KR20100025258A - Photocatalyst sol and manufacturing method thereof - Google Patents

Abstract

PURPOSE: A composite material photocatalyst sol and a method for manufacturing the photocatalyst sol are provided to obtain excellent antibacterial and anti-fungi performance and to have an air cleaning function according to a discharge of far-infrared radiation and an anion. CONSTITUTION: A method for manufacturing a composite material photocatalyst sol comrpsies: a step of manufacturing titanium dioxide(TiO2) sol by mixing a titanium precursor with a solvent and adding a nitric acid solution and triethylamine(C6H15N); a step of manufacturing hydroxyapatite sol by mixing ammonium hydroxide(NH4OH) with the mixture after mixing potassium nitrate tetrahydrate(Ca(NO3)2·4H2O) and triethyl phosphate(P(OC2H5)3) with the solvent; a step of mixing a colloidal silica with the prepared titanium dioxide sol and the hydroxyapatite sol; and a step of mixing a germanium aqueous solution with the photocatalytic sol in which the titanium dioxide(TiO2) and the hydroxyapatite are included.

Description

Composite photocatalyst sol and its manufacturing method {PHOTOCATALYST SOL AND MANUFACTURING METHOD THEREOF}

The present invention relates to a photocatalyst sol made of a composite material and a method for manufacturing the same, and more particularly, to a photocatalyst composite material including titanium oxide (TiO ₂ ), hydroxyapatite and germanium (Germanium). Composite photocatalyst sol and its manufacturing method which can be actively used as an environmentally friendly material for surface treatment of various interior and exterior building materials such as tiles and wallpaper through sol type photocatalyst with excellent anti-mildew and air purifying ability .

In general, photocatalyst refers to a substance that receives light and promotes a chemical reaction. When a photocatalyst is irradiated with light energy of more than a band gap energy, electrons and holes are generated and holes are generated. The strong oxidative power of radical (-OH) produced by the photocatalyst causes a photooxidation reaction in which gaseous or liquid organic matter adsorbed on the surface of the photocatalyst is decomposed.

That is, the photocatalyst exhibits catalytic activity by absorbing light energy, and oxidatively decomposes environmental pollutants with the strong oxidizing power generated at this time.

Materials that induce such photocatalytic reactions include TiO ₂ (anatase), TiO _{2 (} rutile), ZrO ₂ , ZnO, V ₂ O ₅ , CdS, GaP, InP, GaAs, BaTiO ₃ , KNbO ₃ , Fe ₂ O ₃ , Ta ₂ O ₅ , WO ₃ , SnO ₂ , Bi ₂ O ₃ , NiO, Cu ₂ O, SiO, SiO ₂ , MoS ₂ , InPb, RuO ₂ , CeO ₂ , Brookite and the like are used. Metals such as Pt, Rh, Ag, Cu, Sn, Ni, Fe, and metal oxides thereof may be added to the photocatalyst.

Among them, titanium oxide (TiO ₂ : anatase) is most used because it is harmless to human body, has excellent photocatalytic activity, excellent corrosion resistance, chemical and biological inertness, and low price.

The titanium oxide absorbs and reacts with ultraviolet rays of 388 nm or less to generate electrons (conductor bands) and holes (gap bands) .At this time, ultraviolet light sources include artificial light such as fluorescent lamps, incandescent lamps and mercury lamps. May be used.

The electrons and holes generated in the reaction are recombined in 9 to 12 seconds, but when contaminants and the like are adsorbed on the surface before recombination, the electrons and holes are decomposed by the electrons and holes.

^{_{TiO 2 + hν → e - +}} h +

^{_{e - + O 2 → O 2}} - radical

h ⁺ + -OH → -OH radical

O ₂ ^- radical + A (organic, bacteria, pollutant) → A

-OH radical + B (organic, bacteria, pollutant) → B

In order to provide a coating having a reaction characteristic of a photocatalyst capable of adsorbing and decomposing contaminants, research on the development of a coating sol containing a photocatalyst (titanium dioxide (TiO ₂ )) has been actively conducted. come.

