KR20170042999A - 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.

U.S. Published Patent Application No. 2007-0148424

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;

A polymer matrix and an inorganic component doped with a metal,

Based on 100 parts by weight of the polymer matrix, 0.1 to 15 parts by weight of a metal-doped inorganic component.

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).
2 is an SEM photograph of a photocatalyst (TiO ₂ / PU) in which titanium dioxide is dispersed in a polyurethane matrix and an SEM photograph of the photocatalyst (V-TiO ₂ / PU) prepared in Examples 1 to 5.
Figure 3 shows the result of measurement in Example 1 X-ray photoelectron spectrum of the resolution for the V 2p _3/2 peak of a photocatalyst (V-TiO ₂ / PU) produced from to 5 (high resolution XPS spectra).
4 is measurement results of Examples 1 to 5 and Comparative Examples a photocatalyst (V-TiO ₂ / PU) of the Ti 2p _3/2 X-ray photoelectron spectrum of the resolution for the peak (high resolution XPS spectra) prepared in to be.
FIG. 5 shows UV-Vis absorption spectra of the photocatalyst prepared in Examples 1 to 5 and Comparative Examples in a wavelength range of 300 to 700 nm.
FIG. 6 shows the results of measurement of toluene amount (C / Co) and CO ₂ concentration in the toluene amount / discharge gas in the injection gas over time for 0 to 330 seconds with respect to the photocatalyst prepared in Example 3. FIG.
FIG. 7 shows the results of measurement of removal rates and photodegradation rates of toluene by photocatalytic reaction under visible light conditions (vis-light: 0.025 W / cm ² ) for the photocatalysts prepared in Examples 1 to 5 and Comparative Examples.

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;

A polymer matrix and an inorganic component doped with a metal,

Based on 100 parts by weight of the polymer matrix, 1 to 10 parts by weight of a metal-doped inorganic component.

Specifically, the photocatalyst may have a porous structure having a pore pattern, for example, a honeycomb structure, a lattice structure, or the like. 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. By forming the photocatalyst through the chemical bond between the polymer matrix and the inorganic component, the microorganisms can be adsorbed to the porous structure of the polymer matrix, and the microorganisms can be decomposed through the photocatalyst to simultaneously perform adsorption and decomposition. In addition, the photocatalyst can realize excellent durability and visible light. 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.

This can be achieved by mixing a photocatalyst in which the metal-doped inorganic component is 0.1 to 15 parts by weight based on 100 parts by weight of the polymer matrix. For example, the metal-doped inorganic component may be 0.5 to 13 parts by weight, 1 to 10 parts by weight, 2 to 10 parts by weight, or 4 to 8 parts by weight based on 100 parts by weight of the polymer matrix.

The visible light activity effect of the photocatalyst can be confirmed through light absorption in a 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%. Accordingly, it can be seen that the photocatalyst according to the present invention can perform photo-excitation reaction not only in ultraviolet rays but also in sunlight in a visible light region, thereby realizing excellent photocatalytic efficiency under various optical environments.

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 120 to 500 m ² / g. This may be formed due to the structure of the porous polymer matrix, and the BET specific surface area of the photocatalyst may mean a capacity at which harmful substances or the like can be adsorbed. For example, the specific surface area of the photocatalyst may be 120 to 480 m ² / g, 120 to 400 m ² / g, or 130 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 bandgap of the photocatalyst may range from 0.1 to 4 eV, from 1 to 4 eV, or from 2.5 to 3.1 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 is to receive electrons from a valence band to a conduction band by receiving light from a region having a specific energy in incident light, thereby forming electrons in the conduction band and forming holes in the valence band can do. 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.

However, the conventional photocatalyst has a high bandgap between the valence band and the conduction band, so that only ultraviolet rays having strong energy can be used to cause a photoexcitation reaction therebetween.

