KR102152874B1 - Soundproofing pannel comprising visible light active photocatalyst - Google Patents

Abstract

The present invention relates to a soundproof panel including a visible light active photocatalyst. According to one aspect of the present invention, the soundproof panel including the visible light active photocatalyst includes: a basic material; and a coating layer including the photocatalyst formed on at least a part of a surface of the basic material, wherein the photocatalyst includes an inorganic oxide and a metal oxide layer derived from an organic metal compound formed on the inorganic oxide and has the photoactivity in a visible light region of 400 nm or more.

Description

Soundproof panel containing a visible light active photocatalyst {SOUNDPROOFING PANNEL COMPRISING VISIBLE LIGHT ACTIVE PHOTOCATALYST}

The present invention relates to a soundproof panel, and more specifically, to a soundproof panel introduced into a soundproof wall usable in places such as roads, railway tracks, and factories with high noise.

In general, soundproof walls are formed by connection of soundproof panels, and were introduced as a means to separate a noisy space from other areas.

As a representative example, soundproof walls are installed around roads to physically separate roads and residential complexes, and block various noises generated from vehicles passing through roads. At this time, most of the soundproof walls were made of concrete or reinforced structures.

The soundproof wall is also formed in a structure that accommodates materials such as sound-absorbing materials therein, and various structures are introduced and designed for the convenience of transportation or construction.

Furthermore, in recent years, in addition to the inherent soundproofing function of the soundproofing wall, the soundproofing walls with the function of preventing environmental pollution have been developed to shield fine dust or exhaust gas components generated from roads from the surrounding space.

On the other hand, a photocatalyst has catalytic activity by absorbing light energy, and oxidizes and decomposes environmental pollutants such as organic substances with strong oxidizing power by catalytic activity. That is, the photocatalyst irradiates light (ultraviolet rays) having an energy of a band gap or higher to cause a transition of electrons from a valence band to a conduction band, and a hole is formed in the valence band. These electrons and holes diffuse to the surface of the powder, and cause a redox reaction or recombine to generate heat by contacting oxygen and moisture. That is, electrons in the conduction band reduce oxygen to produce superoxanions, and holes in the valence band oxidize moisture to form hydroxy radicals (OH·). Due to the strong oxidizing power of hydroxy radicals (OH·) generated by these holes, it is possible to decompose, sterilize, hydrophilicity, etc. of gaseous or liquid organic substances adsorbed on the surface of the photocatalyst, that is, hardly decomposable organic substances. In general, titanium dioxide (TiO ₂ ) powder is used as a photocatalyst, and titanium dioxide (TiO ₂ ) is harmless to the human body, has excellent photocatalytic activity, has excellent light corrosion resistance, and has an inexpensive price. Titanium dioxide (TiO ₂ ) absorbs and reacts with ultraviolet rays of 388 nm or less, thereby generating electrons (conduction band) and holes (valence band), and ultraviolet rays used as light sources are used as light sources such as lamps, incandescent lamps, and mercury lamps. Artificial lighting, light-emitting diodes, and the like can be used. The electrons and holes generated in the reaction recombine in 10 ^-12 to 10 ^-9 seconds, but if contaminants or the like adsorb to the surface before recombination, they are decomposed by the electrons and holes. However, the band gap energy (wavelength of 380 nm or more) of titanium dioxide (TiO ₂ ) powder is obtained from sunlight, and since about 2% of the light can be used, smooth catalytic activity in the visible region (400-800 nm), the main wavelength of sunlight. Have difficulty having In other words, in order to respond to visible light, it is essential to effectively reduce the band gap of the photocatalyst and efficiently separate the electron/hole pairs generated through light absorption. The efficiency in the visible light-sensitive photocatalyst of titanium dioxide (TiO ₂ ) powder has not yet been achieved. The situation was not reaching the level for commercialization in the air cleaning field.

The present invention is to solve all the demands for improvement of the above-described soundproof panel, air pollution in the modern society, and supplementation for insufficient functions of photocatalyst, and the present invention is formed by introducing a doping process of an organometallic compound. An inorganic oxide-based photocatalyst having excellent photocatalytic activity in the light ray region was developed and used for soundproof panels and soundproof walls with soundproof panels.

An embodiment of the present invention is applied in a manner of forming a coating layer on a part of a soundproof panel using a newly developed photocatalyst activated in visible light.

An embodiment of the present invention is to provide a soundproof panel including an inorganic oxide-based photocatalyst and having a function of purifying the surrounding air even when exposed to light by having a photolysis function. This technology is in line with the recent development trend of various facilities to reduce environmental pollution, and solves both the modern people's desire for air purification and the problems of photocatalysts that were difficult to commercialize.

According to an embodiment of the present invention, not only by manufacturing a structure using the soundproof panel of the present invention without a separate air purifier, but also a technology for removing harmful substances from the surrounding air To provide.

