KR20130032190A - Composite powders having core-shell structure and methods for fabricating the same - Google Patents

Abstract

PURPOSE: Core-shell structure composite powder is provided to improve connection between pores and particles and to improve the physical property of a fuel electrode or a functional layer. CONSTITUTION: A manufacturing method of core-shell structure composite powder(3) comprises a step of manufacturing a slurry mixture by dispersing core powder in an aqueous solution or organic solvent which comprises one or more metal precursors, and activating the surface thereof; a step of synthesizing the core-shell structure composite powder by mixing and stirring subcritical or supercritical fluid into the slurry mixture; and a step of removing the fluid and a reaction solution to separate the composite powder. The subcritical or supercritical state is at 30-400>= and 0.5-50MPa. The synthetic reaction is carried out for 1minutes-100hours.

Description

Composite powder of core-cell structure and its manufacturing method {COMPOSITE POWDERS HAVING CORE-SHELL STRUCTURE AND METHODS FOR FABRICATING THE SAME}

The present invention relates to a composite powder having a core-cell structure applicable to a fuel electrode of a fuel cell, a functional layer of the fuel electrode, or a catalyst for a reformer for syngas and hydrogen production, and a method of manufacturing the same. The present invention relates to a core-cell composite powder in which a nano nickel oxide layer or a nano nickel layer is formed on a core particle surface of zirconia or doping ceria. The invention also relates to a method of using such a composite powder.

As an example of the present invention, for an oxide fuel cell, the unit cell structure includes an oxygen ion conductive electrolyte, a cathode and an anode disposed on both sides thereof. The working principle is that oxygen ions produced by the reduction reaction of oxygen at the cathode move to the anode through the electrolyte and react with hydrogen supplied to the anode again to generate water. When the two poles are connected, electrons are generated at the anode. In the air electrode, electrons are consumed to generate electricity.

A functional layer may be interposed between these layers and the electrolyte layer to promote the electrical reaction in the air electrode or the fuel electrode. These anodes or functional layers are composed of ceramic-metal (Cermat) composites such as Ni-YSZ (Yttria stabilized zirconia) or Ni-GDC, and these materials have a porous structure with a complex structure consisting of a continuous network. It is necessary to have a pore structure in order to create a fuel electrode having high catalyst properties, long-term stability, redox stability and mechanical properties.

According to the conventional method, the nickel oxide powder and the YSZ powder are mixed, molded and fired to form a sintered body, and then heat-treated in a reducing atmosphere to prepare a Ni-YSZ composite. For example, US Patent Publication Nos. 2007/0077476 and 2001/0220721 disclose a method of mixing different raw material powders by a physical wet process in order to make the composite powder of the anode or the functional layer uniformly mixed. This is described. When different anode material powders are mixed and dried in this manner to obtain a composite powder, the anode prepared from such powders has a performance depending on normal percolation.

Although it is advantageous to manufacture by the physical mixing method, the process is simple, but uniform dispersion and mixing do not occur after mixing and drying due to the difference in cohesion, specific gravity, and size between two phases of NiO and YSZ. It is formed to form a fuel electrode or a functional layer having a non-uniform microstructure.

The non-uniform structure caused by the shape, size, cohesion, etc. of the raw material powders lowers the connection between pores and particles, generates coarse aggregates, and the like, such as electrical conductivity, gas permeability, and activity of three-phase interface. It will adversely affect the physical properties. In the case of the anode support, when the anode having such a non-uniform structure is formed, the pinhole and the interfacial strength of the solid electrolyte layer are greatly influenced, thereby greatly reducing the durability, mechanical properties, and output characteristics of the unit cell.

In particular, long-term operation of such a non-uniform structure leads to coarsening and densification of nickel metal, which causes defects such as cracking of electrolytes when repeated volume changes due to thermal cycling and redox reactions occur. Due to the reduction of the three-phase interface consisting of YSZ and pores, the electrochemical activity is decreased and the active polarization resistance is increased, causing the output of the unit cell to be lowered.

