KR20150134582A - CHEMICAL DOPING OF SOL-GEL TiO2 FILM - Google Patents

Abstract

The present invention relates to a catalytic system, wherein catalyst nanoparticles are vacuum-metalized on an oxide thin film in which a base metal is doped, and a method for improving activity of a catalyst by metalizing the catalyst nanoparticles on the oxide thin film in which the base metal is doped. Specifically, the present invention relates to a catalytic system, wherein Pt nanoparticle is vacuum-metalized on a TiO_2 thin film, in which N or F is doped in a sol-gel method, in an arc plasma deposition method, and a method for improving the activity of the catalyst by metalizing the Pt nanoparticles on the TiO_2 thin film, wherein N or F is doped in the sol-gel method, in the arc plasma deposition method. The oxide thin film in which the base metal is doped, especially TiO_2 thin film, wherein N or F is doped, is used as a support. Therefore, the catalytic system has an excellent catalytic stability and has improved catalytic activity and a turnover frequency in comparison with a catalytic system using the oxide thin film in which the base metal is not doped as the support.

Description

CHEMICAL DOPING OF SOL-GEL TiO2 FILM < RTI ID = 0.0 >

The present invention relates to a catalyst system in which nanocatalyst particles are deposited on a non-metal doped oxide thin film, and a method of depositing nanocatalyst particles on a non-metal doped oxide thin film to increase the activity of the catalyst. More specifically, the sol-gel (sol-gel) method as N- and F- doped with TiO ₂ arc plasma vapor deposition method on the thin film (arc plasma deposition) by depositing a Pt nanoparticle catalyst system and sol-gel method to the N- and F- And a method of depositing Pt nanoparticles on the doped TiO ₂ thin film by arc plasma deposition to increase the activity of the catalyst.

The role of electronic excitation in the oxide-metal interface has attracted much attention in the field of interfacial chemistry and heterogeneous catalysis. The increase in catalytic activity due to the presence of an oxide-metal interface, also referred to as strong metal-support interaction (SMSI), is evidenced by Schwab ' s performance of a carbon monoxide oxidation reaction with an inverse Ag / It was first proposed by colleagues (GM Schwab, Angewandte Chemie-International Edition 6 (1967) 375). The above studies indicate that the activation energy varies as a function of semiconductor thickness, which means the importance of the metal-oxide interface area. In addition, the doping of metals and semiconductors has caused a change in the activation energy, which means that the Schottky barrier plays an important role. This effect has also been studied by Boffa and colleagues using rhodium deposited on a number of oxides (A. Boffa et al., J Catal 149 (1994) 149-158). They observed a remarkable effect in CO ₂ hydrogenation, in particular in the presence of the following three different oxides: a 14-fold increase in turnover: TiO _x , NbO _x , and TaO _x . When the metal-oxide interfacial area was maximized, the activity was maximal, which occurred when the oxide covered about a half of the monolayer. Interestingly, the increase in chemical reactivity was not significant for ZrO _x , VO _x , WO _x , and FeO _x . These studies suggest that the metal-oxide interface plays an important role in determining the chemical reactivity with many kinds of oxides (NiO, CeO 2, TiO _x , NbO _x , and TaO _x ). The oxides are semiconductors with bulk band gaps of 3-4 eV, which form a Schottky barrier between the metal and the oxide. Therefore, the catalyst activity can be changed by doping the substrate and adjusting the bandgap.

Titanium dioxide (TiO ₂ ) is a semiconductor material and catalytic support that is often studied and applied to a variety of applications including photocatalysis, photoelectrochemistry, and the like. Bandgap strains can be achieved using organic dyes as sensitizers, but stability is a problem. When used in aqueous solutions, the dye can be removed from the surface, raising questions about long-term stability. Alternatively, doping a transition metal in TiO ₂ or synthesizing a reduced TiO _x photocatalyst has been used to broaden the spectrum response. However, due to the increase of the thermal stability and the charge carrier recombination center, the titanium dioxide has been limited to being doped with the transition metal.

