TWI433895B - Super hydrophilic hybrid titania photocatalyst and its application methods without light irradiation or with insufficient light irradiation condition - Google Patents

Description

Composite titanium dioxide photocatalyst sol coating composition having good hydrophilic property under no light irradiation or insufficient light irradiation and coating method thereof

The invention discloses a composite titanium dioxide photocatalyst sol coating composition and a coating method thereof, in particular to a composite titanium dioxide photocatalyst coating with a suitable coating technique to form a coating on the surface of the substrate, the coating is not exposed to light or light. It has good hydrophilic properties under sufficient irradiation, and can achieve the purpose of easy cleaning and anti-dirty. The technical scheme adopted by the invention is: a composite titanium dioxide photocatalyst sol coating composed of a titanium dioxide photocatalyst sol and a hydroxyl metal-containing porous metal oxide sol mixture, and the coating is applied to the surface of the substrate, characterized in that: The main body of the material is coated with a composite titanium dioxide photocatalyst sol coating on the surface of the substrate by a certain coating method, and the coating is dried and solidified. The surface of the composite titanium dioxide photocatalyst substrate is good under no light or insufficient light. Hydrophilic properties. The above substrates are glass, ceramic tile, stone, metal, acrylic plastic, polycarbonate plastic, polystyrene plastic, ABS plastic, tetrafluoroethylene, baking varnish, twin, metal oxide, copper indium gallium selenide coating. , textiles, ceramics, wood, bamboo, non-woven fabrics. The above coating methods are a roll coating method, a rub coating method, a brush coating method, a dip coating method, a spray coating method, a spin coating method, and a shower coating method. The above composite titanium dioxide photocatalyst coating material is composed of a titanium dioxide photocatalyst sol and a hydroxyl group-containing porous metal oxide sol in a certain ratio. The drying and curing conditions of the coating are dry curing at room temperature or heat drying, and the drying and curing temperature is 1000 ° C or lower.

Conventional titanium dioxide photocatalysts have photocatalytic efficacy under sunlight. By photocatalytic reaction of titanium dioxide photocatalyst irradiated by ultraviolet light, the organic pollutant molecules such as oil stains attached to the surface can be directly decomposed, or the macromolecular pollutants can be cleaved into small molecules to make the adhesion of the contaminant and the surface of the substrate. It weakens and is easily taken away by rain or washed away by water; in addition, the surface of the substrate coated with titanium dioxide photocatalyst film has good hydrophilic properties after being exposed to sunlight for a suitable time, so that water easily enters the gap between the contaminant and the substrate. Among them, the pollutants on the surface of the substrate are more easily taken away by the rain or washed away by the water. Therefore, titanium dioxide photocatalyst is widely used in various types of building materials as an antifouling coating. The crystal structure of titanium dioxide is a tetragonal high-temperature rutile type, a low-temperature anatase type, and an orthorhombic brookite type. Among them, only anatase structure has the effect of photocatalyst. The photodegradation mechanism of the photocatalytic treatment process is to activate the catalyst by ultraviolet light or sunlight, so that the catalyst generates electrons and holes, thereby oxidizing the substances adsorbed on the surface, thereby cracking the substances adsorbed on the surface into small molecules. Taking titanium dioxide as an example, the titanium dioxide reaction starts from a wavelength of 400 nm (because the energy difference of titanium dioxide is about 3.1 eV, and the wavelength of light at 400 nm provides about 3.1 eV), and the titanium dioxide absorbs light energy to generate electrons (e- And the hole (h+), which has a relatively strong oxidizing power, can directly oxidize the pollutant molecules adsorbed on the surface to decompose, or oxidize water molecules adsorbed on the surface into hydroxyl radicals ( OH). The pollutants of the original macromolecules cleave the macromolecules into small molecules through the photocatalytic photolysis reaction to achieve the purpose of decomposition or degradation of the pollutants.

Photocatalysts have been extensively studied for decades and are increasingly used in environmental protection, energy, sterilization, and self-cleaning. Since 1972, Fujishma and Honda published in Nature for the first time in the journal Nature that TiO ₂ will decompose water to produce H ₂ and O ₂ after illuminating. More and more people are investing in research on the photocatalytic properties of TiO ₂ and are committed to various possibilities. Modification method to improve the effect of TiO ₂ photocatalyst.

