KR20120135463A - Cathode material for fuel cell, and cathode for fuel cell and solid oxide fuel cell including the material - Google Patents

Abstract

PURPOSE: A positive electrode material for a fuel cell is provided to maintain low electrode resistance at a low temperature of 800°C or less by reducing polarization resistance of a positive electrode in a solid oxide fuel cell. CONSTITUTION: A positive electrode material for a fuel cell comprises a first metal oxide which has a perovskite structure, and a second metal oxide with a spinel structure. The comprised amount of the first metal oxide and the second metal oxide are 60-99 weight% and 1-40 weight%, respectively. A positive electrode for a fuel cell comprises the positive electrode material. A solid oxide fuel cell comprises a positive electrode which comprises the positive electrode material, a negative electrode which is arranged to face with the positive electrode, and a solid oxide electrolyte arranged between the positive electrode and negative electrode. [Reference numerals] (AA) Comparative embodiment 5; (BB) Embodiment 7; (CC) Embodiment 8

Description

Anode material for fuel cell, anode and solid oxide fuel cell for fuel cell comprising the material {Cathode material for fuel cell, and cathode for fuel cell and solid oxide fuel cell including the material}

A cathode material for a fuel cell, a fuel cell anode including the anode material, a manufacturing method thereof, and a solid oxide fuel cell employing the material are provided.

Solid oxide fuel cell (SOFC) is a high-efficiency, environmentally friendly electrochemical power generation technology that directly converts the chemical energy of fuel gas into electrical energy, and uses a solid oxide having ion conductivity as an electrolyte. SOFCs have many advantages over other types of fuel cells, such as relatively inexpensive materials, relatively high tolerances to fuel impurities, hybrid power generation capability, and high efficiency. The use of hydrocarbon-based fuels directly, without the need, can simplify and reduce the cost of fuel cell systems. SOFC is the cathode, oxygen gas fuel such as hydrogen or a hydrocarbon is oxidized with oxygen ions it takes place the ion-conducting solid oxide electrolyte that is ^{conductive-anode} is reduced, and oxygen ions ^{(O 2) (O 2)} .

Existing SOFCs operate at high temperatures in the range of 800 to 1,000 ° C. Therefore, high-temperature alloys or expensive ceramic materials that must withstand high temperatures must be used. There is a problem. In addition, there is a problem of overall cost increase, which is the biggest obstacle to commercialization.

Accordingly, many studies are underway to lower the operating temperature of SOFC below 800 ° C. However, reducing the operating temperature dramatically increases the electrical resistance of the SOFC anode material, which in turn serves as a major cause of reducing the power density of the SOFC. As described above, since the reduction of the operating temperature of the SOFC greatly affects the size of the anode resistance, attempts have been actively made to lower the anode resistance in the SOFC for mid-low temperature.

One aspect of the present invention is to provide a cathode material for a fuel cell that can reduce the polarization resistance of the anode.

Another aspect of the present invention is to provide a fuel cell anode comprising the anode material for the fuel cell.

Another aspect of the present invention to provide a solid oxide fuel cell comprising the anode for the fuel cell.

According to one aspect of the invention,

A first metal oxide having a perovskite structure; And

A cathode material for a fuel cell is provided, including a second metal oxide having a spinel structure.

The first metal oxide may be represented by the following Chemical Formula 1.

[Formula 1]

ABO _{3 ± δ}

Wherein A is at least one element selected from lanthanide elements and alkaline earth metal elements,

B is at least one element selected from transition metal elements,

? represents an excess of oxygen or a lack of oxygen.

According to one embodiment, the first metal oxide may be represented by the following formula (2).

[Formula 2]

A ' _{1- x} A " _x B'O _{3 ± δ}

In the above formula, A 'is at least one element selected from Ba, La and Sm,

A "is at least one element selected from Sr, Ca and Ba, which is different from A '

B 'is at least one element selected from Mn, Fe, Co, Ni, Cu, Ti, Nb,

0 ≦ x <1,

? represents an excess of oxygen or a lack of oxygen.

According to one embodiment, the first metal oxide is barium strontium cobalt iron oxide (BSCF), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF), lanthanum strontium chromium manganese oxide (LSCM), lanthanum strontium manganese Oxide (LSM), lanthanum strontium iron oxide (LSF), and samarium strontium cobalt oxide (SSC).

The second metal oxide may be represented by the following Chemical Formula 3.

(3)

M ₃ O ₄

Wherein M is at least one selected from Co, Fe, Mn, V, Ti, Cr and alloys thereof.

In example embodiments, the second metal oxide may include at least one selected from Co ₃ O ₄ , Fe ₃ O _4, and Mn ₃ O ₄ .

Melting point of the second metal oxide may be 800 ° C to 1,800 ° C. More specifically, the melting point of the second metal oxide may be 900 ° C to 1,500 ° C.

According to one embodiment, in the anode material for the fuel cell, the first metal oxide may be included in the range of 60 to 99% by weight, and the second metal oxide may be included in the range of 1 to 40% by weight. More specifically, the first metal oxide may be included in the range of 70 to 95% by weight, and the second metal oxide may be included in the range of 5 to 30% by weight. More specifically, the first metal oxide may be included in the range of 20 to 95% by weight, and the second metal oxide may be included in the range of 5 to 20% by weight.

In example embodiments, the cathode material for the fuel cell may include a third metal oxide having a fluorite crystal structure in addition to the first metal oxide and the second metal oxide. According to one embodiment, the third metal oxide may be a ceria-based metal oxide doped with one or more lanthanum heteroatoms.

According to one embodiment, the third metal oxide may be represented by the following formula (4).

[Formula 4]

Ce _{1 - y} M ' _y O ₂

Wherein M ′ is at least one selected from La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, and alloys thereof, and 0 <y <1.

In example embodiments, the third metal oxide represented by Chemical Formula 4 may be doped with at least two lanthanum dissimilar elements different from each other, and the average ion radius of the dissimilar element may range from 0.90 to 1.06. For example, the M 'may be double doped with Sm and at least one element selected from Pr, Nd, Pm, and alloys thereof.

According to one embodiment, when the third metal oxide is added, the weight ratio of the sum of the first metal oxide and the second metal oxide and the third metal oxide may be 99: 1 to 60:40. More specifically, the weight ratio of the sum of the first metal oxide and the second metal oxide to the third metal oxide may be 90:10 to 70:30, and more specifically 85:15 to 75:25.

According to another aspect of the invention, there is provided a fuel cell anode comprising the anode material for the fuel cell.

According to another aspect of the present invention,

Preparing a solution including the anode material for the fuel cell; And

It provides a method for producing a positive electrode for a fuel cell comprising a; heat treatment after coating the solution on a substrate.

