KR101868904B1 - MESOPOROUS IRON OXIDE COMPLEX COMPRISING Pt ATOM AND METHOD FOR PREPARING THE SAME - Google Patents

Abstract

The present invention relates a carrier containing mesoporous iron oxide, and a mesoporous iron oxide complex containing a platinum nanoparticle or a platinum single atom supported on the carrier. By supporting platinum on a surface of the carrier containing mesoporous iron oxide, it is possible to improve efficiency in catalytic reactions while having high activities and high selectivity.

Description

TECHNICAL FIELD [0001] The present invention relates to a mesoporous iron oxide composite containing platinum and a method for producing the same,

The present invention relates to a mesoporous iron oxide composite and a method for producing the same, and more particularly, to a mesoporous iron oxide composite containing platinum single atom or platinum nanoparticles supported on a support containing mesoporous iron oxide.

It is useful in various industries to carry a catalytic reaction having a high activity and a high selectivity by carrying a noble metal catalyst such as gold (Au), palladium (Pd), ruthenium (Ru), and platinum (Pt) It is a way of doing. Since noble metal catalysts are very expensive, research on obtaining the desired catalytic activity while minimizing the amount of this noble metal catalyst is very important. As a method of minimizing the amount of the noble metal catalyst, there is a method of increasing the catalytic activity by enlarging the surface area of the catalyst which can cause the catalytic reaction by minimizing the size of the noble metal catalyst. As the size of the catalyst is reduced, not only the surface area is widened but also the nanomaterial can be used as a good catalytic reaction site because the surface state of the nanomaterial is lowered unlike the bulk material. Therefore, studies for reducing the size of noble metal catalysts are very important for the efficient use of catalysts, and research on controlling synthesis and shape of noble metal nanoparticles has been conducted recently.

However, nanometer-scale nanoparticles do not appear on the surface, and there are many noble metal atoms that are not used in the reaction. Therefore, to increase the catalytic activity per atom of noble metal, it would be the most ideal way to reduce the size of nanoparticles and to use noble metal catalyst in single atom state. If the size of the particles is reduced to a single atomic state, a lower coordination state, a quantum size effect, and a greater interaction between the metal and the support can result in greater catalytic activity. However, since single atoms have very large surface energies, they are easily clustered at room temperature.

To overcome this, several researchers have developed a method to support single atom catalysts in appropriate support. Adv. Mater. (FeO _x / Pt ₁ ) on the iron oxide (FeO _x ) of the non-porous nanoparticles was studied in Nature Chemistry 3, 634-641 (2011), 2014, 26, 8147-8153. FeO _x / Pt ₁ showed high catalytic activity in oxidizing carbon monoxide to carbon dioxide.

However, this conventional method is iron oxide (FeO _x) is non-porous and, iron oxide (FeO _x) and platinum single atom is reacted at the same time FeO _x / Pt ₁ because synthesis of a platinum single-valence iron oxide (FeO _x ) As well as on the surface of the catalyst, and platinum single atoms are clustered together, resulting in low catalytic activity.

DISCLOSURE OF THE INVENTION In order to solve the above problems, it is an object of the present invention to provide a method for producing a mesoporous carbonaceous material, which is capable of supporting platinum on the outer surface of a carrier including mesoporous iron oxide, Iron oxide composite.

According to an aspect of the present invention, there is provided a method of manufacturing a honeycomb structured body, comprising: a carrier including mesoporous iron oxide having mesopores; And a catalyst supported on an outer surface of the mesoporous iron oxide and a catalyst supported on a surface in contact with the mesopores therein.

The catalyst may comprise a platinum single atom.

The catalyst may comprise platinum nanoparticles.

The mesoporous iron oxide may have a three-dimensional skeleton and the mesopores formed by the three-dimensional skeleton.

The size of the mesopores may be between 2 and 50 nm, preferably between 2 and 20 nm.

The iron oxide may be at least one member selected from the group consisting of FeO, Fe ₃ O ₄ and Fe ₂ O ₃ , preferably Fe ₂ O ₃ .

The weight percentage of platinum carried on the mesoporous iron oxide composite may be 0.01 to 10 wt%.

