KR102237821B1 - Metal oxide-based material, fuel cell comprising metal oxide-based material, and method of preparing fuel cell - Google Patents

Abstract

A first metal oxide represented by the following formula (1); And a metal oxide-based material including an alkaline earth metal oxide. Disclosed are a fuel cell including the same and a method of manufacturing the same.
<Formula 1>
Ce _(1.0-x) M _{1 (x)} O _(2-δ)
In Formula 1, M ₁ , x and δ are as described in the detailed description.

Description

Metal oxide-based material, fuel cell comprising metal oxide-based material, and method of preparing fuel cell}

Disclosed are a metal oxide-based material, a fuel cell including the same, and a method of manufacturing the same.

A fuel cell is a device that generates electricity by reacting fuel such as hydrogen or natural gas with oxygen and is recognized as one of the major energy technologies in the future due to its high efficiency, pollution-free, and noise-free characteristics.

The fuel cell includes an anode, an electrolyte layer, and a cathode.

As an electrolyte layer material, YSZ (yttria-stabilized zirconia), CSZ (Ca-doped ZrO ₂ ), GDC (Gd-doped CeO ₂ ) and perovskite structures with fluorite crystal structure LSGM Oxide materials such as lanthanum gallate doped with Sr and Mg in the composition of La-Sr-Ga-Mg-O are used.

As the anode material, lanthanum-strontium-manganese oxide (LSM) or lanthanum-strontium-cobalt-iron oxide (LSCF) or the like is used.

However, the lanthanum-strontium-cobalt-iron oxide (LSCF)-based cathode material may react with a zirconia-based electrolyte to form a nonconducting material. Since the efficiency of the fuel cell can be reduced due to the non-conductive material, it is required to prevent a reaction between the anode and the electrolyte layer.

An embodiment of the present invention discloses a metal oxide-based material.

Another embodiment of the present invention discloses a fuel cell including the metal oxide-based material.

Another embodiment of the present invention discloses a method of manufacturing the fuel cell.

An embodiment of the present invention, a first metal oxide represented by the following formula (1); And

Disclosed is a metal oxide-based material comprising an alkaline earth metal oxide:

<Formula 1>

Ce _(1.0-x) M _{1 (x)} O _(2-δ)

In Formula 1,

M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;

x is 0.01 to 0.30;

δ is a value that makes the first metal oxide electrically neutral.

The alkaline earth metal oxide may be at least one selected from MgO, CaO, SrO, and BaO.

The alkaline earth metal oxide may be MgO.

The alkaline earth metal oxide may be doped on the first metal oxide.

The content of the alkaline earth metal oxide may be greater than 0 mol% to 5 mol% or less.

In Formula 1, M ₁ may be Gd.

The metal oxide-based material may be represented by the following Formula 2:

<Formula 2>

Ce _(1.0-xy) M _{1 (x)} M _{2 (y)} O _(2-δ)

In Formula 2,

M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;

M ₂ is selected from Mg, Ca, Sr and Ba;

x is 0.01 to 0.30;

y is 0.01 to 0.05;

δ is a value that makes the metal oxide-based material electrically neutral.

Another embodiment of the present invention, the anode;

A negative electrode facing the positive electrode;

An electrolyte layer interposed between the positive electrode and the negative electrode; And

Disclosed is a fuel cell, which is interposed between the anode and the electrolyte layer, and includes a functional layer including the above-described metal oxide-based material.

The relative density of the functional layer may be 70% to 100%.

The relative density of the functional layer may be 90% to 100%.

The average particle size of the particles included in the functional layer may be 2.0㎛ to 6.0㎛.

The thickness of the functional layer may be 1 μm to 25 μm.

The anode may include at least one selected from lanthanum-strontium-cobalt-iron oxide (LSCF), lanthanum-strontium-iron oxide (LSF), and lanthanum-strontium-chromium oxide (LSC).

The electrolyte layer may include at least one selected from zirconia-based.

The electrolyte layer may be doped with one or more selected from Y, Sc, Sm and Gd.

Another embodiment of the present invention, forming a cathode;

Forming an electrolyte layer on the negative electrode;

Forming a functional layer on the electrolyte layer by aerosol deposition; And

Disclosed is a method of manufacturing a fuel cell including forming an anode on the functional layer.