In addition, hydrogen used to drive fuel cells is produced by a gas to liquid (GTL) process, that is, a dry reforming reaction and a steam reforming reaction, which is expensive to convert natural raw gas into synthetic gas. Instead of noble metal catalysts, mainly inexpensive Ni catalysts are used industrially. In the reforming reaction of methane, both the dry reforming reaction using carbon dioxide as the oxidant and the steam reforming reaction using distilled water as the oxidant have enthalpies of 248 and 206 kJ / mol, respectively, and require a lot of energy in hydrogen production. For this reason, some of the oxygen is used during the reaction to cause an autothermal reforming (ATR) reaction, which causes local hot spots to cause extremely low synthesis gas productivity.

Patent Document 1: United States Patent Application Publication No. 2007/0077476 Patent Document 2: United States Patent Application Publication No. 2001/0220721

As described above, in order to reduce or eliminate the uneven microstructure of a fuel electrode, a functional layer, or a catalyst which causes degradation of a unit cell and catalyst characteristics such as a decrease in strength and three-phase interface, a decrease in output, and local heating, etc. There is a limit to the method of physical mixing, and a method of making a composite powder of a more fundamental solution is required.

Although many physical and chemical attempts have been made to achieve this, a method of economically enabling scale-up as well as obtaining uniformity of mixing without agglomeration between particles during drying remains a problem to be solved.

In order to solve this problem, the present invention aims to produce a composite powder of a core-cell structure having a uniformity from a mixture of raw materials.

Another object of the present invention is to control porosity, pore size and distribution in producing a sintered compact using composite powder, and to reduce or eliminate coarse particles due to abnormal grain growth of aggregates and cell particles.

Still another object of the present invention is to improve the mechanical, electrical and thermal properties of the anode, functional layer or catalyst produced using the composite powder.

Summary of the Invention The present invention for achieving the above object is as follows.

Method for producing a composite powder of the core-cell structure according to the present invention comprises the steps of dispersing or surface-activated the core powder in an aqueous solution or an organic solvent containing at least one metal precursor to prepare a mixed slurry, and And mixing the fluid in a subcritical or supercritical state to proceed with the synthesis reaction of the composite powder of the core-metal compound structure, and separating the composite powder by removing the fluid and the reaction product solution.

In a preferred embodiment, the supercritical or subcritical state may be at a temperature of 30 to 400 ° C. and a pressure condition of 0.5 to 50 MPa, and the synthesis reaction may proceed for 1 minute to 100 hours.

In a preferred embodiment, the organic solvent is C ₁ To C ₁₀ alcohols may include one or more.

In a preferred embodiment, by using two or more metal precursors in the step of preparing a slurry, a composite powder finally containing a metal compound of a composite or a substituted solid solution can be obtained.

In a preferred embodiment, in the step of preparing the slurry, an aqueous or organic solvent in which the core powder and the at least one metal precursor are mixed is ultrasonically or mechanically milled to form a dispersed or activated solution, and the carbon dioxide fluid in a supercritical state is added to the solution. It is possible to obtain a uniform mixed fluid by stirring while diffusing and dissolving.

In a preferred embodiment, the subcritical or supercritical fluid may be a mixed fluid of at least two kinds selected from water, ethanol, organic solvent and carbon dioxide.

In a preferred embodiment, after the step of preparing the slurry, acid or alkali is added and water, organic solution, or supercritical water for 1 minute to 10 hours at a temperature of 30 to 100 ° C. and a pressure of 0.5 to 15 MPa, or Can be reacted in a mixed fluid of carbon dioxide.

In a preferred embodiment, the metal precursor may be a fluoride salt, a chloride salt, an inorganic acid salt or an organic acid salt of metal, or a metal hydrate or metal complex.