Asahi et al. Introduces a new attempt to broaden the photoreaction of TiO ₂ by doping nitrogen (R. Asahi et al., Science 293 (2001) 269-271). Kasahara et al. Reported the photoactivity of oxynitride (LaTiO ₂ N) having a band gap of 2.1 eV under light irradiation (A. Kasahara et al., The Journal of Physical Chemistry A 106 (2002) 6750-6753). Since then, many research groups have studied nonmetal doping of TiO ₂ photocatalysts. Many studies on doped TiO ₂ nanocrystals have been published and only a few studies have been published for thin films made by cost-effective techniques such as reactive sputtering (EY Seon-Hong Lee, Hideyuki Okumura and Keiichi N. Ishihara, Materials Transactions 50 (2009) 1805-1811). Over the past decade, there has been constant debate about using non-metal doped TiO ₂ to improve catalyst efficiency. Baker et al. Is the change in the carrier transport properties of TiO ₂ doped with fluorine and oxygen stoichiometry (stoichiometry) was observed (LR Baker, A. Hervier, H. Seo, G. Kennedy, K. Komvopoulos, GA Somorjai, The Journal of Physical Chemistry C 115 (2011) 16006-16011). They emphasize that the increase in catalytic activity for CO oxidation leads to an active reaction with CO by activating the surface oxygen. The activation process was a major result of F doping, which facilitated the transfer of electrons from TiO ₂ to surface adsorbates.

In the present invention, the present inventors borrowed a two-dimensional model catalyst system made of Pt nanoparticles on a chemically modified TiO ₂ thin film prepared by arc plasma deposition (APD). The present inventors have found that TiO ₂ thin films prepared using the sol-gel method and chemically modified with nitrogen and fluorine are excellent in stability under most circumstances. The present inventors prepared a Pt-doped TiO ₂ system, and then performed a catalytic reaction for the CO oxidation reaction. During the catalytic reaction of the charge transport between the Pt nanoparticles and the support, the potential cause of increased catalytic activity will be discussed.

It is an object of the present invention to provide a catalyst system in which nanocatalyst particles are deposited on a nonmetallically doped oxide thin film and to provide a method of depositing nanocatalyst particles on the nonmetallically doped oxide thin film to increase the activity of the catalyst will be.

More specifically, it is an object of the present invention to provide a catalyst system in which Pt nanoparticles are deposited on a thin film of TiO ₂ doped N- and F-doped by a sol-gel method, - and F-doped TiO ₂ thin films by depositing Pt nanoparticles on the TiO ₂ thin film.

In order to achieve the above object, the present invention provides a catalyst system in which nanocatalyst particles are deposited on a non-metal-doped oxide thin film.

The present invention provides a method for increasing the activity of a catalyst by depositing nanocatalyst particles on a non-metal doped oxide thin film.

In one embodiment of the present invention, the non-metal doping may be nitrogen-doped or fluorine-doped.

In one embodiment of the present invention, the oxide thin film may be a thin film of CeO ₂ , Nb ₂ O ₅ , TaO ₅ , SiO ₂ or TiO ₂ .

In one embodiment of the present invention, the nanocatalyst particles may be selected from the group consisting of Au, Ag, Pt, Co, Ni, Pd, have.

In one embodiment of the present invention, the oxide thin film may be manufactured by a sol-gel method.

In one embodiment of the present invention, the nanocatalyst particles may be deposited on the oxide thin film by arc plasma deposition.

In one embodiment of the present invention, the oxide thin film may be annealed at a temperature of 250 to 550 ° C.

In one embodiment of the present invention, the nitrogen-doping can be doped with a molar concentration of nitrogen of 1M to 10M.

In one embodiment of the present invention, the fluorine-doping may be doped with a percent concentration of fluorine ranging from 5% to 20%.

In one embodiment of the present invention, the catalyst may be used for CO oxidation.

The present invention provides a catalyst system in which nanocatalyst particles are deposited on a non-metal doped oxide thin film and a method of depositing nanocatalyst particles on a non-metal doped oxide thin film to increase the activity of the catalyst. More specifically, the sol-gel method as N--gel (sol-gel) method as N- and F- doped with TiO ₂ thin film in the arc plasma vapor deposition method (plasma arc deposition) in the catalyst system, and the sole by depositing the Pt nanoparticles And depositing Pt nanoparticles on the F-doped TiO ₂ thin film by arc plasma deposition to increase the activity of the catalyst.