According to another aspect of the present invention, there is provided a process for preparing a mesoporous iron oxide, comprising: (a) preparing a carrier comprising mesoporous iron oxide having mesopores; (b) preparing a mixture comprising said support, a platinum precursor and a solvent; And (c) stirring the mixture, subjecting the mixture to a reduction reaction, and drying the mixture to produce the mesoporous iron oxide composite of (2).

(C-1) heat-treating the reduction reaction of step (c); And (c-2) heat treating under 10% H ₂ / Ar gas.

The heat treatment may be performed at a temperature of 100 ° C to 500 ° C.

According to another aspect of the present invention, there is provided a process for preparing a mesoporous iron oxide, comprising: (a) preparing a carrier comprising mesoporous iron oxide having mesopores; (a ') preparing a platinum precursor mixed solution including a platinum precursor, ethylene glycol, and sodium hydroxide; (b) preparing a mixture comprising the support, the platinum precursor mixture solution and a solvent; And (c) stirring and drying the mixture to produce the mesoporous iron oxide composite of claim 3. The present invention also provides a method for producing a mesoporous iron oxide composite.

Wherein step (a) comprises: (a-1) preparing mesoporous silica (KIT-6); (a-2) preparing a mixture comprising the mesoporous silica (KIT-6), an iron precursor, and a solvent; (a-3) heat-treating the mixture to prepare a composite comprising iron oxide and KIT-6; (a-4) removing the KIT-6 from the complex to prepare a carrier including mesoporous iron oxide.

In step (a-2), the iron precursor comprises at least one selected from iron nitrate nonahydrate, iron chloride hexahydrate, and iron chloride tetrahydrate .

In step (a-4), the KIT-6 can be removed by sodium hydroxide (NaOH).

The platinum precursor may include at least one selected from the group consisting of chloroplatinic acid hydrate, sodium hexachloroplatinate hexahydrate and potassium hexachloroplatinate.

The solvent may be a polar solvent.

The mesoporous iron oxide composite according to the present invention has an effect of enhancing the catalytic reaction efficiency by supporting platinum on the surface of the carrier containing mesoporous iron oxide.

1 is a schematic diagram of a method for synthesizing a platinum single atom-introduced mesoporous iron oxide complex (m-FeO _x / Pt ₁ ) according to Example 1.
2 is an XRD pattern of a mesoporous iron oxide composite (m-FeO _x ) prepared according to Example 1. Fig.
3 is a TEM image of a platinum single atom-introduced mesoporous iron oxide complex (m-FeO _x / Pt ₁ ) prepared according to Example 1. Fig.
4 (a) is a BET isotherm (Brunauer-Emmett-Teller adsorption isotherm) graph using a nitrogen adsorption method of a carrier (m-Fe ₂ O ₃ ) containing mesoporous iron oxide produced according to Production Example 2, and b) is a graph showing the pore size of the carrier (m-Fe ₂ O ₃ ) containing mesoporous iron oxide prepared according to Production Example 2. FIG.
5 is a graph showing Fourier-transform infrared spectroscopy (FT-IR) of a mesoporous iron oxide composite (m-FeO _x / Pt ₁ ) having platinum single atoms introduced according to Example 1 with CO gas introduced therein.
6 (a), 6 (b) and 6 (c) are cross-sectional views of a mesoporous iron oxide composite (m-FeO _x / Pt ₁ -2 wt%) containing a platinum single atom- (D), (e) and (f) are images of a high-angle annular dark field-scanning transmission electron microscope (HAADF-STEM) The mesoporous iron oxide complex (m-FeO _x / Pt NPs-2 wt%) HAADF-STEM image.
7 (a) is an absorption spectrum of a platinum single atom-introduced mesoporous iron oxide composite (m-FeO _x / Pt ₁ ) prepared according to Example 1, and (b) The mesoporous iron oxide complex (m-FeO _x / Pt NPs). 7 (c) is a graph showing Ab _Pt1 / Ab _NPs according to weight percent of platinum.
FIG. 8 is a graph showing the results of measurement of the permeability of a mesoporous iron oxide composite (m-FeO _x / Pt ₁ -1 wt%) containing 1 wt% of platinum prepared according to Example 1-4 and 1 wt% of platinum prepared according to Comparative Example 1-1 is an absorption spectrum of a non-porous iron oxide complex (FeO _x / Pt ₁ -1 wt%).