According to one embodiment, the heat treatment step may be carried out at a temperature of 700 ℃ or more, less than 1000 ℃, for example, the heat treatment may be performed at a temperature of 800 ℃ to 900 ℃.

According to another aspect of the present invention,

A cathode including the anode material for the fuel cell;

A cathode disposed opposite the anode; And

There is provided a solid oxide fuel cell comprising a; solid oxide electrolyte disposed between the anode and the cathode.

According to one embodiment, the solid oxide electrolyte may include at least one selected from zirconia-based, ceria-based and lanthanum gallate-based solid electrolyte. More specifically, the solid oxide electrolyte is zirconia doped or not doped with at least one of yttrium and scandium; Ceria doped or undoped with at least one of gadolinium, samarium, lanthanum, ytterbium and neodymium; And lanthanum gallate doped or undoped with at least one of strontium and magnesium.

According to an embodiment, the solid oxide fuel cell may further include an electrical current collecting layer on an outer side surface of the anode. For example, the current collector layer may include at least one selected from the group consisting of lanthanum cobalt oxide (LaCoO ₃ ), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF), and lanthanum strontium iron oxide (LSF). It may include.

According to one embodiment, the solid oxide fuel cell may further include a functional layer for preventing or inhibiting a reaction between them between the anode and the solid oxide electrolyte. For example, the functional layer may include at least one selected from the group consisting of gadolinium-doped ceria (GDC), samarium-doped ceria (SDC), and yttrium-doped ceria (YDC).

The anode material for a fuel cell according to an embodiment of the present invention can maintain a low electrode resistance even at a low temperature of less than 800 ℃ by reducing the polarization resistance of the anode in a solid oxide fuel cell. By employing the cathode material, a solid oxide fuel cell that can be operated at a low temperature of 800 ° C. or less can be provided.

1 is a cross-sectional view schematically showing the structure of a solid oxide fuel cell according to one embodiment.
Figure 2 is an anode material and each BSCF of Preparation _{1-5 (Ba 0 .5 Sr 0 .5} Co 0 .8 Fe 0 .2 O 3) , and is a comparison of the X-ray diffraction pattern of Co ₃ O ₄ graph .
Figure 3 is a positive electrode material, and each BSCF of Preparation _{1-5 (Ba 0 .5 Sr 0 .5} Co 0 .8 Fe 0 .2 O 3) and the conductivity measurement results of Co ₃ O _4.
4 is an IV measurement result of the unit cell of Example 1.
5 is an IV measurement result of a comparative single cell of Comparative Example 1.
6 is an IV measurement result of the unit cell of Example 2.
7 is an IV measurement result of a comparative single battery cell of Comparative Example 2.
8 is an IV measurement result of the unit cell of Example 3.
9 is an IV measurement result of a comparative single battery cell of Comparative Example 3.
10 is an IV measurement result of the unit cell of Example 4.
11 is an IV measurement result of the unit cell of Example 5.
12 shows impedance measurement results of symmetric cells manufactured in Example 6 and Comparative Example 4. FIG.
FIG. 13 is a result of impedance measurement of a symmetric cell manufactured in Example 7. FIG.

EMBODIMENT OF THE INVENTION Hereinafter, specific embodiment of this invention is described in detail.

One aspect of the present invention provides a cathode material for a fuel cell comprising a first metal oxide having a perovskite structure and a second metal oxide having a spinel structure. According to one embodiment, the anode material for a fuel cell may further include a third metal oxide having a fluorite crystal structure.

In general, the electrochemical reaction of a solid oxide fuel cell includes an anode reaction in which the oxygen gas O ₂ of the cathode changes to oxygen ions O ^{2 -} as shown in the following reaction formula, and oxygen that has moved through the fuel (H ₂ or hydrocarbon) and the electrolyte of the anode. It consists of a cathode reaction in which ions react.

<Reaction Scheme>

Positive ^{_{electrode: 1/2 O 2 + 2e - -}} > O 2 -

_{^{Anode: H 2 + O 2 - -}} > H 2 O + 2e -

In the anode (air electrode) of solid oxide fuel cell, oxygen adsorbed on the surface of electrode moves to triple phase boundary where electrolyte, cathode and pore meet through dissociation and surface diffusion to obtain electrons to become oxygen ions Since ions move to the anode through the electrolyte, increasing the area of the three-phase interface in which the anode reaction occurs can increase the electrode reaction rate. The anode material for a fuel cell according to an embodiment includes a second metal oxide having a spinel structure together with a first metal oxide having a perovskite structure, and optionally a third metal oxide having a fluorite crystal structure. By further including, it is possible to increase the area of the three-phase interface in which the anodic reaction can occur can greatly increase the electrode activity at low temperatures and reduce the polarization resistance of the anode.

According to one embodiment, the first metal oxide having the perovskite structure may be represented by the following formula (1).

[Formula 1]

ABO _{3 ± δ}

Wherein A is at least one element selected from lanthanide elements and alkaline earth metal elements,

B is at least one element selected from transition metal elements,

? represents an excess of oxygen or a lack of oxygen.

Here, δ is a value that makes the perovskite-type metal oxide electrically neutral, and represents an excess of oxygen or a lack of oxygen. For example, the δ may have a range of 0 ≦ δ ≦ 0.3.

According to an embodiment, the first metal oxide of the perovskite structure may be a mixed inonic and electronic conductor (MIEC) material having both ionic and electronic conductivity in terms of excellent electrode activity at low temperatures. have. The ion / electron conductive mixed conductor is a single phase mixed conductor material having both high electron conductivity and high ion conductivity, and has a high oxygen diffusion coefficient and a charge exchange reaction rate coefficient, thereby reducing the oxygen reaction on the surface of the entire electrode as well as the three phase interface. Since this may occur, the electrode activity at low temperatures is excellent and may contribute to lowering the operating temperature of the SOFC. As such a mixed conductor, the first metal oxide of the perovskite structure may be represented by, for example, the following Chemical Formula 2.

[Formula 2]

A ' _{1- x} A " _x B'O _{3 ± δ}

In the above formula, A 'is at least one element selected from Ba, La and Sm,

A "is at least one element selected from Sr, Ca and Ba, which is different from A '

B 'is at least one element selected from Mn, Fe, Co, Ni, Cu, Ti, Nb,

0 ≦ x <1,

? represents an excess of oxygen or a lack of oxygen.

For example, δ may have a range of 0 ≦ δ ≦ 0.3.