The present invention relates to the use of a non-metal-doped oxide thin film, particularly an N- or F-doped TiO ₂ thin film, as a support in the catalyst system, as compared to a catalyst system using a non-metal undoped oxide thin film as a support, Has catalytic activity and a turnover frequency, and exhibits excellent catalyst stability.

Figure 1 shows an SEM image of N-doped TiO ₂ at various molar concentrations of nitrogen: (a) 1M, (b) 3M. (c) 5M, and (d) 10M.
Figure 2 shows the XRD pattern of doped and undoped TiO ₂ after annealing at a temperature of 250-550 ° C with anatase peak highlighted: (a) 3M N-doped TiO ₂ , (b) 10% F-doped TiO ₂ , (c) undoped TiO ₂ , where R corresponds to a rutile peak,
Figure 3 shows UV-Vis absorption spectroscopy of (a) TiO ₂ N-doped at different molar concentrations of nitrogen and (b) F-doped TiO ₂ at various percentages of fluorine.
Figure 4 shows a SEM image of APD Pt nanoparticles on (a) F-doped TiO ₂ , (b) N-doped TiO ₂ , and (c) undoped TiO ₂ . (d) TEM image of APD Pt nanoparticles deposited on a SiO ₂ TEM grid using 10 pulse shots under an arc discharge voltage of 100 V. FIG.
Figure 5 shows (a) XPS analysis of APD Pt nanoparticles on undoped, N- and F-doped TiO ₂ ; (b) a peak of N1s 3M N- doped TiO ₂ is inserted key (interstitial) and represents a substituted characteristic peaks; (c) the F1s peak of 10% F-doped TiO _{2 represents} the peak of the major displacement characteristic; And (d) the oxidation state of the Pt nanoparticles with respect to the support.
Figure 6 shows the catalytic activity for CO oxidation reactions: (a) turnover frequency and (b) Arrhenius diagram shows 24.8 kcal / mol (Pt on F-doped TiO ₂ ), 28.2 kcal / mol (Pt on N-doped TiO ₂ ), and 24.4 kcal / mol (Pt on undoped TiO ₂ ). (c) a schematic diagram of the electron excitation mechanism of the surface oxygen by charge transport from the conduction band gap of TiO ₂ to the absorbed O. FIG.

The present inventors have studied the effect of a support on catalytic activity for CO oxidation using platinum nanoparticles on doped and undoped titanium dioxide (TiO ₂ ). Undoped TiO ₂ as a support was synthesized via a sol-gel process. The thin film was then chemically doped with non-metallic anions such as nitrogen (N) and fluorine (F). Thin films are prepared using a sputter coating technique; X-ray diffraction (XRD), UV-Vis absorption spectroscopy, and X-ray photoelectron spectroscopy (XPS) were performed using a scanning electron microscope (SEM) Were performed to investigate the morphology, crystal phase, crystallites, optical properties and elemental composition of the films, respectively. In particular, the XPS analysis of the doped TiO ₂ thin films showed that the nitrogen sites are implanted, while the fluorine is doped in the TiO ₂ lattice in a substituted form. The Pt / N-, Pt / F-, and Pt / undoped TiO ₂ catalysts were deposited on N-, F-, and undoped TiO ₂ thin films using arc plasma deposition (APD) ≪ / RTI > nanoparticles. To explain the catalytic activity of Pt nanoparticles, a CO oxidation reaction was performed. The turnover rate of Pt / N-doped TiO ₂ and Pt / F-doped TiO ₂ was 2.5 times higher than that of Pt / undoped TiO ₂ . The catalytic activity is believed to be increased by electron excitation and oxygen vacancy formed during the doping process.

