WO2024014454A1 - Solid oxide electrolysis cell and solid oxide electrolysis cell system - Google Patents

Abstract

Provided is a solid oxide electrolysis cell (SOEC) comprising a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode, the SOEC further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode. The intermediate layer comprises cerium oxide, and the fuel electrode comprises a metal or metal oxide, and a compound A. The proportion of the metal or metal oxide in relation to the entire fuel electrode as a volume ratio in terms of metal is in the range of 40-80 vol%, and the metal includes at least one metal selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). The compound A includes a mayenite-type compound and/or a perovskite-type compound containing an alkaline earth metal element.

Description

Solid oxide electrolytic cells and solid oxide electrolytic cell systems

The present invention relates to a solid oxide electrolytic cell and a solid oxide electrolytic cell system.

In recent years, solid oxide electrolysis cells (SOEC) have been attracting attention as a highly efficient hydrogen fuel production method. In SOEC, water vapor and/or carbon dioxide can be electrolyzed at high temperatures to produce hydrogen and/or carbon monoxide.

In SOEC, the basic unit is a cell (single cell) that has two electrodes (oxygen electrode and fuel electrode) and a solid electrolyte layer placed between the two electrodes. A SOEC system is constructed by modularizing a multi-stack that is a combination of a plurality of these cell stacks.

JP2009-263741A

In order to increase the electrolytic efficiency of SOEC, research on optimizing its constituent parts is underway.

For example, in Patent Document 1, a cerium-based composite oxide layer called an intermediate layer is arranged between an electrolyte layer and each electrode, and a multilayer structure of a catalyst layer and a current collecting layer is used as an oxygen electrode. It is proposed to do so.

However, current SOECs have a problem in that the operating voltage changes during use. Therefore, there is a need for an SOEC that can suppress changes in operating voltage even during long-term operation.

The present invention has been made in view of this background, and an object of the present invention is to provide a SOEC that can suppress changes in operating voltage compared to conventional ones. Another object of the present invention is to provide a SOEC system including such a SOEC.

The present invention provides a solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
The fuel electrode includes a metal or a metal oxide and a compound A,
The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
A solid oxide type electrolytic cell is provided in which the compound A includes a mayenite type compound and/or a perovskite type compound containing an alkaline earth metal element.

Further, the present invention provides a solid oxide electrolytic cell system, comprising:
a module comprising a plurality of solid oxide electrolytic cell stacks, each solid oxide electrolytic cell being a solid oxide electrolytic cell having the characteristics described above;
a power supply device that supplies power to the module;
a gas supply device that supplies water vapor and/or carbon dioxide to the module;
a gas separation device that separates hydrogen and/or carbon monoxide generated from the module;
a storage device that stores the hydrogen and/or carbon monoxide separated by the gas separation device;
A solid oxide electrolytic cell system is provided having the following.

Furthermore, the present invention provides a solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
The fuel electrode includes a metal or a metal oxide and a compound A,
The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
The compound A contains an oxide containing an alkaline earth metal element and/or a rare earth element other than Sc and Y, and the ratio of the alkaline earth metal element and/or rare earth element other than Sc and Y to the metal is molar. A solid oxide type electrolytic cell is provided in which the ratio is 1.0% or more.

According to the present invention, it is possible to provide a SOEC that can suppress changes in operating voltage compared to conventional ones. Furthermore, the present invention can provide a SOEC system including such a SOEC.

1 is a cross-sectional view schematically showing an example of the configuration of a SOEC according to an embodiment of the present invention. 1 is a diagram schematically showing an example of the configuration of a system including a SOEC module according to an embodiment of the present invention. 1 is a flow diagram schematically showing an example of a method for manufacturing a SOEC according to an embodiment of the present invention. 1 is a graph showing changes over time in electrolysis voltage measured in a SOEC according to an embodiment of the present invention (cell 1) and a conventional SOEC (cell 21).

An embodiment of the present invention will be described below.

In one embodiment of the present invention, a solid oxide electrolytic cell includes a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
The fuel electrode includes a metal or a metal oxide and a compound A,
The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
A solid oxide type electrolytic cell is provided in which the compound A includes a mayenite type compound and/or a perovskite type compound containing an alkaline earth metal element.

In this application, a mayenite type compound has a C12A7 (12CaO.7Al ₂ O ₃ ) type crystal structure, and means a substance with a characteristic crystal structure having three-dimensionally connected cavities (cages). .

The skeleton that constitutes the cage of the mayenite-type compound is positively charged and includes 12 cage structures per unit cell. In the case of a representative substance with stoichiometry, 1/6 of this cage contains oxide ions inside to satisfy the electrical neutrality condition of the crystal. The oxide ions in this cage are particularly called free oxide ions because they are chemically bonded more loosely than other oxide ions constituting the crystal skeleton.

Representative materials of the mayenite type compound are, for example, 12CaO.7Al ₂ O ₃ , 12SrO.7Al ₂ O ₃ , and 12MgO.7Al ₂ O ₃ . However, in these materials, some of the cations (Ca, Al, Sr, and Mg) may be replaced with other cations.

Therefore, in this application, materials in which some of such cations are replaced with other cations are referred to as "○○-based mayenite-type compounds."

For example, in a 12CaO.7Al ₂ O ₃ compound, a material in which some of the Ca and/or Al sites are replaced with different cations is called a "12CaO.7Al ₂ O ₃ -based mayenite-type compound." . Similarly, in a 12SrO.7Al ₂ O ₃ compound, a material in which some of the Sr and/or Al sites are replaced with different cations is called a "12SrO.7Al ₂ O ₃ -based mayenite-type compound". Ru. In addition, in the 12MgO.7Al ₂ O ₃ compound, a material in which some of the Mg and/or Al sites are replaced with different cations is called a "12MgO.7Al ₂ O ₃ -based mayenite-type compound". .

In the SOEC according to an embodiment of the present invention, changes in operating voltage can be suppressed.

Although not bound by theory, in the SOEC according to an embodiment of the present invention, changes in operating voltage can be suppressed because deterioration of the three-phase interface is suppressed in the fuel electrode during use. It is believed that there is.