Examples of such first metal oxides include barium strontium cobalt iron oxide (BSCF), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF), lanthanum strontium chromium manganese oxide (LSCM), and lanthanum strontium iron oxide (LSF) ) And samarium strontium cobalt oxide (SSC). Specifically, Ba _{1 - x} Sr _x Co _{1 - y} Fe _y O ₃ (wherein 0.1 ≦ _x ≦ 0.5, 0.05 ≦ _y ≦ 0.5), and La _{1 - x} Sr _x Fe _{1 - y} Co _y O ₃ (where , 0.1 ≦ _x ≦ 0.4, 0.05 ≦ _y ≦ 0.5), Sm _{1 - x} Sr _x CoO ₃ (here, 0.1 ≦ _x ≦ 0.5), and the like. For _{example, Ba 0 .5 Sr 0 .5 Co} 0 .8 Fe 0 .2 O 3, La 0 .6 Sr 0 .4 Co 0 .2 Fe 0 .8 O 3, Sm 0 .5 Sr 0 .5 CoO ₃ and the like can be used. These first metal oxides may be used alone or in combination of two or more thereof.

In addition, the anode material for a fuel cell includes a second metal oxide having a spinel structure together with the first metal oxide having the perovskite structure. The spinel structure is a crystal structure found in the oxide represented by the chemical formula XY ₂ O ₄ , and usually shows ferromagnetic or ferrimagnetic, and oxygen atoms occupy almost a face-centered cubic structure, and X ^{2 +} is tetrahedral position surrounded by four oxygen atoms. a, and Y ^{3 +} metal atom is a front (正), which accounts for the six oxygen atoms surrounded octahedral spinel structure and a tetrahedral position Y ^{3 +} occupies again in the octahedral position is X ^{2 +} and Y ^{3 +} occupied by half It is divided into a reverse spinel structure. In either case, the unit grid contains eight XY ₂ O ₄ .

According to one embodiment, the second metal oxide having the spinel structure may be represented by the following formula (3).

(3)

M ₃ O ₄

Wherein M is at least one selected from Co, Fe, Mn, V, Ti, Cr and alloys thereof.

A second metal oxide of the formula (3) accounting for M ^{2 +} a tetrahedral position as a mixed valence compound (mixed valence compound) has a positive spinel structure M ^{3 +} a, which accounts for octahedral positions. According to one embodiment, at least one selected from Co ₃ O ₄ , Fe ₃ O _4, and Mn ₃ O ₄ may be used as the second metal oxide.

The second metal oxide of the spinel structure can suppress the formation of a non-conductive layer that causes a decrease in performance by enabling the anode coating at a low temperature during the formation of the anode of the solid oxide fuel cell, and the adhesion between the electrolyte and the anode material ( It can give an effect of improving attachment.

In general, the heat treatment temperature of the low-temperature perovskite oxide anode material for forming a cathode of a solid oxide fuel cell is 1000 ℃ or more. This high temperature heat treatment forms a non-conductive phase such as SrZrO ₃ , La ₂ Zr ₂ O _7, or the like as a reaction by-product between the perovskite-based cathode material and the zirconia-based electrolyte. These insulator phases exhibit low electrical conductivity and reduce electrode activity, resulting in a sharp increase in electrode resistance as well as electrolyte resistance. Accordingly, a ceria-based functional layer may be inserted between the perovskite-based anode and the zirconia-based electrolyte in order to prevent the formation of the insulator phase. However, this approach can reduce the increase in resistance by inhibiting the reaction between the anode material and the electrolyte, but it is not only inevitable to increase the resistance due to unwanted reaction between Seira and zirconia, but also causes mechanical problems such as mismatch of coefficient of thermal expansion. . In addition, since the ceria-based compound used as a functional layer is usually a difficult material for sintering, there is a disadvantage in terms of cost and process in order to precisely coat it between the anode and the electrolyte.

In contrast, in the anode material for a fuel cell according to an aspect of the present invention, by adding a second metal oxide having a spinel structure to the first metal oxide having a perovskite structure, the heat treatment temperature of the cathode material is lowered to less than 1000 ° C. In addition, the reduction of the heat treatment temperature may inhibit the reaction between the positive electrode and the electrolyte to prevent the formation of the non-conductive phase as much as possible. Thus, it is possible to apply the fuel cell cathode material directly on the zirconia-based electrolyte without using a reaction prevention layer between the anode and the electrolyte.

In order to reduce the heat treatment temperature in this manner, it is preferable that the melting point of the second metal oxide having the spinel structure is low. For example, the melting point of the second metal oxide may be 800 ° C to 1,800 ° C. More specifically, the melting point of the second metal oxide may be 900 ° C to 1,500 ° C. If the melting point of the second metal oxide is lower than 800 ° C., it is unsuitable in consideration of the heat treatment temperature in manufacturing the cell. Melting point refers to the temperature obtained by the coexistence of liquid and solid phases of a substance by equilibrium. The melting point under one atmosphere is called the melting point of the substance. Melting point can be measured through phase change (equilibrium between solid state and liquid state) or calorie change while changing the temperature of the material under 1 atm.

In the anode material for the fuel cell, the content of the first metal oxide having the perovskite structure and the second metal oxide having the spinel structure may be determined in consideration of effects such as electrical conductivity, anode resistance, power density, and the like. For example, the first metal oxide may be included in the range of 60 to 99% by weight, and the second metal oxide may be included in the range of 1 to 40% by weight. According to one embodiment, the first metal oxide may be included in the range of 70 to 95% by weight and the second metal oxide may be included in the range of 5 to 30% by weight. More specifically, the first metal oxide may be included in the range of 80 to 95% by weight, and the second metal oxide may be included in the range of 5 to 20% by weight.

According to an embodiment, the anode material for fuel cell may include a third metal oxide having a fluorite crystal structure in addition to the first metal oxide and the second metal oxide to increase ion conductivity. According to one embodiment, the third metal oxide may be a ceria-based metal oxide doped with one or more lanthanum heteroatoms.

According to one embodiment, the third metal oxide may be represented by the following formula (4).

[Formula 4]

Ce _{1 - y} M ' _y O ₂

Wherein M ′ is at least one selected from La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, and alloys thereof, and 0 <y <1.

The third metal oxide of such a fluorite crystal structure has high ion conductivity and low electron conductivity. The high ionic conductivity of the third metal oxide may compensate for the insufficient ion conductivity of the perovskite material, thereby contributing to an increase in the anode reaction rate. In addition, it has a high melting point (eg, CeO ₂ :> 2000 ° C.) compared to a perovskite material (eg, BSCF: 1180 ° C.), thereby improving durability.

