JP2002343367A - Fuel cell and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid polymer fuel cell, liquid fuel cell and an electrode with high safety in a product and production process, little spread unevenness or application defect, of low cost and high discharge performance by optimizing surface active agent in order to improve molecular mass electrolyte in a catalyst layer of a fuel cell, dispersibility of carbon powder and a binder. SOLUTION: By utilizing a catalyst layer made from a mixture containing carbon, optimized surface active agent and polymer electrolyte, a solid polymer electrolyte fuel cell, a liquid fuel cell and an electrode exerting a high performance are provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a fuel using hydrogen gas, reformed hydrogen from methanol or fossil fuel, or liquid fuel such as methanol, ethanol or dimethyl ether directly as fuel, and using air or oxygen as an oxidant. The present invention relates to a battery, and particularly to a fuel cell using a polymer electrolyte, and more particularly to an electrode thereof and a method of manufacturing the same.

[0002]

2. Description of the Related Art First, a general configuration of a conventional solid polymer electrolyte fuel cell will be described. A fuel cell using a polymer electrolyte generates electricity and heat simultaneously by electrochemically reacting a fuel gas containing hydrogen and an oxidizing gas containing oxygen such as air.

FIG. 1 is a schematic sectional view for explaining a partial structure of a unit cell of a solid polymer electrolyte fuel cell.
As shown in FIG. 1, on both surfaces of a polymer electrolyte membrane 11 for selectively transporting hydrogen ions, a carbon powder carrying a platinum-based metal catalyst is used as a catalyst, and a hydrogen ion-conductive polymer electrolyte is mixed therewith. Thus, the catalyst layer 12 is formed.

At present, the polymer electrolyte membrane 11 has the following formula:

[0005]

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[0006] A polymer electrolyte membrane made of perfluorocarbon sulfonic acid represented by, for example, US
A Nafion membrane manufactured by T Co., Ltd.) is generally used. On the outer surface of the catalyst layer 12, a gas diffusion layer 13 is formed of, for example, carbon paper having both air permeability and electron conductivity and subjected to a water-repellent treatment. The catalyst layer 12 and the gas diffusion layer 13 are collectively called an electrode 14.

Next, in order to prevent the supplied fuel gas and the oxidizing gas from leaking outside and to prevent the two types of gases from being mixed with each other, a gas sealing material or a gasket is provided around the electrodes with a polymer electrolyte membrane interposed therebetween. Be placed. The sealing material and the gasket are integrated with the electrode and the polymer electrolyte membrane in advance and assembled, and this is referred to as MEA (electrolyte membrane electrode assembly) 15.

As shown in FIG. 2, a conductive separator plate 21 for mechanically fixing the MEA 15 is disposed outside the MEA 15. FIG. 2 is a schematic cross-sectional view for explaining the structure of a unit cell of the solid polymer electrolyte fuel cell. A gas flow path 22 for supplying a reaction gas to the electrode surface and carrying away generated gas and surplus gas is formed in a portion of the separator plate 21 that contacts the MEA 15. Although the gas flow path can be provided separately from the separator plate, a method of providing a gas flow path by providing a groove on the surface of the separator is general. Thus, the MEA 15 is formed by the pair of separator plates 21.
Is fixed, and the fuel gas is supplied to one gas flow path and the oxidizing gas is supplied to the other gas flow path, so that a single cell can generate an electromotive force of about 0.8 V.

A cell in which the MEA is fixed by a pair of separators is called a unit cell 23. However, normally, when a fuel cell is used as a power source, a voltage of several volts to several hundred volts is required. Therefore, in practice, the required number of cells 23 are connected in series. At this time, the gas flow paths 22 are formed on both sides of the separator 21 and the separator / MEA / separator / MEA is repeated to form a series connection configuration.

