KR101311708B1 - Bulky nanoporous oxide materials and manufacturing method of the same - Google Patents

Abstract

The present invention includes the steps of preparing an oxide-based nanoporous powder, filling the oxide-based nanoporous powder into a mold and setting it in a chamber of a discharge plasma sintering apparatus, vacuuming the inside of the chamber to reduce the pressure, and Applying a direct current pulse while pressing the nanoporous powder to increase the target sintering temperature lower than the melting temperature of the oxide nanoporous powder, and pressing the oxide nanoporous powder at the sintering temperature to press the oxide nanoparticle. The present invention relates to a bulk oxide-based nanoporous porous body prepared by discharge plasma sintering of a porous powder and to cooling the temperature of the chamber to obtain a sintered body, and to a bulk oxide-based nanoporous porous body produced thereby. According to the present invention, it is possible to implement the bulked oxide-based nanoporous porous body in the form of agglomerates, not in powder form.

Description

Bulk-type nanoporous porous body and its manufacturing method {Bulky nanoporous oxide materials and manufacturing method of the same}

The present invention relates to a bulk oxide-based nanoporous porous body and a method for manufacturing the same, and more particularly, it is possible to implement a bulked oxide-based nanoporous porous body in the form of agglomerate rather than a powder form, the process is simple, high reproducibility, rapid The present invention relates to a method for producing a bulk oxide-based nanoporous porous body having high productivity, and capable of suppressing the growth of particles and sintering within a short time, and having high productivity, and a bulk oxide-based nanoporous porous body produced thereby.

In general, a material having a nanoporous structure arranged regularly or irregularly is defined as a nanoporous porous body. Among them, nanoporous materials in which fine pores are regularly arranged are divided into three according to the pore diameter (d) of the porous material according to the definition of the International Union of Pureand Applied Chemistry (IUPAC). The pore diameter is classified as microporous with 2 nm or less, mesoporous with 2-50 nm, and finally with macroporous with 50 nm or more.

The regularly ordered mesoporous material was first synthesized in 1990 by Yanagisawa's team with a pore diameter of 1.8 nm to 3.2 nm with surfactants as the template. Subsequently, M41S mesoporous material was synthesized by the researchers of Mobil, and according to the shape of the pores, MCM-41 for the hexagonal structure, MCM-48 for the cubic structure, and The lamellar structure was named MCM-50. These materials have uniform pores of nanometer size and have a large specific surface area. These properties lead to useful properties such as fluid permeability, filter effects, and the ability to block heat and sound. It can be used as a reaction catalyst for macromolecules by using low density and high surface area, and has been actively applied to electronic and optical base materials, hydrogen storage and energy materials, fine chemical materials, and medical materials. It has also been applied as a catalyst, adsorbent or carrier material. Thus, the porous body having nanopores is a material that is expected to be industrial and academic applications because there are many ranges that can be used, and also various applications.

Nanoporous porous bodies may be prepared by a polymer dispersion method, a sono-chemical method, or the like. In the case of the nano-porous porous body using such a manufacturing, the silica-based is most researched a lot, the silica-based because there is little electrical, magnetic and optical properties are subject to many industrial applications using it. Therefore, much interest and research on the synthesis and application of non-silica-based nanoporous porous bodies having electrical, magnetic and optical properties have been made.

Although non-silica TiO ₂ has been difficult to control the hydrolysis reaction, condensation reaction and oxidation / reduction of metal ions, many research results have been noted until recently. TiO ₂ is a semiconducting metal oxide, which is physicochemically very stable compared to other metal oxides of similar type, and has a suitable bandgap energy (3.2 eV), which is widely used in energy, environment, display, textile, and medical fields. . Nanoporous TiO ₂ powder is shown the superior physical properties owing to the arrangement and a large specific surface area of the regular pores compared with the nanoparticles TiO _2, whereby the photocatalyst, the dye-sensitized solar cells (DSSCs) electrode, in various fields such as the hydrogen electrode It is becoming an application.

