KR102209684B1 - Surface-modified boron nitride structure and method of manufacturing thereby - Google Patents

Abstract

The boron nitride nanostructure according to an embodiment of the present invention forms defects through surface modification.

Description

Surface-modified boron nitride nanostructure and its manufacturing method {SURFACE-MODIFIED BORON NITRIDE STRUCTURE AND METHOD OF MANUFACTURING THEREBY}

The present invention relates to a boron nitride nanostructure having a modified surface and a method for producing the same, and more particularly, to prepare a boron nitride nanostructure having high redox reactivity by modifying the surface of the boron nitride nanostructure.

Boron nitride nanotubes (BNNTs), a representative material of boron nitride nanostructures, are new generation nanomaterials, and are characterized by excellent mechanical strength/electrical insulation/thermal conductivity/piezoelectric/neutron shielding/catalytic properties, and the electronics industry/energy including IT/IoT. /Environment/space/nuclear power and biomedical, etc. are expected to play an important role as a core basic material for industries.

Currently, the application product of boron nitride nanotubes (BNNT) in the early stages taking the lead in the global market through the development of original manufacturing technologies/processes/systems for mass production of boron nitride nanotubes (BNNT) nanopowder that are currently inexpensive worldwide. It is necessary to secure the originality of the product early, to increase the competitiveness of the boron nitride nanotube (BNNT) material/manufacturing technology developed in Korea, to promote industrial utilization and expand overseas markets.

In particular, as the “new climate system” was launched through the Paris Agreement in 2015, countries around the world are seeking measures to reduce high-intensity greenhouse gas emissions and to convert toxic gases.

Reducing carbon monoxide (CO), hydrocarbons (HC), and nitrogen oxides (NOx), which are major pollutants of automobile exhaust gas, is a very important factor in countermeasures against fine dust, which is a serious social/environmental problem worldwide. In the case of precious metals (eg Pt, Pd, Rh), which are frequently used as catalysts for oxidation or reduction of such exhaust gas, prices are expected to continue to rise in the future due to rising demand and limited supply. (As of 2018, the price of Pt is $32,673/kg, the price of Pd is $35,610/kg, and the price of Rh is $39,224/kg.)

Therefore, development of a catalyst that increases the redox reaction rate of environmentally harmful gases while reducing the amount of noble metal catalyst must be devised.

Non-precious metal catalysts (e.g., Ni, Fe, Co) have been studied to replace noble metal catalysts, but they do not show the same reaction rate as the noble metal catalysts. As the particles are aggregated, the specific surface area of the metal catalyst particles is greatly reduced. Accordingly, a decrease in the redox reaction rate is a problem.

In the case of heterogeneous supported catalysts, metal oxides are widely used, but problems such as sintering and oxidation state changes at high temperatures were found.

As described above, various materials have been applied and developed so far, but problems such as limitation of conversion rate, decrease in activity due to changes in catalyst structure, and high cost related to regeneration have been raised.

Compared with this, boron nitride nanotubes (BNNTs) exhibit characteristics such as very high specific surface area, ease of surface structure change, and thermal/chemical stability, and thus propane oxidative dehydrogenation reaction, which is very important in oil refining process along with redox reaction of harmful gases. It has attracted a lot of interest in industrial applications such as propylene production using

However, boron nitride nanotubes (BNNTs) having very good crystallinity have low reactivity and are therefore practically ineffective as a catalyst.

Therefore, there is a need for a catalyst using boron nitride nanotubes (BNNT), which is more economical and highly efficient, with increased chemical reactivity of boron nitride nanotubes (BNNT).

Republic of Korea Patent Publication No. 10-2015-0143798 (2015.12.23)

An object of the present invention is to provide a low-cost and high-efficiency catalyst by modifying the surface of the boron nitride nanostructure, increasing the chemical reactivity, and placing a very small amount of metal nanoparticles on the surface of the boron nitride nanostructure.

