KR20180062080A - MXENE/SiC/FERRITE COMPOSITE AND PREPARATION THEREOF - Google Patents

Abstract

Provided is a MXene/silicon carbide/ferrite composite attached to MXene of chemical formula 1, M_(n+1)X_n, and interlayers or surface of the MXene and containing ferrite of chemical formula 2, MeFe_2O_4, chemical formula 3, AFe_12O_19, or chemical formula 4, R_3Fe_5O_12. In chemical formula 1, M is early transition metal, X contains at least one of carbon and nitrogen, and n is an integer of 1 to 3. In chemical formula 2, Me is one or more elements selected from Ni, Mn, Zn, Cu, Co, Fe, Li, Mg, Cr, Ca and Ba. In chemical formula 3, A is one or more elements selected from Ba, Co, Ni, Mn, Zn, Cu, Fe, Li, Mg, Cr and Ca. In chemical formula 4, R is one or more elements selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu. The present invention enhances electric conductivity and has excellent magnetic loss and dielectric loss characteristics.

Description

Technical Field [0001] The present invention relates to a silicon-carbide / silicon carbide / ferrite composite and a method for manufacturing the silicon / silicon carbide / ferrite composite.

More particularly, the present invention relates to a Vickers / silicon carbide / ferrite composite excellent in electric conductivity, magnetic loss and dielectric loss characteristics and a method for manufacturing the same.

BACKGROUND ART [0002] In recent years, electromagnetic interference (EMI) shielding of radio frequency radiation has become increasingly important in everyday life and military fields as the use of electromagnetic wave devices such as communication devices, wireless networks, and personal digital devices increases.

Ferrite is an electromagnetic wave absorber having excellent electromagnetic wave absorption ability, and is widely used in electromagnetic interface antennas, filters, inductance elements, and the like. However, since ferrite has no ductility, when ferrite is forcibly expanded by force, it is broken, the stability against temperature is insufficient, and mechanical strength is increased due to increase in density due to firing, so that it is difficult to increase the surface area .

Recently, a new two-dimensional structure of transition metal carbides and transition metal carbonitrides represented by MXene has been reported. Maxine is represented by the formula M _{n + 1} X _n , wherein M is an early transition metal, X is carbon or nitrogen, and n is 1, 2, or 3. Generally, the maxine is produced by peeling the A element layer from the MAX phase using hydrofluoric acid or ammonium bifluoride at room temperature or elevated temperature. MAX phase is represented by the chemical formula of M _{n + 1} AX _n, wherein M is (early transition metal) in front of the transition metal in the formula, A is the A-group element, and (usually 3A group elements or 4A element), X is carbon Or nitrogen, and n is 1, 2, 3 or 4.

Due to its metallic conductivity and excellent mechanical properties, Maxine can be applied to polymer composites and energy storage devices capable of inserting organic molecules and ions.

Recently, several kinds of maxines that can be used for EMI shielding are being studied. It has been reported that a Ti3C2Tx film with a thickness of 45 mu m can have an EMI shielding efficiency of 92 decibels, which is higher than other composites having similar thicknesses. Further, it can be effectively mixed with ferrite through the excellent hydrophilicity possessed by maxine, and can be easily applied to an electromagnetic interface antenna, a filter, and an inductance element.

On the other hand, Non-Patent Document 1 discloses a method of removing functional groups bound to the surface of a vigin through a pretreatment process for alkalizing and calcining to improve the electrical properties of Ti ₃ C ₂ maxine. However, Non-Patent Document 1 has difficulty in providing a radio wave absorber having excellent electrical conductivity, magnetic loss and dielectric loss characteristics.

Non-Patent Document 1: Materials Letters, 160 (2015), 537-540

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and it is an object of the present invention to provide a Vickers / silicon carbide / ferrite composite which can be applied as a radio wave absorber and has improved electrical conductivity and a method for manufacturing the same.