On the other hand, the nano-porous porous body has been disadvantageous in that it is not easy to handle because it is manufactured in the form of powder or thin film in the manufacturing process, rather than being manufactured in bulk of a large mass. The bulking of nanoporous bodies has the advantage of broadening the utility of nanoporous structures in various fields such as energy and environment. Recently, a research team from A. Nakahira of Osaka Prefectural University has succeeded in producing silica and TiO ₂ nanoporous bulks using hydrothermal hot-pressing method. There is a disadvantage that additional processes such as sintering time and cleaning are required.

The problem to be solved by the present invention is to realize the bulk of the oxide-based nanoporous porous body in the form of agglomerate, not a powder form, the process is simple, high reproducibility, and rapid temperature increase, while suppressing the growth of particles The present invention provides a method for producing a bulk oxide-based nanoporous porous body having high productivity by sintering within a short time, and a bulk oxide-based nanoporous porous body produced thereby.

The present invention includes the steps of preparing an oxide-based nanoporous powder, filling the oxide-based nanoporous powder into a mold and setting it in a chamber of a discharge plasma sintering apparatus, vacuuming the inside of the chamber to reduce the pressure, and Applying a direct current pulse while pressing the nanoporous powder to increase the target sintering temperature lower than the melting temperature of the oxide nanoporous powder, and pressing the oxide nanoporous powder at the sintering temperature to press the oxide nanoparticle. It provides a method for producing a bulk oxide-based nanoporous porous body comprising the step of discharge plasma sintering the porous powder and cooling the temperature of the chamber to obtain a sintered body.

The oxide-based nanoporous powder may be formed of at least one oxide selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Al ₂ O ₃ , SnO ₂ , WO _3, and HfO ₂ .

The preparing of the oxide-based nanoporous powder includes adding and dissolving a block copolymer in a solvent, mixing an oxide precursor alkoxide in a solvent in which the block copolymer is dissolved, and adding the oxide precursor alkoxide. Adding an acid to the solvent to form a sol having a pH in the range of 0.5 to 3.0, drying the sol to gel, and heat treating the gelled product to form an oxide-based nanoporous powder. It may include forming a.

The solvent is a prophenol solution, the oxide precursor alkoxide is Ti-isopropoxide, the acid is hydrochloric acid (HCl), the heat treatment is carried out at a temperature of 300 to 500 ℃, the oxide-based nanoporous The powder may be made of TiO ₂ .

The pressure for pressurizing the oxide-based nanoporous powder is in the range of 30 to 100 MPa, and the inside of the chamber is decompressed in the range of 1.0 × 10 ^{−3 to} 1.0 × 10 ⁻² torr, and the DC pulse is applied in the range of 0.1 to 2000 A. desirable.

The sintering temperature is 200 to 1000 ℃, it is preferably maintained for 1 to 30 minutes at the sintering temperature is discharge plasma sintering of the oxide-based nanoporous powder is preferred.

In addition, the present invention is prepared by the above method, the nanopores are connected to each other to form a network structure or evenly distributed, the average diameter size of the nanopores is in the range of 2 to 100nm, porosity is in the range of 20 to 50% It provides a bulk oxide-based nanoporous porous body.

The specific surface area of the bulk oxide-based nanoporous porous body may range from 20 to 1000 m 2 / g.

The bulk oxide-based nanoporous porous body may be made of one or more oxides selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Al ₂ O ₃ , SnO ₂ , WO _3, and HfO ₂ . .

According to the present invention, it is possible to implement the bulking oxide-based nanoporous porous body in the form of agglomerate rather than the conventional powder form.

The method for producing a bulk oxide-based nanoporous porous body of the present invention is a simple process and high reproducibility.

In addition, since the discharge plasma sintering method is used, the present invention can rapidly increase the temperature, thereby suppressing the growth of the particles and sintering within a short time, thereby increasing the productivity.

In addition, the bulk oxide-based nanoporous porous body prepared by the present invention has an effect that can broaden the utility of the nanoporous structure in various fields such as energy, environment.