In order to supply gas to the gas flow path, a pipe jig for branching a gas supply pipe into a number corresponding to the number of separators to be used and connecting the branch directly to a separator-like groove. Is required. This jig is referred to as a manifold, and in particular, the type directly connected from the fuel gas supply pipe as described above is referred to as an external manifold. There is a type of this manifold called an internal manifold which has a simpler structure. The internal manifold is provided with a through hole in the separator plate on which the gas flow path is formed,
The entrance and exit of the gas flow path are passed to this hole, and the gas is supplied directly to the gas flow path from this hole.

The gas diffusion layer and the catalyst layer constituting the electrodes of the fuel cell as described above will be described.

The gas diffusion layer mainly has the following three functions. The first is the function of diffusing the reaction gas in order to uniformly supply the reaction gas such as a fuel gas or an oxidizing gas to the catalyst in the catalyst layer from the gas passage formed on the outer surface of the gas diffusion layer. It is. The second is a function of quickly discharging water generated by the reaction in the catalyst layer to the gas channel. The third is a function of conducting electrons required for the reaction or generated electrons. That is, the gas diffusion layer requires high reaction gas permeability, water vapor permeability and electron conductivity.

As a conventional general technique, in order to impart gas permeability, a conductive porous substrate such as carbon powder, pore-forming material, carbon paper and carbon cloth having a developed structure is used for a gas diffusion layer. To have a porous structure. Further, in order to impart water vapor permeability, a water-repellent polymer represented by a fluororesin is dispersed in a gas diffusion layer or the like. Further, in order to provide electron conductivity, a gas diffusion layer is made of an electron conductive material such as carbon fiber, metal fiber, and carbon powder.

Next, the catalyst layer mainly has the following four functions. The first function is to supply a reaction gas such as a fuel gas or an oxidizing gas supplied from the gas diffusion layer to a reaction site of the catalyst layer. The second function is to quickly transfer hydrogen ions required for the reaction on the catalyst or generated hydrogen ions to the electrolyte membrane. The third is a function of conducting electrons required for the reaction or generated electrons.
Fourth, high catalytic performance for prompt reaction and a wide reaction area. That is, the catalyst layer needs to have high reaction gas permeability, hydrogen ion permeability, electron conductivity and catalytic performance.

As a conventional general technique, a porous structure is formed by using carbon powder or a pore-forming material having a well-developed structure for the catalyst layer in order to impart gas permeability. Further, in order to provide hydrogen ion permeability, a polymer electrolyte is dispersed in the vicinity of a catalyst in a catalyst layer to form a hydrogen ion network. Further, in order to impart electron conductivity, a catalyst carrier is made of an electron conductive material such as carbon powder or carbon fiber. Furthermore, in order to improve the catalytic performance, a highly reactive metal catalyst represented by platinum is supported on carbon powder as very fine particles having a particle size of several nm, and is highly dispersed in the catalyst layer. Has been done.

[0016]

However, it is very difficult to disperse the polymer electrolyte in the catalyst layer near the catalyst in the catalyst layer to form a good hydrogen ion network.

That is, when the carbon powder generally used for the catalyst layer is a carbon powder having a specific surface area of several tens to several thousand m ² , primary particles of several tens of nm are further bonded to form a chain-like aggregate (structure). Therefore, it is possible to uniformly disperse the ionomer of the polymer electrolyte of several hundred nm represented by the chemical formula 6 in the vicinity of the catalyst surface supported and adsorbed in the pores of several nm to several 100 nm inside the structure. It is difficult to secure a sufficient effective reaction area of the catalyst, and it is also difficult to form a hydrogen ion network by bonding between the polymer electrolyte ionomers, so that sufficient hydrogen ion conductivity cannot be ensured. There was a problem that.

Further, since the carbon powder used for the catalyst layer has a structural structure, a catalyst ink prepared by mixing the catalyst powder with a polymer electrolyte, water, alcohol, or another organic solvent is very difficult. It is easy to agglomerate, and with ordinary stirring and dispersion methods such as stirrer and ultrasonic bath,
The particle size distribution has a median diameter of several tens of μm. Therefore, several μm to several tens μm are used for films, diffusion layers, transfer films, etc.
When a catalyst layer of m is applied, it becomes an agglomerated layer of the catalyst layer powder of several tens of μm, so it is difficult to apply a thin film thinner than several tens of μm, and a dense and smooth coating film cannot be obtained. There was a problem that.