The invention is capable of various modifications and may have various embodiments, and particular embodiments are exemplified and will be described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

Furthermore, terms including an ordinal number such as the first, second, etc. to be used below can be used to describe various elements, but the constituent elements are not limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

Also, when an element is referred to as being "formed" or "laminated" on another element, it may be directly attached or laminated to the front surface or one surface of the other element, It will be appreciated that other components may be present in the < / RTI >

The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

The present invention relates to a carrier comprising mesoporous iron oxide having mesopores; And a catalyst supported on the outer surface of the mesoporous iron oxide and a catalyst supported on a surface in contact with the mesopores in the mesoporous iron oxide composite.

The catalyst may comprise platinum single atoms and may comprise platinum nanoparticles.

The platinum single atom is located in the lattice at the position where iron is displaced from the iron oxide.

The mesoporous iron oxide may have a three-dimensional skeleton and the mesopores formed by the three-dimensional skeleton.

The size of the mesopores may be between 2 and 50 nm, preferably between 2 and 20 nm. If the size of the mesopores is less than 2 nm, the mass transfer is not easy because the mass transfer is not easy. If the mesopore size is more than 50 nm, the surface reaction area is reduced.

The iron oxide may be at least one member selected from the group consisting of FeO, Fe ₃ O ₄ and Fe ₂ O ₃ , preferably Fe ₂ O ₃ .

The weight percentage of platinum carried on the mesoporous iron oxide composite may be 0.01 to 10 wt%, preferably 0.01 to 8 wt%. If the weight percentage of the supported platinum is less than 0.01 wt%, the density of the platinum present on the surface is too low to perform the reaction well, and if it exceeds 10 wt%, the amount of platinum is large,

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram of a method for synthesizing a platinum single atom-introduced mesoporous iron oxide composite of the present invention. FIG.

Hereinafter, a method for producing a platinum single atom-bearing mesoporous iron oxide composite of the present invention will be described with reference to FIG.

First, a support containing mesoporous iron oxide having mesopores is prepared (step a).

Next, a mixture comprising the support, the platinum precursor and the solvent is prepared (step b).

Next, the mixture is stirred, reduced, and dried to produce a mesoporous iron oxide complex containing platinum single atoms (step c).

In step (c), the reduction reaction may be carried out in the following two steps.

First, heat treatment is performed (step c-1).

Next, heat treatment is performed under 10% H ₂ / Ar gas (step c-2).

The heat treatment may be performed in the range of 100 ° C to 500 ° C, preferably 200 ° C to 400 ° C. If the heat treatment temperature is less than 100 ° C, a part of the platinum precursor may not be reduced to a single platinum atom, which is undesirable. If the temperature exceeds 500 ° C, platinum single atoms may clump together.

Hereinafter, a method for producing the mesoporous iron oxide composite on which platinum nanoparticles of the present invention are supported will be described.

First, a support containing mesoporous iron oxide having mesopores is prepared (step a).

Next, a platinum precursor mixed solution containing a platinum precursor, ethylene glycol and sodium hydroxide is prepared (step a ').

Next, a mixture containing the carrier, the platinum precursor mixture solution and the solvent is prepared (step b).

Next, the mixture is stirred and dried to prepare a mesoporous iron oxide complex containing platinum nanoparticles (step c).

Specifically, step (a) can be performed in four steps.

First, mesoporous silica (KIT-6) is prepared (step a-1).

The mesoporous silica may be used as a template.

The mesoporous silica (KIT-6) may be prepared by mixing a silica precursor and a solvent, and the silica precursor may be selected from the group consisting of tetraethyl orthosilicate, tetramethyl orthosilicate, sodium silicate silicate), and the like, and preferably tetraethyl orthosilicate can be used.

Next, a mixture comprising the mesoporous silica (KIT-6), the iron precursor and the solvent is prepared (step a-2).