1 is a view schematically showing a discharge plasma sintering apparatus.
2 is a transmission electron microscope (TEM) photograph of nanoporous TiO ₂ powder.
3 is an electron diffraction pattern of the nanoporous TiO ₂ powder.
FIG. 4 is an N ₂ adsorption-desorption curve of nanoporous TiO ₂ powder, and the inset included in FIG. 3 is a pore size distribution calculated by a Barrett-Joyner-Halenda (BJH) pore size model. Indicates.
5 is a transmission electron micrograph of the bulk oxide-based nanoporous porous body formed by sintering plasma discharge.
FIG. 6 is a view showing optical photographs and X-ray diffraction patterns of sintering temperatures of the bulk oxide-based nanoporous porous body formed by sintering the nanoporous TiO ₂ powder in the powder state through discharge plasma sintering.
7 is an N ₂ adsorption-desorption curve of a bulk oxide-based nanoporous porous body prepared through discharge plasma sintering.
8 is a graph showing the pore size distribution calculated by the BJH model for the bulk oxide-based nanoporous porous body prepared by discharge plasma sintering.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, it should be understood that the following embodiments are provided so that those skilled in the art will be able to fully understand the present invention, and that various modifications may be made without departing from the scope of the present invention. It is not.

The present invention provides a method for producing a bulk oxide-based nanoporous porous body in which the pore structure is maintained by directly sintering an oxide-based nanoporous porous body prepared in a powder form using a discharge plasma sintering method. Hereinafter, the powder refers to particles having a size in the range of 1 nm to 1 mm), and the bulk refers to agglomerates having a size larger than that of the powder. Nano pore is a concept that includes microporous, mesoporous, and macroporous, and refers to pores having a diameter ranging from 1 nm to 1 μm. A material having a plurality of nanopores is used, and nanoporosity is used to mean that a plurality of nanopores are formed.

The method of manufacturing a bulk oxide-based nanoporous porous body according to a preferred embodiment of the present invention can be implemented by sintering at a time for a short time using a discharge plasma sintering apparatus.

According to a preferred embodiment of the present invention, there is provided a method of preparing a bulk oxide-based nanoporous porous body, comprising preparing an oxide-based nanoporous powder, filling the oxide-based nanoporous powder into a mold, and setting the chamber in a discharge plasma sintering apparatus. And vacuuming the inside of the chamber to reduce the pressure, and applying a direct current pulse while pressurizing the oxide-based nanoporous powder to raise it to a target sintering temperature lower than the melting temperature of the oxide-based nanoporous powder; Discharge plasma sintering the oxide-based nanoporous powder while pressing the oxide-based nanoporous powder at a temperature, and cooling the temperature of the chamber to obtain a sintered body.

The oxide-based nanoporous powder may be formed of at least one oxide selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Al ₂ O ₃ , SnO ₂ , WO _3, and HfO ₂ .

The preparing of the oxide-based nanoporous powder includes adding and dissolving a block copolymer in a solvent, mixing an oxide precursor alkoxide in a solvent in which the block copolymer is dissolved, and adding the oxide precursor alkoxide. Adding an acid to the solvent to form a sol having a pH in the range of 0.5 to 3.0, drying the sol to gel, and heat treating the gelled product to form an oxide-based nanoporous powder. It may include forming a.

The solvent is a prophenol solution, the oxide precursor alkoxide is Ti-isopropoxide, the acid is hydrochloric acid (HCl), the heat treatment is carried out at a temperature of 300 to 500 ℃, the oxide-based nanoporous The powder may be made of TiO ₂ .

The pressure for pressurizing the oxide-based nanoporous powder is in the range of 30 to 100 MPa, and the inside of the chamber is decompressed in the range of 1.0 × 10 ^{−3 to} 1.0 × 10 ⁻² torr, and the DC pulse is applied in the range of 0.1 to 2000 A. desirable.

The sintering temperature is 200 to 1000 ℃, it is preferably maintained for 1 to 30 minutes at the sintering temperature is discharge plasma sintering of the oxide-based nanoporous powder is preferred.

