KR101684078B1 - Photocatalyst having high photocatalytic activity in visible range and manufacturing method of the same - Google Patents

Abstract

The present invention relates to a photocatalyst having high visible light activity and a method for producing the same, and the photocatalyst according to the present invention includes a polymer matrix having a high specific surface area of a porous structure and an inorganic component doped with a metal having high photoactivity, Adsorption and decomposition of substances and the like can be performed at the same time, thereby enabling continuous use, and high visible light activity can be realized.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocatalyst having high visible light activity and a method for producing the photocatalyst,

The present invention relates to a photocatalyst having high visible light activity and a method for producing the same.

When a photocatalyst receives light with energy above the bandgap energy, it excites electrons from the valence band to the conduction band, forming electrons in the conduction band, forming holes in the valence band, Diffuses to the surface of the photocatalyst and participates in oxidation and reduction reactions.

Photocatalysis can be used to produce hydrogen, a next generation alternative energy, by directly photodissolving water using solar energy. It can be used for decomposition of volatile organic compounds (VOCs), various odors, wastewater, , Sterilization of bacteria, bacteria and the like. Therefore, photocatalyst technology using only solar energy at room temperature is attracting attention as a powerful means to solve environmental problems by being applied to hydrogen production and environmental purification.

Titanium dioxide (TiO ₂ ), widely used as a photocatalyst at present, exhibits excellent properties in decomposing organic matter and water. However, titanium dioxide (TiO ₂ ) causes a photocatalytic reaction only in the ultraviolet region including about 4% of the sunlight.

Therefore, in order to utilize the photocatalyst technology effectively, it is necessary to develop a photocatalyst material having high visible light activity, which can effectively utilize visible light, which accounts for about 43% of the sunlight.

Korean Patent Publication No. 2014-0027591

An object of the present invention is to provide a photocatalyst having high visible light activity and a method for producing the same.

The present invention relates to a photocatalyst having high visible light activity and a method for producing the same, and as one example of the photocatalyst,

Polymer matrix of porous structure;

It is possible to provide a photocatalyst which is dispersed in a polymer matrix and contains an inorganic component doped with a metal and has a light absorption of 50% or more in a wavelength range of 400 to 700 nm.

Further, as one example of the method for producing the photocatalyst,

Activating the surface of the polymer matrix resin;

Dispersing the inorganic component precursor in the surface-activated polymer matrix; And

And a step of doping the metal precursor with the polymer matrix in which the inorganic component precursor is dispersed.

The photocatalyst according to the present invention is a porous structure comprising a polymer matrix having a high specific surface area and an inorganic component doped with a metal having a high optical activity and can be continuously used by performing simultaneous adsorption and decomposition of harmful substances, High visible light activity can be realized.

1 is a SEM photograph of an activated polyurethane matrix (PU), (B) an SEM photograph of a photocatalyst (TiO ₂ / PU) in which titanium dioxide is dispersed in an activated polyurethane matrix, (C) SEM photographs of a photocatalyst (Ag-TiO ₂ / PU) in which titanium dioxide doped with silver is dispersed in a urethane matrix and SEM photographs of some areas of (D) and (C).
FIG. 2 shows the results of high-resolution X-ray photoelectron spectroscopy (XRD) spectroscopy of Ag 3d peaks of a photocatalyst (Ag-TiO ₂ / PU).
FIG. 3 shows the high resolution X-ray photoelectron spectroscopy (SEM) spectra of Si 2p peaks of silicon in photocatalyst (TiO ₂ / PU) and photocatalyst (Ag-TiO ₂ / PU).
4 is a schematic diagram showing the surface chemical composition of TiO ₂ / PU (comparative example) and Ag-TiO ₂ / PU (example).
5 is a graph showing the relationship between the photocatalyst (PU, (a)) and the photocatalyst (Ag-TiO ₂ / PU, (c)) and the photocatalyst (TiO ₂ / PU, UV-Vis absorption spectra in the wavelength range.
6 is about the conditions (A) to (F) the polyurethane matrix (PU) and the photocatalyst (Ag-TiO ₂ / PU) and a photocatalyst produced in Comparative Example (TiO ₂ / PU) in e. This is the result of measuring the removal capacity for the E. coli supply.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail.

