JP2002015745A - Solid polymer fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solid polymer fuel cell that has an excellent output property and a high driving stability. SOLUTION: The solid polymer fuel cell is equipped with a cathode which contains a catalyst in which platinum or platinum alloy is carried in the carbon carrier having a specific surface area of 300-1,200 m2/g, and a perfluorocarbon polymer having sulfonic acid group. The metal content of the catalyst of the total mass of the catalyst is 52-80% and the catalyst content of the total quantity of the catalyst and the above polymer is 50-80 mass %.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a polymer electrolyte fuel cell having excellent output characteristics and high driving stability.

[0002]

2. Description of the Related Art A fuel cell is a cell that directly converts the reaction energy of a gas as a raw material into electric energy.
The oxygen fuel cell has a reaction product of only water in principle, and has almost no effect on the global environment. Among them, polymer electrolyte fuel cells, which use solid polymer electrolytes as electrolytes, can operate at room temperature and have high power density. High expectations are placed on power supplies and stationary power supplies.

In a polymer electrolyte fuel cell, a proton conductive ion exchange membrane is usually used as a polymer electrolyte, and in particular, a perfluorocarbon polymer having a sulfonic acid group (hereinafter referred to as a sulfonic acid type perfluorocarbon polymer). ) Is excellent in basic characteristics. In a polymer electrolyte fuel cell, an anode and a cathode composed of gas-diffusing electrode layers are arranged on both sides of an ion exchange membrane, and hydrogen as a fuel and oxygen or air as an oxidant are supplied to the anode and the cathode, respectively. To generate electricity.

The electrode layer of a polymer electrolyte fuel cell usually contains a supported catalyst in which platinum or a platinum alloy is supported on conductive carbon black or the like having a large specific surface area.
The reaction in the gas-diffusing electrode layer proceeds only at the three-phase interface where the electrolyte, catalyst and gas (hydrogen or oxygen) are simultaneously present. In particular, in the electrode layer, the performance can be improved by coating the catalyst with an ion exchange resin serving as an electrolyte and expanding the three-phase interface.

[0005]

At the cathode of a polymer electrolyte fuel cell, water is generated by a reduction reaction of oxygen serving as an oxidizing agent. Platinum is mainly used as the catalyst metal because it is stable and has high activity in the presence of an ion exchange resin composed of a sulfonic acid type perfluorocarbon polymer. However, compared to the oxidation reaction of hydrogen at the anode, the oxygen reduction reaction overpotential at the cathode is much larger, so in order to obtain excellent output characteristics, it is necessary to develop a cathode electrode catalyst with even higher oxygen reduction activity. It has been.

Accordingly, the present invention provides a polymer electrolyte fuel cell having excellent output characteristics and high driving stability, with a particular focus on an electrode catalyst for the cathode, in order to reduce the oxygen reduction reaction overvoltage at the cathode. With the goal.

[0007]

According to the present invention, there is provided a polymer electrolyte fuel cell comprising a solid polymer electrolyte membrane, and a cathode and an anode opposed to each other with the electrolyte membrane interposed therebetween, wherein the cathode has a sulfonic acid group. Having a perfluorocarbon polymer and platinum or a platinum alloy having a specific surface area of 300 to 120
A supported catalyst supported on a carbon carrier of 0 m ² / g; the supported catalyst comprises 50 to 80% by mass of the total amount of the perfluorocarbon polymer and the supported catalyst; Alternatively, the present invention provides a polymer electrolyte fuel cell, wherein a platinum alloy is contained in an amount of 52 to 80% in the total mass of the supported catalyst.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The content (support rate) of platinum or a platinum alloy (hereinafter referred to as catalyst metal) in a platinum-supported catalyst or a platinum alloy-supported catalyst used in a conventional fuel cell catalyst.
Is about 20 to 40% of the total mass of the supported catalyst. In the present invention, since the content of the catalyst metal in the supported catalyst at the cathode is as high as 52 to 80%, the catalyst metal particles are more concentrated on the reaction site (the three-phase interface between the catalyst, the resin, and the fuel gas). Can be present and high output is obtained.