In a preferred embodiment, the metal precursor is Ru, Rh, Cu, Ag, Au, Pd, Pt, Sb, Sc, Sr, V, Cu, Y, Ce, Mo, W, Fe, Zr, Co, Ni, Zn, Cd, Mn, Ca, Ba, Cs, Cr, Mg, Ti, Al, In, Sn, Se, Fe, Cd, Te, Ga, Gd, Ge, Dy, Pr, Sm, Ho, Lu, Tb, It may comprise one or more components selected from the group consisting of Eu, Nd, La, Ta, Hf, Er and Yb.

In a more preferred embodiment, the core powder may comprise zirconia or ceria.

In a preferred embodiment, at least one metal precursor may be dispersed at 0.01 to 5 mol / L in the organic solvent in the step of preparing the mixed slurry.

In a preferred embodiment, the organic solvent can be methanol or ethanol.

In a preferred embodiment, the organic solvent may further comprise 0.01 to 10 moles of secondary or tertiary alcohols as cosolvents relative to 1 mole of the metal precursor.

In a preferred embodiment, before or during the synthesis reaction, 0.01 to 20 moles of basic or acidic solution relative to 1 mole of the metal precursor is added, or 0.01 to 10 moles of reducing or oxidizing agent relative to 1 mole of metal additive precursor and At least one selected from the group consisting of aromatic hydrocarbons can be added.

In a preferred embodiment, ammonia, nitrogen, methane, helium or argon gas may be further added before or during the step of proceeding with the synthesis reaction.

The method of using the composite powder prepared according to the present invention, the composite powder is used in the field of catalyst material, desulfurization material or fuel cell electrode material of fuel or fuel cell, granule, ball, disk, cylinder, honeycomb, Processing into any one of a sheet and a composite film, or coating on any one of ceramics, metal, polymer film, substrate and support.

In the composite powder produced according to the present invention, metal compound particles are formed around the core powder to have a core-cell structure.

In a more specific embodiment of the present invention, a composite powder having a core-cell structure is obtained by reacting a zirconia or ceria core particle with a nickel salt in a supercritical carbon dioxide-ethanol cosolvent in the preparation of a mixture powder of an anode, a functional layer, and a catalyst. In addition, in the present invention, not only forms a strong bond between the surface of the core particle and the nickel reaction product by surface activation, but also lowers the surface tension of the reaction fluid by a carbon dioxide cosolvent, thereby reducing the cohesiveness after the reaction and drying, so that uniform mixing is achieved. The present invention also proposes a composite powder having greatly improved dispersibility and a fuel electrode, a functional layer, or a catalyst structure obtained therefrom.

The composite powder of the core-cell structure constituting the anode or the functional layer not only greatly increases the three-phase interface by forming a porous nickel oxide layer of nanostructure on the core particle surface, but also causes unevenness caused by conventional physical mixing. By making the microstructure more uniform, the connection between pores and particles is increased, and coarse aggregates are eliminated to improve the properties of the anode or functional layer such as electrical conductivity, gas permeability, and activity of three-phase interface. In particular, the uniform microstructure of the anode in the anode support fuel cell may increase the durability, mechanical properties, and output characteristics of the unit cell by improving defects and interfacial strength of the electrolyte layer. In addition, it has the effect of suppressing coarsening and densification of nickel particles during long-term operation so that defects such as cracking of electrolyte due to thermal cycles do not occur, and the three-phase interface composed of Ni, YSZ and pores does not decrease, and thus electric There is no reduction in chemical activity so that the output of the cell can be maintained without deterioration.

In addition, the heat dissipating catalyst structure made from powder made of core-cell structure of nickel metal having high thermal conductivity in oxide core particles having low thermal conductivity can greatly increase the thermal diffusion effect and prevent local heat rise by combustion reaction. It makes the gas more reactive. In particular, the thermal conductivity of the reaction catalyst can be increased, so that the temperature distribution in the reformer reactor can be made uniform.