In the present invention, "sol-gel method" is a method for producing an oxide solid by modifying a sol into a gel by proceeding a hydrolysis and condensation reaction of a compound in a solution of a metal in a solution and heating the gel First, the metal nanoparticles are present in a liquid state as sol-like metal particle suspensions and then dissolved in the form of alkoxide, which reacts with water or an alcohol in the form of metal hydroxide . These metal hydroxides form a solid network through a covalent bond to each other and form a gel. This process is called the sol-gel method.

The sol-gel method is capable of synthesizing metal oxides even at room temperature and has the advantage of controlling the original physico-chemical properties from the molecular stage by controlling the manufacturing parameters using chemical phenomena at each step. That is, the sol-gel method can increase the uniformity of the prepared particles by mixing the raw materials at the molecular level, can produce particles with high surface area, and can lower the sintering temperature, It has been widely used. In particular, the sol-gel method using alkoxide of high purity has a wide application range and has the advantage that the final product form can be adjusted to powder, monolith and fiber form.

Conventionally, an oxide thin film is formed on a substrate by a process such as physical vapor deposition (PVD) or chemical vapor deposition (CVD). A major disadvantage of the deposition of the oxide through this method is that it requires a high vacuum or high temperature. However, in the present invention, by using the sol-gel method, it is possible to deposit an oxide thin film on a substrate through the simplest chemical reaction and to manufacture a high-purity oxide thin film having a uniform chemical composition even at a low temperature .

The oxide thin film of the present invention is selected from the group consisting of CeO ₂ , Nb ₂ O ₅ , TaO ₅ , SiO ₂ and TiO ₂ , preferably CeO ₂ , Nb ₂ O ₅ , SiO ₂ or TiO ₂ , more preferably from CeO _2, Nb ₂ O _5, or TiO _2.

The nanocatalyst particles of the present invention may be at least one selected from the group consisting of gold (Au), silver (Ag), platinum (Pt), cobalt (Co), nickel (Ni), palladium (Pd) and iridium But is not limited thereto, and is preferably gold (Au), silver (Ag) or platinum (Pt), more preferably platinum (Pt).

The nanocatalyst of the present invention is preferably synthesized by APD. APD enables large-scale synthesis of nanocatalysts and allows study of intrinsic factors affecting catalytic activity.

The nanocatalyst of the present invention is preferably particles having a size of 1 to 20 nm. When the size of the metal particles is less than 1 nm, there is a problem that the metal particle layer is not formed well. When the size of the metal particles exceeds 20 nm, there is a problem that the surface area of the metal particles is decreased and the catalytic activity is lowered. The nanocatalyst of the present invention is more preferably 2 to 10 nm, even more preferably 2.5 to 5 nm.

Example

Hereinafter, the present invention will be described in more detail with reference to Examples. It is to be understood by those skilled in the art that these examples are for illustrative purposes only and that the scope of the present invention is not construed as being limited by these examples.

≪ Example 1 > ₂  Formation of sol

(1) undoped TiO ₂  Formation of brush

Undoped titanium dioxide was prepared by methods well known in the art of the present invention. Titanium tetrabutyloxide (TTBO) as a Ti precursor, diethanolamine (DEA) as a stabilizer and ethyl alcohol (EtOH) as a solvent were used. All reagents were assay grade and used without further purification. The chemical molar composition of the starting solution was TTBO: H ₂ O: DEA: EtOH = 1: 26.5: 1: 1. The solution was stirred continuously for 2 hours, resulting in the formation of a clear TiO ₂ sol. Then, in order to complete the reaction, the brush was aged for 24 hours.

(2) fluorine-doped TiO ₂  (F-TiO ₂ ) Formation of brush

A fluorine-doped titanium dioxide (F-TiO ₂ ) sol was synthesized according to a procedure similar to that described above, wherein ammonium fluoride (NH ₄ F) was used as the fluorine precursor. To synthesize 5%, 10%, 15% and 20% F-TiO ₂ sols, the molar ratio of NH ₄ F to TTBO was used as 0.05, 0.1, 0.15 and 0.2. The percent concentration (%) means the ratio of the molar mass of the fluorine precursor to the molar mass of the TiO ₂ precursor (molar mass of fluorine precursor used / molar mass of the TiO ₂ precursor used x 100). That is, F-TiO percent concentration of the _second brush in the present embodiment, refers to the ratio of the molar mass of NH ₄ F for the molar mass of TTBO (a NH ₄ F molar mass / a TTBO molar mass x 100 Using ). The sol was stirred for 2 hours and aged for 24 hours to prepare a thin film.

