KR101677842B1 - Multifunctional Cu-TiO2-PU having both photocatalyst and adsorbent activity and manufacturing method thereof - Google Patents

Abstract

The present invention relates to a multifunctional copper-titanium dioxide / polyurethane having both functions as a photocatalyst and an adsorbent, and a method for producing the same. More specifically, the titanium dioxide thin film is fixed on a polyurethane support having a porous honeycomb structure, Characterized in that copper (Cu) is doped on the thin film. The present invention relates to a multi-functional copper-titanium dioxide / polyurethane and a method for producing the same. The multifunction copper-titanium dioxide / polyurethane according to the present invention can be used as an adsorbent by using a porous polyurethane as a support and can be chemically bonded to titanium dioxide by electronic characteristics, so that the titanium dioxide thin film is not easily peeled off, Is doped to lower the band gap energy of titanium dioxide to thereby exhibit excellent photocatalytic activity in the visible light range including ultraviolet rays and can be activated even in the case of visible light such as a fluorescent lamp or a lamp in the room. It is less economical to use. In addition, by using photo-deposition in copper doping, the doping process does not affect the bonding between the titanium dioxide and the polyurethane, and mass production and regeneration are possible, so that it can be used semi-permanently. Therefore, in place of the conventional adsorbent and photocatalyst, It can be useful for purification.

Description

TECHNICAL FIELD The present invention relates to a multifunctional copper-titanium dioxide-polyurethane having both functions of a photocatalyst and an adsorbent, and a method for producing the same.

The present invention relates to a multifunctional copper-titanium dioxide / polyurethane having both photocatalyst and adsorbent functions and a process for its preparation.

At the moment, new buildings or newly-built houses in domestic apartments are tinged with eyes, feel dizzy, suddenly become breathless, and cause respiratory diseases such as asthma and atopic skin inflammation In recent years, the possibility of carcinogenesis due to harmful gas such as formaldehyde, volatile organic compounds, carbonic acid gas,

Indoor air purification regulations have been introduced to eliminate Sick House Syndrome and apartments will be enacted in accordance with the air pollution level.

In Korea, the total amount of volatile organic compounds (VOC) in indoor air is 1.6mg / ㎥, and the standard of advanced countries such as Europe and Japan is 0.4㎎ / ㎥. It is managed by strict standards.

In order to reduce such VOC, a photocatalyst is used.

The photocatalyst refers to a catalyst that exhibits activity by light energy in the sense of combining photochemistry and catalyst. As the environmental pollution increases, it is one of the most popular technologies among the many processes for treating pollutants.

In particular, since the photocatalyst has a strong oxidizing and reducing power on the surface of the photocatalyst when activated, it can be applied to various fields, and has excellent ability of decomposing organic matters and has a function of purifying the atmosphere and removing harmful substances. The most typical characteristic of the photocatalyst is the self-cleansing ability.

Materials that can be used for photocatalysts include anatase type titanium dioxide, rutile type titanium dioxide, zinc oxide (ZnO), cadmium sulfide (CdS), zirconium oxide (ZrO ₂ ), vanadium oxide (V ₂ O ₂ ). Tungsten oxide (WO ₃ ), and perovskite-type composite metal oxide (SrTiO ₃ ).

However, the semiconductor material that can be used for the actual photocatalytic reaction must first be optically active and free of photo-curing. It must also be biologically and chemically inert, able to use visible light or ultraviolet light, and economically inexpensive. Titanium is the ninth most element in the earth's crust, and white pigments and white paints commonly used in cosmetics are mainly made of titanium dioxide. Titanium dioxide which does not react by light if possible is used as the pigment, but titanium dioxide which has enhanced photoreaction property is used for a photocatalyst application product such as an air purifier. In addition, titanium dioxide is abundant in resources, so its price is cheap, its durability and abrasion resistance are excellent as a photocatalyst, and even if it is disposed of as safe and nontoxic, there is no concern about secondary pollution. It is one of the products of Nano Industry. In particular, considering the conditions and activity of the photocatalyst, it can be used semi-permanently because it does not change even if it receives light. It has higher oxidizing power than chlorine (Cl ₂ ) and ozone (O ₃ ) Titanium oxide (TiO ₂ ) which can be decomposed with water is widely used as a typical photocatalyst material.