For example, Korean Patent Application Publication No. 2002-0045856 "sol for cure photocatalyst coating and preparation method thereof", Patent Application Publication No. 2002-0083455 "photocatalyst coating sol having photocatalytic activity and high adsorption at the same time," Patent Publication 2002-009267 "Metal added Highly active photocatalyst manufacturing method of titanium oxide sol ", Patent Publication 2004-0099976" Microencapsulated photocatalyst added sol and its manufacturing method ", Patent Publication 2006-0106519" Highly active photocatalyst sol manufacturing method ", registered patent No. 0825084 "Method for preparing titanium dioxide photocatalyst sol and method for preparing titanium dioxide photocatalyst comprising the same", and the like.

However, since the initial anatase-type titanium oxide photocatalyst is an amorphous structure and can be manufactured only by heat treatment, it can be used where heat treatment of the support such as glass, ceramics, and metals is possible, but it is mainly used as a building material or wallpaper. In addition, the use of wood, plastics had a disadvantage that must be limited.

In addition, the conventional anatase-type titanium oxide photocatalyst including the disclosed techniques is used for chemical reaction by converting light energy into chemical energy, and for the catalytic reaction, it requires light energy of more than the band gap of the titanium dioxide photocatalyst (3.0 ~ 3.2eV). However, since it corresponds to the ultraviolet region, it is not a form capable of effectively absorbing the ultraviolet region, which is mostly less than 5% of the sunlight, which is the visible region, and thus does not solve the disadvantage that its utilization is very low due to its low activity.

In particular, as the hot air of well-being has increased, consumers' attention has been focused on environmentally friendly building materials (wallpaper and tiles), and materials that emit large amounts of far-infrared rays and anions, which are useful for the human body, have emerged. However, because of the difficulty of construction and cost of ocher, it is urgently required to develop a photocatalyst that can actively replace it.

The present invention was created in view of the above-mentioned problems in the prior art, and is solved by using a precursor of titanium oxide (TiO ₂ ) and hydroxyapatite (Hydroxyapatite) to form a sol, and The present invention relates to a photocatalyst composite material which can be easily activated even in the visible light region by adding and mixing germanium.

By utilizing the present invention in the surface treatment of various building interior and exterior materials such as tiles and wallpaper, it is possible to build an environment-friendly residential space with excellent antibacterial, anti-mildew, as well as air purification function by far infrared radiation and anion emission while being excellent in cost. There is a major problem in providing a composite photocatalyst sol and its preparation method.

The gist of the present invention for solving the above problems is as follows.

(1) A method for producing a composite photocatalyst sol containing titanium dioxide (TiO ₂ ) and hydroxyapatite

(a) mixing titanium precursor with a solvent to prepare a titanium dioxide (TiO ₂ ) sol by stirring by adding nitric acid solution and triethylamine (C ₆ H ₁₅ N);

(b) Potassium nitrate tetrahydrate (Ca (NO ₃ ) _{2 ·} 4H ₂ O) and triethyl phosphite (P (OC ₂ H ₅ ) ₃ ) are stirred in a solvent, and ammonium hydroxide (NH ₄ OH) is stirred therein. Preparing a hydroxyapatite sol;

(c) mixing and stirring colloidal silica with the titanium dioxide sol produced by step (a) and the hydroxyapatite sol prepared by step (b); And

(d) Mixing an aqueous germanium solution with a photocatalyst sol containing titanium dioxide (TiO ₂ ) and hydroxyapatite prepared in steps (a), (b) and (c) Method for producing a composite photocatalyst sol (sol) comprising the step of stirring.

(2) The method for producing a composite photocatalyst sol according to the above (1), wherein the solvent is an alcohol solvent.

(3) The method for producing a composite photocatalyst sol according to the above (1), wherein the titanium precursor is titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ).

(4) The method of producing a composite photocatalyst sol (1) according to the above (1), wherein the aqueous germanium solution is prepared by pulverizing germanium ore into an 80-100 mesh size.

(5) 17 wt% to 28 wt% of titanium dioxide (TiO ₂ ) sol, 21 wt% to 38 wt% of hydroxyapatite sol, 5 wt% to 10 wt% of aqueous solution of germanium, colloidal silica Composite photocatalyst sol (Sol) comprising 3 to 9% by weight.

