CN115569648A - Photocatalyst composite material, method for producing photocatalyst composite material, and photocatalyst device - Google Patents

Photocatalyst composite material, method for producing photocatalyst composite material, and photocatalyst device Download PDF

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CN115569648A
CN115569648A CN202211426631.0A CN202211426631A CN115569648A CN 115569648 A CN115569648 A CN 115569648A CN 202211426631 A CN202211426631 A CN 202211426631A CN 115569648 A CN115569648 A CN 115569648A
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photocatalyst
particles
layer
particle diameter
composite
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CN115569648B (en
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信田直美
内藤胜之
横田昌广
千草尚
太田英男
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Toshiba Corp
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Abstract

The invention provides a photocatalyst composite material which has high activity, can be simply manufactured and is not easy to strip, a manufacturing method thereof and a photocatalyst device. A photocatalyst composite material comprising a base material and a photocatalyst layer formed of photocatalyst particles, wherein the average particle diameter of the photocatalyst layer in contact with the surface of the base material is smaller than the average particle diameter of the surface of the photocatalyst layer.

Description

Photocatalyst composite material, method for producing photocatalyst composite material, and photocatalyst device
The present application is a divisional application of an invention patent application having an application date of 2019, 9 and 12 months, and an application number of 201910863185.1, and having an invention name of "photocatalyst composite material, method for producing photocatalyst composite material, and photocatalyst apparatus".
Technical Field
Embodiments of the present invention relate to a photocatalyst composite material, a method for producing a photocatalyst composite material, and a photocatalyst apparatus.
Background
It is known that a photocatalyst generates excited holes by light and promotes a strong oxidation reaction. As a photocatalyst having such an action, various photocatalysts are known, and the accelerating action is utilized for decomposition and removal of harmful organic molecules, sterilization, maintenance of hydrophilicity of a base material, and the like.
When the photocatalyst is to be applied to such an application, for example, a photocatalyst composite material in which the photocatalyst is supported on a base material may be brought into contact with a substance to be treated. In order to effectively perform the treatment by this method, the amount of the photocatalyst supported on the substrate is generally increased. However, the increase in the amount of the photocatalyst directly leads to an increase in cost, and there is a problem that the photocatalyst is easily peeled off from the substrate. In addition, in order to increase the surface area, a shape such as a fractal structure may be adopted, but the production method is easy to become complicated, and there is room for study.
Documents of the prior art
Patent document
Patent document 1: japanese patent No. 4163374
Patent document 2: japanese patent laid-open publication No. 2000-135755
Disclosure of Invention
Problems to be solved by the invention
In view of the above problems, it is desirable to provide a photocatalyst composite material having high activity and being less likely to be peeled off, a method for easily producing the photocatalyst composite material, and a photocatalyst apparatus provided with the photocatalyst composite material.
Means for solving the problems
The photocatalyst composite material according to the embodiment includes a base material and a photocatalyst layer including photocatalyst particles, and the substrate-side interface of the photocatalyst layer is S b Setting the opposite side interface as S t When it is, S is as above b The average particle diameter r of the photocatalyst particles in the vicinity b Less than S t The average particle diameter r of the photocatalyst particles in the vicinity t
In addition, the method for producing a photocatalyst composite material according to the embodiment includes the steps of: a step of coating a dispersion liquid containing the 1 st photocatalyst particles on a substrate; and applying a dispersion containing 2 nd photocatalyst particles having an average particle diameter larger than that of the 1 st photocatalyst particles.
In addition, the photocatalyst apparatus according to the embodiment includes:
the photocatalyst composite material,
A light irradiation member for generating photocatalytic activity on the substrate, and
a supply member for supplying a substance to be treated to the photocatalyst composite material,
the photocatalyst composite material having catalytic activity by the light promotes chemical reactions for treating the substance.
Drawings
Fig. 1 is a schematic view of a photocatalyst composite according to an embodiment.
Fig. 2 is a schematic diagram of a method for producing a photocatalyst composite according to an embodiment.
Fig. 3 is a schematic view of a photocatalyst apparatus according to an embodiment.
Description of the symbols
10 \8230, photocatalyst composite material, 11 \8230, base material, 12 \8230, photocatalyst layer, 21 \8230, no. 1 photocatalyst particle, 22 \8230, no. 2 photocatalyst particle, 30 \8230, photocatalyst device, 31 \8230, photocatalyst composite material, 32 \8230, light irradiation member, 33 \8230, member for supplying substance with photocatalysis to base material, 34 \8230, reaction cavity
Detailed Description
Hereinafter, embodiments will be described with reference to the drawings.
Note that, the same reference numerals are given to the common components in the embodiments, and overlapping description is omitted. The drawings are schematic views for explaining the embodiments and facilitating understanding thereof, and the shapes, dimensions, proportions, and the like thereof are different from those of actual apparatuses, and they can be appropriately designed and changed by referring to the following description and known techniques.
(embodiment mode 1)
As shown in fig. 1, a photocatalyst composite material 10 according to an example of the embodiment includes a substrate 11 and a photocatalyst layer 12. The photocatalyst layer 12 has a substrate-side interface S b And opposite side interface S t . In the photocatalyst layer illustrated in fig. 1, the particles having a small particle diameter are represented by S b The particles with large particle size are localized in the S t The side is locally present.Therefore, if it is to be at S b Average particle diameter r of nearby photocatalyst particles b And is at S t Average particle diameter r of nearby photocatalyst particles t By comparison, then r b Becomes smaller.
Wherein is said to be S b Near or S t The vicinity may be generally set to be a region obtained by bisecting the photocatalyst layer so as to be close to S b And near S t The area of the region(s).
In FIG. 1, as a schematic diagram, shown at S b The side is provided with "small particles" at S t The side is provided with 2 kinds of structures of "macro-particles". When the particle size distribution of the photocatalyst particles is measured, the distribution curve has 2 peaks. However, the method is not limited thereto, and 2 or more kinds of particles having different sizes may be layered or S may be selected from b Direction S t And the particle diameter is continuously changed. In the former case, the particle size distribution curve has 2 or more peaks, but in the latter case, there is a case where no clear peak appears in the particle size distribution.