The iron precursor may be iron nitrate nonahydrate, iron chloride hexahydrate and iron chloride tetrahydrate. Preferably, iron precursor is iron nitrate nonahydrate, iron chloride hexahydrate, iron chloride tetrahydrate, nitrate nonahydrate) can be used.

Next, the mixture is heat-treated to prepare a composite containing iron oxide (Fe ₂ O ₃ ) and KIT-6 (step a-3).

Next, the KIT-6 is removed from the complex to prepare a carrier containing mesoporous iron oxide (step a-4).

The KIT-6 can be removed by sodium hydroxide (NaOH), and the removal can be carried out twice.

The platinum precursor may be chloroplatinic acid hydrate, sodium hexachloroplatinate hexahydrate and potassium hexachloroplatinate, preferably chloroplatinic acid hydrate, sodium hexachloroplatinate hexahydrate and potassium hexachloroplatinate, It may be a chloroplatinic acid hydrate.

The solvent may be a polar solvent, preferably ethanol.

Hereinafter, the present invention will be described in more detail by way of examples. However, this is for illustrative purposes only, and thus the scope of the present invention is not limited thereto.

[Example]

Preparation Example 1: Preparation of mesoporous silica (KIT-6)

144 g of distilled water and 7.9 g of 35 wt% HCl were mixed, and 4 g of Pluronic P 123 was added and dissolved at 35 캜 to prepare a mixed solution. To the mixed solution, 4 g of butanol was added. After one hour, 8.6 g of tetraethyl orthosilicate was added and reacted at 35 ° C for 24 hours to prepare a mixture. The mixture was reacted in an oven at 100 ° C. for 24 hours. After filtering, the recovered material was washed with ethanol and HCl and heat-treated at 550 ° C. for 4 hours to prepare mesoporous silica (KIT-6).

Production Example 2: Carrier containing mesoporous iron oxide (m-Fe ₂ O ₃ )

3 g of iron nitrate nonahydrate, which is an iron precursor, was dispersed in 30 mL of ethanol and 3 g of mesoporous silica (KIT-6) prepared in Preparation Example 1 was added thereto. The mixture was stirred at room temperature for 3 hours, And then heat-treated at 300 ° C for 3 hours to prepare a mixture 1.

Thereafter, 3 g of iron nitrate nonahydrate was dispersed in 30 mL of ethanol, and the mixture 1 was recovered, dispersed, stirred at room temperature, and ethanol was removed to prepare Mixture 2.

The mixture 2 was recovered and then heat-treated at 300 ° C for 3 hours and at 500 ° C for 3 hours to prepare a complex containing iron oxide (Fe ₂ O ₃ ) and KIT-6. Thereafter, the complex was reacted with a 2M NaOH solution to remove the KIT-6, and this procedure was repeated three times for 2 hours each. Thereafter, the resultant was dried overnight in a vacuum oven at room temperature to prepare a carrier (m-Fe ₂ O ₃ ) containing mesoporous iron oxide.

Example 1-1: A mesoporous iron oxide composite (m-FeO) having platinum single atom introduced with 0.08 wt% of platinum by weight _x / Pt _One -0.08 wt%)

After 100 mg of m-Fe ₂ O ₃ of Preparation Example 2 was dispersed in 10 mL of ethanol, 5.31 μL of a platinum precursor chloroplatinic acid hydrate of 40 mg / mL dispersed in water was added. Then, the mixture was stirred at room temperature, ethanol was removed, and the mixture was dried overnight in a vacuum oven at room temperature. The mixture was heat-treated at 400 ° C. for 5 hours and then heat-treated at 200 ° C. for 30 minutes under 10% H ₂ / Ar gas to obtain a platinum single atom-containing mesoporous iron oxide composite (m-FeO _x / Pt ₁ -0.08 wt%).

Example 1-2: A mesoporous iron oxide composite (m-FeO) having platinum single atom incorporated therein having a weight percentage of platinum of 0.2 wt% _x / Pt _One -0.2 wt%)

A platinum precursor chloroplatinic acid hydrate was prepared in the same manner as in Example 1-1 except that 13.30 占 퐇 was used instead of 5.31 占 퐇, thereby obtaining a mesoporous iron oxide composite having platinum single atom incorporated therein containing 0.2wt% of platinum (m-FeO _x / Pt ₁ -0.2 wt%).

