WO2007097220A1

WO2007097220A1 - Visible light-responsive photocatalyst

Info

Publication number: WO2007097220A1
Application number: PCT/JP2007/052457
Authority: WO
Inventors: Shinji Iwamoto; Hirotaka Ozaki; Masashi Inoue
Original assignee: Kyoto University
Priority date: 2006-02-21
Filing date: 2007-02-13
Publication date: 2007-08-30
Also published as: JPWO2007097220A1

Abstract

Disclosed is a visible light-responsive titania photocatalyst which is greatly improved in response to the visible light. Specifically disclosed is a visible light-responsive photocatalyst wherein a titania catalyst containing Ti, N and O as indispensable components is used as a carrier on which a transition metal is loaded.

Description

Specification

Visible light responsive photocatalyst

Technical field

[0001] The present invention relates to a visible light responsive photocatalyst. Specifically, the present invention relates to a titer photocatalyst having excellent visible light response. Specifically, a background art relating to a titania-based photocatalyst in which a transition metal is supported on a carrier based on a titanium-based catalyst containing a specific element as an essential component.

[0002] Photocatalysts have environmental purification functions such as air purification, water purification, deodorization, antibacterial, and antifouling! For this reason, as the need for environmental considerations increases, the photocatalyst market is expanding.

[0003] As a photocatalyst exhibiting a catalytic action for organic substance decomposition reaction, water decomposition reaction, and the like by light irradiation, titer (acid titanium) is known. The photocatalytic action of titaure is that when the titer absorbs light with energy larger than its band gap energy, electrons in the valence band are excited to the conduction band, and holes are generated in the valence band. Is exhibited by causing an oxidation / reduction reaction with an external substance on the catalyst surface (for example, see Patent Document 1)

) o

[0004] In addition, the titanium exhibits super hydrophilicity when irradiated with ultraviolet light. For this reason, for example, fogging of glass or mirrors can be prevented by irradiating glass or mirrors or the like whose surface is coated with titaure with ultraviolet light (see, for example, Patent Document 2).

[0005] Chitar exhibits photoresponsiveness (catalytic activity) only in the ultraviolet region, and does not exhibit photoresponsiveness in the visible light region that is abundant in sunlight. The ultraviolet light contained in sunlight is only about 3%. For this reason, the conventional titer cannot exhibit sufficient catalytic activity by solar energy. In addition, a conventional titer cannot be used as a photocatalyst in a place where light irradiation in the ultraviolet region cannot be sufficiently performed.

[0006] As a method for solving the above problem, a method of doping titanium with chromium or iron or a method of treating titanium with ammonia has been proposed. Such a treatment The titania thus produced becomes responsive not only to the ultraviolet light region but also to the visible light region (see, for example, Patent Documents 3 to 5). Therefore, for example, when a titer that has been subjected to the above treatment is used as a photocatalyst in a room (for example, a toilet or a bath), the organic matter is decomposed or the antifouling / deodorizing action is caused by irradiation with fluorescent light. Can be demonstrated.

[0007] In order to improve the response to the visible light region, a photocatalyst in which a silica-modified titer is treated with ammonia has been proposed (for example, see Patent Document 6). However, the response to the visible light region is still insufficient. Therefore, it is desired to provide a photocatalyst with greatly improved response to the visible light region.

Patent Document 1: JP-A-10-121266

Patent Document 2: Pamphlet of International Publication No. 96Z29375

Patent Document 3: Japanese Patent Laid-Open No. 9-192496

Patent Document 4: International Publication No. 01Z010552 Pamphlet

Patent Document 5: Japanese Unexamined Patent Publication No. 2003-200057

Patent Document 6: Japanese Unexamined Patent Publication No. 2006-21112

Disclosure of the invention

Problems to be solved by the invention

[0008] An object of the present invention is to provide a titania-based visible light responsive photocatalyst having greatly improved responsiveness to the visible light region.

Means for solving the problem

[0009] The visible light responsive photocatalyst of the present invention is a catalyst in which a titanium catalyst containing Ti, N, and O as essential components is used as a carrier, and a transition metal is supported on the carrier.

[0010] In a preferred embodiment, in the visible light responsive photocatalyst of the present invention, the carrier further contains Si. In a more preferred embodiment, the visible light responsive photocatalyst of the present invention is

The atomic ratio of SiZTi is 0.01 to 1.

[0011] In a preferred embodiment, the visible light responsive photocatalyst of the present invention is the transition metal.

Includes at least one selected from 1S W, Mo, V, and Fe.

[0012] In a preferred embodiment, the visible light responsive photocatalyst of the present invention is the above transition metal. Includes W. In a more preferred embodiment, the atomic ratio of WZTi is 0.03 to 0.15.

[0013] In a preferred embodiment, in the visible light responsive photocatalyst of the present invention, the transition metal contains Mo. In a more preferred embodiment, the atomic ratio of MoZTi is 0.01-0.05.

In a preferred embodiment, the visible light responsive photocatalyst of the present invention contains the above transition metal force. In a more preferred embodiment, the atomic ratio of VZTi is 0.0001-0.05.

[0015] In a preferred embodiment, the visible light responsive photocatalyst of the present invention contains the transition metal force SFe. In a more preferred embodiment, the atomic ratio of FeZTi is 0.0001-0.

The invention's effect

According to the present invention, a titanium-based visible light responsive photocatalyst exhibiting excellent responsiveness not only in the ultraviolet light region but also in the visible light region can be provided. In particular, the visible light responsive photocatalyst of the present invention has greatly improved responsiveness to the visible light region, and can exhibit excellent catalytic activity even in places with low light intensity, such as indoors.

Such an effect can be exhibited by a visible light responsive photocatalyst in which a transition metal is supported on a carrier based on a titanium catalyst containing specific elements such as Ti, N, and O as essential components. In addition, even if the amount of the transition metal to be supported is very small, the effects of the present invention can be sufficiently exerted. Brief Description of Drawings

FIG. 1 is a view showing an XRD pattern of a tungsten-supported titanium-based photocatalyst and XG (0.2).

FIG. 2 is a graph showing measurement results of photocatalytic activity with respect to visible light in Examples 1 to 1-10 and Comparative Examples 1 and 2.

FIG. 3 is a diagram showing an XRD pattern of molybdenum-supported titanium photocatalyst and XG (0.2). FIG. 4 is a graph showing measurement results of photocatalytic activity with respect to visible light in Examples 2-1 to 2-7 and Comparative Examples 1 and 2.

FIG. 5 is a diagram showing XRD patterns of vanadium-supported titanium photocatalyst and XG (0.2).