According to an embodiment, the third metal oxide represented by Chemical Formula 4 may be doped with at least two lanthanum dissimilar elements different from each other, and the average ion radius of the dissimilar element may range from 0.90 to 1.06. More specifically, the average ion radius may be 0.96 to 0.98. If the average ion radius of the hetero element is in the above range, the ion conductivity may be high. For example, the hetero element M 'doped with ceria in the third metal oxide may be doped with at least two hetero elements selected from Sm, Pr, Nd, Pm, and alloys thereof in the lanthanide element. More specifically, M 'may include another dopant selected from Pr, Nd, Pm, and alloys thereof, while necessarily including Sm as a dopant.

Doping amount y of the hetero element M 'doped in ceria in the third metal oxide of Formula 4 may be 0 <y <1, specifically 0 <y ≤ 0.5, more specifically 0 <y ≤ 0.3 Can be.

According to one embodiment, when the third metal oxide is added, the weight ratio of the sum of the first metal oxide and the second metal oxide and the third metal oxide may be 99: 1 to 60:40. More specifically, the weight ratio of the sum of the first metal oxide and the second metal oxide to the third metal oxide may be 90:10 to 70:30, and more specifically 85:15 to 75:25. According to one embodiment, it may be 80:20.

Another aspect of the present invention provides a fuel cell anode including the fuel cell anode material described above. The anode may be particularly useful as a cathode of a solid oxide fuel cell.

Another aspect of the present invention provides a method for manufacturing the anode for fuel cell. The fuel cell anode manufacturing method includes the steps of preparing a solution containing the anode material for a fuel cell described above; And it provides a method for producing a positive electrode for a fuel cell comprising the step of coating the solution on a substrate and heat treatment.

For example, the above-described anode material for a fuel cell, that is, the first metal oxide having the perovskite structure and the second metal oxide having the spinel structure are mixed with a solvent to prepare a slurry solution, and the slurry solution is prescribed. By coating on the substrate of the heat treatment, the anode for fuel cells can be produced. The slurry solution may further include a third metal oxide having a fluorite structure in addition to the first metal oxide and the second metal oxide.

The substrate on which the slurry solution is coated may be a solid oxide electrolyte, for example, a solid oxide electrolyte including at least one selected from zirconia-based, ceria-based and lanthanum gallate-based solid electrolytes. Specific examples include zirconia-based or doped with at least one of yttrium and scandium; Ceria based or not doped with at least one of gadolinium, samarium, lanthanum, ytterbium and neodymium; And a lanthanum gallate system, which is doped or undoped with at least one of strontium and magnesium, and a solid oxide electrolyte including at least one selected from the group consisting of lanthanum gallates.

Here, the slurry solution may be directly coated on the solid oxide electrolyte using various coating methods such as screen printing and dip coating. However, it is not excluded that the solid oxide electrolyte as the substrate for coating the solution may further include a functional layer such as a reaction prevention layer in order to more effectively prevent a reaction between the electrolyte and the electrode.

As such, the solution-coated substrate is heat-treated to form an anode layer. The heat treatment may be carried out at a temperature of 700 ℃ or less, less than 1000 ℃. For example, the heat treatment may be performed at a temperature of 800 ℃ to 900 ℃. By heat treatment in the above temperature range, the polarization resistance of the anode is reduced without changing the electrical properties and microstructures of the perovskite structure first metal oxide and spinel structure second metal oxide contained in the anode material for fuel cell. The anode layer which can be made can be manufactured. When considering the operating temperature of the low-temperature SOFC is usually 800 ℃ or less, the anode prepared at the heat treatment temperature can be stably function as a mixed conductor even after the SOFC operation. The heat treatment is performed at a low temperature compared to the temperature for heat-treating the perovskite-based positive electrode material, the reduction of the heat treatment temperature can prevent the formation of the non-conductive phase as possible by inhibiting the reaction between the positive electrode and the electrolyte.

In the fuel cell anode manufactured as described above, a second anode layer and / or an electrical current collector layer including a general anode material used in the art may be further formed as necessary.

In another aspect, the present invention, the anode comprising the anode material for the fuel cell; A cathode disposed opposite the anode; And a solid oxide electrolyte disposed between the anode and the cathode.

1 is a cross-sectional view schematically showing the structure of a solid oxide fuel cell according to one embodiment. Referring to FIG. 1, in the solid oxide fuel cell 10, an anode 12 and a cathode 13 are disposed on both sides of the solid oxide electrolyte 11.

The solid oxide electrolyte 11 must be dense so that air and fuel are not mixed, and have high oxygen ion conductivity and low electron conductivity. In addition, since the positive electrode 12 and the negative electrode 13 having a large oxygen partial pressure difference are positioned at both sides of the electrolyte 11, it is necessary to maintain the above physical properties in a wide oxygen partial pressure region.

The material constituting the solid oxide electrolyte 11 is not particularly limited as long as it can be generally used in the art, and includes at least one selected from zirconia-based, ceria-based and lanthanum gallate-based solid electrolytes. can do. For example, the solid oxide electrolyte 11 may include a zirconia based doped or undoped with at least one of yttrium and scandium; Ceria based or not doped with at least one of gadolinium, samarium, lanthanum, ytterbium and neodymium; And at least one selected from the group consisting of a lanthanum gallate system doped or undoped with at least one of strontium and magnesium; a stabilized zirconia system such as yttria stabilized zirconia (YSZ) and scandia stabilized zirconia (ScSZ); Ceria systems doped with rare earth elements such as samaria-doped ceria (SDC), gadolinia-doped ceria (GDC) and the like; Other LSGM ((La, Sr) (Ga, Mg) O ₃ ) systems can be used.

The solid oxide electrolyte 11 may have a thickness of about 10 nm to about 100 μm. For example, the thickness of the solid oxide electrolyte 11 may be 100 nm to 50 μm.

The cathode 13 (electrode) serves as electrochemical oxidation and charge transfer of the fuel. Therefore, it is preferable to use a cathode catalyst which is chemically stable and has a similar thermal expansion coefficient to the electrolytic material. The cathode 13 may include cermet in which a material for forming the solid oxide electrolyte 11 and nickel oxide are mixed. For example, when YSZ is used as an electrolyte, a Ni / YSZ composite (ceramic-metallic composite) may be used as the negative electrode 13. In addition, a pure metal such as Ru / YSZ Somer, Ni, Co, Ru, or Pt may be used as the material of the anode 13, but is not limited thereto. The negative electrode 13 may further include activated carbon as necessary. The cathode 13 may have a porosity so that fuel gas can be diffused well.

The negative electrode 13 may have a thickness of about 1 μm to 1000 μm. For example, the thickness of the cathode 13 may be 5 to 100 μm.