That is, in the SOEC according to one embodiment of the present invention, the fuel electrode includes compound A, that is, a mayenite-type compound and/or a perovskite-type compound containing an alkaline earth metal element, in addition to a metal or a metal oxide.

Such a compound A has a strong affinity for _CO2 . Therefore, during the electrolytic treatment of SOEC according to an embodiment of the present invention, the reactive gas CO ₂ is strongly adsorbed on the compound A. Therefore, during the reduction reaction at the fuel electrode, electrons are smoothly supplied to CO ₂ at the three-phase interface between the metal and compound A (the reaction field where the reaction gas, electrons, and ions meet).

As a result, current flows more easily throughout the fuel electrode, and the resulting deterioration of the three-phase interface is suppressed.

In addition, in the SOEC according to another embodiment of the present invention, the fuel electrode contains, in addition to the metal or the oxide of the metal, an oxide containing compound A, that is, an alkaline earth metal element and/or a rare earth element other than Sc and Y. The ratio of alkaline earth metal elements and/or rare earth elements excluding Sc and Y to the metal is 1.0% or more in terms of molar ratio. Such a compound A has a strong affinity for _CO2 . Therefore, during the electrolytic treatment of SOEC according to an embodiment of the present invention, the reactive gas CO ₂ is strongly adsorbed on the compound A. Therefore, electrons are smoothly supplied to CO ₂ during the reduction reaction at the fuel electrode.

Here, compound A does not need to have oxide ion conductivity. When compound A does not have oxide ion conductivity, electrolysis proceeds at a three-phase interface formed by the gas phase, the metal contained in the fuel electrode, and the cerium oxide as an intermediate layer. In this case, Compound A existing near the three-phase interface adsorbs and activates CO ₂ , and electrons are smoothly supplied to CO ₂ . As a result, current flows more easily, and deterioration of the reaction field due to this is suppressed.

As a result of the above effects, it is thought that good durability can be obtained in the SOEC according to one embodiment of the present invention.

(SOEC according to one embodiment of the present invention)
Next, the configuration of the SOEC according to an embodiment of the present invention will be described in more detail with reference to the drawings.

FIG. 1 schematically shows a configuration example of a SOEC according to an embodiment of the present invention.

As shown in FIG. 1, a SOEC (hereinafter referred to as "first cell") 100 according to an embodiment of the present invention includes a fuel electrode 110, an oxygen electrode 120, and a space between the fuel electrode 110 and the oxygen electrode 120. and a solid electrolyte layer 130 disposed in the solid electrolyte layer 130 .

The first cell 100 also has a first intermediate layer 150 between the fuel electrode 110 and the solid electrolyte layer 130, and a second intermediate layer between the oxygen electrode 120 and the solid electrolyte layer 130. It has 160.

The first intermediate layer 150 and the second intermediate layer 160 are provided to suppress solid phase reactions between the respective electrodes 110 and 120 and the solid electrolyte layer 130. In particular, by installing the first intermediate layer 150, a more suitable three-phase interface is formed by the intermediate layer 150, the metal (for example, Ni) contained in the fuel electrode 110, and the gas phase, and the fuel electrode 110 is Electrolysis proceeds even if it is not included.

However, the second intermediate layer 160 may be omitted.

When the first cell 100 is connected to the external power source 170, the following reaction occurs at the fuel electrode 110, for example:

2H ₂ O+4e ^- →2H ₂ +2O ^2- (1) formula 2CO ₂ +4e ^- →2CO+2O ^2- (2) formula
Oxide ions generated at the fuel electrode 110 pass through the solid electrolyte layer 130 and reach the oxygen electrode 120 on the opposite side.

For example, the following reaction occurs at the oxygen electrode 120:

2O ^2- →O ₂ +4e ^- Formula (3)
Therefore, by continuing the reactions of formulas (1) to (3), fuel such as hydrogen and/or carbon monoxide can be obtained from the fuel electrode 110.

Here, in the first cell 100, the fuel electrode 110 includes a metal or a metal oxide and a compound A. Further, as described above, compound A includes a mayenite type compound and/or a CaTiO ₃ -based perovskite type compound.

Therefore, in the first cell 100, changes in operating voltage can be suppressed during electrolysis.

(About each component)
Next, each member constituting the SOEC according to an embodiment of the present invention will be described in more detail. In the following description, for clarity, the constituent members will be explained using the first cell shown in FIG. 1 as an example. Therefore, when representing each member, the reference numerals shown in FIG. 1 will be used.

(Fuel electrode 110)
The fuel electrode 110 has the role of electrolyzing water vapor and/or carbon dioxide at an operating temperature.

As described above, the fuel electrode 110 includes metal and compound A. The fuel electrode 110 may be composed of a binder resin such as a green sheet, a powder of compound A, and a powder of a metal or a metal compound, and is a substrate formed by sintering these powders. Good too. If it is a substrate, it can be used as a fuel electrode support type SOEC using the substrate as a support. Further, the fuel electrode may be laminated on a porous support made of metal, ceramics, or a composite thereof.

The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). .

The metal is contained in a volume ratio of 40 vol % to 80 vol % in the entire fuel electrode 110 in terms of metal.

Note that the metal may be provided in a metal oxide state as well as a metal state. This is because during the electrolysis of the first SOEC 100, the metal oxide is reduced to a metallic state.

When the fuel electrode 110 contains a metal oxide, the oxide is contained in a volume ratio of 40 vol % to 80 vol % based on the metal equivalent of the entire fuel electrode 110 .

Moreover, the compound A contained in the fuel electrode 110 includes a mayenite type compound and/or a CaTiO ₃ -based perovskite type compound.

When compound A contains a mayenite-type compound, the mayenite-type compound is a _{12CaO.7Al2O3 -} based mayenite-type compound, a _{12SrO.7Al2O3 -} based mayenite-type compound, or a _12MgO.7Al2O3 -based mayenite- _type compound. There may be.

Moreover, when compound A contains a mayenite type compound, compound A may further contain another compound B.

Such other compounds B include lithium (Li), sodium (Na), potassium (K), barium (Ba), magnesium (Mg), strontium (Sr), titanium (Ti), yttrium (Y), cerium (Ce), lanthanum (La), and neodymium (Nd).

