KR20140038795A - Support coated composite layers of mixed conductor, and manufacturing method of support coated composite layers of mixed conductor - Google Patents

Abstract

The present invention relates to a support body on which composite layers of mixed conductors are coated and a method for manufacturing the support body on which composite layers of mixed conductors are coated. The method includes: a step of forming a support body; a step of forming composite layers of mixed conductors, which are dense layers, on one surface or two surfaces of the support body by coating slurry or paste including conductive composites (a mixture including dual or more phases) on one surface or two surfaces of the support body; and a step of co-sintering the support body on which the composite layers of mixed conductors are formed. By forming composite layers of mixed conductors which are highly-dense layers having sintered density equal to or greater than 70% and have both ionic conductivity and electronic conductivity, the present invention can be widely used as a connection member (separation plate) or an oxygen-permeable separation film for a fuel cell, an electrolytic cell, or an electrochemical device.

Description

Support coated composite layers of mixed conductor, and manufacturing method of support coated composite layers of mixed conductor}

The present invention relates to a method for preparing a support coated with a composite mixed conductive layer and a support coated with a composite mixed conductive layer, and more specifically, to a composite mixed conductive layer having a dense membrane structure having both electron conductivity and ion conductivity. The present invention relates to a support and a method for preparing a support coated with a composite mixed conductive layer.

As a method of producing a dense coating film (several to several tens of micrometers) directly on the surface using a support, there are a gas phase method and a liquid phase method.

Vapor phase methods include electrochemical vapor deposition (EVD), including chemical vapor deposition (CVD, chemical vapor deposition), sputtering, sputtering, ion beam, and electron beam (EB) methods. At least one of these disadvantages is the limitation of expensive manufacturing equipment and starting materials, the difficulty of fabricating thick specimens due to slow film growth rate, insufficient adhesion with substrate, peeling due to residual stress, and limitation of specimen size. Have Therefore, a relatively easy liquid phase method does not require a specially designed device or expensive equipment, and has been proposed as a method that can be used in practice.

In particular, the liquid phase method includes a sol-gel method, a slip casting method, a slurry coating method, a spin coating method, a dipping method, and an electrochemical method. Many methods, such as electrophoretic method and hydrothermal decomposition, are used.

Among these, a method of using a sol or a slurry, such as dipping, spin coating, slurry coating including spray coating, and sol-gel, may cause drying or gelation due to the low green density of the coating layer. As it progresses, large contractions occur. This large shrinkage creates stress between the support and the coating layer, and in the subsequent sintering process this tendency is further developed, eventually leading to cracking of the coating layer or spoiling with the support.

As mentioned by K. Murata and M. Shimotsu, Denki Kagaku, V. 65, No. 1, 1997, etc., in order to suppress the occurrence of such cracking or peeling, the thickness of one coating layer is adjusted to 1 μm or less. It is known to be. That is, in order to obtain a dense coating layer having a thickness of 10 μm in this manner, there is a disadvantage in that at least 10 drying and heat treatment steps must be repeated. As in the experiments of T. Ishihara, J. Am. Ceram. Soc., Vol. 79, No. 4, pp 913-19, 1996, electrochemical, electrophoretic, and hydrothermal synthesis methods are used to select substrates. There is also a disadvantage that there is a limit to the use of a material having a sufficiently large electrical conductivity.

Prior art related to this is Korean Patent No. 10-0803085 (2008.02.18) "Method of manufacturing a metal connection material for a solid oxide fuel cell".

An object of the present invention can be thinned, and applied to an electrochemical device, an electrolytic cell, a fuel cell fuel electrode, an air electrode, a connecting material (separator), a separator, and the like to improve performance, maintain a small electric resistance, and maintain electrical conductivity and ions. It is to provide a method of manufacturing a support having a composite mixed conductive layer of dense film structure having a conductivity at the same time and a support coated with a composite mixed conductive layer.

According to a feature of the present invention for achieving the object as described above, the present invention is a slurry comprising the steps of forming a support, the conductive composite (mixture composed of dual-phase or more) powder on one or both sides of the support Or coating a paste to form a composite layer of mixed conductor that is a dense film on one or both surfaces of the support, and co-sintering the support on which the composite mixed conductive layer is formed.

The forming of the support may include forming a pre-sintered support by molding and heat-treating a support powder including a binder and a pore-forming agent.

The forming of the support may be performed by mixing a binder and a pore-forming agent with a support powder including at least one of nickel metal and nickel oxide and an YSZ component, followed by molding and heat treatment at 600 to 1600 ° C. Formed of porous support.

Here, YSZ is yttria stabilized zirconia, and yttrium (Y) is doped in the range of 2 mol% to 20 mol% of zirconium oxide (ZrO ₂ ).

At least one of the nickel metal and nickel oxide (NiO) and the YSZ component are mixed in a weight ratio of 3: 7 to 7: 3.

Here, YSZ is yttria stabilized zirconia, and yttrium (Y) is doped in the range of 2 mol% to 20 mol% of zirconium oxide (ZrO ₂ ).

The forming of the support may include one or more powders of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), and chromium oxide (Cr ₂ O ₃ ), One or more powders of zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxides, and lanthanum strontium gallium magnesia oxide After mixing with a binder, a pore-forming agent, it shape | molds and heat-processes at 600-1600 degreeC, and forms it as a plasticized porous support body.

The forming of the support is an ABO ₃ perovskite structural compound, where A is a lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y ) Occupy one or more kinds, and in place B, manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu) , Conductive ceramic powders occupied by at least one of bismuth (Bi), zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerium doped with rare earth or alkali (earth) metal oxides One or more types of electrolyte powder, a binder, and a pore-forming agent in the late compound and the lanthanum strontium gallium magnesia-based oxide are mixed, and then molded and heat-treated at 600 to 1600 ° C to form a sintered porous support.

The forming of the support may include A ₂ BO ₄ perovskite structural compound, and in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y), praseodymium (Pr), neodymium (Nd) occupy one or more kinds, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium ( Conductive ceramic powders occupied by at least one of Ti), nickel (Ni), copper (Cu) and bismuth (Bi), and zirconia, rare earth or alkali (earth) metal oxides doped with rare earth or alkali (earth) metal oxides. Doped ceria, bismuth oxide, barium strontium cerate compound, lanthanum strontium gallium magnesia oxide, at least one electrolyte powder, a binder and a pore-forming agent are mixed, and then molded and heat treated at 600 to 1600 ° C. Thereby forming a sintered porous support.

The forming of the support may be performed after mixing at least one of zirconia-based oxides, alumina oxides, mullite oxides, silica-like oxides, carbides, and nitrides with an organic binder, a solvent, and a pore-forming agent, and then molding 600 By heat treatment at ˜1600 ° C., a sintered porous support is formed.

The support is flat, tubular or a mixture thereof.

The forming of the composite mixed conductive layer may include slurry coating, dipping, spray coating, spin coating, screen printing, and tape casting of a slurry or paste including conductive composite powder, a solvent, and a binder on one or both surfaces of the support. It is formed by coating and heat treatment in one way.

The conductive composite powder is an ABO ₃ perovskite structural compound, in which A is selected from lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y). It occupies more than one species, and in place of B, manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu), bismuth ( Bi) Conductive ceramic powders occupied by at least one of them, zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxides, One or more electrolyte powders of the lanthanum strontium gallium magnesia oxide are mixed.

The conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of 90:10 to 20:80.

The conductive composite powder is an A ₂ BO ₄ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y) , At least one of praseodymium (Pr) and neodymium (Nd), manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), Conductive ceramic powder occupied by at least one of nickel (Ni), copper (Cu) and bismuth (Bi), and ceria doped with zirconia, rare earth or alkali (earth) metal oxides doped with rare earth or alkali (earth) metal oxides At least one electrolyte powder of a bismuth oxide, a barium strontium cerate compound, and a lanthanum strontium gallium magnesia oxide.

The conductive ceramic powder and the electrolyte powder are mixed at a weight ratio of 90:10 to 10:90.

The conductive composite powder is one containing LCCC and YSZ components in a weight ratio of 90:10 to 20:80.

Where LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),

YSZ is yttria stabilized zirconia and is doped with zirconium oxide (ZrO ₂ ) in the range of 2 mol% to 20 mol% of yttrium (Y).

The slurry or paste further includes a sintering aid.

The sintering aid is titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ), bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), neobiium oxide (Nb ₂ O ₃ ) That's it.

The composite mixed conductive layer is adjusted to a thickness by repeatedly coating a slurry or paste containing a conductive composite powder on one or both surfaces of the support.

The thickness of the composite mixed conductive layer is 0.1 ~ 900㎛.

The sintered density of the composite mixed conductive layer is 70% or more and 100% or less.

Prior to forming the composite mixed conductive layer on one or both surfaces of the support, a step of forming a functional layer constituting the anode or the cathode on one or both surfaces of the support is performed in advance.

Prior to forming the composite mixed conductive layer on one or both surfaces of the support, a functional layer is formed on one or both surfaces of the support to solve the difference in thermal expansion rate or sinter shrinkage between the support and the composite mixed conductive layer. The steps are performed in advance.

Before forming the composite mixed conductive layer on one or both surfaces of the support, the gradient functional layer or the gradient functional layer having a multi-layered structure formed by changing the composition between the support and the composite mixed conductive layer little by little on one or both surfaces of the support. The step of forming a line is performed.

After co-sintering the support on which the composite mixed conductive layer is formed, the method may further include forming a catalyst layer constituting an anode or a cathode on the composite mixed conductive layer.

A dense membrane containing a porous support including a conductive support powder component and a conductive composite (mixture composed of dual-phase or more) powder components formed on one or both surfaces of the support and having an electron conductivity and an ion conductivity. Contains composite layers of mixed conductors.