According to an aspect of the present invention,

MXene of Formula 1;

A ferrite of the following formula (2), (3) or (4) attached to the interlayer or surface of the maxine; And

There is provided a maxin / silicon carbide / ferrite complex comprising silicon carbide adhering to the interlayer or surface of the maxin:

[Chemical Formula 1]

M _{n + 1} X _n

(2)

MeFe ₂ O ₄

(3)

AFe ₁₂ O ₁₉

[Chemical Formula 4]

R ₃ Fe ₅ O ₁₂

In Formula 1,

M is an early transition metal;

X comprises at least one of carbon and nitrogen;

n is an integer from 1 to 3;

In Formula 2,

Me is at least one element selected from Ni, Mn, Zn, Cu, Co, Fe, Li, Mg, Cr, Ca and Ba;

In Formula 3, A is at least one element selected from Ba, Co, Ni, Mn, Zn, Cu, Fe, Li, Mg, Cr and Ca;

In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

According to another aspect of the present invention,

Preparing a dispersion comprising a maxine of Formula 1;

Preparing a salt solution comprising a ferrite element in a molar ratio corresponding to a stoichiometric ratio of elements of the ferrite of formula (2), (3) or (4) except for oxygen;

Mixing the maxin dispersion and silicon carbide with the salt solution to prepare a first mixed solution;

Adding the first mixed solution to an alkali solution to prepare a second mixed solution; And

Adjusting the acidity of the second mixed solution and then heating to produce a maxin / silicon carbide / ferrite composite powder;

/ RTI > silicon carbide / ferrite composite comprising:

[Chemical Formula 1]

M _{n + 1} X _n

(2)

MeFe ₂ O ₄

(3)

AFe ₁₂ O ₁₉

[Chemical Formula 4]

R ₃ Fe ₅ O ₁₂

In Formula 1,

M is an early transition metal;

X comprises at least one of carbon and nitrogen;

n is an integer from 1 to 3;

In Formula 2,

Me is at least one element selected from Ni, Mn, Zn, Cu, Co, Fe, Li, Mg, Cr, Ca and Ba;

In Formula 3, A is at least one element selected from Ba, Co, Ni, Mn, Zn, Cu, Fe, Li, Mg, Cr and Ca;

In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

According to one aspect of the present invention, it is possible to provide a Vickin / silicon carbide / ferrite composite having improved electrical conductivity and excellent magnetic loss and dielectric loss characteristics by manufacturing a Vickin / silicon carbide / ferrite composite.

1 is an SEM image of Ti ₃ C ₂ T _x maxine.
FIG. 2 is a flowchart schematically showing a method of manufacturing a maxin / silicon carbide / ferrite composite according to another aspect of the present invention.
3 is a graph showing an XRD pattern analysis of a maxin / silicon carbide / ferrite composite produced by the method of Example 1. Fig.
4 is a SEM image of a maxin / silicon carbide / ferrite composite prepared by the method of Example 1. Fig.
5 is a graph showing a hysteresis loop of a maxin / silicon carbide / ferrite composite produced by the method of Example 1. Fig.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, which will be readily apparent to those skilled in the art. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly illustrate the present invention, parts not related to the description are omitted, and similar parts are denoted by like reference characters throughout the specification.

The terms used in this specification will be briefly described, and the present invention will be described in detail.

While the present invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, the term used in the present invention should be defined based on the meaning of the term, not on the name of a simple term, but on the entire contents of the present invention.

When an element is referred to as "including" an element throughout the specification, it is to be understood that the element may include other elements as well, without departing from the spirit or scope of the present invention.

Throughout the specification, "T _x " means functional groups bound to the maxin surface. Generally, the functional groups bonded to the surface of the vigin can be O, OH, and F, but the kind thereof is not limited.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

According to an aspect of the present invention,

MXene of Formula 1; A ferrite of the following formula (2), (3) or (4) attached to the interlayer or surface of the maxine; And silicon carbide adhering to an interlayer or a surface of the maxin. The present invention also provides a maxin / silicon carbide / ferrite composite including the above.

[Chemical Formula 1]

M _{n + 1} X _n

(2)

MeFe ₂ O ₄

(3)

AFe ₁₂ O ₁₉

[Chemical Formula 4]

R ₃ Fe ₅ O ₁₂

Wherein M is at least one of carbon and nitrogen, n is an integer of 1 to 3, and Me is at least one element selected from the group consisting of Ni, Mn, Zn Wherein A is at least one element selected from the group consisting of Cu, Co, Fe, Li, Mg, Cr, Ca and Ba. And Ca. In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

The maxin / silicon carbide / ferrite composite according to one aspect of the present invention can possess excellent electrical conductivity, magnetic loss and dielectric loss characteristics and can be used as a radio wave absorber.