The anode 12 reduces the oxygen gas to oxygen ions and maintains a constant oxygen partial pressure by continuously flowing air to the anode 12. As described above, the anode 12 includes a fuel cell anode material including a first metal oxide having a perovskite structure and a second metal oxide having a spinel structure. Since the anode material for the fuel cell is as described above, a detailed description thereof will be omitted.

The positive electrode 12 may have a thickness of about 1 μm to about 100 μm. For example, the thickness of the first anode 12 may be 5 to 50 μm.

It is preferable that the anode 12 has porosity so that oxygen gas can be diffused and entered. The anode 12 is prevented or suppressed from reacting with the solid oxide electrolyte 11 due to the low-temperature heat treatment during the manufacturing process, and the generation of the non-conductive layer therebetween. However, it may further include a functional layer between the anode 12 and the solid oxide electrolyte 11 to prevent the reaction therebetween more effectively, if necessary. Such functional layers may include, for example, at least one selected from the group consisting of gadolinium doped ceria (GDC), samarium doped ceria (SDC), and yttrium doped ceria (YDC). The functional layer may have a thickness ranging from 1 to 50 μm, for example, from 2 to 10 μm.

According to an embodiment, the solid oxide fuel cell 10 may further include an electrical current collector layer including an electron conductor on at least one side of the anode 12, for example, an outer side of the anode 12. . The electric current collector layer may serve as a current collector for collecting electricity in the anode structure.

The electrical current collector layer may be, for example, lanthanum cobalt oxide (LaCoO ₃ ), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF), lanthanum strontium manganese oxide (LSM), and lanthanum strontium iron oxide (LSF) It may include at least one selected from the group consisting of. The electrical current collector layer may be used alone or in combination of two or more of the materials listed above. It is also possible to use a single layer or a plurality of stacked structures using these materials.

Since the solid oxide fuel cell can be manufactured by a conventional method known in the art, a detailed description thereof will be omitted here. In addition, the solid oxide fuel cell may be applied to various structures such as a cylindrical stack, a flat tubular stack, and a planar type stack.

Hereinafter, the present invention will be exemplified by the following examples, but the protection scope of the present invention is not limited only to the following examples.

Manufacturing example  1: Fabrication of Anode Material (1)

A perovskite material _{Ba 0 .5 Sr 0 .5 Co 0} .8 Fe 0 .2 O 3 Powders were synthesized using the EDTA-citric method. _{Specifically, Ba (NO 3) 2 3.5630g} , Sr (NO 3) 2 2.8853g, Co (NO 3) 3? 6H 2 O 6.3485g, Fe (NO 3) 3? 9H 2 O 2.2031g EDTA and 9.15 6 g and citric acid were added to 150 ml of distilled water and stirred using a magnetic bar until completely dissolved. The solution was held on a hotplate at 250 ° C. for 12 hours to remove organic components and a dry powder was obtained. By the two-hours' heat treatment of the powder obtained in 900 ℃ Ba _{0 .5} having a perovskite structure _{Sr 0 .5 Co 0 .8 Fe 0} .2 O 3 A powder was obtained (referred to below as 'BSCF', in connection with the Examples).

BSCF and the spinel structure of Co ₃ O ₄ commercial powder (Aldrich, mp 895 ℃) was measured in the content of 95wt% and 5wt%, respectively, ethanol media was mixed by ball milling using zirconia ball, mixing After completion, it was dried in an oven to obtain a positive electrode material.

Manufacturing example  2: Fabrication of Anode Material (2)

A positive electrode material was prepared in the same manner as in Preparation Example 1, except that BSCF and Co ₃ O ₄ were mixed in an amount of 90 wt% and 10 wt%, respectively.

Manufacturing example  3: Fabrication of Anode Material (3)

A positive electrode material was prepared in the same manner as in Preparation Example 1, except that BSCF and Co ₃ O ₄ were mixed in an amount of 80 wt% and 20 wt%, respectively.

Manufacturing example  4: Fabrication of Anode Material (4)

A positive electrode material was prepared in the same manner as in Preparation Example 1, except that BSCF and Co ₃ O ₄ were mixed in an amount of 70 wt% and 30 wt%, respectively.

Manufacturing example  5: Fabrication of Anode Material (5)

A positive electrode material was prepared in the same manner as in Preparation Example 1, except that BSCF and Co ₃ O ₄ were mixed in an amount of 60 wt% and 40 wt%, respectively.

Manufacturing example  6: Fabrication of Anode Material (6)

Instead BSCF as perovskite materials in Preparation Example _{1 La 0 .6 Sr 0 .4 Co} 0 .2 Fe 0 .8 O 3 Except for synthesizing (hereinafter referred to as 'LSCF') in connection with the embodiment, a cathode material in which LSCF 95 wt% and Co ₃ O ₄ 5 wt% were mixed was performed in the same process.

Here, the LSCF was synthesized using the EDTA-citric method like BSCF, La (NO ₃ ) ₃ ~ 6H ₂ O 5.3704g, Sr (NO ₃ ) ₂ 1.7490g, Co (NO ₃ ) _{3 ~} 6H ₂ O LSCF powder was synthesized using 1.2026 g of Fe (NO ₃ ) ₃ ˜ 9H ₂ O, 6.6778 g of EDTA, 9.24 g of EDTA, and 4.62 g of citric acid in 150 ml of distilled water.

Manufacturing example  7: Fabrication of Anode Material (7)

A perovskite material in Preparation Example 1 by the same procedure, except that instead of Sm _{0 .5} Sr _{0 .5} CoO ₃ used to synthesize (in connection with the embodiments, hereinafter referred to hereinafter 'SSC') BSCF A positive electrode material was prepared by mixing 95 wt% of SSC and 5 wt% of Co ₃ O ₄ .

Here, the SSC was synthesized using the EDTA-citric method as in BSCF, S963 (Sm (NO ₃ ) ₃ ~ 6H ₂ O 5.2963g, Sr (NO ₃ ) ₂ 2.5873g, Co (NO ₃ ) _{3 ~} 6H ₂ O SSC powder was synthesized by using 7.1163g, 9.62g of EDTA, and 4.81g of citric acid in 150ml of distilled water.

Manufacturing example  8: Fabrication of Anode Material (8)

The same procedure as in Preparation Example 1, except using a mixture of BSCF 95wt% and Fe ₃ O ₄ 5wt% using a Fe ₃ O ₄ commercial powder (Aldrich, mp 1538 ℃) of the spinel structure instead of Co ₃ O ₄ The anode material was prepared.