The support powder includes at least one of nickel metal and nickel oxide and an YSZ component.

The support powder is at least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), chromium oxide (Cr ₂ O ₃ ), and rare earth or alkali ( Earth) metal oxide-doped zirconia, rare earth or alkali (earth) metal oxide-doped ceria, bismuth oxide, barium strontium cerate compound, and lanthanum strontium gallium magnesia-based oxide.

The support powder is at least one of zirconia-based oxide, alumina oxide, mullite oxide, silicate oxide, carbide and nitride.

The support powder or the conductive composite powder is an ABO ₃ perovskite structural compound, and in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium ( At least one type of Y) is occupied and B is manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), and copper (Cu). ), Conductive ceramic powders occupied by at least one of bismuth (Bi) and ceria, bismuth oxide, barium strontium doped with zirconia, rare earth or alkali (earth) metal oxides doped with rare earth or alkali (earth) metal oxides. And at least one electrolyte powder of a cerate compound and a lanthanumstrolium gallium magnesia oxide.

The support powder or the conductive composite powder is an A ₂ BO ₄ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), At least one of yttrium (Y), praseodymium (Pr), and neodymium (Nd) occupies manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), and titanium. Conductive ceramic powders occupied by at least one of (Ti), nickel (Ni), copper (Cu) and bismuth (Bi);

At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide Powder.

The conductive composite powder includes a conductive ceramic powder and an electrolyte powder in a weight ratio of 90:10 to 10:90.

The conductive composite powder is one containing LCCC and YSZ components in a weight ratio of 90:10 to 10:90.

Where LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),

YSZ is yttria stabilized zirconia and is doped with zirconium oxide (ZrO ₂ ) in the range of 2 mol% to 20 mol% of yttrium (Y).

The composite mixed conductive layer has a sintered density of 70% or more and 100% or less.

The composite mixed conductive layer has a thickness of 0.1 ~ 900㎛.

The support is flat, tubular or a mixture thereof.

The support or the support on which the composite mixed conductive layer is formed is used as any one of a fuel electrode, an air electrode, a separator (Separator), and a membrane in any one or more of a fuel cell, an electrolysis cell, and an electrochemical device.

A functional layer constituting a fuel electrode or an air electrode is formed between the support and the composite mixed conductive layer.

A catalyst layer constituting the anode or the cathode is formed on the composite mixed conductive layer.

According to the present invention, a composite mixed conductive layer that is a dense membrane having ion conductivity and electron conductivity is formed on a support.

The composite mixed conductive layer is a dense membrane with a high sintered density of 70% or more and has high electrical conductivity. Therefore, the composite mixed conductive layer can be widely used for connecting materials (separation plates) or oxygen permeable membranes in any one or more of fuel cells, electrolytic cells, and electrochemical devices. Corrosion does not occur during operation, thereby improving the performance of fuel cells, electrolytic cells, and electrochemical devices.

In addition, the composite mixed conductive layer of the present invention has an electron conductivity and an ion conductivity, so that the composite mixed conductive layer can penetrate and produce oxygen or hydrogen.

In addition, the composite mixed conductive layer of the present invention maintains a small electric resistance even after a long time operation (after 48 hours) and a stable voltage so that the operation of fuel cells, electrolytic cells, and electrochemical devices can be stably maintained. It works.

1 is a view showing the layer structure of the support coated with a composite mixed conductive layer.
Figure 2 is a table showing the sintered density, microstructure, electrical resistance value according to the weight ratio of the conductive composite powder (LCCC-YSZ).
3 is a cross-sectional microstructure photograph of a porous LCCC layer (monocomponent) formed on a support as a comparative experimental example.
Figure 4 is a cross-sectional microstructure photograph taken after 24 hours operation of the porous LCCC layer as a comparative experimental example.
According to FIG. 4, a microstructure in which severe corrosion occurred in the porous LCCC layer after 24 hours of operation was confirmed.
5 is a cross-sectional microstructure photograph taken after 24 hours of operation of the composite mixed conductive layer (LCCC-YSZ) prepared by the present invention.
Figure 6 is a graph measuring the voltage according to the long-term performance test (hydrogen / air) of the composite mixed conductive layer (LCCC-YSZ) prepared by the present invention.
7 is a graph measuring the electrical resistance (after 48 hours of operation) of the composite mixed conductive layer ((LCCC-YSZ)) prepared by the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The support coated with the composite mixed conductive layer of the present invention is formed on one or both surfaces of the support 10 and the support 10 containing a conductive support powder component, as shown in FIG. And a composite layer of mixed conductor 20 containing a conductive component (mixture composed of dual-phase or more) powder having an electron conductivity and an ion conductivity.

The support may be used in any one of an electrochemical device, an electrolytic cell, a fuel electrode, an air electrode, a separator (Separator), and a membrane applied to a fuel cell. The support is a porous support. The support may be flat, tubular or a mixture thereof.

When the electron conductivity is high, it may be used as an oxygen permeation membrane or a hydrogen permeation membrane. The composite mixed conductive layer has electron conductivity and ion conductivity, so that it can be produced by permeating oxygen or hydrogen.

The composite mixed conductive layer is a dense film that can operate at low temperatures. The conductive composite powder promotes sintering to form a dense film. The dense film refers to a film having a sintered density of 70% or more and 100% or less. Preferably, it refers to a film having a sintered density of 80% or more and 100% or less.

The composite mixed conductive layer has a sintered density of 70% or more and 100% or less, preferably 80% or more and 100% or less.

The composite mixed conductive layer maintains a small electrical resistance of 0.10 m 2 or less. Preferably, the composite mixed conductive layer maintains a small electrical resistance of 0.035 m 2 or less.

If the electrical resistance is higher than 0.035Ω㎠, the electron conductivity is bad, but it can be used as oxygen permeation membrane or hydrogen permeation membrane. In addition, when the electrical resistance is higher than 0.10 전자 cm 2, the electron conductivity is lost, and thus it cannot be used as an oxygen permeable membrane or a hydrogen permeable membrane.

The composite mixed conductive layer is a thin film having a thickness in the range of 0.1 to 900 µm.

The support on which the composite mixed conductive layer is formed is used in a high performance solid oxide electrolysis cell (SoFC), a solid oxide fuel cell (SOFC), and a direct carbon fuel cell (DCFC) operating at low temperature. It can be used as a separator that is an electrically conductive ceramic connecting material.

In addition, the support on which the composite mixed conductive layer is formed may be used to produce high concentrations of oxygen required by a pure oxygen combustion boiler (Oxy-PC) or coal gasification combined cycle (IGCC) for carbon dioxide reduction and high efficiency power generation.

In addition, the support on which the composite mixed conductive layer is formed may be used for hydrogen production in addition to oxygen during steam decomposition as a renewable energy source.

In addition, the support on which the composite mixed conductive layer is formed may be used in a technique for manufacturing a membrane separator (ITM, Ion Transport Membrane or OTM, Oxygen Transport Membrane) which is used as a very important separator in oxygen (nitrogen) and hydrogen separation processes. .

As described above, the support having the composite mixed conductive layer is formed on one or both surfaces of the porous support to form a composite mixed conductive layer having a thin thickness and a dense membrane to improve the performance of the connecting member (separator plate) or to improve the performance as the separator.

The conductive support powder may be a mixture of at least one of nickel metal and nickel oxide and an YSZ component.

In addition, the conductive support powder is at least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), chromium oxide (Cr ₂ O ₃ ), Zirconia doped with rare earth or alkali (earth) metal oxide as an additive, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide as an additive, lanthanum strontium gallium magnesia oxide It may be a mixture of one or more powders.

In addition, the conductive support powder is an ABO ₃ perovskite structural compound, and in the A site, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm) and yttrium (Y ) Occupy one or more kinds, and in place B, manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu) , Conductive ceramic powders occupied by at least one of bismuth (Bi), zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerium doped with rare earth or alkali (earth) metal oxides It may be a mixture of one or more electrolyte powders of a late compound and a lanthanum strontium gallium magnesia oxide.

In addition, the conductive support powder is an A ₂ BO ₄ perovskite structural compound, and in the A site, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y), praseodymium (Pr), neodymium (Nd) occupy one or more kinds, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium ( Conductive ceramic powders occupied by at least one of Ti), nickel (Ni), copper (Cu) and bismuth (Bi), and zirconia, rare earth or alkali (earth) metal oxides doped with rare earth or alkali (earth) metal oxides. Doped ceria, bismuth oxide, barium strontium cerate compound, lanthanum strontium gallium magnesia-based oxide may be a mixture of at least one electrolyte powder.

In addition, the support powder may be non-conductive.

The support powder is at least one of zirconia-based oxides, alumina oxides, mullite oxides, silicate oxides, carbides and nitrides. When the support coated with the composite mixed conductive layer is used for the oxygen permeation membrane, a support powder having no conductivity is used.

The conductive composite powder is a mixture of conductive ceramic powder and electrolyte powder in a weight ratio of 90:10 to 10:90. Preferably, the conductive composite powder is a mixture of conductive ceramic powder and electrolyte powder in a weight ratio of 90:10 to 20:80.

In addition, the conductive composite powder is LCCC and YSZ components are mixed in a weight ratio of 90:10 to 10:90, Preferably, the conductive composite powder is LCCC and YSZ components are mixed in a weight ratio of 90:10 ~ 20:80 Can be.

LCCC is a material exclusively for electron conduction, and YSZ is a material dedicated to conduction of oxygen ions, and each of them is added to a different phase to cause electron conduction and oxygen conduction, which are the core reactions necessary for oxygen permeation separation, to occur in the dedicated material. .