The biggest advantage of TiO ₂ is that it is chemically stable, harmless to the human body, and cheaper than other materials. However, such a photocatalyst requires a light energy of more than a certain energy in order to cause a photoreaction. Particularly, since pure TiO ₂ photocatalyst can not be used only by ultraviolet ray, efficiency is low and it is difficult to be practically used. It is a weak level compared to the natural purification rate, and there are technical limitations.

Accordingly, development of a TiO ₂ -based photocatalyst capable of being activated in a visible light region by lowering the band gap of TiO ₂ is urgently required. As described above, the TiO ₂ photocatalyst acts only in the ultraviolet region with an energy band gap of 3.0 to 3.2 eV, which is inefficient. Therefore, in order to increase the efficiency, a titanium dioxide-based photocatalyst which works in the visible light region is also desired.

In order to develop a titanium dioxide-based photocatalyst which exhibits excellent efficiency in the visible light region, there is a method of doping an anatase titanium dioxide with ions of metals such as Fe, V and Pt (JP-A-1997-192496, 2007-0083259 Korean Patent Publication No. 2002-0082633). However, when the metal ions are doped as described above, various defects occur due to the decomposition reaction due to light and charge imbalance, and the performance is not sufficient. Another method is to make a TiO ₂ -X type by doping an anatase titanium dioxide with a nonmetal ion such as C or N or an anion (X) (JP-A-1999-333302, 2001-205103, 2002- 095976, 2005-213123). In this case, there is a problem that the catalyst activity is not so high. In particular, expensive equipment such as an electric furnace is required in the production process, and the reaction temperature and the control condition to make the reactivity excellent are difficult.

Therefore, there is a desperate need to develop a titanium dioxide catalyst production technology which can be easily produced while exhibiting excellent optical resolution in the visible light region.

In recent years, attempts have been made to develop materials incorporating adsorption performance in photocatalysts for the rapid removal of volatile organic compounds (VOC).

Several approaches have been taken to deposit TiO ₂ powders on substrates such as glass films, glass fibers, activated carbons and graphene films to incorporate adsorptive performance in photocatalysts as well as to broaden the photocatalytic applications of other utility systems [SW Verbruggen, S. Deng, M. Kurttepeli, DJ Cott, PM Vereecken, S. Bals, JA Martens, C. Detavernier, S. Lenaerts, Applied Catalysis B: Environmental, 160-161 (2014) 204-210; YL Pang, S. Lim, HC Ong, WT Chong, Applied Catalysis: General, 481 (2014) 127-142.]. However, most deposition methods deposit TiO ₂ on the substrate surface only by physical bonding, and the physical bond forms a weak bond between TiO ₂ and the substrate. Therefore, there is a problem that TiO ₂ can be easily peeled off from the substrate in the subsequent use.

Accordingly, the present inventors have found that even when a visible light having a lower energy than ultraviolet rays is received, the photocatalytic action can be performed, the efficiency of the photocatalyst can be enhanced, the adsorption function can be performed at the same time, the titanium dioxide thin film is strongly fixed on the support, As a result of research to develop a novel photocatalyst having high removal efficiency of organic compound (VOC), titanium dioxide was chemically deposited on a honeycomb polyurethane (PU), and copper (Cu) Was doped in titanium dioxide, exhibited excellent photocatalytic activity in the visible light region and exhibited an adsorption performance at the same time, and completed the present invention.