The existing domestic patents still focus on the preparation method of titanium dioxide and related applications, and there is no patent for the porous metal oxide upgrading method used in this case. The relevant domestic patents are listed in Table 1. Foreign related patents are listed in Table 2. In the published patent, there is no method for preparing a composite titanium dioxide photocatalyst using a porous metal oxide upgrading method as disclosed in the present invention.

Titanium dioxide photocatalyst itself needs sufficient light to achieve good hydrophilicity to achieve effective self-cleaning function, but in many cases, sufficient light can not be achieved. Without sufficient light, titanium dioxide photocatalyst will not perform well. The hydrophilicity, therefore, how to improve the hydrophilicity of the photocatalyst in the absence of light or insufficient light is the focus of the present invention.

The object of the present invention is to improve the hydrophilic property of the titanium dioxide photocatalyst in the absence of light irradiation or insufficient light irradiation, and apply a coating formed by disposing a titanium dioxide photocatalyst sol or a hydroxyl group-containing porous metal oxide sol in an appropriate ratio. The surface of the material forms a layer on the surface of the substrate after drying and curing A functional coating with good hydrophilic properties and photocatalytic properties. Under sufficient light conditions, the coating has the chemical decomposition or degradation characteristics of the titanium dioxide photocatalyst, which can decompose or degrade the organic contaminants attached to the surface of the substrate, and also has physical hydrophilic and decontaminating properties. When the coating is irradiated with no light or insufficient light, it has good hydrophilic properties, so that the substrate can be easily washed away by washing with water to maintain the cleanliness of the substrate.

The technical scheme adopted by the invention is: a composite titanium dioxide photocatalyst sol coating composed of a titanium dioxide photocatalyst sol and a hydroxyl metal-containing porous metal oxide sol mixture, and the coating is applied to the surface of the substrate, characterized in that: The main body of the material is coated with a composite titanium dioxide photocatalyst sol coating on the surface of the substrate by a certain coating method, and the surface of the composite titanium dioxide photocatalyst substrate can be expressed in the absence of light or insufficient light. Good hydrophilic properties.

The above composite titanium dioxide photocatalyst coating has good self-cleaning performance, and its performance verification is based on the water contact angle measurement method established by the Republic of China National Standard CNS 15378-1 or the international standard ISO 27448.

The above substrates are glass, ceramic tile, stone, metal, acrylic plastic, polycarbonate plastic, polystyrene plastic, ABS plastic, tetrafluoroethylene, baking varnish, twin, metal oxide, copper indium gallium selenide film, Textiles, ceramics, wood, bamboo, non-woven fabrics.

The above coating methods are a roll coating method, a rub coating method, a brush coating method, a dip coating method, a spray coating method, a spin coating method, and a shower coating method.

The above composite titanium dioxide photocatalyst coating is composed of titanium dioxide photocatalyst sol and hydroxyl-containing porous metal oxide sol in a certain proportion, wherein the titanium dioxide photocatalyst sol concentration is 0.01 g/liter to 100 g/liter, and the hydroxyl group-containing porosity The metal oxide sol concentration is from 0.01 g/L to 150 g/L.

The hydroxyl group-containing porous metal oxide sol is a porous cerium oxide sol, a porous alumina sol, a porous zinc oxide sol, a porous tungsten oxide sol, a porous tin oxide sol, a porous zirconia sol, and a porous A bismuth trioxide sol.

The drying and curing conditions of the coating layer may be dry curing at room temperature or heat drying, and the drying and curing temperature is 1000 ° C or lower.

The beneficial effects of the invention are:

1. The composite titanium dioxide photocatalyst coating of the present invention has good hydrophilic properties in the absence of light irradiation or insufficient light irradiation.

2. The composite titanium dioxide photocatalyst coating of the invention has the self-cleaning and easy-cleaning performance, and the good hydrophilic property greatly reduces the amount of water, and can realize the benefits of energy saving and carbon reduction.

3. The composite titanium dioxide photocatalyst coating of the invention has the advantages of easy cleaning, and the surface cleaning of the substrate can achieve a good cleaning effect, reduce the environmental pollution caused by the use of the cleaning agent, and conform to the model of green environmental protection.

4. The composite titanium dioxide photocatalyst coating of the invention has superior hydrophilicity, and can solve the problem that the silicone rubber joint material commonly used for building materials will seep out the oil after being exposed to sunlight, and pollute the surface of the building material to cause serious pollution and hardly clean. The composite titanium dioxide photocatalyst coating of the present invention can easily remove surface-contaminated eucalyptus oil with water and a brushing tool.