FIG. 6 is a graph showing the measurement results of photocatalytic activity with respect to visible light in Examples 3-1 to 3-8 and Comparative Examples 1 and 2.

FIG. 7 is a graph showing the measurement results of photocatalytic activity with respect to visible light in Examples 41 to 47 and Comparative Example 1.

FIG. 8 is a graph showing the results of Examples 1-6, 2-5, 3-6, 4-4, and Comparative Example 1, and the photocatalytic activity for visible light as a CO production rate. It is.

2

BEST MODE FOR CARRYING OUT THE INVENTION

[0018] The visible light responsive photocatalyst of the present invention uses a titanium catalyst (A) containing Ti, N, and O as essential components as a carrier. The titanium catalyst (A) is preferably a catalyst in which N is taken into the structure of titanium (acid titanium). The crystal structure of tita (acid titanium) can be either anatase or rutile. Anatase type is preferable.

[0019] The titanium catalyst (A) may further contain Si. Ti-containing catalyst containing Si (A

) Is the one in which Si is inserted or substituted at the site of tetrahedral hole Ti in the crystal lattice of titaure mainly having anatase type crystal structure.

[0020] The titanium catalyst (A) is preferably represented by the general formula (1).

TiSixNyOz (1)

Where 0≤x <l, 0 <y <0.3, 0 <z <2 + 2x.

[0021] When the titanium catalyst (A) does not contain Si as a component (that is, when x = 0 in the general formula (1)), the titanium catalyst (A) is It can be obtained by performing nitrogen introduction treatment on titaure. Any appropriate treatment method may be adopted as the nitrogen introduction treatment. Preferable is ammonia treatment, and examples thereof include methods described in JP-A-2003-200057 (Patent Document 5) and JP-A-2006-21112 (Patent Document 6).

[0022] When the titanium catalyst (A) contains Si as a component (that is, when 0 <x <1 in the general formula (1)), the titanium catalyst (A) is silica Nitrogen similar to the above in the modified titaure It can be obtained by performing an entry process. As a method for obtaining the silica-modified titer, any appropriate method can be adopted as long as Si can be inserted or substituted into the titania crystal structure. Preferably, JP-A-2000-254493 and JP-A-2006-21112 (Patent Document 6) can be used. When the titania-based catalyst (A) contains Si as a component, the atomic ratio of SiZTi is preferably from 0.01 to 1, more preferably from 0.03 to 0.7. The power is more preferably from 05 to 0.5, and particularly preferably from 0.07 to 0.4. When the atomic ratio of SiZTi is in such a range, the effects of the present invention are more easily exhibited.

[0023] The visible light responsive photocatalyst of the present invention is one in which the titania-based catalyst (A) is used as a carrier and a transition metal is supported on the carrier.

[0024] Any appropriate transition metal can be adopted as the transition metal. Preferably, V, Cr, Mn, Fe ゝ Co, Ni ゝ Cu ゝ Zn, Nb ゝ Mo, Tc ゝ Ru ゝ Rh, Pd ゝ Ag ゝ Ta ゝ W ゝ Re ゝ Os, Ir, Pt, Au, and more Preferred are V, Cr, Mn, Fe, Co, Ni ゝ Nb, Mo, Ta, and W, and more preferred are W, Mo, V, and Fe. These transition metals may be used alone or in combination of two or more.

[0025] The transition metal / Ti atom is preferably from 0.0001 to 0.50, more preferably from 0.0001 to 0.50, and even more preferably from 0.0001 to 0.20. When the atomic ratio of the transition metal ZTi is in such a range, the effect of the present invention is more easily exhibited.

[0026] For the loading of the transition metal, any suitable loading method can be adopted as long as it is a loading method of the transition metal on the solid catalyst. Preferably, it is supported by an impregnation method.

[0027] When W is used as the transition metal, for example, ammonium tungstate is dissolved in a small amount of water, and the above-mentioned titanium catalyst (A) is added and heated (for example, in a water bath at 80 ° C). The support can be carried out by impregnation by stirring in (above) and then firing at a high temperature (for example, 500 ° C.).

[0028] When W is used as the transition metal, the atomic ratio of WZTi is preferably 0.01 to 0.20, more preferably 0.03 to 0.15. When the atomic ratio of W / Ti is in such a range, the effect of the present invention is more easily exhibited. Further, the effect of the present invention can be sufficiently exerted even with such a small amount of W against Ti. [0029] When Mo is used as the transition metal, for example, ammonium molybdate is dissolved in a small amount of water, and the above-mentioned titanium catalyst (A) is added and heated (for example, on a water bath at 80 ° C). The impregnation can be carried out by stirring, followed by firing at a high temperature (for example, 500 ° C.) for supporting.

[0030] When Mo is used as the transition metal, the atomic ratio of MoZTi is preferably 0.001 to 0.10, more preferably 0.01 to 0.05. When the atomic ratio of Mo / Ti is in such a range, the effects of the present invention are more easily exhibited. Further, even if the amount of Mo with respect to Ti is such a small amount, the effect of the present invention can be sufficiently exerted.

[0031] When V is used as the transition metal, for example, ammonium vanadate is dissolved in a small amount of water, and the above-mentioned titanium catalyst (A) is added and heated (for example, on a water bath at 80 ° C). The impregnation can be performed by stirring, and then the support can be performed by firing at a high temperature (for example, 500 ° C.).

[0032] When V is used as the transition metal, the atomic ratio of VZTi is preferably 0.00005-0.10, more preferably 0.0001-0.05. When the V / Ti atomic ratio is in such a range, the effects of the present invention are more easily exhibited. Further, even if the amount of V with respect to Ti is very small, the effect of the present invention can be sufficiently exerted.

[0033] When Fe is used as the transition metal, for example, iron nitrate is dissolved in a small amount of water, and the above-mentioned titania-based catalyst (A) is added and stirred under heating (for example, on a water bath at 80 ° C). It is possible to carry out the support by impregnating the mixture and then baking at a high temperature (for example, 500 ° C.).

[0034] When Fe is used as the transition metal, the atomic ratio of FeZTi is preferably 0.0001-0.2, more preferably 0.0001-0.1, and even more preferably 0.005-0.07. . When the Fe / Ti atomic ratio is in such a range, the effects of the present invention are more easily exhibited. Further, the effect of the present invention can be sufficiently exerted even with such a small amount of Fe with respect to Ti.