Therefore, conventionally, various surfactants have been used to obtain a good dispersion state. For example, Japanese Patent Application Laid-Open No. 11-335886,
1-269689, 11-050290,
As disclosed in JP-A-10-092439 and JP-A-06-116774, as a surfactant used as a dispersant for a water-repellent polymer material, octylphenol ethoxylate of alkylphenols is used.
thoxylate), the specific product name is Triton X-10
0 is used. In Japanese Patent Application Laid-Open No. 6-036771, fatty acids soaps, alkylbenzenesulfonates, alkylallylsulfonates, alkylnaphthalenesulfonates, as anionic surfactants, are used as general surfactants.
In cationic systems, alkylamine salts, amide-bonded amide salts, ester-bonded amine salts, alkylammonium salts,
Amide bond ammonium salt, ester bond ammonium salt, ether bond ammonium salt, alkylpyridinium salt, ester bond pyridinium salt, amphoteric long-chain alkyl amino acid, nonionic alkyl allyl ether, alkyl ether, alkylamine fatty acid glycerin ester, aniline Although hydrosorbitol fatty acid ester, polyethyleneimine, fatty acid alkylolamide and the like are disclosed, in Examples, Triton X-100, which is octylphenol ethoxylate of the above alkylphenols, is also used. Therefore, the above-mentioned various surfactants are merely introductions of general surfactants, and do not show an effect in a fuel cell.

However, the above-mentioned surfactant has a structure optimized mainly for dispersing the water-repellent polymer material in the diffusion layer, and relates to the dispersion of the polymer electrolyte and the carbon powder in the catalyst layer of the present invention. It is not a disclosure of technology.

Further, Japanese Patent Application Laid-Open No. 8-236123,
Japanese Patent Application Laid-Open Nos. 9-180727 and 10-284086 disclose the use of a surfactant for a catalyst layer, and a method of impregnating a polymer electrolyte after mixing a surfactant to form a catalyst layer in advance. Alternatively, a method of impregnating or coating a polymer electrolyte after impregnating a surfactant formed on a catalyst layer formed in advance is disclosed, which is a method of easily permeating the polymer electrolyte into an electrode. In these methods, when forming an electrode, there is no polymer electrolyte also serving as a binder, and the dispersion state of the carbon powder and the polymer electrolyte cannot be controlled using the effect of the surfactant. Therefore, it is impossible to form a hydrogen ion network by simultaneously preventing aggregation of the carbon powder and dispersing the polymer electrolyte, and a dense and smooth coating film cannot be obtained.

The present invention solves the above-mentioned conventional problems. In order to improve the dispersibility of a molecular weight electrolyte and carbon powder in a catalyst layer of a fuel cell and to improve a binder, a product is optimized by using a surfactant. And the safety of the manufacturing process is high,
It is an object of the present invention to provide a polymer electrolyte fuel cell, a liquid fuel cell, and an electrode that have less variation in the amount of coating and poor coating in a manufacturing process, and have low cost and high discharge performance.

[0023]

To solve the above problems, a fuel cell according to the present invention comprises a hydrogen ion conductive polymer electrolyte membrane, a catalyst layer in contact with the hydrogen ion conductive polymer electrolyte membrane, and A pair of electrodes having a gas diffusion layer in contact with the catalyst layer and a pair of conductive separators having a gas flow path for supplying and discharging a fuel gas to one of the electrodes and supplying and discharging an oxidizing gas to the other of the electrodes. Fuel cell,
At least one of the catalyst layers contains carbon powder, a surfactant, and a polymer electrolyte.