However, the problems to be solved by the present invention are not limited to those mentioned above, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

A soundproof panel comprising a visible light active photocatalyst according to an aspect of the present invention includes: a substrate; A coating layer including a photocatalyst formed on at least a portion of the surface of the substrate; the photocatalyst includes an inorganic oxide particle and a metal oxide layer derived from an organometallic compound formed on the inorganic oxide particle, and visible light of 400 nm or more It has photoactivity in the region, the specific surface area of the photocatalyst is 5 (m ² /g) or more, the average pore size is 50 nm or less, and the inorganic oxide includes at least one of Ti, Zn, Al, and Sn. It includes at least one selected from the group consisting of oxides, and the metal oxide layer contains iron oxide in an amount of 0.001 to 10% by weight relative to the inorganic oxide, and the photocatalyst exhibits photoactivity in dry conditions of 30% or less humidity. And the metal oxide layer contains ferrocene-derived iron oxide.

According to an embodiment, the coating layer may further include a polymer resin, a silicone resin, silica, and a water repellent fluororesin.

According to an embodiment, the coating layer may further include at least one metal material selected from the group consisting of silver, copper, zinc, and platinum group metal elements.

According to an embodiment, the substrate may include RB ceramics, CRB ceramics, or both.

According to an embodiment, the metal oxide layer may include ferrocene-derived iron oxide.

According to an embodiment, the inorganic oxide includes at least one selected from the group consisting of oxides containing at least one of Ti, Zn, Al, and Sn, and the metal oxide layer is 0.001 to 10 weights compared to the inorganic oxide. % Iron oxide, and the photocatalyst may have photoactivity under dry conditions of 30% or less humidity.

According to an embodiment, the photocatalyst may have photoactivity in a dry condition with a humidity of 30% or less.

According to an embodiment, the inorganic oxide does not contain an inorganic oxide containing iron, and the metal oxide layer may be obtained by heat treatment of ferrocene deposited on the inorganic oxide.

According to an embodiment, the metal oxide may include one or more of the compounds represented by Formula 1 below.

[Formula 1]

Me _x O _Y H _Z

(Me is one or more metal elements from Groups 1 to 3, X, Y, and Z are each selected from 0 to 3, and X and Y are not 0.)

According to an embodiment, the specific surface area of the photocatalyst may be 5 (m ² /g) or more, and the average pore size may be 50 nm or less.

The sound insulation wall comprising a visible light active photocatalyst according to another aspect of the present invention includes at least one sound insulation panel corresponding to an embodiment of the present invention, and the sound insulation panel is in a dry condition of 30% or less and a humidity of 400 nm or more. It includes a photocatalyst having photoactivity in the visible region.

According to an embodiment of the present invention, a soundproof panel including a photocatalytic coating layer is provided, and the soundproof panel has an effect of reducing harmful substances in the surrounding air by simply exposing it to visible light in addition to its natural function of blocking noise. I can reap.

More specifically, according to an embodiment of the present invention, an inorganic oxide-based photocatalyst having excellent photocatalytic activity in the visible light region and excellent photolysis efficiency in various humidity and temperature regions is prepared, and a soundproof panel to which such a photocatalyst is applied is provided. I can.

The soundproof panel proposed in the present invention includes a photocatalyst that is activated even in a visible light region and low humidity environmental conditions, and thus it is possible to purify the surrounding air in various exposure environments.

The soundproof panel including a visible light-activating photocatalyst proposed in the present invention may be one in which the photocatalyst is activated by receiving light including a visible light region. Through this, the soundproof panel proposed in the present invention alleviates fears of air pollution among modern people, and allows the surrounding air to be purified without the need to have a separate air purifier, so that various environments in which a structure for noise reduction can be applied. It can be applied universally.

The present invention can provide a soundproof panel including an inorganic oxide-based photocatalyst manufactured by a simple and economical method, and the soundproof panel with the inorganic oxide-based photocatalyst includes a photocatalyst that can be activated even under dry conditions. It has the ability to decompose volatile organic compounds with high efficiency and excellent stability in response to light in the visible region.

Specifically, the photocatalyst proposed in an embodiment of the present invention is not only a soundproof panel for manufacturing an outdoor soundproof wall, but also an indoor soundproof panel, an outer wall or an inner wall of a building, and an area where various shielding facilities are required. It does not exclude the possibility of being applied in combination.

1 is a flowchart illustrating a method of manufacturing a photocatalyst applied to the present invention according to an embodiment of the present invention.
2 is an exemplary diagram showing the configuration of a TR-CVD reactor used in a manufacturing process of a photocatalyst applied to the present invention according to an embodiment of the present invention.
3 is an exemplary view showing a manufacturing process of a photocatalyst applied to the present invention according to an embodiment of the present invention.
4 shows an image of a photocatalyst applied to the present invention manufactured according to an embodiment of the present invention.
5 shows a TEM image of a photocatalyst prepared according to an embodiment of the present invention.
6 shows the evaluation results of the photolysis performance of the photocatalyst prepared according to the embodiment of the present invention.
7 shows an evaluation result of photolysis performance according to humidity of a photocatalyst prepared according to an embodiment of the present invention.
8 shows the stability evaluation results of photolysis performance according to repeated photolysis experiments of a photocatalyst prepared according to an embodiment of the present invention.
9 is a structural diagram schematically showing the structure of a sound insulation wall including a sound insulation panel including a photocatalyst manufactured according to an embodiment of the present invention.

Hereinafter, exemplary embodiments will be described in detail with reference to the accompanying drawings.

Various changes may be made to the embodiments described below. The embodiments described below are not intended to be limited to the embodiments, and should be understood to include all changes, equivalents, and substitutes thereto.