[0035] In the present invention, any suitable transition metal can be used for a titanium-based catalyst containing Ti, N, and O as essential components, preferably a nitrogen-doped silica-modified titanium-based catalyst. Preferably, the addition of at least one transition metal selected from W, Mo, V, and Fe can significantly improve the photocatalytic activity under visible light irradiation. [0036] In general, the effects when a transition metal is added to a titanium catalyst are as follows: (1) Since the transition metal itself absorbs visible light, visible light responsiveness is expressed. (2) By acting as an electron acceptor and receiving electrons generated by light irradiation, one electron hole is separated, recombination occurs, and the efficiency of visible light response increases, and (3) the transition metal itself re- The three main reasons are that it works as a binding site and the efficiency of visible light response decreases. In (2) and (3), which force is likely to be given priority depends largely on the nature of the original titanium catalyst, and the amount of transition metal added is also present. It depends on the status. In the present invention, in the form of adding a transition metal to a titanium-based catalyst containing Ti, N, and O as essential components, it is considered that the increase in light absorption by the transition metal itself with a small amount of transition metal added is small. Therefore, the effect of (1) above is not so great. In the present invention, the effect of the above (2) is considered to be greater than the effect of the above (3) in the form in which the transition metal is added to the titania-based catalyst containing Ti, N, and O as essential components. The reason for this is thought to be that the titanium catalyst used in the present invention containing Ti, N, and O as essential components has excellent characteristics. In general, the effects of (3) are greater than the effects of (2) above in some cases where a significant improvement in activity is observed due to the addition of transition metals to the titanium catalyst. In many cases, responsiveness decreases.

[0037] In the present invention, at least one transition metal selected from W, Mo, V, and Fe is added as a transition metal to a titanium catalyst containing Ti, N, and O as essential components. The power when visible. Among these transition metals, which have higher photocatalytic activity for visible light, the addition of Fe as a transition metal has extremely high photocatalytic activity for visible light. Specifically, the nitrogen-doped silica modified titanium catalyst added with either W, Mo, or V has a photocatalytic activity for visible light as compared to a nitrogen-doped silica modified titanium catalyst with no transition metal added. Can be expressed about 3 times or more, and a nitrogen-doped silica modified titanium catalyst added with Fe can be expressed about 8 times or more. In addition, the nitrogen-doped silica modified titanium catalyst added with Fe can exhibit high activity even when a fluorescent lamp is used as a light source.

[0038] Recently, the recognition that high activity is difficult with a titer-based catalyst is partially spreading, and various composites based on niobium, tantalum, gallium, rare earth elements and the like are spreading. Studies on mixed oxides and compounds obtained by partially nitriding them have been widely conducted. However, elements such as niobium, tantalum, gallium, and rare earth elements are expensive, and safety and stability have not been sufficiently studied. Since the visible light responsive photocatalyst of the present invention is based on inexpensive, harmless and stable titanium oxide, it has a high possibility of practical use.

[0039] The visible light responsive photocatalyst of the present invention has a structure in which a transition metal is supported on a titania-based catalyst containing a specific element such as Ti, N, and O as an essential component. In addition, it exhibits excellent responsiveness not only in the visible light region, but particularly in the responsiveness in the visible light region. Specifically, in the UV-vis spectrum measurement result, when the absorbance at a wavelength of 300 nm (ultraviolet light region) is 1, the absorbance at a wavelength of 450 nm (visible light region) is preferably 0.2 or more, more preferably Is 0.25 or more, more preferably 0.3 or more, particularly preferably 0.35 or more, and most preferably 0.4 or more. The upper limit of the absorbance is practically preferably 1.0 or less. As described above, the visible light responsive photocatalyst of the present invention has greatly improved responsiveness to the visible light region, and the photocatalytic activity for visible light is much higher than that of a titania-based catalyst that does not carry a transition metal. Excellent!

[0040] The visible light responsive photocatalyst of the present invention is used on the wall surface, floor surface, ceiling surface, etc. of buildings and equipment; coating on furniture, glass, mirrors, lighting, tools, paper, cloth, plates, etc .; It can be used for various purposes such as application to photoelectric conversion materials; application to fields related to chemical 'electric reactions such as organic matter decomposition, radical generation, bleaching, etc.

Example

[0041] The present invention will be further described using examples and comparative examples. In addition, this invention is not limited only to these Examples. The analysis methods used in the examples are as follows.

[0042] [Catalyst composition]

The catalyst composition was measured by an X-ray photoelectron spectrometer (XPS) (manufactured by ULVAC—PHI, model number: Model 5500).

[XRD measurement] XRD measurement was performed with an XRD measurement apparatus (manufactured by Shimadzu Corporation, model number: XD—D1). [Measurement of photocatalytic activity to visible light]

0.2 g of the photocatalyst to be measured was uniformly dispersed on a 90 mm Φ glass filter paper and placed in a 1 L glass container to be sealed. In this state, 0.2 mmol of acetoaldehyde was added to the container and left in the dark for 1 hour. After that, light irradiation was performed using a 300W xenon lamp equipped with a cut-off filter capable of cutting ultraviolet light as a light source, and the amount of CO produced after a predetermined time was measured by gas chromatography.

2

[Measurement of UV-vis spectrum]

The UV-vis spectrum was measured with a UV-vis spectrum measuring apparatus (manufactured by Shimadzu Corporation, model number: MPS-2000).

[Production Example 1]: Production of nitrogen-introduced silica-modified titanium photocatalyst XG (0.2)

12.573 g of titanium tetraisopropoxide, 1.848 g of tetraethyl orthokeate, and lOOmL of 1,4-butanediol were mixed (SiZTi charge ratio (molar ratio) = 0.2) and then placed on an autoclave. After substituting the system with nitrogen, the temperature was raised from room temperature to 300 ° C in 2.3 ° CZ minutes and kept at 300 ° C for 2 hours. The autoclave nozzle was opened with the temperature kept at around 300 ° C, and the solvent was distilled off to obtain a xerogel product. This was calcined in air at 500 ° C. for 30 minutes to obtain a silica modified titer.

[0044] After 0.3 g of the obtained silica modified titer was filled into the tube, ammonia gas was poured into the tube at lOOmLZmin, and heat treatment was performed at 600 ° C for 1 hour, and then in the air. Annealing was performed at 500 ° C. Thereby, ammonia treatment was performed uniformly and efficiently, and a nitrogen-introduced silica-modified titania photocatalyst in which nitrogen was introduced into the crystal structure was obtained. The nitrogen-introduced silica modified titer photocatalyst obtained by this method is represented as XG (0.2).

[Production Example 2]: Production of nitrogen-introduced titania photocatalyst XG (0)

The silica was modified, and the titanium was treated with ammonia in the same manner as in Production Example 1 to obtain a nitrogen-introduced titania photocatalyst. The nitrogen-introduced titania photocatalyst obtained by this method is represented as X G (O).