FIG. 1 is a SEM image of Ti ₃ C ₂ T _x , a type of Vax. Referring to FIG. 1, a maxin is a two-dimensional layered structure, and layers constituting an atom are stacked to form a multi-layer structure. As such a two-dimensional multilayer structure, Vax is lightweight and has a low density and can be easily separated from each other, and thus can be used as an electromagnetic wave absorber in various fields.

In the maxin / silicon carbide / ferrite composite according to one embodiment of the present invention, the ferrite particles are attached to the interlayer or surface of the maxin. Ferrite particles adhere to the interlayer and the surface of the externally exposed maxine, and the maxin / silicon carbide / ferrite composite can have excellent magnetic loss characteristics.

The maxin / silicon carbide / ferrite composite according to one embodiment of the present invention has improved electrical conductivity by forming a three-dimensional conductive network and has an electric conductivity that is 5 to 10 times higher than that of pure ferrite at room temperature or lower than 260K .

In a maxin / silicon carbide / ferrite composite according to an embodiment of the present invention, the silicon carbide particles are attached to the interlayer or surface of the maxine. The maxin / silicon carbide / ferrite complex with silicon carbide particles attached to the interlayer and surface of the maxin can have excellent dielectric loss characteristics.

According to an embodiment of the present invention, ferrite may be attached to the surface of the silicon carbide particles. Nano-sized ferrite particles can be attached to the surface or inside of micro-sized silicon carbide particles by covalent bonding or the like. As the ferrite particles adhere to the surface or inside of the silicon carbide particles, the three-dimensional conductive network of the maxin / silicon carbide / ferrite composite can be further improved and the interlayer bonding force of the maxin can be improved.

According to one embodiment of the present invention, the maxin / silicon carbide / ferrite complex may contain 0.1 to 99.9% by weight of maxine. The maxin / silicon carbide / ferrite composite may comprise from 0.1% to 99.9% by weight of the maxin, and the remainder may be silicon carbide and ferrite. Specifically, the maxine may be included in an amount of 0.1% to 50% by weight based on the total weight of the maxin / silicon carbide / ferrite complex, more specifically 0.1% to 25% by weight of maxine based on the total weight of the maxin / silicon carbide / ferrite complex. have. However, the weight% of the above-mentioned maxine is only an illustrative example, and the weight% of the maxine can be adjusted depending on the application in which the maxin / silicon carbide / ferrite complex is used.

For example, when the maxin / silicon carbide / ferrite complex according to one embodiment of the present invention is used as a radio wave absorber, the maxin is 0.1 wt% to 25 wt% based on the total weight of the maxin / silicon carbide / ferrite composite, The silicon carbide may be contained in an amount of 40 to 60 wt%, and the ferrite may be contained in an amount of 35 to 55 wt%. In addition, based on the total weight of the maxin / silicon carbide / ferrite composite, the maxine may be comprised between 2 wt% and 7 wt%, the silicon carbide may be comprised between 45 wt% and 55 wt%, and the ferrite may be included between 40 wt% and 50 wt%

According to one embodiment of the present invention Maxine is _{Ti 2 C, V 2 C,} Nb 2 C, (Ti 0.5, Nb 0.5) 2 CT x, Ti 3 C 2, Ti 3 CN, (V 0.5, Cr 0.5) 3 C ₂ , Ta ₄ C _3, and Nb ₄ C ₃ .

The maxin / silicon carbide / ferrite composite according to an embodiment of the present invention may have excellent impedance matching. Therefore, the maxin / silicon carbide / ferrite composite can be used as an electromagnetic wave absorber used in an electromagnetic interface antenna, a filter, an inductance element, and the like. In addition, the maxin / silicon carbide / ferrite composite can be used in electromagnetic interface devices used in low temperature conditions. For example, it can be used in a radio wave absorber or a higher order mode loader used at a low temperature, and can be used as a radio wave absorber of an electromagnetic interface device used in space.