In addition, the present invention is the nano-pores are connected to each other to form a network structure or evenly distributed, the bulk diameter oxide nano-pores having an average diameter range of 2 to 100nm, porosity range of 20 to 50%. Present the porous body.

The specific surface area of the bulk oxide-based nanoporous porous body may range from 20 to 1000 m 2 / g.

The bulk oxide-based nanoporous porous body may be made of one or more oxides selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , Al ₂ O ₃ , SnO ₂ , WO _3, and HfO ₂ . .

Hereinafter, a method of manufacturing the oxide-based nanoporous powder will be described in detail.

Oxide-based nanoporous powder may be prepared by various methods such as sol-gel method, and among these, it is preferable to use a surfactant mediated sol-gel method described below. Surfactant Intervention The sol-gel method uses a surfactant having both hydrophilic and hydrophobic properties. The surfactant enables the synthesis of self-assembled structures in water and an organic solvent. And organic-inorganic composite phase.

As an example, a method of preparing titanium oxide (TiO ₂ ) consisting of nanoporous powders using a sol-gel intercalation method in a sol-gel method is provided.

The process for preparing nanoporous TiO ₂ powders with randomly arranged nanopores is made with three interactions.

The first is organic-organic interaction, which forms micelles or liquid crystals in the organic phase through the intercalation of surfactants, and the second is inorganic-inorganic. -inorganic interactions to hydrolyze and polymerize in inorganic precursors, and third is organic-inorganic interactions to inorganic phases through interactions in organic-inorganic phases. (inorganic phase) formation process. By these three interactions, nanoporous TiO ₂ powders are collectively formed.

In order to form TiO ₂ composed of nanoporous powder, the organic-organic interaction is controlled through a surfactant, and an appropriate pH change is required to control the interaction between inorganic and inorganic. In the case of organic-inorganic interactions, the molar ratio change between the surfactant and the precursor also plays an important role.

The surfactant-containing sol-gel method according to a preferred embodiment of the present invention uses block copolymers (surfactants) as a template based on the interaction and uses propphenol and hydrochloric acid.

After the block copolymer is added to the prophenol and reacted by adding an acid, the prophenol is slowly evaporated to form a nanoporous TiO ₂ powder through self-combination with the Ti precursor while the surfactant has a template structure. have. In more detail, the block copolymer is added to a solvent to dissolve it, the oxide precursor alkoxide is mixed in a solvent in which the block copolymer is dissolved, and then an acid is added to the solvent to which the oxide precursor alkoxide is added. To form a sol having a pH in the range of 0.5 to 3.0, and then, the sol may be dried to gel, and the gelled product may be heat treated to form an oxide-based nanoporous powder.

The oxide-based nanoporous powder thus prepared is sintered using a spark plasma sintering (SPS) method.

The discharge plasma sintering (SPS) method is a technique using plasma as a technique capable of synthesizing or sintering a desired material in a short time. In the discharge plasma sintering (SPS) method, the electrical energy of a pulse is directly injected into a gap between particles of a green compact, and high energy of a high-temperature plasma (discharge plasma) generated by a spark discharge in an instant is applied to thermal diffusion, action of an electric field, etc. It is an effective application process. The sintering temperature can be controlled from low temperature to 2000 ℃ or higher by the generated plasma, and can be sintered or sintered in a short time including temperature rising and holding time in the temperature range of 200 ~ 1000 ℃ lower than other sintering processes. to be. In addition, it is possible to rapidly increase the temperature, thereby suppressing the growth of particles, sintering is possible in a short time, and has an excellent feature of easily sintering even an sintered material.

A method of sintering the oxide-based nanoporous powder using the discharge plasma sintering (SPS) method will be described in more detail. 1 is a view schematically showing a discharge plasma sintering apparatus.

Referring to FIG. 1, an oxide-based nanoporous powder 120 is charged into a mold 110 provided in a chamber 100, and the pressure in the chamber 100 is reduced in pressure and pressurized in one axis with a punch 130. It is sintered by applying a direct current pulse current in the direction parallel to. Due to the increase in temperature due to the pressurization and high current application during sintering, a reaction occurs between the powders to obtain a bulk oxide-based nanoporous porous body.