(6) The titanium dioxide (TiO ₂ ) sol is a titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ) and isopropanol ((CH ₃ ) ₂ CHOH) in a ratio of 1: 1 to 1: 3. The composite photocatalyst sol of the above-mentioned (5), characterized in that it comprises.

(7) The hydroxyapatite sol is 0.09 M to 0.15 M of potassium nitrate tetrahydrate (Ca (NO ₃ ) ₂ .4H ₂ O) and 0.059 M of triethylphosphoric acid (P (OC ₂ H ₅ ) ₃ ). Composite photocatalyst sol according to the above (5), characterized in that it comprises ~ 0.09M.

(8) The composite photocatalyst sol according to the above (5), wherein the aqueous germanium solution contains germanium ore having a size of 80 to 100 mesh.

The composite photocatalyst sol according to the present invention can play a role as a more environmentally friendly composite material, and can also cause a photo-oxidation reaction even with light energy in the visible range by the interaction of these components. Very high, antibacterial, anti-mold, excellent air purification function according to far infrared radiation and anion release can be obtained.

The composite material of titanium dioxide (TiO ₂ ), hydroxyapatite and germanium retains the advantages of the existing titanium dioxide-hydroxyapatite and acts as a more efficient composite photocatalyst through synergy with germanium. .

This method is not only good in terms of sensitivity of titanium dioxide (TiO ₂ ) but also affects the photoelectron characteristics, resulting in photovoltaic generation. In particular, the oxidation function is important in the decomposition of organic matter or antimicrobial aspect by the reaction of germanium and titanium dioxide increases the oxidation power.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment according to the present invention.

Composite photocatalyst sol according to the present invention is prepared by using a precursor of titanium dioxide (TiO ₂ ), hydroxyapatite (Hydroxyapatite) to form a sol (Sol) and then adding and mixing germanium (Germanium), etc. Titanium (TiO ₂ ) -Hyroxyapatite maintains the advantages of titanium dioxide (TiO ₂ ) while maintaining the advantages, synergies with germanium (Germanium) through a more efficient composite photocatalyst sol can be produced It is.

To this end, the composite photocatalyst sol according to the present invention is 17 to 28% by weight of titanium dioxide (TiO ₂ ) sol (sol), 21 to 38% by weight of hydroxyapatite (sol), aqueous solution of germanium (Germanium) 5 It consists of -10 weight%, a binder 3-9 weight%, and balance water .

At this time, titanium dioxide is a photocatalyst compound for improving the efficiency of the reaction in the presence of light, considering the heavy metals, activity and the like, is stable because there is no photo-corrosion, and biologically and chemically inert.

Titanium dioxide (TiO ₂ ) is prepared in the form of a sol using a titanium dioxide precursor, the titanium dioxide (TiO ₂ ) sol (17) to 28% by weight in the total composite photocatalyst sol (sol) It is preferable to add a catalyst, which is less than 17% by weight, the activity of the catalyst is lowered, when it exceeds 28% by weight, the dependence of light is increased, the efficiency of the photooxidation reaction in the absence of light It is because it is preferable to limit to the said range since it falls rapidly.

On the other hand, the hydroxyapatite (Hydroxyapatite) is a major component of living hard tissues such as teeth and bones, and is easy to ion exchange with various cations and anions, and has high biocompatibility and adsorption characteristics.

That is, the hydroxyapatite is a substance that constitutes 65% of bone and 95% of tooth enamel and has excellent adsorption of proteins and the like, and thus can adsorb bacteria, viruses, ammonia, nitrogen oxides, aldehydes, and the like. Has suitable properties.

For this reason, the hydroxyapatite has been applied in a wide range of fields such as medical materials such as artificial bones and artificial roots, adsorbents for chromatography, chemical sensors, ion exchangers, catalysts, and the like. It also has the ability to specifically adsorb organic substances such as proteins.

The hydroxyapatite as described above is prepared in the form of a sol, and hydroxyapatite is preferably 21% to 38% by weight of the composite photocatalyst sol, which is premised on the hydroxyapatite sol. If the amount is less than 21% by weight, the amount is so weak that the adsorptivity of the organic material is lowered. If it exceeds 38% by weight, the dependence by adsorption is increased and the efficiency of light is lowered. Because.