Further, a part of element X may be introduced into the lattice sites of the mayenite-type compound.

Element X may be contained in the range of 0.1 mol% to 30 mol% in terms of oxide based on the entire compound A.

On the _other hand, when Compound _A contains a perovskite type compound, _the perovskite type compound is _{not particularly limited} . ) (here, 0≦x≦1), lanthanum-strontium-gallium-based oxide (La _1-x Sr _x GaO ₃ ) (here, 0≦x≦1), lanthanum-barium-gallium-based oxide ( In addition to La _{1-x Bax} GaO ₃ ) (where 0≦x≦1) and solid solutions and/or mixtures based thereon, compounds that function as electrolytes can be applied. From the viewpoint of affinity with CO ₂ , CaTiO ₃ , SrTiO ₃ , BaTiO ₃ , and solid solutions and/or mixtures based on these are preferred, and CaTiO ₃ and solid solutions and/or mixtures based on these are particularly preferred. .

Further, when the perovskite compound is CaTiO ₃ , a portion of Ca and/or Ti sites may be each substituted with another cation. For example, in a CaTiO ₃ -based perovskite compound, some Ti sites may be replaced with Al.

Moreover, compound A may further contain another compound C.

Such another compound C may include a compound of aluminum (Al). In this case, Al may be contained in the range of 0.1 mol % to 30 mol % based on the entire compound A in terms of oxide.

Furthermore, in one embodiment of the present invention, the compound A contained in the fuel electrode 110 may further include a cerium-based oxide.

Such cerium-based oxides include cerium oxide, cerium oxide doped with rare earth elements such as gadolinium (Gd) or samarium (Sm), and alkaline earth metal elements. The doping amount of rare earth elements such as gadolinium or samarium or alkaline earth metal elements is, for example, in the range of 0 to 20 mol %.

Further, the compound A may include an oxide containing an alkaline earth metal element and/or a rare earth element other than Sc and Y. In this case, the ratio of the alkaline earth metal element and/or the rare earth element other than Sc and Y to the metal is 1.0% or more in terms of molar ratio. The compound A preferably contains an alkaline earth metal element, more preferably contains Al, and is particularly preferably a mayenite type compound. By satisfying such requirements, the adsorption and desorption properties of CO ₂ in Compound A are optimized, electrons are smoothly supplied to CO ₂ , and deterioration is suppressed.

(Oxygen electrode 120)
The oxygen electrode 120 is made of a material that can remove electrons from oxide ions and generate gaseous oxygen molecules.

For the oxygen electrode 120, conventionally known materials may be used. For example, the oxygen electrode 120 is made of lanthanum-strontium-cobalt-based oxide (La _1-x Sr _x CoO ₃ ) (where 0≦x≦1), lanthanum-strontium-cobalt-iron-based oxide (La _{1- x} Sr _x Co _1-y Fe _y O ₃ ) (here, 0≦x≦1, 0≦y≦1), lanthanum-strontium-manganese oxide (La _1-x Sr _x MnO ₃ ) (here, , 0≦x≦1), ceria-based oxides, and mixtures thereof. In particular, it is preferable to include a perovskite oxide containing two or more elements selected from the group consisting of La, Sr, Co, Fe, and Mn. In the case of a fuel electrode supporting type, after forming the solid electrolyte layer, a paste containing powder for the oxygen electrode may be applied and fired to form the oxygen electrode. In the case of a solid electrolyte layer supporting type, the oxygen electrode may be formed by applying a paste containing powder for an oxygen electrode onto the solid electrolyte substrate and baking the paste. A ceria-based electrolyte may be formed as a reaction prevention layer between the solid electrolyte layer and the oxygen electrode.

(Solid electrolyte layer 130)
The solid electrolyte layer 130 is made of a material that has oxide ion conductivity at operating temperatures.

For the solid electrolyte layer 130, conventionally known materials may be used. For example, yttria-stabilized zirconia (YSZ), scandia-stabilized zirconia (ScSZ), lanthanum-strontium-gallium-magnesium oxide (La _1-x Sr _x Ga _1-y Fe _y O ₃ ) (where 0≦ x≦1, 0≦y≦1). In addition, any material other than the above compounds can be used as long as it has oxide ion conductivity.

(First intermediate layer 150 and second intermediate layer 160)
First intermediate layer 150 is arranged between fuel electrode 110 and solid electrolyte layer 130. Further, the second intermediate layer 160 is arranged between the oxygen electrode 120 and the solid electrolyte layer 130.

By installing the first intermediate layer 150, the solid phase reaction between the fuel electrode 110 and the solid electrolyte layer 130 can be suppressed, and deterioration of the solid electrolyte layer 130 and the fuel electrode 110 can be prevented.

The same applies to the second intermediate layer 160.

The first and second intermediate layers 150 and 160 are made of, for example, an oxide containing cerium. Oxides containing cerium are preferred because they have excellent ionic conductivity.

The cerium-containing oxide may be, for example, cerium oxide doped with a rare earth element such as gadolinium (Gd) or samarium (Sm), or an alkaline earth metal element. The doping amount of rare earth elements such as Gd or samarium or alkaline earth metal elements is, for example, in the range of 0 to 20 mol %.

The first cell and its constituent members have been described above. However, it should be noted that the SOEC according to an embodiment of the present invention may be of any type, such as an electrolyte layer supported type, a fuel electrode supported type, or a porous substrate supported type.

(SOEC system)
A SOEC according to an embodiment of the present invention is used as an SOEC system including a stack configured by laminating a plurality of SOECs and a module combining a plurality of these stacks.

FIG. 2 schematically shows an example of the configuration of such a SOEC system.

As shown in FIG. 2, the SOEC system 201 includes a SOEC module 210, a power supply device 220, a gas supply device 230, a gas separation device 240, and a storage device 250.

The SOEC module 210 is constructed by stacking multiple SOECs in series. The power supply device 220 has a role of supplying necessary power to the SOEC module 210. The gas supply device 230 has the role of supplying a reactive gas such as water vapor and/or carbon dioxide to the SOEC module 210. The gas separation device 240 has a role of separating the generated gas generated in the SOEC module 210. The storage device 250 has a role of storing hydrogen and/or carbon monoxide separated by the gas separation device 240.