Further, the method of manufacturing a fuel cell according to the present invention is characterized in that at least one of the catalyst layers is made of a mixture containing at least carbon powder, a surfactant and a polymer electrolyte.

At this time, the surfactant is desirably represented by the following formula.

[0026]

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As another method, it is desirable to use a surfactant represented by the following formula.

[0028]

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As another method, it is desirable to use a surfactant represented by the following formula.

[0030]

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[0031]

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Further, as another method, it is desirable to use a surfactant represented by the following formula.

[0033]

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By using a surfactant that satisfies the above molecular formula, the polymer electrolyte, carbon powder, and other binders are sufficiently dispersed, and the polymer electrolyte, carbon powder, and other binders are not unevenly distributed. In addition, a sufficient effective reaction area of the catalyst can be ensured, and a sufficient hydrogen ion conductivity can be ensured because a hydrogen ion network can be formed by bonding between the polymer electrolyte ionomers.

Further, the stability of a mixed solution of a polymer electrolyte, carbon powder, and a binder (hereinafter referred to as a catalyst layer ink) is high, and in a production process such as coating and printing, the catalyst layer ink is used for piping and pumps. It has the effect of reducing clogging and concentration change, reducing coating amount variation and coating failure, and consequently improving the discharge performance of the electrode.

Further, among the surfactants that have hitherto been widely used, many of the substances suspected as endocrine disrupting substances are classified as alkylphenols and have a phenol group in the molecule. In contrast, the present invention has no endocrine disrupting action because it does not contain a phenol group, and can be mixed, kneaded,
In manufacturing processes such as coating and printing, safety is improved in the manufacturing process because environmental hormones are not contained.
Further, in order to ensure safety, no special processing steps or equipment such as waste liquid treatment in solvent extraction processing of a surfactant or a scrubber device in a heat treatment device are required, so that manufacturing costs can be reduced. Furthermore, since there is no possibility that trace amounts of environmental hormones remain in the final product, the safety of the product can be ensured, and the need for special disposal treatment is eliminated.

As described above, according to the configuration of the present invention, a fuel cell having high discharge performance and low cost can be realized.

[0038]

EXAMPLES Example 1 Acetylene black as carbon powder (Denka black manufactured by Denki Kagaku Kogyo KK, particle size 3)
5 nm) with polytetrafluoroethylene (PTFE)
Aqueous dispersion (D made by Daikin Industries, Ltd.)
1) to prepare a water-repellent ink containing 20% by weight of PTFE as a dry weight. This ink is used as carbon paper (TGPH manufactured by Toray Industries, Inc.) as a base material of the gas diffusion layer.
060H), and impregnated with hot air drier.
Heat treatment was performed at 00 ° C. to form a gas diffusion layer.

On the other hand, Ketjen Black (Ketjen Black International K.K.)
etjen Black EC: particle size 30 nm)
66 parts by weight of a catalyst supporting 50% by weight of a t-catalyst were added to 33 parts by weight of a perfluorocarbon sulfonic acid ionomer (5% by weight Nafion dispersion manufactured by Aldrich, USA) as a hydrogen ion conductive material and a binder Weight) and a surfactant represented by the following formula were mixed to form a catalyst layer.

[0040]

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The gas diffusion layer and the catalyst layer obtained as described above were combined with a polymer electrolyte membrane (Nafi of Du Pont, USA).
on112 film), and the ME having the structure shown in FIG.
A-a was prepared.

Example 2 A catalyst layer was formed in the same manner as in Example 1 except that a surfactant represented by the following formula was mixed, and a gas diffusion layer and a catalyst layer were formed using a polymer electrolyte membrane (Du Pont, USA).
MEA-b having the structure shown in FIG.

[0043]

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Example 3 A catalyst layer was formed in the same manner as in Example 1 except that a surfactant represented by the following formula was mixed. A gas diffusion layer and a catalyst layer were formed by using a polymer electrolyte membrane (Du Pont, USA).
MEA-c having the structure shown in FIG.