The embodiments described below are not limited to the description, and the composite titanium dioxide photocatalyst coatings are all within the scope of the present invention without departing from the spirit of the invention.

The technical scheme adopted by the invention is: a composite titanium dioxide photocatalyst sol coating composed of a titanium dioxide photocatalyst sol and a hydroxyl metal-containing porous metal oxide sol mixture, wherein the concentration of the titanium dioxide photocatalyst sol is 0.01 g/liter to 100 g/liter, The hydroxyl group-containing porous metal oxide sol has a concentration of 0.01 g/liter to 150 g/liter. Applying the coating to the surface of the substrate, characterized in that: a substrate body is coated on the surface of the substrate by a coating method using a composite titanium dioxide photocatalyst sol coating, and the formed coating is dried and solidified. It exhibits good hydrophilic properties without light or insufficient light. The above substrate is made of glass, ceramic tile, stone, metal, acrylic plastic, polycarbonate plastic, polystyrene plastic, ABS plastic, tetrafluoroethylene, baking varnish, twin, metal oxide, copper indium gallium selenide film. , textiles, ceramics, wood, bamboo, non-woven fabrics. The above coating methods are a roll coating method, a rub coating method, a brush coating method, a dip coating method, a spray coating method, a spin coating method, and a shower coating method. The above composite titanium dioxide photocatalyst coating material is composed of a titanium dioxide photocatalyst sol and a hydroxyl group-containing porous metal oxide sol in a certain ratio. The porous metal oxide sol described above is a porous cerium oxide sol, a porous alumina sol, a porous zinc oxide sol, a porous tungsten oxide sol, a porous tin oxide sol, a porous zirconia sol, Porous antimony trioxide sol. The drying and curing conditions of the coating layer may be dry curing at room temperature or heat drying, and the drying and curing temperature is 1000 ° C or lower. The coating method to be applied is a roll coating method, a wiping method, a brush coating method, a dip coating method, a spray coating method, a spin coating method, or a shower coating method. The composite titanium dioxide photocatalyst coating is evenly coated on the surface of the glass substrate to form a composite titanium dioxide photocatalyst coating on the surface of the substrate. The specific processing technology is as follows: the surface of the substrate is cleaned, and the coating is applied by roll coating, wiping or brushing. The method, the dip coating method, the spray coating method, the spin coating method and the shower coating method uniformly apply the composite titanium dioxide photocatalyst coating on the surface of the substrate, and after drying and curing the procedure, a coating layer is formed on the surface of the substrate. Comparing the hydrophilicity of the surface of the uncoated glass substrate with the surface of the glass substrate coated with the composite titanium dioxide photocatalyst coating, the water contact angle of the original glass surface is 38°-48°, and the surface of the composite titanium dioxide photocatalyst substrate is without light. The water contact angle is 4°-20°, and the water contact angle is 3°-15° when there is sufficient illumination, indicating that the surface of the composite titanium dioxide photocatalyst glass has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst coating of the invention has good coating. Hydrophilic efficacy. At the same time, the surface of the composite titanium dioxide photocatalyst glass has good self-cleaning performance, and the verification of its performance is based on the water contact angle measurement method established by the National Standard of China Republic of China CNS 15378-1 or the international standard ISO 27448, and the test piece is irradiated with ultraviolet rays. The critical contact angle of 96 hours is less than 25°, indicating that the surface of the composite titanium dioxide photocatalyst glass has good self-cleaning performance.

Example 1.

Referring to Figure 1, the substrate used is glass, which is sprayed and compounded. Titanium dioxide photocatalyst coating containing titanium dioxide photocatalyst sol concentration of 30 g / liter, hydroxyl-containing porous cerium oxide sol concentration of 20 g / liter, uniformly coated on the surface of the glass substrate, forming a composite titanium dioxide photocatalyst coating on the surface of the substrate The specific processing technology of the layer is:

1. The surface of the glass is cleaned, and the composite titanium dioxide photocatalyst coating is uniformly applied to the surface of the glass (10) by spraying, and after the coating is naturally dried, a coating (11) is formed on the surface of the glass;

2. Comparing the hydrophilicity of the uncoated glass with the surface of the glass coated with the composite titanium dioxide photocatalyst coating, the water contact angle of the original glass surface is 45.3°, and the water contact angle of the composite titanium dioxide photocatalyst glass in the absence of light is 4.2°. The water contact angle is 3.6° when there is sufficient illumination, which indicates that the surface of the composite titanium dioxide photocatalyst glass has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst sol coating coating of the invention has good hydrophilic antifouling performance.