The problem to be solved by the present invention is not limited to the problem(s) mentioned above, and another problem(s) that is not mentioned will be clearly understood by those skilled in the art from the following description.

The boron nitride nanostructure according to an embodiment of the present invention forms defects through surface modification.

In addition, the boron nitride nanostructure according to an embodiment of the present invention is selected from the group consisting of boron nitride nanotubes (BNNT), boron nitride nanosheets (BNNS), and hexagonal boron nitride (h-BN).

In addition, in the boron nitride nanostructure according to an embodiment of the present invention, metal nanoparticles are formed in the defect.

In addition, the metal nanoparticles according to an embodiment of the present invention include platinum (Pt), palladium (Pd), gold (Au), silver (Ag), iron (Fe), cobalt (Co), nickel (Ni), It is selected from the group consisting of copper (Cu), chromium (Cr), molybdenum (Mo), tungsten (W), ruthenium (Ru), rhodium (Rh), iridium (Ir), vanadium (V), and alloys thereof.

In addition, the metal nanoparticles according to an embodiment of the present invention are included in an amount of 0.1 to 15 wt%.

In addition, the metal nanoparticles according to an embodiment of the present invention are included in an amount of 0.1 to 3 wt%.

In addition, the method for modifying the surface of the boron nitride nanostructure according to an embodiment of the present invention,

Mixing the boron nitride nanostructure with a neutral solution to form a first mixture, mixing the first mixture with a metal dispersion solution to form a second mixture, and ultrasonically dispersing the second mixture to form the boron nitride nano Forming a defect on the surface of the structure.

In addition, the formation of defects on the surface of the boron nitride nanostructure through the ultrasonic dispersion according to an embodiment of the present invention is formed using microbubbles.

In addition, after the step of forming a defect on the surface of the boron nitride nanostructure according to an embodiment of the present invention, a step of forming metal nanoparticles on the defect is further included.

In addition, the ultrasonic dispersion according to an embodiment of the present invention is performed for 1 to 10 hours.

In addition, the formation of metal nanoparticles in the defect according to an embodiment of the present invention is formed by physical bonding by reducing a metal precursor.

According to an embodiment of the present invention, in the boron nitride nanostructure, defects are formed through surface modification of the boron nitride nanostructure, and metal nanoparticles are attached to the surface, so that it is more stable and efficient in high temperature and extreme environments. It can provide a high catalyst.

1 is a TEM image of a boron nitride nanotube (BNNT) before metal bonding according to a first embodiment of the present invention.
2 is a TEM image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
3 is an EDS analysis electronic image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
4 is an EDS analysis layered image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
5 is a boron atom EDS analysis image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
6 is a nitrogen atom EDS analysis image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
7 is an EDS analysis image of a platinum atom of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
8 is an EDS analysis graph of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention.
9 is a TEM image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
10 is an EDS analysis electronic image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention,
11 is an EDS analysis layered image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
12 is a boron atom EDS analysis image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
13 is a nitrogen atom EDS analysis image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
14 is a palladium atom EDS analysis image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
15 is an EDS analysis graph of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention.
16 is a TEM image of a boron nitride nanotube catalyst (Pd-BNNT) according to a sixth embodiment of the present invention.
17 is a TEM image of a boron nitride nanosheet catalyst (Pt-BNNS) according to a fourth embodiment of the present invention.
18 is a graph of CO conversion rates according to the first, second, fourth, and fifth embodiments of the present invention.
19 is a graph of CO conversion of the low-concentration boron nitride nanotube catalysts according to the second, third, fifth and sixth embodiments of the present invention.
20 is a graph of CO conversion over time of the boron nitride nanotube catalyst (Pd-BNNT) according to the sixth embodiment of the present invention.
21 is a graph showing the amount of CO ₂ generated over time of the boron nitride nanotube catalyst (Pd-BNNT) according to the sixth embodiment of the present invention.