[Example 1 1]: Titania photocatalyst (1 1) (TiZSiZW (atomic ratio) = 100Z20Z20) Add 0.3 g of XG (0.2) obtained in Production Example 1 to 0.1 g of ammonium tungstate dissolved in 5 ml of water, stir on an 80 ° C water bath, and then 500 ° By firing with C, a titanium-based photocatalyst (1-1) carrying tungsten was obtained. The resulting titania photocatalyst (1-1) was TiZSiZW (atomic ratio) = 100Z20Z20. Figure 1 shows the XRD pattern of the titanium photocatalyst (11).

[0047] With respect to the obtained titanium photocatalyst (11) (TiZSiZW (atomic ratio) = 100 to 20 to 20), the photocatalytic activity for visible light was measured by the method described above. The result is shown in figure 2.

[0048] As a result of measuring the UV-vis spectrum of the obtained titanium photocatalyst (11) (TiZSiZW (atomic ratio) = 100-2020), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.327.

[Example 1 2]: Titania-based photocatalyst (1 2) (TiZSiZW (atomic ratio) = 100Z20Z15) obtained in Preparation Example 1 in which 0.1 g of ammonium tungstate was dissolved in 5 ml of water A titanium photocatalyst (1-2) with TiZSiZW (atomic ratio) = 100Z20Z15 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added. Fig. 1 shows the XRD pattern of the titanium photocatalyst (1-2).

[0050] The obtained photocatalyst activity (12) (TiZSiZW (atomic ratio) = 100Z20Z15) was measured for photocatalytic activity with respect to visible light by the method described above. The result is shown in figure 2.

[0051] As a result of measuring the UV-vis spectrum of the obtained titanium photocatalyst (12) (TiZSiZW (atomic ratio) = 100 to 20-15), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.314.

[0052] [Example 1 3]: Titania-based photocatalyst (1 3) (TiZSiZW (atomic ratio) = 100Z20Z10)

Ammonium tungstate 0.0852 g dissolved in 3 ml of water was prepared in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) obtained in Production Example 1 was added. TiZSiZW A titanium photocatalyst (13) having an atomic ratio of 100Z20Z10 was obtained. Figure 1 shows the XRD pattern of the titanium photocatalyst (13).

[0053] The obtained titanium photocatalyst (1 3) (TiZSiZW (atomic ratio) = 100Z20Z10) Then, the photocatalytic activity for visible light was measured by the method described above. Figure the result

Shown in 2.

[0054] As a result of measuring the UV-vis spectrum of the obtained titanium photocatalyst (13) (TiZSiZW (atomic ratio) = 100Z20Z10), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.446.

[Example 14]: Titania-based photocatalyst (14) (TiZSiZW (atomic ratio) = 100Z20Z8) Obtained in Preparation Example 1 by dissolving 0.0682 g of ammonium tungstate in 3 ml of water A titanium photocatalyst (1-4) with TiZSiZW (atomic ratio) = 100Z20Z8 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added. Fig. 1 shows the XRD pattern of the titanium photocatalyst (1-4).

With respect to the obtained titer photocatalyst (14) (TiZSiZW (atomic ratio) = 100Z20Z8), the photocatalytic activity for visible light was measured by the method described above. The result is shown in figure 2.

[0057] The obtained titer photocatalyst (14) (TiZSiZW (atomic ratio) = 100 ~ 20 ~ 8) was measured for UV-vis spectrum. As a result, the absorbance at wavelength 300nm (ultraviolet light region) was 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.348.

[Example 15]: Titania-based photocatalyst (15) (TiZSiZW (atomic ratio) = 100Z20Z7) Obtained in Preparation Example 1 by dissolving 0.0060 g of ammonium tungstate in 3 ml of water A titania photocatalyst (1-5) having TiZSiZW (atomic ratio) = 100Z20Z7 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added.

[0059] The obtained photocatalyst activity (15) (TiZSiZW (atomic ratio) = 100Z20Z7) was measured for photocatalytic activity with respect to visible light by the method described above. The result is shown in figure 2.

[0060] As a result of measuring the UV-vis spectrum of the obtained tita-based photocatalyst (15) (TiZSiZW (atomic ratio) = 100 to 20-7), the absorbance at a wavelength of 300 nm (ultraviolet light region) is 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.398.

[0061] [Example 16]: Titania-based photocatalyst (16) (TiZSiZW (atomic ratio) = 100Z20Z6) Obtained in Preparation Example 1 by dissolving ammonium tungstate 0.05 llg in 3 ml of water The titania photocatalyst (1-6) with TiZSiZW (atomic ratio) = 100Z20Z6 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added.

[0062] With respect to the obtained titer photocatalyst (16) (TiZSiZW (atomic ratio) = 100Z20Z6), the photocatalytic activity for visible light was measured by the method described above. The result is shown in figure 2. In addition, a graph showing photocatalytic activity for visible light in terms of CO production rate is shown.

It is shown in 2-8.

[0063] As a result of measuring the UV-vis spectrum of the obtained titer photocatalyst (16) (TiZSiZW (atomic ratio) = 100Z20Z6), the absorbance at a wavelength of 300 nm (ultraviolet light region) is 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.385.

[Example 17]: Titania-based photocatalyst (17) (TiZSiZW (atomic ratio) = 100Z20Z5) Obtained in Preparation Example 1 by dissolving 0.0425 g of ammonium tungstate in 3 ml of water A titanium photocatalyst (1-7) with TiZSiZW (atomic ratio) = 100Z20Z5 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added. Fig. 1 shows the XRD pattern of the titanium photocatalyst (1-7).

The obtained photocatalytic catalyst (17) (TiZSiZW (atomic ratio) = 100Z20Z5) was measured for photocatalytic activity with respect to visible light by the method described above. The result is shown in figure 2.

[0066] The obtained titer photocatalyst (17) (TiZSiZW (atomic ratio) = 100 to 20 to 5) was measured for UV-vis spectrum. As a result, the absorbance at wavelength 300nm (ultraviolet light region) was 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.409.

[Example 8]: Titania-based photocatalyst (18) (TiZSiZW (atomic ratio) = 100Z20Z4) obtained in Production Example 1 in which 0.0341 g of ammonium tungstate was dissolved in 3 ml of water A titania photocatalyst (1-8) with TiZSiZW (atomic ratio) = 100Z20Z4 was obtained in the same manner as in Example 1-1 except that 0.3 g of XG (0.2) was added.

[0068] The obtained photocatalyst activity (18) (TiZSiZW (atomic ratio) = 100Z20Z4) was measured for photocatalytic activity with respect to visible light by the method described above. The result is shown in figure 2.