From the viewpoint of expanding the reaction site, it is conceivable to use only metal particles such as platinum not supported on a carrier as a catalyst. However, in the present invention, a catalyst and a strongly acidic sulfonic acid-type perfluorocarbon polymer (hereinafter, referred to as an electrode resin) coexist in the electrode, and the catalyst is not supported on a carrier because the catalyst is coated with the electrode resin. In the case of a metal, the flow of electrons is obstructed, and the resistance of the electrode tends to increase, making it difficult to obtain high output. On the other hand, when the catalyst metal is supported on carbon, electron conductivity can be ensured by contact between carbons. When catalyst metal particles not supported on a carbon carrier are used, it is difficult to discharge water because a sufficient volume of pores having a pore diameter of 0.1 μm or more suitable for discharging water generated at the cathode cannot be obtained. .

In the present invention, an object is to obtain excellent output characteristics. If the catalyst metal loading is less than 52%, a reaction site sufficient to achieve the above object cannot be secured. On the other hand, when the content exceeds 80%, it becomes difficult to support the catalyst metal particles on the carbon carrier with good dispersibility, and the catalyst metal particles are used by being directly covered with a strongly acidic electrode resin and used. Causes the growth of platinum particles or platinum alloy particles. Further, similarly to the case where a catalyst metal not supported on a carbon carrier is used, a sufficient volume of pores having a pore diameter of 0.1 μm or more suitable for discharging water cannot be obtained. The loading ratio is more preferably 55 to 75%.
And more preferably 58 to 70%.

In order to ensure the stability of the catalytic metal particles in a state where the loading rate is high, the carbon carrier used in the present invention has a large specific surface area and is 300 to 1200 m ² / g. Specific surface area of carbon carrier is 300
When it is less than m ² / g, it becomes difficult to carry the catalyst metal particles mainly composed of platinum with good dispersibility. In addition, at the stage of preparing the catalyst, the particle diameter of the catalyst metal tends to increase, the surface area of the catalyst metal decreases, and it becomes difficult to obtain excellent output characteristics.

When the specific surface area is larger than 1200 m ² / g, the pore diameter is less than 0.1 μm, mainly 0.01 μm.
m, and the volume of the pores having a small pore diameter increases. In general, when a catalytic metal mainly composed of platinum is supported on a carbon carrier, a metal colloid having a particle diameter of about 1 to 10 nm is prepared by a wet method, and the metal is supported on the carbon carrier using the colloid. Therefore, when a carbon support having small pores developed as described above is used, the catalyst metal easily penetrates into the small pores and is supported. On the other hand, since the ion exchange resin hardly penetrates into the small pores, the three-phase interface serving as a reaction site cannot be expanded. In order to more stably support the catalyst metal particles with good dispersibility and effectively form a three-phase interface, the specific surface area of the carbon support is preferably 500 to 1000 m ² / g.

In the present invention, the supported catalyst is contained in the cathode in an amount of 50 to 80% by mass of the total amount of the electrode resin and the supported catalyst. When the content is less than 50% by mass, a sufficient reaction site of the cathode in the vicinity of the solid polymer electrolyte membrane (hereinafter simply referred to as an electrolyte membrane) cannot be secured, so that a high output cannot be obtained. Protons that pass from the anode through the electrolyte membrane and reach the cathode have a lower migration resistance in a region closer to the electrolyte membrane, and thus have an advantageous effect on the reaction at the cathode. Therefore, it is important to secure a sufficient reaction site of the cathode in the vicinity of the electrolyte membrane.

In particular, it is preferable to secure a sufficient reaction site in a region within 10 μm from the surface of the electrolyte membrane in the thickness direction of the cathode in the thickness direction of the cathode. That is, it is preferable that the cathode and the electrolyte membrane are in contact with each other, and in the region within 10 μm from the surface of the electrolyte membrane of the cathode in the thickness direction of the cathode, the supported catalyst is 50 to 80 times the total amount of the electrode resin and the supported catalyst. It is preferable that the content be contained by mass%. By doing so, it acts particularly advantageously on protons permeating the electrolyte membrane, reacts efficiently with oxygen supplied to the cathode and electrons from the current collector, and obtains high output characteristics.

On the other hand, when the ratio of the supported catalyst exceeds 80% by mass, the amount of the electrode resin covering the catalyst decreases relatively,
Protons are less likely to move. Further, the catalyst cannot be sufficiently coated with the electrode resin, and the number of reaction sites is reduced, so that high output characteristics cannot be obtained. More preferably, the proportion of the supported catalyst is 55 to 75% by mass, and the supply of gas to the electrolyte membrane,
It is more preferable that the content be 60 to 70% by mass from the viewpoint of the ease with which electrons flow from the current collector.