Advantages and/or features of the present invention, and a method of achieving them will become apparent with reference to the embodiments described later in detail together with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments make the disclosure of the present invention complete, and common knowledge in the technical field to which the present invention pertains. It is provided to completely inform the scope of the invention to those who have, and the invention is only defined by the scope of the claims. The same reference numerals refer to the same elements throughout the specification.

In general, unmodified boron nitride nanotubes have excellent thermal and chemical stability, so their application potential as a remover or adsorbent for CO, HC, Nox, and other pollutants including CO ₂ is very high, but the surface is too stable. Therefore, it is also true that there is a limit to use as a catalyst. Accordingly, the present inventors prepared a highly efficient boron nitride nanostructure catalyst by increasing the reactivity through surface modification of boron nitride nanostructures, particularly boron nitride nanotubes, and attaching metal nanoparticles.

In addition, the present invention was completed by confirming the high experimental effect of the prepared boron nitride nanostructure catalyst.

The boron nitride nanostructure according to an embodiment of the present invention is characterized in that a defect is formed through surface modification of the boron nitride nanostructure.

In addition, the boron nitride nanostructure according to an embodiment of the present invention is characterized in that the metal nanoparticles are formed in the defect, and the metal nanoparticles are contained in an amount of 0.1 to 30 wt%.

In addition, the boron nitride nanostructure according to an embodiment of the present invention is characterized in that the metal nanoparticles are formed in the defect, and the metal nanoparticles are contained in an amount of 0.1 to 15 wt%.

Preferably, it may be included in an amount of 0.1 to 10 wt%, and more preferably, it may be included in an amount of 0.1 to 5 wt%.

In addition, more preferably 0.1 to 3 wt% may be included, and even more preferably 0.1 to 2.0 wt%.

In addition, the metal nanoparticles according to an embodiment of the present invention include platinum (Pt), palladium (Pd), gold (Au), silver (Ag), iron (Fe), cobalt (Co), nickel (Ni), Any one selected from the group consisting of copper (Cu), chromium (Cr), molybdenum (Mo), tungsten (W), ruthenium (Ru), rhodium (Rh), iridium (Ir), vanadium (V), and alloys thereof However, the present invention is not limited thereto.

In addition, the boron nitride nanostructure according to an embodiment of the present invention may be any one selected from the group consisting of boron nitride nanotubes (BNNT), boron nitride nanosheets (BNNS), and hexagonal boron nitride (h-BN). However, the present invention is not limited thereto.

In addition, the method for modifying the surface of the boron nitride nanostructure according to an embodiment of the present invention comprises the steps of forming a first mixture by mixing the boron nitride nanostructure with a neutral solution, and mixing a metal dispersion solution with the first mixture. Thus forming a second mixture, forming defects on the surface of the boron nitride nanostructure by ultrasonically dispersing the second mixture, and forming metal nanoparticles in the defects.

In addition, the formation of the defect through the ultrasonic dispersion according to an embodiment of the present invention is characterized in that it is formed using microbubbles.

Specifically, when the second mixture is subjected to ultrasonic treatment, microbubbles are formed on the surface of the boron nitride nanostructure, and the microbubbles are bubbled with dissolved gas due to negative pressure generated by ultrasonic waves, resulting in continuous ultrasonic waves. During repeated growth, the liquid enters the bubble and bursts under pressure (cavitation phenomenon). At this time, a defect is created through the local energy generated on the surface, and the metal precursor in the second mixture is reduced to physically bond with the defect.

The metal precursor may be any one selected from metal precursors of the metal nanoparticles listed above, but the present invention is not limited thereto.

Hereinafter, the present invention will be described in more detail through specific examples. However, the following examples are presented by way of example to aid understanding of the present invention, and the scope of the present invention should not be construed as being limited thereto.