[0069] About the resulting titanium photocatalyst (18) (TiZSiZW (atomic ratio) = 100 = 20Ζ4) As a result of measuring the UV-vis spectrum, when the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1, the absorbance at a wavelength of 450 nm (visible light region) was 0.384.

[Example 1 9]: Titania-based photocatalyst (19) (TiZSiZW (atomic ratio) = 100Z20Z3) Obtained in Production Example 1 by dissolving 0.0255 g of ammonium tungstate in 3 ml of water Except that 0.3g of XG (0.2) was added, the same procedure as in Example 1-1 was performed, and TiZSiZW (atomic ratio)

A titer photocatalyst (1-9) of 100Z20Z3 was obtained. X-ray photocatalyst (1-9)

Figure 1 shows the RD pattern.

[0071] The obtained photocatalyst activity (19) (TiZSiZW (atomic ratio) = 100Z20Z3) was measured for photocatalytic activity with respect to visible light by the method described above. The result is shown in figure 2.

[0072] The obtained titer photocatalyst (19) (TiZSiZW (atomic ratio) = 100 to 20 3) was measured for UV-vis spectrum. As a result, the absorbance at wavelength 300nm (ultraviolet region) was 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.495.

[Example 10]: Titer-based photocatalyst (1-10) (TiZSiZW (atomic ratio) = 100Z20Z 1)

Except that 0.3 g of XG (0.2) obtained in Production Example 1 was added to a solution obtained by dissolving 0.00085 g of ammonium tungstate in 3 ml of water, the same procedure as in Example 1-1 was performed, and TiZSiZW A titanium photocatalyst (1-10) having an atomic ratio of 100Z20Z1 was obtained. Fig. 1 shows the XRD pattern of the titanium photocatalyst (1-10).

[0074] The photocatalytic activity for visible light was measured for the obtained titer photocatalyst (110) (TiZSiZW (atomic ratio) = 100Z20Zl) by the method described above. Figure the result

Shown in 2.

[0075] As a result of measuring the UV-vis spectrum of the obtained titer photocatalyst (110) (TiZSiZW (atomic ratio) = 100Z20Zl), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.468.

[Example 2-1]: Titania photocatalyst (2-1) (TiZSiZMo (atomic ratio) = 100Z20Z10)

Ammonium molybdate obtained in Preparation Example 1 in 0.0576 g dissolved in 3 ml of water Add 0.3g of XG (0.2), stir on a water bath at 80 ° C, and then calcinate at 500 ° C, so that the titanium-based photocatalyst (2-1) supporting molybdenum was gotten. The obtained titanium photocatalyst (2-1) was TiZSiZMo (atomic ratio) = 100Z20Z10. Figure 3 shows the XRD pattern of the titanium photocatalyst (2-1).

[0077] With respect to the obtained titania-based photocatalyst (2-1) (TiZSiZMo (atomic ratio) = 100 to 20 to 10), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 4.

[0078] The obtained titania photocatalyst (2-1) (TiZSiZMo (atomic ratio) = 100 to 20 to 10) was measured for UV-vis spectrum. As a result, the absorbance at wavelength 300nm (ultraviolet region) was 1. The absorbance at a wavelength of 450 nm (visible light region) was 0.433.

[Example 2-2]: Titania-based photocatalyst (2-2) (TiZSiZMo (atomic ratio) = 100Z20Z7) Ammonium molybdate 0.0403 g obtained in Preparation Example 1 dissolved in 3 ml of water Was

Except that 0.3 g of XG (0.2) was added, the same procedure as in Example 2-1 was performed. TiZSiZMo (atomic ratio)

A titanium-based photocatalyst (2-2) of 100Z20Z7 was obtained. X-rays of titanium photocatalyst (2-2)

Figure 3 shows the RD pattern.

With respect to the obtained titania-based photocatalyst (2-2) (TiZSiZMo (atomic ratio) = 100Z20Z7), the photocatalytic activity with respect to visible light was measured by the method described above. Figure the result

Shown in 4.

[0081] As a result of measuring the UV-vis spectrum of the obtained titania-based photocatalyst (2-2) (TiZSiZMo (atomic ratio) = 100 to 20-7), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.380.

[Example 2-3]: Titania photocatalyst (2-3) (TiZSiZMo (atomic ratio) = 100Z20Z5) Ammonium molybdate 0.0288 g obtained in Preparation Example 1 in 3 ml of water A titanium photocatalyst (2-3) with TiZSiZMo (atomic ratio) = 100Z20Z5 was obtained except that 0.3 g of the obtained XG (0.2) was added. Fig. 3 shows the XRD pattern of the titanium photocatalyst (2-3).

[0083] The obtained titania photocatalyst (2-3) (TiZSiZMo (atomic ratio) = 100Z20Z5) Then, the photocatalytic activity for visible light was measured by the method described above. Figure the result

Shown in 4.

[0084] UV-vis spectrum of the obtained titania photocatalyst (2-3) (TiZSiZMo (atomic ratio) = 100Z20Z5) was measured, and the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.378.

[Example 2-4]: Titania-based photocatalyst (2-4) (TiZSiZMo (atomic ratio) = 100Z20Z4)

Except that 0.3 g of XG (0.2) obtained in Production Example 1 was added to 0.0230 g of molybdenum molybdate dissolved in 3 ml of water, the same procedure as in Example 2-1 was performed, and TiZSiZMo A titania photocatalyst (2-4) having an atomic ratio of 100Z20Z4 was obtained.

With respect to the obtained titania photocatalyst (2-4) (TiZSiZMo (atomic ratio) = 100Z20Z4), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 4.

[0087] As a result of measuring the UV-vis spectrum of the obtained titania-based photocatalyst (2-4) (TiZSiZMo (atomic ratio) = 100 to 20-4), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.386.

[0088] [Example 2-5]: Titania-based photocatalyst (2-5) (TiZSiZMo (atomic ratio) = 100Z20Z3) Obtained in Production Example 1 by dissolving 0.0173 g of ammonium molybdate in 3 ml of water A titanium photocatalyst (2-5) with TiZSiZMo (atomic ratio) = 100Z20Z3 was obtained except that 0.3 g of the obtained XG (0.2) was added. Fig. 3 shows the XRD pattern of the titanium photocatalyst (2-5).

For the obtained titania-based photocatalyst (2-5) (TiZSiZMo (atomic ratio) = 100Z20Z3), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 4. In addition, a graph showing photocatalytic activity for visible light in terms of CO production rate is shown in Fig. 8.

2

Shown in

[0090] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (2-5) (TiZSiZMo (atomic ratio) = 100Z20Z3), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.390.