Example 1-3: A mesoporous iron oxide composite (platinum single atom-introduced mesoporous iron oxide composite (m-FeO _x / Pt _One -0.4wt%)

Except that 26.65 [mu] L of platinum precursor chloroplatinic acid hydrate was used instead of 5.31 [mu] L of a platinum single atom-containing mesoporous iron oxide complex containing 0.4% by weight of platinum in the same manner as in Example 1-1 (m-FeO _x / Pt ₁ -0.4 wt%).

Example 1-4: A mesoporous iron oxide composite (m-FeO) having platinum single atom introduced with 1 wt% of platinum in weight% _x / Pt _One -1wt%)

Except that 67.04 μL of chloroplatinic acid hydrate was used in place of 5.31 μL of platinum precursor (Example 1). The platinum precursor chloroplatinic acid hydrate was prepared in the same manner as in Example 1-1 except that 67.04 μL of chloroplatinic acid hydrate was used instead of 5.31 μL of platinum precursor chloroplatinic acid hydrate m-FeO _x / Pt ₁ -1 wt%).

Example 1-5: A mesoporous iron oxide complex (m-FeO) having platinum single atom incorporated therein having a platinum content of 1.5 wt% _x / Pt _One -1.5 wt%)

Platinum Precursor A mesoporous iron oxide composite having platinum single atom incorporated therein containing 1.5 wt% of platinum was prepared in the same manner as in Example 1-1 except that 101.07 mu L of chloroplatinic acid hydrate was used instead of 5.31 mu L of chloroplatinic acid hydrate. (m-FeO _x / Pt _{1 -} 1.5 wt%).

Example 1-6: A mesoporous iron oxide complex (m-FeO) having platinum single atom introduced with 2 wt% of platinum in weight% _x / Pt _One -2wt%)

Except that 135.45 占 대신 was used instead of 5.31 占 Ch of chloroplatinic acid hydrate (platinum precursor), a mesoporous iron oxide composite having a platinum single atom incorporated therein containing 2wt% of platinum was obtained in the same manner as in Example 1-1 m-FeO _x / Pt ₁ -2 wt%).

Example 1-7: A mesoporous iron oxide composite (m-FeO) having platinum single atom incorporated therein having a weight percentage of platinum of 4 wt% _x / Pt _One -4 wt%)

Except that 276.54 [mu] L of platinum precursor chloroplatinic acid hydrate was used instead of 5.31 [mu] L of the platinum precursor chloroplatinic acid hydrate. m-FeO _x / Pt ₁ -4 wt%).

Table 1 summarizes the weight percent of platinum in the mesoporous iron oxide composite prepared according to Examples 1-1 to 1-7, the platinum precursor used and its amount.

% By weight of platinum
(wt%) Platinum precursor Platinum precursor use amount
(μL) Example 1-1 0.08 Chloroplatinic acid hydrate 5.31 Examples 1-2 0.2 Chloroplatinic acid hydrate 13.30 Example 1-3 0.4 Chloroplatinic acid hydrate 26.65 Examples 1-4 One Chloroplatinic acid hydrate 67.04 Examples 1-5 1.5 Chloroplatinic acid hydrate 101.07 Examples 1-6 2 Chloroplatinic acid hydrate 135.45 Examples 1-7 4 Chloroplatinic acid hydrate 276.54 Comparative Example 1-1 One Chloroplatinic acid hydrate 98.25

Comparative Example 1-1: A non-porous iron oxide complex (platinum single atom-containing platinum (FeO _x / Pt _One -1wt%)

100 mL of a solution of 1 M iron nitrate nonahydrate, 1 M sodium carbonate, 0.0759 M platinum precursor chloroplatinic acid hydrate was stirred at 50 ° C, pH 8, After synthesis, the synthetic material was allowed to dry at 60 DEG C for 5 hours. The mixture was heat-treated at 400 ° C. for 5 hours and then heat-treated at 200 ° C. for 30 minutes under 10% H ₂ / Ar gas to obtain a non-mesoporous iron oxide composite (FeO _x / Pt ₁ -1 wt%).