Generally manufactured boron nitride nanotube (BNNT) raw material is inert and does not have polarity, so it is not well dispersed, and it contains impurities such as carbon, boron and metal oxides during manufacturing, which acts as a factor that lowers the efficiency of the catalyst. Therefore, it is difficult to use directly. Therefore, first, purified boron nitride nanotubes (BNNT) are obtained, and boron nitride nanotubes (BNNT) containing metal nanoparticles are obtained through surface modification.

Example 1: Preparation of purified boron nitride nanotubes (BNNT)

Add 1 g of boron nitride nanotube (BNNT) raw material to 200 ml of 3M HCl to form a first solution, and disperse the first solution for 2 hours with an ultrasonic disperser to prevent unwanted residue remaining on the surface of boron nitride nanotubes (BNNT). Metal or metal oxide impurities were removed.

Then, the first solution was stirred at 90°C for 3 hours using a magnetic stirrer under a nitrogen atmosphere, and then 1M nitric acid (100 mL) was added to form a second solution, and the second solution was oxidized at 90°C for 3 hours. By reacting, unwanted metal or metal oxide impurities were additionally removed.

The second solution was filtered to obtain boron nitride nanotubes (BNNT), washed with a neutral solution (DI Water) until neutral, and dried at 90°C to prepare purified boron nitride nanotubes (BNNT). .

In addition, in order to increase the purity of the purified boron nitride nanotubes (BNNT), heat treatment by heating at 800° C. for 2 hours in an air atmosphere, mixing with a neutral solution (DI Water) at 90° C. to dissolve water-soluble impurities. After washing with the step and neutral solution (DI Water) and drying at 90°C, unreacted boron, carbon, etc. were removed to prepare an additionally purified boron nitride nanotube (BNNT).

Example 2: Preparation of boron nitride nanotube catalyst (Pt-BNNT)

Put 250 mg of boron nitride nanotubes (BNNT) obtained through the first embodiment in a neutral solution (DI Water (250 ml)) and disperse using an ultrasonic disperser to form microbubbles on the surface of the boron nitride nanotubes (BNNT) ( Micro-Bubble).

A defect induced by cavitation is formed on the surface of the boron nitride nanotube (BNNT) through local energy generated when the generated micro-bubble bursts by pressure.

In order to bind the metal nanoparticles to the defect, 1.3 ml of H ₂ PtCl ₆ (H ₂ PtCl ₆ 8 wt% in H ₂ O) was mixed in the dispersion solution and then 10 hours using an ultrasonic disperser (40 kHz, 100 W). During the reaction, a solution is prepared.

The prepared solution was filtered to remove unreacted Pt particles and dried at 80° C. for 12 hours to prepare a boron nitride nanotube catalyst (Pt-BNNT).

Example 3: Preparation of low-concentration boron nitride nanotube catalyst (Pt-BNNT)

A low concentration boron nitride nanotube catalyst (Pt-BNNT) was prepared by limiting the amount of platinum to be added in the second embodiment to 2.06 wt% based on pure boron nitride nanotubes (BNNT).

Example 4: Preparation of boron nitride nanosheet catalyst (Pt-BNNS)

Add 250 mg of hexagonal boron nitride (h-BN) to a neutral solution (DI Water (250 ml)) and disperse using an ultrasonic disperser to create a micro-bubble on the surface of the boron nitride nanotube (BNNT). do.

A defect induced by cavitation is formed on the surface of the boron nitride nanotube (BNNT) through local energy generated when the generated micro-bubble bursts by pressure.

In order to bind the metal nanoparticles to the defect, 1.3 ml of H ₂ PtCl ₆ (H ₂ PtCl ₆ 8 wt% in H ₂ O) was mixed in the dispersion solution and then 10 hours using an ultrasonic disperser (40 kHz, 100 W). During the reaction, a solution is prepared.

The prepared solution was filtered to remove unreacted Pt particles and dried at 80° C. for 12 hours to prepare a boron nitride nanosheet catalyst (Pt-BNNS).