[Example 2-6]: Titania photocatalyst (2-6) (TiZSiZMo (atomic ratio) = 100Z20Z2) Ammonium molybdate was prepared in the same manner as in Example 2-1 except that 0.315 g of XG (0.2) obtained in Production Example 1 was added to 3 ml of water dissolved in 0.115 g of water, and TiZSiZMo A titania photocatalyst (2-6) of (atomic ratio) = 100Z20Z2 was obtained.

With respect to the obtained titania-based photocatalyst (2-6) (TiZSiZMo (atomic ratio) = 100Z20Z2), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 4.

[0093] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (2-6) (TiZSiZMo (atomic ratio) = 100 to 20 2), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.384.

[Example 2-7]: Titania-based photocatalyst (2-7) (TiZSiZMo (atomic ratio) = 100Z20ZD Ammonium molybdate 0.005 g obtained in Preparation Example 1 was dissolved in 3 ml of water. Except that 0.3 g of XG (0.2) was added, the same procedure as in Example 2-1 was performed to obtain a titanium photocatalyst (2-7) with TiZSiZMo (atomic ratio) = 100Z20Z1. Figure 3 shows the XRD pattern of the photocatalyst (2-7).

With respect to the obtained titania-based photocatalyst (2-7) (TiZSiZMo (atomic ratio) = 100Z20Zl), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 4.

[0096] The obtained titania photocatalyst (2-7) (TiZSiZMo (atomic ratio) = 100Z20Zl) was measured for UV-vis spectrum. As a result, the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.393.

[0097] [Example 3-1]: Titania photocatalyst (3-1) (TiZSiZV (atomic ratio) = 100Z20Z10) Obtained in Production Example 1 by dissolving 0.0382 g of ammonium vanadate in 3 ml of water 0.3 g of the obtained XG (0.2) was added, stirred on a water bath at 80 ° C, and then calcined at 500 ° C, so that a photocatalyst supported on vanadium (3- 1) was obtained. The obtained titanium photocatalyst (3-1) was TiZSiZV (atomic ratio) = 100Z20Z10. Figure 5 shows the XRD pattern of the titanium photocatalyst (3-1).

With respect to the obtained titania-based photocatalyst (3-1) (TiZSiZV (atomic ratio) = 100 to 20 to 10), the photocatalytic activity with respect to visible light was measured by the method described above. Figure the result Shown in 6.

[0099] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (3-1) (TiZSiZV (atomic ratio) = 100Z20Z10), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1. In some cases, the absorbance at a wavelength of 450 nm (visible light region) was 0.690.

[0100] [Example 3-2]: Titania photocatalyst (3-2) (TiZSiZV (atomic ratio) = 100Z20Z7) Ammonium vanadate 0.0267 g obtained in Preparation Example 1 in 3 ml of water Except that 0.3 g of the obtained XG (0.2) was added, the same procedure as in Example 3-1 was performed to obtain a titanium-based photocatalyst (3-2) with Ti / SiZV (atomic ratio) = 100Z20Z7. It was. Fig. 5 shows the XRD pattern of the titanium photocatalyst (3-2).

[0101] For the resulting titanium photocatalyst (3-2) (Ti / Si / V (atomic ratio) = 100/20/7)! Was measured. The results are shown in Fig. 6.

[0102] As a result of measuring the UV-vis spectrum of the obtained titanium photocatalyst (3-2) (Ti / Si / V (atomic ratio) = 100/20/7)! When the absorbance at 300 nm (ultraviolet light region) was 1, the absorbance at a wavelength of 450 nm (visible light region) was 0.631.

[Example 3-3]: Titania-based photocatalyst (3-3) (TiZSiZV (atomic ratio) = 100Z20Z5) Obtained in Production Example 1 by dissolving 0.0191 g of ammonium vanadate in 3 ml of water Except that 0.3 g of the obtained XG (0.2) was added, the same procedure as in Example 3-1 was performed to obtain a titanium-based photocatalyst (3-3) with Ti / SiZV (atomic ratio) = 1 OOZ20Z5. It was. Fig. 5 shows the XRD pattern of the titanium photocatalyst (3-3).

[0104] The obtained photocatalytic activity (3-3) (Ti / Si / V (atomic ratio) = 100/20/5) was obtained! Was measured. The results are shown in Fig. 6.

[0105] As a result of measuring the UV-vis spectrum for the obtained titanium photocatalyst (3-3) (Ti / Si / V (atomic ratio) = 100/20/5)! When the absorbance at 300 nm (ultraviolet light region) was 1, the absorbance at a wavelength of 450 nm (visible light region) was 0.493.

[Example 3-4]: Titania-based photocatalyst (3-4) (TiZSiZV (atomic ratio) = 100Z20Z3) Obtained in Production Example 1 by dissolving 0.0115 g of ammonium vanadate in 3 ml of water X A titanium photocatalyst (3-4) with Ti / SiZV (atomic ratio) = 1 OOZ20Z3 was obtained except that 0.3 g of G (0.2) was added. Fig. 5 shows the XRD pattern of the titanium photocatalyst (3-4).

[0107] With respect to the obtained titania-based photocatalyst (3-4) (TiZSiZV (atomic ratio) = 100Z20Z3), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 6.

[0108] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (3-4) (TiZSiZV (atomic ratio) = 100 ~ 20 ~ 3), the absorbance at wavelength 300nm (ultraviolet light region) is 1. The absorbance at a wavelength of 450 nm (visible light region) was 0.394.

[Example 3-5]: Titania-based photocatalyst (3-5) (TiZSiZV (atomic ratio) = 100Z20Zl) Ammonium vanadate 0.003 g obtained in Preparation Example 1 was dissolved in 3 ml of water. Except that 0.3 g of the obtained XG (0.2) was added, the same procedure as in Example 3-1 was performed to obtain a titanium photocatalyst (3-5) with Ti / SiZV (atomic ratio) = 100Z20Z1. It was. Fig. 5 shows the XRD pattern of the titanium photocatalyst (3-5).

[0110] The obtained titania photocatalyst (3-5) (TiZSiZV (atomic ratio) = 100Z20Zl) was measured for photocatalytic activity with respect to visible light by the method described above. The results are shown in Fig. 6.

[0111] The obtained titania photocatalyst (3-5) (TiZSiZV (atomic ratio) = 100Z20Zl) was measured for UV-vis spectrum. As a result, the absorbance at wavelength 300nm (ultraviolet region) was 1. The absorbance at a wavelength of 450 nm (visible light region) was 0.427.