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 selected from the group consisting of V, Ti, Zn, Al, Sc, Cr, Mn, Fe, Co, Ni, Cu, In, Sn, Y, Zr, Nb, Mo, Tc, Ag, Sr, W and Cd, and the like. Specifically, the metal may be vanadium (V).

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 polymer matrix resin with a compound containing a basic organic compound and a polyisocyanate.

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, an aminotitanosiloxane having an Si-O-Ti bond and an amino group (NH ₂ ) can be produced.

Then, the amino group of the amino titanosiloxane is chemically bonded to the activated isocyanate group on the surface of the polyurethane resin, and the amino titanosiloxane can be fixed on the surface of the polyurethane resin.

The inorganic component may include, for example, titanium isopropoxide (TTIP).

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 comprise ammonium metavanadate (NH ₄ VO ₃ ). The kind of the solvent used at this time may be the same as described above.

Further comprising the step of doping the polymer matrix in which the inorganic component precursor is dispersed with a metal precursor, followed by UV irradiation for 3 to 6 hours and calcination for 3 to 6 hours at 150 to 300 캜 in a nitrogen atmosphere can do. 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 to 5

(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 from FIG. Specifically, Figure 1 is a SEM image 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) Inorganic  Preparation of component precursor

Aminotitanosiloxane was prepared by mixing titanium isopropoxide (TTIP) and aminopropyl triethoxysilane (APTES).

(3) Photocatalyst  Produce

A photocatalyst (TiO ₂ / PU) in which titanium dioxide was dispersed in a polyurethane matrix was prepared by mixing the polyurethane matrix resin activated in (1) above and the amino titanosiloxane as an inorganic component precursor prepared in (2). This can be confirmed through A in FIG. Specifically, FIG. 2A is an SEM photograph of a photocatalyst (TiO ₂ / PU) in which titanium dioxide is dispersed in a polyurethane matrix.

Then, 0.1 mol ammonium metavanadate (NH ₄ VO ₃ ) was doped as a metal precursor to a photocatalyst in which titanium dioxide was dispersed in a polyurethane matrix, and the resultant was subjected to UV irradiation for 5 hours, To prepare a photocatalyst (V-TiO ₂ / PU) dispersed in vanadium-doped titanium dioxide in a polyurethane matrix.

At this time, the content of vanadium-doped titanium dioxide (V-TiO ₂ ) was adjusted as shown in the following Table 1 based on 100 parts by weight of the polyurethane matrix (PU) by controlling the content of the inorganic component precursor composition and the amount of ammonium metavanadate Respectively.

V-TiO ₂ (Parts by weight) Example 1 2 Example 2 4 Example 3 6 Example 4 8 Example 5 10

At this time, SEM photographs of the photocatalyst (V-TiO ₂ / PU) prepared in Examples 1 to 5 were photographed and are shown in FIGS. 2B to 2F. Specifically, the SEM of the photocatalyst prepared in Example 1 is shown in Fig. 2B, the SEM of the photocatalyst produced in Example 2 is shown in Fig. 2C, and the photocatalyst prepared in Example 3 is SEM 2 is shown in D of FIG. 2, the SEM of the photocatalyst prepared in Example 4 is shown in FIG. 2E, and the SEM of the photocatalyst prepared in Example 5 is shown in FIG. 2F.

As a result, it was confirmed that titanium dioxide and vanadium were almost evenly 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 vanadium.

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

(1) vanadium (V)