The maxin / silicon carbide / ferrite composites can be prepared, for example, by chemical co-precipitation method, solid phase ball milling, sol-gel method, high-temperature synthesis method, or a co-precipitation hydrothermal synthesis method. It is preferable to use the chemical coprecipitation method so that the ferrite particles and the silicon carbide particles can be effectively adhered to the interlayer and the surface of the vigor exposed to the outside. It should be noted, however, that the above-described methods are illustrative only and are not intended to limit the invention.

FIG. 2 is a flowchart illustrating a method of manufacturing a maxin / silicon carbide / ferrite composite according to another aspect of the present invention.

According to another aspect of the present invention, there is provided a method for producing a ferrite magnesia comprising the steps of (S100) preparing a dispersion containing a maxine of formula (1), a molar ratio corresponding to a stoichiometric ratio of elements of oxygen, Preparing a salt solution containing an element of ferrite (S200), mixing a maxin dispersion and silicon carbide with a salt solution to prepare a first mixed solution (S300), adding the first mixed solution to the alkali solution (S500) of preparing a mixture of VCS / silicon carbide / ferrite composite by adjusting the acidity of the second mixed solution and then heating to prepare a VCSIN / silicon carbide / ferrite composite A method can be provided.

[Chemical Formula 1]

M _{n + 1} X _n

(2)

MeFe ₂ O ₄

(3)

AFe ₁₂ O ₁₉

[Chemical Formula 4]

R ₃ Fe ₅ O ₁₂

Wherein M is at least one of carbon and nitrogen, n is an integer of 1 to 3, and Me is at least one element selected from the group consisting of Ni, Mn, Zn Wherein A is at least one element selected from the group consisting of Cu, Co, Fe, Li, Mg, Cr, Ca and Ba. And Ca. In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.

According to one embodiment of the present invention, a maxine can be produced by etching an element A from a compound represented by the following formula (5): < EMI ID =

[Chemical Formula 5]

M _{n + 1} AX _n

Wherein M is an early transition metal and A is an element selected from Al, Si, P, S, Ga, As, In, Sn, Tl and Pb and X is an element selected from the group consisting of carbon and nitrogen And n is an integer of 1 to 3,

For example, the maxine can be produced by etching the element A from the compound represented by Chemical Formula 5 using hydrofluoric acid or ammonium bifluoride at room temperature or elevated temperature. In the above formula (5), A may be an element of group 13 to group 16, but a group 13 element or a group 14 element may be preferable.

In S100, the dispersion may contain at least one of sodium lignin sulfonate, sodium dodecyl benzene sulfonate or oleylamine as a dispersing agent. However, the kind of the dispersant described above is only an example for explanation, and the kind of the dispersant is not limited.

In S200, the salt solution may be prepared by adjusting the molar ratio of the ferrite element to correspond to the stoichiometric ratio of the elements of the ferrite contained in the maxin / silicon carbide / ferrite composite except oxygen. For example, Ni (NO ₃ ) ₂ , Zn (NO ₃ ) _2, and Fe (NO ₃ ) ₃ (corresponding to the stoichiometric ratio of ferrite Ni _0.5 Zn _0.5 Fe ₂ O ₄ included in the maxin / silicon carbide / Is adjusted to Ni: Zn: Fe = 0.5: 0.5: 2 (molar ratio).

In S300, the maxin dispersion, the silicon carbide and the salt solution may be mixed so that the maxin of the maxin / silicon carbide / ferrite complex is 0.1 wt% to 99.9 wt%.

For example, the ferrite may be contained in an amount of 0.1 wt% to 25 wt% of the maxine, 40 wt% to 60 wt% of silicon carbide, and 35 wt% to 55 wt% of ferrite, based on the total weight of the maxin / silicon carbide / , Maxine dispersion, silicon carbide powder and salt solution can be mixed. In addition, it is preferable that the amount of the ferrite is in the range of 2 to 7% by weight, the silicon carbide is in the range of 45 to 55% by weight and the ferrite is in the range of 40 to 50% by weight based on the total weight of the maxin / silicon carbide / ferrite composite. Dispersion liquid, silicon carbide powder and salt solution may be mixed.