[Example 3-6]: Titania photocatalyst (3-6) (TiZSiZV (atomic ratio) = 100Z20Z0.5)

1. 0 X 10 ^_2 molZL of ammonium vanadate aqueous solution 1. Executed except that 470 ml of water 1.470 ml was added and 0.3 g of XG (0.2) obtained in Production Example 1 was added. The same procedure as in Example 3-1 was performed to obtain a titanium photocatalyst (3-6) with TiZSiZV (atomic ratio) = 100Z20Z0.5.

[0113] With respect to the obtained titania-based photocatalyst (3-6) (TiZSiZV (atomic ratio) = 100 to 20 to 0.5), the photocatalytic activity with respect to visible light was measured by the method described above. Figure the result Shown in 6. In addition, a graph showing photocatalytic activity for visible light in terms of CO production rate is shown in Fig. 8.

2

Shown in

[0114] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (3-6) (TiZSiZV (atomic ratio) = 100Z20Z0.5), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1 The absorbance at a wavelength of 450 nm (visible light region) was 0.427.

[Example 3-7]: Titer-based photocatalyst (3-7) (TiZSiZV (atomic ratio) = 100Z20Z0.1)

1. 0 X 10 ^_2 molZL aqueous solution of ammonium vanadate 0. Except for adding 326 ml to water 2.674 ml, adding 0.3 g of XG (0.2) obtained in Production Example 1 The same procedure as in Example 3-1 was performed to obtain a titanium photocatalyst (3-7) with TiZSiZV (atomic ratio) = 100Z20Z0.1.

[0116] With respect to the obtained titania-based photocatalyst (3-7) (TiZSiZV (atomic ratio) = 100 to 20 to 0.1), the photocatalytic activity with respect to visible light was measured by the method described above. The result is shown in FIG.

[0117] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (3-7) (TiZSiZV (atomic ratio) = 100 to 20 to 0.1), the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1 The absorbance at a wavelength of 450 nm (visible light region) was 0.410.

[Example 3-8]: Titania photocatalyst (3-8) (TiZSiZV (atomic ratio) = 100Z20Z0. 0 1)

1. 0 X 10 ^_3 molZL aqueous solution of ammonium vanadate 0. Except for adding 326 ml to water 2.674 ml, adding 0.3 g of XG (0.2) obtained in Production Example 1 A titanium photocatalyst (3-8) with TiZSiZV (atomic ratio) = 100Z20Z0.01 was obtained in the same manner as Example 3-1.

[0119] With respect to the obtained titania-based photocatalyst (3-8) (TiZSiZV (atomic ratio) = 100 to 20 to 0.01), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 6.

[0120] As a result of measuring the UV-vis spectrum of the obtained titania-based photocatalyst (3-8) (TiZSiZV (atomic ratio) = 100 to 20 to 0.01), absorption at a wavelength of 300 nm (ultraviolet light region) was observed. When the luminous intensity was 1, the absorbance at a wavelength of 450 nm (visible light region) was 0.401.

[Example 4 1]: Titania-based photocatalyst (4 1) (TiZSiZFe (atomic ratio) = 100Z20Z10)

Add 0.3 g of XG (0.2) obtained in Production Example 1 to 0.11319 g of iron nitrate dissolved in 3 ml of water, stir on an 80 ° C water bath, and then calcinate at 500 ° C. As a result, a titania photocatalyst (41) carrying iron was obtained. The obtained titania-based photocatalyst (41) had TiZSiZFe (atomic ratio) = 100Z20Z10.

[0122] About the obtained titania-based photocatalyst (41) (TiZSiZFe (atomic ratio) = 100 to 20 to 10), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in FIG.

[0123] UV-vis spectrum of the titania-based photocatalyst (4 1) (TiZSiZFe (atomic ratio) = 100 ~ 20 ~ 10) was measured. As a result, the absorbance at wavelength 300nm (ultraviolet light region) was 1. Further, the absorbance at a wavelength of 450 nm (visible light region) was 0.597.

[Example 4 2]: Titania-based photocatalyst (4 2) (TiZSiZFe (atomic ratio) = 10θΖ2θΖ7) Iron nitrate 0.03 g was dissolved in 3 ml of water, and XG (0 (2) was carried out in the same manner as in Example 4-1, except that 0.3 g was obtained, to obtain a titanium photocatalyst (42) with TiZSiZFe (atomic ratio) = 100/20/7.

[0125] The obtained titania photocatalyst (4 2) (TiZSiZFe (atomic ratio) = 100Z20Z7) was measured for photocatalytic activity with respect to visible light by the method described above. Figure 7 shows the results.

[0126] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (4 2) (TiZSiZFe (atomic ratio) = 100 to 20-7), when the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1, Absorbance at a wavelength of 450 nm (visible light region) was 0.572.

[Example 4 3]: Titania-based photocatalyst (4 3) (TiZSiZFe (atomic ratio) = 10θΖ2θΖ5) 0.0G of iron nitrate dissolved in 3 ml of water was dissolved in XG (0 (2) was carried out in the same manner as in Example 4-1, except that 0.3 g was obtained, to obtain a titanium photocatalyst (43) with TiZSiZFe (atomic ratio) = 100/20/5. The obtained titania photocatalyst (4 3) (TiZSiZFe (atomic ratio) = 100Z20Z5) was measured for photocatalytic activity with respect to visible light by the method described above. Figure 7 shows the results.

[0129] As a result of measuring the UV-vis spectrum of the obtained titania-based photocatalyst (4 3) (TiZSiZFe (atomic ratio) = 100 to 20-5), when the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1, Absorbance at a wavelength of 450 nm (visible light region) was 0.455.

[Example 4 4]: Titania-based photocatalyst (4 4) (TiZSiZFe (atomic ratio) = 100Z20Z3) 0.0G of iron nitrate was dissolved in 3 ml of water, and XG (0 .2) was carried out in the same manner as in Example 4-1, except that 0.3 g was added, to obtain a titania photocatalyst (44) with TiZSiZFe (atomic ratio) = 100/20/3.

The obtained titania photocatalyst (4 4) (TiZSiZFe (atomic ratio) = 100Z20Z3) was measured for photocatalytic activity with respect to visible light by the method described above. Figure 7 shows the results. In addition, a graph showing photocatalytic activity for visible light in terms of CO production rate is shown in Fig. 8.

2

Shown in

[0132] As a result of measuring the UV-vis spectrum of the obtained titania photocatalyst (4 4) (TiZSiZFe (atomic ratio) = 100Z20Z3), when the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1, Absorbance at a wavelength of 450 nm (visible light region) was 0.444.

[Example 4 5]: Titania-based photocatalyst (4 5) (TiZSiZFe (atomic ratio) = 100Z20ZD 0.0G of iron nitrate was dissolved in 3 ml of water, and XG (0. A titanium photocatalyst (45) with TiZSiZFe (atomic ratio) = 100/20/1 was obtained in the same manner as in Example 4-1, except that 0.3 g of 2) was added.