1. Japanese Patent Application Laid-Open No. 1997-0192496 2. Japanese Patent Application Laid-Open No. 2007-0083259 3. Korean Patent Publication No. 2002-0082633

It is an object of the present invention to provide a multifunctional substance having both functions of a photocatalyst and an adsorbent.

Another object of the present invention is to provide a method for producing the above multifunctional substance.

In order to accomplish the above object, the present invention provides a method for producing a photocatalyst and an adsorbent, wherein the titanium dioxide thin film is fixed on a polyurethane support having a porous honeycomb structure, and the titanium dioxide thin film is doped with copper (Cu) Has a multifunctional copper-titanium dioxide / polyurethane.

In addition, preferably, the titanium dioxide thin film can be fixed on the polyurethane support by C-Si-O-Ti bonds generated by using silicon as a bridge element.

In addition, preferably, the copper (Cu) can be doped on the titanium dioxide thin film by photo-deposition.

Preferably, the copper (Cu) may be doped on the titanium dioxide thin film at a weight fraction of 1 to 10%.

In addition,

(a) introducing an isocyanate group (NCO) to the surface of the polyurethane to activate the polyurethane;

(b) silanizing the titanium;

(c) immersing an activated polyurethane containing an NCO group in a silanized titanium solution, followed by calcination to produce a titanium dioxide thin film fixed on the polyurethane; And

(d) doping copper (Cu) on a titanium dioxide thin film by photo-deposition to produce a multi-functional copper-carbon dioxide / polyurethane. .

Preferably, the step (a) is a step in which the polyurethane is placed in a mixed solution of an organic solvent, toluene 2,4-diisocyanate (TDI) and anhydrous triethylamine and heated at 50-70 ° C for 1-2 hours During .

Preferably, the step (b) may be performed by reacting a solution of titanium tetraisopropoxide (TTIP) in an organic solvent with a solution of? -Aminopropyltriethoxysilane (APTES) in an organic solvent to silanize titanium .

Preferably, the calcination of step (c) may be carried out at 200-250 占 폚 for 1-3 hours.

The multifunction copper-titanium dioxide / polyurethane according to the present invention can be used as an adsorbent by using a porous polyurethane as a support and can be chemically bonded to titanium dioxide by electronic characteristics, so that the titanium dioxide thin film is not easily peeled off, Is doped to lower the band gap energy of titanium dioxide and exhibits an excellent photocatalytic activity in the visible light range including ultraviolet rays and can be activated even to weak visible light such as a fluorescent lamp or a lamp in the room. Therefore, when used as a photocatalyst, It is economical to use. In addition, by using photo-deposition in copper doping, the doping process does not affect the bonding between the titanium dioxide and the polyurethane, and mass production and regeneration are possible, so that it can be used semi-permanently. Therefore, in place of the conventional adsorbent and photocatalyst, It can be useful for purification.

Figure 1 shows the FTIR spectra of the pure PU, PU activated and TiO ₂ / PU produced by the Comparative Examples and the embodiment of the present invention.
Figure 2 shows a high-resolution XPS spectrum of Cu 2p in Cu-TiO ₂ / PU prepared according to one embodiment of the present invention.
Figure 3 is a SEM and (D) of the _{PU (A), TiO 2 /} PU (B), and one _{Cu-TiO 2 / PU (C} ) according to an embodiment according to Comparative Example of the present invention Cu-TiO ₂ / The mapping of Cu and Ti in the PU is shown.
Figure 4 shows the UV-Vis absorption spectra of PU, TiO ₂ / PU and Cu-TiO ₂ / PU prepared according to one comparative example and one embodiment of the present invention.

Hereinafter, the present invention will be described in detail.

The present invention provides a multifunctional copper-titanium dioxide / polyurethane having both photocatalyst and adsorbent functions.

The multifunctional copper-titanium dioxide / polyurethane according to the present invention is characterized in that a titanium dioxide thin film is fixed on a polyurethane support having a porous honeycomb structure and copper (Cu) is doped on the titanium dioxide thin film.