The method of manufacturing the fuel cell may further include heat-treating the functional layer at 700 to 1000°C.

Even if the metal oxide-based material according to the embodiments of the present invention is heat-treated at a relatively low temperature, a dense structure can be formed. A fuel cell including such a metal oxide-based material has a high quality.

1 is a schematic diagram of a fuel cell according to an embodiment.
2 shows the results of X-ray diffraction analysis according to an embodiment.
3 shows the results of electrical conductivity analysis according to Example 1 and Comparative Example 2.
4 shows the results of SEM analysis according to Example 1.
5 shows the results of SEM analysis according to Example 2.
6 shows the results of SEM analysis according to Example 3.
7 shows the results of SEM analysis according to Example 4.
8 shows the results of SEM analysis according to Comparative Example 1.
9 shows the performance results according to the operating temperature of the fuel cell according to Evaluation Example 4.
10 shows performance results according to the presence or absence of a functional layer of a fuel cell according to Evaluation Example 5. FIG.

Hereinafter, a metal oxide-based material, a fuel cell including the same, and a method of manufacturing the same according to exemplary embodiments will be described in more detail.

A metal oxide-based material according to an embodiment may include a first metal oxide represented by the following Chemical Formula 1; And alkaline earth metal oxides:

<Formula 1>

Ce _(1.0-x) M _{1 (x)} O _(2-δ)

In Formula 1,

M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;

x is 0.01 to 0.30;

δ is a value that makes the first metal oxide electrically neutral.

The alkaline earth metal oxide acts as a sintering aid, and allows the metal oxide-based material to form a dense structure even when heat-treated at a relatively low temperature.

For example, the alkaline earth metal oxide may be at least one selected from MgO, CaO, SrO, and BaO, but is not limited thereto. As another example, the alkaline earth metal oxide may be MgO, but is not limited thereto.

The alkaline earth metal oxide may be doped on the first metal oxide, but is not limited thereto. That is, the alkaline earth metal included in the alkaline earth metal oxide may be included in the lattice constituting the metal oxide-based material, but is not limited thereto.

The content of the alkaline earth metal oxide may be greater than 0 mol% to 5 mol% or less, but is not limited thereto. For example, the content of the alkaline earth metal oxide may be 0.5 mol% or more, 1 mol% or more, 5 mol% or less, 3 mol% or less, or 2 mol% or less, but is not limited thereto. When the content of the alkaline earth metal oxide is within the above range, it is possible to form a dense structure even if the metal oxide-based material is heat-treated at a relatively low temperature.

The first metal oxide represented by Formula 1 may be ceria (CeO _{2 ) doped with a heterogeneous element (M 1 ).} For example, in Formula 1, M ₁ may be Gd, but is not limited thereto.

For example, in Formula 1, x may be 0.01 to 0.15, but is not limited thereto.

The value of δ varies depending on the oxidation state of the constituents of Formula 1, respectively. For example, in Formula 1, when the oxidation state of Ce is +3 and the oxidation state of M ₁ is +2, the value of δ is “1/2 + x/2”.

The metal oxide-based material may be represented by Formula 2 below, but is not limited thereto:

<Formula 2>

Ce _(1.0-x) M _{1 (xy)} M _{2 (y)} O _(2-δ)

In Formula 2,

M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;

M ₂ is selected from Mg, Ca, Sr and Ba;

x is 0.01 to 0.30;

y is 0.01 to 0.05;

δ is a value that makes the metal oxide-based material electrically neutral.

For example, in Formula 2, M ₁ may be Gd, but is not limited thereto.

For example, in Formula 2, M ₂ may be Mg, but is not limited thereto.

The value of δ varies depending on the oxidation state of the constituents of Formula 2, respectively. For example, in Formula 2, when the oxidation state of Ce is +3, and the oxidation states of M ₁ and M ₂ are each +2, the value of δ is “1/2 + x/2 + y/2” to be.

Hereinafter, a fuel cell and a manufacturing method thereof according to an embodiment of the present invention will be described in detail with reference to the drawings.

