ultraviolet rays of 300 nm to 400 nm wavelength, the electrons of gold move to the coated black titanium dioxide, and change O2 to O on the surface of black titanium dioxide. 2- It is reduced to . At this time, the reduced O 2- reacts with water molecules in the atmosphere to generate hydroxyl radicals. That is, O reduced by gold deposited on a titanium dioxide coated plate 2-The production of O increases and the amount of reduced O 2- The increased production of causes an increase in the amount of hydroxyl radicals produced, thereby improving the sterilizing power.

[0065] Although each process is described as being executed sequentially in FIG. 1, this is merely an illustrative description of the technical idea of ​​one embodiment of the present invention. In other words, a person of ordinary skill in the art to which one embodiment of the present invention pertains may modify and apply various modifications and variations, such as changing the order described in each drawing and executing the process, or executing one or more of the processes in parallel, without departing from the essential characteristics of one embodiment of the present invention. Therefore, FIG. 1 is not limited to a chronological order.

[0066] Meanwhile, the processes illustrated in FIG. 1 can be implemented as computer-readable code on a computer-readable recording medium. A computer-readable recording medium includes all types of recording devices that store data that can be read by a computer system. That is, a computer-readable recording medium includes storage media such as magnetic storage media (e.g., ROM, floppy disks, hard disks, etc.) and optical readable media (e.g., CD-ROMs, DVDs, etc.). In addition, a computer-readable recording medium can be distributed across network-connected computer systems, so that the computer-readable code can be stored and executed in a distributed manner.

[0067] The above description is merely an example of the technical idea of ​​the present embodiment, and those skilled in the art will appreciate that various modifications and variations can be made without departing from the essential characteristics of the present embodiment. Therefore, the present embodiments are not intended to limit the technical idea of ​​the present embodiment, but rather to explain it, and the scope of the technical idea of ​​the present embodiment is not limited by these embodiments. The scope of protection of the present embodiment should be interpreted by the claims below, and all technical ideas within a scope equivalent thereto should be interpreted as being included in the scope of rights of the present embodiment.

[0068]

[0069] CROSS-REFERENCE TO RELATED APPLICATION

[0070] This patent application claims priority under 35 USC § 119(a) to Korean Patent Application No. 10-2024-0010803, filed in Korea on January 24, 2024, the entire contents of which are incorporated by reference herein. Furthermore, this patent application claims priority in countries other than the United States for the same reasons, the entire contents of which are incorporated by reference herein.

Claims

1. A coating process in which a titanium dioxide (TiO2) solution is applied to a porous plate to coat it; A synthesis process in which a reducing agent solution for oxygen deficiency is applied to a porous plate coated with a titanium dioxide solution, and then heated to synthesize a titanium dioxide coating layer into a black titanium dioxide coating layer; A coating process of applying a metal compound solution to a porous plate having a black titanium dioxide coating layer formed thereon; and A deposition process in which light is irradiated onto a porous plate coated with a metal compound solution to cause the metal to be deposited on black titanium dioxide. A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that it includes:

2. In paragraph 1, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that it further includes a concentration process for concentrating the metal compound solution through drying for a preset time after the above-mentioned coating process.

3. In paragraph 2, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that it further includes an immersion process of immersing a porous plate in an alcohol solution after concentrating the above metal compound solution.

4. In paragraph 3, The above alcohol solution is an ethanol (C2H5OH) solution, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that the above ethanol solution is a mixture of ethanol and distilled water in a volume ratio of 0.5 to 1.5: 8.5 to 9.

5.

5. In paragraph 1, The above metal compound is chloroauric acid (HAuCl4), a gold compound, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that the above metal compound solution is a solution in which the above chloroauric acid (HAuCl4) is dissolved in distilled water.

6. In paragraph 5, The molar concentration of the above chloride gold solution is, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter characterized by having a particle size of 25 to 35 mM.

7. In paragraph 1, A method for manufacturing a black titanium dioxide photocatalytic sterilizing filter, characterized in that the light is ultraviolet rays and has a wavelength of 300 to 400 nm.

8. A black titanium dioxide photocatalytic sterilizing filter manufactured by any one of the manufacturing methods of clauses 1 to 7.

9. In paragraph 8, The above black titanium dioxide photocatalytic sterilizing filter, A black titanium dioxide photocatalytic sterilizing filter characterized in that it is activated at ultraviolet and visible light wavelengths of 200 nm to 800 nm and performs a sterilizing action.

10. An air purifier comprising a black titanium dioxide photocatalytic sterilizing filter of Article 8.

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