The electrode resin in the present invention preferably has an ion exchange capacity of 1.0 to 1.5 meq / g dry resin, particularly preferably 1.1 to 1.4 meq / g dry resin. If the amount is less than 1.0 meq / g dry resin, the electrode resin has a low water content, so that the resistance of the electrode increases and it is difficult to increase the output of the battery. If the amount exceeds 1.5 meq / g dry resin, the electrode resin is easily dissolved in water, and the electrode resin is eluted during the operation of the fuel cell, and the output voltage may decrease.

As the carbon carrier in the present invention, X
The average lattice spacing d _{002 of the} [002] plane measured by line diffraction is preferably from 0.340 to 0.362 nm. d ₀₀₂ is a physical property that is a measure of the degree of graphitization of carbon. Carbon having a high degree of graphitization has a reduced surface functional group concentration and high water repellency, and easily discharges reaction-produced water generated at the cathode. for that reason,
Flooding in the electrode pores is suppressed, and a stable output can be obtained over a long period.

If d ₀₀₂ is less than 0.340 nm, the degree of graphitization of the carbon carrier is too high and the specific surface area is reduced, so that the dispersibility of the supported catalyst metal is reduced or the surface area of the catalyst metal is reduced. Thus, the electrode activity may be reduced. On the other hand, if it exceeds 0.362 nm, the degree of graphitization is too low to improve the electrode activity, and sufficient water repellency and corrosion resistance to an electrode resin which is a strong acid may not be obtained.

For ordinary carbon black or activated carbon having a specific surface area of 300 m ² / g or more, d ₀₀₂ is 0.355.
Approximately 0.385 nm, and the graphitization has not progressed much. Therefore, the carbon carrier in the present invention is carbon black or activated carbon of 1000 to 220
It is preferable to obtain by heating at 0 ° C., particularly 1200 to 1800 ° C. to progress the graphitization. If the temperature of the heat treatment is less than 1000 ° C., the graphitization does not proceed sufficiently, so that the water repellency and corrosion resistance do not increase so much. On the other hand, when the temperature of the heat treatment exceeds 2200 ° C., the graphitization proceeds remarkably, and the specific surface area is greatly reduced. Therefore, it becomes difficult to carry the catalyst metal particles with good dispersibility.

As the carbon carrier in the present invention, any of the known carbon materials can be used. Among them, channel black, furnace black, thermal black,
Carbon black such as acetylene black and activated carbon are preferred.

The catalyst metal in the present invention is preferably a platinum-based catalyst which is highly active in the oxygen reduction reaction at the cathode. Further, for the purpose of imparting high activity and stability as an electrode catalyst, a platinum alloy can be used, and in this case, a platinum group metal other than platinum, gold, cobalt, chromium, nickel, iron , Molybdenum, tungsten, aluminum, silicon, rhenium,
An alloy of platinum and one or more metals selected from the group consisting of zinc and tin can be used. The platinum alloy may be an intermetallic compound of platinum and the above metal, for example, a binary intermetallic compound.

When a platinum alloy is used, its composition depends on the type of metal to be alloyed with platinum.
It is preferable that the content be 0 atomic%. The alloying method may be performed under an inert gas atmosphere.
It is preferable to heat-treat at a temperature of 00 to 900 ° C. to form an alloy.

As a method for producing the supported catalyst in the present invention, for example, a carbon powder is dispersed in an aqueous solution of chloroplatinic acid (which may contain a solvent such as alcohol) as a salt of platinum. When a platinum alloy is used as the catalyst metal, a compound containing a metal to be alloyed with platinum is dissolved or dispersed in the liquid. Next, heat and stir,
A compound containing platinum or a compound containing platinum and the above metal is adsorbed on carbon powder. PH in solution, if necessary
May be adjusted to the alkali side, and the compound adsorbed on the carbon powder may be a hydroxide. Further, after appropriately performing filtration, washing, and drying, a reduction treatment is performed with hydrogen gas or the like, and then a heat treatment is performed in an atmosphere of an inert gas such as helium, argon, or nitrogen to obtain a supported catalyst.