The fuel cell may be, for example, a solid oxide fuel cell.

The fuel cell includes a positive electrode; A negative electrode facing the positive electrode; An electrolyte layer interposed between the positive electrode and the negative electrode; And a functional layer interposed between the anode and the electrolyte layer and including the above-described metal oxide-based material.

1 is a cross-sectional view of a half-cell 10 including a functional layer 12 according to an embodiment of the present invention.

The half-cell 10 includes an electrolyte layer 11, a functional layer 12 and a positive electrode 13.

The electrolyte layer 11 may include at least one selected from the group consisting of scandia stabilized zirconia (ScSZ), yttria stabilized zirconia (YSZ), samarium-doped ceria (SDC), and gadolinium-doped ceria (GDC). Since the electrolyte layer 11 is generally required for high density characteristics, it can be formed by sintering an electrolyte (ie, ScSZ, YSZ, SDC, GDC, or a combination thereof) at a high temperature for a long time. In this case, the sintering treatment may be performed by heat treatment at about 1,450°C to 1,650°C for 6 hours to 10 hours.

The thickness of the electrolyte layer 11 is usually 10 nm to 100 μm, for example 100 nm to 50 μm.

The functional layer 12 prevents or suppresses a reaction between the electrolyte layer 11 and the anode 13 and prevents or suppresses the occurrence of a non-conductor layer (not shown) therebetween. The functional layer 12 may have a compact structure to perform this role. For example, the relative density of the functional layer 12 may be 70% to 100%, and as another example, it may be 90% to 100%, but is not limited thereto. The functional layer between the positive electrode and the electrolyte layer should be able to prevent the resistance value from increasing by forming a reaction phase with the electrolyte due to diffusion of the positive electrode element.If there are many pores in the functional layer, the reaction preventing function may not be performed and the ion conductivity Decrease can reduce performance. In addition, when the functional layer has an excessively dense structure, it is necessary to have limited pores since it may not be able to perform a reaction preventing function because it helps the diffusion of elements in the anode layer. In the functional layer including the metal oxide-based material according to an exemplary embodiment, by adjusting the relative density of the functional layer to 70% to 100%, a dense functional layer capable of effectively preventing diffusion of an anode element can be manufactured.

As a material for forming the functional layer 12, the above-described metal oxide-based material may be included.

The metal oxide-based material may be included in the form of particles. The average particle size of the particles may be 2.0 μm to 6.0 μm, but is not limited thereto. When the average particle size of the particles is within the above range, the structure of the functional layer may be dense.

The thickness of the functional layer 12 may be 1 μm to 25 μm. When the thickness of the functional layer 12 is within the above range, it may be sufficient to prevent or suppress a reaction between the electrolyte layer 11 and the anode 13.

The functional layer 12 may be formed on the electrolyte layer 11 by using a physical vapor deposition method (PVD). For example, the functional layer 12 may be formed using sputtering, pulse laser deposition (PLD), aerosol deposition, or the like, but is not limited thereto. As another example, the functional layer 12 may be formed using an aerosol deposition method, but is not limited thereto.

When forming the functional layer 12 using the aerosol deposition method, the powder of the metal oxide-based material including the first metal oxide and the alkaline earth metal oxide is transferred using a transport gas (for example, oxygen gas). It can be formed by colliding with the electrolyte layer 11 at a rate of 100 m/sec to 500 m/sec.

The metal oxide-based material powder may have an average particle size of 0.3 μm to 5 μm. If the average particle size is less than 0.3㎛, the energy impinging on the electrolyte layer is small, making it difficult to form a dense film. If the average particle size is more than 5㎛, it is difficult to form aerosol due to the large particle size of the powder. I can.

The functional layer 12 may be further heat-treated at 700°C to 1000°C. By using the metal oxide-based material for the functional layer 12, the functional layer can be dense even when heat-treated at a relatively low temperature.

The functional layer 12 may be further heat-treated for 1 hour to 5 hours, for example, 2 hours to 3 hours. By using the metal oxide-based material for the functional layer 12, even if heat treatment is performed for a relatively short period of time, the functional layer can be dense.

A solid oxide may be used as a material for forming the anode.