[0045]

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Example 4 A catalyst layer was formed in the same manner as in Example 1 except that a surfactant represented by the following formula was mixed. A gas diffusion layer and a catalyst layer were formed by using a polymer electrolyte membrane (Du Pont, USA).
MEA-d having the structure shown in FIG.

[0047]

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Example 5 A catalyst layer was formed in the same manner as in Example 1 except that a surfactant represented by the following formula was mixed. A gas diffusion layer and a catalyst layer were formed by using a polymer electrolyte membrane (Du Pont, USA).
MEA-e having the structure shown in FIG.

[0049]

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Comparative Example 1 Repellent containing acetylene black (Denka Black manufactured by Denki Kagaku Kogyo KK) and aqueous PTFE dispersion (D1 manufactured by Daikin Kogyo KK) containing 20% by weight of PTFE as a dry weight. A water-based ink was prepared, applied on carbon paper (TGPH060H manufactured by Toray Industries, Inc.) constituting the gas diffusion layer, and heat-treated at 300 ° C. using a hot air drier to form a gas diffusion layer.

On the other hand, Ketjen Black (Ketjen B manufactured by Ketjen Black International Co., Ltd.)
and a perfluorocarbon sulfonic acid ionomer (US A) serving as a hydrogen ion conductive material and a binder.
5 wt% Nafion dispersion manufactured by ldrich) 33
The catalyst layer was formed by mixing with parts by weight and molding.

The gas diffusion layer and the catalyst layer obtained as described above were combined with a polymer electrolyte membrane (Nafi of Du Pont, USA).
on112 film), and the ME having the structure shown in FIG.
Ax was prepared.

<< Examples 6 to 10 and Comparative Example 2 >> Next, a rubber gasket plate was joined to the outer periphery of the polymer electrolyte membrane of the MEA manufactured as described above, and cooling water, fuel gas and oxidizing agent were joined. A manifold hole for gas distribution was formed.

A conductive separator plate made of a graphite plate impregnated with a phenol resin and having a gas flow path and a cooling water flow path having an outer dimension of 20 cm × 32 cm × 1.3 mm and a depth of 0.5 mm was prepared. . Using two of these separator plates, a unit cell was obtained by laminating a separator plate having an oxidizing gas channel formed on one surface of the MEA and a separator plate having a fuel gas channel formed on the back surface.

Two unit cells were stacked and sandwiched by a separator plate in which a cooling channel groove was formed so that the groove was positioned on the MEA side to obtain a two-cell stacked battery. This pattern was repeated to obtain a 100-cell stacked battery. (Stack) was prepared.
At this time, a current collector plate made of stainless steel, an insulating plate made of an electrically insulating material and an end plate were arranged at both ends of the stack, and were fixed with fastening rods. The fastening pressure at this time was 15 kgf / cm2 per area of the separator.

In the fuel cell manufactured by the above method,
MEA-a, MEA-b, MEA-c, MEA
Those using -d, MEA-e or MEA-x were referred to as Battery A, Battery B, Battery C, Battery D, Battery E, and Battery X.

[Evaluation Test] Pure hydrogen gas was supplied to the fuel electrode of the above battery, and air was supplied to the air electrode.
5 ° C., fuel gas utilization rate (Uf) is 70%, air utilization rate (Uo) is 40%, and gas humidification is performed at 70 ° C.
The discharge test of the battery was performed by passing air through a bubbler at 50 ° C.

Further, a 2 mol / l aqueous methanol solution was supplied at a temperature of 60 ° C. as a typical example of liquid fuel to the fuel electrodes of the cells of the examples and comparative examples of the present invention, and the cell temperature was 75 ° C. and the air utilization rate ( Under a condition of Uo) of 40%, air was supplied through a bubbler at 50 ° C. to perform a discharge test of a cell as a direct methanol fuel cell.

FIG. 3 shows the batteries A, B, and B of the embodiment of the present invention.
The life characteristics of C, D, E and the battery X of the comparative example as a hydrogen-air fuel cell were shown. FIG. 3 is a graph showing the relationship between the operation time of the battery and the voltage per cell (unit cell).