It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the present invention, the terms "comprising" or "having ", and the like, specify that the presence of a feature, a number, a step, an operation, an element, a component, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

Hereinafter, the present invention will be described in detail with reference to the drawings, and the same or corresponding components are denoted by the same reference numerals regardless of the reference numerals, and a duplicate description thereof will be omitted.

The present invention relates to a photocatalyst having high visible light activity and a method for producing the same, and as one example of the photocatalyst,

Polymer matrix of porous structure;

It is possible to provide a photocatalyst which is dispersed in a polymer matrix and contains an inorganic component doped with a metal and has a light absorption of 50% or more in a wavelength range of 400 to 700 nm.

Specifically, in the photocatalyst, the porous structure may have a structure having a pore pattern, and may have, for example, a honeycomb structure and a lattice structure. The polymer matrix of the porous structure and the inorganic component doped with the metal may be chemically bonded. For example, by activating the surface of the polymer matrix and imparting functional groups to the inorganic components using a binder, the functional groups of the activated polymer matrix surface and the inorganic components can be chemically bonded. The polymer matrix and the inorganic component form a photocatalyst through chemical bonding, so that excellent durability and visible light can be realized. Specifically, the photocatalyst can be easily reused continuously due to excellent durability, and visible light activity, which can account for about 43% of the existing sunlight, can be effectively used and utilized indoors.

At this time, the visible light activity effect of the catalyst can be confirmed by the light absorption in the wavelength range of 400 to 700 nm. Specifically, the light absorption of the photocatalyst according to the present invention in the wavelength range of 400 to 700 nm may be in the range of 50 to 80% or 50 to 70%.

The average particle size of the pores formed in the polymer matrix may be 50 to 500 μm and the average volume of the pores may be 0.01 to 0.03 cm ³ / g. For example, the average particle size of the pores may be from 50 to 400 μm or from 100 to 300 μm, and the average volume of the pores may range from 0.015 to 0.025 cm ³ / g or from 0.016 to 0.02 cm ³ / g. The polymer matrix having pores having an average particle size and an average volume within the above range can realize a high specific surface area.

The BET specific surface area of the photocatalyst may be 100 to 500 m ² / g. At this time, the BET specific surface area of the photocatalyst may mean a capacity at which harmful substances can be adsorbed. For example, the specific surface area of the photocatalyst may be 100 to 480 m ² / g, 100 to 400 m ² / g, or 150 to 250 m ² / g. When the specific surface area of the polymer matrix satisfies the above range, excellent adsorption ability can be realized due to a wide specific surface area.

The band gap of the photocatalyst may be 4 eV or less. For example, the band gap of the photocatalyst may range from 0.1 to 4 eV, from 1 to 4 eV, or from 2 to 3.5 eV. Generally, a photocatalyst can receive a light having an energy equal to or greater than a bandgap energy to perform a photoexcitation reaction. Specifically, the photoexcitation reaction may mean that electrons are excited from the valence band to the conduction band to form electrons in the conduction band and to form holes in the valence band. At this time, the formed electrons and holes diffuse to the surface of the photocatalyst and participate in the oxidation and reduction reaction, so that harmful substances can be decomposed.

Since the photocatalyst according to the present invention can perform the photoexcitation reaction even in the ultraviolet ray and visible ray region by adjusting the band gap to the above range, excellent photocatalytic efficiency can be expected in various optical environments.

Hereinafter, the polymer matrix, the inorganic component and the metal constituting the photocatalyst will be described.