In addition, germanium (Germaniun), which is one of the included substances, is an off-white mineral, and emits far infrared rays, and absorbs toxic substances to make other substances which are not toxic after chemically bonding, and also has an anion-releasing effect. This is a well known fact.

Such germanium (Germaniun) is a part of the silicate having a mass number of 76 is substituted by some of the silicon, and is also a material having an off-white cubic system and diamond structure present in sulfide or coal or coal, currently applied by using germanium (Germaniun) The technology has been applied to anticancer drugs, burn treatments, vaginal cleansers, various skin diseases and eye diseases.

In particular, the discovery of germanium veins in the domestic situation is growing interest in the utilization of germanium, technology development is progressing in various fields as shown in Table 1 below.

 Kinds  Symbol  Usage  water  condition  Remarks  germanium  Ge  Semiconductor, skin  99.99%  Incoat  Discover C. Winkler in Germany  Organic germanium  Ge  For food and medicine  42.8%  powder  Colorless, odorless, slightly acidic, well watered (water soluble)  Germanium dioxide GeO ₂  Industrial  69.42%  powder  Used for industrial purposes, deadly in human use, not recording in water

As shown in Table 1, germanium-related industries are being led by the semiconductor industry, but with increasing environmental concerns, their use in environmental and health uses is increasing rapidly.

In the present invention, the germanium (Germanium) through the antimicrobial, anti-fungal, that is, it is necessary to configure the appropriate particle size in order to secure a strong oxidizing power.

To this end, the germanium (Germanium) is preferably mixed with titanium dioxide (TiO ₂ ) to have a particle size of 80-100 mesh in order to have at least 95% antimicrobial activity.

This is the conditions shown in Figure 1, using a germanium ore, pulverized it and sieved by the mesh, classify, and by performing an E. coli (E. coli) experiment for each mesh to compare and analyze the efficiency, 80-100 mesh When it is confirmed that the removal rate of E. coli is more than 95% as shown in the graph of Figure 2 because the germanium (Germanium) having a particle size of the above range is most suitable for the present invention.

That is, as shown in the graph, the efficiency of E. coli removal is not significantly different under the conditions of 80-100 mesh or less, so selecting the germanium gemstone processing condition as 80-100 mesh reduces the steps of the manufacturing process and saves the cost. to be.

In addition, in order to obtain a synergistic effect with titanium dioxide (TiO ₂ ), the germanium (Germanium) should be prepared in an aqueous solution to have a composition of 5 to 10% by weight.

This is not only a good solution in terms of the sensitivity of titanium dioxide (TiO ₂ ) but also affects the optoelectronic properties, which can generate photovoltaic power. In particular, germanium and titanium dioxide are important for the oxidation function in terms of organic decomposition or antibacterial. This is because the oxidizing power can be further increased by the reaction with (TiO ₂ ).

In other words, when germanium and titanium dioxide (TiO ₂ ) are linked, as in the balanced half-reaction below, the electrons of titanium dioxide (TiO ₂ ) are taken away to create free holes and thus more free holes Due to this, the oxidizing power is increased and the reactivity at a wider range of wavelengths can be obtained than the composition of the conventional titanium dioxide (TiO ₂ ) -hydroxyapatite, and thus the photocatalyst according to the present invention can be used only in the ultraviolet region. Rather than reacting, it is possible to easily perform photoreaction in the visible light range, so that the range of application can be increased significantly.

Balanced half - reaction

Ge ₂ ⁺ + 2e ^- Ge (s)

GeO ₂ (s) + 4H ⁺ + 2e ^- Ge ^{2 +} + 2H ₂ O

GeO ₂ (s) + 4H ⁺ + 4e ^- Ge + 2H ₂ O

H ₂ GeO ₃ + 4H ⁺ + 4e ^- Ge (s) + 3H ₂ O

GeO (s) + 2H ⁺ + 2e ^- Ge (s) + H ₂ O

Therefore, in the present invention, the germanium should be prepared in the form of an aqueous solution and added at 5-10% by weight. If it is added below 5% by weight, the effect of far-infrared radiation or anion emission is weak, and if more than 10% by weight is added, the cost Since burden increases rapidly, it is preferable to add in the said range.