The particle diameter of platinum or a platinum alloy (including an intermetallic compound) constituting the supported catalyst in the present invention is preferably 1 to 20 nm in order to obtain high activity, and particularly preferably 1.2 to 5 nm. Is preferred. Particle size is 1.2
When it is less than nm, the catalytic metal particles are likely to aggregate, and are easily dissolved in the electrode resin, and then stably re-precipitated again. As a result, the particle diameter tends to increase. On the other hand, if the thickness exceeds 5 nm, the surface area of the catalyst metal becomes relatively small, so that sufficient activity cannot be obtained.

In the present invention, the resin constituting the electrolyte membrane is preferably a sulfonic acid type perfluorocarbon polymer as in the case of the cathode electrode resin. Further, it is preferable that the anode contains a resin similarly to the cathode, and a sulfonic acid type perfluorocarbon polymer is preferable. The resin contained in the cathode, the resin contained in the anode, and the resin constituting the electrolyte membrane may be the same or different, but all of them are, particularly, polymerized units based on CF ₂ = CF ₂ and CF ₂ = CF _{- (OCF 2 CFX) m -O} p - (CF 2) n -
SO ₃ H-based polymerization unit (wherein, X is a fluorine atom or a trifluoromethyl group, m is an integer of 0 to 3, n is an integer of 1 to 12, and p is 0 or 1. Is preferred.

In the polymer electrolyte fuel cell of the present invention,
The electrodes (cathode and anode) and the electrolyte membrane are preferably joined. When manufacturing an electrode / membrane assembly,
A method of forming electrodes directly on an ion exchange membrane serving as an electrolyte membrane, a method of forming an electrode once on a base material such as carbon paper or carbon cloth, and then bonding this to an ion exchange membrane, or on another flat plate. Various methods can be adopted, such as a method of forming an electrode on the substrate and transferring the electrode to an ion exchange membrane.

Specifically, a liquid in which a supported catalyst and an electrode resin are dissolved or dispersed in a medium is prepared, and a water repellent, a pore former, a thickener, a diluting solvent and the like are mixed with the liquid as required. Then, the coating liquid is applied to a base material such as an ion exchange membrane or carbon paper by spraying, coating, or filtering to form an electrode. When the electrode is not formed on the ion exchange membrane, a hot press method,
A bonding method (see Japanese Patent Application Laid-Open No. 7-220743) and the like can be applied.

[0028]

EXAMPLES Hereinafter, specific embodiments of the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

[Example 1 (Example)] Specific surface area of 5 g: 800
m ² / g, the average lattice spacing (hereinafter simply referred to as d ₀₀₂ ) of the [002] plane obtained by X-ray diffraction is 0.370.
nm carbon black was dispersed in ion-exchanged water, 27 g of chloroplatinic acid aqueous solution and 50 g of 35% formalin were added thereto, and the mixture was cooled to -10 ° C and stirred. This is 2
After 0 g of a 40% aqueous sodium hydroxide solution was added dropwise and refluxed for 1 hour, the mixture was filtered and washed, and platinum was loaded on a carbon carrier at 60% of the total weight of the loaded catalyst (hereinafter, the ratio of platinum to the total weight of the loaded catalyst was loaded). %). A platinum-supported catalyst was obtained. According to powder X-ray diffraction of the obtained platinum-supported catalyst, the platinum particle diameter was about 2.3 nm.

3.5 g of the above-mentioned platinum-supported catalyst, polymerized units based on CF ₂ = CF ₂ as the electrode resin, and CF ₂ = CF-O
Mixing ethanol / water with 1.5 g of a copolymer (ion exchange capacity: 1.1 meq / g dry resin) composed of polymerized units based on CF ₂ CF (CF ₃ ) O (CF ₂ ) ₂ —SO ₃ H This was mixed with a solvent to obtain a catalyst ink. This catalyst ink was applied on a carbon cloth so that the platinum amount was 0.5 mg / cm ² , to obtain a gas diffusion electrode. Thickness 50μm
An ion-exchange membrane (trade name: Flemion, manufactured by Asahi Glass Co., Ltd.) comprising a sulfonic acid-type perfluorocarbon polymer as an electrolyte membrane, the above-mentioned gas diffusion electrode as a cathode,
A gas-diffusion electrode (trade name: ELAT) manufactured by E-TEK was used as the anode, and an electrolyte membrane was sandwiched between the cathode and the anode and hot-pressed to produce a membrane-electrode assembly.