(3) Nitrogen-doped TiO ₂  (N-TiO ₂ ) Formation of brush

A nitrogen-doped titanium dioxide (N-TiO ₂ ) thin film was prepared using urea as a dopant precursor. Among the typical experimental methods, Pillai et al. 10 ml of titanium isopropoxide (TIP) was used as the metal precursor and added to acetic acid (20 ml) and stirred (MB Fisher, DA Keane, P. Fernandez- Ibanez, J. Colreavy, SJ Hinder, KG McGuigan, SC Pillai, Applied Catalysis B: Environmental 130-131 (2013) 8-13). To hydrolyze the mixture, deionized water (60 ml) was added dropwise to the mixture with vigorous stirring. TIP, acetic acid and water were added in a molar ratio of 1: 10: 100. The solution is stirred for 2 hours, the transparent TiO ₂ sol (sol) was obtained. To produce N-TiO ₂ , the urea (1.77 g) mixed in EtOH (15 ml) was added to the prepared TIP-acetic acid mixture to give a molar concentration of various nitrogens to the mixed solution of TIP, acetic acid, water and EtOH the colorless N-TiO ₂ sol having a form. Typical aqueous urea solutions produce highly heterogeneous films and can not be used directly for doping. In this case, EtOH is used as the solvent during the preparation of the brush.

≪ Example 2 > ₂  Sol, F-TiO ₂  Sol and N-TiO ₂  Formation of Sol-Spin Coated Thin Films

Thin films were prepared by spin coating at 3000 rpm for 20 seconds. Silica wafers, which were cleaned ultrasonically with ethanol and water for 10 minutes, and dried under nitrogen, were used as substrates. In order to obtain an anatase phase known as an efficient phase exhibiting the highest catalytic activity, the prepared thin film was annealed at 350 ° C for 2 hours. The morphology of the various molar concentrations of N-TiO ₂ thin films is shown in FIG.

≪ Example 3 > ₂  Deposition of Pt nanoparticles on a thin film

In order to deposit Pt nanoparticles in the prepared thin film, we used a coaxial pulsed arc plasma deposition (APD) system (ULVAC, ARL-300). The system parameters for depositing Pt nanoparticles (~ 2.7 nm) in the thin film are similar to those well known in the art. Briefly, the deposition was performed at room temperature under a vacuum of 10 ^-6 torr. The cathode electrode was coaxially fixed to a platinum anode rod separated by an insulator. A trigger electrode induces an arc discharge on the anode rod to produce a highly ionized platinum plasma. By varying the voltage applied to the trigger electrode, the average size of the nanoparticles deposited on the target surface is regulated later. Each pulse is deposited from about ^{8 x 10 -4 mg / cm 2} . In this experiment, 10 pulses of Pt were deposited on the F-TiO ₂ , N-TiO _2, and undoped titanium dioxide thin films, respectively. The present inventors measured the catalytic activity in a CO oxidation reaction using an ultrahigh vacuum batch reactor (10 ^-8 torr pressure). The reaction chamber was charged at room temperature with 40 torr CO, 100 torr O _2, and 620 torr He; The reaction mixture was continuously circulated at 2 L / min using a recirculation pump. CO conversion was monitored and the reaction mixture was analyzed on-line by gas chromatograph (GC) at a temperature of 220-260 < 0 > C.

In the present invention, doped titanium dioxide was synthesized by the sol-gel method by hydrolysis of an N-substituted titanium isopropoxide and an F-substituted titanium tetrabutoxide precursor in an alcohol solution. Different molar concentrations of nitrogen precursors were used to synthesize N-TiO ₂ at various doping levels. As shown by the SEM image of the N-TiO ₂ thin films with various nitrogen molar concentrations (FIG. 1), as the doping level of nitrogen increased from 1 M to 3 M, ease of formation and film quality improved; The size of the crystals increased with increasing annealing temperature, but was well maintained and continuous. As the doping level was further increased (i. E., 5 M and 10 M nitrogen concentration), a completely discontinuous, irregular thin film of flake-like structure was formed.