The polymer matrix may include at least one of a polyurethane resin, a polyester resin and a polyamide resin. For example, the polymer matrix resin has a porous structure, has excellent porosity, and can exhibit excellent adsorbing ability against harmful substances according to excellent porosity. Specifically, the polymer matrix may be a polyurethane resin having a porous structure.

The inorganic component may include at least one of silica, titanium dioxide, and silver oxide. For example, the inorganic component has a low band gap, exhibits excellent characteristics in decomposing harmful substances, and may be an inorganic component having a pore structure having a wide specific surface area. Specifically, the inorganic component may be titanium dioxide.

The metal may be a transition metal. For example, the transition metal may be at least one selected from the group consisting of Ti, Zn, Al, Sc, Cr, Mn, Fe, Co, Ni, Cu, In, Sn, Y, Zr, Nb, Mo, Tc, Ru, Rh, Sr, W and Cd, and the like. Specifically, the metal may be silver (Ag).

Since the metal can induce the change of the band gap energy of the inorganic component and can perform the photoexcitation reaction not only in ultraviolet ray but also in sunlight in the visible light region, excellent photocatalytic efficiency can be expected in various optical environments.

The polymer matrix may include 80 to 95 parts by weight based on 100 parts by weight of the photocatalyst. For example, the content of the polymer matrix may be 85 to 95 parts by weight or 90 to 95 parts by weight. By including the polymer matrix in the above range, the photocatalyst can exhibit excellent adsorptivity according to a wide specific surface area and exhibit excellent durability.

The inorganic component may include 1 to 10 parts by weight based on 100 parts by weight of the photocatalyst. For example, the content of the inorganic component may be 3 to 10 parts by weight or 5 to 10 parts by weight. Since the photocatalyst contains an inorganic component in the above-mentioned range, excellent optical activity can be realized.

The metal may include 1 to 10 parts by weight based on 100 parts by weight of the photocatalyst. For example, the content of the metal may be 1 to 8 parts by weight or 3 to 8 parts by weight. Since the photocatalyst contains a metal in the above-mentioned range, the photocatalytic efficiency can be expected by inducing a photoexcitation reaction not only in the ultraviolet but also in the sunlight in the visible light region by reducing the band gap.

The present invention can provide a method for producing the photocatalyst, and as one example,

Activating the surface of the polymer matrix resin;

Dispersing the inorganic component precursor in the surface-activated polymer matrix; And

And a step of doping the metal precursor with the polymer matrix in which the inorganic component precursor is dispersed.

For reference, the polymer matrix, inorganic component and metal may be the same as described above.

Hereinafter, the method for producing the photocatalyst according to the present invention will be described in more detail.

First, the step of activating the surface of the polymer matrix resin may be a step of activating an isocyanate group (NCO) on the surface of the polymer matrix resin. For example, an isocyanate group (NCO) can be activated on the surface of a polymer matrix resin by mixing a basic organic compound and a polyisocyanate compound with a polymer matrix resin.

The basic organic compound may include a tertiary amine such as trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tributylamine, diisopropylethylamine and triphenylamine have. Specifically, the basic organic compound may be triethylamine.

Examples of the polyisocyanate compound include, for example, toluene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, p Diisocyanate diisocyanate, diisocyanate diisocyanate, diisocyanate diisocyanate, diisocyanate diisocyanate diisocyanate, diisocyanate diisocyanate diisocyanate, diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate diisocyanate , Isophorone diisocyanate, 1,5-naphthalene diisocyanate, trans-1,4-cyclohexyl diisocyanate, lysine diisocyanate, dimethyltriphenylmethane tetraisocyanate, triphenylmethane triisocyanate, and tris (Isocyanatophenyl) thiophosphate and the like can be used. It can hamhal. Specifically, the polyisocyanate compound may be silver toluene diisocyanate.