Example 2-1: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles incorporated with 0.08 wt% of platinum by weight _x / Pt _One  NPs-0.08 wt%)

50 mL of a mixture of 0.4 M NaOH and ethylene glycol was prepared, and 1 g of platinum precursor chloroplatinic acid hydrate was added and reacted at 160 캜 for 3 hours to prepare a platinum precursor mixed solution. 100 mg of m-Fe ₂ O ₃ of Production Example 2 was dispersed in 10 mL of ethanol, 21.26 μL of the platinum precursor mixture solution was added, and sonication was performed for 1 hour. Thereafter, the mixture was centrifuged at 7000 rpm and dried overnight in a vacuum oven to prepare a mesoporous iron oxide composite (m-FeO _x / Pt ₁ NPs-0.08 wt%) having platinum nanoparticles of 0.08 wt% .

Example 2-2: A mesoporous iron oxide composite (m-FeO) containing platinum nano particles of 0.2 wt% _x / Pt _One  NPs-0.2 wt%)

Platinum precursor mixed solution of platinum the platinum nano-particles is introduced containing 0.2wt% in the same manner as in Example 2-1 except for using, instead of 53.22μL 21.26μL mesoporous composite iron oxide (FeO _m-x / Pt ₁ NPs-0.2 wt%).

Example 2-3: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles introduced with 0.4 wt% _x / Pt _One  NPs-0.4wt%)

Except that the platinum precursor mixture solution was replaced by 106.66 μL instead of 21.26 μL, platinum nanoparticles containing 0.4 wt% of platinum were introduced in the same manner as in Example 2-1, and the mesoporous iron oxide complex (m-FeO _x / Pt ₁ NPs-0.4 wt%).

Example 2-4: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles introduced with 1 wt% of platinum in weight% _x / Pt _One  NPs-1 wt%)

Except that 268.2 μL of platinum precursor mixture solution was used instead of 21.26 μL of platinum precursor mixture solution in Example 1. The same procedure as in Example 2-1 was repeated except that platinum nanoparticles containing 1 wt% of platinum were introduced into the mesoporous iron oxide complex (m-FeO _x / Pt ₁ NPs-1 wt%).

Example 2-5: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles introduced with 1.5 wt% of platinum in weight% _x / Pt _One  NPs-1.5 wt%)

Platinum precursor mixed solution of platinum the platinum nano-particles is introduced containing 1.5wt% in the same manner as in Example 2-1 except for using, instead of 404.4μL 21.26μL mesoporous composite iron oxide (FeO _m-x / Pt ₁ NPs-1.5 wt%).

Example 2-6: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles incorporated with 2 wt% of platinum in weight% _x / Pt _One  NPs-2 wt%)

Except the platinum precursor mixture solution was used in place of the 542.0μL 21.26μL in Example 2-1 in the same manner as the platinum 2wt% of the platinum nano-particles it is introduced include mesoporous iron oxide complex (m-FeO _x / Pt ₁ NPs-2 wt%).

Example 2-7: A mesoporous iron oxide composite (m-FeO) having platinum nanoparticles incorporated therein having a weight percentage of platinum of 4 wt% _x / Pt _One  NPs-4 wt%)

(M-FeO _x / Pt ₁₎ containing platinum nanoparticles containing 4 wt% of platinum was prepared in the same manner as in Example 2-1, except that 1106.6 μL was used instead of 21.26 μL of the platinum precursor mixture solution. NPs-4wt%).

Table 2 summarizes the weight percent of platinum in the mesoporous iron oxide composite prepared according to Examples 2-1 to 2-7, the platinum precursor mixed solution used and its amount.