Manufacturing example  9: Fabrication of Anode Material (9)

The same procedure as in Preparation Example 1, except for mixing BSCF 95wt% and Mn ₃ O ₄ 5wt% using Mn ₃ O ₄ commercial powder (Aldrich, mp 1564 ℃) of the spinel structure instead of Co ₃ O ₄ The anode material was prepared.

Manufacturing example  10: Fabrication of Anode Material (10)

Fluoro as light materials were synthesized by the _{SNDC (Ce 0 .8 Sm 0 .15} Nd 0 .05 O 2) powdered solid-phase reaction method (solid state reaction) the. Specifically, 7.993 g of CeO _2, 1.518 g of Sm ₂ O _{3 and} 0.488 g of Nd ₂ O _{3 were} placed in a plastic barrel together with 100 ml of ethanol and commercial zirconia balls and ball milled for 12 hours. After ball milling it was maintained on a hotplate at 80 ° C. for 10 hours to obtain dry powder. The obtained powder was heat treated at 1200 ° C. for 2 hours to obtain a SNDC powder having a fluorite structure.

BSCF of the perovskite structure obtained in Preparation Example 1, Co ₃ O ₄ commercial powder of the spinel structure (Aldrich) and SNDC of the polite structure were measured in the content of 72wt%, 8wt%, 20wt%, respectively, ethanol The media were subjected to ball milling using zirconia balls and mixed, and dried in an oven after mixing was completed to obtain a positive electrode material. The above content corresponds to 0.8 {(BSCF) 0.9 + (Co3O4) 0.1} + 0.2SNDC.

Evaluation example  1: anode material XRD  Pattern measurement

In order to determine the reaction between the perovskite material and the spinel material, the cathode material of Preparation Example 1-5 was heat-treated at 1000 ° C., and then X-ray diffraction patterns were measured using CuKα rays, and the results are illustrated. 2 is shown. In order to compare the X-ray diffraction patterns, the X-ray diffraction patterns of each of the BSCF and Co ₃ O ₄ used in Preparation Example 1 are shown together in FIG. 7.

As shown in FIG. 2, Co ₃ O positive electrode material comprising a BSCF and Co ₃ O ₄ was changed to a content of ₄ is found that, even after heat treatment at 1000 ℃ and held each BSCF phase and Co ₃ O ₄ phase, and , No other second phase was found. This means that the obtained positive electrode material is in a physically mixed state.

Evaluation example  2: Measurement of conductivity of anode material

A 4-probe DC method was used to analyze the electrical conductivity of the cathode material of Preparation Example 1-5. Each cathode material powder was molded into a bulk shape using a metal mold, and then sintered to obtain a coin-shaped bulk body. A diamond cutter was used to cut the bulk body to form a square bar. The width, length and height of the square bar were 1.5 cm, 0.3 cm and 0.3 cm, respectively. Thus prepared bulk was measured for electrical conductivity in air from 300 ℃ to 900 ℃ using a current-voltage source meter (K2400, Keithley) and the results are shown in FIG. In order to compare the electrical conductivity, the results of measuring the electrical conductivity of BSCF and Co ₃ O ₄ used in Preparation Example 1 are shown together in FIG. 3.

As shown in FIG. 3, the positive electrode material mixed with BSCF and Co ₃ O ₄ showed higher or similar electrical conductivity than BSCF in the SOFC operating temperature range of 500 ° C. or higher. In particular, the low-temperature SOFC below 800 ° C. It has been found that the anode material can be usefully applied in the operating temperature range.

Example  1-5: Single cell  Manufacture of cells

A composite material in which NiO and YSZ (Zr _{0 .84} Y _{0 .16} O ₂ ) were mixed as an anode supporter was used. The bulk body was manufactured by a die pressing method in a cylindrical shape (diameter: 30 mm, thickness: 1 mm).

YSZ% Sc ₂ O ₃ -doped ZrO ₂ ) was pressed on the anode support to have a thickness of 20 μm, and sintered at 1400 ° C. to form a solid electrolyte (SE).

1 g of each cathode material obtained in Preparation Examples 1 and 6-9 was prepared using 1 ml of commercial FCM Ink vehicle (VEH), and the screen was printed on the solid electrolyte with a thickness of 10 μm to coat the anode layer. The unit cell was completed by heat treatment at 800 ° C. for 2 hours.

Comparative example  1-3: Comparison Single cell  Manufacture of cells

In order to compare the power density of the positive electrode material used in Example 1-5, as the positive electrode material by BSCF synthesized in Preparative Example _{1 (Ba 0 .5 Sr 0 .5} Co 0 .8 Fe 0 .2 O 3) , the above prepared LSCF synthesized in example _{6 (La 0 .6 Sr 0 .4} Co 0 .2 Fe 0 .8 O 3) and respectively using a _{SSC (Sm 0.5 Sr 0.5 CoO 3} ) synthesized in Preparative example 7 Except that formed by coating the positive electrode layer, the same procedure as in Example 1-5 was carried out to complete the comparative unit cells 1, 2, 3 respectively.

Evaluation example  3: Current-Voltage and Power Density Measurements

I-V / I-P measurement (here, I: current, current, V: voltage, voltage, P: power density, and power) was performed on the unit cells of Examples 1-5 and Comparative Examples 1-3. When oxygen was added to the cathode (anode) and hydrogen gas was added to the anode (cathode), an OCV (open circuit voltage) of 1 V or more was obtained. The voltage-drop was measured by increasing the current from 0 A (amps) to several A to obtain I-V data. The measurement was made while increasing the current until the voltage became 0V. I-P can be obtained by calculating from I-V data. I-V and I-P measurement results are shown in FIGS. 4 to 11, respectively. 4 to 11, white dots are graphs plotting I-V relationships at respective measurement temperatures, and black dots are graphs plotting output density calculated from I-V graphs.

4 is an IV measurement result of a unit cell of Example 1 using a BSCF and Co ₃ O ₄ mixed cathode material, Figure 5 is an IV of a comparative unit cell of Comparative Example 1 applied only to the BSCF cathode material without Co ₃ O ₄ The measurement result. Referring to FIG. 4, a cathode layer mixed with BSCF (95 wt%) and Co ₃ O ₄ (5 wt%) coated on the cathode support zirconia solid electrolyte was found to have excellent fuel cell performance. That is, the maximum output density of about 1.2W / ㎠ at 750 ℃ was shown, and the maximum output density of about 0.8W / ㎠ at 700 ℃. This is a very good value for commonly known zirconia electrolyte cells. In the case of the comparative single cell of Comparative Example 1 in which only BSCF cathode material was applied without Co ₃ O ₄ , the performance between the BSCF and the zirconia solid electrolyte was significantly reduced.