The terms used in the examples are used only to describe specific embodiments, and are not intended to limit the embodiments. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, terms such as "comprises" or "have" are intended to designate the presence of features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, but one or more other features. It is to be understood that the presence or addition of elements or numbers, steps, actions, components, parts, or combinations thereof, does not preclude in advance the possibility.

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 embodiment belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and should not be interpreted as an ideal or excessively formal meaning unless explicitly defined in this application. Does not.

In addition, in the description with reference to the accompanying drawings, the same reference numerals are assigned to the same components regardless of the reference numerals, and redundant descriptions thereof will be omitted. In describing the embodiments, when it is determined that a detailed description of related known technologies may unnecessarily obscure the subject matter of the embodiments, the detailed description thereof will be omitted.

In addition, terms used in the present specification are terms used to properly express a preferred embodiment of the present invention, which may vary depending on the intention of users or operators, or customs in the field to which the present invention belongs. Accordingly, definitions of these terms should be made based on the contents throughout the present specification. The same reference numerals in each drawing indicate the same members.

Throughout the specification, when a member is said to be positioned "on" another member, this includes not only the case where a member is in contact with another member, but also the case where another member exists between the two members.

Throughout the specification, when a part "includes" a certain component, it means that other components may be further included rather than excluding other components.

Hereinafter, a soundproof panel including a photocatalyst of the present invention will be described in detail with reference to examples and drawings. However, the present invention is not limited to these examples and drawings.

The present invention may relate to a soundproof panel capable of performing a function of purifying ambient air only by being installed and exposed to light by including photocatalytic particles in the coating layer of the soundproof panel. In addition, the photocatalyst applied to the soundproof panel of the present invention, unlike conventional photocatalysts, can be sufficiently activated even if the wavelength in the ultraviolet region is not irradiated and only exposed to light in the visible region. Therefore, only exposure to sunlight outdoors or indoors can purify the air in the surrounding space with high efficiency without a special driving device.

The present inventors have confirmed that this effect can be implemented through a photocatalyst including a metal oxide layer formed by heat-treating an organometallic compound, and developed a soundproof panel capable of maximizing the characteristics of such a photocatalyst, and proposed it. will be.

In the present invention, in addition to the sound absorption and sound shielding functions of a general soundproof panel, it is possible to expect a function of purifying the surrounding air.

The photocatalyst applied to an example of the present invention improves the problem of the conventional photocatalyst, which is difficult to commercialize because it is activated only in the ultraviolet region, and is sufficiently activated in the visible region of 400 nm or more. The photocatalyst applied to the present invention can exhibit its function even if it is installed in an indoor or outdoor environment capable of receiving sunlight.

The photocatalyst may include an inorganic oxide and a metal oxide layer formed thereon. In this case, the inorganic oxide and the metal oxide layer are referred to as a photocatalyst. The photocatalyst may be in the form of particles, but may not. Unlike conventional photocatalysts, the photocatalyst is characterized by having active photoactivity by reacting with a wavelength of 400 nm or more in the visible light region. This may be an effect implemented in a metal oxide layer derived from an organometallic compound.

The photocatalyst particles may be formed on the outer surface coating layer exposed to light of the soundproof panel.

A soundproof panel comprising a visible light active photocatalyst according to an aspect of the present invention includes: a substrate; A coating layer including a photocatalyst formed on at least a portion of the surface of the substrate, wherein the photocatalyst includes an inorganic oxide and a metal cargo layer derived from an organometallic compound formed on the inorganic oxide, and in a visible light region of 400 nm or more It has photoactivity.

The soundproof panel may be one or more of the panels for constructing a soundproof wall. In addition, the soundproofing wall may be a soundproofing wall installed at a height on the road, but is not limited thereto. The soundproof wall may be a soundproof wall installed in a railroad or a factory, or may be a soundproof wall installed to block indoor noise.

The sound insulation panel is not necessarily limited to being installed in the form of a sound insulation “wall”, and may be used to form a structure formed by an independent panel or a combination of panels.

It may be advantageous to use a material having a high hardness, a low coefficient of thermal expansion, and a low specific gravity as the substrate. In addition, the substrate may be a material having abrasion resistance, porosity, sound absorption, gas adsorption, and water absorption. As an example, the substrate may be formed in a structure including or inserting a sound-absorbing material therein.

The sound-absorbing material may include various components, as an example, may include at least one selected from the group consisting of lightweight aggregates, urethane foams, and glass wool, and may include a porous material and a plate-like material.

The substrate may include, for example, concrete and/or fly ash components.

As an example, the substrate may be a ceramic material that is easily manufactured through molding or mold, and it is preferable to use a material that is chemically stable in relation to the coating layer including the photocatalyst. The base material is not particularly limited as long as it is a material that has chemical stability against radicals generated when the photocatalyst acts.

The substrate is reinforced; Mineral enhancers; Metal foam materials; Metal fibers including glass wool and rock wool and aluminum; Ceramic sintered body; And inorganic foam material; may be to include one or more selected from the group consisting of.

The material is not particularly limited as long as it is a material in which a coating layer is formed on the outside and a sound-absorbing material can be introduced into the substrate, and the material is easily molded.

According to an embodiment, the coating layer may further include a polymer resin, a silicone resin, silica, and a water repellent fluororesin.