The above-described embodiment 1 X-ray photoelectron spectrum of the high resolution for a photocatalyst _{(V-TiO 2 / PU)} V 2p 3/2 peak of manufactured to 5 (high resolution XPS spectra) were measured. This is shown in FIG. Figure 3 In, V-TiO ₂ / of PU V 2p _3/2 denotes the two types of peaks at 516.0 and 517.4 eV, refers to the binding energy of the V 2p _3/2 In these V ^{4 +} and V ^{5 +} state do. The V ^{5 +} state in V-TiO ₂ / PU may correspond to the V ₂ O ₅ oxide state formed from the NH ₄ VO ₃ precursor in the manufacturing process. On the other hand, V ^{4 +} is formed when V ^{5 +} decreases. The reduction of V ^{5 +} can be caused by oxidation by oxylic acid due to the influence of temperature during UV irradiation and sintering. Since the V ^{4 +} (72 Å) is similar in diameter to Ti ^{4 +} (74 Å), it can be included in the TiO ₂ lattice by replacing the sites of Ti ^{4 +} ions in the Ti-OV bond. Thus, vanadium in the V-TiO ₂ / PU can be doped into the TiO ₂ lattice in the V ^{4 +} and V ^{5 +} states. In this case, the V-TiO ₂ / PU in a ^{4 +} V / ^{5 +} V ratio is proportional to the peak area V ⁴⁺ / V ^{5 +} peak area in the photoelectron spectrum shows an X-ray.

Referring to FIG. 3, V ^{4 +} / ^{5 +} V ratio may be found that, when gradually becomes closer to the stability of 6 parts by weight, and increased rapidly, V / TiO ₂ content as V / TiO ₂ content is increased.

(2) Titanium ( Ti )

The above Examples 1-5 and Comparative X-ray photoelectron spectrum of the high resolution for a photocatalyst (V-TiO ₂ / PU) of the Ti 2p _3/2 peak, prepared in example (high resolution XPS spectra) were measured. This is shown in FIG. Referring to FIG. 4, it can be seen that V-TiO ₂ / PU is formed containing both Ti ^{4 +} and Ti ^{3 +} . In the V-TiO ₂ / PU, the formation of Ti ^{3 +} may appear due to the doping effect of the V ^{+ 4.} At this time, V ^{4 +} shares titanium and oxygen atoms in the TiO ₂ lattice to form a Ti-OV bond, which causes oxygen vacancies in the lattice. TiO ₂ Oxygen in the lattice space is Ti ^{4 +} a The main reason for the decrease is the Ti ^{3 +.}

In the V-TiO ₂ / PU tends containing the Ti ^{3 +} is a time closer to the rapidly increasing, V / TiO 6 parts by weight of ₂ content as V / TiO ₂ content is increased, in the case of V ^{4 +} gradually stable with similar. The results show that TiO ₂ The inclusion of a certain amount of V ^{4 +} in the lattice can mean that it induces Ti ^{3 +} formation in the lattice.

The electron number of Ti ^{3 +} is 19, which is higher than the Ti ^{4 + of} 18. From this, it can be seen that Ti ^{3 +} is more easily excited than Ti ^{4 +} . Therefore, it can be seen that V-TiO ₂ / PU having a high Ti ^{3 +} / Ti ^{4 +} ratio can realize a high electron generation amount.

At this time, the V ^{4 +} / V ^{5 +} ratio and the Ti ^{3 +} / Ti ^{4 +} ratio measured in FIGS. 3 and 4 are shown in Table 2 below.

V ^{4 +} / V ^{5 +} ratio Ti ^{3 +} / Ti ^{4 +} ratio Example 1 15.5 12.3 Example 2 24.3 18.5 Example 3 35.4 30.1 Example 4 38.2 32.2 Example 5 40.8 33.6 Comparative Example - 0

Experimental Example  2: BET Specific surface area  And Band gap  Measure

To Example 1 from the photocatalyst prepared to _{5 (Ag-TiO 2 / PU} ) and Comparative Examples BET specific surface area and a band gap determined with respect to the prepared photocatalyst (TiO ₂ / PU) were carried out in the. The measurement method is described below, and the results are shown in Table 3 below.

1) BET Measurement of specific surface area : BET specific surface area was measured using a nitrogen adsorption-desorption method.

2) Method of measuring the bandgap : The Y-axis represents the square root of the value obtained by multiplying the energy value (E) for the wavelength by the energy value by the X-axis and the diffuse reflectance (R) by Kubelka-Munk In the Tauc plot shown, the straight line near the absorption edge was extended to measure the X axis.