When the SOEC system 201 is in operation, the SOEC module 210 is heated to the operating temperature by power from the power supply device 220. The operating temperature is 700°C or higher, for example in the range of 700°C to 900°C.

Next, a reaction gas is supplied from the gas supply device 230 to the high temperature SOEC module 210. The reaction gas includes water vapor and/or carbon dioxide. The reaction gas is supplied to the fuel electrode side of each SOEC that constitutes the SOEC module 210.

Next, an electrolysis voltage is applied from the power supply device 220 to the SOEC module 210, and electrolysis is started in the SOEC module 210.

Electrolytic gas is generated in each SOEC included in the SOEC module 210 by electrolysis. That is, hydrogen and/or carbon monoxide is produced from the fuel electrode, and oxygen is produced from the oxygen electrode.

Hydrogen and/or carbon monoxide generated at the fuel electrode is separated by a gas separation device 240. Furthermore, hydrogen and/or carbon monoxide separated by the gas separation device 240 is stored in a storage device 250.

Note that the oxygen generated at the oxygen electrode may be recovered and stored by another device.

Here, in the SOEC system 201, each SOEC configuring the SOEC module 210 uses a SOEC according to an embodiment of the present invention.

Therefore, in the SOEC system 201, changes in the operating voltage can be suppressed.

(Method for manufacturing SOEC according to an embodiment of the present invention)
Next, with reference to FIG. 3, an example of a method for manufacturing an SOEC according to an embodiment of the present invention will be described.

FIG. 3 schematically shows a flow of a SOEC manufacturing method according to an embodiment of the present invention.

As shown in FIG. 3, the SOEC manufacturing method (hereinafter referred to as "first method") according to one embodiment of the present invention is as follows:
(1) a step of installing a first intermediate layer on the first surface of the electrolyte layer (step S110);
(2) a step of installing a fuel electrode on the first intermediate layer (step S120);
(3) installing an oxygen electrode on the side of the electrolyte layer opposite to the first intermediate layer (step S130);
has.

Hereinafter, each process will be explained using the electrolyte layer supported type as an example. Note that, in the following description, for clarity, a manufacturing method thereof will be explained using the above-described first cell 100 as an example. Therefore, when representing each member, the reference numerals shown in FIG. 1 will be used.

(Step S110)
First, a solid electrolyte layer 130 having a first surface and a second surface facing each other is prepared.

The shape of the solid electrolyte layer 130 is not particularly limited, and the solid electrolyte layer 130 may be plate-shaped or disc-shaped.

The solid electrolyte layer 130 may be made of YSZ or ScSZ, as described above.

Next, a first intermediate layer 150 is formed on the first surface of the solid electrolyte layer 130. Further, if necessary, a second intermediate layer 160 may be formed on the second surface of the solid electrolyte layer 130.

The first intermediate layer 150 is formed as follows.

A first intermediate layer paste is installed on the first surface of the solid electrolyte layer 130. The first intermediate layer paste includes, for example, a solvent, cerium-based oxide particles, and a binder. The cerium-based oxide may be Gd-doped cerium oxide.

The method of installing the first intermediate layer paste is not particularly limited. The first intermediate layer paste may be applied to the first surface of the solid electrolyte layer 130, for example, by brush coating, screen printing, or the like.

Thereafter, the first intermediate layer paste is dried and further subjected to a firing process. The firing temperature is, for example, in the range of 1200°C to 1400°C. As a result, the first intermediate layer 150 is formed.

If necessary, the second intermediate layer 160 is also formed in a similar manner.

(Step S120)
Next, the fuel electrode 110 is formed on the first intermediate layer 150.

The fuel electrode 110 is formed as follows.

First, a fuel electrode paste is placed on the surface of the first intermediate layer 150. The fuel electrode paste includes, for example, a solvent, mixed particles, and a binder.

For example, α-terpineol and polyethylene glycol (PEG) can be used as the solvent.

Polyvinyl butyral (PVB), ethyl cellulose (EC), etc. can be used as the binder.

The mixed particles contain a metal or a metal oxide and a compound A.

The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). .

The ratio of the metal or metal oxide to the entire mixed particles is in the range of 40 vol% to 80 vol% in terms of metal volume ratio.

Further, compound A includes a mayenite type compound and/or a CaTiO ₃ -based perovskite type compound.

In particular, the mayenite-type compound may be a 12CaO.7Al ₂ O ₃ -based mayenite-type compound, a 12SrO.7Al ₂ O ₃ -based mayenite-type compound, or a 12MgO.7Al ₂ O ₃ -based mayenite-type compound.

Moreover, compound A may have a mayenite type compound and another compound B. Here, another compound B is lithium (Li), sodium (Na), potassium (K), barium (Ba), magnesium (Mg), strontium (Sr), titanium (Ti), yttrium (Y), cerium (Ce), lanthanum (La), and neodymium (Nd). This increases ionic conductivity and/or affinity with CO ₂ and suppresses an increase in electrolytic voltage.

Such another compound B may be added in an amount of 0.1 mol % to 30 mol % based on the entire compound A in terms of oxide.

Alternatively, compound A may include a perovskite-type compound and another compound C.

Such another compound C may include a compound of aluminum (Al), such as aluminum oxide.

Another compound C may be added in an amount of 0.1 mol % to 30 mol % based on the entire compound A in terms of oxide.

Moreover, compound A may further contain a cerium-based oxide. In that case, the content of the cerium-based oxide relative to the compound A is, for example, 80 vol% or less in volume ratio.

The method of installing the fuel electrode paste is not particularly limited. The fuel electrode paste may be applied onto the first intermediate layer 150 by, for example, brushing, screen printing, or the like.

Thereafter, the fuel electrode paste is dried and further subjected to a firing process. The firing temperature varies depending on the mixed particles contained in the fuel electrode paste, but is, for example, in the range of 1100°C to 1300°C.

As a result, the fuel electrode 110 is formed.

(Step S130)
Next, the oxygen electrode 120 is formed on the second surface of the solid electrolyte layer 130 (the second intermediate layer 160, if present; the same applies hereinafter).

The oxygen electrode 120 is formed as follows.