The coating layer may include both a hydrophobic resin and a hydrophilic resin. The coating layer may include a hydrophobic region derived from a hydrophobic resin and a hydrophilic region derived from a silicone resin or silica at the same time.

Since the hydrophobic region and the hydrophilic region coexist, both the hydrophilic substance and the hydrophobic substance cannot adhere to the surface of the coating layer, so that the surface of the coating layer is maintained to be clean.

According to an embodiment, the coating layer may further include at least one metal material selected from the group consisting of silver, copper, zinc, and platinum group metal elements.

The coating layer to which the metallic element is added can kill bacteria and molds adhering to the surface of the coating layer in a dark place. Therefore, when the metal element is included in the coating layer, antifouling properties can be further improved.

The coating layer may include one or more of platinum group metal elements such as Pt, Pd, Ru, Rh, Ir, and Os. The coating layer to which the platinum group metal element is added may enhance the redox activity of the photocatalyst, thereby improving decomposition of organic matter contamination and decomposition of harmful gases and odors.

According to an embodiment, the coating layer may form a thickness of 0.1 mm to 50 mm on the substrate. Preferably, the coating layer may be formed to a thickness of 0.5 mm to 2 mm on the substrate. If the thickness of the coating layer is too thin, it is difficult to implement a sufficient air purification effect of the photocatalyst, and if it is too thick, the cost increases and the air purification effect is saturated.

According to an embodiment, the coating layer may include RB ceramics, CRB ceramics, or both.

RB ceramics and CRB ceramics refer to a new concept of carbon-based ceramic materials manufactured using rice bran, which is emitted more than 33 million tons worldwide each year.

The RB ceramics and/or CRB ceramics may be a carbon material obtained by mixing and kneading degreasing bran obtained from rice bran and a thermosetting resin, drying the molded body under pressure molding, and then firing the dried molded body in an inert gas atmosphere. . At this time, the thermosetting resin may include a phenol resin, a diaryl phthalate resin, an unsaturated polyester resin, an epoxy resin, a polyimide resin, and a triazine resin.

The RB ceramics or CRB ceramics may be dehydrated at a temperature of 100 degrees or more after molding using a known manufacturing method of RB ceramics or CRB ceramics.

The RB ceramics and/or CRB ceramics impart high hardness, low coefficient of thermal expansion, low electrical conductivity, and high abrasion resistance to the coating layer of the soundproof panel, and are porous and can impart sound absorption, gas adsorption and absorption. At the same time, the RB ceramics and/or CRB ceramics are chemically stable and can impart non-problem characteristics even to strong radicals generated when the photocatalyst acts.

According to an embodiment, the metal oxide layer may include ferrocene-derived iron oxide.

According to an embodiment, the inorganic oxide includes at least one selected from the group consisting of oxides containing at least one of Ti, Zn, Al, and Sn, and the metal oxide layer is 0.001 to 10 weights compared to the inorganic oxide. % Iron oxide, and the photocatalyst may have photoactivity under dry conditions of 30% or less humidity.

According to an embodiment, the photocatalyst is an inorganic oxide; And a metal oxide layer formed on the inorganic oxide. It may include.

The inorganic oxide may include at least one selected from the group consisting of oxides containing at least one of Ti, Zn, Al, and Sn.

The metal oxide layer may include a ferrocene-derived iron oxide layer. In this case, the content of iron may be 0.001 to 10% by weight based on the inorganic oxide, and preferably 0.001 to 5% by weight based on the inorganic oxide.

The inorganic oxide is an inorganic semiconductor compound that absorbs light energy and exhibits catalytic activity. For example, Ti, Zn, Al, Fe, W, Sn, Bi, Ta, Cu, Si, Ru, Sr, Ba and Ce It is an oxide containing at least one selected from the group consisting of, and preferably may be Ti, Zn, Al, and Sn. Specifically, TiO ₂ , Al ₂ O ₃ , ZnO ₂ , ZnO, SrTiO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , NiO, Cu ₂ O, SiO, SiO ₂ , MoS ₂ , InPb, RuO ₂ , CeO _{2 and the} like. In addition, semiconductor compounds such as CdS, GaP, InP, GaAs, InPb, etc. may be further included in addition to oxides.

According to an embodiment, the inorganic oxide may include at least one selected from the group consisting of beads, powders, rods, wires, needles, and fibers, and the size of the inorganic oxide may range from 1 nm to 500 μm.

The inorganic oxide includes at least one selected from the group consisting of beads, powder, rod, wire, needle, and fiber, and the size of the inorganic oxide is 1 nm or more; 10 nm or more; 30 nm to 500 μm; 30 nm to 100 μm; Alternatively, it may be 30 nm to 1 μm. The size may mean diameter, thickness, length, etc. depending on the shape.

According to an embodiment, the inorganic oxide does not contain an inorganic oxide containing iron, and the metal oxide layer may be obtained by heat treatment of ferrocene deposited on the inorganic oxide.

As an example, the metal-organic compound-derived metal oxide layer may be formed by a ferrocene doping process. For example, the ferrocene layer formed on the inorganic oxide may be heat-treated to thermally decompose ferrocene, and iron oxide converted from ferrocene may be included by this pyrolysis process. The doping process of the organometallic compound will be described in more detail in the following manufacturing method.