In S400, the alkali solution may include at least one of KOH, NaOH or NH ₃ H ₂ O. However, the kind of the alkali solution is not limited to the above-mentioned examples. In step S500, the acidity of the second mixed solution may be adjusted to a pH of 7 to 12. In order to adjust the acidity of the second mixed solution, for example, nitric acid, hydrochloric acid, sulfuric acid, and acetic acid may be used.

In S500, the second mixed solution may be heated to 20 DEG C to 90 DEG C and stirred. The second mixed solution can be heated and stirred using a known method.

According to an embodiment of the present invention, the method may further comprise the step of sintering the maxin / silicon carbide / ferrite composite powder to prepare a bulk / silicon carbide / ferrite composite bulk (not shown). The maxin / silicon carbide / ferrite composite powder can be sintered using known methods. For example, microwave technology, spark plasma sintering technology may be used. However, the sintering method is not limited to the above example.

Depending on the field of application, the size or shape of the maxin / silicon carbide / ferrite complex can be controlled. For example, in the form of a powder or bulk, slurry, low temperature or high temperature spray, silk-screen printing, slipping cast coating .

Hereinafter, the present invention will be described in more detail with reference to examples. These embodiments are merely illustrative and do not limit the technical scope of the present invention.

Example 1

Ferrite is Ni _0.5 Zn _0.5 Fe ₂ O ₄ was used, Maxine is Ti ₃ C ₂ was used as the T _x, Ti ₃ C ₂ T _x, SiC and Ni _0.5 Zn _0.5 Fe ₂ O _4, respectively 5%, 50 The maxine / silicon carbide / ferrite complex containing 45 wt%, 45 wt% was prepared as follows.

(1) 0.5 g of Ti ₃ C ₂ T _x was added to a supersaturated sodium lignin sulfonate solution, and ultrasonic dispersion was performed for 1 hour to prepare a maxine dispersion.

(2) Ni _0.5 Zn _0.5 Ni so as to correspond to the stoichiometric ratio of _{Fe 2 O 4 (NO 3)} 2, Zn (NO 3) 2 and Fe (NO _{3) 3} is Ni: Zn: Fe = 0.5: 0.5: 2 (Molar ratio) to prepare a salt solution. The vixin dispersion and SiC prepared above were added to the salt solution and magnetic stirring and ultrasonic dispersion were performed for 30 minutes to prepare a first mixed solution.

(3) The first mixed solution was added to a NaOH solution having a concentration of 1 mol / L to prepare a second mixed solution, and the pH of the second mixed solution was adjusted to pH 10.4 to 10.6. The slurry was washed with deionized water 5 times and dried at 80 ° C. to obtain a slurry containing 5 wt% of Ti ₃ C ₂ T _x , , 50% by weight of SiC and 45% by weight of Ni _0.5 Zn _0.5 Fe ₂ O ₄ .

XRD analysis

3 is a graph showing an XRD pattern analysis of a maxin / silicon carbide / ferrite composite produced by the method of Example 1. Fig. As shown in FIG. 3, peaks of Ni _0.5 Zn _0.5 Fe ₂ O ₄ and SiC were confirmed, but peaks of Ti ₃ C ₂ T _x used as maxine were not confirmed. This is because 5% by weight of maxine is contained at a lower level of the total weight of the maxine / silicon carbide / ferrite complex, and silicon carbide and ferrite are attached to the interlayer and the surface of the maxine.

SEM analysis

4 is a SEM image of a maxin / silicon carbide / ferrite composite prepared by the method of Example 1. Fig. As shown in FIG. 4, the Ni _0.5 Zn _0.5 Fe ₂ O ₄ ferrite nanoparticles and the SiC microparticles were attached to the interlayer and surface of the externally exposed Ti ₃ C ₂ T _x max, and the maxin / silicon carbide / ferrite composite . It was also confirmed that Ni _0.5 Zn _0.5 Fe ₂ O ₄ ferrite nanoparticles were attached to the surface of the SiC microparticles.