The obtained membrane / electrode assembly was assembled in a measuring cell, and hydrogen was used as a fuel gas, air was used as an oxidizing gas, and the cell temperature was 0.15 MPa (absolute pressure).
After measuring the initial voltage at a constant current density drive of 1 A / cm ^{2 at} ° C., a continuous operation test was performed at a constant current density drive of 1 A / cm ² , and the cell voltage after 200 hours and 1000 hours was measured. . Table 1 shows the specific surface area of the (carbon) carrier, the platinum loading, the content of the catalyst (mass ratio of the catalyst to the total amount of the catalyst and the electrode resin), and the results of the above measurements.

When the cross section of the membrane-electrode assembly was observed with a scanning electron microscope (SEM), the cathode was closely bonded to the membrane, and the thickness of the cathode was 10 μm.
Met. Furthermore, an energy dispersive X-ray fluorescence analyzer (E
DAX), it was confirmed that the supported catalyst at the cathode had a platinum loading of 60%. Further, from the results of sulfur analysis by EDAX and the results of platinum analysis, it was confirmed that the content of the supported catalyst was 70% by mass of the total amount of the electrode resin and the supported catalyst.

[Example 2 (Example)] Specific surface area 1500 m ²
/ G of carbon black in an argon gas atmosphere for 20
A heat treatment was performed at 00 ° C. for 3 hours to perform a graphitization treatment.
The specific surface area of this carbon black by the nitrogen adsorption method is
650 m ² / g, d ₀₀₂ was 0.347 nm. A platinum-supported catalyst was obtained in the same manner as in Example 1 except that this carbon black was used as a carbon carrier. According to powder X-ray diffraction of the platinum-supported catalyst, the platinum particle size was about 1.8 nm. A cathode was prepared in the same manner as in Example 1 except that this supported catalyst was used, and a membrane / electrode assembly was prepared in the same manner as in Example 1 and evaluated as in Example 1. Table 1 shows the results.

Example 3 (Example) As a carbon carrier,
A platinum-supported catalyst was prepared in the same manner as in Example 1 except that carbon black having a specific surface area of 400 m ² / g and d ₀₀₂ of 0.358 nm was used, and the loading ratio of platinum was 55%. A cathode was prepared in the same manner as in Example 1 except that the same sulfonic acid type perfluorocarbon polymer as in Example 1 was used, and the mixing ratio was changed so that the mass ratio of the catalyst and the polymer was 60:40. A membrane / electrode assembly was prepared in the same manner as in Example 1 and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 4 (Example) The loading ratio of platinum was 75%.
A platinum-supported catalyst was prepared in the same manner as in Example 1 except that
The same procedure as in Example 1 was carried out except that the platinum-supported catalyst and the same sulfonic acid type perfluorocarbon polymer as in Example 1 were used, and the mixing ratio was changed so that the mass ratio between the catalyst and the polymer became 75:25. A cathode was prepared, and a membrane was prepared in the same manner as in Example 1.
An electrode assembly was prepared and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 5 (Example) Using the same platinum-supported catalyst and sulfonic acid type perfluorocarbon polymer as in Example 1,
A cathode was produced in the same manner as in Example 1 except that the mixing ratio was changed so that the mass ratio of the catalyst and the polymer became 75:25, and a membrane / electrode assembly was produced in the same manner as in Example 1. Example 1
Was evaluated in the same way as Table 1 shows the results.

Example 6 (Comparative Example) Using the same platinum-supported catalyst and sulfonic acid type perfluorocarbon polymer as in Example 1,
A cathode was prepared in the same manner as in Example 1 except that the mixing ratio was changed so that the mass ratio of the catalyst to the polymer was 35:65, and a membrane / electrode assembly was prepared in the same manner as in Example 1. Example 1
Was evaluated in the same way as Table 1 shows the results.

Example 7 (Comparative Example) Using the same platinum-supported catalyst and sulfonic acid type perfluorocarbon polymer as in Example 1,
A cathode was prepared in the same manner as in Example 1 except that the mixing ratio was changed so that the mass ratio of the catalyst to the polymer was 85:15, and a membrane / electrode assembly was prepared in the same manner as in Example 1. Example 1
Was evaluated in the same way as Table 1 shows the results.