1 is a schematic diagram of a core powder, a cell powder, and a core-cell powder.
Figure 2 is a zirconia core powder electron micrograph.
3 is an electron micrograph of zirconia-nickel oxide (30%) core-cell powder.
4 is an electron micrograph of zirconia-nickel oxide (50%) core-cell powder.
5 is an XRD pattern of zirconia-nickel oxide core-cell powder.
6 is an XRD pattern of zirconia-nickel core-cell powder after reduction.
7 shows the specific surface area of zirconia-nickel oxide core-cell powders.
8 is an EPMA elemental analysis spectrum of a zirconia-nickel oxide (30%) powder composite.
9 EPMA mapping of zirconia-nickel oxide (30%) powder composite.
10 is a cross-sectional electron micrograph of a composite composed of an electrolyte / functional layer / fuel electrode.

Hereinafter, the present invention will be described in more detail. The following embodiments are presented by way of example only so that the present invention can be easily understood, and the present invention is not limited to such embodiments.

According to one embodiment of the manufacturing method of the present invention, by ultrasonically or mechanically milling a mixed solution containing a core powder such as dope zirconia or doping ceria powder in a solution in which one or more metal precursors are dissolved in distilled water or an organic solvent as an additive. And dispersing or activating the obtained slurry or activated slurry solution with a carbon dioxide fluid in a supercritical state while stirring to obtain a uniform mixed fluid before the reaction.

The organic solvent used in the present invention preferably contains at least one C ₁ -C ₁₀ alcohol, more preferably methanol, isopropyl alcohol or ethanol.

At this time, if necessary, 0.01 to 10 moles of secondary or tertiary alcohols relative to 1 mole of the metal precursor can be used as a cosolvent. When the cosolvent is added, it is easy to adjust the concentration of the metal complex salt in some cases, increase the yield of the metal compound, high replacement capacity, and control the particle size and shape of the metal compound produced in various ways. The resulting metal compound particles may have the shape of spheres, fibers, sheets, wires, bundles, cubics, or pyramidals.

The metal precursor that can be used in the present invention is not particularly limited. Preferably, metal fluoride salts, chloride salts, inorganic acid salts such as nitrate salts, sulfate salts, carbonate salts, organic acid salts such as acetates, and the like, or metal hydrates, metal complexes and the like can be used. In particular, metal nitrates, metal organic salts or metal chlorides are most preferred.

Ni is mainly used as a metal component of the fuel electrode, the functional layer, or the metal precursor constituting the catalyst formed on the core particles, but it activates the reaction in the three-phase interface, or activates the catalytic activity, the stability of the oxidation-reduction reaction, As additives for imparting resistance, Ru, Rh, Cu, Ag, Au, Pd, Pt, Sb, Sc, Sr, V, Cu, Y, Ce, Mo, W, Fe, Zr, Co, Zn, Cd, Mn, Ca, Ba, Cs, Cr, Mg, Ti, Al, In, Sn, Se, Fe, Te, Ga, Gd, Ge, Dy, Pr, Sm, Ho, Lu, Tb, Eu, Nd, La, It may comprise one or more components selected from the group consisting of Ta, Hf, Er and Yb.

In this step, the concentration of the metal precursor in the organic solvent can be adjusted differently according to the purpose of use, but preferably 0.0001 to 5 mol / L, more preferably 0.001 to 0.5 mol / L. The economical efficiency and finer particles can be produced and the yield can be further increased than the above range.

As the metal precursor used in the present invention, two or more kinds of metal precursors may be mixed and used, and as a result, a fine powder of a core-cell structure coated with a metal compound of a composite or a substituted solid solution through a synthetic reaction and a heat treatment process as necessary. Can be obtained. When two or more kinds of metal precursors are mixed, various metal precursor components may be combined depending on the application field and the method of use of the metal compound powder. The mixing ratio should also be adjusted so that the amount of each metal ion present in the metal precursor solution corresponds to the stoichiometric ratio required to obtain the final synthetic powder.