Self history analysis

5 is a graph showing a hysteresis loop of a maxin / silicon carbide / ferrite composite produced by the method of Example 1. Fig. As shown in FIG. 5, it was confirmed that the maxin / silicon carbide / ferrite composite according to an embodiment of the present invention has almost zero coercive force and residual magnetization. Also, the saturation sagnetization value of the maxin / silicon carbide / ferrite composite was found to be about 26.7 emu / g.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

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

Claims (11)

MXene of Formula 1;
A ferrite of the following formula (2), (3) or (4) attached to the interlayer or surface of the maxine; And
A silicon carbide adhered to the interlayer or surface of the maxine; a maxine / silicon carbide / ferrite composite comprising:
[Chemical Formula 1]
M _{n + 1} X _n
(2)
MeFe ₂ O ₄
(3)
AFe ₁₂ O ₁₉
[Chemical Formula 4]
R ₃ Fe ₅ O ₁₂
In Formula 1,
M is an early transition metal;
X comprises at least one of carbon and nitrogen;
n is an integer from 1 to 3;
In Formula 2,
Me is at least one element selected from Ni, Mn, Zn, Cu, Co, Fe, Li, Mg, Cr, Ca and Ba;
In Formula 3, A is at least one element selected from Ba, Co, Ni, Mn, Zn, Cu, Fe, Li, Mg, Cr and Ca;
In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.
The method according to claim 1,
Wherein the ferrite is attached to the surface of the silicon carbide particles.
The method according to claim 1,
Wherein the maxine is contained in an amount of 0.1 wt% to 99.9 wt%.
The method according to claim 1,
The Maxine is _{Ti 2 C, V 2 C,} Nb 2 C, (Ti 0.5, Nb 0.5) 2 CT x, Ti 3 C 2, Ti 3 CN, (V 0.5, Cr 0.5) 3 C 2, Ta 4 C 3 And Nb < ₄ > C < ₃ >.
Preparing a dispersion comprising a maxine of Formula 1;
Preparing a salt solution comprising a ferrite element in a molar ratio corresponding to a stoichiometric ratio of elements of the ferrite of formula (2), (3) or (4) except for oxygen;
Mixing the maxin dispersion and silicon carbide with the salt solution to prepare a first mixed solution;
Adding the first mixed solution to an alkali solution to prepare a second mixed solution; And
And adjusting the acidity of the second mixed solution and then heating to produce a maxin / silicon carbide / ferrite composite powder. The method of producing a maxin / silicon carbide / ferrite composite according to claim 1,
[Chemical Formula 1]
M _{n + 1} X _n
(2)
MeFe ₂ O ₄
(3)
AFe ₁₂ O ₁₉
[Chemical Formula 4]
R ₃ Fe ₅ O ₁₂
In Formula 1,
M is an early transition metal;
X comprises at least one of carbon and nitrogen;
n is an integer from 1 to 3;
In Formula 2,
Me is at least one element selected from Ni, Mn, Zn, Cu, Co, Fe, Li, Mg, Cr, Ca and Ba;
In Formula 3, A is at least one element selected from Ba, Co, Ni, Mn, Zn, Cu, Fe, Li, Mg, Cr and Ca;
In Formula 4, R is at least one element selected from Y, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu.
6. The method of claim 5,
Wherein the maxin dispersion, the silicon carbide and the salt solution are mixed such that the maxin of the maxin / silicon carbide / ferrite complex is 0.1 wt% to 99.9 wt%.
6. The method of claim 5,
Wherein the maxine is produced by etching an element A from a compound represented by the following formula (5): < EMI ID =
[Chemical Formula 5]
M _{n + 1} AX _n
In Formula 5,
M is an early transition metal;
A is an element selected from Al, Si, P, S, Ga, As, In, Sn, Tl and Pb;
X comprises at least one of carbon and nitrogen;
n is an integer of 1 to 3;
6. The method of claim 5,
The vixin dispersion may be prepared by the preparation of a maxin / silicon carbide / ferrite complex comprising at least one dispersant selected from the group consisting of sodium lignin sulfonate, sodium dodecyl benzene sulfonate or oleylamine. Way.
6. The method of claim 5,
The method of Maxine / SiC / ferrite composite of the alkali solution include at least one of KOH, NaOH or NH ₃ H ₂ O.
6. The method of claim 5,
Wherein the acidity of the second mixed solution is adjusted to a pH of from 7 to 12. < RTI ID = 0.0 > 11. < / RTI >
6. The method of claim 5,
Wherein the second mixed solution is heated to 20 ° C to 90 ° C.

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