Example 8 (Comparative Example) The loading ratio of platinum was 30%.
A platinum-supported catalyst was obtained in the same manner as in Example 1, except that the catalyst was changed to. According to powder X-ray diffraction of the platinum-supported catalyst, the platinum particle diameter was about 2.1 nm. A cathode was prepared in the same manner as in Example 1 except that this supported catalyst was used, and a membrane / electrode assembly was prepared in the same manner as in Example 1 and evaluated as in Example 1. Table 1 shows the results.

Further, the cross section of the above-mentioned membrane / electrode assembly was SEM
As a result, the thickness of the cathode was 25 μm. Further, elemental analysis was carried out by EDAX, and it was confirmed that the supported platinum ratio of the supported catalyst of the cathode was 30%. Further, from the results of sulfur analysis by EDAX and the results of platinum analysis, it was confirmed that the content of the supported catalyst was 70% by mass of the total amount of the electrode resin and the supported catalyst.

Example 9 (Comparative Example) As a carbon carrier,
A platinum-supported catalyst was obtained in the same manner as in Example 1, except that carbon black having a specific surface area of 250 m ² / g and a d ₀₀₂ of 0.357 nm was used. According to powder X-ray diffraction of the platinum-supported catalyst, the platinum particle size was about 5.5 nm. A cathode was prepared in the same manner as in Example 1 except that this supported catalyst was used, and a membrane / electrode assembly was prepared in the same manner as in Example 1 and evaluated as in Example 1. Table 1 shows the results.

Example 10 (Comparative Example) A cathode was prepared in the same manner as in Example 1 except that platinum fine particles having a particle diameter of 4 nm (manufactured by NE Chemcat) were used instead of the platinum-supported catalyst. Similarly, a membrane / electrode assembly was prepared and evaluated in the same manner as in Example 1. Table 1 shows the results.

Example 11 (Comparative Example) The loading rate of platinum was 50
%, A platinum-supported catalyst was prepared in the same manner as in Example 3, a cathode was prepared in the same manner as in Example 3, a membrane / electrode assembly was prepared in the same manner as in Example 1, and the evaluation was performed in the same manner as in Example 1. . Table 1 shows the results.

Example 12 (Comparative Example) The loading rate of platinum was 82
%, A cathode was prepared in the same manner as in Example 5, a membrane / electrode assembly was prepared in the same manner as in Example 1, and the evaluation was performed in the same manner as in Example 1. Table 1 shows the results.

[0045]

[Table 1]

[0046]

According to the present invention, a solid polymer type fuel having a cathode is provided by including a high mass ratio of a catalyst having a high proportion of a catalytic metal component in the total mass of a supported catalyst in the cathode. The battery has high output characteristics and driving stability.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Toshihiro Tanuma 1150 Hazawa-cho, Kanagawa-ku, Yokohama-shi, Kanagawa Prefecture F-term in Asahi Glass Co., Ltd. HH02 HH03 HH05

Claims (4)

[Claims] 1. A solid polymer electrolyte fuel cell comprising a solid polymer electrolyte membrane and a cathode and an anode opposed to each other with the electrolyte membrane interposed therebetween, wherein the cathode comprises a perfluorocarbon polymer having a sulfonic acid group; Or a supported catalyst in which a platinum alloy is supported on a carbon support having a specific surface area of 300 to 1200 m ² / g, wherein the supported catalyst has a total amount of 50% of the perfluorocarbon polymer and the supported catalyst.
Wherein the supported catalyst contains 52 to 80% of platinum or a platinum alloy in the total mass of the supported catalyst. 2. The polymer electrolyte fuel cell according to claim 1, wherein the perfluorocarbon polymer is an ion exchange capacity of 1.0 to 1.5 meq / g dry resin. 3. An average lattice spacing d _{002 of the} [002] plane measured by X-ray diffraction is 0.34.
The polymer electrolyte fuel cell according to claim 1, wherein the thickness is from 0 to 0.362 nm. 4. The supported catalyst is present in an amount of 50 to 80% by mass of the total amount of the perfluorocarbon polymer and the supported catalyst in a region from the surface of the electrolyte membrane to a thickness of the cathode within 10 μm. The polymer electrolyte fuel cell according to claim 1, 2 or 3.