[0134] With respect to the obtained titania photocatalyst (45) (TiZSiZFe (atomic ratio) = 100Z20Zl), the photocatalytic activity with respect to visible light was measured by the method described above. Figure 7 shows the results.

[0135] The obtained titania photocatalyst (4 5) (TiZSiZFe (atomic ratio) = 100Z20Zl) was measured for UV-vis spectrum. As a result, when the absorbance at a wavelength of 300 nm (ultraviolet light region) was 1, Absorbance at a wavelength of 450 nm (visible light region) was 0.397.

[Example 4 6]: Titania-based photocatalyst (4 6) (TiZSiZFe (atomic ratio) = 10θΖ2θΖ〇. Five)

1. 0 X 10 ^_2 molZL of iron nitrate solution 1. Example with the exception of adding 0.3 g of XG (0.2) obtained in Production Example 1 to 630 ml with 1.370 ml of water. In the same manner as in 4-1, a titania photocatalyst (4 6) with TiZS iZFe (atomic ratio) = 100Z20Z0.5 was obtained.

[0137] With respect to the obtained titania-based photocatalyst (4 6) (TiZSiZFe (atomic ratio) = 100 to 20 to 0.5), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 7.

[0138] As a result of measuring the UV-vis spectrum for the obtained titania-based photocatalyst (4 6) (TiZSiZFe (atomic ratio) = 100 to 20 to 0.5), the absorbance at a wavelength of 300 nm (ultraviolet region) was set to 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.392.

[Example 4 7]: Titania-based photocatalyst (4 7) (TiZSiZFe (atomic ratio) = 10θΖ2θΖ〇.

1)

1. 0 X 10 ^_2 molZL of iron nitrate aqueous solution 0.3 Example with the exception of adding 0.3 g of XG (0.2) obtained in Production Example 1 to 2.326 ml with water 2.674 ml This was carried out in the same manner as in 4-1, and a titanium photocatalyst (47) with TiZS iZFe (atomic ratio) = 100Z20Z0.1 was obtained.

[0140] With respect to the obtained titania-based photocatalyst (47) (TiZSiZFe (atomic ratio) = 100 to 20 to 0.1), the photocatalytic activity with respect to visible light was measured by the method described above. The results are shown in Fig. 7.

[0141] As a result of measuring the UV-vis spectrum of the titania photocatalyst (4 7) (TiZSiZFe (atomic ratio) = 100 to 20 to 0.1), the absorbance at a wavelength of 300 nm (ultraviolet region) was set to 1. In this case, the absorbance at a wavelength of 450 nm (visible light region) was 0.382.

[0142] [Comparative Example 1]: Titania photocatalyst (C1)

By adding 0.3 g of XG (0.2) obtained in Production Example 1 to 3 ml of water and drying at 80 ° C., a titer photocatalyst (C1) was obtained. Figures 1, 3 and 5 show the XRD patterns of the tita-based photocatalyst (C1).

[0143] About the obtained titania-based photocatalyst (C1), the above-mentioned method was applied to visible light. The photocatalytic activity was measured. The results are shown in Figs. Figure 8 shows a graph showing the photocatalytic activity for visible light in terms of CO production rate.

2

[Comparative Example 2]: Titania photocatalyst (C2)

A titer photocatalyst (C2) was obtained by adding 0.3 g of XG (0) obtained in Production Example 2 to 3 ml of water and drying at 80 ° C.

[0145] The titania photocatalyst (C2) obtained was measured for photocatalytic activity with respect to visible light by the method described above. The results are shown in Figs.

[0146] [Evaluation]

According to FIGS. 2, 4, 6 and 7, the transition metal-supported titanium photocatalysts (1 1) to (1 1 0) (in particular, (1 3) to (1 8)), (2 — 1) to (2-7), (3-1) to (3-8) (especially (3-3) to (3-8)), (4 1) to (4 7) (especially , (4 2) to (4 6)) show that the photocatalytic activity for visible light is very high compared to titania-based photocatalysts (C1) and (C2) that do not carry transition metals. . Further, it can be seen that the effect of the present invention is sufficiently exhibited even when the amount of the transition metal to be supported is extremely small.

According to FIG. 8, when a titanium catalyst containing Ti, N, and O as an essential component is added with at least one transition metal selected from W, Mo, V, and Fe as a transition metal, the force Among these transition metals, which have higher photocatalytic activity for visible light, it can be seen that when Fe is added as a transition metal, the photocatalytic activity for visible light is extremely high.

Titania-based photocatalysts supported by transition metals (11) to (110), (2-1) to (2-7), (3-1) to (3-8), (4 1) to (4 7), when the absorbance at a wavelength of 300 nm (ultraviolet light region) is 1, the absorbance at a wavelength of 450 nm (visible light region) is about 0.3 to 0.7, and the response to the visible light region is very high. It turns out to be expensive.

Industrial applicability

[0147] The titanium-based photocatalyst of the present invention has a very high photocatalytic activity for visible light. Therefore, it can be used not only in places where sunlight can be irradiated, but also in places where sufficient UV intensity cannot be obtained, such as indoors.

Claims

The scope of the claims

[I] A visible light responsive photocatalyst using a titanium-based catalyst containing Ti, N, and O as essential components as a carrier and a transition metal supported on the carrier.

[2] The visible light responsive photocatalyst according to claim 1, wherein the carrier further contains Si.

[3] The visible light responsive photocatalyst according to claim 2, wherein the atomic ratio of SiZTi is 0.01 to 1.

[4] The transition metal according to claim 1, wherein the transition metal includes at least one selected from W, Mo, V, and Fe.

The visible light responsive photocatalyst described in any of up to 3.

5. The visible light responsive photocatalyst according to claim 4, wherein the transition metal contains W.

6. The visible light responsive photocatalyst according to claim 5, wherein the atomic ratio of WZTi is 0.03 to 0.15.

7. The visible light responsive photocatalyst according to claim 4, wherein the transition metal contains Mo.

[8] The visible light responsive photocatalyst according to claim 7, wherein the atomic ratio of MoZTi is 0.01 to 0.05.

[9] The visible light responsive photocatalyst according to claim 4, wherein the transition metal contains V.

[10] The visible light responsive photocatalyst according to claim 9, wherein the atomic ratio of VZTi is 0.0001-0.05.

[II] The visible light responsive photocatalyst according to claim 4, wherein the transition metal contains Fe.

[12] The visible light responsive photocatalyst according to claim 11, wherein the atomic ratio of FeZTi is 0.0001-0.