First, an oxygen electrode paste is placed on the second surface of the solid electrolyte layer 130. The oxygen electrode paste includes, for example, a solvent, mixed particles, and a binder.

As the solvent and binder, for example, the solvent and binder used in the above-mentioned fuel electrode paste can be used.

The mixed particles may be composed of materials that constitute conventional oxygen electrodes. The mixed particles may be, for example, lanthanum-strontium-cobalt-based oxide (La _1-z Sr _z CoO ₃ ) (where 0≦z≦1).

The method of installing the oxygen electrode paste is not particularly limited. The oxygen electrode paste may be applied onto the second surface of the solid electrolyte layer 130, for example, by brush coating, screen printing, or the like.

Thereafter, the oxygen electrode paste is dried and further subjected to a firing process. The firing temperature varies depending on the mixed particles contained in the oxygen electrode paste, but is, for example, in the range of 900°C to 1100°C.

As a result, the oxygen electrode 120 is formed.

Through the above steps, a SOEC according to an embodiment of the present invention can be manufactured.

However, the above method is merely an example, and it is clear to those skilled in the art that the SOEC according to one embodiment of the present invention may be manufactured by another method. That is, the SOEC according to an embodiment of the present invention may be manufactured by any method as long as a fuel electrode having the above-described characteristics can be obtained.

Examples of the present invention will be described below. In the following description, Examples 1 to 20 and Examples 31 to 35 are examples, and Examples 21 and 22 are comparative examples.

(Example 1)
SOEC was produced by the following method.

(Formation of first and second intermediate layers)
First, an intermediate layer was formed on each surface of the solid electrolyte layer by the following procedure. A YSZ substrate (manufactured by Tosoh, thickness 500 μm) was used for the solid electrolyte layer.

10 mol% gadolinium-doped ceria (Ce _0.9 Gd _0.1 O ₂ ) powder (GDC standard product for test and research, manufactured by AGC Seimi Chemical) and α-terpineol solvent (manufactured by Fuji Film Wako Pure Chemical Industries) were mixed at 50% A paste-like composition (referred to as "first paste") was prepared by kneading at a mass ratio of: :50.

After applying masking tape to the first surface of the YSZ substrate except for a 12 mm diameter area approximately at the center, the first paste was applied to the first surface of the YSZ substrate.

Next, the YSZ substrate was turned over, and the first paste was also applied to the second surface using the same procedure.

Next, after drying the YSZ substrate at 140°C, the YSZ substrate was heated to 1400°C. As a result, a first intermediate layer with a diameter of 12 mmφ was formed on the first surface of the YSZ substrate, and a second intermediate layer with a diameter of 12 mmφ was formed on the second surface.

(Preparation of compound A)
Calcium carbonate (4.33 g, manufactured by Kojundo Kagaku Kenkyusho) and alpha alumina (2.57 g, manufactured by Kojundo Kagaku Kenkyusho) were each weighed. These were placed in a pot containing 5 mm zirconia balls and 10 cc of isopropanol (manufactured by Sankyo Chemical), and pulverized and mixed for 3 hours using a planetary ball mill method. Next, the mixed powder was dried at 100°C to remove isopropanol. Furthermore, the mixed powder was separated from the zirconia balls using a sieve. The obtained mixed powder was placed in an alumina crucible and calcined at 1200° C. for 5 hours in the air. The obtained sample was ground in an agate mortar to produce 12CaO.7Al ₂ O ₃ mayenite powder as compound A.

(Formation of fuel electrode)
Prepare a mixed powder by mixing nickel oxide (NiO, manufactured by Kojundo Kagaku Kenkyujo) powder and _{12CaO.7Al2O3 mayenite} powder as the above compound A at a volume ratio of 50:50 in terms of Ni metal. did.

A paste-like composition (hereinafter referred to as "second paste") was prepared by adding a solvent (polyethylene glycol PEG400, manufactured by Kokusan Kagaku) to this mixed powder and kneading it.

Next, a masking tape was applied to the first intermediate layer except for a 10 mm diameter area approximately at the center, and then a second paste was applied onto the first intermediate layer. The second paste was then dried at 230°C.

Furthermore, NiO paste (NiO-AFL; manufactured by Kceracell) was applied thereon as a current collecting member. After drying the NiO paste at 140°C, the assembly was fired at 1300°C to form the fuel electrode and current collector member thereon.

(Formation of oxygen electrode)
A paste-like composition (hereinafter referred to as "third paste") was prepared.

The third paste is a paste containing powder with a composition of (La _0.60 Sr _0.40 ) _0.95 (Co _0.20 Fe _0.80 )O ₃ (LSCF-1; manufactured by Fuel Cell Materials). .

After applying masking tape to the second intermediate layer except for a 6 mm diameter area approximately at the center, a third paste was applied onto the second intermediate layer.

Next, after drying the third paste at 140°C, it was further fired at 1060°C. This formed an oxygen electrode.

Through the above steps, SOEC was manufactured.

The obtained SOEC is referred to as "Cell 1".

(Example 2 to Example 4)
A SOEC was produced in the same manner as in Example 1.

However, in these Examples 2 to 4, the composition of the fuel electrode was changed from that in Example 1. In Examples 2 and 3, a mixture of 12CaO.7Al ₂ O ₃ mayenite powder and ceria powder (GDC standard product for test and research, manufactured by AGC Seimi Chemical) was used. In Example 4, when producing mayenite powder, a predetermined amount of TiO ₂ (titanium (IV) oxide, anatase type, manufactured by Fujifilm Wako Pure Chemical Industries) is added, and the molar ratio becomes Ca: (Al + Ti) = 12:14. The amount of Al ₂ O ₃ was adjusted as follows. The other cell configurations are the same as in Example 1.

The obtained SOECs are referred to as "Cell 2" to "Cell 4", respectively.

(Example 21)
A SOEC was produced in the same manner as in Example 1.

However, in this Example 21, the fuel electrode was composed of a mixture of NiO and YSZ. The mixing ratio of NiO and YSZ was 50:50 (volume ratio) in terms of Ni metal. The other cell configurations are the same as in Example 1.

The obtained SOEC is referred to as "cell 21".

Table 1 below summarizes the composition of the fuel electrode in each cell.