When the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of less than 90:10, the sintered density of the composite mixed conductive layer is lower than 80%, thus resulting in lack of compactness, which is a feature of the present invention, and the conductive ceramic powder and the electrolyte powder exceed 20:80. When mixed at a weight ratio of, the sintered density is increased, but the electrical resistance is increased, resulting in low electronic conductivity.

In addition, when the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of more than 10:90, the sintered density is increased, but the electrical resistance is rapidly increased, and the electronic conductivity is lost.

When the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio range of more than 20:80 and less than 10:90, the electrical resistance is higher than 0.035 kcm 2, resulting in poor electronic conductivity, but not higher than 0.10 kcm 2 or more, which causes no electrical conductivity. Therefore, it is included in the scope of the present invention.

However, the most preferable range is that the conductive composite powder, the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of 90:10 to 20:80.

Specifically, the conductive composite powder is an ABO ₃ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y) At least one of them is occupied by B, and manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu), Conductive ceramic powder occupied by at least one of bismuth (Bi), zirconia doped with rare earth or alkaline metal oxide as an additive, ceria, bismuth oxide, barium doped with rare earth or alkali (earth) metal oxide as an additive One or more electrolyte powders of the strontium cerate compound and the lanthanum strontium gallium magnesia oxide may be mixed in a weight ratio of 90:10 to 20:80.

In addition, the conductive composite powder is an A ₂ BO ₄ perovskite structural compound, in place of lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y ), Praseodymium (Pr), and neodymium (Nd) occupy one or more kinds, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti) , Conductive ceramic powder occupied by at least one of nickel (Ni), copper (Cu) and bismuth (Bi), and zirconia doped with rare earth or alkali (earth) metal oxides as additives, rare earth or alkali (earth) metals as additives The oxide-doped ceria, bismuth oxide, barium strontium cerate compound, or lanthanum strontium gallium magnesia-based oxides may be mixed in a weight ratio of at least one electrolyte powder 90:10 to 20:80.

As shown in (b) of FIG. 1, in the support on which the composite mixed conductive layer is coated, a functional layer 30 constituting a fuel electrode or an air electrode is formed between the support 10 and the composite mixed conductive layer 20. Can be.

That is, the functional layer 30 is formed on one side or both sides of the support 10, and the composite mixed conductive layer 20 is formed on the functional layer 30. When the support 10 is used as a connecting material, a separator, a separator, etc., the functional layer 30 becomes a fuel electrode or an air electrode for electrode reaction.

On the other hand, the functional layer may be a functional layer to solve the difference in thermal expansion rate difference or sinter shrinkage between the support and the composite mixed conductive layer.

In addition, the functional layer may be an inclined functional layer or a gradient functional layer formed by changing the composition between the support and the composite mixed conductive layer little by little.

As shown in (c) of FIG. 1, the support having the composite mixed conductive layer coated thereon may further include a catalyst layer 40 constituting the anode or the cathode on the composite mixed conductive layer 20.

That is, the functional layer 30 is formed on one or both surfaces of the support 10, the composite mixed conductive layer 20 is formed on the functional layer 30, and the catalyst layer is formed on the composite mixed conductive layer 20. 40 is further formed. When the anode or the cathode is not disposed on the composite mixed conductive layer 20 and the connection material, the separator, and the separator are positioned, the catalyst layer 40 is further formed as the anode or the cathode for the electrode reaction.

In addition, as shown in (d) of FIG. 1, in the support on which the composite mixed conductive layer is coated, the composite mixed conductive layer 20 is formed on one or both surfaces of the support 10, and the composite mixed conductive layer 20 is provided. The catalyst layer 40 for the electrode reaction may be further formed on the top.

Method for producing a support coated with a composite mixed conductive layer of the present invention. Forming a support and coating a slurry or paste containing a conductive composite (mixture composed of dual-phase or more) powder on one or both surfaces of the support to form a dense film on one or both surfaces of the support. Forming a layer (Composite layers of mixed conductor), and co-sintered the support on which the composite mixed conductive layer is formed.

The support forms a support powder containing a binder and heat treatment to form a plasticized support. During co-sintering, the support is heat-treated in a plasticized state so that there is no difference in shrinkage between the composite mixed conductive layer and the support to form a porous porous support.

Specifically, the support is formed by mixing a binder and a pore-forming agent with a support powder containing at least one of nickel metal and nickel oxide and an YSZ component, followed by molding and heat treatment at 600 to 1600 ° C. It can be formed as.

Here, YSZ is yttria stabilized zirconia, and yttrium (Y) is doped in zirconium oxide (ZrO ₂ ) in a range of 2 mol% to 20 mol%. In the present embodiment, YSZ uses zirconium oxide (ZrO ₂ ) in which yttrium (Y) is doped with 8 mol%.

At least one of nickel metal and nickel oxide (NiO) and YSZ components are mixed in a weight ratio of 3: 7 to 7: 3. Preferably, at least one of nickel metal and nickel oxide (NiO) and the YSZ component are mixed in a weight ratio of 1: 1.

Pore forming agent is added to form the pore may be used graphite, starch powder and the like. In the case of graphite, the particle size and mixing ratio are properly adjusted. The binder is an organic binder. Ethyl alcohol may be further added as a solvent.

The support may be a powder of one or more of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), and chromium oxide (Cr ₂ O ₃ ), and as an additive, rare earth or Zirconia doped with alkali metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali metal oxide as additives, lanthanum strontium gallium magnesia-based oxide, binder, pore forming After mixing the agent, it can be formed into a plastic sintered porous support by molding and heat treatment at 600 ~ 1600 ℃.

In addition, the support is an ABO ₃ perovskite structural compound, and at the A site, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y) The above occupies, and in place of B, manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu), bismuth (Bi) 1) Conductive ceramic powder, zirconia doped with rare earth or alkali metal oxide as an additive, ceria, bismuth oxide, barium strontium cerate compound, lanthanum doped with rare earth or alkali metal oxide as an additive One or more electrolyte powders of the titanium gallium magnesia-based oxide, a binder and a pore-forming agent are mixed, and then molded and heat-treated at 600 to 1600 ° C to form a sintered porous support.

The support may be formed by mixing at least one of zirconia-based oxides, alumina oxides, mullite oxides, silica-based oxides, carbides, and nitrides with an organic binder, a solvent, and a pore-forming agent, followed by molding and heat treatment at 600 to 1600 ° C. As a result, it is possible to form a plasticized porous support.

The support is shaped into a plate, tube or mixture thereof. The plate type is uniaxially formed into a square mold of a desired size to produce a unit cell, and the tube type is extruded by about 1 m in length using an extruder.

The flat plate and tubular supports are dried and dried at room temperature to form a sintered porous support by heat treatment at 600 to 1600 ° C.

The composite mixed conductive layer coats and heat-treats a slurry or paste containing conductive composite powder, solvent, and binder on one or both sides of the support by any one of slurry coating, dipping, spray coating, spin coating, screen printing, and tape casting. To form.

The composite mixed conductive layer adjusts the thickness by repeatedly coating a slurry or paste including the conductive composite powder on one or both surfaces of the support.

The conductive composite powder is a mixture of conductive ceramic powder and electrolyte powder. The conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of 90:10 to 10:90. Preferably, the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of 90:10 to 20:80.

When the conductive ceramic powder and the electrolyte powder are mixed in a weight ratio of less than 90:10, the sintered density of the composite mixed conductive layer is lower than 70%, and thus, denseness is a feature of the present invention, and the conductive ceramic powder and the electrolyte powder are greater than 20:80. When mixed at a weight ratio of S, the sintered density is increased, but the electrical resistance is increased, and the electrical conductivity is lowered. If the mixture is mixed at a weight ratio of more than 10:90, the electrical resistance is rapidly increased to 0.10Ωcm 2 or more, and the electronic conductivity is lost.

Specifically, the conductive composite powder is an ABO ₃ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y) At least one of them is occupied by B, and manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu), Conductive ceramic powder occupied by at least one of bismuth (Bi), zirconia doped with rare earth or alkali metal oxide as an additive, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali metal oxide as an additive, One or more electrolyte powders of the lanthanum strontium gallium magnesia oxide are mixed.

In addition, the conductive composite powder is an A ₂ BO ₄ perovskite structural compound, in place of lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y ), Praseodymium (Pr), and neodymium (Nd) occupy one or more kinds, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti) , Conductive ceramic powder occupied by at least one of nickel (Ni), copper (Cu) and bismuth (Bi), zirconia doped with rare earth or alkali metal oxide as an additive, ceria doped with rare earth or alkali metal oxide as an additive, The bismuth oxide, the barium strontium cerate compound, and the lanthanum strontium gallium magnesia oxide are mixed with at least one electrolyte powder.

The slurry or paste for forming the composite mixing conductive layer further includes a sintering aid. Sintering aid is included to improve the sintering properties of the slurry or paste containing the conductive composite powder to enhance the compaction and sintering density of the composite mixed conductive layer.

Sintering aids include titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ), at least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Can be.

The sintering aid is added in a proportion of 0 to 30% by weight based on the total weight of the slurry or paste. When the sintering aid is added in excess of 30% by weight based on the total weight of the slurry or paste, the electrical conductivity of the composite mixed conductive layer is deteriorated.

For example, the composite mixed conductive layer may be formed by coating and heat treating a slurry including conductive composite powder, a solvent, and a binder on one or both surfaces of the support by a tape casting method.

Specifically, the slurry containing the conductive composite powder, the solvent, and the sintering aid is tape cast to form a green sheet on the release film, and the green sheet to which the release film is attached is attached to one surface of the support, and then a pressure reduction is caused. While the release film is removed from the green sheet attached to one surface of the support, a composite mixed conductive layer may be formed on one surface of the support.