On the other hand, the binder is to increase the bonding force between the components when mixing each component, it is preferable to use an inorganic binder containing SiO ₂ .

This is because the inorganic binder does not interfere with the properties of the light and matte catalysts, the sterilization and the antibacterial action of the composition according to the present invention.

Colloidal silica is particularly preferred as such an inorganic binder because it is excellent in binding, heat resistance, film formation and adsorption properties.

Furthermore, since the inorganic binder already contains Ca in hydroxyapatite, Ca does not need to be added in excess because it acts as a binder to some extent, and 3-9 weight in consideration of the hydroxyapatite. It is preferable to add in the range of%.

Finally, the remaining 15 to 54% by weight of water can be made into the sol form by mixing with the above-mentioned ingredients.

The photocatalyst sol according to the present invention having such a composition can be prepared by the following method.

As shown in Figure 3, to make a composite photocatalyst sol according to the present invention is first subjected to a germanium (Germanium) aqueous solution manufacturing step (S100).

At this time, the germanium (Germanium) aqueous solution manufacturing step (S100) includes a process of grinding the germanium (Germanium) ore to have a specific particle diameter (80 ~ 100mesh), adding water to the crushed germanium powder and stirring.

That is, the germanium (Germanium) ore is prepared for the aqueous solution of germanium is then pulverized in a rotary kiln of 200-250 ℃, the particle size of the germanium (Germanium) at the time of pulverization is to be 80-100 mesh as described above .

Thereafter, germanium and water are mixed at a ratio of 1:10, and then stirred at a low speed for about 3-5 hours to make an aqueous germanium solution.

Here, the reason why the germanium ore is pulverized in the rotary kiln maintained at 200-250 ° C. is because when the germanium ore is crushed at less than 200 ° C., the pore formation problem occurs, and if it is above 250 ° C., there is a problem of cracking. to be.

And, there is carried out the titanium dioxide (TiO ₂₎ sol production phase (S200), which is a method of producing titanium dioxide (TiO ₂₎ sol prepared from a precursor of titanium dioxide (TiO _2).

Here, the titanium dioxide (TiO ₂ ) sol is a mixture of Titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ) and Isopropanol ((CH ₃ ) ₂ CHOH) in a weight ratio of 1: 1 or 1: 3 Next, the mixture was stirred for 0.5 hours, and then nitric acid (HNO ₃ ) of 0.5-2 M was added, followed by stirring for 12-36 hours. 2 ~ 5M of Triethylamine (C ₆ H ₁₅ N) was added and mixed and stirred for 6 ~ 18 hours to form N-TiO ₂ To prepare a sol.

At this time, each component added in the titanium dioxide sol manufacturing process is added to the solvent Titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ) precursor Isopropanol ((CH ₃ ) ₂ CHOH) and triethylamine ( C ₆ H ₁₅ N) is added and mixed.

On the other hand, hydroxyapatite (Hydroxyapatite) should also be prepared in the sol (sol) type, hydroxyapatite sol manufacturing step (S300) is 100ml of ethanol and 0.098 ~ 0.15M calcium nitrate tetrahydrate (Ca (NO ₃ ) ₂ · 4H ₂ O), 0.059-0.09 M triethylphosphoric acid (P (OC ₂ H ₅ ) ₃ ), and 1 L of water were mixed with each other, and then stirred for 1 to 2 hours, followed by ammonium hydroxide (NH ₄ OH) 90 Prepared by adding ~ 100ml and stirring again for 3-6 hours.

At this time, each component added during the hydroxyapatite sol preparation is mixed by adding calcium nitrate tetrahydrate (Ca (NO ₃ ) ₂ · 4H ₂ O) and triethylphosphoric acid (P (OC ₂ H ₅ ) ₃ ) precursor. NH ₄ OH is added and mixed for pH adjustment.