By disposing the photocatalyst particles in this manner, excellent effects can be obtained. First, when the photocatalyst particles are small, they tend to be easily peeled off by water flow or air flow in water or air. However, since particles present in the vicinity of Sb and in contact with the surface of the substrate are easily strongly adsorbed by the substrate, they are not easily peeled off even if their average particle diameter is small. Further, when the photocatalyst particles in the vicinity of Sb are small, the surface area of the photocatalyst present in the vicinity of the substrate surface is increased, and therefore, high catalytic activity is easily obtained.
On the other hand, the photocatalyst particles existing in the vicinity of St are more difficult to be exfoliated as the average particle diameter thereof is larger. In addition, since the space between the particles is enlarged as the particle diameter is larger, the substance treated by the photocatalyst or the decomposition product is easily diffused.
The particle size or average particle size of the photocatalyst particles can be determined by observing the surface of the photocatalyst layer imaged by TEM (Transmission Electron microscope)The surface and cross section. Specifically, the cross section of the photocatalyst layer was observed by TEM at 100 ten thousand times, and the diameter when the projected area of the particles was converted into a circle having the same area by image processing was set as the particle diameter. In addition, S b Average particle diameter r of nearby photocatalyst particles b Or S t Average particle diameter r of nearby photocatalyst particles t Is configured at S b Nearby or S t The average of at least 100 particle diameters of the photocatalyst particles in the vicinity is determined.
In an embodiment, r b Preferably 2 to 50nm. If r b When the particle size is 2nm or more, the dispersion of the photocatalyst particles in the production process has high stability, and the possibility of dissolution or aggregation is low. On the other hand, if r b When the particle diameter is 50nm or less, the photocatalyst particles can be sufficiently adhered to the surface of the substrate, and the total surface area of the photocatalyst particles becomes large, whereby high catalytic activity can be obtained. In addition, r t Preferably 40 to 500nm. If r is t When the particle size is 40nm or more, the space between the particles becomes wide, and therefore, a substance to be treated is sufficiently diffused into the photocatalyst layer to obtain high catalytic activity, and the photocatalyst layer is less likely to be peeled off by a gas flow, a water flow, or the like. On the other hand, if r t When the particle size is 500nm or less, the dispersibility of the dispersion liquid in the production process tends to be high, and the catalytic activity tends to be high.
The average particle diameter of all the photocatalyst particles contained in the photocatalyst layer is preferably 2 to 500nm, more preferably 10 to 400nm, and particularly preferably 20 to 200nm, from the viewpoints of stability of the dispersion, workability when applied to a substrate, and exhibition of a photocatalytic function.
As the photocatalyst particles, particles containing metal oxides such as tungsten oxide, titanium oxide, zinc oxide, niobium oxide, and tin oxide are used. These photocatalyst particles may be used in combination of 2 or more. A photocatalyst containing tungsten oxide is preferable because it has visible light responsiveness. In particular, it is preferable that the tungsten oxide crystal has a monoclinic or triclinic crystal structure because the catalyst activity is likely to be high.
The photocatalyst particles having different chemical compositions may be used in combination. This makes it possible to improve the durability of the photocatalyst layer or to more effectively utilize the light energy irradiated to the catalyst, as well as to combine photocatalysts having different functions. For example, when a material which is easily positively charged is used for the base material, the value S is the value b Tungsten oxide which is easily negatively charged is arranged in the vicinity of the tungsten oxide t When titanium oxide is disposed in the vicinity of the photocatalyst layer, the adhesion of the photocatalyst layer to the base material is improved, and the durability is improved. In this case, the average particle diameter of tungsten oxide is smaller than the average particle diameter of titanium oxide. In addition, by combining photocatalysts having a large difference in light absorption spectrum, each photocatalyst particle can efficiently absorb light and exhibit catalytic activity. For example, by at S b Tungsten oxide having an absorption edge of about 470nm and having light absorption is disposed in the vicinity of the tungsten oxide t Titanium oxide having an absorption end of light absorption of about 400nm is arranged in the vicinity, and tungsten oxide at a position distant from the light absorption surface can efficiently absorb light.
In the photocatalyst layer, it is preferable that the photocatalyst particles are contained in an amount of 20 to 100 mass% based on the total mass of the photocatalyst layer in order to obtain high catalytic activity. The photocatalyst layer may be composed of only photocatalyst particles, but may contain a promoter, silver nanowires, a binder, and the like, which will be described later.
The photocatalyst layer of the present embodiment may further include a co-catalyst. The co-catalyst is usually contained in the form of nanoparticles. As the material of the co-catalyst, a metal element compound is preferable. For example, a promoter for a tungsten oxide photocatalyst may comprise at least 1 metal element selected from Ti, sn, zr, mn, fe, ni, pd, pt, cu, ag, zn, al, ru, and Ce. Among them, metal oxides of Cu, fe, ni, or composite oxides thereof are preferable. The content of the metal element such as a transition metal element with respect to the total amount of the photocatalyst particles and the promoter particles may be set in the range of 0.01 to 50 mass%. When the content of the transition metal element exceeds 50 mass%, the transmittance of light tends to decrease and the activity of the catalyst tends to decrease. The content of the transition metal element is more preferably 10% by mass or less, and still more preferably 2% by mass or less. The lower limit of the content of the transition metal element is not particularly limited, but the content is preferably set to 0.01 mass% or more in view of more effectively exhibiting the effect of adding the promoter. The oxides of the transition metals mentioned above are easily positively charged. Noble metal promoter particles such as Pt and Pd are also preferable because they can be easily positively charged by protection with an organic polymer.
In an embodiment, the Zeta potential may be measured by electrophoretic light scattering. Specifically, the measurement can be performed by combining a capillary sample cell with Zetasizer Nano ZS (trade name) manufactured by Malvern corporation. The pH of the dispersion is adjusted by adding dilute hydrochloric acid and a dilute aqueous solution of potassium hydroxide to pure water in which photocatalyst-containing substances or promoter particles are dispersed.