Example 5: Preparation of boron nitride nanotube catalyst (Pd-BNNT)

Put 250 mg of boron nitride nanotubes (BNNT) obtained in Example 1 into a neutral solution (DI Water (250 ml)) and disperse using an ultrasonic disperser to form a BNNT solution, and the boron nitride nanotubes (BNNT) surface It creates a micro-bubble.

A defect induced by cavitation is formed on the surface of the boron nitride nanotube (BNNT) through local energy generated when the generated micro-bubble bursts by pressure.

In order to bind the metal nanoparticles to the defect, 125 mg of Pd(NO ₃ ) ₂ ·xH ₂ O powder (Pd content, 40%) was put in a neutral solution (DI water (125 ml)) and an ultrasonic disperser (40 kHz, 100). W) to obtain a Pd dispersion solution (Pd(NO ₃ ) ₂ xH ₂ O powder in Di Water-2.5 mg/ml, Pd in DI Water-1 mg/ml) and mix the Pd dispersion solution with the BNNT solution. After mixing, the mixture was reacted for 10 hours using an ultrasonic disperser (40 kHz, 100 W) to prepare a mixed solution.

The mixed solution was filtered to remove unreacted Pd particles and dried at 80° C. for 12 hours to prepare a boron nitride nanotube catalyst (Pd-BNNT).

Example 6: Preparation of low-concentration boron nitride nanotube catalyst (Pd-BNNT)

A low concentration boron nitride nanotube catalyst (Pd-BNNT) was prepared by limiting the amount of palladium added in the fifth embodiment to 2.31 wt% with respect to pure boron nitride nanotubes (BNNT).

Example 7: Analysis of results

1 is a TEM image of a boron nitride nanotube (BNNT) before metal bonding according to a first embodiment of the present invention.

As shown in FIG. 1, it can be seen that nothing is bonded to the surface of the boron nitride nanotube (BNNT).

2 is a TEM image of a boron nitride nanotube catalyst (Pt-BNNT) according to a second embodiment of the present invention, and FIG. 3 is a TEM image of a boron nitride nanotube catalyst (Pt-BNNT) according to the second embodiment of the present invention. EDS analysis electronic image, Figure 4 is an EDS analysis layered image of the boron nitride nanotube catalyst (Pt-BNNT) according to the second embodiment of the present invention, Figure 5 is a boron nitride nanoparticle according to the second embodiment of the present invention Boron atom EDS analysis image of the tube catalyst (Pt-BNNT), Figure 6 is a nitrogen atom EDS analysis image of the boron nitride nanotube catalyst (Pt-BNNT) according to the second embodiment of the present invention, Figure 7 is the present invention Is an EDS analysis image of a platinum atom of the boron nitride nanotube catalyst (Pt-BNNT) according to the second embodiment of the present invention, and FIG. 8 is an EDS analysis of the boron nitride nanotube catalyst (Pt-BNNT) according to the second embodiment of the present invention. It is a graph.

As shown in FIG. 2, it can be seen that platinum (Pt) is attached to the surface of the boron nitride nanotube (BNNT).

In addition, as shown in FIGS. 3 to 7, the distribution of the material contained in the boron nitride nanotube catalyst (Pt-BNNT) can be confirmed, and as shown in Table 1 below, the platinum (Pt) particles are 10.35wt%. You can see that is included.

matter wt% Atomic ratio Boron (B) 45.70 56.99 Nitrogen (N) 43.95 42.29 Platinum (Pt) 10.35 0.72 Total 100 100

9 is a TEM image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention, and FIG. 10 is a TEM image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention. An EDS analysis electronic image, FIG. 11 is an EDS analysis layered image of a boron nitride nanotube catalyst (Pd-BNNT) according to a fifth embodiment of the present invention, and FIG. 12 is a boron nitride nanoparticle according to the fifth embodiment of the present invention. Boron atom EDS analysis image of the tube catalyst (Pd-BNNT), FIG. 13 is a nitrogen atom EDS analysis image of the boron nitride nanotube catalyst (Pd-BNNT) according to the fifth embodiment of the present invention, and FIG. 14 is the present invention Is a palladium atom EDS analysis image of the boron nitride nanotube catalyst (Pd-BNNT) according to the fifth embodiment of the present invention, and FIG. 15 is an EDS analysis of the boron nitride nanotube catalyst (Pd-BNNT) according to the fifth embodiment of the present invention It is a graph.