The slurry for forming the green sheet may be mixed in the conductive composite powder with ethyl alcohol and toluene in a ratio of 1: 0.5 to 1, and an organic binder may be used as the binder. In addition, a dispersant may be further included in the slurry.

That is, the slurry for forming the green sheet is first milled after mixing a solvent and a conductive composite powder in which a dispersant is dissolved in a ball mill container, and then organic binder (PVB, Polyvinyly butyral) and a plasticizer (DBP, Dibutyl Phthalate) are added thereto. It is prepared by secondary milling by further addition and mixing.

The slurry is set to have a viscosity in the range of 10 ³ to 10 ⁵ cps, followed by a tape casting process.

Before attaching the green sheet to one surface of the support, a solvent or oil may be applied to the support or the green sheet. The solvent or oil causes the support and the green sheet to be in uniform contact with each other. In addition, the solvent or oil can facilitate the removal of the release film from the green sheet without using a pressure difference when removing the release film.

The release film may be a polyester film having a thickness of 400 μm or less, or a mylar film coated with silicon on one surface thereof. Mylar film (Mylar, electrical insulation material, DuPont, USA) uses a thickness of 40 ~ 400㎛.

The slurry forms a green sheet on the release film by performing a tape casting of a desired thickness in the range of 20 to 2000 μm in the blade height of the doctor blade at a feed rate of 1 to 50 cm / min.

The thickness of the composite mixed conductive layer is adjusted when forming the green sheet, or by repeatedly controlling the attachment of the green sheet to the support. The thickness of the composite mixed conductive layer is 0.1 to 900 µm, and the sintered density is 70% or more and 100% or less. The sintered density should be 70% or more to ensure the compactness of the composite mixed conductive layer. Preferably, the sintered density is 80% or more and 100% or less.

In the process of removing the release film, it is preferable to use a pressure-sensitive adhesive device.

After removing the release film, the support on which the green sheet is attached may be aged. The aging treatment is a homogenization treatment by keeping in an oven at about 70 ° C. for about 1 hour. After the aging treatment, the support on which the green sheet is attached is heat treated at 600 to 1600 ° C to form a composite mixed conductive layer.

Prior to forming the composite mixed conductive layer on one or both surfaces of the support, a step of forming a functional layer constituting the anode or the cathode on one or both surfaces of the support may be performed in advance.

Alternatively, prior to the step of forming the composite mixed conductive layer on one or both surfaces of the support, forming a functional layer for solving the difference in thermal expansion rate or sinter shrinkage between the support and the composite mixed conductive layer on one or both surfaces of the support. Steps can be performed in advance.

Alternatively, before the step of forming the composite mixed conductive layer on one or both sides of the support, a gradient functional layer or a gradient functional layer having a multi-layer structure is formed on the one or both sides of the support by changing the composition between the support and the composite mixed conductive layer little by little. The step may be performed in advance.

After co-sintering the support on which the composite mixed conductive layer is formed, the method may further include forming a catalyst layer constituting the anode or the cathode on the composite mixed conductive layer.

The functional layer may screen-print and heat-treat a slurry containing a mixture of a LCCC and an YSZ component, a solvent, a dispersant, an organic binder, and a plasticizer to one or both surfaces of the support to form a sintered functional layer.

The catalyst layer may be screen-printed and heat-treated a slurry containing a mixture of LCCC and YSZ components, a solvent, a dispersant, an organic binder, and a plasticizer on top of the composite mixed conductive layer to form a sintered catalyst layer. Heat treatment may be heat treatment in the range of 600 ~ 1600 ℃.

Where LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),

YSZ is yttria stabilized zirconia and is doped with zirconium oxide (ZrO ₂ ) in the range of 2 mol% to 20 mol% of yttrium (Y).

The support, the functional layer, the composite mixed conductive layer, and the catalyst layer may be formed into a multi-layered or multi-layered layer using one or more compositions in each of them, while varying the composition and porosity, when the respective layers are prepared.

The composite mixed conductive layer coated with the support prepared by the above-described process has a sintered density of 70% or more and 100% or less, and maintains a small electrical resistance of 0.10Ωcm 2 or less, thereby maintaining an oxygen permeation membrane or a hydrogen permeation membrane. It can be used as.

And, the conductive composite powder for this is the LCCC and YSZ has a weight ratio of 10:90 ~ 90:10.

Hereinafter, the embodiment of the present invention will be described in more detail. However, the examples and the like described below are for illustrating the present invention, and the present invention is not limited thereto and can be variously modified and changed.

< Example  1>

Manufacture of connecting materials for electrolytic cells or fuel cells: tape casting

It manufactures the connection material for the electrolytic cell or fuel cell, and uses the tape casting method to form the composite mixed conductive layer.

First, to prepare a support, nickel oxide (NiO) powder and yttria stabilized zirconia (YSZ) doped with yttrium (Y) in zirconium oxide (ZrO ₂ ) are prepared. For convenience of description, yttria stabilized zirconia (YSZ) doped with yttrium (Y) in zirconium oxide (ZrO ₂ ) may be referred to as 8YSZ.

 The nickel oxide (NiO) powder was ball milled in a planetary mill for 2 hours and then dried in an oven. The 8YSZ powder was calcined in a mortar after being calcined at 1400 ° C. in advance. The nickel oxide (NiO) powder thus prepared and 8YSZ were mixed at a weight ratio of 5: 5, and wet ball milled for 24 hours. In this case, graphite, an organic binder, and ethyl alcohol for pore formation are further added, and after ball milling, a plate, a tube, or a mixture is molded.

After shaping into flat, tubular or mixed form, it is dried in an oven and heat treated to form a sintered porous support. Heat treatment is carried out at 1200 ~ 1450 ℃. The support thus prepared becomes the fuel electrode of the fuel cell.

Next, a functional layer is formed on one side or both sides of the support. The functional layer becomes a fuel electrode functional layer for electrode reaction.

The functional layer screen-prints a slurry containing 8YSZ, a solvent, a dispersant, an organic binder, and a plasticizer on one or both surfaces of the support and is heat-treated at 1200 to 1450 ° C. to form a plasticized functional layer.

Next, a composite mixed conductive layer is formed on the functional layer.

The composite mixed conductive layer was mixed with LCCC and YSZ in a weight ratio of 5: 5, and further ball milled for 24 hours with ethyl alcohol to perform mechanical grinding and mixing. At this time, the sintering aid is further added to improve final sintering characteristics of the composite mixed conductive layer and to increase densification and sintering density. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

Sintering aids include titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ) at least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Add. Sintering aid is added at a ratio of 0 to 30% by weight based on the total weight of the slurry or paste.

Slurry mixed with LCCC, 8YSZ, ethyl alcohol, and sintering aid is produced into a green sheet having a thickness of about 60 μm on a release film through tape casting. At this time, the release film used uses a mylar film of about 80㎛ thickness.

The green sheet to which the mylar film is attached is attached on top of the functional layer of the support, and the mylar film is removed from the green sheet.

Mylar film is attached to the support and the green sheet by using a pressure-sensitive or pressure-sensitive attachment device, and then remove the mylar film from the green sheet.

Alternatively, the solvent or oil is applied to the support or the green sheet to directly attach the support and the green sheet, and then remove the mylar film from the green sheet. The solvent or oil uniformly attaches the support and the green sheet and facilitates the removal of the mylar film. Terpineol is used as a solvent.

After removing the mylar film as described above in order to control the thickness of the composite mixed conductive layer, the green sheet produced through the tape casting is repeatedly attached to the upper part of the first attached green sheet and the mylar film from the green sheet. Remove it.

Alternatively, prior to attaching the green sheet of the composite mixed conductive layer, the green sheet of the functional layer of the anode and the cathode components and, in some cases, the functional layer for adjusting the shrinkage rate or the inclined functional layer slightly changing the composition may be attached as described above. The composite mixed conductive layer including the functional layer of the multi-layer structure is manufactured by the process of.

In this example, the green sheet was attached twice.

Thereafter, the support on which the green sheet is attached is aged. The aging treatment is to homogenize by holding in an oven at about 70 ℃ for about 1 hour.

After the aging treatment, the support with the green sheet is co-sintered at 1400 to 1650 ° C. to prepare a support having a dense composite mixed conductive layer. The thickness of the prepared composite mixed conductive layer is in the range of 10 ~ 30㎛. The support having the composite mixed conductive layer thus prepared is used as a connecting material (separation plate) of the fuel cell.

The support serves as an anode insulator, the functional layer serves as an anode for electrode reaction, and the composite mixed conductive layer serves as an electrolyte membrane as a dense membrane having electron conductivity and ion conductivity.

The green sheet slurry for tape casting was described as mixing LCCC, 8YSZ, ethyl alcohol, and sintering aid.

In addition, the slurry for the green sheet for tape casting may include a solvent, a dispersant, a conductive composite powder, an organic binder, and a plasticizer.

The solvent is used by mixing ethyl alcohol and toluene in a ratio of 1: 0-5.

In order to prepare a slurry for green sheet for tape casting, first, a solvent in which a dispersant is dissolved in a ball mill container is put therein, and then a primary milling is performed by mixing a conductive composite powder of an anode or a cathode. The conductive composite powder is mixed to have a specific surface area of 2 ~ 200㎥ / g for uniform mixing. Next, an organic binder and a plasticizer are further added to the first milled mixture to prepare a second mill.

The prepared green sheet slurry is subjected to a tape casting process after the viscosity is between 10 ³ and 10 ⁵ cps. Green sheet is manufactured by performing a tape casting of the desired thickness in the range of 20 ~ 2000㎛ the height of the blade at a feed rate of 1 to 50cm / min using a silicon-coated mylar film on one side.