The promoter is a substance that further enhances the photocatalytic action of the photocatalyst particles. More specifically, for example, copper oxide or the like as a p-type semiconductor is preferably used as a promoter for tungsten oxide as an n-type semiconductor. Since the energy level of the conduction band of tungsten oxide is slightly higher than the valence band of the promoter, when the tungsten oxide is irradiated with light, electrons excited from the valence band to the conduction band move to the valence band of the promoter, and are further excited by light and excited to the conduction band of the promoter, so-called Z-Scheme can increase the energy level of electrons by visible light to reduce oxygen in the air and generate oxygen radicals or hydrogen peroxide. Holes are generated in the valence band of tungsten oxide, and organic molecules and the like are decomposed. Oxygen radicals or hydrogen peroxide also decompose organic molecules and the like.
In addition, the metal oxide promoter has a positive Zeta potential. In contrast, photocatalyst particles such as tungsten oxide have a negative Zeta potential. Therefore, the photocatalyst particles and the promoter particles are easily adsorbed, and the catalytic activity is easily further enhanced.
The photocatalyst layer of the present embodiment may further include silver nanowires. Although tungsten oxide and spherical silver particles that are likely to be negatively charged do not easily form a uniform composite, a photocatalyst particle is easily held between the mesh-like structures formed of silver nanowires, and thus a uniform composite structure is easily formed.
In addition, silver nanowires generally tend to aggregate easily, but in the photocatalyst dispersion liquid according to the embodiment, the occurrence of aggregation is small. This is believed to be due to: the coexisting photocatalyst particles also function as a dispersant and are less likely to cause aggregation.
In addition, the photocatalyst layer is also mechanically stable due to the mesh structure formed by the silver nanowires, and the silver nanowires are less likely to flow out. Further, the antibacterial activity is generated by a very small amount of silver ions, and the antibacterial activity is maintained for a long time. Further, the silver nanowire has a photo-electric field enhancing effect by plasmon resonance, and has an effect of improving the activity of the photocatalyst particles around the silver nanowire.
The shape of the silver nanowires is not particularly limited, and is selected so as to optimize the desired plasmon effect, the dispersion state in the dispersion liquid, or the like. For example, in an embodiment, the silver nanowires preferably have an average diameter of 10 to 200nm, an average length of 1 to 50 μm, and an average aspect ratio of 100 to 1000. More preferably, the average diameter is 20 to 100nm, the average length is 4 to 30 μm, and the average aspect ratio is 200 to 500. The average diameter or average length of the silver nanowires was measured by observing the surface and cross section of the photocatalyst layer photographed at 20 ten thousand times by SEM (Scanning Electron Microscopy). The diameter of the silver nanowires corresponds to the length of the width of the planar image of the silver nanowires. The length of the silver nanowires corresponds to the length of the silver nanowire planar image in the longitudinal direction. When the silver nanowire is bent, the length of the bent silver nanowire is the length of the bent silver nanowire when the bent silver nanowire is formed into a straight shape. Regarding one silver nanowire, in the case where the width varies in the length direction, the width was measured at different 3 points and set as the width of the nanowire on average. The average of these values was obtained from the measured values of 50 nanowires each selected at random.
Regarding the mixing ratio of the photocatalyst particles and the silver nanowires, when the silver nanowires are combined, the mass of the silver nanowires is preferably 1/100000 to 1/10 times, more preferably 1/1000 to 1/10 times, based on the mass of the photocatalyst particles. When the mixing ratio of the silver nanowires is large, light absorption by the silver nanowires tends to easily inhibit photoexcitation of the photocatalyst, and when the mixing ratio of the silver nanowires is small, the effect of improving the catalytic activity by the silver nanowires tends to be small.
The photocatalyst layer of the present embodiment may further contain alumina hydrate. The alumina hydrate being Al 2 O 3 ·(H 2 O) x (0<x is less than or equal to 3). The alumina hydrate particles (hereinafter, simply referred to as alumina particles) are excellent as a binder and also prevent the catalyst particles from aggregating with each other, thereby stabilizing the photocatalyst dispersion. When coated on a substrate, a uniform and firm film is easily formed.
The alumina particles may have various forms, but boehmite (x = 1) or pseudoboehmite (1-s-x-s-2) is preferable. Boehmite or pseudoboehmite is stable in a polar solvent such as water, and a strong coating film can be easily formed by coating and drying. In particular, the alumina particles having a fibrous or plate-like shape have a large effect of preventing aggregation of catalyst particles.
When alumina particles are used, the mixing ratio of the photocatalyst particles to the alumina particles is preferably 0.005 to 0.1 times, more preferably 0.01 to 0.03 times, the mass of the alumina particles based on the mass of the photocatalyst particles. If the amount of the alumina hydrate is too large, the photocatalytic activity of the photocatalyst layer may be lowered, and if the amount of the alumina hydrate is too small, the stability of the photocatalyst layer may be lowered.
The shape of the alumina particles is not particularly limited, and may be, for example, a fibrous shape. When the alumina particles are in a fibrous form, they preferably have a diameter of 1 to 10nm and a length of 500 to 10000nm. More preferably, the diameter is 2 to 8nm and the length is 800 to 60000nm, still more preferably 3 to 6nm and the length is 1000 to 3000nm.
The photocatalyst layer may further contain another oxide. For example, silicon oxide has a function of increasing the hydrophilicity of the photocatalyst layer. In addition, tin oxide increases the conductivity of the photocatalyst layer to prevent electrification, and makes dirt less likely to adhere.
The photocatalyst layer may also contain graphene oxide or graphite oxide. This prevents the catalyst particles from agglomerating with each other, and can maintain stability and photocatalytic activity for a long period of time. Regarding the mixing ratio of the graphene oxide or graphite oxide and the photocatalyst particles contained in the photocatalyst layer, the mass of the graphene oxide or graphite oxide based on the mass of the photocatalyst particles is preferably 1/200,000 to 1/100 times, more preferably 1/100,000 to 1/1000 times, and particularly preferably 1/50,000 to 1/10,000 times. When the mixing ratio is small, the stability improving effect tends to be small, and when the mixing ratio is large, the photocatalytic activity improving effect tends to be small.