If necessary, the carbon dioxide fluid used in the present invention may be prepared by maintaining the carbon dioxide at a temperature of 30 to 100 ℃ and pressure conditions of 0.5 to 30 MPa.

If desired, the initial first step of the process according to the invention is a subcritical or supercritical state after mixing and dispersing the core powder solution in an organic solvent in which one or more metal precursors are dissolved, adding an acid or an alkali It can be carried out by obtaining a mixed fluid by aging and surface activity for 1 minute to 10 hours at a temperature of 30 to 100 ℃ and a pressure of 0.5 to 15 MPa while mixing with a carbon dioxide fluid of May be omitted.

According to the preparation method of the present invention, as a second step, the mixed fluid obtained in the first step is synthesized while flowing in a subcritical or supercritical state at a pressure of 5 to 50 MPa while raising the temperature to 30 to 400 ° C. Or synthesized by holding in the chamber for 1 minute to 100 hours.

In this step, the reaction temperature is preferably 30 to 400 ℃, especially 350 to 400 ℃ under supercritical water, the reaction pressure is preferably maintained at 25 to 50 MPa, the reaction temperature is 50 under supercritical carbon dioxide mixed fluid It is preferably from 250 to 250 ° C., and the pressure is maintained at 5 to 30 MPa, and the reaction time is preferably several seconds to 100 hours, particularly 1 minute to 20 hours. In the above preferred range, the reaction can be further accelerated, the resulting particle size is evenly made, the particle shape can be controlled more easily, the crystallinity can be further increased, and the device and energy costs can be further reduced.

In this step, an acidic solution such as alkali or sulfuric acid, such as 0.01 to 20 moles of ammonia, relative to 1 mole of the metal precursor, may be added before or during the reaction, and also reduced to 0.01 to 10 moles of hydrogen, such as 1 mole of the metal precursor. At least one of an oxidizing agent such as a zener, oxygen, hydrogen peroxide, and aromatic hydrocarbon can be added before or during the reaction. Introduction of such an alkaline solution, acidic solution, reducing or oxidizing agent, aromatic hydrocarbon, etc., may help to control the substitutional high capacity of the resulting metal compound powder, depending on the amount and method of addition, I can regulate it.

In addition, if necessary, a reactive or carrier gas such as ammonia, nitrogen, methane, helium, argon, or the like may be added before or during the reaction, which promotes or inhibits the reaction with the metal precursor, thereby reducing the size and It can help you control its appearance.

According to the preparation method of the present invention, the reactant obtained in the second step is cooled and dried to separate the resulting core-cell powder. If desired, the drying process is preferably carried out supercritical drying of the cooled reactant at a temperature of 30 to 100 ℃ and a pressure of 3 to 20 MPa.

In order to further increase the crystallinity of the reactants obtained according to the above method or to obtain various types of phases through pyrolysis, various kinds of reaction furnaces or microwave synthesis furnaces may be further heat-treated under vacuum, atmospheric pressure or pressure conditions. .

The metal reactant of the present invention is obtained in powder form, but may be provided in various materials by arbitrarily modifying the form. For example, the fine powder of the core-cell structure in which the metal compound of the present invention is formed may be used in the field of catalyst material, desulfurization material, or fuel cell electrode material of fuel or fuel cell, and may be used in paste, granule, pellet, and ball. It may be further processed into a disc, tube, honeycomb, sheet, or composite film, or coated on a film, substrate, or support of ceramics, metals, polymers.

Hereinafter, the present invention will be described in detail with reference to Examples, but the scope of the present invention is not limited to the following Examples.

≪ Example 1 >

Example 1 is an example of preparing a stabilized zirconia-nickel compound composite powder according to the method of the present invention, the preparation method thereof is described in detail below.