In the polyfunctional copper-titanium dioxide / polyurethane according to the present invention, the polyurethane (PU) plays a role of a substrate or a support and is excellent in adsorption because it is a porous material having a pore size of 100-300 μm. It is also possible to chemically bond with titanium dioxide through surface modification.

In the multifunctional copper-titanium dioxide / polyurethane according to the present invention, the titanium dioxide (TiO ₂ ) is a main material of the photocatalyst and has excellent durability and abrasion resistance, is chemically stable, harmless to the human body, However, since the pure TiO ₂ photocatalyst can not be used only in ultraviolet rays, the efficiency is low and it is difficult to put it into practical use. In order to compensate for this, in the present invention, copper is doped on the titanium dioxide thin film to lower the band gap energy of titanium dioxide, thereby exhibiting excellent photocatalytic activity in the visible light range including ultraviolet rays.

Accordingly, the copper-titanium dioxide / polyurethane according to the present invention is a multifunctional substance capable of simultaneously performing the function of the adsorbent and the photocatalytic function.

In the multifunctional copper-titanium dioxide / polyurethane according to the present invention, physical bonding is mainly used for depositing TiO ₂ powder on a substrate such as a glass thin film, a glass fiber, an activated carbon and a graphene film, The bond forms a weak bond between the TiO ₂ and the substrate, so there is a problem that TiO ₂ can easily peel off from the substrate during the subsequent use. However, the copper-titanium dioxide / polyurethane according to the present invention can be chemically bonded to the titanium dioxide thin film by the C-Si-O-Ti bond formed through surface modification by using the polyurethane support as a bridge element TiO ₂ is not readily peeled off during use, and thus can exhibit photocatalytic activity semi-permanently.

At this time, the copper (Cu) is preferably doped on the titanium dioxide thin film by photo-deposition. Conventionally, methods such as sol-gel, hydrothermal, ion-exchange, and chemical vapor deposition have been used to dope a metal into a TiO ₂ substrate, If these methods are used to dope the metal into the TiO ₂ immobilized on the polyurethane, it can cause adverse effects on the binding of the TiO ₂ to the polyurethane due to harsh environmental conditions such as pH, temperature and pressure.

In the multifunctional copper-titanium dioxide / polyurethane according to the present invention, the copper (Cu) is preferably doped on the titanium dioxide thin film in a weight fraction of 1 to 10%. If the doping amount of copper is less than 1 wt%, there is a problem that the photocatalytic activity in the visible light region is insufficient. If the doping amount is more than 10 wt%, the doping effect may not be sufficient.

In addition,

(a) introducing an isocyanate group (NCO) to the surface of the polyurethane to activate the polyurethane;

(b) silanizing the titanium;

(c) immersing an activated polyurethane containing an NCO group in a silanized titanium solution, followed by calcination to produce a titanium dioxide thin film fixed on the polyurethane; And

(d) doping copper (Cu) on a titanium dioxide thin film by photo-deposition to produce a multi-functional copper-carbon dioxide / polyurethane. .

First, step (a) is a step of activating the polyurethane.

In this step, the activation of the polyurethane can be carried out through a method commonly used in the art. In one embodiment, the polyurethane is placed in a mixed solution of an organic solvent, toluene 2,4-diisocyanate (TDI) and anhydrous triethylamine, and the reaction is carried out at 50 to 70 ° C for 1 to 2 hours under an inert gas to obtain poly The isocyanate group (NCO) may be introduced into the urethane surface to activate it, but the present invention is not limited thereto.

The organic solvent may be toluene, benzene, n-hexane, or the like.

Next, step (b) is a step of silanizing titanium.

The silanization step of the titanium may also be carried out by a method commonly used in the art. In one embodiment, as shown in Scheme 1 below, a solution of γ-aminopropyltriethoxysilane (APTES) in an organic solvent is reacted with a solution of titanium tetraisopropoxide (TTIP) in an organic solvent to silanate the titanium But is not limited thereto.