(evaluation)
Each cell prepared as described above was operated at 900° C., and changes in operating voltage during electrolysis were measured.

As the measurement device, a single cell evaluation device for solid oxide fuel cells, BEL-SOFC (manufactured by Microtrack Bell Co., Ltd.), was used.

A mixed gas of hydrogen, argon, water vapor, and carbon dioxide (hydrogen: argon: water vapor: carbon dioxide = 10:70:10:10 (volume ratio)) was supplied to the fuel electrode side. The hydrogen feed rate was 10 ml/min, the argon feed rate was 70 ml/min, the water vapor feed rate was 10 ml/min, and the carbon dioxide feed rate was 10 ml/min. On the other hand, pure oxygen was supplied to the oxygen electrode side at a supply rate of 100 ml/min.

The electrolytic current density was 0.1 A/cm ² .

FIG. 4 also shows changes over time in the electrolytic voltage measured in cell 1 and cell 21.

The electrolysis voltage on the vertical axis was a value normalized to the initial voltage V ₀ of each cell.

From FIG. 4, it can be seen that in the cell 21, the electrolytic voltage increases with the operating time. This means that the electrolysis efficiency of the cell is decreasing.

On the other hand, in cell 1, the electrolytic voltage hardly changes with respect to the operating time. From this, it was found that cell 1 allows more stable electrolysis than cell 21.

Table 2 below summarizes the voltage change rates after 10 hours of electrolysis obtained in each cell.

In Table 2, a value of "-" indicates that the voltage after 10 hours of electrolysis was lower than the initial electrolysis voltage V ₀ .

From Table 2, it was found that in Cells 1 to 4, the increase in electrolytic voltage during use was significantly suppressed compared to Cell 21.

(Example 5)
Below, the voltage change rate of a cell having a fuel electrode containing Compound A with a predetermined composition was estimated.

Powder of compound A was prepared in the same manner as in Example 1. When producing mayenite powder, a predetermined amount of LiCO ₃ (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was added to give a 5 mol% Li ₂ O equivalent, so that the molar ratio was (Li + Ca): Al = 12:14. The amount of _CaCO3 was adjusted accordingly. Other manufacturing conditions are the same as in Example 1.

(Example 6 to Example 16)
Powders of various compounds A were prepared in the same manner as in Example 5. However, in Examples 6 to 16, instead of Li ₂ CO ₃ , Na ₂ CO ₃ (manufactured by Kanto Kagaku), K ₂ CO ₃ (manufactured by Fuji Film Wako Pure Chemical), MgO (manufactured by Fuji Film Wako Pure Chemical), SrCO ₃ (manufactured by Fuji Film Wako Pure Chemical), BaCO ₃ (manufactured by Fuji Film Wako Pure Chemical), Y ₂ O ₃ (manufactured by Shin-Etsu Chemical), La ₂ O ₃ (manufactured by Junsei Chemical), CeO ₂ (manufactured by Kanto Chemical) , Nd ₂ O ₃ (manufactured by Shin-Etsu Chemical), and TiO ₂ (manufactured by Kojundo Kagaku) were added. Na ₂ CO ₃ , K ₂ CO ₃ , MgO, SrCO ₃ , and BaCO ₃ were added in an amount of 5 mol % in terms of Na ₂ O, K ₂ O, MgO, SrO, and BaO. Y ₂ O ₃ , La ₂ O ₃ , and Nd ₂ O ₃ were added in an amount of 3 mol % in terms of Y ₂ O ₃ , La ₂ O ₃ , and Nd ₂ O ₃ . CeO ₂ and TiO ₂ were added in amounts of 11 mol % and 14 mol %, respectively, in terms of CeO ₂ and TiO ₂ .

Further, in Examples 6 to 14 and Example 16, the amount of CaCO ₃ was adjusted so that (metal + Ca):Al = 12:14, and in Example 15, the amount of Al ₂ O ₃ was adjusted so that Ca: (Ti + Al) = 12:14. The amount of each was adjusted. Other manufacturing conditions are the same as in Example 1.

(Example 17)
SOEC was produced by the following method.

(Formation of first and second intermediate layers)
First, by the same method as in Example 1, an intermediate layer was formed on each surface of the solid electrolyte layer.

(Preparation of compound A)
First, 3.6807 g of CaCO ₃ powder (manufactured by Kojundo Kagaku Co., Ltd.) as a Ca source, 1.4804 g of TiO ₂ powder (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) as a Ti source, and Al (NO ₃ powder) as an Al source. ) 6.9594 g of _{3.9H 2} O powder (manufactured by Fuji Film Wako Pure Chemical Industries, Ltd.) was prepared.

These powders were then mixed in the presence of a solvent using a planetary ball mill and zirconia balls. 10 g of 2-propanol was used as the solvent. The rotation speed of the planetary ball mill was 300 rpm, and the processing time was 60 minutes.

Next, the obtained mixed powder was kept in the atmosphere at high temperature for 2 hours to dry it. The treatment temperature was 140°C. This yielded a dry mixed powder from which the solvent had been removed.

Next, the dry mixed powder was calcined in the air.

The treatment temperature was 1400°C and the treatment time was 10 hours.

After cooling to room temperature, the obtained treated body was pulverized in a mortar to produce powder of CaTiO ₃ and aluminum oxide as compound A.

(Formation of fuel electrode)
A mixed powder was prepared by mixing nickel oxide (NiO, manufactured by Kojundo Kagaku Kenkyusho) powder and the powder of the above compound A at a volume ratio of 50:50 in terms of Ni metal.

After that, a SOEC was produced in the same manner as in Example 1.

The obtained SOEC is referred to as "cell 17".

(Example 18 to Example 19)
A SOEC was produced in the same manner as in Example 17.

However, in these Examples 18 to 19, the composition of Compound A was changed from that in Example 17.

Specifically, in Example 18, a mixed powder was prepared by mixing strontium carbonate powder, titanium oxide powder, and α-alumina powder, respectively. The amount of Al contained in the mixed powder was 14 mol % in terms of Al ₂ O ₃ .

On the other hand, in Example 19, a mixed powder was prepared by mixing barium carbonate powder, titanium oxide powder, and α-alumina powder, respectively. The amount of Al contained in the mixed powder was 14 mol % in terms of Al ₂ O ₃ .