The green sheet slurry for tape casting is 10 to 200 g of solvent (mixing ethyl alcohol and toluene in a ratio of 1: 0 to 5) per 100 g of the conductive composite powder, 0.1 to 10 g of a dispersant (fish oil), and 1 to 1 organic binder (PVB). 10 g and 1 to 10 g of plasticizer (DBP) were added.

In this case, the composite mixed conductive layer for preparing the anode support type connection material is mixed with YSZ having a particle size of 0.01 ~ 10㎛ and LCCC powder having a particle size of 0.01 ~ 10㎛ in a weight ratio of 5: 5, and the organic binder It is preferable to manufacture by the green sheet manufactured by further mixing a plasticizer and tape-casting to thickness of 10-600 micrometers. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

The support on which the composite mixture conductive layer was formed by co-sintering was mixed with YSZ having a particle size of 0.01-10 μm and LCCC powder having a particle size of 0.01-10 μm at a weight ratio of 2: 5 on the surface of the composite mixed conductive layer. In addition, the catalyst layer may be further formed by screen printing a slurry or paste in which an organic binder and a plasticizer are further mixed to a thickness of 5 to 600 μm. After the formation of the catalyst layer on the surface of the composite mixed conductive layer may be heat-treated at a temperature of 600 ℃ or more to complete the final support type connecting member (separator).

< Example  2>

Manufacture connection material for electrolytic cell or fuel cell: screen printing method

Prepare a nickel oxide (NiO) powder and yttrium to zirconium oxide (ZrO ₂₎ (Y), this yttria-stabilized zirconia (YSZ) doped with 8 mol% to prepare a support.

 The nickel oxide (NiO) powder was ball milled in a planetary mill for 2 hours and then dried in an oven. The YSZ powder was calcined in a mortar after being calcined at 1400 ° C. in advance. The nickel oxide (NiO) powder and YSZ thus prepared were mixed at a weight ratio of 5: 5, and wet ball milled for 24 hours. In this case, graphite, an organic binder, and ethyl alcohol for pore formation are further added, and after ball milling, a plate, a tube, or a mixture is molded.

In the case of graphite added for pore formation, the particle size and mixing ratio are appropriately adjusted.

Thereafter, the molded product in the form of a plate, a tube, or a mixture is dried at room temperature and heat-treated to form a plasticized porous support. Heat treatment is carried out at 1200 ~ 1450 ℃. The support thus prepared becomes the fuel electrode of the fuel cell.

Next, a functional layer is formed on one side or both sides of the support. The functional layer becomes a fuel electrode functional layer for electrode reaction.

The functional layer screen-prints a slurry containing YSZ, a solvent, a dispersant, an organic binder, and a plasticizer on one or both surfaces of the support and heat-processes at 1250 ° C. to form a plasticized functional layer.

Next, a composite mixed conductive layer is formed on the functional layer.

The composite mixed conductive layer is composed of LCCC having (La _x Ca _{1 -x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1) and YSZ doped with yttrium (Y). Was mixed at a weight ratio of 5: 5, and a solvent and a provider such as isopropyl alcohol were further mixed and ball milled for 24 hours to perform mechanical grinding and mixing. At this time, the sintering aid is further added to improve final sintering characteristics of the composite mixed conductive layer and to increase densification and sintering density.

Sintering aids include titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ) at least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Add. Sintering aid is added at a ratio of 0 to 30% by weight based on the total weight of the slurry or paste.

The slurry paste thus prepared is screen printed or slurry coated on the surface of the pre-sintered anode support, that is, the functional layer to form a composite mixed conductive layer. The thickness of the composite mixed conductive layer is adjusted by adjusting the number of screen printing or the number of slurry coatings.

In particular, prior to screen printing or slurry coating of the composite mixed conductive layer, the green sheet of the functional layer of the anode and cathode components and, in some cases, the gradient layer of the functional layer for adjusting the shrinkage rate or the composition slightly changes, Screen printing or slurry coating produces a composite mixed conductive layer including a multi-layered functional layer.

The composite mixed conductive layer is formed twice by an average of about 5 to 20 μm in thickness per screen printing or slurry coating.

Thereafter, the support on which the composite mixed conductive layer is formed is subjected to an aging treatment. The aging treatment is to homogenize by holding in an oven at about 70 ℃ for about 1 hour.

 After the aging treatment, the support on which the composite mixed conductive layer was formed was co-sintered at 1400 to 1650 ° C. to prepare a support having a dense composite mixed conductive layer. The thickness of the prepared composite mixed conductive layer is in the range of 5 ~ 40㎛. The support having the composite mixed conductive layer thus prepared is used as a connecting material (separation plate) of the fuel cell.

The paste for screen printing may include a solvent, a dispersant, a conductive composite powder, an organic binder, and a plasticizer.

The solvent is used by mixing isopropyl alcohol and toluene in a ratio of 1: 0 to 5.

In order to prepare a paste for screen printing, first, a solvent in which a dispersant is dissolved in a ball mill container is put in a first milling by mixing a conductive composite powder of an anode or a cathode. The conductive composite powder is mixed to have a specific surface area of 2 ~ 200㎥ / g for uniform mixing. Next, an organic binder and a plasticizer are further added to the first milled mixture to prepare a second mill.

The screen printing paste thus prepared has a viscosity of 10 ² to 10 ⁵ cps and then screen printing.

Screen printing uses a 200mesh stainless steel mesh. Except for the desired pattern, the paste is coated only with a shape by patterning it by covering it with the desired thickness with epoxy resin. 5 to 500 g of solvent (mixing isopropyl alcohol and toluene in a ratio of 1: 0 to 5), 0.1 to 10 g of fish oil, 1 to 10 g of organic binder (PVB), per 100 g of the conductive composite powder when screening paste is prepared. 1-10 g of plasticizer (DBP) was added.

In this case, the composite mixed conductive layer for preparing the anode support type connection material is mixed with YSZ having a particle size of 0.01 ~ 10㎛ and LCCC powder having a particle size of 0.01 ~ 10㎛ in a weight ratio of 5: 5, and the organic binder Most preferably, the plasticizer is further mixed and manufactured by screen printing to a thickness of 5 to 600 µm. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

The support on which the composite mixture conductive layer was formed by co-sintering was mixed with YSZ having a particle size of 0.01-10 μm and LCCC powder having a particle size of 0.01-10 μm at a weight ratio of 2: 5 on the surface of the composite mixed conductive layer. In addition, the catalyst layer may be further formed by screen printing a slurry or paste in which an organic binder and a plasticizer are further mixed to a thickness of 5 to 600 μm. After the formation of the catalyst layer on the surface of the composite mixed conductive layer may be heat treated at a temperature of 600 ℃ or more to complete the final support type connecting member (separation plate).

In the prepared support type connector (separator), the support serves as an anode inductor, the functional layer serves as an anode for electrode reaction, and the composite mixed conductive layer serves as an electrolyte membrane as a dense membrane having electron conductivity and ion conductivity. .

< Example  3>

Preparation of Oxygen Permeation Membrane; Tape Casting Method

Oxygen permeation membrane is pre-sintering the support of the zirconia alumina component, and after forming a composite mixed conductive layer on one or both sides of the support to co-sinter to prepare a support type oxygen permeation membrane.

In addition, the oxygen permeation membrane pre-sinters the support of zirconia or alumina components, forms a functional layer serving as an anode or a cathode on one or both sides of the support, and then uses a green mixed composite conductive layer on the functional layer. It is produced by the tape casting method.

First, at least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), chromium oxide (Cr ₂ O ₃ ) and additives to prepare a support Zirconia doped with low rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide as additive, lanthanumium gallium magnesia oxide At least one powder, an organic binder, a solvent, and a pore-forming agent are mixed, molded into a flat plate, a tube type, or a mixed type, and then heat-treated at a high temperature of 1200 to 1450 ° C. to prepare a sintered porous support.

In some cases, the functional layer to perform the anode or the cathode on one or both surfaces of the pre-sintered porous support and heat treatment at 900 ~ 1600 ℃ can be pre-sintered.

The functional layer is mixed with YSZ having a particle size of 0.01 ~ 10㎛ and LCCC powder having a particle size of 0.01 ~ 10㎛ in a weight ratio of 5: 5, and further mixed with an organic binder and a plasticizer to a thickness of 10 ~ 600㎛ After screen printing on one or both sides of the support may be formed by sintering at a high temperature of 600 ℃ or more. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

The composite mixed conductive layer was mixed with LCCC and YSZ in a weight ratio of 5: 5, and further ball milled for 24 hours with ethyl alcohol to perform mechanical grinding and mixing. At this time, the sintering aid is further added to improve final sintering characteristics of the composite mixed conductive layer and to increase densification and sintering density.

Sintering aids include titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ) at least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Add. Sintering aid is added at a ratio of 0 to 30% by weight based on the total weight of the slurry or paste.

Slurry mixed with LCCC, 8YSZ, ethyl alcohol, and sintering aid is produced into a green sheet having a thickness of about 60 μm on a release film through tape casting. At this time, the release film used uses a mylar film of about 80㎛ thickness.

The green sheet to which the mylar film is attached is attached on top of the functional layer of the support, and the mylar film is removed from the green sheet.

Mylar film is attached to the support and the green sheet by using a pressure-sensitive or pressure-sensitive attachment device, and then remove the mylar film from the green sheet.

Alternatively, the solvent or oil is applied to the support or the green sheet to directly attach the support and the green sheet, and then remove the mylar film from the green sheet. The solvent or oil uniformly attaches the support and the green sheet and facilitates the removal of the mylar film. Terpineol is used as a solvent.