Thus prepared germanium solution, titanium dioxide sol and hydroxyapatite sol, respectively, 5-10% by weight of germanium solution, 17-28% by weight titanium dioxide (TiO ₂ ) sol, hydroxyapatite (Hydroxyapatite) After mixing in a weight ratio of 21 to 38% by weight of sol, water is mixed and in that state is added to 3 to 9% by weight of colloidal silica as a binder and low-speed stirring for 1.5 to 3 hours composite photocatalyst according to the present invention The sol is complete.

The composite photocatalyst sol prepared through these steps is applied to the surface of various building interior and exterior materials including wallpaper, tile, etc. by spraying, rolling, etc., so that it can cause photo-oxidation reaction using only light energy in the visible region. In addition, it can be used as an eco-friendly material that provides antibacterial and antifungal properties as well as air purification function according to far infrared radiation and anion emission.

Hereinafter, an Example is described.

EXAMPLE

Preparation as described above to have a composition range of the following Table 2 to determine whether the photoacid reaction occurs in the visible light region and the antimicrobial, anti-fungal and far infrared radiation of the composite photocatalyst sol according to the present invention After the photocatalyst sol was made through the method, a plurality of specimen wallpaper having a size of 4 cm × 4 cm × 4 cm were sprayed and applied to a thickness of 0.2 μm, and then the efficacy thereof was confirmed.

At this time, the particle size of titanium dioxide is 21nm, hydroxyapatite particle size of 15㎛, germanium 90 mesh size, by adding colloidal silica as a binder at low speed for 1 hour at a speed of 180rpm by photocatalyst according to the present invention A suspension was made.

In addition, for comparison, a general wall paper (traditional material) not coated with a photocatalyst and a wallpaper (comparative material) coated with a conventional titanium dioxide photocatalyst were further prepared, and the experimental results are shown in Table 2.

In order to check the antimicrobial activity, E. coli was inoculated on an agar medium and incubated at 37 ° C. for 24 hours, and then sprayed on the specimen wallpaper (inventive material 1, 2, 3) and the conventional and comparative materials by the same amount. It was left for time.

Subsequently, after 24 hours, the same amount of distilled water was sprayed onto the invention materials 1,2,3, the conventional material and the comparative material, respectively, and the E. coli grown from the test piece was extracted with distilled water.

The percentage reduction of E. coli remaining in the distilled water extracted from these was then calculated and is very good if it exceeds 95%, good for 93-95%, normal for less than 90-93%, less than 90% It was determined that the defect was bad.

In addition, in order to confirm the antifungal efficacy, Aspergillus nigro, Penicillium citranum and ketoneium globosome according to JIS Z 2911-2001 test method at the temperature of 28 ℃ invention materials 1, 2, 3, Antifungal experiments were performed on the conventional and comparative materials, respectively, and the results of the fungus were confirmed and the results are shown in Table 2.

In addition, in order to confirm the efficacy of far-infrared radiation TSS-5XN (far-infrared emissivity measuring instrument: detection method of the amount of radiation energy according to infrared radiation from a constant temperature radiation source, measurement wavelength: 2-22㎛, measurement range: emissivity 0.00-1.00, measurement accuracy: Insulation material using ± 0.01 or less, measuring area: φ15 mm, sample temperature: 10-40 ° C, output: 0-0.1V: 0-1V, display: LED digital display, power / power: AC100V, 50-60Hz Far-infrared radiation experiments were carried out for each of 1,2,3, conventional and comparative materials, and the results are shown in Table 2.

Furthermore, in order to confirm the effect of releasing negative ions, an ion tester manufactured by Eco-Holistic Co., Ltd. is directly grounded to each of Inventive Materials 1, 2, 3, Conventional Materials, and Comparative Materials to read the numerical value displayed on the instrument panel. It was confirmed whether the negative ions generated, the results are shown in Table 2.

All percentages shown in Table 2 below are% by weight.