3. Compare the surface of composite titanium dioxide photocatalyst glass test piece with oleic acid. The initial contact angle before UV irradiation is 65.5°, and the critical contact angle is 8.3° after UV irradiation for 48 hours, indicating that the surface of the composite titanium dioxide photocatalyst glass is good. Self-cleaning performance.

Example 2.

In the same manner as in the first embodiment, the composite titanium dioxide photocatalyst coating composition has a titanium dioxide photocatalyst sol concentration of 40 g/liter, a hydroxyl group-containing porous tungsten oxide sol concentration of 50 g/liter, and a coating processing method by a roll coating method. The material is a ceramic tile, and the ceramic tile is sintered in a heating furnace at 900 ° C to form a coating, which is specific The processing technology is:

1. Clean the surface of the tile, uniformly apply the composite titanium dioxide photocatalyst coating to the surface of the ceramic tile (10) by roller coating. After the coating is naturally dried, the tile is placed in a heating furnace at 900 ° C for 3 minutes, and the temperature is naturally lowered to the chamber. Warm, that is, forming a coating (11) on the surface of the tile;

2. Comparing the hydrophilicity of the uncoated ceramic tile with the surface of the tile coated by the composite titanium dioxide photocatalyst coating, the water contact angle of the original tile surface is 39.7°, and the water contact angle of the composite titanium dioxide photocatalyst tile in the absence of light is 6.2°. The water contact angle is 4.1° when there is sufficient illumination, which means that the surface of the composite titanium dioxide photocatalyst tile has good hydrophilicity and the photocatalytic performance can be maintained when the coating cures over 700 ° C. It proves that the composite titanium dioxide photocatalyst sol coating coating of the invention has Good hydrophilic and stain resistant performance.

3. Compare the surface of the composite titanium dioxide photocatalyst tile test piece with oleic acid. The initial contact angle before the ultraviolet irradiation is 65.7°, and the critical contact angle is 7.4° after 48 hours of UV irradiation, indicating that the composite titanium dioxide photocatalyst tile surface has good surface. Self-cleaning performance.

Example 3.

In the same manner as in the first embodiment, the composite titanium dioxide photocatalyst coating composition has a titania-containing photocatalyst sol concentration of 50 g/liter, a hydroxyl group-containing porous alumina sol concentration of 70 g/liter, and a coating processing method by brush coating method. The material is smooth stone, and the stone is dried in a hot air of 100 ° C to form a coating. The specific processing technology is as follows:

1. Clean the surface of the stone, apply the composite titanium dioxide photocatalyst coating to the surface of the stone (10) evenly by brushing. After the coating is naturally dried, the stone is cured in a hot air of 100 ° C for 30 minutes, and naturally cooled to room temperature. , that is, forming a coating on the surface of the stone (11);

2. Comparing the hydrophilicity of the uncoated stone with the surface of the stone coated with the composite titanium dioxide photocatalyst coating, the water contact angle of the original stone surface is 41.8°, and the water contact angle of the composite titanium dioxide photocatalyst stone in the absence of light is 6.2°. The water contact angle is 3.1° when there is sufficient illumination, which indicates that the surface of the composite titanium dioxide photocatalyst stone has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst sol coating coating of the invention has good hydrophilic antifouling performance.

3. Compare the surface of composite titanium dioxide photocatalyst stone test piece with oleic acid. The initial contact angle before UV irradiation is 58.6°, and the critical contact angle is 6.3° after 36 hours of UV irradiation, indicating that the composite titanium dioxide photocatalyst stone surface has good surface. Self-cleaning performance.

Example 4.

In the same manner as in the first embodiment, the composite titanium dioxide photocatalyst coating composition has a titanium dioxide photocatalyst sol concentration of 80 g/liter, a hydroxyl group-containing porous zinc oxide sol concentration of 120 g/liter, and a coating processing method by a wiping method. The material is a stainless steel plate, and the stainless steel plate is dried in a hot air of 250 ° C to form a coating. The specific processing technology is as follows:

1. Clean the surface of the stainless steel plate and combine the composite titanium dioxide photocatalyst coating The coating was uniformly applied to the surface of the stainless steel plate (10) by a wiping method, and the coating was naturally air-dried, and then the stainless steel plate was cured in a hot air of 250 ° C for 20 minutes, and naturally cooled to room temperature, that is, a coating was formed on the surface of the stainless steel plate ( 11);

2. Comparing the hydrophilicity of the uncoated stainless steel plate with the surface of the stainless steel plate coated with the composite titanium dioxide photocatalyst coating, the water contact angle of the original stainless steel plate surface is 48.5°, and the water contact angle of the composite titanium dioxide photocatalytic stainless steel plate in the absence of light When it is 8.2°, the water contact angle is 5.8° when there is sufficient illumination, which indicates that the surface of the composite titanium dioxide photocatalyst stainless steel plate has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst sol coating coating of the invention has good hydrophilic antifouling performance.