After removing the mylar film as described above in order to control the thickness of the composite mixed conductive layer, the green sheet produced through the tape casting is repeatedly attached to the upper part of the first attached green sheet and the mylar film from the green sheet. Remove it.

Alternatively, prior to attaching the green sheet of the composite mixed conductive layer, the green sheet of the functional layer of the anode and the cathode components and in some cases, the green sheet of the functional layer for adjusting the shrinkage rate or the gradient functional layer slightly changing the composition is applied as described above. The composite mixed conductive layer including the functional layer of the multi-layer structure is manufactured by the process of.

In this example, the green sheet was attached twice.

Thereafter, the support on which the green sheet is attached is aged. The aging treatment is to homogenize by holding in an oven at about 70 ℃ for about 1 hour.

After the aging treatment, the support with the green sheet is co-sintered at 1400 to 1650 ° C. to prepare a support having a dense composite mixed conductive layer. The thickness of the prepared composite mixed conductive layer is in the range of 10 ~ 30㎛. The composite mixed conductive layer thus prepared is used as the oxygen permeation membrane of the electrolytic cell.

In addition, the slurry for the green sheet for tape casting preferably includes a solvent, a dispersant, a conductive composite powder, an organic binder, and a plasticizer.

The solvent is used by mixing ethyl alcohol and toluene in a ratio of 1: 0-5.

In order to prepare a slurry for a green sheet for tape casting, first, a solvent in which a dispersant is dissolved in a ball mill container is added, and then the conductive composite powder is mixed to perform first milling. The conductive composite powder of the anode or cathode is mixed with a specific surface area of 2 ~ 200 ㎥ / g for uniform mixing. Next, an organic binder and a plasticizer are further added to the first milled mixture to prepare a second mill.

The prepared green sheet slurry is subjected to a tape casting process after the viscosity is between 10 ³ and 10 ⁵ cps. Green sheet is manufactured by performing a tape casting of the desired thickness in the range of 20 ~ 2000㎛ the height of the blade at a feed rate of 1 to 50cm / min using a silicon-coated mylar film on one side.

The green sheet slurry for tape casting is 5 to 200 g of solvent (mixing ethyl alcohol and toluene in a ratio of 1: 0 to 5) per 100 g of the conductive composite powder, 0.1 to 10 g of a dispersant (fish oil), and 1 to 1 organic binder (PVB). 10 g and 1 to 10 g of plasticizer (DBP) were added.

The support on which the composite mixture conductive layer was formed by co-sintering was mixed with YSZ having a particle size of 0.01-10 μm and LCCC powder having a particle size of 0.01-10 μm at a weight ratio of 2: 5 on the surface of the composite mixed conductive layer. In addition, the catalyst layer may be further formed by screen printing or slurry coating a slurry or paste in which an organic binder and a plasticizer are further mixed to a thickness of 5 to 600 μm. After the catalyst layer is formed on the surface of the composite mixed conductive layer, heat treatment is performed at a temperature of 600 ° C. or higher to complete an electrolytic cell having a final oxygen permeation membrane.

< Example  4>

Preparation of oxygen permeation membrane; screen printing

Oxygen permeation membrane is pre-sintering the support of the zirconia alumina component, and after forming a composite mixed conductive layer on one or both sides of the support to co-sinter to prepare a support type oxygen permeation membrane.

In addition, the oxygen permeation membrane pre-sinters the support of zirconia or alumina components, forms a functional layer serving as an anode or a cathode on one or both sides of the support, and then uses a green mixed composite conductive layer on the functional layer. It is produced by the tape casting method.

First, at least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), chromium oxide (Cr ₂ O ₃ ) and additives to prepare a support Zirconia doped with low rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide as additive, lanthanumium gallium magnesia oxide At least one powder, an organic binder, a solvent, and a pore-forming agent are mixed, molded into a flat plate, a tube type, or a mixed type, and then heat-treated at a high temperature of 1200 to 1450 ° C. to prepare a sintered porous support.

In the case of graphite added for pore formation, the particle size and mixing ratio are appropriately adjusted.

Next, a functional layer may be formed on one side or both sides of the support.

The functional layer is mixed with YSZ having a particle size of 0.01 ~ 10㎛ and LCCC powder having a particle size of 0.01 ~ 10㎛ in a weight ratio of 5: 5, and further mixed with an organic binder and a plasticizer to a thickness of 5 ~ 600㎛ After screen printing on one or both sides of the support may be formed by sintering at a high temperature of 600 ℃ or more. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

Next, a composite mixed conductive layer is formed on the functional layer. When the functional layer is not formed on one or both sides of the support, a composite mixed conductive layer is formed on one or both sides of the support.

The composite mixed conductive layer is composed of LCCC having (La _x Ca _{1 -x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1) and YSZ doped with yttrium (Y). Was mixed at a weight ratio of 5: 5, and a solvent and a provider such as isopropyl alcohol were further mixed and ball milled for 24 hours to perform mechanical grinding and mixing. At this time, the sintering aid is further added to improve final sintering characteristics of the composite mixed conductive layer and to increase densification and sintering density.

Sintering aids include titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ) at least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Add. Sintering aid is added at a ratio of 0 to 30% by weight based on the total weight of the slurry or paste.

The slurry paste thus prepared is screen printed or slurry coated on the surface of the pre-sintered anode support, that is, the functional layer to form a composite mixed conductive layer. The thickness of the composite mixed conductive layer is adjusted by adjusting the number of screen printing or the number of slurry coatings.

In particular, prior to screen printing or slurry coating of the composite mixed conductive layer, the green sheet of the functional layer of the anode and cathode components and, in some cases, the gradient layer of the functional layer for adjusting the shrinkage rate or the composition slightly changes, Screen printing or slurry coating produces a composite mixed conductive layer including a multi-layered functional layer.

The composite mixed conductive layer is formed twice by an average of about 5 to 20 μm in thickness per screen printing or slurry coating.

Thereafter, the support on which the composite mixed conductive layer is formed is subjected to an aging treatment. The aging treatment is to homogenize by holding in an oven at about 70 ℃ for about 1 hour.

 After the aging treatment, the support on which the composite mixed conductive layer was formed was co-sintered at 1400 to 1650 ° C. to prepare a support having a dense composite mixed conductive layer. The thickness of the prepared composite mixed conductive layer is in the range of 5 ~ 40㎛.

The paste for screen printing may include a solvent, a dispersant, a conductive composite powder, an organic binder, and a plasticizer.

The solvent is used by mixing isopropyl alcohol and toluene in a ratio of 1: 0 to 5.

In order to prepare a paste for screen printing, first, a solvent in which a dispersant is dissolved in a ball mill container is put in a first milling by mixing a conductive composite powder of an anode or a cathode. The conductive composite powder is mixed to have a specific surface area of 2 ~ 200㎥ / g for uniform mixing. Next, an organic binder and a plasticizer are further added to the first milled mixture to prepare a second mill.

The screen printing paste thus prepared has a viscosity of 10 ² to 10 ⁵ cps and then screen printing.

Screen printing uses a 200mesh stainless steel mesh. Except for the desired pattern, the paste is coated only with a shape by patterning it by covering it with the desired thickness with epoxy resin. 5 to 500 g of solvent (mixing isopropyl alcohol and toluene in a ratio of 1: 0 to 5), 0.1 to 10 g of fish oil, 1 to 10 g of organic binder (PVB), per 100 g of the conductive composite powder when screening paste is prepared. 1-10 g of plasticizer (DBP) was added.

In this case, the composite mixed conductive layer for preparing the anode support type connection material is mixed with YSZ having a particle size of 0.01 ~ 10㎛ and LCCC powder having a particle size of 0.01 ~ 10㎛ in a weight ratio of 5: 5, and the organic binder Most preferably, the plasticizer is further mixed and manufactured by screen printing to a thickness of 5 to 600 µm. LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), YSZ is a zirconium oxide doped with yttrium (Y) 8 mol% ( ZrO ₂ ).

The support on which the composite mixture conductive layer was formed by co-sintering was mixed with YSZ having a particle size of 0.01-10 μm and LCCC powder having a particle size of 0.01-10 μm at a weight ratio of 2: 5 on the surface of the composite mixed conductive layer. In addition, the catalyst layer may be further formed by screen printing a slurry or paste in which an organic binder and a plasticizer are further mixed to a thickness of 5 to 600 μm. After the formation of the catalyst layer on the surface of the composite mixed conductive layer may be heat treated at a temperature of 600 ℃ or more to complete the final oxygen permeation membrane.

In the prepared support-type oxygen permeation membrane, the support serves as a fuel electrode insulator, the functional layer serves as a fuel electrode for electrode reaction, and the composite mixed conductive layer serves as an oxygen permeation membrane as a dense membrane having electron conductivity and ion conductivity.

The support on which the composite mixture conductive layer was formed by co-sintering was mixed with YSZ having a particle size of 0.01-10 μm and LCCC powder having a particle size of 0.01-10 μm at a weight ratio of 2: 5 on the surface of the composite mixed conductive layer. In addition, the catalyst layer may be further formed by screen printing or slurry coating a slurry or paste in which an organic binder and a plasticizer are further mixed to a thickness of 5 to 600 μm. After the catalyst layer is formed on the surface of the composite mixed conductive layer, heat treatment is performed at a temperature of 600 ° C. or higher to complete an electrolytic cell having a final oxygen permeation membrane.

Hereinafter, the present invention will be described through experimental examples. Experimental examples and the like described below are intended to support the effects of the present invention, the present invention is not limited thereto and can be variously modified and changed.

< Experimental Example  1>

The sintered density, microstructure, and electrical resistance were measured according to the weight ratio of the conductive composite powder forming the composite mixed conductive layer.