BET specific surface area (m ² / g) Band gap (eV) Example 1 131.7 3.09 Example 2 156.3 2.93 Example 3 192.5 2.83 Example 4 186.7 2.76 Example 5 180.2 2.76 Comparative Example 110.9 3.20

Referring to Table 3, it can be seen that the BET specific surface area of the photocatalyst prepared in the example of the present invention is significantly higher than that of the comparative example, and in particular, the V / TiO ₂ content in V-TiO ₂ / In the case of Example 3 having 6 parts by weight, it was confirmed that the BET specific surface area was shown to be at most 192.5 m ² / g.

In addition, as compared with 3.2 eV of the photocatalyst prepared in the comparative example, the bandgap of the present invention decreases as the V / TiO ₂ content increases in V-TiO ₂ / PU.

Experimental Example  3: UV - Vis absorption spectra  Measure

UV-Vis absorption spectra were measured for the photocatalysts prepared in Examples 1 to 5 and Comparative Examples in the wavelength range of 300 to 700 nm. The results are shown in FIG. 5, it can be seen that the light absorbance decreases after 370 nm, which is the UV wavelength region. However, in the case of Examples 1 to 5 according to the present invention, in particular, in the case of the photocatalyst according to Example 3, it can be confirmed that the rate of decrease of the light absorption is remarkably reduced as compared with the comparative example.

These results are shown because of the light absorption characteristics of the V 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 V particle.

Experimental Example  4: Toluene removal experiment

The amount of toluene (C / Co) and the amount of CO _{2 in} the toluene amount / exhaust gas in the injection gas over time for 0 to 330 seconds with respect to the photocatalyst prepared in Example 3 . At this time, the dark state was performed for 150 seconds and the vis-light state (0.025 W / cm ² ) was performed for 150 seconds or more. The results are shown in FIG.

6, C / Co gradually increases to 150 seconds, and CO ₂ It can be confirmed that there is no change in the concentration. As a result, it can be seen that toluene is removed only by adsorption in the dark room condition. At this time, the adsorption of toluene is caused by a direct electrostatic interaction between an ion such as Ti ^{3 +} , Ti ^{4 +} , V ^{4 +,} and V ^{5 +} on the photocatalyst surface and an aromatic ring of toluene.

Further, in the visible light condition (vis-lifgt), CO ₂ This is because the photocatalytic function of the V doped in the photocatalyst according to the present invention is enhanced to form a paired pair 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 act as excellent oxidizing agents and can decompose toluene to CO ₂ and H ₂ O.

Thus, it can be seen that the photocatalyst according to the present invention can decompose toluene not only in the UV region but also in the visible region.

Experimental Example  5: Under visible light conditions Photocatalyst  Performance evaluation

Photocatalysts prepared in Examples 1 to 5 and Comparative Examples were measured for removal rate and photodegradation rate of toluene by photocatalytic reaction under visible light conditions (vis-light: 0.025 W / cm ² ). The results are shown in Table 7 below.

7, it can be seen that in the case of the comparative example in which vanadium is not doped, toluene is hardly removed under visible light. In the case of the photocatalyst prepared in Example 3, in particular, The removal rate by the reaction was 80%, and the photodegradation rate was as high as 89.3%.

At this time, the removal rate by the photocatalytic reaction means the photocatalytic oxidation rate of toluene, and the photodegradation rate means the rate at which toluene decomposes toluene into CO ₂ and H ₂ O.

Claims (10)

Polymer matrix of porous structure;
A polymer matrix and an inorganic component doped with a metal,
Wherein the metal-doped inorganic component is 0.1 to 15 parts by weight based on 100 parts by weight of the polymer matrix.
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.
The method according to claim 1,
Wherein the photocatalyst has a BET specific surface area of 120 to 500 m ² / g.
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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