The organic solvent may be toluene, benzene, n-hexane, or the like.

<Reaction Scheme 1>

(In the above Reaction Scheme 1, R ₁ and R ₂ are C _{1 -4} linear or branched alkyl)

Next, step (c) is a step of producing a titanium dioxide thin film fixed on the polyurethane.

In this step, an activated polyurethane containing an NCO group can be immersed in a silanized titanium solution and then calcined to produce a titanium dioxide thin film chemically immobilized on the polyurethane, as shown in Reaction Scheme 2 below.

<Reaction Scheme 2>

(Wherein R ₁ and R ₂ are C _{1 -4} straight-chain or branched alkyl)

In the conventional method, the titanium dioxide thin film is fixed to the substrate by physical bonding, thereby easily peeling off during use. However, in the method according to the present invention, the titanium dioxide thin film is strongly fixed to the polyurethane through chemical bonding, There are features that do not.

Here, the calcination may be carried out at 200-250 占 폚 for 1-3 hours in one embodiment.

Next, step (d) is a step of doping copper (Cu) on the titanium dioxide thin film.

In this step, the deposition of copper is performed using a photo-deposition method. In this case, the amount of doped copper is preferably doped with a weight fraction of 1 to 10% Cu for an excellent photocatalytic germicidal effect. If the concentration is out of the above range, there is a problem that the photocatalytic sterilization efficiency is deteriorated.

In this step, the doping process does not affect the bonding between the titanium dioxide and the polyurethane by using photo-deposition during copper doping.

The multi-functional copper-titanium dioxide / polyurethane thus prepared can be used as an adsorbent by using porous polyurethane as a support, and can be chemically bonded to titanium dioxide by electronic characteristics, so that the titanium dioxide thin film is not easily peeled off, Doping to lower the band gap energy of titanium dioxide and to exhibit excellent photocatalytic activity in the visible light range including ultraviolet rays and to be activated even in the case of visible light such as a fluorescent lamp or a lamp in the room, It is economical. In addition, by using photo-deposition in copper doping, the doping process does not affect the bonding between the titanium dioxide and the polyurethane, and mass production and regeneration are possible, so that it can be used semi-permanently. Therefore, in place of the conventional adsorbent and photocatalyst, It can be useful for purification.

Hereinafter, the present invention will be described in more detail with reference to Examples. These examples are for further illustrating the present invention, and the scope of the present invention is not limited to these examples.

< Example  1> Multifunction Copper - Titanium Dioxide / Polyurethane Photocatalyst  Produce

<1-1> Pure polyurethane ( PU ) Activation

The pure honeycomb PU foam was washed in toluene and ethanol solution, respectively, under strong ultrasonic treatment conditions for 20 minutes. The washed PU was dried under vacuum at 40 占 폚 for 2 hours and then placed in a mixed solution of 85% toluene, 10% toluene 2,4-diisocyanate (TDI) and 5% anhydrous triethylamine. To introduce an isocyanate group (NCO) on the surface of the PU, the solution containing the PU was heated to 60 DEG C for 1 hour under nitrogen as a protective gas with constant stirring. After this process, the PU containing the isocyanate group (activated PU) was repeatedly washed with toluene and dried in a nitrogen gas at 60 DEG C for 4 hours.

<1-2> Titanium Silanization

To prepare the titanium silanization process, first, a solution of titanium tetraisopropoxide (TTIP) was slowly added dropwise to a flask containing toluene under stirring conditions to obtain a 5 V% solution of TTIP in toluene. Second, a toluene solution containing the same volume of 4 V% gamma -aminopropyltriethoxysilane (APTES) was added to the flask. The mixture flask was agitated continuously for 1 hour and then held in an oven at 4O &lt; 0 &gt; C for 4 hours to silanate the titanium. The final product was a colloidal solution of titanosiloxane.