While the mold 110 filled with the oxide-based nanoporous powder is set in the chamber 100 of the discharge plasma sintering apparatus, the DC pulse is gradually applied by using a pulsed DC generator 140 while pressing after depressurization. The discharge plasma is sintered. The reduced pressure is preferably about 1.0 × 10 ^{−3 to} 1.0 × 10 ⁻² torr. In order to remove the impurity gas present in the chamber 100 and to reduce the pressure, a rotary pump (not shown) is operated to evacuate to a vacuum state (for example, about 1.0 × 10 ^{−3 to} 1.0 × 10 ⁻² torr) to reduce the pressure. do. The DC pulse is preferably applied in the range of 0.1 to 2000A.

In the case of rapidly applying a current when applying a DC pulse, it is difficult to control the sintering temperature because it is difficult to control the temperature. It is preferable that the temperature increase rate is about 10 to 100 ° C./min, and when the temperature increase rate is higher than 100 ° C./min, it may be difficult to control the sintering temperature. There are disadvantages.

The mold 110 may be provided in the shape of a cylinder or a prismatic cylinder, and after the oxide-based nanoporous powder 120 is charged into the mold 110, uniaxial compression is performed using the punch 130. The mold 110 is preferably made of a graphite (graphite) material having a high hardness and a high melting point.

At this time, the pressure applied to the oxide-based nanoporous powder (the pressure compressed by the mold) is preferably about 30 to 100 MPa. When the pressurization pressure is less than 30 MPa, there are many voids between the powder particles, so that the bulk oxide system having a desired density It is difficult to obtain nanoporous porous body, and high current must be applied for sintering, which can lead to high temperature rise.If the pressurization pressure exceeds 100MPa, further effects cannot be expected. This can increase the cost of manufacturing equipment.

When the temperature rises to a target sintering temperature (eg, 200 to 1000 ° C., which is lower than the melting temperature of the oxide nanoporous powder), the oxide-based nanoporous powder is sintered for a predetermined time (eg, 1 to 30 minutes). . The sintering temperature is preferably about 200 ~ 1000 ℃ in consideration of the diffusion of particles, the necking (necking) between the particles, etc. If the sintering temperature is too high, mechanical properties may decrease due to excessive growth of the particles, If the sintering temperature is too low, it is preferable to sinter at the sintering temperature in the above range because the characteristics of the bulk oxide-based nanoporous porous body due to incomplete sintering may not be good. According to the sintering temperature, there is a difference in the microstructure, particle size, etc. of the bulk oxide-based nanoporous porous body, because when the sintering temperature is low, surface diffusion is dominant, but when the sintering temperature is high, lattice diffusion and grain boundary diffusion proceed. It is preferable that the sintering time is about 1 to 30 minutes, but when the sintering time is too long, energy consumption is large, so it is not economical and it is difficult to expect further sintering effect, and the size of the bulk oxide-based nanoporous porous particles If the sintering time is small, the characteristics of the bulk oxide-based nanoporous porous body may be poor due to incomplete sintering. Even during sintering, the pressure inside the chamber is preferably kept constant at a reduced pressure of about 1.0 × 10 ^{−3 to} 1.0 × 10 ⁻² torr. When sintering, the pressure applied to the oxide-based nanoporous powder is preferably maintained at about 30 to 100 MPa. If the pressurization pressure is too small, it is difficult to obtain a bulk oxide-based nanoporous porous body of a desired density and the pressurization pressure is too large. Cracking may occur in the bulk oxide-based nanoporous porous body after the sintering process is completed.

After the sintering process is performed, cooling is performed to unload the sintered body (bulk type oxide-based nanoporous porous body). It is desirable to keep the pressure inside the chamber and the pressure compressed by the mold constant during cooling.

Hereinafter, experimental examples according to the present invention are specifically presented, and the present invention is not limited to the following experimental examples.

First, the manufacturing method of the nanoporous TiO ₂ powder will be described as an example.