As shown in FIG. 9, it can be seen that palladium (Pd) is attached to the surface of the boron nitride nanotube (BNNT).

In addition, as shown in FIGS. 10 to 15, the distribution of the material contained in the boron nitride nanotube catalyst (Pd-BNNT) can be confirmed, and palladium (Pd) particles are 1.14 wt% as shown in Table 2 below. You can see that it is included. In addition, carbon (C) was detected by a carbon layer used as a grid of TEM, and oxygen (O) was detected when the sample was exposed to air.

matter wt% Atomic ratio Boron (B) 9.54 11.09 Carbon (C) 65.68 68.74 Nitrogen (N) 13.14 11.79 Oxygen(0) 10.50 8.27 Palladium (Pd) 1.14 0.13 Total 100 100

16 is a TEM image of a boron nitride nanotube catalyst (Pd-BNNT) according to a sixth embodiment of the present invention.

As shown in FIG. 16, it can be seen that the palladium (Pd) particles of low concentration are attached to the surface of the boron nitride nanotube (BNNT).

Table 3 shows the initial input amount of each catalyst particle to the boron nitride nanotubes (BNNT) and the boron nitride nanotube catalysts (BNNT-Pt or Pd) analyzed by ICP (Inductively Coupled Plasma)-AES (Atomic Emission Spectroscopy). ) Is a table showing the amount of catalyst particles attached to.

Specifically, as shown in Table 3, it can be seen that 0.52 wt% of palladium (Pd) particles are attached.

Amount of catalyst particles initially added (wt%) On boron nitride nanotubes (BNNT)
Amount of attached catalyst particles (wt%) Pt-BNNT 2.06 0.21 Pd-BNNT 2.31 0.52

At this time, the amount of Pd nanoparticles initially added was applied at a concentration of 2.31 wt% with respect to the boron nitride nanotubes (BNNT), but it can be confirmed that only 0.52 wt% of the boron nitride nanotubes (BNNT) were finally attached. , This shows that not all of the added initial material is adsorbed on the boron nitride nanotubes (BNNT).

As shown in Table 3, it can be seen that 0.21 wt% of platinum (Pt) particles are attached to the boron nitride nanotubes (BNNT).

17 is a TEM image of a boron nitride nanosheet catalyst (Pt-BNNS) according to a fourth embodiment of the present invention.

18 is a graph of CO conversion according to the first, second, fourth and fifth embodiments of the present invention.

As shown in FIG. 18, in the case of pure boron nitride nanotubes (BNNT), CO conversion hardly occurs, and in the case of pure boron nitride nanosheets (BNNS), the reaction is exhibited at 250°C or higher, but the conversion rate cannot exceed 20% The limits are clear.

On the other hand, the boron nitride nanotube catalyst (Pd-BNNT, Pt-BNNT) and the boron nitride nanosheet catalyst (Pt-BNNS) according to the second, fourth and fifth embodiments of the present invention are 150°C. Above, the conversion rate is over 90%.

In the case of pure boron nitride nanostructures, the reactivity is low, so the role as a catalyst is limited. This is because it shows the CO conversion rate.

19 is a graph of CO conversion of the low-concentration boron nitride nanotube catalyst according to the second, third, fifth and sixth embodiments of the present invention.

As shown in FIG. 19, it can be seen that there is no difference in the CO conversion rate compared to the case where the catalyst particles of a high concentration are attached even though the catalyst particles of a low concentration are attached to the boron nitride nanotubes (BNNT).