In an embodiment, a base layer may be disposed between the substrate and the photocatalyst layer. The layer containing an inorganic oxide is preferable as the underlayer since the layer can prevent the deterioration of the base material due to the photocatalyst and can prevent the peeling from the photocatalyst layer. Examples of the inorganic oxide include silica, alumina, and zirconia. The inorganic oxide is more preferably an aluminum oxide. The base material often has a negative Zeta potential, and an aluminum oxide which easily has a positive Zeta potential easily stably covers the base material. In addition, the photocatalyst particles and silver nanowires having a negative Zeta potential can be easily and stably supported.
In an embodiment, the coverage of the base layer with respect to the surface area of the base material is preferably 80% or more. The coverage is a ratio of an area covered with the foundation layer to a surface area of the base material. When the coverage is in such a range, the catalyst adhesion of the underlayer and the effect of protecting the substrate can be obtained. The coverage can be determined by measuring the area of the surface of the base material and the area of the portion covered with the foundation layer by observing the base material at 25 times by SEM and calculating the ratio of the areas.
The Zeta potential of the base material or the underlayer can be measured by an electrophoretic light scattering method using a flat-plate Zeta potential measuring sample cell using polystyrene latex as tracer particles, using Zetasizer Nano ZS manufactured by Malvern corporation. The pH was adjusted by adding dilute hydrochloric acid and dilute aqueous potassium hydroxide solution to pure water.
The substrate may be selected from any materials such as organic materials and metallic materials, and examples thereof include metals, ceramics, papers, and polymer films. The base material may be a smooth surface material or a porous material. The porous body is preferable because the surface area can be increased and the photocatalyst supporting amount can be easily increased. Further, it is preferable that the material of the substrate is a material containing an organic substance because coloring and surface modification are easy.
The polymer film can be made into a flexible transparent film, so that the application range of the photocatalyst composite material can be expanded. As the polymer material, a material having high visible light transparency such as polyethylene terephthalate, polycarbonate, polyethylene naphthalate, and acrylic resin can be preferably used. Also preferred is a curable resin which forms a strong surface. In particular, polyethylene terephthalate is preferable because it is highly flexible and has good adhesion to graphene oxide when used. Also preferred is a curable resin which forms a firm surface.
The substrate preferably has a negative Zeta potential in water at 20 ℃ and pH 6. By using such a base material, the association of catalyst particles can be suppressed, and a uniform film can be easily obtained.
The surface of the substrate may be smooth or may have irregularities. When the surface roughness of the base material is increased, the surface area of the base material surface is increased, and a larger amount of the photocatalyst particles in the photocatalyst layer on the base material can be supported.
For example, the absolute value of the arithmetic average roughness Ra of the surface of the base material is preferably 0.2 to 20 μm. The arithmetic average roughness Ra can be measured according to JIS standard. When the arithmetic mean roughness Ra is less than 0.2 μm, the contact area between the photocatalyst and the substrate becomes small, and the peeling tends to be easy. When the arithmetic mean roughness Ra is greater than 20 μm, the photocatalyst particles tend to accumulate only in the recesses of the base material, and the film thickness of the photocatalyst layer becomes too large, so that activation of the photocatalyst in the lower portion by light is unlikely to occur.
The "photocatalytic action" in the embodiment refers to decomposition of harmful substances such as ammonia and aldehydes, decomposition and deodorization of unpleasant odor of cigarettes and pets, antibacterial action and antiviral action against staphylococcus aureus and escherichia coli, and antifouling action in which dirt is not easily adhered.
(embodiment 2)
The photocatalyst composite according to the embodiment can be produced by any method, but can be produced by a method described below, for example.
Fig. 2 (a) to (C) are schematic diagrams showing an example of the method for producing the photocatalyst composite according to embodiment 2.
First, a dispersion 21 containing the 1 st photocatalyst particles is applied to the surface of the substrate 11 to form a 1 st photocatalyst particle layer 21a (fig. 2 a). The 1 st photocatalyst particle may be selected from the photocatalyst particles described above. The 1 st photocatalyst particle preferably has an average particle diameter of 2 to 50nm. The dispersion may contain promoter particles, silver nanoparticles, and the like as needed. Water is generally used in the dispersion medium. However, an alcohol may be mixed in, if necessary. When the dispersion medium contains an alcohol, the surface tension of the dispersion liquid is lowered, and the dispersion liquid can be easily applied to a substrate. The alcohol is preferably ethanol, methanol, isopropyl alcohol, or the like, and ethanol is more preferable from the viewpoint of safety. The content of the alcohol is preferably 1 to 95% by mass, more preferably 5 to 93% by mass, and still more preferably 10 to 90% by mass, based on the total mass of the dispersion.
The content of the photocatalyst particles contained in the dispersion is preferably set to 0.1 to 20% by mass based on the total mass of the dispersion from the viewpoint of ease of application.
As the coating method, any method such as spray coating, die coating, bar coating, spin coating, screen printing, or the like can be used. The coating may be performed continuously in a large area by a roll-to-roll method or a batch method.
After the coating, a part or all of the dispersion medium contained in the layer 21a is dried and removed as necessary. Examples of the drying method include warm air heating, infrared heating, hot plate heating, and microwave heating. Among them, infrared heating and warm air heating are preferable because they can be easily applied to the roll-to-roll method.
Thereafter, a dispersion containing the 2 nd photocatalyst particles 22 is applied to form a 2 nd photocatalyst particle layer 22a (fig. 2 (B)). The dispersion used may be arbitrarily selected from the materials and adjustment conditions described for the dispersion of the 1 st photocatalyst, except that the 2 nd photocatalyst having a larger average particle diameter than the 1 st photocatalyst is used as the photocatalyst particles. The average particle diameter of the 2 nd photocatalyst particles is preferably 40 to 500nm. The coating method and the drying condition may be arbitrarily selected from the above-described coating method and drying condition. However, when the 1 st photocatalyst particle layer is not completely dried to form the 2 nd photocatalyst particle layer, some mixing may occur at the interface therebetween, but the interface S may be the interface between the first photocatalyst particle layer and the second photocatalyst particle layer b And interface S t Less influence, at S b The 1 st photocatalyst particle is locally present in the vicinity of S t The 2 nd photocatalyst particles are locally present in the vicinity.