Block copolymers called F127 (Aldrich, USA) were used. Ti precursor alkoxide used Ti-isopropoxide (Ti-isopropoxide).

16.16 g of block copolymer was added to 104.2 g of a prophenol solution, which was sufficiently dissolved for about 1 hour, and 63.16 g of Ti-isopropoxide was added to a propphenol solution containing block copolymer. After mixing, 45.8 g of hydrochloric acid (HCl) was added to a propphenol solution to which Ti-isopropoxide was added to adjust the pH to about 1.0 to 2.0 to form a sol.

In order to prepare a nanoporous TiO ₂ in the powder state, the sol was gelled by drying for 72 hours at room temperature in a petri dish in an open state.

In order to evaporate and remove the solvent and surfactant contained in the gelled product, heat treatment was performed at about 120 ° C. for 1 hour, followed by heat treatment at about 350 ° C. for 3 hours to form nanoporous TiO ₂ powder. It was.

Powdered nanoporous TiO ₂ made by this process was used in the preparation process of the bulk oxide-based nanoporous porous body.

Hereinafter, a method of manufacturing the bulk oxide-based nanoporous porous body will be described in detail.

Among the various oxide-based nanoporous powders, nanoporous TiO ₂ powders were directly sintered at a time by discharge plasma sintering to produce a bulk oxide-based nanoporous porous body.

₂ shows that the nanoporous TiO ₂ powder used in the preparation of the bulk oxide-based nanoporous porous body has interparticle porosity.

Referring to FIG. 2, the size of the TiO ₂ unit particles forming inter-pores is about 6 nm.

It can be confirmed from the electron diffraction image of FIG. 3 that the crystal structure of the TiO ₂ unit particle is an anatase phase.

The pore diameter of the nanoporous TiO ₂ powder was 5.4 nm, and the specific surface area and pore volume were confirmed to be 162 m ² / g and 0.218 cm ³ / g through N ₂ adsorption-desorption analysis of FIG. 4.

Using the nanoporous TiO ₂ powder, a bulk oxide-based nanoporous porous body was produced by the discharge plasma sintering method, and a photo of the bulk oxide-based nanoporous porous body formed by sintering is shown in FIG. 5.

During the discharge plasma sintering, the sintering was carried out for 5 minutes while varying the temperature to 350, 400, 450, 500, 550, 600 ° C. at a pressure of 30 MPa, and the sintering was carried out in a vacuum atmosphere of about 10 ⁻³ torr.

An X-ray diffraction pattern of the sintered compact is shown in FIG. 6. In the case of the bulk nanoporous porous TiO ₂ , only the anatase single phase was present up to the sintering temperature of 550 ° C., and the rutile phase was weakly observed together with the anatase phase at the sintering temperature of 600 ° C.

As the sintering temperature increases, the size of unit particles forming interpores also increases, which is shown in FIG. 5. In the case of the bulk oxide-based nanoporous porous body sintered at 350 ° C., the size of the unit particles was about 6.0 nm, which was almost the same as that of the powder particles. However, in the bulk oxide-based nanoporous porous body sintered at 600 ° C., the size of unit particles forming intergranular pores was significantly increased to about 25 nm.

Analysis of the internal pore size, specific surface area, and pore volume of the bulk oxide-based nanoporous porous body with increasing sintering temperature was performed through N ₂ adsorption-desorption analysis, and the results are shown in FIGS. 7 and 8.

The N ₂ adsorption-desorption curve of FIG. 7 clearly shows that the nanopores exist inside the bulk oxide-based nanoporous porous body formed by sintering even after the high-pressure sintering process.

It can be seen from the pore distribution of FIG. 8 that the nanopores exist inside the bulk oxide-based nanoporous porous body.

Primary particle size, specific surface area, pore volume, porosity, and porosity within the bulk oxide-based nanoporous porous body by sintering temperature obtained by the N ₂ adsorption-desorption analysis Average pore diameters are summarized in Table 1 below.