As the solid oxide, lanthanum-strontium-cobalt-iron oxide _{(La 0 .6 Sr 0 .4 Co} 0 .8 Fe 0 .2 O3, LSCF), lanthanum-strontium-iron oxide (LSF) and lanthanum-strontium-chromium One or more selected from oxides (LSC) can be used. For example, as the solid oxide, metal oxide particles having a perovskite-type crystal structure may be used, and (Sm,Sr)CoO ₃ , (La,Sr)MnO ₃ , (La,Sr Metal oxide particles such as )CoO ₃ , (La,Sr)(Fe,Co)O ₃ , (La,Sr)(Fe,Co,Ni)O _{3 may be exemplified.} The metal oxide particles described above may be used alone or in combination of two or more.

As a material for forming the anode, noble metals such as platinum, ruthenium, and palladium may be used.

As a material for forming the anode, lanthanum manganite doped with strontium, cobalt, iron, or the like may be used. For example, La is _{0 .8 Sr 0 .2 MnO 3 (} LSM), La 0 .6 Sr 0 .4 Co 0 .8 such as _{Fe 0 .2 O 3 (LSCF)} .

As a material for forming the negative electrode, a cermet in which a powder of a material forming the electrolyte layer 11 and nickel oxide are mixed may be used. For example, when YSZ is used as an electrolyte, a Ni/YSZ composite (ceramic-metallic composite) may be used as the negative electrode. In addition, Ru/YSZ thermal or pure metals such as Ni, Co, Ru, and Pt may be used as the negative electrode material, but the present invention is not limited thereto. The negative electrode may further include activated carbon as needed. It is preferable that the cathode has porosity so that fuel gas can be easily diffused into it.

The thickness of the negative electrode may be usually 1 to 1000 μm. For example, the thickness of the negative electrode may be 5 to 100 μm.

The solid oxide fuel cell 10 may further include an electric current collecting layer (not shown) including an electron conductor on at least one side of the anode 13, for example, an outer side of the anode 13. The electric current collector layer may serve as a current collector for collecting electricity in a positive electrode configuration.

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

Since the solid oxide fuel cell can be manufactured using a conventional method known in various documents 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 tubular stack, a flat tubular stack, and a planar type stack.

It will be described in more detail through the following examples and comparative examples. However, the examples are for illustrative purposes only, and the scope of the invention is not limited thereto.

Manufacturing example 1: Preparation of metal oxide-based material

The contents of cerium oxide, gadolinium oxide, and magnesium oxide were controlled so that the molar ratio of Ce:Gd:Mg was 0.9:0.09:0.01, and ball milled for 12 hours. Then, by drying the milled mixture and the ball, the heat treatment in an electric furnace _{Ce 0 .9 Gd 0 .09 Mg 0} .01 O 1. ₄₅ was obtained in the form of a powder.

Manufacturing example 2: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Mg 0.9: 0.08: to conduct, so that 0.02, except that the content of cerium oxide, gadolinium oxide, and magnesium oxide, and the mixture was controlled according to the same method as in Production Example 1 Ce _{0 .9} Gd _{0 .08} Mg _{0 .02} O _{1. 45} was obtained in the form of a powder.

Manufacturing example 3: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Mg 0.9: 0.07: conducted according to the same manner as in Preparation Example 1 except that the 0.03, and control the content of cerium oxide, gadolinium oxide, and magnesium oxide such that Ce Gd _{0 .9 0 .07} Mg _{0 .03} O _{1. 45} was obtained in the form of a powder.

Manufacturing example 4: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Mg 0.9: 0.06: conducted, except that the content of cerium oxide, gadolinium oxide, and magnesium oxide, and the mixture was controlled to be 0.04 in the same manner as in Production Example 1 Ce _{0 .9} Gd _{0 .06} Mg _{0 .04} O _{1. 45} was obtained in the form of a powder.

Manufacturing example 5: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Mg 0.9: 0.04: 0.06 is subjected to, cerium oxide, with the exception that the amount of gadolinium oxide and magnesium oxide, and the mixture was controlled according to the same method as in Production Example 1 Ce _{0 .9} Gd _{0 .04} Mg _{0 .06} O _{1. 45} was obtained in the form of a powder.