3. Compare the surface of the composite titanium dioxide photocatalyst stainless steel plate with oleic acid. The initial contact angle before the ultraviolet irradiation is 66.4°, and the critical contact angle is 7.8° after 24 hours of violet light irradiation, indicating that the composite titanium dioxide photocatalyst stainless steel plate The surface has good self-cleaning properties.

Example 5.

In the same manner as in the first embodiment, the composite titanium dioxide photocatalyst coating composition has a titania-containing photocatalyst sol concentration of 100 g/liter, a hydroxyl group-containing porous tin oxide sol concentration of 150 g/liter, and a coating processing method by dip coating method. The material is a polycarbonate plastic plate, and the polycarbonate plastic plate is dried in a hot air of 50 ° C to form a coating. The specific processing technology is as follows:

1. Clean the surface of the polycarbonate plastic plate and apply the composite titanium dioxide photocatalyst coating to the surface of the plastic plate (10) by dip coating. The coating is natural. After air drying, the plastic plate is cured in a hot air of 50 ° C for 120 minutes, and naturally cooled to room temperature, that is, a coating (11) is formed on the surface of the plastic plate;

2. Comparing the hydrophilicity of the surface of the polycarbonate plastic sheet coated with the uncoated polycarbonate plastic sheet and the composite titanium dioxide photocatalyst coating, the water contact angle of the surface of the original polycarbonate plastic board is 64.2°, and the composite titanium dioxide photocatalyst is polymerized. The water contact angle of the carbonate plastic plate is 8.3° when there is no light, and the water contact angle is 6.2° when there is sufficient illumination, indicating that the surface of the composite titanium dioxide photocatalyst polycarbonate plastic plate has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst of the present invention proves The sol coating has good hydrophilic and antifouling properties.

3. Compare the surface of the composite titanium dioxide photocatalyst polycarbonate plastic plate with oleic acid. The initial contact angle before the ultraviolet irradiation is 74.8°, and the critical contact angle after the 24-hour UV irradiation is 8.1°, indicating the composite titanium dioxide photocatalyst. Polycarbonate plastic panels have good self-cleaning properties.

Example 6.

In the same manner as in the first embodiment, the composite titanium dioxide photocatalyst coating composition has a titania-containing photocatalyst sol concentration of 60 g/liter, a hydroxyl group-containing porous zirconia sol concentration of 100 g/liter, and a coating processing method by a shower coating method. The material is an aluminum plate, and the aluminum plate is dried in a hot air of 150 ° C to form a coating. The specific processing process is as follows:

1. Clean the surface of the aluminum plate and pour the composite titanium dioxide photocatalyst coating The coating method is evenly coated on the surface of the aluminum plate (10), the coating is naturally air-dried, and the aluminum plate is cured in a hot air at 150 ° C for 60 minutes, and naturally cooled to room temperature, that is, a coating (11) is formed on the surface of the aluminum plate;

2. Comparing the hydrophilicity of the uncoated aluminum plate with the surface of the aluminum plate coated with the composite titanium dioxide photocatalyst coating, the water contact angle of the original aluminum plate surface is 46.1°, and the water contact angle of the composite titanium dioxide photocatalytic aluminum plate in the absence of light is 7.2°. The water contact angle is 5.4° when there is sufficient illumination, which indicates that the surface of the composite titanium dioxide photocatalyst aluminum plate has good hydrophilicity, which proves that the composite titanium dioxide photocatalyst sol coating coating of the invention has good hydrophilic antifouling performance.

3. Comparing the surface of the composite titanium dioxide photocatalytic aluminum plate test piece with oleic acid, the initial contact angle before the ultraviolet irradiation is 64.8°, and the critical contact angle after the 36 hours of violet light irradiation is less than 7.4°, indicating that the composite titanium dioxide photocatalytic aluminum plate has good. Self-cleaning performance.