The powder for the support was molded and heat-treated to prepare a pre-sintered support. A functional layer was formed on one surface of the support to be plasticized, and then LCCC and YSZ components were formed in the upper portion of the functional layer in a weight ratio of 100: 0 to 0: 100. A slurry prepared by mixing a binder, a solvent, and the like with the mixed conductive composite powder was attached using a tape casting method, a release film was removed, followed by aging and co-sintering to form a composite mixed conductive layer.

Figure 2 shows the sintered density, microstructure, electrical resistance value according to the weight ratio of the conductive composite powder. Here, the electrical conductivity is summarized by the inverse electric resistance [cm 2].

According to FIG. 2, in the case of Experiments 1 to 3 in which the LCCC and YSZ components were less than 90:10, the sintered density was lower than 80%, and a dense composite mixed conductive layer was not formed.

In Experiments 8 and 9, where LCCC and YSZ components exceeded 20:80, a dense complex mixed conductive layer was formed, but the electrical resistance values were as high as 0.12 kcm 2 and 0.15 kcm 2. If the electrical resistance value is higher than 0.035Ωcm 2, the electron conductivity is lost and it cannot be used as an oxygen permeation membrane or a hydrogen permeation membrane.

In FIG. 2, the microstructured region in the ellipse corresponds to the oxygen permeation membrane.

In FIG. 2, the fine structure of the microstructure shows a dense oxygen permeation membrane (LCD: YSZ) at 90:10 or more, resulting in a dense oxygen permeation membrane. However, when the LCCC: YSZ exceeds 20:80, The resistance value increased.

Although not shown in FIG. 2, LCCC: YSZ showed an electrical resistance value of 0.05 m 2 at a weight ratio of 10:90, and did not exceed 0.10 m 2. When the electrical resistance is 0.05 m 2, the electron conductivity is bad, but the electron conductivity is not lost. Therefore, it is included in the scope of the present invention.

And LCCC: YSZ suddenly increased to 0.12 m <2> by 7:93 weight ratio, and exceeded 0.10 m <2>.

The sudden increase in the electrical resistance value means that the electron permeability is lost and oxygen permeability is rapidly deteriorated. If the electrical resistance value is 0.10 m 2 or more, the oxygen permeability deteriorates rapidly. Therefore, when LCCC: YSZ exceeds 10:90, it can be seen that it cannot be used as an oxygen permeation membrane.

From the experimental results, it can be seen that the LCCC and YSZ components forming the composite mixed conductive layer are most effective as the oxygen permeation membrane when mixed in a weight ratio of 90:10 to 20:80. In addition, it can be seen that the LCCC and YSZ components forming the composite mixed conductive layer are also effective as oxygen permeation membranes when mixed in a weight ratio of 90:10 to 10:90.

Here, LCCC is a material dedicated to electron conduction only, and YSZ is a material dedicated to conduction of oxygen ions, and the electron and oxygen conductivity, which are the core reactions required for oxygen permeation separation, are added to each other by adding each of them in a different phase. To get up.

This improves the reactivity, greatly increases the permeation of oxygen ions, promotes sintering, and provides a composite mixed conductive layer as an oxygen permeable membrane that is a dense membrane.

LCCC and YSZ are mixed to obtain a composite mixed conductive layer that is a dense film. The reaction of YSZ and LCCC produces a small amount of liquid components at the sintering temperature, which promotes sintering, and volatilization of the La component at high temperature. It is because it suppresses and promotes sintering and densification.

In addition, the trace amount of the liquid component produced by the reaction of YSZ and LCCC is a liquid component that appears only temporarily during sintering, and when cooled after sintering, it again does not penetrate the solid phase YSZ and LCCC. In this case, the microstructure of the manufactured composite mixed conductive layer is not found and there is no change in the electrical resistance, thereby reducing the resistance of the composite mixed conductive layer.

In addition, even though the LCCC film was thinner and densified, the path (pores) where the reaction gas of hydrogen or air directly leaked disappeared, and the electrical resistance was kept small enough, and the electrical resistance value was 0.035 m 2 or less even after 48 hours of operation. The value is shown.

As such, the present invention includes a conductive composite (dual-phase) powder in preparing the LCCC-based oxygen permeation membrane, which is very advantageous for densification during sintering and at a low cost from limiting the amount of YSZ added to the LCCC to 10 to 90%. It can be seen that an effective oxygen permeation membrane can be prepared.

< Experimental Example  2>

When the oxygen permeation membrane is prepared using only LCCC without YSZ and (La _x Ca _{1 -x} ) (Co _y Cr _{1 -y} ) O ₃ (0≤x≤1, 0≤y≤1), a dense membrane is obtained. Make it difficult to lose.

La-based perovskite compounds, such as (La _x Ca _{1- x} ) (Co _y Cr _{1- y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1), are sinterable materials. Lanthanum (La) oxide is slightly volatile at the sintering temperature of 1200 ~ 1450 ℃. If there is volatility, the perovskite composition (ABO ₃ ) cannot maintain the chemical formula, so that the densification process does not proceed during sintering and the porosity is maintained to a certain level.

According to FIG. 3, the microstructure of the porous LCCC layer (monocomponent system) formed in the support body is confirmed.

When the porous LCCC layer shown in FIG. 3 is used as an oxygen permeation membrane, hydrogen gas leaks during operation and reacts rapidly with oxygen on the opposite side to oxidize Ni, which is a surrounding metal, to make NiO to accelerate deterioration and corrosion due to volume expansion. Let's do it. When the corrosion accelerates, the voltage change is not stable and the resistance is rapidly increased, and the resistance sharply rises, and the role of the connecting material (separator plate) or the characteristics of the oxygen permeable membrane rapidly deteriorate.

The electrical resistance value rapidly increased from 0.04 m 2 to 0.3 m 2 after several hours of operation.

According to FIG. 4, a microstructure in which severe corrosion occurred in the porous LCCC layer after 24 hours of operation was confirmed.

Thus for densification CrO ₂ Sintering aids, such as these, are added. The sintering aid may promote the sintering to form a dense film by forming a small amount of liquid phase during sintering, but due to the excessive addition, the liquid phase remains between the LCCC particles and the LCCC particles after sintering, and the electrical conductivity of the dense film is poor at room temperature. do.

< Experimental Example  3>

A composite mixed conductive layer including LCCC and YSZ components was formed on a support prepared according to the present invention, and the microstructure is shown in FIG. 5 after 24 hours of operation.

 According to Figure 5, a dense film was made and no corrosion occurred even after 24 hours of operation.

In addition, as shown in FIGS. 6 and 7, the voltage was stable even in the long-term operation test of the voltage curve, and the electric resistance value was also kept small enough to show a value of 0.32 mm 2 or less even after 48 hours of operation.

From these results, the present invention can form a composite mixed conductive layer having a dense membrane and excellent electrical conductivity on a support, and using the composite mixed conductive layer as an oxygen permeable separator and a connecting material (separator) for electrolytic cells, fuel cells, and the like. It can be seen that the performance can be improved.

The scope of the present invention is not limited to the embodiments described above, but may be defined by the scope of the claims, and those skilled in the art may make various modifications and alterations within the scope of the claims It is self-evident.

10: support 20: composite mixed conductive layer
30: Functional layer (fuel electrode, air electrode, inclination) 40: Catalyst layer

Claims (40)