Specifically, in the step of activating the surface of the polymer matrix resin, triethylamine takes up hydrogen in the polymer matrix resin, so that the urea bond is broken and the isocyanate bond is formed in the polymer matrix resin. The separated urea oxygen is dissolved in toluene Can be carried out by performing surface activation by attacking the diisocyanate to form a toluene derivative in which a new urea bond is formed. In this way, the isocyanate group (NCO) of the surface of the polyurethane resin can be activated.

Then, in the step of dispersing the inorganic component precursor in the surface-activated polymer matrix, the inorganic component precursor may further comprise a binder. The binder may include, for example, at least one of a silane-based binder, a titanate-based binder, a urea binder, an ionic binder, and a covalent binder.

The binder is mainly used for improving the tensile strength, bending strength, compressive strength and modulus of a composite material made of different materials. In some cases, the binder is used to strengthen bonding between different materials. In the present invention, the binder is used for improving the bonding force between the polymer matrix and the inorganic component, and specifically, a silane binder may be used. The silane coupling agent may be selected from, for example, tetramethoxy silane (TMOS), tetraethoxy silane (TEOS), tetrabutoxysilane (TBS), aminopropyltriethoxysilane -Aminopropyl triethoxy silane (APTES), and 3-aminopropyl trimethoxy silane (APTMS).

Specifically, the inorganic component precursor may be prepared by mixing a binder and an inorganic component. At this time, the functional group of the binder can be imparted to the inorganic component. For example, a silane-based titanium dioxide mixture can be prepared by mixing a silane-based binder with a titanium dioxide precursor. Thus, by dispersing the silanized titanium dioxide mixture on the surface of the isocyanate group-activated polyurethane resin, the amino group present in the silane coupling agent of the activated polyurethane resin and the silanized titanium dioxide is bonded to form a urea bond do.

At this time, depending on the case, the inorganic component precursor can be used by dispersing the binder and the inorganic component in a solvent. The solvent is not particularly limited and includes, for example, water, methanol, ethanol, propanol, toluene, chloroform, N, N-dimethylformamide, Tetrahydrofuran, benzene, and the like can be used. By dispersing using a solvent, high stability and durability can be ensured with high dispersibility.

In the step of doping the metal precursor with the polymer matrix in which the inorganic component precursor is dispersed, the metal precursor may be dispersed by mixing one or two or more kinds of them and using a solvent. For example, the metal precursor may be silver nitrate (AgNO ₃ ). The kind of the solvent used at this time may be the same as described above.

The method may further include a step of doping the polymer matrix in which the inorganic component precursor is dispersed, a step of drying at 50 to 80 ° C, and a step of calcining at 150 to 300 ° C for 1 to 3 hours. As a result, a photocatalyst in which an inorganic component doped with a metal is dispersed in a matrix can be produced.

Hereinafter, the present invention will be described in more detail with reference to Examples and Experimental Examples. However, the following Examples and Experimental Examples are merely illustrative of the present invention, and the present invention is not limited to the following Examples and Experimental Examples.

Example

(1) Production of polymer matrix resin

The isocyanate group of the polyurethane resin was activated by mixing trimethylamine and toluene-2,4-diisocyanate in the polyurethane resin. This can be confirmed through FIG. 1 (A). Specifically, Fig. 1 (A) is an SEM photograph of an activated polyurethane matrix (PU). As a result, a porous structure having an average particle size of about 100 to 300 mu m of the polyurethane matrix was confirmed.

(2) Production of inorganic precursor

Titanium isopropoxide (TTIP) and 3-aminopropyl triethoxysilane (APTES) were mixed to prepare a silanized titanosiloxane precursor, which is an inorganic precursor.

(3) Photocatalyst manufacture

The polyurethane matrix resin activated in (1) above is reacted with an isocyanate group in the polyurethane matrix, which is a precursor of the inorganic component silanized in (2), and then hydrated. Thus, a photocatalyst in which titanium dioxide is dispersed in the polyurethane matrix (TiO ₂ / PU). This can be confirmed from FIG. 1 (B). Specifically, FIG. 1 (B) is an SEM photograph of a photocatalyst (TiO ₂ / PU) in which titanium dioxide is dispersed in an activated polyurethane matrix. As a result, it was confirmed that titanium dioxide was uniformly dispersed on the surface of the polyurethane matrix.