% By weight of platinum
(wt%) Platinum precursor mixture solution Platinum Precursor Mix Solution Amount (μL) Example 2-1 0.08 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 21.26 Example 2-2 0.2 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 53.22 Example 2-3 0.4 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 106.66 Examples 2-4 One Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 268.2 Example 2-5 1.5 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 404.4 Examples 2-6 2 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 542.0 Examples 2-7 4 Chloroplatinic acid hydrate / Ethylene glycol / sodium hydroxide mixed solution 1106.6

[Test Example]

Test Example 1: X-ray diffraction (XRD) pattern analysis

2 is a graph showing an X-ray diffraction (XRD) pattern of m-FeO _x prepared according to Example 1. FIG.

Referring to FIG. 2, it was confirmed that the XRD peak of Fe ₂ O ₃ coincided with the XRD peak of Fe ₂ O ₃ . It was confirmed that FeO _x has a partially reduced structure based on an α-Fe ₂ O ₃ structure having JCPDS No. 89-2810.

Test Example 2: Transmission electron microscope (TEM) image analysis

3 is a TEM image of a platinum single atom-introduced mesoporous iron oxide composite (m-FeO _x / Pt ₁ ) of Example 1. Fig.

Referring to FIG. 3, it was confirmed that the mesoporous iron oxide complex carrying the platinum single atom was synthesized at a size of several hundred nanometers having mesopores.

Test Example 3: Surface area and pore size analysis

4 is a graph showing a BET isotherm graph and pore size of a carrier (m-Fe ₂ O ₃ ) containing mesoporous iron oxide of Production Example 2. FIG.

Referring to FIG. 4, it was confirmed that the support of Production Example 2 had a pore size of 3.5 nm with a surface area of 106.63 m ² / g.

Therefore, the carrier prepared according to Production Example 2 is judged to have a high surface area.

Test Example 4: Fourier-transform infrared spectroscopy (FT-IR) analysis

5 is a graph of Fourier-transform infrared spectroscopy (FT-IR) measurement of a mesoporous iron oxide composite (m-FeO _x / Pt ₁ )

The CO gas is a gas with excellent bonding with platinum. When CO molecules are bonded to platinum to which two or more platinum atoms are bonded, the FT-IR has a peak of the linear CO. On the other hand, it was confirmed that when CO molecules are bonded to a substance in which a platinum single atom is introduced, it is redshift compared to the CO peak in the bulk platinum.

Referring to Figure 5, the m-FeO _x / Pt ₁ a of 0.4wt% platinum was introduced, most of the platinum is found that the existing single reactor, of 2wt% platinum is introduced into the m-FeO _x / Pt ₁ in It was confirmed that a platinum single atom and two or more platinum atoms exist in a cluster form.

Test Example 5: High angle annular dark field-scanning transmission electron microscopy (HAADF-STEM) analysis

6 (a), 6 (b) and 6 (c) are graphs showing the results of measurement of HAADF of m-FeO _x / Pt ₁ -2 wt% in which platinum single atom-containing mesoporous iron oxide complex containing 2 wt% (M-FeO _x / Pt NPs-2 wt%), platinum nanoparticles containing 2 wt% of platinum of Example 2-6, and (d) HAADF-STEM image.

Referring to FIG. 6 (c), it can be seen that FeO _x has a lattice structure and a platinum single atom exists between the lattice structures. As can be seen from (f), it can be confirmed that the platinum nanoparticle-introduced FeO _x does not have a platinum single atom.

Test Example 6: Absorption Spectrum Analysis

To compare the mesoporous iron oxide complex (m-FeO _x / Pt ₁ ) with platinum single atom introduced and the mesoporous iron oxide complex (m-FeO _x / Pt NPs) with platinum nanoparticles, ', 5,5'-tetramethylbenzidine (TMB) was performed.

7 (a) is an absorption spectrum of a platinum single atom-introduced mesoporous iron oxide complex (m-FeO _x / Pt ₁ ) of Example 1, and (b) is an absorption spectrum of a mesoporous Iron oxide complex (m-FeO _x / Pt NPs). 7 (c) is a graph showing Ab _Pt1 / Ab _NPs according to weight percent of platinum.

7 (a) and (b), it was confirmed that m-FeO _x / Pt ₁ had higher activity than m-FeO _x / Pt NPs when a low wt% platinum was introduced.