Manufacturing example 6: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Mg 0.9: 0.02: to conduct, so that 0.08, except that the content of cerium oxide, gadolinium oxide, and magnesium oxide, and the mixture was controlled according to the same method as in Production Example 1 Ce _{0 .9} Gd _{0 .02} Mg _{0 .08} O _{1. 45} was obtained in the form of a powder.

Manufacturing example 7: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Ca 0.9: 0.08: to conduct, so that 0.02, except that the content of cerium oxide, gadolinium oxide, and calcium oxide, and the mixture was controlled according to the same method as in Production Example 1 Ce _{0 .9} Gd _{0 .08} Ca _{0 .02} O _{1 . 45} was obtained in the form of a powder.

Manufacturing example 8: Preparation of metal oxide-based material

Ce: Gd: the molar ratio of Sr 0.9: 0.08: 0.02 and conducted such that, with the exception that the content of cerium oxide, gadolinium oxide, and strontium oxide, and the mixture was controlled according to the same method as in Production Example 1 Ce _{0 .9} Gd _{0 .08} Sr _{0 .02} O _{1 . 45} was obtained in the form of a powder.

Manufacturing example 9: Preparation of metal oxide-based material

Ce: Gd: Ba molar ratio of 0.9: 0.08: 0.02 so that, by and is prepared by the same procedure as in Preparation Example 1, except that the cerium oxide, gadolinium oxide, and barium oxide content was controlled Ce _{0 .9} Gd _{0. 08} Ba _{0 .02} O _{1 . 45} was obtained in the form of a powder.

Comparative Production Example : Preparation of metal oxide-based materials

Ce: the molar ratio of Gd 0.9: set at 0.1, and is conducted according to the same manner as in Preparation Example 1 to give a Ce _0.9 Gd _0.1 O _1.45 in a powder state, except that the cerium oxide, gadolinium oxide, and barium oxide content was controlled .

Example One: Bulk Produce

In order to analyze the relative density and electrical properties of the metal oxide-based material obtained according to Preparation Example 2, the obtained powder was put into a metal mold and pressed, and then heat-treated in air using an electric furnace at 1000°C for 3 hours to sinter to obtain a bulk body. Was prepared.

Example 2: Bulk Produce

A bulk body was manufactured using the same method as in Example 1, except that it was sintered at 900°C.

Example 3: Bulk Produce

A bulk body was manufactured using the same method as in Example 1, except that it was sintered at 800°C.

Example 4: Bulk Produce

A bulk body was prepared in the same manner as in Example 1, except that it was sintered at 700°C.

Example 5 to 12: Bulk Produce

A bulk body corresponding to each metal oxide-based material was obtained by following the same method as Example 1, except that the powder obtained according to Preparation Examples 1 and 3 to 9 was used instead of the powder obtained according to Preparation Example 2.

Comparative example One: Bulk Produce

Instead of the powder obtained according to Preparation Example 2, the powder obtained according to Comparative Preparation Example 1 was used, and a bulk body was obtained in the same manner as in Example 1, except that the powder was sintered at 1100°C.

Comparative example 2: Bulk Produce

Instead of the powder obtained according to Preparation Example 2, the powder obtained according to Comparative Preparation Example 1 was used, and a bulk body was obtained in the same manner as in Example 1, except that the powder was sintered at 1300°C.

Evaluation Example 1: Relative Density Analysis

In order to confirm the relative density of the bulk bodies of Examples 1 to 12, the relative density was measured by the Archimedean method. The Archimedean method is as described later.

Specimens of Examples 1 to 6 and Comparative Example 1 having a diameter of 10 mm and a thickness of 3 mm were prepared. After measuring the dry weight (W _dry ) of the specimen, the specimen was immersed in distilled water for 24 hours at room temperature to saturate the specimen with distilled water. At this time, between the top of the specimen and the water surface was 50 to 60 mm. Then, the specimen saturated with distilled water was suspended using a wire to measure the _{weight in water (W sup ).} Then, the sample saturated with distilled water was taken out, the distilled water on the surface was wiped off, and the saturated weight (W _sat ) was measured. Relative density (D) was calculated through Equation 1 below.