Nickel nitrate was added to ethanol at a concentration of 0.1 mol / L, followed by well stirring and dispersion to obtain a metal salt solution. 200 grams of zirconia (8% YSZ) powder was taken, and the nitrate solution was mixed and stirred so that the mass ratio of nickel oxide to zirconia was 5% in a slurry dispersed in ethanol, and the temperature was raised to 30 ° C. At the same time, after injecting carbon dioxide using a 1/4 inch (0.64 cm) inner tube, the pressure in the reactor was maintained at 5 MPa so that the carbon dioxide became subcritical to obtain a mixed fluid in which carbon dioxide fluid was mixed into the metal salt solution. Thereafter, the temperature of the mixed fluid was raised to a reaction temperature of 80 to 200 ° C., and the pressure was adjusted to 10 MPa to make a supercritical state, and then reacted for 1 hour and then cooled. Thereafter, the reaction product was supercritical dried to separate carbon dioxide and the filtrate to obtain a reaction product powder. These powders were shaped into plates, disks, or pellets, and then reduced in an hydrogen atmosphere at 800 ° C. for 1 hour to obtain a Ni-YSZ composite.

<Example 2>

The Ni-YSZ composite was obtained by performing the same conditions as in Example 1, but adjusting the composition ratio so that the weight ratio of nickel oxide to zirconia was 10%.

<Example 3>

The Ni-YSZ composite was obtained by performing the same conditions as in Example 1, but adjusting the composition ratio so that the weight ratio of nickel oxide to zirconia was 30%.

<Example 4>

The Ni-YSZ composite was obtained by carrying out the same conditions as in Example 1, but adjusting the composition so that the weight ratio of nickel oxide to zirconia was 50%.

<Example 5>

A porous Ni-YSZ composite sintered compact was obtained from the powder prepared by carrying out the same conditions as in Example 1, but adjusting the composition ratio to make the weight ratio of nickel oxide to zirconia 30%.

<Characteristics of Powder and Sintered Body According to Examples 1 to 5>

FIG. 1 is a schematic diagram showing a process in which cell particles 2 are formed on core particles 1. Reference numeral 3 in FIG. 1 denotes a core-cell composite powder. 2 to 4 are electron microscope images of the metal oxide composite powders obtained in Examples 1 to 4, and FIG. 2 is a photograph of the yttria stabilized zirconia core powder, and FIGS. 3 and 4 are nickel oxide contents. Shows electron micrographs of the core-cell particles obtained by adjusting the component ratio of the metal salt to 30 and 50% by weight. It can be observed that NiO particles of 30 nm or less are well formed on the zirconia powder of about 100 nm.

The components of the metal oxide composite powders obtained in Examples 1 to 4 were analyzed by EDX (Energy Dispersive X-ray) of electron microscope, and summarized in Table 1 below.

Element Example 1 Example 2 Example 3 Example 4 O K 75.57 72.40 66.23 65.26 Ni K 1.95 4.12 11.14 15.61 Y L 3.36 3.64 3.29 3.05 Zr L 19.12 19.84 19.34 16.08 Totals 100 100 100 100

Component analysis results by EDX of zirconia-nickel oxide powder according to Examples 1 to 4 (unit: at%)

As the addition amount of the metal salt was increased so that the nickel oxide content was changed from 5 to 50%, the content of Ni metal in the synthesized core-cell powder was greatly increased, indicating that cell formation was successful.

5 shows that XRD analysis of the zirconia-nickel oxide core-cell powder obtained by heat treatment after synthesis according to Examples 1 to 3 shows that NiO crystal phase is well developed as the content of NiO increases.

FIG. 6 shows that Ni metal was formed as a result of XRD analysis of the zirconia-nickel core-cell powder obtained after reducing the powder of Example 3.

7 is a view showing the change in specific surface area of the zirconia core powder and the zirconia-nickel oxide core-cell powder prepared according to the above embodiment, the specific surface area of the core powder alone from 16 m ² / g to about 28 m ² / It can be seen that the content of nickel oxide cells in the resulting core-cell powder is increased by increasing to g.