The metal oxide layer derived from the organometallic oxide may be, for example, an iron oxide derived from at least one of ferrocene and ferrocene derivatives. The ferrocene derivatives include ferrocene aldehyde, ferrocene ketone, ferrocene carboxylic acid, ferrocene alcohol, phenol or ether compound, nitrogen-containing ferrocene compound, sulfur-containing ferrocene compound, phosphorus-containing ferrocene compound, silicon-containing ferrocene compound, 1,1' -In the group consisting of dicoper ferrocene (1,1'-di-copper ferrocene), ferrocene boric acid, ferrocenyl cuprous acetylide and bisferrocenyl titanocene It may include at least one selected.

As an example, the content of metal in the metal oxide layer derived from the organometallic compound is 0.001 to 10% by weight compared to the inorganic oxide; 0.01 to 10% by weight; 0.01 to 3% by weight; 0.01 to 1.5% by weight; Or it may be included in 0.01 to 1% by weight. If included within the above range, photocatalytic activity may be increased in a visible light region, thereby improving photolysis efficiency. In addition, when the content of metal is increased, absorption in the visible light region may increase, but since the photocatalytic activity may be deteriorated due to the increase in the metal content, it is preferable to include a metal content within the above range, and more preferably, the above The metal is iron, and the content of iron may be 0.01 to 5% by weight.

As an example, the metal oxide layer derived from the organometallic compound, 0.01 nm or more; 0.1 nm or more; 10 nm or more; Alternatively, it may have a thickness of 1 nm to 100 nm. When included within the above thickness range, it is possible to prevent a decrease in porosity of the photocatalyst due to an increase in the thickness of the coating layer, and increase the amount of adsorption of moisture, OH- ions, and decomposition targets on the surface, thereby improving photolysis performance. In addition, the metal oxide layer derived from the organometallic compound is 0.01 nm or more; 0.1 nm or more; 10 nm or more; Or it may include ferrocene-derived iron oxide having a size of 1 nm to 100 nm. The size may mean length, diameter, thickness, etc. depending on the shape.

According to an embodiment, the inorganic oxide does not contain an inorganic oxide containing iron, and the iron oxide layer may be obtained by heat treatment of ferrocene deposited on the inorganic oxide.

The metal oxide may include one or more of the compounds represented by Formula 1 below.

[Formula 1]

Me _x O _Y H _Z

Here, Me is one or more of metal elements corresponding to groups 1 to 3, X, Y and Z are each selected from 0 to 3, and X and Y are not 0.

As an example, the Z may also be non-zero.

As an example, iron oxide (Fe _x O _y H _z ), a semiconducting material that absorbs visible light and is stable and inexpensive, is introduced into the surface of TiO _{2 in the} form of nano-sized particles to create a photocatalyst that is sensitive to visible light. Can be formed.

According to an embodiment of the present invention, the photocatalyst may expand a wavelength region that absorbs light and exhibits a photoreaction from ultraviolet rays to visible rays. The photocatalyst may exhibit much superior photocatalytic activity compared to conventional photocatalysts, particularly in a visible region of 400 nm or more. In addition, the photocatalytic reactivity capable of adsorbing and decomposing decomposition targets on the surface is improved, so that photocatalytic activity is obtained in various humidity regions, and excellent photocatalytic activity can be exhibited even in dry conditions of 30% or less humidity.

According to one example, the photocatalyst particles, 5 (m ² /g) or more; 5 (m ² /g) to 1000 (m ² /g); Alternatively, it may have a specific surface area of 5 (m ² /g) to 100 (m ² /g), and the average pore size may be 50 nm or less. By introducing a metal oxide derived from an organometallic compound on the surface of the inorganic oxide, the amount of adsorption of the decomposition target is increased on the surface of the photocatalyst, and the photocatalytic reactivity is increased, thereby improving the efficiency of the photocatalyst.

According to an embodiment of the present invention, the photocatalyst is applied to decomposition of various harmful substances, that is, it can be used to treat environmental pollutants, odor substances, organic compounds, acid gases, and the like. For example, it is used for adsorption and/or photolysis of at least one of a gas, a liquid, and a solid material, and may exhibit photoactivity by light energy including various rays such as halogen lamps, xenon lamps, sunlight, and light emitting diodes. More specifically, the gas includes VOC (Volatile Organic Compounds) such as acidic, basic gas, acetaldehyde, and ketones, hydrocarbons of aromatic and aliphatic hydrocarbons (Paraffin and Olefin), ozone gas, organic And inorganic glass gas, and more specifically, carbon dioxide, carbon monoxide, NOx, SOx, HCl, HF, NH ₃ , methylamine, formaldehyde, hydrogen sulfide, amine, methyl mercaptan, hydrogen, oxygen, nitrogen, methane, paraffin , Olefins, and the like. The liquid includes formaldehyde, acetaldehyde, benzene, toluene, MEK (Methyl Ethyl Ketone), trichloroethylene, disinfectant, gasoline, diesel, oil, alcohol, Phenol, dye, etc., and the solid may be a transition metal, precious metals such as Pt, Pd, ions and/or particles such as Hg and Cr, nanoparticles of 100 nm or less, but is not limited thereto.

The sound insulation wall comprising a visible light active photocatalyst according to another aspect of the present invention includes at least one sound insulation panel corresponding to an embodiment of the present invention, and the sound insulation panel is in a dry condition of 30% or less and a humidity of 400 nm or more. It includes a photocatalyst having photoactivity in the visible region.