<1-3> PU  On TiO ₂  deposition

Next, the activated PU containing the NCO group was immersed in a solution of colloidal titanosiloxane at 40 DEG C for 1 hour.

After immersion, the TiO ₂ coated on the PU was slowly washed with distilled water. Finally, the TiO ₂ coated on the PU was dried at 80 ° C for 2 hours and calcined in protective nitrogen gas at 200 ° C for 2 hours to obtain TiO ₂ fixed on the PU.

<1-4> PU  Fixed on TiO ₂  Within Cu Photo-deposition

The Cu-TiO ₂ / PU photocatalyst was synthesized by slowly dropping 0.1 M Cu (NO ₃ ) ₂ solution onto the TiO ₂ coated on the PU after the immersion process. Then, the Cu-TiO ₂ / PU was irradiated with UV light (60 W) for 5 hours and calcined in a protective nitrogen gas at 200 ° C for 2 hours to obtain a Cu-TiO ₂ / PU photocatalyst.

< Comparative Example  1>

Pure PU was used as a comparative example.

< Comparative Example  2>

Activated PU was used through the process of <1-1> of Example 1.

< Experimental Example  1> FTIR  analysis

In the copper-titanium dioxide / polyurethane catalyst according to the present invention, FTIR analysis was conducted to determine whether titanium dioxide was successfully deposited on the polyurethane, and the results are shown in FIG.

Figure 1 shows the FTIR spectra of pure PU, PU activated and TiO ₂ / PU. The FTIR bands and their designated vibrations are shown in Table 1 below.

The FTIR spectrum shows that the urethane group (-NH-CO-O-) containing NH, CN, C = O and CO bonds in pure PU was successfully converted to an isocyanate group (-N = C = O) in the activated PU . The Si-O-Ti bond recorded in the FTIR spectrum of TiO ₂ / PU indicates that the silanization process between TTIP and APTES to produce the titanosiloxane was successful. The FTIR spectrum of TiO ₂ / PU shows a strong increase in the NH and C = O absorption peaks, typical peaks of the urea group (-NH-CO-NH-), as compared to the activated PU. However, the isocyanate peak in TiO ₂ / PU was much reduced compared to the activated PU. Peak intensity changes indicate that a urea bond has been successfully formed based on the reaction between the isocyanate group of the activated PU and the amine group of the titanosiloxane. Therefore, based on the role of silicon bridge in APTES, titania was successfully coated on the surface of PU. Silicon can be connected to titania in TTIP via Si-O-Ti bonds. The amine groups in the APTES can react with isocyanate groups in the activated PU to form urea bonds.

The FTIR spectra of TiO ₂ / PU showed absorption peaks at 670 and 570 cm ^-1 , which were designated as the oscillation mode of the Ti-O-Ti bond. This peak appearance suggests that TiO ₂ was formed on the surface of PU based on the reaction between titanium alkoxide and H ₂ O.

< Experimental Example  2> XPS  analysis

Figure 2 is a high-Cu-TiO ₂ / of the PU in the Cu Cu 2p3 / 2 peak-represents the resolution XPS spectrum. A Gaussian multiple peak shape was applied to match the Cu 2p peak to determine the state of copper in Cu-TiO ₂ / PU. Peak analysis, there was a Cu ⁺ (932.3 eV) and Cu ^{2 +} (933.5 eV) the two components of the copper in the Cu-TiO ₂ / PU containing CuO in the in the Cu ₂ O. CuO in Cu-TiO ₂ / PU can be generated by photo-reduction, thermal decomposition of Cu (NO ₃ ) ₂ during UV irradiation or calcination, respectively. During the photo-deposition process, Cu ^{2 +} can be reduced to Cu ⁺ to form Cu ₂ O. Lin et al. Reported that Cu ^{2 +} cations penetrate the TiO ₂ lattice under UV irradiation, resulting in the formation of Cu-O-Ti bonds by substitution with Ti ^{4 +} cations [17]. Substitution can also lead to the formation of Cu ^{+ in} the TiO ₂ lattice. Therefore, the element states of the Cu dopant in Cu-TiO ₂ / PU included Cu ⁺ and Cu ^{2 +} . Most Cu ⁺ and Cu ^{2 +} exist in the form of Cu ₂ O and CuO, respectively, and they are physically adsorbed on the TiO ₂ surface. Another Cu ⁺ was present in the form of Cu-O-Ti bonds in the TiO ₂ lattice.