As a result of comparing the absorbance at 652 nm, which has the highest peak in the absorption spectrum, it was confirmed that the absorbance was 4.5 times or more higher at 0.08 wt%, and as the amount of platinum introduced increased, the relative amount of single atoms decreased It was confirmed that the activity similar to that of the platinum nanoparticles was observed.

FIG. 8 is a graph showing the results of measurement of the permeability of a mesoporous iron oxide composite (m-FeO _x / Pt ₁ -1 wt%) containing 1 wt% of platinum prepared according to Example 1-4 and 1 wt% of platinum prepared according to Comparative Example 1-1 (FeO _x / Pt _{1 - 1} wt%) which is not mesoporous.

Referring to Figure 8, the mesoporous oxide composite _{(m-FeO x / Pt 1} -1wt%) compared to the non-porous with the iron oxide complex of 1wt% platinum meso _{(FeO x / Pt 1 -1wt%} ) three times , And it was confirmed that it has high activity.

The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

Claims (18)

A carrier comprising mesoporous iron oxide having mesopores; And
A catalyst supported on the outer surface of the mesoporous iron oxide; and a catalyst supported on a surface in contact with the mesopores therein,
Wherein the catalyst comprises a platinum single atom,
Wherein the mesoporous iron oxide has a three-dimensional skeleton, the mesopores formed by the three-dimensional skeleton,
Wherein the mesoporous iron oxide has a three-dimensional network structure,
Wherein the mesopores are formed by the mesoporous three-dimensional network structure and are connected successively,
Wherein the size of the mesopores is 2 to 20 nm,
Wherein the iron oxide is Fe ₂ O ₃ ,
Wherein the weight percentage of platinum carried on the mesoporous iron oxide composite is 0.01 to 10 wt%. delete delete delete delete delete delete delete delete (a-1) producing mesoporous silica (KIT-6);
(a-2) preparing a mixture comprising the mesoporous silica (KIT-6), an iron precursor, and a solvent;
(a-3) heat-treating the mixture to prepare a composite comprising iron oxide and KIT-6;
(a-4) removing the KIT-6 from the complex to prepare a carrier comprising mesoporous iron oxide having mesopores;
(b) preparing a mixture comprising said support, a platinum precursor and a solvent; And
(c) preparing a mesoporous iron oxide composite comprising a catalyst supported on the outer surface of the mesoporous iron oxide and a catalyst supported on a surface in contact with the mesopores therein, the mixture being stirred, reduced and dried, ; ≪ / RTI >
Wherein the catalyst comprises a platinum single atom,
Wherein the mesoporous iron oxide has a three-dimensional skeleton, the mesopores formed by the three-dimensional skeleton,
Wherein the mesoporous iron oxide has a three-dimensional network structure,
Wherein the mesopores are formed by the mesoporous three-dimensional network structure and are connected successively,
Wherein the size of the mesopores is 2 to 20 nm,
Wherein the iron oxide is Fe ₂ O ₃ ,
Wherein the weight percentage of platinum carried on the mesoporous iron oxide composite is 0.01 to 10 wt%
A method for producing a mesoporous iron oxide composite. delete delete 11. The method of claim 10,
In step (a-2)
Wherein the iron precursor comprises at least one selected from the group consisting of Iron nitrate nonahydrate, Iron chloride hexahydrate and Iron chloride tetrahydrate. ≪ / RTI > 11. The method of claim 10,
In step (a-4)
Wherein the KIT-6 is removed by sodium hydroxide (NaOH). 11. The method of claim 10,
Characterized in that the platinum precursor comprises at least one selected from the group consisting of chloroplatinic acid hydrate, sodium hexachloroplatinate hexahydrate and potassium hexachloroplatinate. Wherein the mesoporous iron oxide composite is produced by a method comprising the steps of: 11. The method of claim 10,
The reduction reaction of step (c)
(c-1) heat-treating; And
(c-2) the step of annealing under a 10% H ₂ / Ar gas; method of producing a mesoporous oxide complex comprising the. 17. The method of claim 16,
Wherein the heat treatment is performed in a temperature range of 100 ° C to 500 ° C. 11. The method of claim 10,
Wherein the solvent is a polar solvent.

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