In addition, "HAp" shown in Table 2 below means hydroxyapatite, and the symbols indicated are ◎: very good, ○: excellent, Δ: normal, and ×: poor.

 division  Ingredient composition  Antimicrobial activity  Antifungal  Far infrared radiation  Negative ion release TiO ₂ Sol  HAp Sol  Ge aqueous solution  bookbinder  water  Conventional  -  -  -  -  -  ×  ×  ×  ×  Comparative material  100%  -  -  -  -  △  △  ×  ×  Invention 1  25%  27%  5%  6%  37%  ◎  ◎  ○  ○  Invention 2  26%  25%  6%  6%  37%  ◎  ◎  ○  ○  Invention 3  28%  22%  10%  6%  34%  ◎  ◎  ◎  ◎

On the other hand, in order to confirm the activity of the photooxidation reaction, 900mm in length, T5-21W fluorescent lamp was installed and used as a light source to check whether the photoacidification activity.

As a result of directly irradiating near ultraviolet and visible light to comparative materials and invention materials 1, 2 and 3 including conventional materials, there was no reaction in conventional materials, and photooxidation reaction occurred only in near UV irradiation in comparative materials. Inventive materials 1, 2, and 3, the photooxidation reaction occurred in both near ultraviolet light and visible light.

Based on the results as described above, the photocatalyst according to the present invention is much more active and inexpensive than the conventional photocatalyst in which only titanium dioxide is the main component, and also has excellent antibacterial and antifungal properties, and far-infrared radiation and anion emission. Through air purifying function was confirmed through.

1 is an experimental schematic diagram for determining the particle diameter of germanium.

Figure 2 is a graph comparing the E. coli removal efficiency of each condition according to FIG.

Figure 3 is a schematic diagram of a composite photocatalyst sol manufacturing step using titanium dioxide (TiO ₂ ), hydroxyapatite (Hydroxyapatite), germanium.

Figure 4 is a composite photocatalyst sol manufacturing flow chart using titanium dioxide (TiO ₂ ), hydroxyapatite (Hydroxyapatite), germanium.

Claims (8)

As a method of manufacturing a composite photocatalyst sol containing titanium dioxide (TiO ₂ ) and hydroxyapatite, (a) mixing titanium precursor with a solvent to prepare a titanium dioxide (TiO ₂ ) sol by stirring by adding nitric acid solution and triethylamine (C ₆ H ₁₅ N); (b) Potassium nitrate tetrahydrate (Ca (NO ₃ ) _{2 ·} 4H ₂ O) and triethyl phosphite (P (OC ₂ H ₅ ) ₃ ) are stirred in a solvent, and ammonium hydroxide (NH ₄ OH) is stirred therein. Preparing a hydroxyapatite sol; (c) mixing and stirring colloidal silica with the titanium dioxide sol produced by step (a) and the hydroxyapatite sol prepared by step (b); And (d) Mixing an aqueous germanium solution with a photocatalyst sol containing titanium dioxide (TiO ₂ ) and hydroxyapatite prepared in steps (a), (b) and (c) Method for producing a composite photocatalyst sol (sol) comprising the step of stirring. The method of claim 1, wherein the solvent is an alcohol-based solvent. The method of claim 1, wherein the titanium precursor is titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ). The method of claim 1, wherein the aqueous solution of germanium is prepared by pulverizing the germanium gemstone to the size of 80 ~ 100mesh. 17 wt% to 28 wt% of titanium dioxide (TiO ₂ ) sol and 21 wt% to 38 wt% of hydroxyapatite sol, 5 wt% to 10 wt% of aqueous solution of germanium, 3 wt% of colloidal silica Composite photocatalyst sol (Sol) comprising from 9% by weight. The method of claim 5, wherein the titanium dioxide (TiO ₂ ) sol is a titanium tetraisopropoxide (Ti (OCH (CH ₃ ) ₂ ) ₄ ) and isopropanol ((CH ₃ ) ₂ CHOH) 1: 1 to 1: 3 Composite photocatalyst sol (Sol) characterized in that it comprises at a ratio of. The method of claim 5, wherein the hydroxyapatite sol comprises potassium nitrate tetrahydrate (Ca (NO ₃ ) ₂ .4H ₂ O) 0.09M to 0.15M and triethylphosphoric acid (P (OC ₂ H ₅ ) ₃ ) Composite photocatalyst sol (sol) comprising a 0.059M ~ 0.09M. The composite photocatalyst sol according to claim 5, wherein the aqueous germanium solution contains germanium ore having a size of 80 to 100 mesh.

Images