As shown in FIG. 2, the undoped, N and F-doped TiO ₂ crystal phases were analyzed using X-ray powder diffraction (XRD). Both N- and F-doped samples were annealed in a muffle furnace at a temperature ranging from 250 to 550 占 폚 for 2 hours at a temperature increase of 10 占 폚 / min. After the annealing process, the samples were cooled to room temperature. Anatase peaks that exhibit sharp peaks at 2? = 25.3 ° and an effective surface catalytic crystal phase appear after annealing the thin film at 350 ° C or higher; When the temperature is lower than 350 DEG C, the thin film has an amorphous phase which does not have a peak. In the case of F-TiO ₂ , the anatase peak appears after annealing the sample at 450 ° C or higher, which is a general characteristic of fluorine-doped TiO ₂ .

The optical properties of the samples were evaluated by characterizing the samples with ultraviolet-visible absorption spectroscopy (UV-Vis absorption spectroscopy). Figure 3 is, as compared with the non-doped TiO ₂ shows the UV-Vis spectra of the N- and F-TiO _2. Yang et al. Did not observe any significant shift of the absorption peak of F-doped TiO ₂ , which means that F-doping has no effect on red shift (H. Yang, X. Zhang, Journal of Materials Chemistry 19 (2009) 6907-6914). These results show that the doped F atoms do not have a significant effect on the band gap of TiO ₂ . In the report by, and F- in the doped TiO ₂ and the discrepancy calculation results (Fisher MB, DA Keane, P. Fernandez-Ibanez, J. Colreavy, SJ Hinder, KG McGuigan, SC Pillai, Applied Catalysis B: Environmental 130 -131 (2013) 8-13). Figure 3 (a) shows the increased optical properties of nitrogen-doped titanium dioxide, including the effect of doping on changes in optical properties related to the degree of nitrogen doping. The increased optical properties due to doping implies a reduction in the bandgap of titanium dioxide for various potential applications. In Fig. 3 (b), a slight shift to the visible spectrum is explained by the formation of an oxygen vacancy space by the fluorine precursor. Figure 4 shows TEM images of APD Pt nanoparticles deposited on a SiO ₂ TEM grid using a SEM image of Pt nanoparticles on F-, N-, and undoped TiO ₂ and 10 pulse shots under an arc discharge voltage of 100 V Image.

The chemical composition was confirmed by XPS analysis. Figure 5 shows XPS data for APD Pt nanoparticles on undoped, N- and F-doped TiO ₂ ; N1s peak of 3M N- doped TiO ₂ is inserted key (interstitial) and represents a substituted characteristic peaks; The F1s peak of 10% F-TiO ₂ shows the peak of the major displacement characteristic; And the oxidation state of the Pt nanoparticles with respect to the support. During the fitting of the data, the reference carbon C1s peak was observed at 284.6 eV. In Figure 5 (b), we were able to observe a binding energy peak of 399.16 eV, which is an implanted doping of the nitrogen to the TiO ₂ lattice, a small shoulder at 397.09 eV, . These values are also consistent with F. Peng et al. Reported that the N1s peak at 396 - 397.5 eV is for nitrogen atoms, which are substituted for the TiO ₂ lattice as a Ti-N-Ti bond (F. Peng, L. Cai, H. et al. Yu, H. Wang, J. Yang, Journal of Solid State Chemistry 181 (2008) 130-136). 5 (c) shows the binding energy peak of F-doped TiO ₂ . The present inventors were able to observe one major peak at 683.5 eV. Since F and O have similar atomic diameters, this peak relates to doped F atoms in TiO ₂ ; F atoms replaced oxygen atoms in the lattice and then formed Ti-F bonds. A support for the doped TiO ₂ oxidation state of the Pt nanoparticles, - the support than to the non-doped TiO ₂ 40% lower (Figure 5 (a), (d) ). 6 (a) and 6 (b) show Arrhenius diagrams showing the results of the CO oxidation reaction and the activation energies of the samples, respectively, regarding the turnover frequency (TOF). The turnover rate of CO oxidation in APD Pt / N-doped TiO ₂ and APD Pt / F-doped TiO ₂ means 2.5 times higher catalytic activity than APD Pt / undoped TiO ₂ ; The activation energy of Pt on N-doped TiO ₂ (28.2 kcal / mol) is higher than that of Pt / undoped TiO ₂ (24.4 kcal / mol) and Pt / F-doped TiO ₂ (24.48 kcal / mol).