< Experimental Example  3> Morphology  And surface area analysis

The results of observation with a scanning electron microscope (SEM) to analyze the morphology of the pure PU, TiO ₂ / PU and the Cu-TiO ₂ / PU prepared in the example in the copper-titanium dioxide / polyurethane catalyst according to the present invention 3.

In FIG. 3, FIG. 3A is a SEM image of pure PU, FIG. 3B is a SEM image of TiO ₂ / PU, and FIG. 3C is a SEM photograph of Cu-TiO 2 / PU according to the present invention.

As shown in FIG. 3A, the pure PU contained pores having a size range of 100 to 300 μm. As shown in FIG. 3B, SEM photographs of PU coated with titanium dioxide showed that the pure PU had a SEM There was little difference in porosity when compared with photographs. Therefore, it was found that TiO ₂ was smooth and thinly coated on the PU surface in TiO ₂ / PU, and TiO ₂ layer did not significantly affect the pore size change of the PU substrate. Further, as shown in FIG. 3C, it was found that, in Cu-TiO ₂ / PU, small Cu ₂ O and CuO particles were well dispersed and deposited on the TiO ₂ layer.

Further, FIG. 3D shows a mixed mapping of Ti and Cu element in the Cu-TiO ₂ / PU materials made in accordance with the present invention. As shown in Figure 3D, the element mapping clearly indicated that the Ti and Cu elements were deposited almost evenly or alternately on the PU frame. Thus, the Cu-TiO ₂ / PU material according to the present invention can induce distinct photocatalytic activity for removal of bioaerosol since Ti and Cu elements are deposited evenly or alternately on the PU frame.

As a result of the surface area measurement, the BET surface area of synthesized TiO ₂ / PU was 111.4 m ² / g, which was much higher than that of PU (31.3 m ² / g) or TiO ₂ commercially available powder (60 m ² / g) . This high surface area suggests that TiO ₂ is immobilized on the surface of PU, thereby greatly improving the surface area of TiO ₂ . The BET surface area of Cu-TiO ₂ / PU synthesized according to one embodiment of the present invention was 166.3 m ² / g, which was higher than that of PU or TiO ₂ / PU. This may be due to the remarkable deposition of small Cu ₂ O and CuO particles on the TiO ₂ layer.

< Experimental Example  4> Light Absorption capacity  Measure

UV-Vis absorption spectra of PU, TiO ₂ / PU and Cu-TiO ₂ / PU are shown in FIG.

As shown in Fig. 4, when compared to TiO ₂ / PU and Cu-TiO ₂ / PU, PU did not exhibit any absorption capacity for light in the wavelength range of 300 to 700 nm, and the UV-Vis absorption of TiO ₂ / PU The spectrum showed an absorption edge at 390 nm and did not exhibit noticeable absorption in the visible light region, which is consistent with the light absorption properties of TiO ₂ [NR Khalid, E. Ahmed, Z. Hong, K. S, M. Ahmad, Y. Zhang, Ceramics International, 39 (2013) 7107-7113].