1 is a flow chart showing a method for manufacturing a photocatalyst according to the present invention, according to an embodiment of the present invention. According to an example, after manufacturing a photocatalyst in the manner shown in FIG. 1, a coating layer including a photocatalyst according to an embodiment of the present invention is formed by mixing and dispersing the photocatalyst in the process of manufacturing the soundproof panel described above. Panels can be manufactured.

Hereinafter, a description will be given of a method for manufacturing a photocatalyst exhibiting visible light activity, which is a characteristic technique of the present invention with reference to FIG. 1.

The method of manufacturing the photocatalyst includes: preparing an inorganic oxide; Forming a metal oxide layer on the inorganic oxide; And forming a metal oxide layer derived from an organometallic oxide by heat treatment after the step of forming the metal oxide layer.

The preparing of the inorganic oxide is a step of preparing an inorganic oxide dispersion or applying the inorganic oxide on a substrate, and the dispersion is applied with an aqueous solvent, an oil solvent, or a mixture of both, and the substrate is a silicon substrate , A wafer, a glass substrate, a semiconductor substrate, a metal substrate, and the like. The inorganic oxide may be applied by spin coating, roll coating, spray coating, dip coating, flow coating, doctor blade method, or the like.

In the forming of the organometallic oxide layer, an organometallic oxide film may be formed using a wet coating method, a sputtering method, or a vapor deposition method. As an example, the organometallic oxide film may be a ferrocene film. Preferably, a deposition method such as ALD (atomic layer deposition), CVD (temperature-regulated chemical vapor deposition) is used, and more preferably, TR-CVD (temperature-regulated chemical vapor deposition) is used. A ferrocene layer can be formed. As an example, when TR-CVD is applied, the amount of iron oxide deposited on the inorganic oxide can be easily controlled through the control of the amount of ferrocene, and the manufacturing process of the photocatalyst can be simplified and the photocatalyst can be efficiently provided.

The step of forming the organometallic oxide layer may be performed at room temperature to 120°C, preferably 40°C to 100°C; More preferably, it may be carried out at 60 ℃ to 100 ℃. That is, when TR-CVD is applied, it may be carried out at 60° C. to 100° C. in order to induce deposition by the vaporization process of the organic metal oxide layer.

The step of forming the organometallic oxide layer may be performed in an air or oxygen atmosphere under atmospheric conditions, and may further include an inert gas.

The organometallic oxide layer in the step of forming the organometallic oxide layer includes 0.01% to 20% by weight of ferrocene relative to the inorganic oxide, and may form the ferrocene layer.

In the forming of the organometallic oxide-derived metal oxide layer, for example, the organometallic oxide layer may be partially or completely oxidized to a metal oxide through heat treatment, and impurities such as carbon residue may be removed.

Forming the metal oxide layer derived from the organometallic oxide, 50 ℃ to 900 ℃; Alternatively 100° C. to 800° C.; It can be heat-treated in two or more steps at temperature.

For example, the step of forming the metal oxide layer derived from the organometallic oxide includes performing a first heat treatment at a temperature of 100°C to 300°C and a second heat treatment at a temperature of 300°C to 900°C, each step It can be heat treated at different temperatures. Each of the steps is performed for 1 minute to 20 hours, respectively, by air, 20% or more; It may be carried out in an air or inert gas atmosphere containing 40% or more oxygen.

That is, the step of performing the first heat treatment may be an annealing process for depositing a metal oxide in which the metal oxide is converted into a metal oxide by a reaction of an organometallic oxide and oxygen. The second heat treatment step may be a post heat treatment step after the first heat treatment step, and may be an annealing process for improving the activity and performance of the photocatalyst by removing impurities such as carbides.

Hereinafter, the present invention will be described in more detail by examples and comparative examples.

Photocatalyst preparation and property evaluation

First, a photocatalyst, a characteristic component of the present invention, was prepared using ferrocene.

However, the following examples are introduced to prove the manufacturing process of the photocatalyst of the present invention and the effects realized therefrom, and are only examples of selecting ferrocene as an organometallic oxide, and the content of the present invention is limited to the following examples. It does not become.

Example 1

With reference to Fig. 2 of the TR-CVD (temperature controlled chemical vapor deposition) reactor, utilizing a temperature controlled chemical vapor deposition as shown in Figure 3 produce a photocatalyst (Fe-TiO ₂₎ of the iron oxide particles in the nano-scale deposited on the TiO ₂ I did. More specifically, 0.02 g of ferrocene, a precursor of iron, is placed in a container made of quartz on the inner bottom of a reactor made of stainless steel surrounded by a heating band. After placing 3 g of TiO ₂ (TiO ₂ , P-25, Evonik, particle size: 25 nm) in the center of the reactor in a container made of stainless steel wire mesh, the reactor is sealed with polyimide tape. The ferrocene deposition process was performed by the TR-CVD vaporization process at 60° C. for 2 hours at the temperature of the reactor, and then, the temperature was raised to 200° C. and maintained for 12 hours to convert to iron oxide.

Then prepare a final iron oxide -TiO ₂ hybrid photocatalytic nano-structure (or, expressed as Fe-TiO ₂₎ by an additional heat treatment for 2 hours at 750 ℃ in dry air gas atmosphere to remove the TiO _2. The content of iron deposited on TiO ₂ under this condition is about 0.09 wt%.