Further, if necessary, the dispersion medium is dried and removed, whereby the photocatalyst composite material 10 according to the embodiment can be obtained (fig. 2C).
In this way, the photocatalyst composite according to the embodiment can be obtained. The dispersion liquid containing the 2 nd photocatalyst particles may be applied, and after a part or all of the dispersion medium is dried and removed, the photocatalyst particles having a large average particle diameter may be further stacked.
Generally, when a mixed dispersion of large particles and small particles is applied, the small particles tend to concentrate near the interface opposite to the substrate-side interface, i.e., S, due to the influence of gravity and the influence of a liquid flow generated in the dispersion during drying t Nearby. Therefore, the structure is different from that of the photocatalyst particles according to the embodiment. Therefore, the photocatalyst according to the embodiment can be obtained by stacking small particles first and large particles secondAgent particles.
Before coating the 1 st photocatalyst, a base layer may be formed in advance. The underlayer may be formed by dispersing an inorganic oxide or the like which is a material of the underlayer in a dispersion medium, and then coating and drying the dispersion medium by the same method as described above.
The total weight of the 1 st photocatalyst particles deposited on the substrate is preferably less than the total weight of the 2 nd photocatalyst particles deposited on the substrate. Since the surface area of the particles is inversely proportional to the particle diameter, sufficient catalytic activity can be obtained even if the deposition amount of the 1 st photocatalyst particles is small. On the other hand, if the deposition amount of the 1 st photocatalyst particles is too large, the photocatalyst layer tends to be easily peeled off, the space between the particles becomes small, and the diffusion of the substance to be processed tends to be inhibited.
In addition, as for the 1 st photocatalyst particle, the 2 nd photocatalyst particle, and the underlayer material to be used, it is preferable to select a material having an appropriate Zeta potential. By selecting particles having different Zeta potentials for the 1 st photocatalyst particle and the 2 nd photocatalyst particle and selecting materials having different Zeta potentials for the base layer material and the 1 st photocatalyst particle, the stability of the photocatalyst layer can be improved.
(embodiment 3)
Fig. 3 is a schematic diagram showing an example of the configuration of the photocatalyst apparatus according to embodiment 3.
As shown in the drawing, the photocatalyst apparatus 30 according to the embodiment includes the photocatalyst composite material 31 according to embodiment 1, a light irradiation member 32 for generating photocatalytic activity to a base material, and a supply member 33 for supplying a substance to the photocatalyst composite material. A chamber 34 in which these members are built may be further provided. Further, an introduction portion 35a for introducing a substance to be processed or a discharge port 35b for discharging the processed substance may be provided.
Among them, the substance to be treated is a substance which is intended to be changed by a chemical reaction promoted by the photocatalytic action of the photocatalyst composite material. Specifically, there are gases containing toxic components for which removal of harmful components is desired, gases containing odors for which deodorization is desired, waste liquids containing pollutants, and the like.
As the light irradiation member, there are a case of an optical system member that induces light to the photocatalyst composite material by outside light or indoor light, a case of a light source such as a lamp or an LED, and the like. In the case of using external light or indoor light, the photocatalyst composite may be provided or moved to a position where the photocatalyst composite is likely to receive light. When a light source is used, an LED is preferable from the viewpoint of low power consumption and downsizing.
The member for supplying the substance to the photocatalyst composite material is a gas, and examples thereof include a fan and a pump. In addition, when a gas or a liquid is introduced into a chamber in which the photocatalyst composite is built, the chamber and a nozzle for introducing the gas or the liquid into the chamber are also supply means. Further, the gas or liquid may be naturally diffused in the chamber, but convection generated by a heater or the like may be used. In this case, the heater is also the supply member. Further, in the case of utilizing natural diffusion, the photocatalyst composite may be provided or moved to a position where the photocatalyst composite is likely to come into contact with a substance.
When the photocatalyst composite is in the form of a plate, a substance to be treated can be made to flow along the surface thereof. In addition, when the photocatalyst composite is a porous body and the substance is a substance that can pass through the porous body, the contact area between the substance and the catalyst is increased, and therefore, the treatment efficiency is preferably increased. In addition, even when a substance to be treated flows along the surface of the photocatalyst composite, the contact area becomes large if the photocatalyst composite is porous. Therefore, the photocatalyst composite material is preferably a porous body, and more preferably in a cloth shape.
In this embodiment, the photocatalyst layer may further contain an adsorbent for adsorbing a substance. When such an adsorbent is contained in the photocatalyst, the efficiency of the catalytic action can be improved by increasing the concentration of the substance in the vicinity of the catalyst. Examples of such an adsorbent include activated carbon, alumina, zeolite, and silica gel.
Examples
(example 1)
A glass plate (10 cm. Times.10 cm) having a thickness of 1mm was rubbed on its surface with #40 sandpaper, washed with isopropyl alcohol, and then washed with pure water. The arithmetic average roughness of the surface was 4 μm. 1g of a fibrous alumina hydrate dispersion having an average diameter of 4nm and an average length of 1 μm in an amount of 0.5 mass% was dropped thereon, developed over the entire surface, and then dried at room temperature for 1 hour to form a foundation layer.
Subsequently, 1g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 20nm was dropped and developed over the entire surface, followed by drying at 60 ℃ for 1 hour. Subsequently, 4g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 100nm was dropped, developed over the entire surface, and then dried at 60 ℃ for 1 hour to obtain a photocatalyst composite material.
(photocatalytic Activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after 15 minutes of irradiation with a 6000lux fluorescent lamp, and the concentration after the same time was 10ppm in the case of using a light-shielded sample, relative to the initial concentration of 10ppm.