Other manufacturing conditions are the same as in Example 1.

The obtained SOECs are respectively referred to as "cells 18 to 19."

(Example 20)
A SOEC was produced in the same manner as in Example 1. However, in this example 20, when forming the fuel electrode, nickel oxide powder and _{12CaO.7Al2O3 mayenite} powder as compound A were mixed at a volume ratio of 70:30 in terms of Ni metal, A mixed powder was prepared.

Other manufacturing methods are the same as in Example 1. The obtained SOEC is referred to as "cell 20."

Table 3 below shows the composition of the fuel electrode containing Compound A assumed in each example.

Further, Table 4 below summarizes the estimated cell voltage change rates after 10 hours of electrolysis in each example.

In Table 4, a value of "-" indicates that the voltage after 10 hours of electrolysis was lower than the initial electrolysis voltage V ₀ .

From these results, it was found that in the cells of Examples 5 to 20, the voltage increase was significantly suppressed even after 10 hours of electrolysis.

(Example 22)
A SOEC was produced in the same manner as in Example 1. However, in this Example 22, CSZ (CaO stabilized zirconia, manufactured by Kojundo Kagaku Co., Ltd.) was used as the compound A, the volume ratio of Ni in terms of metal was 75%, and the sintering temperature of the fuel electrode was 1100°C.

(Example 31)
A SOEC was produced in the same manner as in Example 1. However, in this Example 31, the volume ratio of Ni in terms of metal was 75%, and the sintering temperature of the fuel electrode was 1100°C.

(Example 32)
A SOEC was produced in the same manner as in Example 1. However, in this Example 32, the weighed value during the preparation of Compound A was changed so that the final composition was Ca ₃ Al ₂ O ₆ . Further, the volume ratio of Ni in terms of metal was set to 75%, and the sintering temperature of the fuel electrode was set to 1200°C.

(Example 33)
A SOEC was produced in the same manner as in Example 1. However, in this Example 33, the weighing value during the preparation of Compound A was changed so that the final composition was CaAl ₂ O ₄ . Further, the volume ratio of Ni in terms of metal was set to 75%, and the sintering temperature of the fuel electrode was set to 1100°C.

(Example 34)
A SOEC was produced in the same manner as in Example 1. However, in this Example 34, calcium carbonate powder (manufactured by Kojundo Kagaku Kenkyusho) was used as compound A. Further, the volume ratio of Ni in terms of metal was set to 75%, and the sintering temperature of the fuel electrode was set to 1100°C.

(Example 35)
A SOEC was produced in the same manner as in Example 1. However, in this Example 35, La ₂ O ₃ powder (manufactured by Junsei Kagaku) was used as compound A. Further, the volume ratio of Ni in terms of metal was set to 75%, and the sintering temperature of the fuel electrode was set to 1100°C.

(Evaluation of Examples 21 to 22 and 31 to 35)
Each cell produced as described above was evaluated under the following more severe conditions.

Each cell was operated at 800°C, and changes in operating voltage during electrolysis were measured. As the measurement device, a single cell evaluation device for solid oxide fuel cells, BEL-SOFC (manufactured by Microtrack Bell Co., Ltd.), was used.

A mixed gas of hydrogen, argon, water vapor, and carbon dioxide (hydrogen: argon: water vapor: carbon dioxide = 10:70:10:10 (volume ratio)) was supplied to the fuel electrode side. The hydrogen feed rate was 10 ml/min, the argon feed rate was 70 ml/min, the water vapor feed rate was 10 ml/min, and the carbon dioxide feed rate was 10 ml/min. On the other hand, pure oxygen was supplied to the oxygen electrode side at a supply rate of 100 ml/min.

The electrolysis current density was 0.2 A/cm ² and the electrolysis time was 5 to 50 hours. Calculate the deterioration rate (voltage increase rate per unit time, mV h ^-1 ) every 10 hours for cells whose electrolysis time is 10 hours or more, and every 5 hours for cells whose electrolysis time is less than 10 hours, The largest value was taken as the maximum deterioration rate of each cell.

Table 5 below summarizes the composition of the fuel electrode containing Compound A assumed in each example and the evaluation results.

From Table 5, it can be seen that the maximum deterioration rates are smaller in Examples 31 to 35 than in Examples 21 to 22.

In this way, it was confirmed that by using a specific material as Compound A, the durability of the cell was improved.

(One aspect of the present invention)
One embodiment of the present invention will be described below.

(Aspect 1)
A solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
The fuel electrode includes a metal or a metal oxide and a compound A,
The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
The compound A is a solid oxide electrolytic cell containing a mayenite-type compound and/or a perovskite-type compound containing an alkaline earth metal element.

(Aspect 2)
The solid oxide according to aspect 1, wherein the mayenite-type compound is a _{12CaO.7Al2O3 -} based mayenite-type compound, a _{12SrO.7Al2O3 -} based mayenite-type compound, or a _{12MgO.7Al2O3 -} based mayenite-type compound. shaped electrolytic cell.

(Aspect 3)
Compound A is
The mayenite type compound;
with another compound B,
has
The other compound B is lithium (Li), sodium (Na), potassium (K), barium (Ba), magnesium (Mg), strontium (Sr), titanium (Ti), yttrium (Y), cerium (Ce). ), lanthanum (La), and neodymium (Nd),
The solid oxide electrolytic cell according to aspect 2, wherein a part of the element X is introduced into a lattice site of the mayenite compound.

(Aspect 4)
The solid oxide electrolytic cell according to aspect 3, wherein the element X is contained in the compound A in a range of 0.1 mol% to 30 mol% in terms of oxide.

(Aspect 5)
Compound A is
The perovskite compound;
Another compound C,
has
The other compound C includes an aluminum (Al) compound,
5. The solid oxide electrolytic cell according to any one of aspects 1 to 4, wherein a portion of the aluminum is introduced into a lattice site of the perovskite compound.

(Aspect 6)
The solid oxide electrolytic cell according to aspect 5, wherein the Al is contained in the compound A in a range of 0.1 mol% to 30 mol% in terms of oxide.

(Aspect 7)
The solid oxide electrolytic cell according to any one of aspects 1 to 6, wherein the compound A further contains a cerium-based oxide.