Example 2

An iron oxide-TiO ₂ hybrid nanostructure photocatalyst was prepared in the same manner as in Example 1, except that 0.05 g of the iron precursor Ferrocene was applied. The content of iron deposited on TiO ₂ under this condition is about 0.13 wt%.

Example 3

An iron oxide-TiO ₂ hybrid nanostructured photocatalyst was prepared in the same manner as in Example 1, except that 0.1 g of the iron precursor Ferrocene was applied. The content of iron deposited on TiO ₂ under this condition is about 0.65 wt%.

Example 4

An iron oxide-TiO ₂ hybrid nanostructure photocatalyst was prepared in the same manner as in Example 1, except that 0.3 g of the iron precursor Ferrocene was applied. The content of iron deposited on TiO ₂ under this condition is about 1.81 wt%.

4 shows an image of a photocatalyst applied to the present invention manufactured according to an embodiment of the present invention.

The prepared photocatalyst (Fe-TiO ₂ ) was compared with a TiO ₂ photocatalyst coated with a general iron oxide, and transparency and color were compared and shown in FIG. 4. 4, the photocatalyst coated with ferrocene-derived iron oxide according to the present invention (Fe-TiO ₂ ) is more transparent and softer than the photocatalyst coated with iron oxide (Fe ₂ O ₃ ) (Fe ₂ O ₃ -TiO ₂ ) It can be seen that it has a yellow color.

A TEM image (an image measured by a transmission electron microscope) of the prepared photocatalyst (Fe-TiO ₂ ) was measured and shown in FIG. 5. 5 shows that as the iron content decreases, the size of the iron oxide particles deposited on the surface of Fe-TiO ₂ decreases.

The specific surface area (BET) and BJH average pore size through nitrogen adsorption analysis of the prepared photocatalyst (Fe-TiO ₂ ) were measured and shown in Table 1.

0.13 wt% Fe-TiO ₂ 0.65 wt% Fe-TiO2 1.81 wt% Fe-TiO ₂ BET Surface area(m ² /g) 11.6259 10.3426 8.3939 BJHAdsorption average pore size(nm) 13.2 12.5 13.9

Looking at Table 1, it can be seen that even when the iron content of Fe-TiO ₂ changes, the specific surface area and the average pore size do not change significantly, and it can be seen that the mesopores of Fe-TiO ₂ are formed.

Evaluation Example 1

The photocatalyst (Fe-TiO ₂ ) of Example 1 was put in a 5.3 L batch reactor with a volume of quartz glass on the top, and the initial concentration of acetaldehyde was 66 ppm, and dry air (relative humidity: -33%, total pressure was 760). torr) and by irradiating the visible light region with a white soundproof panel at room temperature, photodecomposition properties of acetaldehyde were analyzed. Acetaldehyde in the reactor was visually measured using gas chromatography. The results are shown in FIG. 6.

6 is a graph showing (a) a change in the number of moles of acetaldehyde, and (b) a change in the number of moles of carbon dioxide generated as a result of the photolysis reaction of acetaldehyde according to the irradiation time of visible light (white light) under a humidity condition of 33%, and FIG. Looking at, it can be seen that the photocatalyst (Fe-TiO ₂ ) prepared in Example is photodegraded by photocatalytic activity by irradiation with visible light (white light), and the decomposition efficiency in visible light when the ferrocene deposition amount is 0.09 wt%. You can see the biggest one. In addition, it can be seen that as the iron content decreases, the acetaldehyde photolysis rate of Fe-TiO ₂ increases.

Evaluation Example 2

The photocatalyst (Fe-TiO ₂ ) having a deposition amount of ferrocene of 0.13 wt% was analyzed for photodecomposition properties of acetaldehyde in the same manner as in Evaluation Example 1 in a dry condition without humidity and a humidity condition of ~33%. Acetaldehyde and carbon dioxide in the reactor were periodically measured using gas chromatography. The results are shown in FIGS. 8 and 9.

FIG. 7 shows the change in the number of moles of carbon dioxide generated as a result of (a) the number of moles of acetaldehyde and (b) the change in the number of moles of acetaldehyde according to the time of irradiation with visible light when the acetaldehyde photolysis experiment was performed under dry conditions and 33% humidity conditions. Referring to FIG. 7, in the same acetaldehyde concentration section indicated by the dotted line, the slopes of the two graphs were similar, showing that the acetaldehyde photolysis activity remained similar in visible light irradiation regardless of the presence or absence of humidity.

In addition, it can be seen that the generation of carbon dioxide increases with the light irradiation time, which is the generation of carbon dioxide by complete oxidation of acetaldehyde.

8 shows the change in the number of moles of carbon dioxide generated as a result of (a) the number of moles of acetaldehyde and (b) the number of moles of carbon dioxide generated as a result of the photolysis reaction of acetaldehyde according to the visible light irradiation time when repeatedly used in the acetaldehyde photolysis experiment under 33% humidity conditions. It is a graph shown, and it can be seen from FIG. 8 that high photocatalytic activity is maintained even in repeated photolysis experiments.