In the Escherichia coli antibacterial test, the initial bacteria concentration is 1 × 10 5 The number of bacteria per ml after 2 hours of light irradiation with a fluorescent lamp was 0. When a light-shielded sample was used, the number of bacteria after the same time was 1X 10 3 /ml。
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
(Peel resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. No peeling was seen, and the photocatalytic activity was hardly changed.
(example 2)
A surface of a 150 μm thick PET film (10 cm. Times.10 cm) was treated with UV ozone, 1g of a fibrous alumina hydrate dispersion liquid 0.5 mass% having an average diameter of 4nm and an average length of 1 μm was dropped, developed over the entire surface, and then dried at room temperature for 1 hour to form a base layer.
Subsequently, 1g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 20nm was dropped and developed over the entire surface, followed by drying at 60 ℃ for 1 hour. Subsequently, 4g of a 10% aqueous dispersion of fine particles of anatase titanium oxide having an average particle diameter of 100nm was added dropwise thereto, and the mixture was spread over the entire surface and dried at 60 ℃ for 1 hour to form a photocatalyst composite.
(photocatalytic Activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after irradiating with an LED having a center wavelength of 395nm for 13 minutes with light relative to the initial concentration of 10ppm. When the light-shielded sample was used, the concentration after the same time was 10ppm.
In the Escherichia coli antibacterial test, the initial bacteria concentration is 1 × 10 5 The number of bacteria per ml after 2 hours of irradiation with LED light was 0. When a light-shielded sample was used, the number of bacteria after the same time was 1X 10 3 /ml。
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
(peeling resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. No peeling was seen, and the photocatalytic activity was hardly changed.
(example 3)
A photocatalyst composite material was formed in the same manner as in example 2, except that a melamine resin film (10 cm × 10 cm) formed on an aluminum plate was used without treatment and without forming an undercoat layer, instead of the PET film.
(photocatalytic Activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after 20 minutes of LED light irradiation, relative to the initial concentration of 10ppm. When the light-shielded sample was used, the concentration after the same time was 10ppm.
In the Escherichia coli antibacterial test, the initial bacteria concentration is 1 × 10 5 The number of bacteria per ml after 2 hours of irradiation with LED light was 0. In the case of using a light-shielded sample, the number of bacteria after the same time periodIs 2 x 10 3 /ml。
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
(Peel resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. No peeling was observed, and the photocatalytic activity was hardly changed.
(example 4)
A photocatalyst composite material was obtained in the same manner as in example 1, except that copper oxide nanoparticles having an average particle diameter of 20nm were added to the coating solution in an amount of 0.05% by mass as a co-catalyst.
(photocatalytic activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after 12 minutes of irradiation with fluorescent light, relative to the initial concentration of 10ppm. When the light-shielded sample was used, the concentration after the same time was 10ppm.
In the Escherichia coli antibacterial test, the initial bacteria concentration is 1 × 10 5 The number of bacteria per ml was 0 after 1.5 hours of light irradiation with a fluorescent lamp. When a light-shielded sample was used, the number of bacteria after the same time was 1X 10 3 /ml。
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
(Peel resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. No peeling was seen, and the photocatalytic activity was hardly changed.
(example 5)
The surface of an aluminum plate (10 cm. Times.10 cm) having a thickness of 1mm was rubbed with #100 sandpaper, washed with isopropyl alcohol, and then washed with pure water. The arithmetic mean roughness of the surface was 1 μm.
Subsequently, 1g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 20nm was dropped and developed over the entire surface, followed by drying at 60 ℃ for 1 hour. Subsequently, 4g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 100nm was added dropwise thereto, and the mixture was developed over the entire surface and dried at 60 ℃ for 1 hour. Followed by heating at 600 ℃ for 3 hours in the atmosphere to obtain a photocatalyst composite.
(photocatalytic activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after 12 minutes of irradiation with a 6000lux fluorescent lamp, and the concentration after the same time was 10ppm in the case of using a light-shielded sample, relative to the initial concentration of 10ppm.
In the Escherichia coli antibacterial test, the initial bacteria concentration is 1 × 10 5 The number of bacteria per ml after 1.5 hours of light irradiation with a fluorescent lamp was 0. When a light-shielded sample was used, the number of bacteria after the same time was 1X 10 3 /ml。
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
(Peel resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. No peeling was observed, and the photocatalytic activity was hardly changed.
(example 6)
A photocatalyst apparatus having the photocatalyst composite obtained in example 2, 395nm LED and a small fan was set in a refrigerator. The power supply and the control device are arranged outside the refrigerator.
(Activity test of photocatalyst apparatus)
While the photocatalyst device was driven by emitting light from the LED, the initial concentration of methyl mercaptan of 10ppm was 0 after 30 minutes.
The photocatalytic activity was hardly changed even after 300 hours of light irradiation.
Comparative example 1
The surface of a glass plate (10 cm. Times.10 cm) having a thickness of 1mm was rubbed with #40 sandpaper, washed with isopropyl alcohol, and then washed with pure water. The arithmetic mean roughness of the surface was 4 μm. 1g of a fibrous alumina hydrate dispersion having an average diameter of 4nm and an average length of 1 μm in an amount of 0.5 mass% was dropped thereon, developed over the entire surface, and then dried at room temperature for 1 hour to form a foundation layer.
Subsequently, 5g of a 10% aqueous dispersion of tungsten oxide fine particles having an average particle diameter of 20nm was dropped and developed over the entire surface, and then dried at 60 ℃ for 1 hour to form a photocatalyst composite material.
(photocatalytic activity test)
In the acetaldehyde decomposition test, the concentration was 0ppm after 20 minutes of irradiation with a 6000lux fluorescent lamp, relative to 10ppm of the initial concentration. When the light-shielded sample was used, the concentration after the same time was 10ppm.
(Peel resistance test)
The photocatalyst was allowed to stand in water at 30 ℃ for 1 day. The photocatalyst particles were separated from the solution, and the photocatalytic activity was also decreased.
As is apparent from the results of the above examples, according to the embodiments, a photocatalyst composite having excellent catalytic activity, a method for producing the same, and a photocatalyst apparatus including the photocatalyst composite can be provided.