Unit particle size (nm) Specific surface area
(M < 2 > / g) Pore volume
(Cm3 / g) Porosity
(%) Average pore size (nm) Nanoporous Powder 6.1 162 0.218 48 5.4 Bulk nanoporous porous body formed by sintering at 350 ℃ 6.0 132 0.186 44 5.7 Bulk nanoporous porous body formed by sintering at 400 ℃ 9.3 104 0.165 41 6.2 Bulk nanoporous porous body formed by sintering at 450 ℃ 13.0 89 0.169 42 7.6 Bulk nanoporous porous body formed by sintering at 500 ℃ 14.8 64 0.146 38 9.0 Bulk nanoporous porous body formed by sintering at 550 ℃ 20.0 33 0.102 30 12.4 Bulk nanoporous porous body formed by sintering at 600 ℃ 25.0 29 0.110 31 14.9

As described above, the present invention confirmed that the preparation of the bulk oxide-based nanoporous porous body was possible.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, This is possible.

Description of the Related Art
100: chamber 110: mold
120: Powder 130: Punch
140: DC pulse oscillator

Claims (9)

Adding a block copolymer to a solvent to dissolve it;
Mixing an oxide precursor alkoxide in a solvent in which the block copolymer is dissolved;
Adding an acid to the solvent to which the oxide precursor alkoxide is added to form a sol having a pH in the range of 0.5 to 3.0;
Drying the sol to gelate the sol; And
Heat-treating the gelled product to form an oxide-based nanoporous powder having nanopores;
Filling said oxide-based nanoporous powder with nanopores into a mold and setting it in a chamber of a discharge plasma sintering apparatus;
Vacuuming the inside of the chamber to reduce the pressure, and applying a direct current pulse while pressurizing the oxide-based nanoporous powder having nanopores to raise the target sintering temperature lower than the melting temperature of the oxide-based nanoporous powder having nanopores. step;
Discharge plasma sintering the oxide-based nanoporous powder having nanopores while pressing the oxide-based nanoporous powder having nanopores at the sintering temperature; And
Cooling the temperature of the chamber to obtain a sintered body,
The oxide-based nanoporous powder having nanopores is composed of one or more oxides selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , SnO ₂ , WO _3, and HfO ₂ ,
The sintered body is a nano-pores connected to each other to form a network structure or evenly distributed, the average diameter of the nano-pores is in the range of 2 to 100nm, the porosity is characterized in that the bulk oxide type range of 20 to 50% Method of manufacturing nanoporous porous body.
delete delete The method of claim 1, wherein the solvent is a prophenol solution, the acid (acid) is hydrochloric acid (HCl), the heat-treatment is characterized in that the bulk oxide-based nanoporous porous body is carried out at a temperature of 300 ~ 500 ℃. Way.
According to claim 1, wherein the pressure for pressing the oxide-based nanoporous powder is in the range of 30 ~ 100MPa, the inside of the chamber is decompressed in the range of 1.0 × 10 ^-3 ~ 1.0 × 10 ^-2 torr, the DC pulse is 0.1 ~ Method for producing a bulk oxide-based nanoporous porous body characterized in that applied to the range 2000A.
The method of claim 1, wherein the sintering temperature is 200 to 1000 ℃, the bulk oxide-based nano-porous porous body characterized in that the discharge plasma sintering of the oxide-based nanoporous powder is maintained at 1 to 30 minutes at the sintering temperature Manufacturing method.
Prepared by the method of claim 1, the nanopores are connected to each other to form a network structure or evenly distributed, the average diameter size of the nanopores is in the range of 2 to 100nm, the porosity is in the range of 20 to 50% Bulk oxide-based nanoporous porous body.
The bulk oxide-based nanoporous porous body according to claim 7, wherein the specific surface area of the bulk oxide-based nanoporous porous body is in a range of 20 to 1000 m 2 / g.
The method of claim 7, wherein the bulk oxide-based nanoporous porous body is composed of one or more oxides selected from TiO ₂ , SiO ₂ , ZrO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , SnO ₂ , WO ₃ and HfO ₂ . A bulk oxide-based nanoporous porous body, characterized in that.

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