8 and 9 are photographs showing EPMA component analysis spectra and component mapping results of composites prepared from zirconia-nickel oxide core-cells according to Example 3, showing that the nickel elements are very uniformly distributed throughout. Is showing.

The physical properties of the metal oxide composite powders obtained in Examples 1 to 4 above were summarized in Table 2 below. From the results of Table 2, it can be seen that the specific surface area increases with the increase of the Ni content, and the thermal conductivity is 0.1 to 0.35 as the Ni content increases in the Ni-YSZ powder reduced from the NiO-YSZ composite powder. From the tendency to increase to W / mK, it can be seen that the heat transfer characteristics of the composite powder are high due to the high thermal conductivity of the Ni cell. This indicates that the powder obtained from the above examples can effectively release the heat of local hot spots that can occur during the exothermic reaction of the ATR (autothermal reformer) catalyst.

Kinds NiO content in powder (%) Specific surface area before reduction
(m ² / g) Thermal conductivity after reduction (W / mK) Pure zirconia powder 0 16 0.1 NiO-YSZ composite powder according to Example 1 5 18 0.13 NiO-YSZ composite powder according to Example 2 10 19 0.18 NiO-YSZ composite powder according to Example 3 30 25 0.28 NiO-YSZ composite powder according to Example 4 50 28 0.35

Measurement results of physical properties of zirconia-nickel oxide powders according to Examples 1 to 4

FIG. 10 shows a cross-sectional structure of a composite sintered body including a functional layer 5 made from zirconia-nickel oxide powder prepared according to Example 3, and it can be seen that a highly uniform porous functional layer is formed. In FIG. 10, 4 and 6 are electrolyte and an anode, respectively.

The porous nano-ceramic-metal composite powder obtained from the preparation of the present invention may be further processed into a paste, granule, ball, disc, tube, honeycomb, sheet, or composite film, or coated on a film, substrate, or support of ceramics, metal, or polymer. After the sintering is carried out and reduced to produce a sintered compact including a fuel electrode or a functional layer or a multi-layer composite sintered compact, it can be used in the field of fuel material, functional layer or reforming catalyst of natural gas.

1: core particle
2: cell particles
3: core-cell composite powder
4: electrolyte
5: functional layer
6: anode

Claims (22)