[ solution 1]
A photocatalyst composite material comprising a base material and a photocatalyst layer containing photocatalyst particles, wherein the substrate-side interface of the photocatalyst layer is S b Setting the opposite side interface as S t While the above S b The average particle diameter r of the photocatalyst particles in the vicinity b Less than S t The average particle diameter r of the photocatalyst particles in the vicinity t
[ solution 2]
The photocatalyst composite according to claim 1, wherein the particle size distribution curve of all the photocatalyst particles contained in the photocatalyst layer has two or more peaks.
[ solution 3]
The photocatalyst composite material according to claim 1 or 2, wherein r is as defined above b 2 to 50nm, above r t Is 40-500 nm.
[ solution 4]
The photocatalyst composite according to any one of claims 1 to 3, wherein the photocatalyst particles contain a metal oxide selected from the group consisting of tungsten oxide, titanium oxide, zinc oxide, niobium oxide, and tin oxide.
[ solution 5]
The photocatalyst composite material according to any one of claims 1 to 4, wherein the photocatalyst layer contains 20 to 100 mass% of the photocatalyst particles based on the total mass of the photocatalyst layer.
[ solution 6]
The photocatalyst composite material according to any one of claims 1 to 5, wherein the photocatalyst layer further contains a promoter containing a compound of a metal element, and the content of the metal element is 0.01 to 50% by mass relative to the total amount of the photocatalyst particles and the promoter particles.
[ solution 7]
The photocatalyst composite material according to any one of claims 1 to 6, wherein the photocatalyst layer further contains 1/100000 to 1/10 times as many silver nanowires as the total mass of the photocatalyst particles.
[ solution 8]
The photocatalyst composite according to any one of claims 1 to 7, further comprising a base layer between the base material and the photocatalyst layer.
[ solution 9]
The photocatalyst composite according to any one of claims 1 to 8, wherein the base layer contains an inorganic oxide.
[ solution 10]
The photocatalyst composite described in any one of claims 1 to 9, wherein the arithmetic average roughness of the surface of the base material is 0.2 to 20 μm.
[ solution 11]
The photocatalyst composite according to any one of claims 1 to 10, wherein the photocatalyst layer contains photocatalyst particles having different chemical compositions.
[ solution 12]
A method for producing a photocatalyst composite material, comprising the steps of: a step of coating a dispersion liquid containing the 1 st photocatalyst particles on a substrate; and applying a dispersion containing 2 nd photocatalyst particles having an average particle diameter larger than that of the 1 st photocatalyst particles.
[ solution 13]
The method of manufacturing a photocatalyst composite material according to claim 12, wherein the total weight of the 1 st photocatalyst particle deposited on the substrate is smaller than the total weight of the 2 nd photocatalyst particle deposited on the substrate.
[ solution 14]
The method of manufacturing a photocatalyst composite material according to claim 12 or 13, wherein the Zeta potential of the 1 st photocatalyst particle measured in water at pH6 and the Zeta potential of the 2 nd photocatalyst particle measured in the same manner have different signs.
[ solution 15]
The method for producing a photocatalyst composite material according to any one of claims 12 to 14, further comprising a step of forming a base layer on the base material before applying the dispersion liquid containing the 1 st photocatalyst particles, wherein a Zeta potential measured in water at pH6 of a material constituting the base layer has a sign different from a Zeta potential of the 1 st photocatalyst particles measured in the same manner.
[ solution 16]
A photocatalyst device comprising:
the photocatalyst composite material described in any one of claims 1 to 11,
A light irradiation member for generating photocatalytic activity on the substrate, and
a supply member for supplying a substance to be treated to the photocatalyst composite material,
the photocatalyst composite material having catalytic activity by the light promotes chemical reactions for treating the substance.
[ solution 17]
The photocatalyst apparatus according to claim 16, wherein the light irradiation member is an LED.
[ solution 18]
The photocatalyst apparatus according to claim 16 or 17, wherein the supply member is a fan.
[ solution 19]
The photocatalyst apparatus according to any one of claims 16 to 18, wherein the substance is supplied to a front surface of the photocatalyst composite material, and a product generated by the chemical reaction is discharged from a back surface of the photocatalyst composite material.
[ solution 20]
The photocatalyst apparatus according to any one of claims 16 to 19, wherein the photocatalyst layer further contains an adsorbent that adsorbs the substance.
It should be noted that several embodiments of the present invention have been described, but these embodiments are provided as examples and are not intended to limit the scope of the invention. These new embodiments may be implemented in other various ways, and various omissions, substitutions, and changes may be made without departing from the spirit of the invention. These embodiments and modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

Claims (8)

1. A photocatalyst composite material comprising a base material and a photocatalyst layer containing photocatalyst particles, wherein S is the interface on the base material side of the photocatalyst layer b Setting the opposite side interface as S t When is, the S b The average particle diameter r of the photocatalyst particles in the vicinity b Less than S t The average particle diameter r of the photocatalyst particles in the vicinity t
R is b Is 2 to 50nm, said r t Is 40 to 500nm, and the particle size is,
the arithmetic average roughness of the surface of the base material is 0.2 to 20 [ mu ] m.
2. The photocatalyst composite of claim 1, wherein the particle size distribution curve of all photocatalyst particles contained in the photocatalyst layer has two or more peaks.
3. The photocatalyst composite of claim 1 or 2, wherein the photocatalyst particles comprise a metal oxide selected from the group consisting of tungsten oxide, titanium oxide, zinc oxide, niobium oxide, and tin oxide.
4. The photocatalyst composite according to claim 1 or 2, wherein the photocatalyst layer further comprises 1/100000 to 1/10 times of silver nanowires, based on the total mass of photocatalyst particles.
5. The photocatalyst composite of claim 1 or 2, wherein the photocatalyst layer comprises photocatalyst particles that differ in chemical composition.