(Aspect 8)
The solid oxide electrolytic cell according to aspect 7, wherein the content of the cerium-based oxide with respect to the compound A is 80 vol% or less in volume ratio.

(Aspect 9)
A module including a plurality of solid oxide electrolytic cells,
A module, wherein each solid oxide electrolytic cell is the solid oxide electrolytic cell according to any one of aspects 1 to 8.

(Aspect 10)
A solid oxide electrolytic cell system,
The module according to aspect 9,
a power supply device that supplies power to the module;
a gas supply device that supplies water vapor and/or carbon dioxide to the module;
a gas separation device that separates hydrogen and/or carbon monoxide generated from the module;
a storage device that stores the hydrogen and/or carbon monoxide separated by the gas separation device;
A solid oxide electrolytic cell system with

(Aspect 11)
A solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
The fuel electrode includes a metal or a metal oxide and a compound A,
The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
The compound A contains an oxide containing an alkaline earth metal element and/or a rare earth element other than Sc and Y, and the ratio of the alkaline earth metal element and/or rare earth element other than Sc and Y to the metal is molar. Solid oxide type electrolytic cell with a ratio of 1.0% or more.

(Aspect 12)
A module including a plurality of solid oxide electrolytic cells,
A module, wherein each solid oxide electrolytic cell is the solid oxide electrolytic cell according to aspect 11.

(Aspect 13)
A solid oxide electrolytic cell system,
The module according to aspect 12,
a power supply device that supplies power to the module;
a gas supply device that supplies water vapor and/or carbon dioxide to the module;
a gas separation device that separates hydrogen and/or carbon monoxide generated from the module;
a storage device that stores the hydrogen and/or carbon monoxide separated by the gas separation device;
A solid oxide electrolytic cell system with

This application claims priority based on Japanese Patent Application No. 2022-113531 filed on July 14, 2022, and the entire contents of the same Japanese application are incorporated by reference into this application.

100 First cell (SOEC)
110 Fuel electrode 120 Oxygen electrode 130 Solid electrolyte layer 150 First intermediate layer 160 Second intermediate layer 170 External power supply 201 SOEC system 210 SOEC module 220 Power supply device 230 Gas supply device 240 Gas separation device 250 Storage device

Claims (13)

1. A solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
   further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
   The fuel electrode includes a metal or a metal oxide and a compound A,
   The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
   The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
   The compound A is a solid oxide electrolytic cell containing a mayenite type compound and/or a perovskite type compound containing an alkaline earth metal element.
2. The solid oxide according to claim 1, wherein the mayenite-type compound is a _{12CaO.7Al2O3 -} based mayenite-type compound, a _{12SrO.7Al2O3 -} based mayenite-type compound, or a _{12MgO.7Al2O3 -} based mayenite-type compound. Physical electrolytic cell.
3. Compound A is
   The mayenite type compound;
   with another compound B,
   has
   The other compound B is lithium (Li), sodium (Na), potassium (K), barium (Ba), magnesium (Mg), strontium (Sr), titanium (Ti), yttrium (Y), cerium (Ce). ), lanthanum (La), and neodymium (Nd),
   3. The solid oxide electrolytic cell according to claim 2, wherein a portion of the element X is introduced into a lattice site of the mayenite compound.
4. The solid oxide electrolytic cell according to claim 3, wherein the element X is contained in the compound A in a range of 0.1 mol% to 30 mol% in terms of oxide.
5. Compound A is
   The perovskite compound;
   Another compound C,
   has
   The other compound C includes an aluminum (Al) compound,
   2. The solid oxide electrolytic cell according to claim 1, wherein a portion of the aluminum is introduced into lattice sites of the perovskite compound.
6. The solid oxide electrolytic cell according to claim 5, wherein the Al is contained in the compound A in a range of 0.1 mol% to 30 mol% in terms of oxide.
7. The solid oxide electrolytic cell according to claim 1, wherein the compound A further contains a cerium-based oxide.
8. The solid oxide electrolytic cell according to claim 7, wherein the content of the cerium-based oxide with respect to the compound A is 80 vol% or less in volume ratio.
9. A module including a plurality of solid oxide electrolytic cells,
   A module, wherein each solid oxide electrolytic cell is a solid oxide electrolytic cell according to claim 1.
10. A solid oxide electrolytic cell system,
    A module according to claim 9,
    a power supply device that supplies power to the module;
    a gas supply device that supplies water vapor and/or carbon dioxide to the module;
    a gas separation device that separates hydrogen and/or carbon monoxide generated from the module;
    a storage device that stores the hydrogen and/or carbon monoxide separated by the gas separation device;
    A solid oxide electrolytic cell system with
11. A solid oxide electrolysis cell having a fuel electrode, an oxygen electrode, and a solid electrolyte layer between the fuel electrode and the oxygen electrode,
    further comprising an intermediate layer between the solid electrolyte layer and the fuel electrode, the intermediate layer comprising cerium oxide;
    The fuel electrode includes a metal or a metal oxide and a compound A,
    The ratio of the metal or the oxide of the metal to the entire fuel electrode is in the range of 40 vol% to 80 vol% in terms of metal volume ratio,
    The metal includes at least one selected from the group consisting of nickel (Ni), copper (Cu), silver (Ag), tungsten (W), platinum (Pt), iron (Fe), and tin (Sn). including,
    The compound A contains an oxide containing an alkaline earth metal element and/or a rare earth element other than Sc and Y, and the ratio of the alkaline earth metal element and/or rare earth element other than Sc and Y to the metal is molar. Solid oxide type electrolytic cell with a ratio of 1.0% or more.
12. A module including a plurality of solid oxide electrolytic cells,
    A module, wherein each solid oxide electrolytic cell is a solid oxide electrolytic cell according to claim 11.
13. A solid oxide electrolytic cell system,
    A module according to claim 12,
    a power supply device that supplies power to the module;
    a gas supply device that supplies water vapor and/or carbon dioxide to the module;
    a gas separation device that separates hydrogen and/or carbon monoxide generated from the module;
    a storage device that stores the hydrogen and/or carbon monoxide separated by the gas separation device;
    A solid oxide electrolytic cell system with

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