In the method for producing a composite powder of the core-cell structure,
Preparing a mixed slurry by dispersing and surface-activating the core powder in an aqueous solution or an organic solvent including at least one metal precursor;
Advancing the reaction of the composite powder of a core-metal compound structure by stirring while mixing a fluid in a subcritical or supercritical state with the mixed slurry;
Separating the complex powder by removing the fluid and the reaction product solution
Composite powder production method comprising a. The method of claim 1,
The supercritical or subcritical state is a state of a temperature of 30 to 400 ℃ and a pressure condition of 0.5 to 50 MPa, the synthesis reaction, characterized in that for 1 minute to 100 hours. The method according to claim 1 or 2,
The organic solvent is a method for producing a composite powder, characterized in that it comprises at least _one of C ₁ to C ₁₀ alcohol. The method according to claim 1 or 2,
By using two or more metal precursors in the step of preparing a slurry,
Finally, a composite powder production method comprising a composite powder containing a metal compound of a composite or substituted solid solution. The method according to claim 1 or 2,
In the step of preparing a slurry, an aqueous or organic solvent mixed with a core powder and one or more metal precursors is ultrasonically or mechanically milled to form a dispersed or activated solution,
A method for producing a composite powder, characterized in that a uniform mixed fluid is obtained by stirring while diffusing and dissolving a carbon dioxide fluid in a supercritical state. The method according to claim 1 or 2,
The fluid of the subcritical or supercritical state is a composite powder production method characterized in that the mixed fluid of at least two kinds selected from water, organic solvent and carbon dioxide. The method according to claim 1 or 2,
The metal compound produced during the synthesis reaction may have at least one shape among spheres, fibers, sheets, wires, bundles, cubics, and pyramidals. The composite powder manufacturing method characterized by the above-mentioned. The method according to claim 1 or 2,
After the step of separating the composite powder composite powder manufacturing method characterized in that for further reduction heat treatment. The method according to claim 1 or 2,
After the step of preparing the slurry, acid or alkali is added,
Method for producing a composite powder, characterized in that the reaction in a supercritical water, organic solution, or a mixed fluid of carbon dioxide for 1 minute to 10 hours at a temperature of 30 to 100 ℃ and a pressure of 0.5 to 15 MPa. The method according to claim 1 or 2,
The metal precursor is a fluorine salt, chloride, inorganic acid salt or organic acid salt of the metal, composite powder manufacturing method, characterized in that the metal hydrate or metal complex. The method according to claim 1 or 2,
The metal precursor is Ru, Rh, Cu, Ag, Au, Pd, Pt, Sb, Sc, Sr, V, Cu, Y, Ce, Mo, W, Fe, Zr, Co, Ni, Zn, Cd, Mn , Ca, Ba, Cs, Cr, Mg, Ti, Al, In, Sn, Se, Fe, Cd, Te, Ga, Gd, Ge, Dy, Pr, Sm, Ho, Lu, Tb, Eu, Nd, La Method for producing a composite powder, characterized in that it comprises at least one component selected from the group consisting of Ta, Hf, Er and Yb. The method according to claim 1 or 2,
The core powder comprises zirconia or ceria. The method according to claim 1 or 2,
Method for producing a composite powder, characterized in that at least one metal precursor is dispersed in an organic solvent at 0.01 to 5 mol / L in the step of preparing a mixed slurry. The method according to claim 1 or 2,
The organic solvent is a composite powder production method, characterized in that methanol or ethanol. The method of claim 13,
The organic solvent, the method of producing a composite powder, characterized in that it further comprises 0.01 to 10 moles of secondary or tertiary alcohols as a cosolvent relative to 1 mole of the metal precursor. The method according to claim 1 or 2,
Before or during the synthesis reaction, 0.01 to 20 moles of basic or acidic solution relative to 1 mole of the metal precursor is added, or 0.01 to 10 moles of reducing agent or oxidizing agent and aromatic hydrocarbon to 1 mole of metal additive precursor. Method for producing a composite powder, characterized in that at least one selected from. The method according to claim 1 or 2,
A method for producing a composite powder, characterized by further adding ammonia, nitrogen, methane, helium or argon gas before or during the step of proceeding with the synthesis reaction. A method of using the composite powder prepared according to claim 1 or 2, wherein the composite powder is used in the field of catalyst material, desulfurization material or fuel cell electrode material of a fuel or fuel cell. , Cylinder, honeycomb, sheet, and composite film processing, or a method of using a composite powder comprising the step of coating on any one of a film, a substrate and a support of ceramics, metal, polymer. A composite powder prepared according to claim 1 or 2,
A composite powder, wherein the metal compound particles are formed around the core powder to have a core-cell structure. 20. The method of claim 19,
Metal compound particles are composite, characterized in that it has one or more shapes of spheres, fibers, sheets, wires, bundles, cubic and pyramidal powder. 20. The method of claim 19,
The metal compound is Ru, Rh, Cu, Ag, Au, Pd, Pt, Sb, Sc, Sr, V, Cu, Y, Ce, Mo, W, Fe, Zr, Co, Ni, Zn, Cd, Mn , Ca, Ba, Cs, Cr, Mg, Ti, Al, In, Sn, Se, Fe, Cd, Te, Ga, Gd, Ge, Dy, Pr, Sm, Ho, Lu, Tb, Eu, Nd, La Composite powder, characterized in that it comprises at least one component selected from the group consisting of Ta, Hf, Er and Yb. 20. The method of claim 19,
The core powder is a composite powder, characterized in that it comprises zirconia or ceria.

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