The average cell voltage at a current density of 300 mA / cm 2 was as follows: The initial voltages of batteries A, B, C, D, E and X were 806 mV, 789 mV and 800 m, respectively.
V, 768 mV, 762 mV and 721 mV. The characteristics after 3000 hours were 798 mV and 7 mV, respectively.
71 mV, 773 mV, 765 mV, 743 mV and 287 mV. Battery X of the comparative example was 434 mV
The batteries A, B, C, and
D and E are 8 mV, 18 mV, and 27 m, respectively.
V, 3 mV and 19 mV.

As described above, by using a surfactant satisfying the above molecular formula, the polymer electrolyte, carbon powder, and other binders are sufficiently dispersed, and the polymer electrolyte, carbon powder, and other binders are unevenly distributed. Without reducing the water content of the polymer electrolyte and the water repellency of the carbon powder are suppressed,
This is a result of maintaining the hydrogen ion conductivity, gas diffusing ability, and generated water discharging ability for a long time. In addition, it is possible to secure a sufficient effective reaction area of the catalyst, and also to secure a sufficient hydrogen ion conductivity in order to be able to form a hydrogen ion network by bonding between the polymer electrolyte ionomers, It was also effective in improving the initial characteristics.

Next, FIG. 4 shows the life characteristics of the batteries A, B, C, D and E of the example of the present invention and the battery X of the comparative example as a liquid fuel cell. FIG. 4 is a graph showing the relationship between the operating time of the battery and the voltage per cell (unit cell). However, the MEA for a liquid fuel cell uses Ketjen Black (Ketjen Black E, manufactured by Ketjen Black International Co., Ltd.)
C) 40% by weight of a Pt catalyst and 20% by weight of a Ru catalyst were supported on Ketjen Black (Ketjen Black EC manufactured by Ketjen Black International) from a catalyst body having 50% by weight of a Pt catalyst supported thereon. The test was performed by changing to a catalyst body.

The average cell voltage at a current density of 200 mA / cm 2 was 530 mV, 517 mV, and 497 mV, respectively, for the initial voltages of batteries A, B, C, D, E and X.
V, 522 mV, 479 mV and 410 mV. The characteristics after 3000 hours are 506 mV, 4
86 mV, 462 mV, 492 mV, 446 mV and 34 mV. The batteries A, B, C, and D of the examples were compared with the battery X of the comparative example which was deteriorated by 376 mV.
And E are 24 mV, 31 mV, 35 mV,
The drop was only 30 mV and 33 mV.

As described above, it was confirmed that the effect of adding the metal oxide to the electrode was similarly exhibited in the liquid fuel cell.

Tables 1 to 5 show the cell voltage characteristics of the cells A, B, C, D and E of the present invention as hydrogen-air fuel cells and liquid fuel cells after 1000 hours, respectively. Was. The current density is 2 for a hydrogen-air fuel cell.
50 mA / cm2, 150 mA for liquid fuel cell
/ Cm2.

[0066]

[Table 1]

[0067]

[Table 2]

[0068]

[Table 3]

[0069]

[Table 4]

[0070]

[Table 5]

In a hydrogen-air fuel cell, m and n
Are in the range of Examples 1 to 5, 75
Compared to the characteristics of 0 mV or more, each of the characteristics less than 650 mV was shown in the case of not being in the range of the example. When the values of m and n are within the range of the embodiment, the liquid fuel cell exhibited characteristics of 450 mV or more, respectively. Showed less than 30%.

Therefore, when the values of m and n of each surfactant are in the range of Examples 1 to 5, the polymer electrolyte, carbon powder, and other binders are sufficiently dispersed, and the The carbon powder and other binders are not unevenly distributed, and the decrease in the water content of the polymer electrolyte and the decrease in the water repellency of the carbon powder are suppressed. It is considered that the performance was maintained.