6 is an IV measurement result of a unit cell of Example 2 using a mixed cathode material of LSCF and Co ₃ O ₄ , which are other perovskite materials, and FIG. 7 is a comparative example in which only an LSCF cathode material is applied without Co ₃ O ₄ . IV measurement result of the comparative single cell of 2. As shown in Figures 6 and 7, it can be seen that the anode layer mixed with LSCF and Co ₃ O ₄ has a very good fuel cell performance compared to that used with LSCF alone.

FIG. 8 is an IV measurement result of the unit cell of Example 3 using a mixed cathode material of SSC and Co ₃ O ₄ , which is another perovskite material, and FIG. 9 is a comparison of SSC cathode material without Co ₃ O ₄ . IV measurement result of the comparative unit cell of Example 3. As shown in FIGS. 8 and 9, it can be seen that the anode layer in which SSC and Co ₃ O ₄ are mixed is similarly excellent in fuel cell performance compared to that of SSC alone.

FIG. 10 is an IV measurement result of a unit cell of Example 4 using a mixed cathode material of Fe ₃ O ₄ , which is a BSCF and another spinel material, and FIG. 11 is an implementation using a mixed cathode material of BSCF and Mn ₃ O ₄ . IV measurement result of the unit cell of Example 5. As shown in FIGS. 10 and 11, the cathode material in which Fe ₃ O ₄ or Mn ₃ O ₄ is added to the perovskite material is also excellent in fuel cell performance as in the case of adding Co ₃ O ₄ .

The peak power densities of the unit cell of Example 1-5 and Comparative Example 1-3 are summarized in Table 1 below.

drawing Anode Composition Cell performance
(peak power density, mW / cm ² ) 600 ℃ 650 ℃ 700 ℃ Example 1 4 BSCF (95 wt%) + Co ₃ O ₄ (5 wt%) 440 1458 1770 Comparative Example 1 5 BSCF 30 60 116 Example 2 6 LSCF (95 wt%) + Co ₃ O ₄ (5 wt%) 336 581 876 Comparative Example 2 7 LSCF 7 15 54 Example 3 8 SSC (95 wt%) + Co ₃ O ₄ (5 wt%) 222 465 805 Comparative Example 3 9 SSC 18 27 44 Example 4 10 BSCF (95 wt%) + Fe ₃ O ₄ (5 wt%) 263 460 849 Example 5 11 BSCF (95 wt%) + Mn ₃ O ₄ (5 wt%) 387 552 832

Example  6: Symmetrical  Manufacture (1)

In order to confirm the effect of Co ₃ O ₄ with spinel structure and CoO with rock salt structure on the anode performance, a symmetric cell coated with a pair of anode layers on both sides of the electrolyte layer Was prepared.

In the symmetrical cell, the electrolyte layer was prepared using YSZ commercial powder (Tosoh commercial powder, TZ-8Y), die pressing the powder into a metal mold, and press CIP (cold isostatic press, 200 MPa pressure). After pressing), and sintered at 1550 ° C. to obtain a bulk molded article having a thickness of 1 mm.

Meanwhile, in order to form an anode layer on both ends of the electrolyte layer, 5 wt% of commercial powder Co ₃ O ₄ was used in a commercial powder LSCF (La _0.6 Sr _0.4 Co _0.2 Fe _0.8 O ₃ , Fuel Cell Materials, Inc.) (Vehicle, FCM). After mixing with a mortar using a mortar to prepare a slurry, the positive electrode layer was coated by screen printing to a thickness of 10μm on both ends of the YSZ electrolyte layer. After coating, the symmetric cell was completed by heat treatment at 800 ° C. for bonding with the electrolyte.

Comparative example  4: comparison Symmetrical  Manufacture (1)

A comparative symmetric cell was prepared in the same manner as in Example 6, except that CoO commercial powder having a lacsalt structure was added instead of Co ₃ O ₄ having a spinel structure.

Evaluation example  4: impedance measurement

The impedance of the symmetric cells prepared in Example 6 and Comparative Example 4 was measured in an air atmosphere, and the results are shown in FIG. 12. Materials mates 7260 was used as an impedance measuring instrument. In addition, the operating temperature of the unit cell was measured at 650 ℃ and 700 ℃.

In FIG. 12, the size of the semicircle (the diameter of the semicircle) is the size of the anode resistance R _ca. As shown in FIG. 12, the symmetric cell (Example 6) using the mixed anode material of LSCF and Co ₃ O ₄ was smaller in size than the symmetric cell (Comparative Example 4) using the mixed anode material of LSCF and CoO. . That is, at 700 ° C., the anode resistance of Example 6 is about 0.7 ohm cm ² , and the cathode resistance of Comparative Example 4 is about 0.9 ohm cm ² , and at 650 ° C., the anode resistance of Example 6 is about 2.0 ohm cm ² , and the cathode of Comparative Example 4 The resistance was about 2.6 ohm cm ² and the results are summarized in Table 2 below. 12 and Table 1 show that Co ₃ O ₄ having a spinel structure is an effective additive in terms of anode performance.

At 700 ° C
Anode Resistance (ohmcm ² ) At 650 ° C
Anode Resistance (ohmcm ² ) Example 6 0.7 2.0 Comparative Example 4 0.9 2.6

Example  7-8: Symmetrical  Manufacture (2)

A pair of anode layers were coated on both sides of the electrolyte layer in order to see the effect of changing electrode resistance when spinel structure Co ₃ O ₄ and fluorite structure SNDC were added to the perovskite structure BSCF. Symmetrical cells were prepared. In the symmetrical cell, the electrolyte layer was prepared using YSZ commercial powder (Tosoh commercial powder, TZ-8Y), die pressing the powder into a metal mold, and press CIP (cold isostatic press, 200 MPa pressure). After pressing), and sintered at 1550 ° C. to obtain a bulk molded article having a thickness of 1 mm. On both ends of the bulk molded body, a commercial coating of GDC (Fuel Cell Materials) commercial powder is coated and coated thereon, and the anode of BSCF + Co ₃ O ₄ (Preparation Example 2) and BSCF + Co ₃ O ₄ + SNDC (Preparation Example 10) is coated thereon. The anodes were coated by screen printing a slurry prepared by mixing materials with a mortar using a commercial solvent (Vehicle, FCM) to a thickness of 10 μm. After coating, BSCF + Co ₃ O ₄ was heat treated at 800 ° C., and BSCF + Co ₃ O ₄ + SNDC was heat treated at 900 ° C. to complete the symmetric cell.