However, compared to the UV-Vis absorption spectrum of _{TiO 2 / PU, Cu-TiO} 2 / PU according to the invention exhibited a higher absorption capacity in not only exhibit a red shift of the absorption end of the visible light region. Red shift of the absorption edge for the Cu-TiO ₂ / PU materials is likely due to the role of the CuO absorption within said composite material. Pham and Lee report that a composite material comprising TiO ₂ and CuO can cause a reduction in the band gap energy of TiO ₂ resulting in a red shift of the absorption edge of the synthesized material, [TD Pham, BK Lee, Applied Surface Science, 296 (2014) 15-23]. Direct interface between the electron mobility of the CuO of the valence band and in conduction of electrons from the valence as TiO ₂ may also result in a red shift of the absorption edge for the Cu-TiO ₂ / PU materials. The high enhancement of the light absorption capacity of Cu-TiO ₂ / PU may be due to Cu doping, which can increase the light absorption capacity in the visible region. The enhanced visible light absorption of the observed Cu-TiO ₂ / PU is expected to significantly increase the photocatalytic activity of the synthesized material in the visible region.

Therefore, the Cu-TiO ₂ / PU according to the present invention uses a polyurethane containing pores having a honeycomb shape in a size range of 100 to 300 μm as a support, and the TiO ₂ layer coated on the polyurethane surface is a polyurethane It is possible to perform the function as an adsorbent by not only greatly influencing the pore size change of the adsorbent. Since small Cu ₂ O and CuO particles are well dispersed on the TiO ₂ layer and deposited, they exhibit high surface area and remarkably improve the light absorption ability in the visible light region, so that the adsorbent and the photocatalyst can be simultaneously performed. It can be usefully used to remove bioaerosol and volatile organic compounds (VOC).

The present invention has been described with reference to the preferred embodiments. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. Therefore, the disclosed embodiments should be considered in an illustrative rather than a restrictive sense. The scope of the present invention is defined by the appended claims rather than by the foregoing description, and all differences within the scope of equivalents thereof should be construed as being included in the present invention.

Claims (8)

A titanium dioxide thin film is fixed on a polyurethane support having a porous honeycomb structure, and the titanium dioxide thin film is fixed on a polyurethane support by C-Si-O-Ti bonds generated by using silicon as a bridge element, Multifunctional copper-titanium dioxide / polyurethane with both photocatalyst and adsorbent functions, doped with copper (Cu) on a titanium thin film. delete The method according to claim 1,
Characterized in that the copper (Cu) is doped onto the titanium dioxide thin film by photo-deposition, the multifunctional copper-titanium dioxide / polyurethane having both photocatalyst and adsorbent function. delete (a) introducing an isocyanate group (NCO) to the surface of the polyurethane to activate the polyurethane;
(b) silanizing the titanium;
(c) immersing an activated polyurethane containing an NCO group in a silanized titanium solution, followed by calcination to produce a titanium dioxide thin film fixed on the polyurethane; And
(d) doping copper (Cu) on the titanium dioxide thin film using photo-deposition to produce a multi-functional copper-carbon dioxide / polyurethane.
A method for producing a multifunctional copper-titanium dioxide / polyurethane having both the functions of the photocatalyst and the adsorbent of claim 1. 6. The method of claim 5,
In the step (a), the polyurethane is placed in a mixed solution of an organic solvent, toluene 2,4-diisocyanate (TDI) and anhydrous triethylamine and heated at 50 to 70 ° C for 1 to 2 hours &Lt; RTI ID = 0.0 &gt; polytetrafluoro-titanium &lt; / RTI &gt; 6. The method of claim 5,
The step (b) may be performed by reacting a solution of titanium tetraisopropoxide (TTIP) in an organic solvent with a solution of? -Aminopropyltriethoxysilane (APTES) in an organic solvent to silanate titanium to prepare a colloidal solution of titanosiloxane &Lt; / RTI &gt; titanium dioxide / polyurethane. 6. The method of claim 5,
Wherein the calcination of step (c) is carried out at 200-250 &lt; 0 &gt; C for 1-3 hours.

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