6. A method for producing a photocatalyst composite material, comprising the following steps in this order: a step of coating a dispersion liquid containing the 1 st photocatalyst particles on a substrate; a step of applying a dispersion liquid containing 2 nd photocatalyst particles having an average particle diameter larger than that of the 1 st photocatalyst particles,
the 1 st photocatalyst particle has an average particle diameter of 2 to 50nm, the 2 nd photocatalyst particle has an average particle diameter of 40 to 500nm,
the arithmetic average roughness of the surface of the base material is 0.2 to 20 [ mu ] m.
7. A photocatalyst device is provided with:
the photocatalyst composite described in any one of claims 1 to 5,
A light irradiation member for imparting photocatalytic activity to the substrate, and
a supply member that supplies a substance to be treated to the photocatalyst composite,
the photocatalyst composite that produces catalytic activity by light promotes chemical reactions for treating the substance.
8. The photocatalyst apparatus of claim 7, wherein the photocatalyst layer further comprises an adsorbing material that adsorbs the substance.
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KR102578848B1 (en) * 2020-11-25 2023-09-14 (주)웨이투메이크 Method for producing coating film using titanium dioxide photocatalyst composition
JP7436992B2 (en) * 2021-11-03 2024-02-22 アンデス電気株式会社 Photocatalytic antibacterial deodorizing material, its manufacturing method, antibacterial deodorizing material, and antibacterial deodorizing filter

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002200407A (en) * 2000-12-28 2002-07-16 Mitsubishi Plastics Ind Ltd Photocatalytic base material and filter using the same
CN1443605A (en) * 1993-12-10 2003-09-24 东陶机器株式会社 Multifunctional material with optical catalytic function and its mfg. method
JP2004002856A (en) * 2003-05-12 2004-01-08 National Institute Of Advanced Industrial & Technology Method for production of photocatalyst coating composition
JP2006150210A (en) * 2004-11-29 2006-06-15 Mitsubishi Paper Mills Ltd Manufacturing method of photocatalyst sheet
CN101795767A (en) * 2007-09-05 2010-08-04 株式会社东芝 Visible-light-responsive photocatalyst powder and used visible-light-responsive photocatalyst material, photocatalyst coating and the photochemical catalyst product of this powder
WO2011040406A1 (en) * 2009-09-30 2011-04-07 Toto株式会社 Photocatalyst-coated object and photocatalyst coating liquid therefor
CN102574120A (en) * 2009-09-30 2012-07-11 Toto株式会社 Photocatalyst-coated object and photocatalyst coating liquid therefor
CN105451882A (en) * 2013-03-12 2016-03-30 株式会社东芝 Photocatalyst and photocatalyst dispersion using same, photocatalyst coating, photocatalyst film, and product

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6217732B1 (en) * 1997-09-23 2001-04-17 Abb Business Services Inc. Coated products
JP2006255529A (en) * 2005-03-15 2006-09-28 Seiwa Kogyo Kk Photocatalyst filter, photocatalyst filter unit, clean room, air purifier, manufacturing apparatus and air purifying method
JP2007144403A (en) * 2005-10-27 2007-06-14 Atomix Co Ltd Composite type particulate photocatalyst, method for manufacturing the same and coating agent and photocatalytically-active member using the same
JP5395253B2 (en) * 2010-03-17 2014-01-22 株式会社オー・ティー・エー Photocatalytic filter
JP5708805B2 (en) * 2011-07-08 2015-04-30 日産自動車株式会社 Hydrophilic member and method for producing the same
CN103035410B (en) * 2011-10-08 2018-02-06 中国科学院上海硅酸盐研究所 Dye sensitized optoelectronic converting device and its manufacture method, and metal oxide paste
WO2013179681A1 (en) * 2012-06-01 2013-12-05 株式会社 東芝 Aqueous dispersion, and coating using same, photocatalytic film, and product
US10549268B2 (en) * 2013-07-05 2020-02-04 Nitto Denko Corporation Filter element for decomposing contaminants, system for decomposing contaminants and method using the system
CN103289453B (en) * 2013-07-08 2015-03-18 华夏贝能(北京)生态科技有限公司 Anti-bacteria deodorizing inorganic functional coating and preparation method thereof
US9833776B2 (en) * 2013-10-16 2017-12-05 Shin-Etsu Chemical Co., Ltd. Dispersion liquid of titanium oxide-tungsten oxide composite photocatalytic fine particles, production method for same, and member having photocatalytic thin film on surface thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1443605A (en) * 1993-12-10 2003-09-24 东陶机器株式会社 Multifunctional material with optical catalytic function and its mfg. method
JP2002200407A (en) * 2000-12-28 2002-07-16 Mitsubishi Plastics Ind Ltd Photocatalytic base material and filter using the same
JP2004002856A (en) * 2003-05-12 2004-01-08 National Institute Of Advanced Industrial & Technology Method for production of photocatalyst coating composition
JP2006150210A (en) * 2004-11-29 2006-06-15 Mitsubishi Paper Mills Ltd Manufacturing method of photocatalyst sheet
CN101795767A (en) * 2007-09-05 2010-08-04 株式会社东芝 Visible-light-responsive photocatalyst powder and used visible-light-responsive photocatalyst material, photocatalyst coating and the photochemical catalyst product of this powder
WO2011040406A1 (en) * 2009-09-30 2011-04-07 Toto株式会社 Photocatalyst-coated object and photocatalyst coating liquid therefor
CN102574120A (en) * 2009-09-30 2012-07-11 Toto株式会社 Photocatalyst-coated object and photocatalyst coating liquid therefor
CN105451882A (en) * 2013-03-12 2016-03-30 株式会社东芝 Photocatalyst and photocatalyst dispersion using same, photocatalyst coating, photocatalyst film, and product

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
JAE-HUN YANG: "TiO2 thin-films on polymer substrates and their photocatalytic activity", 《THIN SOLID FILMS》, vol. 495 *
QINGLONG ZENG: "Enhanced photocatalytic performance of Ag@TiO2 for the gaseous acetaldehyde photodegradation under fluorescent lamp", 《CHEMICAL ENGINEERING JOURNAL》, vol. 341 *
蒋鑫: "二氧化钛表面改性及其涂布膜光催化性能的研究", 《人工晶体学报》, vol. 46, no. 4 *

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