In general, in the present invention, TiO ₂ on which iron oxide is deposited (hereinafter, Fe-TiO ₂ ) was used in the photolysis experiment of acetaldehyde, one of the representative volatile organic compounds, and the photolysis activity of acetaldehyde of Fe-TiO ₂ according to the content of iron oxide Was compared. As a result, when the iron content was as low as about 0.09 wt%, the photolysis activity of acetaldehyde of Fe-TiO ₂ was highest, and about 70% of the initial acetaldehyde concentration (~95 mol ppm) decreased within 20 hours. In addition, in general, the activity of the photocatalyst is greatly affected by humidity, but Fe-TiO ₂ prepared in the present invention showed similar catalytic activity under dry and humidity conditions, confirming that the photocatalytic activity is not sensitive to humidity. As a result of conducting nitrogen adsorption experiments of Fe-TiO ₂ having various iron contents, it was confirmed that the iron content did not significantly affect the total specific surface area of the photocatalyst. In addition, as the photocatalytic activity of Fe-TiO ₂ was greatly influenced by the iron content, it can be seen that the electronic structure of the interface between the deposited iron oxide nanoparticles and TiO ₂ is more important than the surface structure of the photocatalyst. . In addition, it was confirmed through a transmission electron microscope that the smaller the iron content is, the smaller the size of the iron oxide particles present on the surface. When the iron oxide particles of 1 to 3 nanometers are deposited, the photocatalytic activity can be increased. From the analysis results, when very small iron oxide nanoparticles have a content of about 0.09 wt%, Fe-TiO ₂ absorbs light in the visible light region and separates electron/hole pairs most efficiently, resulting in oxygen/ It reacts with water to produce radicals that can rapidly decompose acetaldehyde. On the other hand, if the target organic material is not completely oxidized but partially oxidized and remains on the surface of the photocatalyst to block the active site, the activity of the photocatalyst decreases, which is pointed out as one of the biggest problems of the photocatalyst. However, it was confirmed that the Fe-TiO ₂ prepared in the present invention maintained the same catalytic activity even in repeated acetaldehyde photolysis experiments, and thus there was no problem of deteriorating catalytic activity.

Manufacturing of sound insulation walls including sound insulation panels

The photocatalyst prepared by the above method was prepared in the form of a composition, and a coating layer was formed to a thickness of 5 mm on a generally used soundproof panel (coated), and dried. As a result of measuring the air purification effect, it was confirmed that the photocatalyst functions in the same manner even in the state of being formed as a coating layer.

9 is a structural diagram schematically showing the structure of a sound insulation wall including a sound insulation panel including a photocatalyst manufactured according to an embodiment of the present invention.

As shown in FIG. 9, the sound insulation panels 100, 100 ′ and 100 ″ according to the exemplary embodiment of the present invention may be designed to be included in the sound insulation wall 200.

Although the embodiments have been described by the limited embodiments and drawings as described above, various modifications and variations are possible from the above description to those of ordinary skill in the art. For example, even if the described techniques are performed in a different order from the described method, and/or the described components are combined or combined in a form different from the described method, or are replaced or substituted by other components or equivalents. Appropriate results can be achieved. Therefore, other implementations, other embodiments, and claims and equivalents fall within the scope of the claims to be described later.

Claims (10)

materials;
Including; a coating layer comprising a photocatalyst formed on at least a portion of the surface of the substrate,
The photocatalyst includes an inorganic oxide particle and a metal oxide layer derived from an organometallic compound formed on the inorganic oxide particle, and has photoactivity in a visible light region of 400 nm or more,
The specific surface area of the photocatalyst is 5 (m ² /g) or more, and the average pore size is 50 nm or less,
The inorganic oxide contains at least one selected from the group consisting of oxides containing at least one of Ti, Zn, Al and Sn,
The metal oxide layer contains 0.001 to 10% by weight of iron oxide relative to the inorganic oxide,
The photocatalyst has photoactivity in dry conditions of 30% or less humidity,
The metal oxide layer contains ferrocene-derived iron oxide,
A soundproof panel for roads containing a visible light active photocatalyst.
The method of claim 1,
The coating layer further comprises a polymer resin, a silicone resin, silica and a water repellent fluororesin,
A soundproof panel for roads containing a visible light active photocatalyst.
The method of claim 1,
The coating layer further comprises at least one metal material selected from the group consisting of silver, copper, zinc, and platinum group metal elements,
A soundproof panel for roads containing a visible light active photocatalyst.
The method of claim 1,
The coating layer, which includes RB ceramics, CRB ceramics, or both,
A soundproof panel for roads containing a visible light active photocatalyst.
delete delete delete The method of claim 1,
The inorganic oxide does not contain an inorganic oxide containing iron,
The metal oxide layer is that ferrocene deposited on the inorganic oxide is heat treated,
A soundproof panel for roads containing a visible light active photocatalyst.
The method of claim 1,
The metal oxide contains at least one of the compounds represented by the following formula (1),
A soundproof panel for roads containing a visible light active photocatalyst.

[Formula 1]
Me _x O _Y H _Z
(Me is one or more metal elements from Groups 1 to 3, X, Y, and Z are each selected from 0 to 3, and X and Y are not 0.)
Including at least one soundproof panel of claim 1,
The soundproof panel comprises a photocatalyst having photoactivity in a dry condition of 30% or less humidity and a visible light region of 400 nm or more,
A sound barrier comprising a visible light active photocatalyst.

Images