Comparative example  4: comparison Symmetrical  Manufacture (2)

A comparative symmetric cell was prepared in the same manner as in Example 7, except that BSCF was used alone as a cathode material.

Evaluation example  5: Impedance measurement

The impedance of the symmetric cells prepared in Examples 7-8 and Comparative Example 4 was measured in an air atmosphere, and the results are shown in FIG. 13.

As in FIG. 12, the size of the semicircle (the diameter of the semicircle) in FIG. 13 is the size of the anode resistance R _ca. As shown in FIG. 13, the size of the semicircle of the symmetric cell (Example 7) using the BSCF + Co3O4 mixed anode material was smaller than that of the symmetric cell using the BSCF anode material alone (Comparative Example 5). The symmetrical cell (Example 8) in which SNDC was further added to Co 3 O 4 showed the smallest semicircle size. FIG. 13 shows that the ion conductor SNDC having a fluorite structure is an effective additive together with the spinel structure material (Co ₃ O ₄ ) in terms of anode performance. As in Fig. 12, the size of the semicircle (x-axis intercepts, R _p ) is the anode resistance (anode specific resistance).

Evaluation example  6: Anode Resistivity Measurement

The impedance of each cell was measured in air while varying the operating temperature of the symmetric cells prepared in Example 7-8 and Comparative Example 5. An Arrhenius plot of the anode resistivity (R _p ) of each symmetric cell with respect to operating temperature is shown in FIG. 14.

Referring to FIG. 14, the anode resistivity of the symmetric cell (Examples 7 and 8) using the BSCF + Co 3 O 4 and BSCF + Co 3 O 4 + SNDC mixed anode materials is the anode resistivity of the symmetric cell (Comparative Example 5) using the BSCF anode material alone. It can be seen that smaller. Among them, BSCF + Co3O4 + SNDC mixed anode material with enhanced ion conductivity showed the lowest anode resistivity (R _p ).

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 embodiments, but, on the contrary, . Accordingly, the scope of protection of the present invention should be determined by the appended claims.

10: solid oxide fuel cell 11: solid oxide electrolyte
12: anode 13: cathode

Claims (21)

A first metal oxide having a perovskite structure; And
A cathode material for a fuel cell comprising; a second metal oxide having a spinel structure. The method of claim 1,
The first metal oxide is a fuel cell anode material represented by Formula 1 below:
[Formula 1]
ABO _{3 ± δ}
Wherein A is at least one element selected from lanthanide elements and alkaline earth metal elements,
B is at least one element selected from transition metal elements,
? represents an excess of oxygen or a lack of oxygen. The method of claim 2,
The first metal oxide is a fuel cell anode material represented by the following formula (2):
(2)
A ' _{1- x} A " _x B'O _{3 ± δ}
Wherein A 'is at least one element selected from Ba, La and Sm,
A ″ is at least one element selected from Sr, Ca, and Ba, and is different from A ′.
B 'is at least one element selected from Mn, Fe, Co, Ni, Cu, Ti, Nb, Cr and Sc,
0 ≦ x <1,
? represents an excess of oxygen or a lack of oxygen. The method of claim 1,
The first metal oxide is barium strontium cobalt iron oxide (BSCF), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF), lanthanum strontium chromium manganese oxide (LSCM), lanthanum strontium manganese oxide (LSM), lanthanum A cathode material for a fuel cell comprising at least one selected from strontium iron oxide (LSF) and samarium strontium cobalt oxide (SSC). The method of claim 1,
The second metal oxide is a cathode material for a fuel cell represented by Formula 3 below:
(3)
M ₃ O ₄
Wherein M is at least one selected from Co, Fe, Mn, V, Ti, Cr and alloys thereof. The method of claim 5,
The second metal oxide is a cathode material for a fuel cell comprising at least one selected from Co ₃ O ₄ , Fe ₃ O ₄ and Mn ₃ O ₄ . The method of claim 1,
Melting point of the second metal oxide (melting point) is a cathode material for a fuel cell is 800 ℃ to 1,800 ℃. The method of claim 7, wherein
Melting point of the second metal oxide (melting point) is a cathode material for a fuel cell is 900 ℃ to 1,500 ℃. The method of claim 1,
The first metal oxide is included in the range of 60 to 99% by weight, the second metal oxide is included in the range of 1 to 40% by weight of the cathode material for a fuel cell. 10. The method of claim 9,
The first metal oxide is included in the range of 70 to 95% by weight, the second metal oxide is included in the range of 5 to 30% by weight of the cathode material for a fuel cell. 10. The method of claim 9,
The first metal oxide is included in the range of 80 to 95% by weight, and the second metal oxide in the range of 5 to 20% by weight of the positive electrode material for a fuel cell. The method of claim 1,
A cathode material for a fuel cell further comprising a third metal oxide having a fluorite crystal structure. The method of claim 12,
The third metal oxide is a ceria-based metal oxide doped with one or more lanthanum heteroatoms. The method of claim 12,
The third metal oxide is a cathode material for a fuel cell represented by the following formula (4):
[Chemical Formula 4]
Ce _{1 - y} M ' _y O ₂
Wherein M ′ is at least one selected from La, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, and alloys thereof, and 0 <y <1. 15. The method of claim 14,
M 'is a cathode material for a fuel cell comprising Sm and at least one element selected from Pr, Nd, Pm, and alloys thereof. The method of claim 12,
The weight ratio of the sum of the first metal oxide and the second metal oxide to the third metal oxide is 99: 1 to 60:40. A fuel cell anode comprising the anode material for a fuel cell according to any one of claims 1 to 16. A positive electrode comprising a positive electrode material for a fuel cell according to any one of claims 1 to 16;
A cathode disposed opposite the anode; And
And a solid oxide electrolyte disposed between the anode and the cathode. 19. The method of claim 18,
And a solid oxide electrolyte comprising at least one selected from zirconia-based, ceria-based and lanthanum gallate-based solid electrolytes. 19. The method of claim 18,
Further comprising an electrical current collector layer on the outer side of the anode, the electrical current collector layer, lanthanum cobalt oxide (LaCoO ₃ ), lanthanum strontium cobalt oxide (LSC), lanthanum strontium cobalt iron oxide (LSCF) and lanthanum strontium iron oxide ( LSF) Solid oxide fuel cell comprising at least one selected from the group consisting of. 19. The method of claim 18,
Further comprising a functional layer to prevent or inhibit the reaction between the positive electrode and the solid oxide electrolyte, the functional layer is gadolinium doped ceria (GDC), samarium doped ceria (SDC) and yttrium dopedin ceria ( YDC) solid oxide fuel cell comprising at least one selected from the group consisting of.

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