[Equation 1]

D = W _dry / (W _sat -W _sup ) × 100

The relative density results are shown in Table 1 below:

Relative density (%) Relative density (%) Example 1 91 Example 7 85 Example 2 88 Example 8 79 Example 3 85 Example 9 78 Example 4 76 Example 10 72 Example 5 88 Example 11 82 Example 6 90 Example 12 85 Comparative Example 1 63 Comparative Example 2 91

Evaluation example 2: X-ray diffraction analysis

Using an X-ray diffractometer equipped with a Cu target (available from XRD, X'pert, Philips), samples were analyzed for a range of 20° to 80° at a scan rate of 4°/min.

The results of the X-ray diffraction analysis are as shown in FIG. 2.

In FIG. 2, Evaluation Example 2 is a graph in which the powder of Preparation Example 2 was aerosol-deposited on an YSZ/NiO substrate, and after heat treatment at 900° C., X-ray diffraction analysis was performed. In FIG. 2, Comparative Example 1 is a graph of X-ray diffraction analysis after aerosol deposition of the powder of Preparation Example 2 on an YSZ/NiO substrate. In FIG. 2, Comparative Example 2 is a graph obtained by analyzing the powder of Preparation Example 2 by X-ray diffraction analysis.

Referring to Figure 2, it was confirmed that a single phase was formed.

Evaluation example 3: electrical conductivity analysis

The electrical conductivity of the bulk bodies prepared in Example 1 and Comparative Example 2 was measured using a WEIS system (available from OneAtech), in a frequency range of 100 kHz to 0.1 Hz, at 600 to 1000°C, and 100 mV at each temperature. The analysis was performed by applying an AC voltage and an open circuit voltage of amplitude.

The electrical conductivity analysis results are as shown in Fig. 3 and Table 2:

Measurement temperature (℃) Electrical conductivity of Example 1
(S/cm) Electrical conductivity of Comparative Example 2
(S/cm) 600 -1.18 -1.23 700 -1.02 -1.09 800 -0.88 -0.98 900 -0.81 -0.92 1000 -0.64 -0.75

3 and Table 2, it can be seen that the electrical conductivity of Example 1 is improved than that of Comparative Example 2.

Example 13: Manufacture of fuel cells

NiO was extruded into a cylindrical shape having a diameter of 1 cm and a thickness of 2 mm to form a negative electrode. On the cylindrical surface of the negative electrode, YSZ (10 mol% Sc ₂ O ₃ -doped ZrO ₂ ) slurry was dip coated and sintered at 1400°C to form an electrolyte layer having a thickness of 10 μm. Depositing a _{Ce 0 .9 Gd 0 .08 Mg 0} .02 O 1 .45 Powder of Preparation Example 2, on the cylindrical surface of the electrolyte layer, aerosol, and by heating at 900 ℃ to form a functional layer of 3㎛ thickness. Dip coating the _{LSCF (La 0 .6 Sr 0 .4} Co 0 .2 Fe 0 .8 O 3 -δ composition) slurry over a cylindrical surface of the functional layer, forming the thickness of the positive electrode subjected to heat treatment at 900 ℃ 30㎛ Thus, a button cell was manufactured. The button cell had a diameter of 2.6 cm.

Comparative example 3: Fabrication of Comparative Fuel Cell

NiO was extruded into a cylindrical shape having a diameter of 1 cm and a thickness of 2 mm to form a negative electrode. On the cylindrical surface of the negative electrode, YSZ (10 mol% Sc ₂ O ₃ -doped ZrO ₂ ) slurry was dip coated and sintered at 1400°C to form an electrolyte layer having a thickness of 10 μm. LSCF over the cylindrical surface of the electrolyte layer _{(La 0 .6 Sr 0 .4 Co} 0 .2 Fe 0 .8 O 3 -δ composition) dip-coating the slurry, and heat treated at 1200 ℃ form a positive electrode thickness of 30㎛ Thus, a button cell was manufactured. The button cell had a diameter of 2.6 cm.