This is because the catalytic effect of the boron nitride nanotube (BNNT) itself is increased through the surface modification of the boron nitride nanotube (BNNT).

20 is a graph of the CO conversion rate over time of the boron nitride nanotube catalyst (Pd-BNNT) according to the sixth embodiment of the present invention, and FIG. 21 is a boron nitride nanotube catalyst (Pd-BNNT) according to the sixth embodiment of the present invention. -BNNT) is a graph showing the amount of CO ₂ produced over time.

Referring to FIG. 20, it can be seen that the efficiency of the CO conversion rate does not decrease even over time.

This is because the boron nitride nanotubes (BNNTs) serve as a support and at the same time as a catalyst.

The boron nitride nanotube (BNNT) used as a support has features such as high specific surface area, high thermal conductivity, high chemical stability, and improved flowability of reactants due to high porosity and maintenance.

For this reason, there are relatively few problems such as deformation and oxidation of the catalyst material, and there is an effect that the efficiency of the CO conversion rate does not decrease even over time.

In addition, the boron nitride nanotubes (BNNT) are very light and have a relatively high catalytic effect per unit mass, and thus exhibit a high CO conversion rate.

Even with reference to the amount of CO ₂ generation shown in FIG. 21, it can be seen that the efficiency of the CO conversion rate does not decrease.

Although the specific embodiments according to the present invention have been described so far, various modifications are possible without departing from the scope of the invention. Therefore, the scope of the present invention should not be defined by being limited to the described embodiments, and should be defined not only by the claims to be described later, but also by the claims and their equivalents.

As described above, although the present invention has been described by the limited embodiments and drawings, the present invention is not limited to the above embodiments, which is various modifications and variations from these descriptions to those of ordinary skill in the art Transformation is possible. Therefore, the idea of the present invention should be grasped only by the claims set forth below, and all equivalent or equivalent modifications thereof will be said to belong to the scope of the inventive idea.

Claims (11)

In the boron nitride nanostructure,
The boron nitride nanostructure is a surface that forms defects through surface modification,
Metal nanoparticles are formed in the defect,
The defect is formed by micro-bubbles formed on the surface,
The metal nanoparticles are any one metal selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), and vanadium (V).
Boron nitride nanostructure with modified surface.
The method of claim 1,
The boron nitride nanostructure is any one selected from the group consisting of boron nitride nanotubes (BNNT), boron nitride nanosheets (BNNS), and hexagonal boron nitride (h-BN). Nanostructure.
delete delete The method of claim 1,
The surface-modified boron nitride nanostructures, characterized in that the metal nanoparticles are contained in an amount of 0.1 to 15 wt%.
The method of claim 1,
The surface-modified boron nitride nanostructures, wherein the metal nanoparticles are contained in an amount of 0.1 to 3 wt%.
In the method for modifying the surface of the boron nitride nanostructure,
Mixing the boron nitride nanostructures with a neutral solution to form a first mixture;
Forming a second mixture by mixing a metal dispersion solution with the first mixture;
Ultrasonically dispersing the second mixture to form defects on the surface of the boron nitride nanostructure; And
Including the step of forming metal nanoparticles in the defect,
The formation of defects on the surface of the boron nitride nanostructure through the ultrasonic dispersion is formed using microbubbles,
The metal nanoparticles are any one metal selected from the group consisting of palladium (Pd), platinum (Pt), rhodium (Rh), and vanadium (V).
Method for surface modification of boron nitride nanostructures.
delete delete The method of claim 7,
The ultrasonic dispersion is a method for surface modification of a boron nitride nanostructure, characterized in that carried out for 1 to 10 hours.
The method of claim 7,
The formation of metal nanoparticles in the defect is a method for surface modification of a boron nitride nanostructure, characterized in that the metal precursor is reduced and formed by physical bonding.

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