Forming a support;
Coating a slurry or paste comprising a conductive composite powder which is a mixture composed of at least two phases on one or both surfaces of the support to form a dense film on one or both surfaces of the support. forming a mixed conductor;
Method of manufacturing a support with a composite mixed conductive layer characterized in that it comprises the step of co-sintering the support on which the composite mixed conductive layer is formed. The method according to claim 1,
Wherein forming the support comprises:
A method for producing a composite mixed conductive layer-coated support, characterized in that to form a sintered support by molding a powder for a support including a binder, a pore-forming agent and heat treatment. The method according to claim 1,
Wherein forming the support comprises:
After mixing a binder and a pore-forming agent with a support powder containing at least one of nickel metal and nickel oxide and the YSZ component, and molding
A method for producing a composite mixed conductive layer coated support, characterized in that to form a sintered porous support by heat treatment at 600 ~ 1600 ℃.
(Here, YSZ is yttria stabilized zirconia, and zirconium oxide (ZrO ₂ ) is doped with yttrium (Y) in the range of 2 mol% to 20 mol%.) The method of claim 3,
At least one of the nickel metal and nickel oxide (NiO) and the YSZ component is a method for producing a composite mixed conductive layer coated support, characterized in that the mixture at a weight ratio of 3: 7 to 7: 3.
(Here, YSZ is yttria stabilized zirconia, and zirconium oxide (ZrO ₂ ) is doped with yttrium (Y) in the range of 2 mol% to 20 mol%.) The method according to claim 1,
Wherein forming the support comprises:
At least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), and chromium oxide (Cr ₂ O ₃ ),
One or more powders of zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxides, and lanthanum strontium gallium magnesia oxide After mixing with the binder, the pore-forming agent and molding
A method for producing a composite mixed conductive layer coated support, characterized in that to form a sintered porous support by heat treatment at 600 ~ 1600 ℃. The method according to claim 1,
Wherein forming the support comprises:
As the ABO ₃ perovskite structural compound, at least one of lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y) occupies the A site. B is one of manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu) and bismuth (Bi) The conductive ceramic powder which an ideal occupies,
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide The powder, the binder and the pore-forming agent are mixed and then molded
A method for producing a composite mixed conductive layer coated support, characterized in that to form a sintered porous support by heat treatment at 600 ~ 1600 ℃. The method according to claim 1,
Wherein forming the support comprises:
A ₂ BO ₄ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y), praseodymium (Pr) , Neodymium (Nd) is occupied by one or more species, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), Conductive ceramic powders occupied by at least one of copper (Cu) and bismuth (Bi);
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide The powder, the binder and the pore-forming agent are mixed and then molded
A method for producing a composite mixed conductive layer coated support, characterized in that to form a sintered porous support by heat treatment at 600 ~ 1600 ℃. The method according to claim 1,
Wherein forming the support comprises:
At least one of zirconia-based oxides, alumina oxides, mullite oxides, silicate oxides, carbides, and nitrides is mixed with an organic binder, a solvent, and a pore-forming agent, and then molded.
A method for producing a composite mixed conductive layer coated support, characterized in that to form a sintered porous support by heat treatment at 600 ~ 1600 ℃. The method according to claim 1,
The support is a plate-type, tubular or mixed composite conductive conductive layer, characterized in that the manufacturing method of the support coated. The method according to claim 1,
Forming the composite mixed conductive layer,
Slurry or paste containing a conductive composite powder, a solvent, a binder on one or both sides of the support
A method of manufacturing a support with a composite mixed conductive layer, characterized in that the coating is formed by any one of slurry coating, dipping, spray coating, spin coating, screen printing, tape casting and heat treatment. The method according to claim 1 or 10,
The conductive composite powder
As the ABO ₃ perovskite structural compound, at least one of lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y) occupies the A site. B is one of manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu) and bismuth (Bi) The conductive ceramic powder which an ideal occupies,
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide Method for producing a support with a composite mixed conductive layer characterized in that the powder is mixed. The method of claim 11,
The conductive ceramic powder and the electrolyte powder is a method for producing a composite mixed conductive layer coated support, characterized in that mixed in a weight ratio of 90:10 ~ 10:90. The method according to claim 1 or 10,
The conductive composite powder
A ₂ BO ₄ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y), praseodymium (Pr) , Neodymium (Nd) is occupied by one or more species, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), Conductive ceramic powders occupied by at least one of copper (Cu) and bismuth (Bi);
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide Method for producing a support with a composite mixed conductive layer characterized in that the powder is mixed. 14. The method of claim 13,
The conductive ceramic powder and the electrolyte powder is a method for producing a composite mixed conductive layer coated support, characterized in that mixed in a weight ratio of 90:10 ~ 10:90. The method according to claim 1 or 10,
The conductive composite powder
LCCC and YSZ component is a method for producing a composite mixed conductive layer coated support characterized in that it is included in a weight ratio of 90:10 ~ 20:80.
Where LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),
YSZ is yttria stabilized zirconia, in which zirconium oxide (ZrO ₂ ) is doped with yttrium (Y) in the range of 2 mol% to 20 mol%) The method according to claim 1 or 10,
Said slurry or paste further comprises a sintering aid. 18. The method of claim 16,
The sintering aid
Titanium dioxide (TiO ₂ ), manganese dioxide (MnO ₂ ), strontium carbonate (SrCO ₃ ), barium carbonate (BaCO ₃ ), calcium carbonate (CaCO ₃ ), silicon dioxide (SiO ₂ ), chromium oxide (Cr ₂ O ₃ ), At least one of bismuth oxide (Bi ₂ O ₃ ), yttrium oxide (Y ₂ O ₃ ), ceria (CeO ₂ ), scandium oxide (Sc ₂ O ₃ ), and neodium oxide (Nb ₂ O ₃ ) Method for producing a support with a composite mixed conductive layer to be coated. The method according to claim 1,
The composite mixed conductive layer is a method for producing a composite mixed conductive layer coated support, characterized in that to control the thickness by repeatedly coating a slurry or paste containing a conductive composite powder on one or both surfaces of the support. . The method according to claim 1 or 18,
The thickness of the composite mixed conductive layer is 0.1 ~ 900㎛ method for producing a support coated with a composite mixed conductive layer, characterized in that. The method according to claim 1 or 18,
The sintered density of the composite mixed conductive layer is 70% or more 100% or less method for producing a composite mixed conductive layer coated support characterized in that. The method according to claim 1,
Before the step of forming a composite mixed conductive layer on one or both sides of the support,
Forming a functional layer constituting the anode or the cathode on one or both sides of the support is a method for producing a composite mixed conductive layer coated support characterized in that the step is performed in advance. The method according to claim 1,
Before the step of forming a composite mixed conductive layer on one or both sides of the support,
Support for coating a composite mixed conductive layer, characterized in that the step of forming a functional layer for solving the difference in thermal expansion rate difference or sinter shrinkage shrinkage between the support and the composite mixed conductive layer on one side or both sides of the support Manufacturing method. The method according to claim 1,
Before the step of forming a composite mixed conductive layer on one or both sides of the support,
Forming a gradient functional layer or a gradient functional layer of a multi-layer structure on one or both surfaces of the support by changing the composition between the support and the composite mixed conductive layer little by little, the composite mixed conductive layer is coated Of the prepared support. The method according to claim 1,
After co-sintering the support on which the composite mixed conductive layer is formed,
And forming a catalyst layer constituting a fuel electrode or an air electrode on top of the composite mixed conductive layer. A support comprising a support powder component;
Composite layers of mixed conductor formed on one or both sides of the support, and are dense membranes containing conductive composite powder components, which are mixtures of two or more phases having electronic conductivity and ion conductivity. A composite mixed conductive layer coated support, characterized in that it comprises a). 26. The method of claim 25,
The support powder
A support having a composite mixed conductive layer coated with at least one of nickel metal and nickel oxide and an YSZ component. 26. The method of claim 25,
The support powder
At least one powder of nickel oxide (NiO), cobalt oxide (CoO), copper oxide (CuO), iron trioxide (Fe ₂ O ₃ ), and chromium oxide (Cr ₂ O ₃ ),
One or more powders of zirconia doped with rare earth or alkali (earth) metal oxides, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxides, and lanthanum strontium gallium magnesia oxide A composite mixed conductive layer coated support comprising a. 26. The method of claim 25,
The support powder
A support coated with a composite mixed conductive layer, characterized in that at least one of zirconia-based oxide, alumina oxide, mullite oxide, silica oxide, carbide and nitride. 26. The method of claim 25,
The support powder or the conductive composite powder
As the ABO ₃ perovskite structural compound, at least one of lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), and yttrium (Y) occupies the A site. B is one of manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), copper (Cu) and bismuth (Bi) The conductive ceramic powder which an ideal occupies,
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, or lanthanum strontium gallium magnesia oxide A composite mixed conductive layer coated support, characterized in that it comprises a powder. 26. The method of claim 25,
The support powder or the conductive composite powder
A ₂ BO ₄ perovskite structural compound, in place of A, lanthanum (La), strontium (Sr), calcium (Ca), barium (Ba), samarium (Sm), yttrium (Y), praseodymium (Pr) , Neodymium (Nd) is occupied by one or more species, and in the B position manganese (Mn), cobalt (Co), iron (Fe), chromium (Cr), yttrium (Y), titanium (Ti), nickel (Ni), Conductive ceramic powders occupied by at least one of copper (Cu) and bismuth (Bi);
At least one electrolyte of zirconia doped with rare earth or alkali (earth) metal oxide, ceria, bismuth oxide, barium strontium cerate compound doped with rare earth or alkali (earth) metal oxide, and lanthanum strontium gallium magnesia oxide A composite mixed conductive layer coated support, characterized in that it comprises a powder. 26. The method of claim 25,
The conductive composite powder
A composite mixed conductive layer coated support, characterized in that the conductive ceramic powder and the electrolyte powder are included in a weight ratio of 90:10 to 10:90. 26. The method of claim 25,
The conductive composite powder
LCCC and YSZ component is a composite mixed conductive layer characterized in that it is included in a weight ratio of 90:10 ~ 10:90.
Where LCCC is (La _x Ca _{1- x} ) (Co _y Cr _{1 -y} ) O ₃ (0 ≦ x ≦ 1, 0 ≦ y ≦ 1),
YSZ is yttria stabilized zirconia and is doped with zirconium oxide (ZrO ₂ ) in the range of 2 mol% to 20 mol% of yttrium (Y). 26. The method of claim 25,
The composite mixed conductive layer has a composite mixed conductive layer coated support, characterized in that the sintered density is 70% or more and 100% or less. 26. The method of claim 25,
The composite mixed conductive layer is a support having a composite mixed conductive layer characterized in that the thickness is 0.1 ~ 900㎛. 26. The method of claim 25,
The support is coated with a composite mixed conductive layer, characterized in that the flat plate, tubular or a mixture thereof. 26. The method of claim 25,
The support or the support on which the composite mixed conductive layer is formed
A support having a composite mixed conductive layer, characterized in that used in any one or more of a fuel cell, an electrolysis cell, an electrochemical device as a fuel electrode, an air electrode, a separator (Separator), a membrane (Membrane). The method of claim 25 or 35,
A support substrate having a composite mixed conductive layer, characterized in that a functional layer constituting a fuel electrode or an air electrode is formed between the support and the composite mixed conductive layer. The method of claim 25 or 35,
A support layer coated with a composite mixed conductive layer, characterized in that a functional layer is formed between the support and the composite mixed conductive layer to solve a difference in thermal expansion rate or sinter shrinkage between the support and the composite mixed conductive layer. The method of claim 25 or 35,
And a gradient functional layer or a gradient functional layer having a multilayer structure formed by changing a composition between the support and the composite mixed conductive layer little by little between the support and the composite mixed conductive layer. The method of claim 25 or 35,
And a catalyst layer constituting a fuel electrode or an air electrode formed on the composite mixed conductive layer.

Images