Then, 0.1 mol of silver nitrate (AgNO ₃ ) was doped as a metal precursor to a photocatalyst in which titanium dioxide was dispersed in a polyurethane matrix, and the resultant was dried at 60 ° C and calcined at 200 ° C for 2 hours to obtain a polyurethane matrix A photocatalyst (Ag-TiO ₂ / PU) in which titanium dioxide doped with silver was dispersed was prepared. This can be confirmed through FIG. 1 (C). Specifically, FIG. 1C is a SEM photograph of a photocatalyst (Ag-TiO ₂ / PU) in which titanium dioxide doped with silver is dispersed in an activated polyurethane matrix. Through this, it was confirmed that the silver particles were uniformly doped on the titanium dioxide.

1 (D), it can be confirmed that silver (Ag) and titanium (Ti) are evenly doped and / or dispersed in Ag-TiO ₂ / PU. As a result, it was confirmed that titanium dioxide and silver were uniformly distributed on the polyurethane matrix.

Comparative Example

(3), a photocatalyst (TiO ₂ / PU) in which titanium dioxide was dispersed in a polyurethane matrix was prepared without separately doping the titanium dioxide.

Experimental Example  One: XPS (X- ray photoelectron spectroscopy ) Measure

(1) silver (Ag)

High resolution XPS spectra of Ag 3d peaks of the photocatalyst (Ag-TiO ₂ / PU) prepared in the above Example were measured. This is shown in FIG. Referring to FIG. 2, the state of the Ag Ag-TiO ₂ / PU is found to be ^o Ag and Ag ^+. The peaks observed at 374.1 and 368.1 eV represent specific peaks of metallic Ag (Ag ⁰ ). ^O Ag may be formed due to the light reduction and thermal decomposition occurring in the light emitting and calcination processes of AgNO _3. Also, the peaks observed at 373.3 and 367.3 eV represent specific peaks of Ag ⁺ . Ag ⁺ adsorbed on the TiO ₂ surface can be strongly adsorbed to the surface of TiO ₂ by Ti-O-Ag bonding through photoreduction. At this time, since considerably higher than the peak width and peak intensity of the Ag ^{+ o} Ag in the Ag-TiO ₂ / PU concentration of Ag ^o it can be seen that significantly higher than the Ag ^+.

(2) Silicon (Si)

A high-resolution X-ray photoelectron spectroscopy (XPS spectra) of Si 2p peaks of silicon in the photocatalyst (TiO ₂ / PU) and the photocatalyst (Ag-TiO ₂ / PU) This is shown in FIG. In the spectrum of the photocatalyst (TiO ₂ / PU) in FIG. 3, it was confirmed that there were three different peaks at 103.8, 102.7 and 101.9 eV. Each of the peaks represents the energy of Si-O-Si bond, Si-O-Ti bond and C-Si-O bond in Si 2p, respectively. The peak of the Si-O-Si bond means that SiO ₂ exists in TiO ₂ / PU. In addition, it can be seen that silicon through the peaks of Si-O-Ti bonds and C-Si-O bonds serves as a bridge in bonding the polyurethane matrix and TiO ₂ . Thus, for example, the surface chemistry of TiO ₂ / PU may comprise polyurethane matrices, SiO ₂ and TiO ₂ .

Further, the Si 2p X-ray photoelectron spectroscopy of the silicon in the photocatalyst (Ag-TiO ₂ / PU) prepared in the Examples showed three different peaks at 103.7, 102.4 and 101.9 eV. Each of the peaks represents the energy of Si-O-Si bond, Si-O-Ti bond and C-Si-O bond in Si 2p, respectively. At this time, peaks of Si-O-Si bond and Si-O-Ti bond were shifted to a binding energy region lower by about 0.1 and 0.3 eV, respectively, ). These results are shown by the dispersion of Ag particles on the TiO ₂ surface.