Although hydrogen and methanol were used as fuels in the present embodiment, similar results can be obtained by using fuel reformed hydrogen containing impurities such as carbon dioxide, nitrogen and carbon monoxide. Obtained. Similar results were obtained when liquid fuels such as ethanol, dimethyl ether, and ethylene glycol and mixtures thereof were used instead of methanol. The liquid fuel may be evaporated in advance and supplied as steam.

Further, the structure of this embodiment is not limited to the carbon powder and carbon paper shown in the embodiment, but may be applied to the case where other carbon black or carbon cloth such as Vulcan XC-72 or N330 is used. Was also effective.

[0075]

As described above, according to the present invention, in the fuel cell and the electrode, the humidity control performance of the electrode is optimized by the metal oxide. The polymer electrolyte fuel cell and the liquid exhibiting higher performance by controlling the water repellency of the catalyst layer and the gas diffusion layer, suppressing the deterioration over time, and maintaining high gas diffusion and drainage for a long period of time. Fuel cells as well as these electrodes can be provided.

The assembly (MEA) of the polymer electrolyte membrane and the electrode can be applied to a gas generator and a gas purifier for oxygen, ozone and hydrogen, and a gas sensor such as an oxygen sensor and an alcohol sensor. It is possible.

[Brief description of the drawings]

FIG. 1 shows ME as a component of a polymer electrolyte fuel cell.
Schematic sectional view showing the configuration of A

FIG. 2 is a schematic cross-sectional view showing a configuration of a unit cell which is a constituent element of a polymer electrolyte fuel cell.

FIG. 3 is a graph showing the voltage-operating time characteristics of the polymer electrolyte fuel cells of Examples and Comparative Examples of the present invention.

FIG. 4 is a graph showing voltage-operating time characteristics of the liquid fuel cells of Examples and Comparative Examples of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Polymer electrolyte membrane 12 Catalyst layer 13 Gas diffusion layer 14 Electrode 15 MEA 21 Separator plate 22 Gas flow path 23 Single cell

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akihiko Yoshida 1006 Kazuma Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Co., Ltd. F term (reference) 5H018 AA06 AA07 AS02 AS03 BB01 BB05 BB06 BB08 BB12 CC06 DD06 DD08 EE03 EE08 EE17 EE18 EE19 HH00 5H026 AA06 AA08 BB08 CC03 CX03 CX05 EE05 EE18 HH00

Claims (7)

[Claims] 1. A pair of electrodes comprising a hydrogen ion conductive polymer electrolyte membrane, a catalyst layer in contact with the hydrogen ion conductive polymer electrolyte membrane, and a gas diffusion layer in contact with the catalyst layer, and the electrode And a pair of conductive separators having a gas flow path for supplying and discharging a fuel gas to one of them and supplying and discharging an oxidizing gas to the other, wherein at least one of the catalyst layers comprises carbon powder and a surfactant. And a polymer electrolyte. 2. A pair of electrodes comprising a hydrogen ion conductive polymer electrolyte membrane, a catalyst layer in contact with the hydrogen ion conductive polymer electrolyte membrane, and a gas diffusion layer in contact with the catalyst layer. In a fuel cell comprising a pair of conductive separators having a gas flow path for supplying and discharging fuel gas to one of the electrodes and supplying and discharging an oxidizing gas to the other, at least one of the catalyst layers has a surface activity of carbon powder. A method for producing a fuel cell, comprising a mixture containing at least an agent and a polymer electrolyte. 3. The fuel cell according to claim 1, wherein the surfactant is represented by the following formula. Embedded image 4. The fuel cell according to claim 1, wherein the surfactant is represented by the following formula. Embedded image 5. The fuel cell according to claim 1, wherein the surfactant is represented by the following formula. Embedded image 6. The fuel cell according to claim 1, wherein the surfactant is represented by the following formula. Embedded image 7. The fuel cell according to claim 1, wherein the surfactant is represented by the following formula. Embedded image