Evaluation example 4: Evaluation of fuel cell performance according to operating temperature

The fuel cell manufactured in Example 13 was evaluated for performance. The fuel cell was heated from room temperature to 800° C., and H ₂ gas was injected into the cathode for 3 hours. Then, after cooling the fuel cell to a temperature to be evaluated, current and voltage were measured using a solartron 1287 while air was injected into the _{anode and H 2} O (3%)/H _{2 gas was injected into the cathode.} Here, Pt was used as the current collector. The evaluation temperatures were 600°C, 700°C and 800°C.

Then, the current density and voltage density were calculated in consideration of the measurement area of the fuel cell, and the results are shown in Table 3 and FIG. 9:

Evaluation temperature (℃) Power density (W/cm ² ) 600 0.97 700 1.27 800 1.63

Evaluation example 5: Functional layer Fuel cell performance evaluation according to the presence or absence

Performance evaluation was performed on the fuel cell manufactured in Example 13 and the comparative fuel cell manufactured in Comparative Example 3. After heating the fuel cell and the comparative fuel cell from room temperature to 800° C., H ₂ gas was injected into the cathode for 3 hours. Then, while injecting air into the anode of each fuel cell and the comparative fuel cell, and H ₂ O (3%)/H ₂ gas into the cathode, current and voltage were measured using a solartron 1287. Here, Pt was used as the current collector.

Then, the current density and voltage density were calculated in consideration of the measurement area of the fuel cell, and the results are shown in Table 4 and FIG. 10.

object Power density (W/cm ² ) Example 13 1.63 Comparative Example 3 1.48

Claims (17)

A first metal oxide represented by the following formula (1); And
Metal oxide-based material containing at least one alkaline earth metal oxide selected from CaO, SrO and BaO:
<Formula 1>
Ce _(1.0-x) M _1(x) O _(2-δ)
In Formula 1,
M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;
x is 0.01 to 0.30;
δ is a value that makes the first metal oxide electrically neutral. delete delete The method of claim 1,
The alkaline earth metal oxide is doped with the first metal oxide. The method of claim 1,
The content of the alkaline earth metal oxide is more than 0 mol% to 5 mol% or less, a metal oxide-based material. The method of claim 1,
M ₁ is Gd, a metal oxide-based material. The method of claim 1,
Metal oxide-based material represented by the following formula (2)
<Formula 2>
Ce _(1.0-xy) M _1(x) M _2(y) O _(2-δ)
In Formula 2,
M ₁ is selected from Gd, Sm, La, Yb, Zr, Pr and Nd;
M ₂ is selected from Ca, Sr and Ba;
x is 0.01 to 0.30;
y is 0.01 to 0.05;
δ is a value that makes the metal oxide-based material electrically neutral. anode;
A negative electrode facing the positive electrode;
An electrolyte layer interposed between the positive electrode and the negative electrode; And
A fuel cell comprising a functional layer interposed between the anode and the electrolyte layer and comprising a metal oxide-based material according to any one of claims 1 and 4 to 7. The method of claim 8,
The relative density of the functional layer is 70% to 100%, the fuel cell. The method of claim 8,
The fuel cell has a relative density of 90% to 100% of the functional layer. The method of claim 8,
The fuel cell, the average particle size of the particles included in the functional layer is 2.0㎛ to 6.0㎛. The method of claim 8,
The thickness of the functional layer is 1㎛ to 25㎛, fuel cell. The method of claim 8,
The anode comprises at least one selected from lanthanum-strontium-cobalt-iron oxide (LSCF), lanthanum-strontium-iron oxide (LSF), and lanthanum-strontium-chromium oxide (LSC). The method of claim 8,
The fuel cell, wherein the electrolyte layer includes at least one selected from zirconia-based. The method of claim 8,
The electrolyte layer is doped with at least one selected from Y, Sc, Sm and Gd, the fuel cell. Forming a cathode;
Forming an electrolyte layer on the negative electrode;
Forming a functional layer including the metal oxide-based material according to any one of claims 1 and 4 to 7 by an aerosol deposition method on the electrolyte layer; And
A method of manufacturing a fuel cell comprising forming an anode on the functional layer. The method of claim 16,
The method of manufacturing a fuel cell further comprising the step of heat-treating the functional layer at 700 to 1000°C.

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