The electron clouds of silicon in Si-O-Si bonds and Si-O-Ti bonds can be increased by the plasmon resonance of Ag particles transferring each peak to a lower binding energy region. On the other hand, because the Ag particles are far away from the C-Si-O bond, the plasmon resonance of Ag is insufficient for increasing the electron cloud of silicon in the C-Si-O bond. And the peaks of the Si-O bonds are the same.

The surface chemical composition of the TiO ₂ / PU (comparative example) and Ag-TiO ₂ / PU (example) can be confirmed from FIG. Referring to FIG. 4, TiO ₂ is bonded to the polyurethane matrix (PU) via C-Si-O-Ti bonds.

Experimental Example  2: BET Specific surface area  Measure

BET specific surface area measurement was performed on the polyurethane matrix (PU), the photocatalyst (Ag-TiO ₂ / PU) and the photocatalyst (TiO ₂ / PU) The measurement method is described below, and the results are shown in Table 1 below.

* BET specific surface area measurement method: The BET specific surface area was measured using a nitrogen adsorption-desorption method.

PU Comparative Example (TiO ₂ / PU) Example (Ag-TiO ₂ / PU) BET specific surface area (m ² / g) 30.46 110.93 186.56

It can be seen from Table 1 that the Ag-TiO ₂ is dispersed on the PU surface of the porous structure, and the specific surface area is remarkably increased. This may mean that the photocatalytic performance is improved.

In particular, the specific surface area of the photocatalyst (Ag-TiO ₂ / PU) was significantly increased by about 6 times or more as compared with that of PU, and increased by about 1.7 times as compared with TiO ₂ / PU.

Thus, the increase of the specific surface area of the photocatalyst (Ag-TiO ₂ / PU) can be realized by effectively increasing the specific surface area of TiO ₂ through the C-Si-O-Ti bond between TiO ₂ and PU. Further, by doping Ag on the TiO ₂ phase, a further improved specific surface area could be realized.

Experimental Example  3: UV - Vis absorption spectra  Measure

(TiO ₂ / PU, (b)) prepared in the above example and the photocatalyst (Ag-TiO ₂ / PU, (c) UV-Vis absorption spectra were measured at wavelengths ranging from 700 nm to 700 nm. The results are shown in FIG. 5, the light absorption of the photocatalyst (b) produced in the comparative example starts to decrease in the wavelength range of 370 nm, the light absorption decreases to about 40% in the wavelength range of 400 nm, , It can be confirmed that it is reduced to 30% or less. On the contrary, it can be confirmed that the photocatalyst (c) according to the embodiment of the present invention maintains a light absorption of 50% or more in a wavelength range of 400 to 700 nm. These results are shown because of the light absorption characteristics of the Ag particles dispersed on the TiO ₂ surface. As a result, it can be seen that the light absorption in the visible light region is remarkably improved due to the Ag particles.

Experimental Example  4: E. coli  Removal experiment

Removal capacity of the polyurethane matrix (PU), the photocatalyst (Ag-TiO ₂ / PU), and the photocatalyst (TiO ₂ / PU) . The results are shown in FIG. 6 and Table 2, and the conditions (A) to (F) are as follows.

(A): PU was measured in a dark room condition

(B): a result of measurement on PU under visible light condition (vis-light: 0.025 W / cm ² ).

(C): Results of measurement in dark room conditions (dark) for TiO ₂ / PU.

(D): Measurement result of TiO ₂ / PU under visible light condition (vis-light: 0.025 W / cm ² ).

(E): Results of measurement in dark room conditions (dark) for Ag-TiO ₂ / PU.

(F): The result of measurement on Ag-TiO ₂ / PU under visible light condition (vis-light: 0.025 W / cm ² ).