10‧‧‧Substrate

11‧‧‧Composite titanium dioxide photocatalyst coating

Figure 1 is a structural view of a composite titanium dioxide photocatalyst substrate.

10‧‧‧Substrate

11‧‧‧Composite titanium dioxide photocatalyst coating

Claims (17)

A composite titanium dioxide photocatalyst sol coating composition having good hydrophilic properties under no light irradiation or insufficient light irradiation, characterized in that the composite titanium dioxide photocatalyst sol coating is composed of a titanium dioxide photocatalyst sol and a porous selected from a hydroxyl group. Oxidized cerium oxide sol, hydroxyl-containing porous tungsten oxide sol, hydroxyl-containing porous alumina sol, hydroxyl-containing porous zinc oxide sol, hydroxyl-containing porous tin oxide sol, One or more of the hydroxyl group-containing porous metal oxide sols of the group consisting of a porous zirconia sol of a hydroxyl group, and a coating composition formed in an appropriate ratio, wherein the solid content of the titanium dioxide photocatalyst sol is 0.01克 / 升 ~ 100 g / liter, the hydroxyl-containing porous metal oxide sol solid content of 0.01 g / liter ~ 150 g / liter, the composite titanium dioxide photocatalyst sol coating coated on the substrate has no light or Good hydrophilic properties when exposed to insufficient light. The composition of claim 1, wherein the titanium dioxide photocatalyst sol has a solid content of 0.1 to 50 g/liter. The composite titanium dioxide photocatalyst sol coating composition according to claim 2, wherein the titanium dioxide photocatalyst sol has a solid content of 1 to 30 g/liter. The composition of claim 1, wherein the hydroxyl-containing porous metal oxide sol has a solid content of 0.1 to 100 g/liter. The composition of claim 4, wherein the hydroxyl-containing porous metal oxide sol has a solid content of from 1 to 50 g/liter. The composite titanium dioxide photocatalyst sol coating composition according to any one of claims 1 to 5, which is applied to a substrate, and the coating formed on the substrate is subjected to a drying curing process in the absence of light or light. It exhibits good hydrophilic properties under insufficient irradiation. For example, the compound titanium dioxide photocatalyst sol coating composition of claim 6 is made of glass, ceramic tile, stone, metal, acrylic plastic, polycarbonate plastic, polystyrene plastic, ABS plastic, PTFE. Ethylene, lacquered board, textiles, ceramics, wood, bamboo, non-woven fabrics. A composite titanium dioxide photocatalyst sol coating composition according to claim 6 wherein the light source is a daylight or an artificial light source. For example, the composite titanium dioxide photocatalyst sol coating composition of claim 6 has good self-cleaning performance under a certain light irradiation. A substrate coating processing application method for a composite titanium dioxide photocatalyst sol coating composition, comprising the following steps and features: (i) a composite titanium dioxide photocatalyst sol coating, which is a composite titanium dioxide photocatalyst sol according to any one of claims 1 to 9. The coating composition is uniformly stirred and uniformly mixed and filtered to obtain a composite titanium dioxide photocatalyst sol coating; and (ii) the surface coating of the substrate is prepared by uniformly coating the composite titanium dioxide photocatalyst sol coating on the surface of the substrate by a certain coating method to form a layer. The coating maintains the uniformity of the appearance of the coating, and the coating is cured so that the coating adheres more firmly to the surface of the substrate, and a functional coating is formed after the drying and curing process. The method for coating and processing a substrate of a composite titanium dioxide photocatalyst sol coating composition according to claim 10, wherein the coating method is a roll coating method, a wiping method, a brush coating method, a pulling method, a spraying method, and a spin coating method. , dripping method. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition of claim 10, wherein the curing condition of the coating is cured at room temperature. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition according to claim 10, wherein the curing condition of the coating is cured at a temperature of 1000 ° C or lower. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition of claim 10, wherein the curing condition of the coating can maintain good photocatalytic performance when the temperature is above 700 ° C. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition according to claim 10, wherein the substrate is made of glass, ceramic tile, stone, metal, acrylic plastic, polycarbonate plastic, polystyrene. Plastic, ABS plastic, tetrafluoroethylene, baking varnish, textiles, ceramics, wood, bamboo, non-woven fabrics. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition of claim 10, the coating has good self-cleaning performance under light irradiation. The substrate coating processing application method of the composite titanium dioxide photocatalyst sol coating composition of claim 16 wherein the light source is a daylight or an artificial light source.