A possible mechanism for the increase in catalytic reaction can be explained by the increased concentration of oxygen vacancy in the case of N-TiO ₂ . On the other hand, in the case of F-TiO ₂ , electron excitation is possible by electron excess to oxygen absorbed from TiO ₂ to form an activated O-intermediate which immediately reacts with CO. Figure 6 (c) shows an energy plot for the electron excitation mechanism of surface oxygen by charge transport from the conduction band of TiO ₂ to O ₂ absorbed. Alternatively, the low oxidation state of Pt / doped TiO ₂ (Fig. 5 (d)) caused by increased charge transport shows high catalytic activity in the CO oxidation reaction. Thus, this study describes the role of the dopant of the support in the catalytic activity of the metal / oxide catalyst, and to investigate the metal-support interaction by changing the doping of the oxide support to improve catalytic activity, A new approach to the catalyst system is proposed.

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 (21)

A method for depositing nanocatalyst particles on a non-metal doped oxide thin film to increase the activity of the catalyst. The method according to claim 1,
Wherein the non-metal doping is nitrogen-doped or fluorine-doped. The method according to claim 1,
The oxide thin film is _{CeO 2, Nb 2 O 5,} TaO 5, SiO 2 or characterized in that the TiO ₂ thin film. The method of claim 3,
Wherein the oxide thin film is a TiO ₂ thin film. The method according to claim 1,
Wherein the nanocatalyst particles are gold (Au), silver (Ag), platinum (Pt), cobalt (Co), nickel (Ni), palladium (Pd), or iridium (Ir). 6. The method of claim 5,
Wherein the nanocatalyst particles are platinum (Pt). The method according to claim 1,
Wherein the oxide thin film is manufactured by a sol-gel method. The method according to claim 1,
Wherein the nanocatalyst particles are deposited on the oxide thin film by arc plasma deposition. The method according to claim 1,
Wherein the oxide thin film is annealed at a temperature of 250 to 550 占 폚. 3. The method of claim 2,
Characterized in that the nitrogen-doping is carried out with a molar concentration of nitrogen from 1 M to 10 M. 3. The method of claim 2,
The fluorine-doping, is carried out as a percentage of the concentration of 5% to 20% fluorine, characterized in that the ratio of the molar mass of the fluorine precursor used for the molar mass of the percent concentration of the TiO ₂ precursor used. The method according to claim 1,
Wherein the catalyst is used in a CO oxidation reaction. A catalyst system in which nanocatalyst particles are deposited on a non-metal doped oxide thin film. 14. The method of claim 13,
Wherein the non-metal doping is nitrogen-doped or fluorine-doped. 14. The method of claim 13,
Wherein the oxide thin film is a TiO ₂ thin film. 14. The method of claim 13,
Wherein the nanocatalyst particles are platinum (Pt). 14. The method of claim 13,
Wherein the oxide thin film is manufactured by a sol-gel method. 14. The method of claim 13,
Wherein the nanocatalyst particles are deposited on the oxide thin film by arc plasma deposition. 14. The method of claim 13,
Characterized in that the nitrogen-doping is carried out with a molar concentration of nitrogen from 1 M to 10 M. 14. The method of claim 13,
The fluorine-doping, 5% to be performed as a percent concentration of 20% fluorine, the percent concentration of the catalyst system, characterized in that the ratio of the molar mass of the fluorine precursor used for the molar mass of the TiO ₂ precursor used. 14. The method of claim 13,
Wherein the catalyst system is used in a CO oxidation reaction.

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