PU Comparative Example (TiO2 / PU) Example (Ag-TiO2 / PU) Condition Dark
(A) Vis-light
(B) Dark
(C) Vis-light (D) Dark
(E) Vis-light (F) Maximum removal capacity (CFU / cm ³ ) 1.2 × 10 ⁵ 1.2 × 10 ⁵ 2.7 × 10 ⁵ 2.8 × 10 ⁵ 6.2 × 10 ⁵ 1.8 × 10 ⁶

First, referring to FIG. 6, when the E. coli was supplied in the range of 500 to 5 × 10 ⁷ CFU, the removal capacity in the conditions (A) to (F) was measured. (E) and (F) using the photocatalyst prepared in the example according to the present invention, (A), (B) and (C) To (D), a remarkably excellent removal capacity was obtained.

Also, referring to Table 2, the maximum removal capacity of E. coli can be confirmed under each condition.

Removal of E. coli in dark (dark) conditions is mainly due to adsorption of PU, TiO ₂ / PU and Ag-TiO ₂ / PU, respectively. The adsorption of E. coli is based on the interaction of the surface adsorptivity of the photocatalyst with the cell, including van der Waals, electrostatic and hydrophobic interactions. The interaction due to the adsorption of E. coli is affected by pore structure, specific surface area, roughness, surface charge, chemical structure, hydrophobicity and the like.

In visible light conditions (vis-lifgt), the maximum E. coli removal capacity of PU and TiO ₂ / PU is almost unchanged from the dark room conditions. However, the Ag-TiO ₂ / PU according to the present invention exhibits an excellent removal capacity of about three times or more as compared with the dark room conditions. It was confirmed that PU and TiO ₂ / PU can be removed only by adsorption under visible light conditions.

The removal capacity of Ag-TiO ₂ / PU in visible light (vis-lifgt) is possible because of the enhancement of the photocatalytic activity of Ag and the formation of paired pairs under visible light conditions. The formed paired hole pair may then react with water and oxygen molecules adsorbed on the photocatalyst surface to form an oxy radical such as a hydroxyl radical (-OH) and a superoxide radical anion (-O ₂ ^- ) . These oxy radicals have high reactivity and can participate in the oxidation process of decomposing organic components of bacteria to remove bacteria.

Claims (10)

A polymer matrix having a porous structure and having an isocyanate group on its surface; And
A silanized inorganic component dispersed in a polymer matrix and having an amine group,
Wherein the inorganic component is doped with a metal,
The isocyanate group on the surface of the polymer matrix and the amine group of the silanized inorganic component are urea bonded,
Has a light absorption of 50% or more in a wavelength range of 400 to 700 nm,
A photocatalyst having a BET specific surface area of 100 to 500 m ² / g.
The method according to claim 1,
And the average particle diameter of the pores is from 50 to 500 ㎛ formed in the polymer matrix, the average volume of the pores is a photocatalyst, characterized in that 0.01 to 0.03 cm ³ / g.
delete The method according to claim 1,
Wherein the photocatalyst has a band gap of 4 eV or less.
The method according to claim 1,
Wherein the polymer matrix comprises at least one of a polyurethane resin, a polyester resin and a polyamide resin.
The method according to claim 1,
Wherein the inorganic component comprises at least one of silica, titanium dioxide and silver oxide.
The method according to claim 1,
Wherein the metal is a transition metal.
Activating the surface of the polymer matrix resin;
Dispersing the inorganic component precursor in the surface-activated polymer matrix; And
A method for producing a photocatalyst according to claim 1, comprising the step of doping a metal precursor with a polymer matrix in which an inorganic component precursor is dispersed.
9. The method of claim 8,
Wherein the inorganic component precursor further comprises a binder in the step of dispersing the inorganic component precursor in the surface-activated polymer matrix.
10. The method of claim 9,
Wherein the binder comprises at least one of a silane-based binder, a titanate-based binder, a urea binder, an ionic binder and a covalent binder.

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